[chore]: Bump github.com/KimMachineGun/automemlimit from 0.2.4 to 0.2.5 (#1666)
Bumps [github.com/KimMachineGun/automemlimit](https://github.com/KimMachineGun/automemlimit) from 0.2.4 to 0.2.5. - [Release notes](https://github.com/KimMachineGun/automemlimit/releases) - [Commits](https://github.com/KimMachineGun/automemlimit/compare/v0.2.4...v0.2.5) --- updated-dependencies: - dependency-name: github.com/KimMachineGun/automemlimit dependency-type: direct:production update-type: version-update:semver-patch ... Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
This commit is contained in:
parent
3f9b2336c0
commit
57dc742c76
7
go.mod
7
go.mod
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@ -15,7 +15,7 @@ require (
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codeberg.org/gruf/go-runners v1.6.1
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codeberg.org/gruf/go-sched v1.2.3
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codeberg.org/gruf/go-store/v2 v2.2.2
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github.com/KimMachineGun/automemlimit v0.2.4
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github.com/KimMachineGun/automemlimit v0.2.5
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github.com/abema/go-mp4 v0.10.1
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github.com/buckket/go-blurhash v1.1.0
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github.com/coreos/go-oidc/v3 v3.5.0
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@ -79,8 +79,8 @@ require (
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github.com/aymerick/douceur v0.2.0 // indirect
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github.com/bytedance/sonic v1.8.0 // indirect
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github.com/chenzhuoyu/base64x v0.0.0-20221115062448-fe3a3abad311 // indirect
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github.com/cilium/ebpf v0.4.0 // indirect
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github.com/containerd/cgroups v1.0.4 // indirect
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github.com/cilium/ebpf v0.9.1 // indirect
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github.com/containerd/cgroups/v3 v3.0.1 // indirect
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github.com/coreos/go-systemd/v22 v22.3.2 // indirect
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github.com/davecgh/go-spew v1.1.1 // indirect
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github.com/docker/go-units v0.4.0 // indirect
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@ -100,7 +100,6 @@ require (
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github.com/go-xmlfmt/xmlfmt v0.0.0-20211206191508-7fd73a941850 // indirect
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github.com/goccy/go-json v0.10.0 // indirect
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github.com/godbus/dbus/v5 v5.0.4 // indirect
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github.com/gogo/protobuf v1.3.2 // indirect
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github.com/golang-jwt/jwt v3.2.2+incompatible // indirect
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github.com/golang/geo v0.0.0-20210211234256-740aa86cb551 // indirect
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github.com/golang/protobuf v1.5.2 // indirect
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19
go.sum
19
go.sum
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@ -88,8 +88,8 @@ codeberg.org/gruf/go-store/v2 v2.2.2/go.mod h1:QRM3LUAfYyoGMWLTqA1WzohxQgYqPFiVv
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dmitri.shuralyov.com/gpu/mtl v0.0.0-20190408044501-666a987793e9/go.mod h1:H6x//7gZCb22OMCxBHrMx7a5I7Hp++hsVxbQ4BYO7hU=
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github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
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github.com/BurntSushi/xgb v0.0.0-20160522181843-27f122750802/go.mod h1:IVnqGOEym/WlBOVXweHU+Q+/VP0lqqI8lqeDx9IjBqo=
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github.com/KimMachineGun/automemlimit v0.2.4 h1:GBty8TK8k0aJer1Pq5/3Vdt2ef+YpLhcqNo+PSD5CoI=
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github.com/KimMachineGun/automemlimit v0.2.4/go.mod h1:38QAnnnNhnFuAIW3+aPlaVUHqzE9buJYZK3m/jsra8E=
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github.com/KimMachineGun/automemlimit v0.2.5 h1:+wWu5hu/dVqWWauY2rZmlGN+z7SnP02gMVQpcP7xvrk=
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github.com/KimMachineGun/automemlimit v0.2.5/go.mod h1:pJhTW/nWJMj6SnWSU2TEKSlCaM+1N5Mej+IfS/5/Ol0=
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github.com/Masterminds/semver/v3 v3.1.1 h1:hLg3sBzpNErnxhQtUy/mmLR2I9foDujNK030IGemrRc=
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github.com/Masterminds/semver/v3 v3.1.1/go.mod h1:VPu/7SZ7ePZ3QOrcuXROw5FAcLl4a0cBrbBpGY/8hQs=
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github.com/abema/go-mp4 v0.10.1 h1:wOhZgNxjduc8r4FJdwPa5x/gdBSSX+8MTnfNj/xkJaE=
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@ -113,8 +113,8 @@ github.com/chenzhuoyu/base64x v0.0.0-20221115062448-fe3a3abad311/go.mod h1:b583j
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github.com/chzyer/logex v1.1.10/go.mod h1:+Ywpsq7O8HXn0nuIou7OrIPyXbp3wmkHB+jjWRnGsAI=
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github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e/go.mod h1:nSuG5e5PlCu98SY8svDHJxuZscDgtXS6KTTbou5AhLI=
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github.com/chzyer/test v0.0.0-20180213035817-a1ea475d72b1/go.mod h1:Q3SI9o4m/ZMnBNeIyt5eFwwo7qiLfzFZmjNmxjkiQlU=
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github.com/cilium/ebpf v0.4.0 h1:QlHdikaxALkqWasW8hAC1mfR0jdmvbfaBdBPFmRSglA=
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github.com/cilium/ebpf v0.4.0/go.mod h1:4tRaxcgiL706VnOzHOdBlY8IEAIdxINsQBcU4xJJXRs=
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github.com/cilium/ebpf v0.9.1 h1:64sn2K3UKw8NbP/blsixRpF3nXuyhz/VjRlRzvlBRu4=
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github.com/cilium/ebpf v0.9.1/go.mod h1:+OhNOIXx/Fnu1IE8bJz2dzOA+VSfyTfdNUVdlQnxUFY=
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github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
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github.com/cncf/udpa/go v0.0.0-20191209042840-269d4d468f6f/go.mod h1:M8M6+tZqaGXZJjfX53e64911xZQV5JYwmTeXPW+k8Sc=
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github.com/cncf/udpa/go v0.0.0-20200629203442-efcf912fb354/go.mod h1:WmhPx2Nbnhtbo57+VJT5O0JRkEi1Wbu0z5j0R8u5Hbk=
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@ -122,8 +122,8 @@ github.com/cncf/udpa/go v0.0.0-20201120205902-5459f2c99403/go.mod h1:WmhPx2Nbnht
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github.com/cnf/structhash v0.0.0-20201127153200-e1b16c1ebc08 h1:ox2F0PSMlrAAiAdknSRMDrAr8mfxPCfSZolH+/qQnyQ=
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github.com/cockroachdb/apd v1.1.0 h1:3LFP3629v+1aKXU5Q37mxmRxX/pIu1nijXydLShEq5I=
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github.com/cockroachdb/apd v1.1.0/go.mod h1:8Sl8LxpKi29FqWXR16WEFZRNSz3SoPzUzeMeY4+DwBQ=
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github.com/containerd/cgroups v1.0.4 h1:jN/mbWBEaz+T1pi5OFtnkQ+8qnmEbAr1Oo1FRm5B0dA=
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github.com/containerd/cgroups v1.0.4/go.mod h1:nLNQtsF7Sl2HxNebu77i1R0oDlhiTG+kO4JTrUzo6IA=
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github.com/containerd/cgroups/v3 v3.0.1 h1:4hfGvu8rfGIwVIDd+nLzn/B9ZXx4BcCjzt5ToenJRaE=
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github.com/containerd/cgroups/v3 v3.0.1/go.mod h1:/vtwk1VXrtoa5AaZLkypuOJgA/6DyPMZHJPGQNtlHnw=
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github.com/coreos/go-oidc/v3 v3.5.0 h1:VxKtbccHZxs8juq7RdJntSqtXFtde9YpNpGn0yqgEHw=
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github.com/coreos/go-oidc/v3 v3.5.0/go.mod h1:ecXRtV4romGPeO6ieExAsUK9cb/3fp9hXNz1tlv8PIM=
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github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
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@ -172,7 +172,6 @@ github.com/envoyproxy/protoc-gen-validate v0.1.0/go.mod h1:iSmxcyjqTsJpI2R4NaDN7
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github.com/fasthttp-contrib/websocket v0.0.0-20160511215533-1f3b11f56072/go.mod h1:duJ4Jxv5lDcvg4QuQr0oowTf7dz4/CR8NtyCooz9HL8=
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github.com/fatih/structs v1.1.0 h1:Q7juDM0QtcnhCpeyLGQKyg4TOIghuNXrkL32pHAUMxo=
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github.com/fatih/structs v1.1.0/go.mod h1:9NiDSp5zOcgEDl+j00MP/WkGVPOlPRLejGD8Ga6PJ7M=
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github.com/frankban/quicktest v1.11.3/go.mod h1:wRf/ReqHper53s+kmmSZizM8NamnL3IM0I9ntUbOk+k=
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github.com/frankban/quicktest v1.14.3 h1:FJKSZTDHjyhriyC81FLQ0LY93eSai0ZyR/ZIkd3ZUKE=
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github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
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github.com/fsnotify/fsnotify v1.4.9/go.mod h1:znqG4EE+3YCdAaPaxE2ZRY/06pZUdp0tY4IgpuI1SZQ=
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@ -231,8 +230,6 @@ github.com/godbus/dbus/v5 v5.0.4 h1:9349emZab16e7zQvpmsbtjc18ykshndd8y2PG3sgJbA=
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github.com/godbus/dbus/v5 v5.0.4/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
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github.com/gofrs/uuid v4.0.0+incompatible h1:1SD/1F5pU8p29ybwgQSwpQk+mwdRrXCYuPhW6m+TnJw=
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github.com/gofrs/uuid v4.0.0+incompatible/go.mod h1:b2aQJv3Z4Fp6yNu3cdSllBxTCLRxnplIgP/c0N/04lM=
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github.com/gogo/protobuf v1.3.2 h1:Ov1cvc58UF3b5XjBnZv7+opcTcQFZebYjWzi34vdm4Q=
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github.com/gogo/protobuf v1.3.2/go.mod h1:P1XiOD3dCwIKUDQYPy72D8LYyHL2YPYrpS2s69NZV8Q=
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github.com/golang-jwt/jwt v3.2.1+incompatible/go.mod h1:8pz2t5EyA70fFQQSrl6XZXzqecmYZeUEB8OUGHkxJ+I=
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github.com/golang-jwt/jwt v3.2.2+incompatible h1:IfV12K8xAKAnZqdXVzCZ+TOjboZ2keLg81eXfW3O+oY=
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github.com/golang-jwt/jwt v3.2.2+incompatible/go.mod h1:8pz2t5EyA70fFQQSrl6XZXzqecmYZeUEB8OUGHkxJ+I=
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@ -396,7 +393,6 @@ github.com/jtolds/gls v4.20.0+incompatible/go.mod h1:QJZ7F/aHp+rZTRtaJ1ow/lLfFfV
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github.com/k0kubun/colorstring v0.0.0-20150214042306-9440f1994b88/go.mod h1:3w7q1U84EfirKl04SVQ/s7nPm1ZPhiXd34z40TNz36k=
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github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51 h1:Z9n2FFNUXsshfwJMBgNA0RU6/i7WVaAegv3PtuIHPMs=
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github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51/go.mod h1:CzGEWj7cYgsdH8dAjBGEr58BoE7ScuLd+fwFZ44+/x8=
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github.com/kisielk/errcheck v1.5.0/go.mod h1:pFxgyoBC7bSaBwPgfKdkLd5X25qrDl4LWUI2bnpBCr8=
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github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
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github.com/klauspost/compress v1.10.4/go.mod h1:aoV0uJVorq1K+umq18yTdKaF57EivdYsUV+/s2qKfXs=
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github.com/klauspost/compress v1.10.10/go.mod h1:aoV0uJVorq1K+umq18yTdKaF57EivdYsUV+/s2qKfXs=
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@ -823,7 +819,6 @@ golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7w
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golang.org/x/sys v0.0.0-20201201145000-ef89a241ccb3/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
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golang.org/x/sys v0.0.0-20210104204734-6f8348627aad/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
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golang.org/x/sys v0.0.0-20210119212857-b64e53b001e4/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
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golang.org/x/sys v0.0.0-20210124154548-22da62e12c0c/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
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golang.org/x/sys v0.0.0-20210225134936-a50acf3fe073/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
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golang.org/x/sys v0.0.0-20210423185535-09eb48e85fd7/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
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golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
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@ -904,7 +899,6 @@ golang.org/x/tools v0.0.0-20200501065659-ab2804fb9c9d/go.mod h1:EkVYQZoAsY45+roY
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golang.org/x/tools v0.0.0-20200512131952-2bc93b1c0c88/go.mod h1:EkVYQZoAsY45+roYkvgYkIh4xh/qjgUK9TdY2XT94GE=
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golang.org/x/tools v0.0.0-20200515010526-7d3b6ebf133d/go.mod h1:EkVYQZoAsY45+roYkvgYkIh4xh/qjgUK9TdY2XT94GE=
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golang.org/x/tools v0.0.0-20200618134242-20370b0cb4b2/go.mod h1:EkVYQZoAsY45+roYkvgYkIh4xh/qjgUK9TdY2XT94GE=
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golang.org/x/tools v0.0.0-20200619180055-7c47624df98f/go.mod h1:EkVYQZoAsY45+roYkvgYkIh4xh/qjgUK9TdY2XT94GE=
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golang.org/x/tools v0.0.0-20200729194436-6467de6f59a7/go.mod h1:njjCfa9FT2d7l9Bc6FUM5FLjQPp3cFF28FI3qnDFljA=
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golang.org/x/tools v0.0.0-20200804011535-6c149bb5ef0d/go.mod h1:njjCfa9FT2d7l9Bc6FUM5FLjQPp3cFF28FI3qnDFljA=
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golang.org/x/tools v0.0.0-20200825202427-b303f430e36d/go.mod h1:njjCfa9FT2d7l9Bc6FUM5FLjQPp3cFF28FI3qnDFljA=
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@ -913,7 +907,6 @@ golang.org/x/tools v0.0.0-20201110124207-079ba7bd75cd/go.mod h1:emZCQorbCU4vsT4f
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golang.org/x/tools v0.0.0-20201201161351-ac6f37ff4c2a/go.mod h1:emZCQorbCU4vsT4fOWvOPXz4eW1wZW4PmDk9uLelYpA=
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golang.org/x/tools v0.0.0-20201208233053-a543418bbed2/go.mod h1:emZCQorbCU4vsT4fOWvOPXz4eW1wZW4PmDk9uLelYpA=
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golang.org/x/tools v0.0.0-20210105154028-b0ab187a4818/go.mod h1:emZCQorbCU4vsT4fOWvOPXz4eW1wZW4PmDk9uLelYpA=
|
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golang.org/x/tools v0.0.0-20210106214847-113979e3529a/go.mod h1:emZCQorbCU4vsT4fOWvOPXz4eW1wZW4PmDk9uLelYpA=
|
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golang.org/x/tools v0.0.0-20210108195828-e2f9c7f1fc8e/go.mod h1:emZCQorbCU4vsT4fOWvOPXz4eW1wZW4PmDk9uLelYpA=
|
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golang.org/x/tools v0.1.0/go.mod h1:xkSsbof2nBLbhDlRMhhhyNLN/zl3eTqcnHD5viDpcZ0=
|
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golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
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@ -4,8 +4,9 @@
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package memlimit
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import (
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"github.com/containerd/cgroups"
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v2 "github.com/containerd/cgroups/v2"
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"github.com/containerd/cgroups/v3"
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"github.com/containerd/cgroups/v3/cgroup1"
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"github.com/containerd/cgroups/v3/cgroup2"
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)
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const (
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@ -25,12 +26,14 @@ func FromCgroup() (uint64, error) {
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// FromCgroupV1 returns the memory limit from the cgroup v1.
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func FromCgroupV1() (uint64, error) {
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cg, err := cgroups.Load(cgroups.SingleSubsystem(cgroups.V1, cgroups.Memory), cgroups.RootPath)
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cg, err := cgroup1.Load(cgroup1.RootPath, cgroup1.WithHiearchy(
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cgroup1.SingleSubsystem(cgroup1.Default, cgroup1.Memory),
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))
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if err != nil {
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return 0, err
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}
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metrics, err := cg.Stat(cgroups.IgnoreNotExist)
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metrics, err := cg.Stat(cgroup1.IgnoreNotExist)
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if err != nil {
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return 0, err
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} else if metrics.Memory == nil {
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@ -42,12 +45,12 @@ func FromCgroupV1() (uint64, error) {
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// FromCgroupV2 returns the memory limit from the cgroup v2.
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func FromCgroupV2() (uint64, error) {
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path, err := v2.NestedGroupPath("")
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path, err := cgroup2.NestedGroupPath("")
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if err != nil {
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return 0, err
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}
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m, err := v2.LoadManager(cgroupMountPoint, path)
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m, err := cgroup2.Load(path, cgroup2.WithMountpoint(cgroupMountPoint))
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if err != nil {
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return 0, err
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}
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|
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@ -36,6 +36,15 @@ var (
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// If AUTOMEMLIMIT is not set, it defaults to 0.9. (10% is the headroom for memory sources the Go runtime is unaware of.)
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// If GOMEMLIMIT is already set or AUTOMEMLIMIT=off, this function does nothing.
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func SetGoMemLimitWithEnv() {
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snapshot := debug.SetMemoryLimit(-1)
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defer func() {
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err := recover()
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if err != nil {
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logger.Printf("panic during SetGoMemLimitWithEnv, rolling back to previous value %d: %v\n", snapshot, err)
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debug.SetMemoryLimit(snapshot)
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}
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}()
|
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if os.Getenv(envAUTOMEMLIMIT_DEBUG) == "true" {
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logger = log.Default()
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}
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@ -97,6 +106,7 @@ func cappedFloat2Int(f float64) int64 {
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}
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return int64(f)
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}
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// Limit is a helper Provider function that returns the given limit.
|
||||
func Limit(limit uint64) func() (uint64, error) {
|
||||
return func() (uint64, error) {
|
||||
|
|
|
@ -5,6 +5,7 @@
|
|||
*.so
|
||||
*.dylib
|
||||
*.o
|
||||
!*_bpf*.o
|
||||
|
||||
# Test binary, build with `go test -c`
|
||||
*.test
|
||||
|
|
|
@ -0,0 +1,28 @@
|
|||
---
|
||||
issues:
|
||||
exclude-rules:
|
||||
# syscall param structs will have unused fields in Go code.
|
||||
- path: syscall.*.go
|
||||
linters:
|
||||
- structcheck
|
||||
|
||||
linters:
|
||||
disable-all: true
|
||||
enable:
|
||||
- deadcode
|
||||
- errcheck
|
||||
- goimports
|
||||
- gosimple
|
||||
- govet
|
||||
- ineffassign
|
||||
- misspell
|
||||
- staticcheck
|
||||
- structcheck
|
||||
- typecheck
|
||||
- unused
|
||||
- varcheck
|
||||
|
||||
# Could be enabled later:
|
||||
# - gocyclo
|
||||
# - maligned
|
||||
# - gosec
|
|
@ -57,7 +57,7 @@ Objects
|
|||
loading a spec will fail because the kernel is too old, or a feature is not
|
||||
enabled. There are multiple ways the library deals with that:
|
||||
|
||||
* Fallback: older kernels don't allowing naming programs and maps. The library
|
||||
* Fallback: older kernels don't allow naming programs and maps. The library
|
||||
automatically detects support for names, and omits them during load if
|
||||
necessary. This works since name is primarily a debug aid.
|
||||
|
||||
|
@ -68,7 +68,7 @@ enabled. There are multiple ways the library deals with that:
|
|||
Once program and map objects are loaded they expose the kernel's low-level API,
|
||||
e.g. `NextKey`. Often this API is awkward to use in Go, so there are safer
|
||||
wrappers on top of the low-level API, like `MapIterator`. The low-level API is
|
||||
useful as an out when our higher-level API doesn't support a particular use case.
|
||||
useful when our higher-level API doesn't support a particular use case.
|
||||
|
||||
Links
|
||||
---
|
||||
|
@ -78,3 +78,9 @@ tend to use bpf_link to do so. Older hooks unfortunately use a combination of
|
|||
syscalls, netlink messages, etc. Adding support for a new link type should not
|
||||
pull in large dependencies like netlink, so XDP programs or tracepoints are
|
||||
out of scope.
|
||||
|
||||
Each bpf_link_type has one corresponding Go type, e.g. `link.tracing` corresponds
|
||||
to BPF_LINK_TRACING. In general, these types should be unexported as long as they
|
||||
don't export methods outside of the Link interface. Each Go type may have multiple
|
||||
exported constructors. For example `AttachTracing` and `AttachLSM` create a
|
||||
tracing link, but are distinct functions since they may require different arguments.
|
||||
|
|
|
@ -6,8 +6,8 @@ are welcome. Please take a look at [the architecture](ARCHITECTURE.md) to get
|
|||
a better understanding for the high-level goals.
|
||||
|
||||
New features must be accompanied by tests. Before starting work on any large
|
||||
feature, please [join](https://cilium.herokuapp.com/) the
|
||||
[#libbpf-go](https://cilium.slack.com/messages/libbpf-go) channel on Slack to
|
||||
feature, please [join](https://ebpf.io/slack) the
|
||||
[#ebpf-go](https://cilium.slack.com/messages/ebpf-go) channel on Slack to
|
||||
discuss the design first.
|
||||
|
||||
When submitting pull requests, consider writing details about what problem you
|
||||
|
@ -18,6 +18,23 @@ reason about the proposed changes.
|
|||
## Running the tests
|
||||
|
||||
Many of the tests require privileges to set resource limits and load eBPF code.
|
||||
The easiest way to obtain these is to run the tests with `sudo`:
|
||||
The easiest way to obtain these is to run the tests with `sudo`.
|
||||
|
||||
To test the current package with your local kernel you can simply run:
|
||||
```
|
||||
go test -exec sudo ./...
|
||||
```
|
||||
|
||||
To test the current package with a different kernel version you can use the [run-tests.sh](run-tests.sh) script.
|
||||
It requires [virtme](https://github.com/amluto/virtme) and qemu to be installed.
|
||||
|
||||
Examples:
|
||||
|
||||
```bash
|
||||
# Run all tests on a 5.4 kernel
|
||||
./run-tests.sh 5.4
|
||||
|
||||
# Run a subset of tests:
|
||||
./run-tests.sh 5.4 go test ./link
|
||||
```
|
||||
|
||||
sudo go test ./...
|
|
@ -0,0 +1,8 @@
|
|||
# Maintainers
|
||||
|
||||
* [Lorenz Bauer]
|
||||
* [Timo Beckers] (Isovalent)
|
||||
|
||||
|
||||
[Lorenz Bauer]: https://github.com/lmb
|
||||
[Timo Beckers]: https://github.com/ti-mo
|
|
@ -1,67 +1,110 @@
|
|||
# The development version of clang is distributed as the 'clang' binary,
|
||||
# while stable/released versions have a version number attached.
|
||||
# Pin the default clang to a stable version.
|
||||
CLANG ?= clang-11
|
||||
CFLAGS := -target bpf -O2 -g -Wall -Werror $(CFLAGS)
|
||||
CLANG ?= clang-14
|
||||
STRIP ?= llvm-strip-14
|
||||
OBJCOPY ?= llvm-objcopy-14
|
||||
CFLAGS := -O2 -g -Wall -Werror $(CFLAGS)
|
||||
|
||||
CI_KERNEL_URL ?= https://github.com/cilium/ci-kernels/raw/master/
|
||||
|
||||
# Obtain an absolute path to the directory of the Makefile.
|
||||
# Assume the Makefile is in the root of the repository.
|
||||
REPODIR := $(shell dirname $(realpath $(firstword $(MAKEFILE_LIST))))
|
||||
UIDGID := $(shell stat -c '%u:%g' ${REPODIR})
|
||||
|
||||
# Prefer podman if installed, otherwise use docker.
|
||||
# Note: Setting the var at runtime will always override.
|
||||
CONTAINER_ENGINE ?= $(if $(shell command -v podman), podman, docker)
|
||||
CONTAINER_RUN_ARGS ?= $(if $(filter ${CONTAINER_ENGINE}, podman), --log-driver=none, --user "${UIDGID}")
|
||||
|
||||
IMAGE := $(shell cat ${REPODIR}/testdata/docker/IMAGE)
|
||||
VERSION := $(shell cat ${REPODIR}/testdata/docker/VERSION)
|
||||
|
||||
|
||||
# clang <8 doesn't tag relocs properly (STT_NOTYPE)
|
||||
# clang 9 is the first version emitting BTF
|
||||
TARGETS := \
|
||||
testdata/loader-clang-7 \
|
||||
testdata/loader-clang-9 \
|
||||
testdata/loader-clang-11 \
|
||||
testdata/loader-$(CLANG) \
|
||||
testdata/btf_map_init \
|
||||
testdata/invalid_map \
|
||||
testdata/raw_tracepoint \
|
||||
testdata/invalid_map_static \
|
||||
testdata/initialized_btf_map \
|
||||
testdata/invalid_btf_map_init \
|
||||
testdata/strings \
|
||||
internal/btf/testdata/relocs
|
||||
testdata/freplace \
|
||||
testdata/iproute2_map_compat \
|
||||
testdata/map_spin_lock \
|
||||
testdata/subprog_reloc \
|
||||
testdata/fwd_decl \
|
||||
btf/testdata/relocs \
|
||||
btf/testdata/relocs_read \
|
||||
btf/testdata/relocs_read_tgt
|
||||
|
||||
.PHONY: all clean docker-all docker-shell
|
||||
.PHONY: all clean container-all container-shell generate
|
||||
|
||||
.DEFAULT_TARGET = docker-all
|
||||
.DEFAULT_TARGET = container-all
|
||||
|
||||
# Build all ELF binaries using a Dockerized LLVM toolchain.
|
||||
docker-all:
|
||||
docker run --rm --user "${UIDGID}" \
|
||||
# Build all ELF binaries using a containerized LLVM toolchain.
|
||||
container-all:
|
||||
${CONTAINER_ENGINE} run --rm ${CONTAINER_RUN_ARGS} \
|
||||
-v "${REPODIR}":/ebpf -w /ebpf --env MAKEFLAGS \
|
||||
--env CFLAGS="-fdebug-prefix-map=/ebpf=." \
|
||||
--env HOME="/tmp" \
|
||||
"${IMAGE}:${VERSION}" \
|
||||
make all
|
||||
$(MAKE) all
|
||||
|
||||
# (debug) Drop the user into a shell inside the Docker container as root.
|
||||
docker-shell:
|
||||
docker run --rm -ti \
|
||||
# (debug) Drop the user into a shell inside the container as root.
|
||||
container-shell:
|
||||
${CONTAINER_ENGINE} run --rm -ti \
|
||||
-v "${REPODIR}":/ebpf -w /ebpf \
|
||||
"${IMAGE}:${VERSION}"
|
||||
|
||||
clean:
|
||||
-$(RM) testdata/*.elf
|
||||
-$(RM) internal/btf/testdata/*.elf
|
||||
-$(RM) btf/testdata/*.elf
|
||||
|
||||
all: $(addsuffix -el.elf,$(TARGETS)) $(addsuffix -eb.elf,$(TARGETS))
|
||||
format:
|
||||
find . -type f -name "*.c" | xargs clang-format -i
|
||||
|
||||
all: format $(addsuffix -el.elf,$(TARGETS)) $(addsuffix -eb.elf,$(TARGETS)) generate
|
||||
ln -srf testdata/loader-$(CLANG)-el.elf testdata/loader-el.elf
|
||||
ln -srf testdata/loader-$(CLANG)-eb.elf testdata/loader-eb.elf
|
||||
|
||||
# $BPF_CLANG is used in go:generate invocations.
|
||||
generate: export BPF_CLANG := $(CLANG)
|
||||
generate: export BPF_CFLAGS := $(CFLAGS)
|
||||
generate:
|
||||
go generate ./cmd/bpf2go/test
|
||||
go generate ./internal/sys
|
||||
cd examples/ && go generate ./...
|
||||
|
||||
testdata/loader-%-el.elf: testdata/loader.c
|
||||
$* $(CFLAGS) -mlittle-endian -c $< -o $@
|
||||
$* $(CFLAGS) -target bpfel -c $< -o $@
|
||||
$(STRIP) -g $@
|
||||
|
||||
testdata/loader-%-eb.elf: testdata/loader.c
|
||||
$* $(CFLAGS) -mbig-endian -c $< -o $@
|
||||
$* $(CFLAGS) -target bpfeb -c $< -o $@
|
||||
$(STRIP) -g $@
|
||||
|
||||
%-el.elf: %.c
|
||||
$(CLANG) $(CFLAGS) -mlittle-endian -c $< -o $@
|
||||
$(CLANG) $(CFLAGS) -target bpfel -c $< -o $@
|
||||
$(STRIP) -g $@
|
||||
|
||||
%-eb.elf : %.c
|
||||
$(CLANG) $(CFLAGS) -mbig-endian -c $< -o $@
|
||||
$(CLANG) $(CFLAGS) -target bpfeb -c $< -o $@
|
||||
$(STRIP) -g $@
|
||||
|
||||
# Usage: make VMLINUX=/path/to/vmlinux vmlinux-btf
|
||||
.PHONY: vmlinux-btf
|
||||
vmlinux-btf: internal/btf/testdata/vmlinux-btf.gz
|
||||
internal/btf/testdata/vmlinux-btf.gz: $(VMLINUX)
|
||||
objcopy --dump-section .BTF=/dev/stdout "$<" /dev/null | gzip > "$@"
|
||||
.PHONY: generate-btf
|
||||
generate-btf: KERNEL_VERSION?=5.18
|
||||
generate-btf:
|
||||
$(eval TMP := $(shell mktemp -d))
|
||||
curl -fL "$(CI_KERNEL_URL)/linux-$(KERNEL_VERSION).bz" -o "$(TMP)/bzImage"
|
||||
./testdata/extract-vmlinux "$(TMP)/bzImage" > "$(TMP)/vmlinux"
|
||||
$(OBJCOPY) --dump-section .BTF=/dev/stdout "$(TMP)/vmlinux" /dev/null | gzip > "btf/testdata/vmlinux.btf.gz"
|
||||
curl -fL "$(CI_KERNEL_URL)/linux-$(KERNEL_VERSION)-selftests-bpf.tgz" -o "$(TMP)/selftests.tgz"
|
||||
tar -xf "$(TMP)/selftests.tgz" --to-stdout tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.ko | \
|
||||
$(OBJCOPY) --dump-section .BTF="btf/testdata/btf_testmod.btf" - /dev/null
|
||||
$(RM) -r "$(TMP)"
|
||||
|
|
|
@ -2,44 +2,60 @@
|
|||
|
||||
[![PkgGoDev](https://pkg.go.dev/badge/github.com/cilium/ebpf)](https://pkg.go.dev/github.com/cilium/ebpf)
|
||||
|
||||
![HoneyGopher](.github/images/cilium-ebpf.png)
|
||||
|
||||
eBPF is a pure Go library that provides utilities for loading, compiling, and
|
||||
debugging eBPF programs. It has minimal external dependencies and is intended to
|
||||
be used in long running processes.
|
||||
|
||||
The library is maintained by [Cloudflare](https://www.cloudflare.com) and
|
||||
[Cilium](https://www.cilium.io).
|
||||
|
||||
See [ebpf.io](https://ebpf.io) for other projects from the eBPF ecosystem.
|
||||
|
||||
## Getting Started
|
||||
|
||||
A small collection of Go and eBPF programs that serve as examples for building
|
||||
your own tools can be found under [examples/](examples/).
|
||||
|
||||
Contributions are highly encouraged, as they highlight certain use cases of
|
||||
eBPF and the library, and help shape the future of the project.
|
||||
|
||||
## Getting Help
|
||||
|
||||
Please
|
||||
[join](https://ebpf.io/slack) the
|
||||
[#ebpf-go](https://cilium.slack.com/messages/ebpf-go) channel on Slack if you
|
||||
have questions regarding the library.
|
||||
|
||||
## Packages
|
||||
|
||||
This library includes the following packages:
|
||||
|
||||
* [asm](https://pkg.go.dev/github.com/cilium/ebpf/asm) contains a basic
|
||||
assembler
|
||||
assembler, allowing you to write eBPF assembly instructions directly
|
||||
within your Go code. (You don't need to use this if you prefer to write your eBPF program in C.)
|
||||
* [cmd/bpf2go](https://pkg.go.dev/github.com/cilium/ebpf/cmd/bpf2go) allows
|
||||
compiling and embedding eBPF programs written in C within Go code. As well as
|
||||
compiling the C code, it auto-generates Go code for loading and manipulating
|
||||
the eBPF program and map objects.
|
||||
* [link](https://pkg.go.dev/github.com/cilium/ebpf/link) allows attaching eBPF
|
||||
to various hooks
|
||||
* [perf](https://pkg.go.dev/github.com/cilium/ebpf/perf) allows reading from a
|
||||
`PERF_EVENT_ARRAY`
|
||||
* [cmd/bpf2go](https://pkg.go.dev/github.com/cilium/ebpf/cmd/bpf2go) allows
|
||||
embedding eBPF in Go
|
||||
|
||||
The library is maintained by [Cloudflare](https://www.cloudflare.com) and
|
||||
[Cilium](https://www.cilium.io). Feel free to
|
||||
[join](https://cilium.herokuapp.com/) the
|
||||
[#libbpf-go](https://cilium.slack.com/messages/libbpf-go) channel on Slack.
|
||||
|
||||
## Current status
|
||||
|
||||
The package is production ready, but **the API is explicitly unstable right
|
||||
now**. Expect to update your code if you want to follow along.
|
||||
* [ringbuf](https://pkg.go.dev/github.com/cilium/ebpf/ringbuf) allows reading from a
|
||||
`BPF_MAP_TYPE_RINGBUF` map
|
||||
* [features](https://pkg.go.dev/github.com/cilium/ebpf/features) implements the equivalent
|
||||
of `bpftool feature probe` for discovering BPF-related kernel features using native Go.
|
||||
* [rlimit](https://pkg.go.dev/github.com/cilium/ebpf/rlimit) provides a convenient API to lift
|
||||
the `RLIMIT_MEMLOCK` constraint on kernels before 5.11.
|
||||
|
||||
## Requirements
|
||||
|
||||
* A version of Go that is [supported by
|
||||
upstream](https://golang.org/doc/devel/release.html#policy)
|
||||
* Linux 4.9, 4.19 or 5.4 (versions in-between should work, but are not tested)
|
||||
|
||||
## Useful resources
|
||||
|
||||
* [eBPF.io](https://ebpf.io) (recommended)
|
||||
* [Cilium eBPF documentation](https://docs.cilium.io/en/latest/bpf/#bpf-guide)
|
||||
(recommended)
|
||||
* [Linux documentation on
|
||||
BPF](https://www.kernel.org/doc/html/latest/networking/filter.html)
|
||||
* [eBPF features by Linux
|
||||
version](https://github.com/iovisor/bcc/blob/master/docs/kernel-versions.md)
|
||||
* Linux >= 4.9. CI is run against kernel.org LTS releases. 4.4 should work but is
|
||||
not tested against.
|
||||
|
||||
## Regenerating Testdata
|
||||
|
||||
|
@ -47,8 +63,15 @@ Run `make` in the root of this repository to rebuild testdata in all
|
|||
subpackages. This requires Docker, as it relies on a standardized build
|
||||
environment to keep the build output stable.
|
||||
|
||||
It is possible to regenerate data using Podman by overriding the `CONTAINER_*`
|
||||
variables: `CONTAINER_ENGINE=podman CONTAINER_RUN_ARGS= make`.
|
||||
|
||||
The toolchain image build files are kept in [testdata/docker/](testdata/docker/).
|
||||
|
||||
## License
|
||||
|
||||
MIT
|
||||
|
||||
### eBPF Gopher
|
||||
|
||||
The eBPF honeygopher is based on the Go gopher designed by Renee French.
|
||||
|
|
|
@ -5,9 +5,13 @@ package asm
|
|||
// BuiltinFunc is a built-in eBPF function.
|
||||
type BuiltinFunc int32
|
||||
|
||||
func (_ BuiltinFunc) Max() BuiltinFunc {
|
||||
return maxBuiltinFunc - 1
|
||||
}
|
||||
|
||||
// eBPF built-in functions
|
||||
//
|
||||
// You can renegerate this list using the following gawk script:
|
||||
// You can regenerate this list using the following gawk script:
|
||||
//
|
||||
// /FN\(.+\),/ {
|
||||
// match($1, /\((.+)\)/, r)
|
||||
|
@ -132,6 +136,101 @@ const (
|
|||
FnSkStorageDelete
|
||||
FnSendSignal
|
||||
FnTcpGenSyncookie
|
||||
FnSkbOutput
|
||||
FnProbeReadUser
|
||||
FnProbeReadKernel
|
||||
FnProbeReadUserStr
|
||||
FnProbeReadKernelStr
|
||||
FnTcpSendAck
|
||||
FnSendSignalThread
|
||||
FnJiffies64
|
||||
FnReadBranchRecords
|
||||
FnGetNsCurrentPidTgid
|
||||
FnXdpOutput
|
||||
FnGetNetnsCookie
|
||||
FnGetCurrentAncestorCgroupId
|
||||
FnSkAssign
|
||||
FnKtimeGetBootNs
|
||||
FnSeqPrintf
|
||||
FnSeqWrite
|
||||
FnSkCgroupId
|
||||
FnSkAncestorCgroupId
|
||||
FnRingbufOutput
|
||||
FnRingbufReserve
|
||||
FnRingbufSubmit
|
||||
FnRingbufDiscard
|
||||
FnRingbufQuery
|
||||
FnCsumLevel
|
||||
FnSkcToTcp6Sock
|
||||
FnSkcToTcpSock
|
||||
FnSkcToTcpTimewaitSock
|
||||
FnSkcToTcpRequestSock
|
||||
FnSkcToUdp6Sock
|
||||
FnGetTaskStack
|
||||
FnLoadHdrOpt
|
||||
FnStoreHdrOpt
|
||||
FnReserveHdrOpt
|
||||
FnInodeStorageGet
|
||||
FnInodeStorageDelete
|
||||
FnDPath
|
||||
FnCopyFromUser
|
||||
FnSnprintfBtf
|
||||
FnSeqPrintfBtf
|
||||
FnSkbCgroupClassid
|
||||
FnRedirectNeigh
|
||||
FnPerCpuPtr
|
||||
FnThisCpuPtr
|
||||
FnRedirectPeer
|
||||
FnTaskStorageGet
|
||||
FnTaskStorageDelete
|
||||
FnGetCurrentTaskBtf
|
||||
FnBprmOptsSet
|
||||
FnKtimeGetCoarseNs
|
||||
FnImaInodeHash
|
||||
FnSockFromFile
|
||||
FnCheckMtu
|
||||
FnForEachMapElem
|
||||
FnSnprintf
|
||||
FnSysBpf
|
||||
FnBtfFindByNameKind
|
||||
FnSysClose
|
||||
FnTimerInit
|
||||
FnTimerSetCallback
|
||||
FnTimerStart
|
||||
FnTimerCancel
|
||||
FnGetFuncIp
|
||||
FnGetAttachCookie
|
||||
FnTaskPtRegs
|
||||
FnGetBranchSnapshot
|
||||
FnTraceVprintk
|
||||
FnSkcToUnixSock
|
||||
FnKallsymsLookupName
|
||||
FnFindVma
|
||||
FnLoop
|
||||
FnStrncmp
|
||||
FnGetFuncArg
|
||||
FnGetFuncRet
|
||||
FnGetFuncArgCnt
|
||||
FnGetRetval
|
||||
FnSetRetval
|
||||
FnXdpGetBuffLen
|
||||
FnXdpLoadBytes
|
||||
FnXdpStoreBytes
|
||||
FnCopyFromUserTask
|
||||
FnSkbSetTstamp
|
||||
FnImaFileHash
|
||||
FnKptrXchg
|
||||
FnMapLookupPercpuElem
|
||||
FnSkcToMptcpSock
|
||||
FnDynptrFromMem
|
||||
FnRingbufReserveDynptr
|
||||
FnRingbufSubmitDynptr
|
||||
FnRingbufDiscardDynptr
|
||||
FnDynptrRead
|
||||
FnDynptrWrite
|
||||
FnDynptrData
|
||||
|
||||
maxBuiltinFunc
|
||||
)
|
||||
|
||||
// Call emits a function call.
|
||||
|
|
|
@ -119,11 +119,105 @@ func _() {
|
|||
_ = x[FnSkStorageDelete-108]
|
||||
_ = x[FnSendSignal-109]
|
||||
_ = x[FnTcpGenSyncookie-110]
|
||||
_ = x[FnSkbOutput-111]
|
||||
_ = x[FnProbeReadUser-112]
|
||||
_ = x[FnProbeReadKernel-113]
|
||||
_ = x[FnProbeReadUserStr-114]
|
||||
_ = x[FnProbeReadKernelStr-115]
|
||||
_ = x[FnTcpSendAck-116]
|
||||
_ = x[FnSendSignalThread-117]
|
||||
_ = x[FnJiffies64-118]
|
||||
_ = x[FnReadBranchRecords-119]
|
||||
_ = x[FnGetNsCurrentPidTgid-120]
|
||||
_ = x[FnXdpOutput-121]
|
||||
_ = x[FnGetNetnsCookie-122]
|
||||
_ = x[FnGetCurrentAncestorCgroupId-123]
|
||||
_ = x[FnSkAssign-124]
|
||||
_ = x[FnKtimeGetBootNs-125]
|
||||
_ = x[FnSeqPrintf-126]
|
||||
_ = x[FnSeqWrite-127]
|
||||
_ = x[FnSkCgroupId-128]
|
||||
_ = x[FnSkAncestorCgroupId-129]
|
||||
_ = x[FnRingbufOutput-130]
|
||||
_ = x[FnRingbufReserve-131]
|
||||
_ = x[FnRingbufSubmit-132]
|
||||
_ = x[FnRingbufDiscard-133]
|
||||
_ = x[FnRingbufQuery-134]
|
||||
_ = x[FnCsumLevel-135]
|
||||
_ = x[FnSkcToTcp6Sock-136]
|
||||
_ = x[FnSkcToTcpSock-137]
|
||||
_ = x[FnSkcToTcpTimewaitSock-138]
|
||||
_ = x[FnSkcToTcpRequestSock-139]
|
||||
_ = x[FnSkcToUdp6Sock-140]
|
||||
_ = x[FnGetTaskStack-141]
|
||||
_ = x[FnLoadHdrOpt-142]
|
||||
_ = x[FnStoreHdrOpt-143]
|
||||
_ = x[FnReserveHdrOpt-144]
|
||||
_ = x[FnInodeStorageGet-145]
|
||||
_ = x[FnInodeStorageDelete-146]
|
||||
_ = x[FnDPath-147]
|
||||
_ = x[FnCopyFromUser-148]
|
||||
_ = x[FnSnprintfBtf-149]
|
||||
_ = x[FnSeqPrintfBtf-150]
|
||||
_ = x[FnSkbCgroupClassid-151]
|
||||
_ = x[FnRedirectNeigh-152]
|
||||
_ = x[FnPerCpuPtr-153]
|
||||
_ = x[FnThisCpuPtr-154]
|
||||
_ = x[FnRedirectPeer-155]
|
||||
_ = x[FnTaskStorageGet-156]
|
||||
_ = x[FnTaskStorageDelete-157]
|
||||
_ = x[FnGetCurrentTaskBtf-158]
|
||||
_ = x[FnBprmOptsSet-159]
|
||||
_ = x[FnKtimeGetCoarseNs-160]
|
||||
_ = x[FnImaInodeHash-161]
|
||||
_ = x[FnSockFromFile-162]
|
||||
_ = x[FnCheckMtu-163]
|
||||
_ = x[FnForEachMapElem-164]
|
||||
_ = x[FnSnprintf-165]
|
||||
_ = x[FnSysBpf-166]
|
||||
_ = x[FnBtfFindByNameKind-167]
|
||||
_ = x[FnSysClose-168]
|
||||
_ = x[FnTimerInit-169]
|
||||
_ = x[FnTimerSetCallback-170]
|
||||
_ = x[FnTimerStart-171]
|
||||
_ = x[FnTimerCancel-172]
|
||||
_ = x[FnGetFuncIp-173]
|
||||
_ = x[FnGetAttachCookie-174]
|
||||
_ = x[FnTaskPtRegs-175]
|
||||
_ = x[FnGetBranchSnapshot-176]
|
||||
_ = x[FnTraceVprintk-177]
|
||||
_ = x[FnSkcToUnixSock-178]
|
||||
_ = x[FnKallsymsLookupName-179]
|
||||
_ = x[FnFindVma-180]
|
||||
_ = x[FnLoop-181]
|
||||
_ = x[FnStrncmp-182]
|
||||
_ = x[FnGetFuncArg-183]
|
||||
_ = x[FnGetFuncRet-184]
|
||||
_ = x[FnGetFuncArgCnt-185]
|
||||
_ = x[FnGetRetval-186]
|
||||
_ = x[FnSetRetval-187]
|
||||
_ = x[FnXdpGetBuffLen-188]
|
||||
_ = x[FnXdpLoadBytes-189]
|
||||
_ = x[FnXdpStoreBytes-190]
|
||||
_ = x[FnCopyFromUserTask-191]
|
||||
_ = x[FnSkbSetTstamp-192]
|
||||
_ = x[FnImaFileHash-193]
|
||||
_ = x[FnKptrXchg-194]
|
||||
_ = x[FnMapLookupPercpuElem-195]
|
||||
_ = x[FnSkcToMptcpSock-196]
|
||||
_ = x[FnDynptrFromMem-197]
|
||||
_ = x[FnRingbufReserveDynptr-198]
|
||||
_ = x[FnRingbufSubmitDynptr-199]
|
||||
_ = x[FnRingbufDiscardDynptr-200]
|
||||
_ = x[FnDynptrRead-201]
|
||||
_ = x[FnDynptrWrite-202]
|
||||
_ = x[FnDynptrData-203]
|
||||
_ = x[maxBuiltinFunc-204]
|
||||
}
|
||||
|
||||
const _BuiltinFunc_name = "FnUnspecFnMapLookupElemFnMapUpdateElemFnMapDeleteElemFnProbeReadFnKtimeGetNsFnTracePrintkFnGetPrandomU32FnGetSmpProcessorIdFnSkbStoreBytesFnL3CsumReplaceFnL4CsumReplaceFnTailCallFnCloneRedirectFnGetCurrentPidTgidFnGetCurrentUidGidFnGetCurrentCommFnGetCgroupClassidFnSkbVlanPushFnSkbVlanPopFnSkbGetTunnelKeyFnSkbSetTunnelKeyFnPerfEventReadFnRedirectFnGetRouteRealmFnPerfEventOutputFnSkbLoadBytesFnGetStackidFnCsumDiffFnSkbGetTunnelOptFnSkbSetTunnelOptFnSkbChangeProtoFnSkbChangeTypeFnSkbUnderCgroupFnGetHashRecalcFnGetCurrentTaskFnProbeWriteUserFnCurrentTaskUnderCgroupFnSkbChangeTailFnSkbPullDataFnCsumUpdateFnSetHashInvalidFnGetNumaNodeIdFnSkbChangeHeadFnXdpAdjustHeadFnProbeReadStrFnGetSocketCookieFnGetSocketUidFnSetHashFnSetsockoptFnSkbAdjustRoomFnRedirectMapFnSkRedirectMapFnSockMapUpdateFnXdpAdjustMetaFnPerfEventReadValueFnPerfProgReadValueFnGetsockoptFnOverrideReturnFnSockOpsCbFlagsSetFnMsgRedirectMapFnMsgApplyBytesFnMsgCorkBytesFnMsgPullDataFnBindFnXdpAdjustTailFnSkbGetXfrmStateFnGetStackFnSkbLoadBytesRelativeFnFibLookupFnSockHashUpdateFnMsgRedirectHashFnSkRedirectHashFnLwtPushEncapFnLwtSeg6StoreBytesFnLwtSeg6AdjustSrhFnLwtSeg6ActionFnRcRepeatFnRcKeydownFnSkbCgroupIdFnGetCurrentCgroupIdFnGetLocalStorageFnSkSelectReuseportFnSkbAncestorCgroupIdFnSkLookupTcpFnSkLookupUdpFnSkReleaseFnMapPushElemFnMapPopElemFnMapPeekElemFnMsgPushDataFnMsgPopDataFnRcPointerRelFnSpinLockFnSpinUnlockFnSkFullsockFnTcpSockFnSkbEcnSetCeFnGetListenerSockFnSkcLookupTcpFnTcpCheckSyncookieFnSysctlGetNameFnSysctlGetCurrentValueFnSysctlGetNewValueFnSysctlSetNewValueFnStrtolFnStrtoulFnSkStorageGetFnSkStorageDeleteFnSendSignalFnTcpGenSyncookie"
|
||||
const _BuiltinFunc_name = "FnUnspecFnMapLookupElemFnMapUpdateElemFnMapDeleteElemFnProbeReadFnKtimeGetNsFnTracePrintkFnGetPrandomU32FnGetSmpProcessorIdFnSkbStoreBytesFnL3CsumReplaceFnL4CsumReplaceFnTailCallFnCloneRedirectFnGetCurrentPidTgidFnGetCurrentUidGidFnGetCurrentCommFnGetCgroupClassidFnSkbVlanPushFnSkbVlanPopFnSkbGetTunnelKeyFnSkbSetTunnelKeyFnPerfEventReadFnRedirectFnGetRouteRealmFnPerfEventOutputFnSkbLoadBytesFnGetStackidFnCsumDiffFnSkbGetTunnelOptFnSkbSetTunnelOptFnSkbChangeProtoFnSkbChangeTypeFnSkbUnderCgroupFnGetHashRecalcFnGetCurrentTaskFnProbeWriteUserFnCurrentTaskUnderCgroupFnSkbChangeTailFnSkbPullDataFnCsumUpdateFnSetHashInvalidFnGetNumaNodeIdFnSkbChangeHeadFnXdpAdjustHeadFnProbeReadStrFnGetSocketCookieFnGetSocketUidFnSetHashFnSetsockoptFnSkbAdjustRoomFnRedirectMapFnSkRedirectMapFnSockMapUpdateFnXdpAdjustMetaFnPerfEventReadValueFnPerfProgReadValueFnGetsockoptFnOverrideReturnFnSockOpsCbFlagsSetFnMsgRedirectMapFnMsgApplyBytesFnMsgCorkBytesFnMsgPullDataFnBindFnXdpAdjustTailFnSkbGetXfrmStateFnGetStackFnSkbLoadBytesRelativeFnFibLookupFnSockHashUpdateFnMsgRedirectHashFnSkRedirectHashFnLwtPushEncapFnLwtSeg6StoreBytesFnLwtSeg6AdjustSrhFnLwtSeg6ActionFnRcRepeatFnRcKeydownFnSkbCgroupIdFnGetCurrentCgroupIdFnGetLocalStorageFnSkSelectReuseportFnSkbAncestorCgroupIdFnSkLookupTcpFnSkLookupUdpFnSkReleaseFnMapPushElemFnMapPopElemFnMapPeekElemFnMsgPushDataFnMsgPopDataFnRcPointerRelFnSpinLockFnSpinUnlockFnSkFullsockFnTcpSockFnSkbEcnSetCeFnGetListenerSockFnSkcLookupTcpFnTcpCheckSyncookieFnSysctlGetNameFnSysctlGetCurrentValueFnSysctlGetNewValueFnSysctlSetNewValueFnStrtolFnStrtoulFnSkStorageGetFnSkStorageDeleteFnSendSignalFnTcpGenSyncookieFnSkbOutputFnProbeReadUserFnProbeReadKernelFnProbeReadUserStrFnProbeReadKernelStrFnTcpSendAckFnSendSignalThreadFnJiffies64FnReadBranchRecordsFnGetNsCurrentPidTgidFnXdpOutputFnGetNetnsCookieFnGetCurrentAncestorCgroupIdFnSkAssignFnKtimeGetBootNsFnSeqPrintfFnSeqWriteFnSkCgroupIdFnSkAncestorCgroupIdFnRingbufOutputFnRingbufReserveFnRingbufSubmitFnRingbufDiscardFnRingbufQueryFnCsumLevelFnSkcToTcp6SockFnSkcToTcpSockFnSkcToTcpTimewaitSockFnSkcToTcpRequestSockFnSkcToUdp6SockFnGetTaskStackFnLoadHdrOptFnStoreHdrOptFnReserveHdrOptFnInodeStorageGetFnInodeStorageDeleteFnDPathFnCopyFromUserFnSnprintfBtfFnSeqPrintfBtfFnSkbCgroupClassidFnRedirectNeighFnPerCpuPtrFnThisCpuPtrFnRedirectPeerFnTaskStorageGetFnTaskStorageDeleteFnGetCurrentTaskBtfFnBprmOptsSetFnKtimeGetCoarseNsFnImaInodeHashFnSockFromFileFnCheckMtuFnForEachMapElemFnSnprintfFnSysBpfFnBtfFindByNameKindFnSysCloseFnTimerInitFnTimerSetCallbackFnTimerStartFnTimerCancelFnGetFuncIpFnGetAttachCookieFnTaskPtRegsFnGetBranchSnapshotFnTraceVprintkFnSkcToUnixSockFnKallsymsLookupNameFnFindVmaFnLoopFnStrncmpFnGetFuncArgFnGetFuncRetFnGetFuncArgCntFnGetRetvalFnSetRetvalFnXdpGetBuffLenFnXdpLoadBytesFnXdpStoreBytesFnCopyFromUserTaskFnSkbSetTstampFnImaFileHashFnKptrXchgFnMapLookupPercpuElemFnSkcToMptcpSockFnDynptrFromMemFnRingbufReserveDynptrFnRingbufSubmitDynptrFnRingbufDiscardDynptrFnDynptrReadFnDynptrWriteFnDynptrDatamaxBuiltinFunc"
|
||||
|
||||
var _BuiltinFunc_index = [...]uint16{0, 8, 23, 38, 53, 64, 76, 89, 104, 123, 138, 153, 168, 178, 193, 212, 230, 246, 264, 277, 289, 306, 323, 338, 348, 363, 380, 394, 406, 416, 433, 450, 466, 481, 497, 512, 528, 544, 568, 583, 596, 608, 624, 639, 654, 669, 683, 700, 714, 723, 735, 750, 763, 778, 793, 808, 828, 847, 859, 875, 894, 910, 925, 939, 952, 958, 973, 990, 1000, 1022, 1033, 1049, 1066, 1082, 1096, 1115, 1133, 1148, 1158, 1169, 1182, 1202, 1219, 1238, 1259, 1272, 1285, 1296, 1309, 1321, 1334, 1347, 1359, 1373, 1383, 1395, 1407, 1416, 1429, 1446, 1460, 1479, 1494, 1517, 1536, 1555, 1563, 1572, 1586, 1603, 1615, 1632}
|
||||
var _BuiltinFunc_index = [...]uint16{0, 8, 23, 38, 53, 64, 76, 89, 104, 123, 138, 153, 168, 178, 193, 212, 230, 246, 264, 277, 289, 306, 323, 338, 348, 363, 380, 394, 406, 416, 433, 450, 466, 481, 497, 512, 528, 544, 568, 583, 596, 608, 624, 639, 654, 669, 683, 700, 714, 723, 735, 750, 763, 778, 793, 808, 828, 847, 859, 875, 894, 910, 925, 939, 952, 958, 973, 990, 1000, 1022, 1033, 1049, 1066, 1082, 1096, 1115, 1133, 1148, 1158, 1169, 1182, 1202, 1219, 1238, 1259, 1272, 1285, 1296, 1309, 1321, 1334, 1347, 1359, 1373, 1383, 1395, 1407, 1416, 1429, 1446, 1460, 1479, 1494, 1517, 1536, 1555, 1563, 1572, 1586, 1603, 1615, 1632, 1643, 1658, 1675, 1693, 1713, 1725, 1743, 1754, 1773, 1794, 1805, 1821, 1849, 1859, 1875, 1886, 1896, 1908, 1928, 1943, 1959, 1974, 1990, 2004, 2015, 2030, 2044, 2066, 2087, 2102, 2116, 2128, 2141, 2156, 2173, 2193, 2200, 2214, 2227, 2241, 2259, 2274, 2285, 2297, 2311, 2327, 2346, 2365, 2378, 2396, 2410, 2424, 2434, 2450, 2460, 2468, 2487, 2497, 2508, 2526, 2538, 2551, 2562, 2579, 2591, 2610, 2624, 2639, 2659, 2668, 2674, 2683, 2695, 2707, 2722, 2733, 2744, 2759, 2773, 2788, 2806, 2820, 2833, 2843, 2864, 2880, 2895, 2917, 2938, 2960, 2972, 2985, 2997, 3011}
|
||||
|
||||
func (i BuiltinFunc) String() string {
|
||||
if i < 0 || i >= BuiltinFunc(len(_BuiltinFunc_index)-1) {
|
||||
|
|
|
@ -8,8 +8,10 @@ import (
|
|||
"fmt"
|
||||
"io"
|
||||
"math"
|
||||
"sort"
|
||||
"strings"
|
||||
|
||||
"github.com/cilium/ebpf/internal/sys"
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
|
@ -19,6 +21,10 @@ const InstructionSize = 8
|
|||
// RawInstructionOffset is an offset in units of raw BPF instructions.
|
||||
type RawInstructionOffset uint64
|
||||
|
||||
var ErrUnreferencedSymbol = errors.New("unreferenced symbol")
|
||||
var ErrUnsatisfiedMapReference = errors.New("unsatisfied map reference")
|
||||
var ErrUnsatisfiedProgramReference = errors.New("unsatisfied program reference")
|
||||
|
||||
// Bytes returns the offset of an instruction in bytes.
|
||||
func (rio RawInstructionOffset) Bytes() uint64 {
|
||||
return uint64(rio) * InstructionSize
|
||||
|
@ -31,45 +37,52 @@ type Instruction struct {
|
|||
Src Register
|
||||
Offset int16
|
||||
Constant int64
|
||||
Reference string
|
||||
Symbol string
|
||||
}
|
||||
|
||||
// Sym creates a symbol.
|
||||
func (ins Instruction) Sym(name string) Instruction {
|
||||
ins.Symbol = name
|
||||
return ins
|
||||
// Metadata contains optional metadata about this instruction.
|
||||
Metadata Metadata
|
||||
}
|
||||
|
||||
// Unmarshal decodes a BPF instruction.
|
||||
func (ins *Instruction) Unmarshal(r io.Reader, bo binary.ByteOrder) (uint64, error) {
|
||||
var bi bpfInstruction
|
||||
err := binary.Read(r, bo, &bi)
|
||||
if err != nil {
|
||||
data := make([]byte, InstructionSize)
|
||||
if _, err := io.ReadFull(r, data); err != nil {
|
||||
return 0, err
|
||||
}
|
||||
|
||||
ins.OpCode = bi.OpCode
|
||||
ins.Offset = bi.Offset
|
||||
ins.Constant = int64(bi.Constant)
|
||||
ins.Dst, ins.Src, err = bi.Registers.Unmarshal(bo)
|
||||
if err != nil {
|
||||
return 0, fmt.Errorf("can't unmarshal registers: %s", err)
|
||||
ins.OpCode = OpCode(data[0])
|
||||
|
||||
regs := data[1]
|
||||
switch bo {
|
||||
case binary.LittleEndian:
|
||||
ins.Dst, ins.Src = Register(regs&0xF), Register(regs>>4)
|
||||
case binary.BigEndian:
|
||||
ins.Dst, ins.Src = Register(regs>>4), Register(regs&0xf)
|
||||
}
|
||||
|
||||
if !bi.OpCode.isDWordLoad() {
|
||||
ins.Offset = int16(bo.Uint16(data[2:4]))
|
||||
// Convert to int32 before widening to int64
|
||||
// to ensure the signed bit is carried over.
|
||||
ins.Constant = int64(int32(bo.Uint32(data[4:8])))
|
||||
|
||||
if !ins.OpCode.IsDWordLoad() {
|
||||
return InstructionSize, nil
|
||||
}
|
||||
|
||||
var bi2 bpfInstruction
|
||||
if err := binary.Read(r, bo, &bi2); err != nil {
|
||||
// Pull another instruction from the stream to retrieve the second
|
||||
// half of the 64-bit immediate value.
|
||||
if _, err := io.ReadFull(r, data); err != nil {
|
||||
// No Wrap, to avoid io.EOF clash
|
||||
return 0, errors.New("64bit immediate is missing second half")
|
||||
}
|
||||
if bi2.OpCode != 0 || bi2.Offset != 0 || bi2.Registers != 0 {
|
||||
|
||||
// Require that all fields other than the value are zero.
|
||||
if bo.Uint32(data[0:4]) != 0 {
|
||||
return 0, errors.New("64bit immediate has non-zero fields")
|
||||
}
|
||||
ins.Constant = int64(uint64(uint32(bi2.Constant))<<32 | uint64(uint32(bi.Constant)))
|
||||
|
||||
cons1 := uint32(ins.Constant)
|
||||
cons2 := int32(bo.Uint32(data[4:8]))
|
||||
ins.Constant = int64(cons2)<<32 | int64(cons1)
|
||||
|
||||
return 2 * InstructionSize, nil
|
||||
}
|
||||
|
@ -80,7 +93,7 @@ func (ins Instruction) Marshal(w io.Writer, bo binary.ByteOrder) (uint64, error)
|
|||
return 0, errors.New("invalid opcode")
|
||||
}
|
||||
|
||||
isDWordLoad := ins.OpCode.isDWordLoad()
|
||||
isDWordLoad := ins.OpCode.IsDWordLoad()
|
||||
|
||||
cons := int32(ins.Constant)
|
||||
if isDWordLoad {
|
||||
|
@ -93,14 +106,12 @@ func (ins Instruction) Marshal(w io.Writer, bo binary.ByteOrder) (uint64, error)
|
|||
return 0, fmt.Errorf("can't marshal registers: %s", err)
|
||||
}
|
||||
|
||||
bpfi := bpfInstruction{
|
||||
ins.OpCode,
|
||||
regs,
|
||||
ins.Offset,
|
||||
cons,
|
||||
}
|
||||
|
||||
if err := binary.Write(w, bo, &bpfi); err != nil {
|
||||
data := make([]byte, InstructionSize)
|
||||
data[0] = byte(ins.OpCode)
|
||||
data[1] = byte(regs)
|
||||
bo.PutUint16(data[2:4], uint16(ins.Offset))
|
||||
bo.PutUint32(data[4:8], uint32(cons))
|
||||
if _, err := w.Write(data); err != nil {
|
||||
return 0, err
|
||||
}
|
||||
|
||||
|
@ -108,45 +119,83 @@ func (ins Instruction) Marshal(w io.Writer, bo binary.ByteOrder) (uint64, error)
|
|||
return InstructionSize, nil
|
||||
}
|
||||
|
||||
bpfi = bpfInstruction{
|
||||
Constant: int32(ins.Constant >> 32),
|
||||
}
|
||||
|
||||
if err := binary.Write(w, bo, &bpfi); err != nil {
|
||||
// The first half of the second part of a double-wide instruction
|
||||
// must be zero. The second half carries the value.
|
||||
bo.PutUint32(data[0:4], 0)
|
||||
bo.PutUint32(data[4:8], uint32(ins.Constant>>32))
|
||||
if _, err := w.Write(data); err != nil {
|
||||
return 0, err
|
||||
}
|
||||
|
||||
return 2 * InstructionSize, nil
|
||||
}
|
||||
|
||||
// RewriteMapPtr changes an instruction to use a new map fd.
|
||||
// AssociateMap associates a Map with this Instruction.
|
||||
//
|
||||
// Returns an error if the instruction doesn't load a map.
|
||||
func (ins *Instruction) RewriteMapPtr(fd int) error {
|
||||
if !ins.OpCode.isDWordLoad() {
|
||||
return fmt.Errorf("%s is not a 64 bit load", ins.OpCode)
|
||||
}
|
||||
|
||||
if ins.Src != PseudoMapFD && ins.Src != PseudoMapValue {
|
||||
// Implicitly clears the Instruction's Reference field.
|
||||
//
|
||||
// Returns an error if the Instruction is not a map load.
|
||||
func (ins *Instruction) AssociateMap(m FDer) error {
|
||||
if !ins.IsLoadFromMap() {
|
||||
return errors.New("not a load from a map")
|
||||
}
|
||||
|
||||
ins.Metadata.Set(referenceMeta{}, nil)
|
||||
ins.Metadata.Set(mapMeta{}, m)
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// RewriteMapPtr changes an instruction to use a new map fd.
|
||||
//
|
||||
// Returns an error if the instruction doesn't load a map.
|
||||
//
|
||||
// Deprecated: use AssociateMap instead. If you cannot provide a Map,
|
||||
// wrap an fd in a type implementing FDer.
|
||||
func (ins *Instruction) RewriteMapPtr(fd int) error {
|
||||
if !ins.IsLoadFromMap() {
|
||||
return errors.New("not a load from a map")
|
||||
}
|
||||
|
||||
ins.encodeMapFD(fd)
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
func (ins *Instruction) encodeMapFD(fd int) {
|
||||
// Preserve the offset value for direct map loads.
|
||||
offset := uint64(ins.Constant) & (math.MaxUint32 << 32)
|
||||
rawFd := uint64(uint32(fd))
|
||||
ins.Constant = int64(offset | rawFd)
|
||||
return nil
|
||||
}
|
||||
|
||||
func (ins *Instruction) mapPtr() uint32 {
|
||||
return uint32(uint64(ins.Constant) & math.MaxUint32)
|
||||
// MapPtr returns the map fd for this instruction.
|
||||
//
|
||||
// The result is undefined if the instruction is not a load from a map,
|
||||
// see IsLoadFromMap.
|
||||
//
|
||||
// Deprecated: use Map() instead.
|
||||
func (ins *Instruction) MapPtr() int {
|
||||
// If there is a map associated with the instruction, return its FD.
|
||||
if fd := ins.Metadata.Get(mapMeta{}); fd != nil {
|
||||
return fd.(FDer).FD()
|
||||
}
|
||||
|
||||
// Fall back to the fd stored in the Constant field
|
||||
return ins.mapFd()
|
||||
}
|
||||
|
||||
// mapFd returns the map file descriptor stored in the 32 least significant
|
||||
// bits of ins' Constant field.
|
||||
func (ins *Instruction) mapFd() int {
|
||||
return int(int32(ins.Constant))
|
||||
}
|
||||
|
||||
// RewriteMapOffset changes the offset of a direct load from a map.
|
||||
//
|
||||
// Returns an error if the instruction is not a direct load.
|
||||
func (ins *Instruction) RewriteMapOffset(offset uint32) error {
|
||||
if !ins.OpCode.isDWordLoad() {
|
||||
if !ins.OpCode.IsDWordLoad() {
|
||||
return fmt.Errorf("%s is not a 64 bit load", ins.OpCode)
|
||||
}
|
||||
|
||||
|
@ -163,10 +212,10 @@ func (ins *Instruction) mapOffset() uint32 {
|
|||
return uint32(uint64(ins.Constant) >> 32)
|
||||
}
|
||||
|
||||
// isLoadFromMap returns true if the instruction loads from a map.
|
||||
// IsLoadFromMap returns true if the instruction loads from a map.
|
||||
//
|
||||
// This covers both loading the map pointer and direct map value loads.
|
||||
func (ins *Instruction) isLoadFromMap() bool {
|
||||
func (ins *Instruction) IsLoadFromMap() bool {
|
||||
return ins.OpCode == LoadImmOp(DWord) && (ins.Src == PseudoMapFD || ins.Src == PseudoMapValue)
|
||||
}
|
||||
|
||||
|
@ -177,6 +226,29 @@ func (ins *Instruction) IsFunctionCall() bool {
|
|||
return ins.OpCode.JumpOp() == Call && ins.Src == PseudoCall
|
||||
}
|
||||
|
||||
// IsLoadOfFunctionPointer returns true if the instruction loads a function pointer.
|
||||
func (ins *Instruction) IsLoadOfFunctionPointer() bool {
|
||||
return ins.OpCode.IsDWordLoad() && ins.Src == PseudoFunc
|
||||
}
|
||||
|
||||
// IsFunctionReference returns true if the instruction references another BPF
|
||||
// function, either by invoking a Call jump operation or by loading a function
|
||||
// pointer.
|
||||
func (ins *Instruction) IsFunctionReference() bool {
|
||||
return ins.IsFunctionCall() || ins.IsLoadOfFunctionPointer()
|
||||
}
|
||||
|
||||
// IsBuiltinCall returns true if the instruction is a built-in call, i.e. BPF helper call.
|
||||
func (ins *Instruction) IsBuiltinCall() bool {
|
||||
return ins.OpCode.JumpOp() == Call && ins.Src == R0 && ins.Dst == R0
|
||||
}
|
||||
|
||||
// IsConstantLoad returns true if the instruction loads a constant of the
|
||||
// given size.
|
||||
func (ins *Instruction) IsConstantLoad(size Size) bool {
|
||||
return ins.OpCode == LoadImmOp(size) && ins.Src == R0 && ins.Offset == 0
|
||||
}
|
||||
|
||||
// Format implements fmt.Formatter.
|
||||
func (ins Instruction) Format(f fmt.State, c rune) {
|
||||
if c != 'v' {
|
||||
|
@ -197,22 +269,31 @@ func (ins Instruction) Format(f fmt.State, c rune) {
|
|||
return
|
||||
}
|
||||
|
||||
if ins.isLoadFromMap() {
|
||||
fd := int32(ins.mapPtr())
|
||||
if ins.IsLoadFromMap() {
|
||||
fd := ins.mapFd()
|
||||
m := ins.Map()
|
||||
switch ins.Src {
|
||||
case PseudoMapFD:
|
||||
if m != nil {
|
||||
fmt.Fprintf(f, "LoadMapPtr dst: %s map: %s", ins.Dst, m)
|
||||
} else {
|
||||
fmt.Fprintf(f, "LoadMapPtr dst: %s fd: %d", ins.Dst, fd)
|
||||
}
|
||||
|
||||
case PseudoMapValue:
|
||||
if m != nil {
|
||||
fmt.Fprintf(f, "LoadMapValue dst: %s, map: %s off: %d", ins.Dst, m, ins.mapOffset())
|
||||
} else {
|
||||
fmt.Fprintf(f, "LoadMapValue dst: %s, fd: %d off: %d", ins.Dst, fd, ins.mapOffset())
|
||||
}
|
||||
}
|
||||
|
||||
goto ref
|
||||
}
|
||||
|
||||
fmt.Fprintf(f, "%v ", op)
|
||||
switch cls := op.Class(); cls {
|
||||
case LdClass, LdXClass, StClass, StXClass:
|
||||
switch cls := op.Class(); {
|
||||
case cls.isLoadOrStore():
|
||||
switch op.Mode() {
|
||||
case ImmMode:
|
||||
fmt.Fprintf(f, "dst: %s imm: %d", ins.Dst, ins.Constant)
|
||||
|
@ -226,7 +307,7 @@ func (ins Instruction) Format(f fmt.State, c rune) {
|
|||
fmt.Fprintf(f, "dst: %s src: %s", ins.Dst, ins.Src)
|
||||
}
|
||||
|
||||
case ALU64Class, ALUClass:
|
||||
case cls.IsALU():
|
||||
fmt.Fprintf(f, "dst: %s ", ins.Dst)
|
||||
if op.ALUOp() == Swap || op.Source() == ImmSource {
|
||||
fmt.Fprintf(f, "imm: %d", ins.Constant)
|
||||
|
@ -234,7 +315,7 @@ func (ins Instruction) Format(f fmt.State, c rune) {
|
|||
fmt.Fprintf(f, "src: %s", ins.Src)
|
||||
}
|
||||
|
||||
case JumpClass:
|
||||
case cls.IsJump():
|
||||
switch jop := op.JumpOp(); jop {
|
||||
case Call:
|
||||
if ins.Src == PseudoCall {
|
||||
|
@ -255,34 +336,171 @@ func (ins Instruction) Format(f fmt.State, c rune) {
|
|||
}
|
||||
|
||||
ref:
|
||||
if ins.Reference != "" {
|
||||
fmt.Fprintf(f, " <%s>", ins.Reference)
|
||||
if ins.Reference() != "" {
|
||||
fmt.Fprintf(f, " <%s>", ins.Reference())
|
||||
}
|
||||
}
|
||||
|
||||
func (ins Instruction) equal(other Instruction) bool {
|
||||
return ins.OpCode == other.OpCode &&
|
||||
ins.Dst == other.Dst &&
|
||||
ins.Src == other.Src &&
|
||||
ins.Offset == other.Offset &&
|
||||
ins.Constant == other.Constant
|
||||
}
|
||||
|
||||
// Size returns the amount of bytes ins would occupy in binary form.
|
||||
func (ins Instruction) Size() uint64 {
|
||||
return uint64(InstructionSize * ins.OpCode.rawInstructions())
|
||||
}
|
||||
|
||||
type symbolMeta struct{}
|
||||
|
||||
// WithSymbol marks the Instruction as a Symbol, which other Instructions
|
||||
// can point to using corresponding calls to WithReference.
|
||||
func (ins Instruction) WithSymbol(name string) Instruction {
|
||||
ins.Metadata.Set(symbolMeta{}, name)
|
||||
return ins
|
||||
}
|
||||
|
||||
// Sym creates a symbol.
|
||||
//
|
||||
// Deprecated: use WithSymbol instead.
|
||||
func (ins Instruction) Sym(name string) Instruction {
|
||||
return ins.WithSymbol(name)
|
||||
}
|
||||
|
||||
// Symbol returns the value ins has been marked with using WithSymbol,
|
||||
// otherwise returns an empty string. A symbol is often an Instruction
|
||||
// at the start of a function body.
|
||||
func (ins Instruction) Symbol() string {
|
||||
sym, _ := ins.Metadata.Get(symbolMeta{}).(string)
|
||||
return sym
|
||||
}
|
||||
|
||||
type referenceMeta struct{}
|
||||
|
||||
// WithReference makes ins reference another Symbol or map by name.
|
||||
func (ins Instruction) WithReference(ref string) Instruction {
|
||||
ins.Metadata.Set(referenceMeta{}, ref)
|
||||
return ins
|
||||
}
|
||||
|
||||
// Reference returns the Symbol or map name referenced by ins, if any.
|
||||
func (ins Instruction) Reference() string {
|
||||
ref, _ := ins.Metadata.Get(referenceMeta{}).(string)
|
||||
return ref
|
||||
}
|
||||
|
||||
type mapMeta struct{}
|
||||
|
||||
// Map returns the Map referenced by ins, if any.
|
||||
// An Instruction will contain a Map if e.g. it references an existing,
|
||||
// pinned map that was opened during ELF loading.
|
||||
func (ins Instruction) Map() FDer {
|
||||
fd, _ := ins.Metadata.Get(mapMeta{}).(FDer)
|
||||
return fd
|
||||
}
|
||||
|
||||
type sourceMeta struct{}
|
||||
|
||||
// WithSource adds source information about the Instruction.
|
||||
func (ins Instruction) WithSource(src fmt.Stringer) Instruction {
|
||||
ins.Metadata.Set(sourceMeta{}, src)
|
||||
return ins
|
||||
}
|
||||
|
||||
// Source returns source information about the Instruction. The field is
|
||||
// present when the compiler emits BTF line info about the Instruction and
|
||||
// usually contains the line of source code responsible for it.
|
||||
func (ins Instruction) Source() fmt.Stringer {
|
||||
str, _ := ins.Metadata.Get(sourceMeta{}).(fmt.Stringer)
|
||||
return str
|
||||
}
|
||||
|
||||
// A Comment can be passed to Instruction.WithSource to add a comment
|
||||
// to an instruction.
|
||||
type Comment string
|
||||
|
||||
func (s Comment) String() string {
|
||||
return string(s)
|
||||
}
|
||||
|
||||
// FDer represents a resource tied to an underlying file descriptor.
|
||||
// Used as a stand-in for e.g. ebpf.Map since that type cannot be
|
||||
// imported here and FD() is the only method we rely on.
|
||||
type FDer interface {
|
||||
FD() int
|
||||
}
|
||||
|
||||
// Instructions is an eBPF program.
|
||||
type Instructions []Instruction
|
||||
|
||||
// Unmarshal unmarshals an Instructions from a binary instruction stream.
|
||||
// All instructions in insns are replaced by instructions decoded from r.
|
||||
func (insns *Instructions) Unmarshal(r io.Reader, bo binary.ByteOrder) error {
|
||||
if len(*insns) > 0 {
|
||||
*insns = nil
|
||||
}
|
||||
|
||||
var offset uint64
|
||||
for {
|
||||
var ins Instruction
|
||||
n, err := ins.Unmarshal(r, bo)
|
||||
if errors.Is(err, io.EOF) {
|
||||
break
|
||||
}
|
||||
if err != nil {
|
||||
return fmt.Errorf("offset %d: %w", offset, err)
|
||||
}
|
||||
|
||||
*insns = append(*insns, ins)
|
||||
offset += n
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// Name returns the name of the function insns belongs to, if any.
|
||||
func (insns Instructions) Name() string {
|
||||
if len(insns) == 0 {
|
||||
return ""
|
||||
}
|
||||
return insns[0].Symbol()
|
||||
}
|
||||
|
||||
func (insns Instructions) String() string {
|
||||
return fmt.Sprint(insns)
|
||||
}
|
||||
|
||||
// RewriteMapPtr rewrites all loads of a specific map pointer to a new fd.
|
||||
// Size returns the amount of bytes insns would occupy in binary form.
|
||||
func (insns Instructions) Size() uint64 {
|
||||
var sum uint64
|
||||
for _, ins := range insns {
|
||||
sum += ins.Size()
|
||||
}
|
||||
return sum
|
||||
}
|
||||
|
||||
// AssociateMap updates all Instructions that Reference the given symbol
|
||||
// to point to an existing Map m instead.
|
||||
//
|
||||
// Returns an error if the symbol isn't used, see IsUnreferencedSymbol.
|
||||
func (insns Instructions) RewriteMapPtr(symbol string, fd int) error {
|
||||
// Returns ErrUnreferencedSymbol error if no references to symbol are found
|
||||
// in insns. If symbol is anything else than the symbol name of map (e.g.
|
||||
// a bpf2bpf subprogram), an error is returned.
|
||||
func (insns Instructions) AssociateMap(symbol string, m FDer) error {
|
||||
if symbol == "" {
|
||||
return errors.New("empty symbol")
|
||||
}
|
||||
|
||||
found := false
|
||||
var found bool
|
||||
for i := range insns {
|
||||
ins := &insns[i]
|
||||
if ins.Reference != symbol {
|
||||
if ins.Reference() != symbol {
|
||||
continue
|
||||
}
|
||||
|
||||
if err := ins.RewriteMapPtr(fd); err != nil {
|
||||
if err := ins.AssociateMap(m); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
|
@ -290,7 +508,40 @@ func (insns Instructions) RewriteMapPtr(symbol string, fd int) error {
|
|||
}
|
||||
|
||||
if !found {
|
||||
return &unreferencedSymbolError{symbol}
|
||||
return fmt.Errorf("symbol %s: %w", symbol, ErrUnreferencedSymbol)
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// RewriteMapPtr rewrites all loads of a specific map pointer to a new fd.
|
||||
//
|
||||
// Returns ErrUnreferencedSymbol if the symbol isn't used.
|
||||
//
|
||||
// Deprecated: use AssociateMap instead.
|
||||
func (insns Instructions) RewriteMapPtr(symbol string, fd int) error {
|
||||
if symbol == "" {
|
||||
return errors.New("empty symbol")
|
||||
}
|
||||
|
||||
var found bool
|
||||
for i := range insns {
|
||||
ins := &insns[i]
|
||||
if ins.Reference() != symbol {
|
||||
continue
|
||||
}
|
||||
|
||||
if !ins.IsLoadFromMap() {
|
||||
return errors.New("not a load from a map")
|
||||
}
|
||||
|
||||
ins.encodeMapFD(fd)
|
||||
|
||||
found = true
|
||||
}
|
||||
|
||||
if !found {
|
||||
return fmt.Errorf("symbol %s: %w", symbol, ErrUnreferencedSymbol)
|
||||
}
|
||||
|
||||
return nil
|
||||
|
@ -302,31 +553,61 @@ func (insns Instructions) SymbolOffsets() (map[string]int, error) {
|
|||
offsets := make(map[string]int)
|
||||
|
||||
for i, ins := range insns {
|
||||
if ins.Symbol == "" {
|
||||
if ins.Symbol() == "" {
|
||||
continue
|
||||
}
|
||||
|
||||
if _, ok := offsets[ins.Symbol]; ok {
|
||||
return nil, fmt.Errorf("duplicate symbol %s", ins.Symbol)
|
||||
if _, ok := offsets[ins.Symbol()]; ok {
|
||||
return nil, fmt.Errorf("duplicate symbol %s", ins.Symbol())
|
||||
}
|
||||
|
||||
offsets[ins.Symbol] = i
|
||||
offsets[ins.Symbol()] = i
|
||||
}
|
||||
|
||||
return offsets, nil
|
||||
}
|
||||
|
||||
// FunctionReferences returns a set of symbol names these Instructions make
|
||||
// bpf-to-bpf calls to.
|
||||
func (insns Instructions) FunctionReferences() []string {
|
||||
calls := make(map[string]struct{})
|
||||
for _, ins := range insns {
|
||||
if ins.Constant != -1 {
|
||||
// BPF-to-BPF calls have -1 constants.
|
||||
continue
|
||||
}
|
||||
|
||||
if ins.Reference() == "" {
|
||||
continue
|
||||
}
|
||||
|
||||
if !ins.IsFunctionReference() {
|
||||
continue
|
||||
}
|
||||
|
||||
calls[ins.Reference()] = struct{}{}
|
||||
}
|
||||
|
||||
result := make([]string, 0, len(calls))
|
||||
for call := range calls {
|
||||
result = append(result, call)
|
||||
}
|
||||
|
||||
sort.Strings(result)
|
||||
return result
|
||||
}
|
||||
|
||||
// ReferenceOffsets returns the set of references and their offset in
|
||||
// the instructions.
|
||||
func (insns Instructions) ReferenceOffsets() map[string][]int {
|
||||
offsets := make(map[string][]int)
|
||||
|
||||
for i, ins := range insns {
|
||||
if ins.Reference == "" {
|
||||
if ins.Reference() == "" {
|
||||
continue
|
||||
}
|
||||
|
||||
offsets[ins.Reference] = append(offsets[ins.Reference], i)
|
||||
offsets[ins.Reference()] = append(offsets[ins.Reference()], i)
|
||||
}
|
||||
|
||||
return offsets
|
||||
|
@ -337,7 +618,7 @@ func (insns Instructions) ReferenceOffsets() map[string][]int {
|
|||
// You can control indentation of symbols by
|
||||
// specifying a width. Setting a precision controls the indentation of
|
||||
// instructions.
|
||||
// The default character is a tab, which can be overriden by specifying
|
||||
// The default character is a tab, which can be overridden by specifying
|
||||
// the ' ' space flag.
|
||||
func (insns Instructions) Format(f fmt.State, c rune) {
|
||||
if c != 's' && c != 'v' {
|
||||
|
@ -377,20 +658,36 @@ func (insns Instructions) Format(f fmt.State, c rune) {
|
|||
|
||||
iter := insns.Iterate()
|
||||
for iter.Next() {
|
||||
if iter.Ins.Symbol != "" {
|
||||
fmt.Fprintf(f, "%s%s:\n", symIndent, iter.Ins.Symbol)
|
||||
if iter.Ins.Symbol() != "" {
|
||||
fmt.Fprintf(f, "%s%s:\n", symIndent, iter.Ins.Symbol())
|
||||
}
|
||||
if src := iter.Ins.Source(); src != nil {
|
||||
line := strings.TrimSpace(src.String())
|
||||
if line != "" {
|
||||
fmt.Fprintf(f, "%s%*s; %s\n", indent, offsetWidth, " ", line)
|
||||
}
|
||||
}
|
||||
fmt.Fprintf(f, "%s%*d: %v\n", indent, offsetWidth, iter.Offset, iter.Ins)
|
||||
}
|
||||
|
||||
return
|
||||
}
|
||||
|
||||
// Marshal encodes a BPF program into the kernel format.
|
||||
//
|
||||
// insns may be modified if there are unresolved jumps or bpf2bpf calls.
|
||||
//
|
||||
// Returns ErrUnsatisfiedProgramReference if there is a Reference Instruction
|
||||
// without a matching Symbol Instruction within insns.
|
||||
func (insns Instructions) Marshal(w io.Writer, bo binary.ByteOrder) error {
|
||||
if err := insns.encodeFunctionReferences(); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
if err := insns.encodeMapPointers(); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
for i, ins := range insns {
|
||||
_, err := ins.Marshal(w, bo)
|
||||
if err != nil {
|
||||
if _, err := ins.Marshal(w, bo); err != nil {
|
||||
return fmt.Errorf("instruction %d: %w", i, err)
|
||||
}
|
||||
}
|
||||
|
@ -405,7 +702,7 @@ func (insns Instructions) Marshal(w io.Writer, bo binary.ByteOrder) error {
|
|||
func (insns Instructions) Tag(bo binary.ByteOrder) (string, error) {
|
||||
h := sha1.New()
|
||||
for i, ins := range insns {
|
||||
if ins.isLoadFromMap() {
|
||||
if ins.IsLoadFromMap() {
|
||||
ins.Constant = 0
|
||||
}
|
||||
_, err := ins.Marshal(h, bo)
|
||||
|
@ -416,6 +713,95 @@ func (insns Instructions) Tag(bo binary.ByteOrder) (string, error) {
|
|||
return hex.EncodeToString(h.Sum(nil)[:unix.BPF_TAG_SIZE]), nil
|
||||
}
|
||||
|
||||
// encodeFunctionReferences populates the Offset (or Constant, depending on
|
||||
// the instruction type) field of instructions with a Reference field to point
|
||||
// to the offset of the corresponding instruction with a matching Symbol field.
|
||||
//
|
||||
// Only Reference Instructions that are either jumps or BPF function references
|
||||
// (calls or function pointer loads) are populated.
|
||||
//
|
||||
// Returns ErrUnsatisfiedProgramReference if there is a Reference Instruction
|
||||
// without at least one corresponding Symbol Instruction within insns.
|
||||
func (insns Instructions) encodeFunctionReferences() error {
|
||||
// Index the offsets of instructions tagged as a symbol.
|
||||
symbolOffsets := make(map[string]RawInstructionOffset)
|
||||
iter := insns.Iterate()
|
||||
for iter.Next() {
|
||||
ins := iter.Ins
|
||||
|
||||
if ins.Symbol() == "" {
|
||||
continue
|
||||
}
|
||||
|
||||
if _, ok := symbolOffsets[ins.Symbol()]; ok {
|
||||
return fmt.Errorf("duplicate symbol %s", ins.Symbol())
|
||||
}
|
||||
|
||||
symbolOffsets[ins.Symbol()] = iter.Offset
|
||||
}
|
||||
|
||||
// Find all instructions tagged as references to other symbols.
|
||||
// Depending on the instruction type, populate their constant or offset
|
||||
// fields to point to the symbol they refer to within the insn stream.
|
||||
iter = insns.Iterate()
|
||||
for iter.Next() {
|
||||
i := iter.Index
|
||||
offset := iter.Offset
|
||||
ins := iter.Ins
|
||||
|
||||
if ins.Reference() == "" {
|
||||
continue
|
||||
}
|
||||
|
||||
switch {
|
||||
case ins.IsFunctionReference() && ins.Constant == -1:
|
||||
symOffset, ok := symbolOffsets[ins.Reference()]
|
||||
if !ok {
|
||||
return fmt.Errorf("%s at insn %d: symbol %q: %w", ins.OpCode, i, ins.Reference(), ErrUnsatisfiedProgramReference)
|
||||
}
|
||||
|
||||
ins.Constant = int64(symOffset - offset - 1)
|
||||
|
||||
case ins.OpCode.Class().IsJump() && ins.Offset == -1:
|
||||
symOffset, ok := symbolOffsets[ins.Reference()]
|
||||
if !ok {
|
||||
return fmt.Errorf("%s at insn %d: symbol %q: %w", ins.OpCode, i, ins.Reference(), ErrUnsatisfiedProgramReference)
|
||||
}
|
||||
|
||||
ins.Offset = int16(symOffset - offset - 1)
|
||||
}
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// encodeMapPointers finds all Map Instructions and encodes their FDs
|
||||
// into their Constant fields.
|
||||
func (insns Instructions) encodeMapPointers() error {
|
||||
iter := insns.Iterate()
|
||||
for iter.Next() {
|
||||
ins := iter.Ins
|
||||
|
||||
if !ins.IsLoadFromMap() {
|
||||
continue
|
||||
}
|
||||
|
||||
m := ins.Map()
|
||||
if m == nil {
|
||||
continue
|
||||
}
|
||||
|
||||
fd := m.FD()
|
||||
if fd < 0 {
|
||||
return fmt.Errorf("map %s: %w", m, sys.ErrClosedFd)
|
||||
}
|
||||
|
||||
ins.encodeMapFD(m.FD())
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// Iterate allows iterating a BPF program while keeping track of
|
||||
// various offsets.
|
||||
//
|
||||
|
@ -451,13 +837,6 @@ func (iter *InstructionIterator) Next() bool {
|
|||
return true
|
||||
}
|
||||
|
||||
type bpfInstruction struct {
|
||||
OpCode OpCode
|
||||
Registers bpfRegisters
|
||||
Offset int16
|
||||
Constant int32
|
||||
}
|
||||
|
||||
type bpfRegisters uint8
|
||||
|
||||
func newBPFRegisters(dst, src Register, bo binary.ByteOrder) (bpfRegisters, error) {
|
||||
|
@ -471,28 +850,10 @@ func newBPFRegisters(dst, src Register, bo binary.ByteOrder) (bpfRegisters, erro
|
|||
}
|
||||
}
|
||||
|
||||
func (r bpfRegisters) Unmarshal(bo binary.ByteOrder) (dst, src Register, err error) {
|
||||
switch bo {
|
||||
case binary.LittleEndian:
|
||||
return Register(r & 0xF), Register(r >> 4), nil
|
||||
case binary.BigEndian:
|
||||
return Register(r >> 4), Register(r & 0xf), nil
|
||||
default:
|
||||
return 0, 0, fmt.Errorf("unrecognized ByteOrder %T", bo)
|
||||
}
|
||||
}
|
||||
|
||||
type unreferencedSymbolError struct {
|
||||
symbol string
|
||||
}
|
||||
|
||||
func (use *unreferencedSymbolError) Error() string {
|
||||
return fmt.Sprintf("unreferenced symbol %s", use.symbol)
|
||||
}
|
||||
|
||||
// IsUnreferencedSymbol returns true if err was caused by
|
||||
// an unreferenced symbol.
|
||||
//
|
||||
// Deprecated: use errors.Is(err, asm.ErrUnreferencedSymbol).
|
||||
func IsUnreferencedSymbol(err error) bool {
|
||||
_, ok := err.(*unreferencedSymbolError)
|
||||
return ok
|
||||
return errors.Is(err, ErrUnreferencedSymbol)
|
||||
}
|
||||
|
|
|
@ -60,34 +60,54 @@ func (op JumpOp) Op(source Source) OpCode {
|
|||
return OpCode(JumpClass).SetJumpOp(op).SetSource(source)
|
||||
}
|
||||
|
||||
// Imm compares dst to value, and adjusts PC by offset if the condition is fulfilled.
|
||||
// Imm compares 64 bit dst to 64 bit value (sign extended), and adjusts PC by offset if the condition is fulfilled.
|
||||
func (op JumpOp) Imm(dst Register, value int32, label string) Instruction {
|
||||
if op == Exit || op == Call || op == Ja {
|
||||
return Instruction{OpCode: InvalidOpCode}
|
||||
}
|
||||
|
||||
return Instruction{
|
||||
OpCode: OpCode(JumpClass).SetJumpOp(op).SetSource(ImmSource),
|
||||
OpCode: op.opCode(JumpClass, ImmSource),
|
||||
Dst: dst,
|
||||
Offset: -1,
|
||||
Constant: int64(value),
|
||||
Reference: label,
|
||||
}
|
||||
}
|
||||
|
||||
// Reg compares dst to src, and adjusts PC by offset if the condition is fulfilled.
|
||||
func (op JumpOp) Reg(dst, src Register, label string) Instruction {
|
||||
if op == Exit || op == Call || op == Ja {
|
||||
return Instruction{OpCode: InvalidOpCode}
|
||||
}.WithReference(label)
|
||||
}
|
||||
|
||||
// Imm32 compares 32 bit dst to 32 bit value, and adjusts PC by offset if the condition is fulfilled.
|
||||
// Requires kernel 5.1.
|
||||
func (op JumpOp) Imm32(dst Register, value int32, label string) Instruction {
|
||||
return Instruction{
|
||||
OpCode: OpCode(JumpClass).SetJumpOp(op).SetSource(RegSource),
|
||||
OpCode: op.opCode(Jump32Class, ImmSource),
|
||||
Dst: dst,
|
||||
Offset: -1,
|
||||
Constant: int64(value),
|
||||
}.WithReference(label)
|
||||
}
|
||||
|
||||
// Reg compares 64 bit dst to 64 bit src, and adjusts PC by offset if the condition is fulfilled.
|
||||
func (op JumpOp) Reg(dst, src Register, label string) Instruction {
|
||||
return Instruction{
|
||||
OpCode: op.opCode(JumpClass, RegSource),
|
||||
Dst: dst,
|
||||
Src: src,
|
||||
Offset: -1,
|
||||
Reference: label,
|
||||
}.WithReference(label)
|
||||
}
|
||||
|
||||
// Reg32 compares 32 bit dst to 32 bit src, and adjusts PC by offset if the condition is fulfilled.
|
||||
// Requires kernel 5.1.
|
||||
func (op JumpOp) Reg32(dst, src Register, label string) Instruction {
|
||||
return Instruction{
|
||||
OpCode: op.opCode(Jump32Class, RegSource),
|
||||
Dst: dst,
|
||||
Src: src,
|
||||
Offset: -1,
|
||||
}.WithReference(label)
|
||||
}
|
||||
|
||||
func (op JumpOp) opCode(class Class, source Source) OpCode {
|
||||
if op == Exit || op == Call || op == Ja {
|
||||
return InvalidOpCode
|
||||
}
|
||||
|
||||
return OpCode(class).SetJumpOp(op).SetSource(source)
|
||||
}
|
||||
|
||||
// Label adjusts PC to the address of the label.
|
||||
|
@ -97,13 +117,11 @@ func (op JumpOp) Label(label string) Instruction {
|
|||
OpCode: OpCode(JumpClass).SetJumpOp(Call),
|
||||
Src: PseudoCall,
|
||||
Constant: -1,
|
||||
Reference: label,
|
||||
}
|
||||
}.WithReference(label)
|
||||
}
|
||||
|
||||
return Instruction{
|
||||
OpCode: OpCode(JumpClass).SetJumpOp(op),
|
||||
Offset: -1,
|
||||
Reference: label,
|
||||
}
|
||||
}.WithReference(label)
|
||||
}
|
||||
|
|
|
@ -111,7 +111,7 @@ func LoadMapPtr(dst Register, fd int) Instruction {
|
|||
OpCode: LoadImmOp(DWord),
|
||||
Dst: dst,
|
||||
Src: PseudoMapFD,
|
||||
Constant: int64(fd),
|
||||
Constant: int64(uint32(fd)),
|
||||
}
|
||||
}
|
||||
|
||||
|
|
|
@ -0,0 +1,80 @@
|
|||
package asm
|
||||
|
||||
// Metadata contains metadata about an instruction.
|
||||
type Metadata struct {
|
||||
head *metaElement
|
||||
}
|
||||
|
||||
type metaElement struct {
|
||||
next *metaElement
|
||||
key, value interface{}
|
||||
}
|
||||
|
||||
// Find the element containing key.
|
||||
//
|
||||
// Returns nil if there is no such element.
|
||||
func (m *Metadata) find(key interface{}) *metaElement {
|
||||
for e := m.head; e != nil; e = e.next {
|
||||
if e.key == key {
|
||||
return e
|
||||
}
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Remove an element from the linked list.
|
||||
//
|
||||
// Copies as many elements of the list as necessary to remove r, but doesn't
|
||||
// perform a full copy.
|
||||
func (m *Metadata) remove(r *metaElement) {
|
||||
current := &m.head
|
||||
for e := m.head; e != nil; e = e.next {
|
||||
if e == r {
|
||||
// We've found the element we want to remove.
|
||||
*current = e.next
|
||||
|
||||
// No need to copy the tail.
|
||||
return
|
||||
}
|
||||
|
||||
// There is another element in front of the one we want to remove.
|
||||
// We have to copy it to be able to change metaElement.next.
|
||||
cpy := &metaElement{key: e.key, value: e.value}
|
||||
*current = cpy
|
||||
current = &cpy.next
|
||||
}
|
||||
}
|
||||
|
||||
// Set a key to a value.
|
||||
//
|
||||
// If value is nil, the key is removed. Avoids modifying old metadata by
|
||||
// copying if necessary.
|
||||
func (m *Metadata) Set(key, value interface{}) {
|
||||
if e := m.find(key); e != nil {
|
||||
if e.value == value {
|
||||
// Key is present and the value is the same. Nothing to do.
|
||||
return
|
||||
}
|
||||
|
||||
// Key is present with a different value. Create a copy of the list
|
||||
// which doesn't have the element in it.
|
||||
m.remove(e)
|
||||
}
|
||||
|
||||
// m.head is now a linked list that doesn't contain key.
|
||||
if value == nil {
|
||||
return
|
||||
}
|
||||
|
||||
m.head = &metaElement{key: key, value: value, next: m.head}
|
||||
}
|
||||
|
||||
// Get the value of a key.
|
||||
//
|
||||
// Returns nil if no value with the given key is present.
|
||||
func (m *Metadata) Get(key interface{}) interface{} {
|
||||
if e := m.find(key); e != nil {
|
||||
return e.value
|
||||
}
|
||||
return nil
|
||||
}
|
|
@ -7,14 +7,6 @@ import (
|
|||
|
||||
//go:generate stringer -output opcode_string.go -type=Class
|
||||
|
||||
type encoding int
|
||||
|
||||
const (
|
||||
unknownEncoding encoding = iota
|
||||
loadOrStore
|
||||
jumpOrALU
|
||||
)
|
||||
|
||||
// Class of operations
|
||||
//
|
||||
// msb lsb
|
||||
|
@ -26,31 +18,52 @@ type Class uint8
|
|||
const classMask OpCode = 0x07
|
||||
|
||||
const (
|
||||
// LdClass load memory
|
||||
// LdClass loads immediate values into registers.
|
||||
// Also used for non-standard load operations from cBPF.
|
||||
LdClass Class = 0x00
|
||||
// LdXClass load memory from constant
|
||||
// LdXClass loads memory into registers.
|
||||
LdXClass Class = 0x01
|
||||
// StClass load register from memory
|
||||
// StClass stores immediate values to memory.
|
||||
StClass Class = 0x02
|
||||
// StXClass load register from constant
|
||||
// StXClass stores registers to memory.
|
||||
StXClass Class = 0x03
|
||||
// ALUClass arithmetic operators
|
||||
// ALUClass describes arithmetic operators.
|
||||
ALUClass Class = 0x04
|
||||
// JumpClass jump operators
|
||||
// JumpClass describes jump operators.
|
||||
JumpClass Class = 0x05
|
||||
// ALU64Class arithmetic in 64 bit mode
|
||||
// Jump32Class describes jump operators with 32-bit comparisons.
|
||||
// Requires kernel 5.1.
|
||||
Jump32Class Class = 0x06
|
||||
// ALU64Class describes arithmetic operators in 64-bit mode.
|
||||
ALU64Class Class = 0x07
|
||||
)
|
||||
|
||||
func (cls Class) encoding() encoding {
|
||||
switch cls {
|
||||
case LdClass, LdXClass, StClass, StXClass:
|
||||
return loadOrStore
|
||||
case ALU64Class, ALUClass, JumpClass:
|
||||
return jumpOrALU
|
||||
default:
|
||||
return unknownEncoding
|
||||
// IsLoad checks if this is either LdClass or LdXClass.
|
||||
func (cls Class) IsLoad() bool {
|
||||
return cls == LdClass || cls == LdXClass
|
||||
}
|
||||
|
||||
// IsStore checks if this is either StClass or StXClass.
|
||||
func (cls Class) IsStore() bool {
|
||||
return cls == StClass || cls == StXClass
|
||||
}
|
||||
|
||||
func (cls Class) isLoadOrStore() bool {
|
||||
return cls.IsLoad() || cls.IsStore()
|
||||
}
|
||||
|
||||
// IsALU checks if this is either ALUClass or ALU64Class.
|
||||
func (cls Class) IsALU() bool {
|
||||
return cls == ALUClass || cls == ALU64Class
|
||||
}
|
||||
|
||||
// IsJump checks if this is either JumpClass or Jump32Class.
|
||||
func (cls Class) IsJump() bool {
|
||||
return cls == JumpClass || cls == Jump32Class
|
||||
}
|
||||
|
||||
func (cls Class) isJumpOrALU() bool {
|
||||
return cls.IsJump() || cls.IsALU()
|
||||
}
|
||||
|
||||
// OpCode is a packed eBPF opcode.
|
||||
|
@ -69,13 +82,13 @@ const InvalidOpCode OpCode = 0xff
|
|||
// rawInstructions returns the number of BPF instructions required
|
||||
// to encode this opcode.
|
||||
func (op OpCode) rawInstructions() int {
|
||||
if op.isDWordLoad() {
|
||||
if op.IsDWordLoad() {
|
||||
return 2
|
||||
}
|
||||
return 1
|
||||
}
|
||||
|
||||
func (op OpCode) isDWordLoad() bool {
|
||||
func (op OpCode) IsDWordLoad() bool {
|
||||
return op == LoadImmOp(DWord)
|
||||
}
|
||||
|
||||
|
@ -86,7 +99,7 @@ func (op OpCode) Class() Class {
|
|||
|
||||
// Mode returns the mode for load and store operations.
|
||||
func (op OpCode) Mode() Mode {
|
||||
if op.Class().encoding() != loadOrStore {
|
||||
if !op.Class().isLoadOrStore() {
|
||||
return InvalidMode
|
||||
}
|
||||
return Mode(op & modeMask)
|
||||
|
@ -94,7 +107,7 @@ func (op OpCode) Mode() Mode {
|
|||
|
||||
// Size returns the size for load and store operations.
|
||||
func (op OpCode) Size() Size {
|
||||
if op.Class().encoding() != loadOrStore {
|
||||
if !op.Class().isLoadOrStore() {
|
||||
return InvalidSize
|
||||
}
|
||||
return Size(op & sizeMask)
|
||||
|
@ -102,7 +115,7 @@ func (op OpCode) Size() Size {
|
|||
|
||||
// Source returns the source for branch and ALU operations.
|
||||
func (op OpCode) Source() Source {
|
||||
if op.Class().encoding() != jumpOrALU || op.ALUOp() == Swap {
|
||||
if !op.Class().isJumpOrALU() || op.ALUOp() == Swap {
|
||||
return InvalidSource
|
||||
}
|
||||
return Source(op & sourceMask)
|
||||
|
@ -110,7 +123,7 @@ func (op OpCode) Source() Source {
|
|||
|
||||
// ALUOp returns the ALUOp.
|
||||
func (op OpCode) ALUOp() ALUOp {
|
||||
if op.Class().encoding() != jumpOrALU {
|
||||
if !op.Class().IsALU() {
|
||||
return InvalidALUOp
|
||||
}
|
||||
return ALUOp(op & aluMask)
|
||||
|
@ -125,18 +138,27 @@ func (op OpCode) Endianness() Endianness {
|
|||
}
|
||||
|
||||
// JumpOp returns the JumpOp.
|
||||
// Returns InvalidJumpOp if it doesn't encode a jump.
|
||||
func (op OpCode) JumpOp() JumpOp {
|
||||
if op.Class().encoding() != jumpOrALU {
|
||||
if !op.Class().IsJump() {
|
||||
return InvalidJumpOp
|
||||
}
|
||||
return JumpOp(op & jumpMask)
|
||||
|
||||
jumpOp := JumpOp(op & jumpMask)
|
||||
|
||||
// Some JumpOps are only supported by JumpClass, not Jump32Class.
|
||||
if op.Class() == Jump32Class && (jumpOp == Exit || jumpOp == Call || jumpOp == Ja) {
|
||||
return InvalidJumpOp
|
||||
}
|
||||
|
||||
return jumpOp
|
||||
}
|
||||
|
||||
// SetMode sets the mode on load and store operations.
|
||||
//
|
||||
// Returns InvalidOpCode if op is of the wrong class.
|
||||
func (op OpCode) SetMode(mode Mode) OpCode {
|
||||
if op.Class().encoding() != loadOrStore || !valid(OpCode(mode), modeMask) {
|
||||
if !op.Class().isLoadOrStore() || !valid(OpCode(mode), modeMask) {
|
||||
return InvalidOpCode
|
||||
}
|
||||
return (op & ^modeMask) | OpCode(mode)
|
||||
|
@ -146,7 +168,7 @@ func (op OpCode) SetMode(mode Mode) OpCode {
|
|||
//
|
||||
// Returns InvalidOpCode if op is of the wrong class.
|
||||
func (op OpCode) SetSize(size Size) OpCode {
|
||||
if op.Class().encoding() != loadOrStore || !valid(OpCode(size), sizeMask) {
|
||||
if !op.Class().isLoadOrStore() || !valid(OpCode(size), sizeMask) {
|
||||
return InvalidOpCode
|
||||
}
|
||||
return (op & ^sizeMask) | OpCode(size)
|
||||
|
@ -156,7 +178,7 @@ func (op OpCode) SetSize(size Size) OpCode {
|
|||
//
|
||||
// Returns InvalidOpCode if op is of the wrong class.
|
||||
func (op OpCode) SetSource(source Source) OpCode {
|
||||
if op.Class().encoding() != jumpOrALU || !valid(OpCode(source), sourceMask) {
|
||||
if !op.Class().isJumpOrALU() || !valid(OpCode(source), sourceMask) {
|
||||
return InvalidOpCode
|
||||
}
|
||||
return (op & ^sourceMask) | OpCode(source)
|
||||
|
@ -166,8 +188,7 @@ func (op OpCode) SetSource(source Source) OpCode {
|
|||
//
|
||||
// Returns InvalidOpCode if op is of the wrong class.
|
||||
func (op OpCode) SetALUOp(alu ALUOp) OpCode {
|
||||
class := op.Class()
|
||||
if (class != ALUClass && class != ALU64Class) || !valid(OpCode(alu), aluMask) {
|
||||
if !op.Class().IsALU() || !valid(OpCode(alu), aluMask) {
|
||||
return InvalidOpCode
|
||||
}
|
||||
return (op & ^aluMask) | OpCode(alu)
|
||||
|
@ -177,17 +198,25 @@ func (op OpCode) SetALUOp(alu ALUOp) OpCode {
|
|||
//
|
||||
// Returns InvalidOpCode if op is of the wrong class.
|
||||
func (op OpCode) SetJumpOp(jump JumpOp) OpCode {
|
||||
if op.Class() != JumpClass || !valid(OpCode(jump), jumpMask) {
|
||||
if !op.Class().IsJump() || !valid(OpCode(jump), jumpMask) {
|
||||
return InvalidOpCode
|
||||
}
|
||||
return (op & ^jumpMask) | OpCode(jump)
|
||||
|
||||
newOp := (op & ^jumpMask) | OpCode(jump)
|
||||
|
||||
// Check newOp is legal.
|
||||
if newOp.JumpOp() == InvalidJumpOp {
|
||||
return InvalidOpCode
|
||||
}
|
||||
|
||||
return newOp
|
||||
}
|
||||
|
||||
func (op OpCode) String() string {
|
||||
var f strings.Builder
|
||||
|
||||
switch class := op.Class(); class {
|
||||
case LdClass, LdXClass, StClass, StXClass:
|
||||
switch class := op.Class(); {
|
||||
case class.isLoadOrStore():
|
||||
f.WriteString(strings.TrimSuffix(class.String(), "Class"))
|
||||
|
||||
mode := op.Mode()
|
||||
|
@ -204,7 +233,7 @@ func (op OpCode) String() string {
|
|||
f.WriteString("B")
|
||||
}
|
||||
|
||||
case ALU64Class, ALUClass:
|
||||
case class.IsALU():
|
||||
f.WriteString(op.ALUOp().String())
|
||||
|
||||
if op.ALUOp() == Swap {
|
||||
|
@ -218,8 +247,13 @@ func (op OpCode) String() string {
|
|||
f.WriteString(strings.TrimSuffix(op.Source().String(), "Source"))
|
||||
}
|
||||
|
||||
case JumpClass:
|
||||
case class.IsJump():
|
||||
f.WriteString(op.JumpOp().String())
|
||||
|
||||
if class == Jump32Class {
|
||||
f.WriteString("32")
|
||||
}
|
||||
|
||||
if jop := op.JumpOp(); jop != Exit && jop != Call {
|
||||
f.WriteString(strings.TrimSuffix(op.Source().String(), "Source"))
|
||||
}
|
||||
|
|
|
@ -14,25 +14,17 @@ func _() {
|
|||
_ = x[StXClass-3]
|
||||
_ = x[ALUClass-4]
|
||||
_ = x[JumpClass-5]
|
||||
_ = x[Jump32Class-6]
|
||||
_ = x[ALU64Class-7]
|
||||
}
|
||||
|
||||
const (
|
||||
_Class_name_0 = "LdClassLdXClassStClassStXClassALUClassJumpClass"
|
||||
_Class_name_1 = "ALU64Class"
|
||||
)
|
||||
const _Class_name = "LdClassLdXClassStClassStXClassALUClassJumpClassJump32ClassALU64Class"
|
||||
|
||||
var (
|
||||
_Class_index_0 = [...]uint8{0, 7, 15, 22, 30, 38, 47}
|
||||
)
|
||||
var _Class_index = [...]uint8{0, 7, 15, 22, 30, 38, 47, 58, 68}
|
||||
|
||||
func (i Class) String() string {
|
||||
switch {
|
||||
case 0 <= i && i <= 5:
|
||||
return _Class_name_0[_Class_index_0[i]:_Class_index_0[i+1]]
|
||||
case i == 7:
|
||||
return _Class_name_1
|
||||
default:
|
||||
if i >= Class(len(_Class_index)-1) {
|
||||
return "Class(" + strconv.FormatInt(int64(i), 10) + ")"
|
||||
}
|
||||
return _Class_name[_Class_index[i]:_Class_index[i+1]]
|
||||
}
|
||||
|
|
|
@ -38,6 +38,7 @@ const (
|
|||
PseudoMapFD = R1 // BPF_PSEUDO_MAP_FD
|
||||
PseudoMapValue = R2 // BPF_PSEUDO_MAP_VALUE
|
||||
PseudoCall = R1 // BPF_PSEUDO_CALL
|
||||
PseudoFunc = R4 // BPF_PSEUDO_FUNC
|
||||
)
|
||||
|
||||
func (r Register) String() string {
|
||||
|
|
|
@ -0,0 +1,65 @@
|
|||
// Code generated by "stringer -type AttachType -trimprefix Attach"; DO NOT EDIT.
|
||||
|
||||
package ebpf
|
||||
|
||||
import "strconv"
|
||||
|
||||
func _() {
|
||||
// An "invalid array index" compiler error signifies that the constant values have changed.
|
||||
// Re-run the stringer command to generate them again.
|
||||
var x [1]struct{}
|
||||
_ = x[AttachNone-0]
|
||||
_ = x[AttachCGroupInetIngress-0]
|
||||
_ = x[AttachCGroupInetEgress-1]
|
||||
_ = x[AttachCGroupInetSockCreate-2]
|
||||
_ = x[AttachCGroupSockOps-3]
|
||||
_ = x[AttachSkSKBStreamParser-4]
|
||||
_ = x[AttachSkSKBStreamVerdict-5]
|
||||
_ = x[AttachCGroupDevice-6]
|
||||
_ = x[AttachSkMsgVerdict-7]
|
||||
_ = x[AttachCGroupInet4Bind-8]
|
||||
_ = x[AttachCGroupInet6Bind-9]
|
||||
_ = x[AttachCGroupInet4Connect-10]
|
||||
_ = x[AttachCGroupInet6Connect-11]
|
||||
_ = x[AttachCGroupInet4PostBind-12]
|
||||
_ = x[AttachCGroupInet6PostBind-13]
|
||||
_ = x[AttachCGroupUDP4Sendmsg-14]
|
||||
_ = x[AttachCGroupUDP6Sendmsg-15]
|
||||
_ = x[AttachLircMode2-16]
|
||||
_ = x[AttachFlowDissector-17]
|
||||
_ = x[AttachCGroupSysctl-18]
|
||||
_ = x[AttachCGroupUDP4Recvmsg-19]
|
||||
_ = x[AttachCGroupUDP6Recvmsg-20]
|
||||
_ = x[AttachCGroupGetsockopt-21]
|
||||
_ = x[AttachCGroupSetsockopt-22]
|
||||
_ = x[AttachTraceRawTp-23]
|
||||
_ = x[AttachTraceFEntry-24]
|
||||
_ = x[AttachTraceFExit-25]
|
||||
_ = x[AttachModifyReturn-26]
|
||||
_ = x[AttachLSMMac-27]
|
||||
_ = x[AttachTraceIter-28]
|
||||
_ = x[AttachCgroupInet4GetPeername-29]
|
||||
_ = x[AttachCgroupInet6GetPeername-30]
|
||||
_ = x[AttachCgroupInet4GetSockname-31]
|
||||
_ = x[AttachCgroupInet6GetSockname-32]
|
||||
_ = x[AttachXDPDevMap-33]
|
||||
_ = x[AttachCgroupInetSockRelease-34]
|
||||
_ = x[AttachXDPCPUMap-35]
|
||||
_ = x[AttachSkLookup-36]
|
||||
_ = x[AttachXDP-37]
|
||||
_ = x[AttachSkSKBVerdict-38]
|
||||
_ = x[AttachSkReuseportSelect-39]
|
||||
_ = x[AttachSkReuseportSelectOrMigrate-40]
|
||||
_ = x[AttachPerfEvent-41]
|
||||
}
|
||||
|
||||
const _AttachType_name = "NoneCGroupInetEgressCGroupInetSockCreateCGroupSockOpsSkSKBStreamParserSkSKBStreamVerdictCGroupDeviceSkMsgVerdictCGroupInet4BindCGroupInet6BindCGroupInet4ConnectCGroupInet6ConnectCGroupInet4PostBindCGroupInet6PostBindCGroupUDP4SendmsgCGroupUDP6SendmsgLircMode2FlowDissectorCGroupSysctlCGroupUDP4RecvmsgCGroupUDP6RecvmsgCGroupGetsockoptCGroupSetsockoptTraceRawTpTraceFEntryTraceFExitModifyReturnLSMMacTraceIterCgroupInet4GetPeernameCgroupInet6GetPeernameCgroupInet4GetSocknameCgroupInet6GetSocknameXDPDevMapCgroupInetSockReleaseXDPCPUMapSkLookupXDPSkSKBVerdictSkReuseportSelectSkReuseportSelectOrMigratePerfEvent"
|
||||
|
||||
var _AttachType_index = [...]uint16{0, 4, 20, 40, 53, 70, 88, 100, 112, 127, 142, 160, 178, 197, 216, 233, 250, 259, 272, 284, 301, 318, 334, 350, 360, 371, 381, 393, 399, 408, 430, 452, 474, 496, 505, 526, 535, 543, 546, 558, 575, 601, 610}
|
||||
|
||||
func (i AttachType) String() string {
|
||||
if i >= AttachType(len(_AttachType_index)-1) {
|
||||
return "AttachType(" + strconv.FormatInt(int64(i), 10) + ")"
|
||||
}
|
||||
return _AttachType_name[_AttachType_index[i]:_AttachType_index[i+1]]
|
||||
}
|
|
@ -0,0 +1,897 @@
|
|||
package btf
|
||||
|
||||
import (
|
||||
"bufio"
|
||||
"bytes"
|
||||
"debug/elf"
|
||||
"encoding/binary"
|
||||
"errors"
|
||||
"fmt"
|
||||
"io"
|
||||
"math"
|
||||
"os"
|
||||
"reflect"
|
||||
|
||||
"github.com/cilium/ebpf/internal"
|
||||
"github.com/cilium/ebpf/internal/sys"
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
const btfMagic = 0xeB9F
|
||||
|
||||
// Errors returned by BTF functions.
|
||||
var (
|
||||
ErrNotSupported = internal.ErrNotSupported
|
||||
ErrNotFound = errors.New("not found")
|
||||
ErrNoExtendedInfo = errors.New("no extended info")
|
||||
)
|
||||
|
||||
// ID represents the unique ID of a BTF object.
|
||||
type ID = sys.BTFID
|
||||
|
||||
// Spec represents decoded BTF.
|
||||
type Spec struct {
|
||||
// Data from .BTF.
|
||||
rawTypes []rawType
|
||||
strings *stringTable
|
||||
|
||||
// All types contained by the spec. For the base type, the position of
|
||||
// a type in the slice is its ID.
|
||||
types types
|
||||
|
||||
// Type IDs indexed by type.
|
||||
typeIDs map[Type]TypeID
|
||||
|
||||
// Types indexed by essential name.
|
||||
// Includes all struct flavors and types with the same name.
|
||||
namedTypes map[essentialName][]Type
|
||||
|
||||
byteOrder binary.ByteOrder
|
||||
}
|
||||
|
||||
type btfHeader struct {
|
||||
Magic uint16
|
||||
Version uint8
|
||||
Flags uint8
|
||||
HdrLen uint32
|
||||
|
||||
TypeOff uint32
|
||||
TypeLen uint32
|
||||
StringOff uint32
|
||||
StringLen uint32
|
||||
}
|
||||
|
||||
// typeStart returns the offset from the beginning of the .BTF section
|
||||
// to the start of its type entries.
|
||||
func (h *btfHeader) typeStart() int64 {
|
||||
return int64(h.HdrLen + h.TypeOff)
|
||||
}
|
||||
|
||||
// stringStart returns the offset from the beginning of the .BTF section
|
||||
// to the start of its string table.
|
||||
func (h *btfHeader) stringStart() int64 {
|
||||
return int64(h.HdrLen + h.StringOff)
|
||||
}
|
||||
|
||||
// LoadSpec opens file and calls LoadSpecFromReader on it.
|
||||
func LoadSpec(file string) (*Spec, error) {
|
||||
fh, err := os.Open(file)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
defer fh.Close()
|
||||
|
||||
return LoadSpecFromReader(fh)
|
||||
}
|
||||
|
||||
// LoadSpecFromReader reads from an ELF or a raw BTF blob.
|
||||
//
|
||||
// Returns ErrNotFound if reading from an ELF which contains no BTF. ExtInfos
|
||||
// may be nil.
|
||||
func LoadSpecFromReader(rd io.ReaderAt) (*Spec, error) {
|
||||
file, err := internal.NewSafeELFFile(rd)
|
||||
if err != nil {
|
||||
if bo := guessRawBTFByteOrder(rd); bo != nil {
|
||||
// Try to parse a naked BTF blob. This will return an error if
|
||||
// we encounter a Datasec, since we can't fix it up.
|
||||
spec, err := loadRawSpec(io.NewSectionReader(rd, 0, math.MaxInt64), bo, nil, nil)
|
||||
return spec, err
|
||||
}
|
||||
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return loadSpecFromELF(file)
|
||||
}
|
||||
|
||||
// LoadSpecAndExtInfosFromReader reads from an ELF.
|
||||
//
|
||||
// ExtInfos may be nil if the ELF doesn't contain section metadta.
|
||||
// Returns ErrNotFound if the ELF contains no BTF.
|
||||
func LoadSpecAndExtInfosFromReader(rd io.ReaderAt) (*Spec, *ExtInfos, error) {
|
||||
file, err := internal.NewSafeELFFile(rd)
|
||||
if err != nil {
|
||||
return nil, nil, err
|
||||
}
|
||||
|
||||
spec, err := loadSpecFromELF(file)
|
||||
if err != nil {
|
||||
return nil, nil, err
|
||||
}
|
||||
|
||||
extInfos, err := loadExtInfosFromELF(file, spec.types, spec.strings)
|
||||
if err != nil && !errors.Is(err, ErrNotFound) {
|
||||
return nil, nil, err
|
||||
}
|
||||
|
||||
return spec, extInfos, nil
|
||||
}
|
||||
|
||||
// variableOffsets extracts all symbols offsets from an ELF and indexes them by
|
||||
// section and variable name.
|
||||
//
|
||||
// References to variables in BTF data sections carry unsigned 32-bit offsets.
|
||||
// Some ELF symbols (e.g. in vmlinux) may point to virtual memory that is well
|
||||
// beyond this range. Since these symbols cannot be described by BTF info,
|
||||
// ignore them here.
|
||||
func variableOffsets(file *internal.SafeELFFile) (map[variable]uint32, error) {
|
||||
symbols, err := file.Symbols()
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("can't read symbols: %v", err)
|
||||
}
|
||||
|
||||
variableOffsets := make(map[variable]uint32)
|
||||
for _, symbol := range symbols {
|
||||
if idx := symbol.Section; idx >= elf.SHN_LORESERVE && idx <= elf.SHN_HIRESERVE {
|
||||
// Ignore things like SHN_ABS
|
||||
continue
|
||||
}
|
||||
|
||||
if symbol.Value > math.MaxUint32 {
|
||||
// VarSecinfo offset is u32, cannot reference symbols in higher regions.
|
||||
continue
|
||||
}
|
||||
|
||||
if int(symbol.Section) >= len(file.Sections) {
|
||||
return nil, fmt.Errorf("symbol %s: invalid section %d", symbol.Name, symbol.Section)
|
||||
}
|
||||
|
||||
secName := file.Sections[symbol.Section].Name
|
||||
variableOffsets[variable{secName, symbol.Name}] = uint32(symbol.Value)
|
||||
}
|
||||
|
||||
return variableOffsets, nil
|
||||
}
|
||||
|
||||
func loadSpecFromELF(file *internal.SafeELFFile) (*Spec, error) {
|
||||
var (
|
||||
btfSection *elf.Section
|
||||
sectionSizes = make(map[string]uint32)
|
||||
)
|
||||
|
||||
for _, sec := range file.Sections {
|
||||
switch sec.Name {
|
||||
case ".BTF":
|
||||
btfSection = sec
|
||||
default:
|
||||
if sec.Type != elf.SHT_PROGBITS && sec.Type != elf.SHT_NOBITS {
|
||||
break
|
||||
}
|
||||
|
||||
if sec.Size > math.MaxUint32 {
|
||||
return nil, fmt.Errorf("section %s exceeds maximum size", sec.Name)
|
||||
}
|
||||
|
||||
sectionSizes[sec.Name] = uint32(sec.Size)
|
||||
}
|
||||
}
|
||||
|
||||
if btfSection == nil {
|
||||
return nil, fmt.Errorf("btf: %w", ErrNotFound)
|
||||
}
|
||||
|
||||
vars, err := variableOffsets(file)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
if btfSection.ReaderAt == nil {
|
||||
return nil, fmt.Errorf("compressed BTF is not supported")
|
||||
}
|
||||
|
||||
rawTypes, rawStrings, err := parseBTF(btfSection.ReaderAt, file.ByteOrder, nil)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
err = fixupDatasec(rawTypes, rawStrings, sectionSizes, vars)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return inflateSpec(rawTypes, rawStrings, file.ByteOrder, nil)
|
||||
}
|
||||
|
||||
func loadRawSpec(btf io.ReaderAt, bo binary.ByteOrder,
|
||||
baseTypes types, baseStrings *stringTable) (*Spec, error) {
|
||||
|
||||
rawTypes, rawStrings, err := parseBTF(btf, bo, baseStrings)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return inflateSpec(rawTypes, rawStrings, bo, baseTypes)
|
||||
}
|
||||
|
||||
func inflateSpec(rawTypes []rawType, rawStrings *stringTable, bo binary.ByteOrder,
|
||||
baseTypes types) (*Spec, error) {
|
||||
|
||||
types, err := inflateRawTypes(rawTypes, baseTypes, rawStrings)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
typeIDs, typesByName := indexTypes(types, TypeID(len(baseTypes)))
|
||||
|
||||
return &Spec{
|
||||
rawTypes: rawTypes,
|
||||
namedTypes: typesByName,
|
||||
typeIDs: typeIDs,
|
||||
types: types,
|
||||
strings: rawStrings,
|
||||
byteOrder: bo,
|
||||
}, nil
|
||||
}
|
||||
|
||||
func indexTypes(types []Type, typeIDOffset TypeID) (map[Type]TypeID, map[essentialName][]Type) {
|
||||
namedTypes := 0
|
||||
for _, typ := range types {
|
||||
if typ.TypeName() != "" {
|
||||
// Do a pre-pass to figure out how big types by name has to be.
|
||||
// Most types have unique names, so it's OK to ignore essentialName
|
||||
// here.
|
||||
namedTypes++
|
||||
}
|
||||
}
|
||||
|
||||
typeIDs := make(map[Type]TypeID, len(types))
|
||||
typesByName := make(map[essentialName][]Type, namedTypes)
|
||||
|
||||
for i, typ := range types {
|
||||
if name := newEssentialName(typ.TypeName()); name != "" {
|
||||
typesByName[name] = append(typesByName[name], typ)
|
||||
}
|
||||
typeIDs[typ] = TypeID(i) + typeIDOffset
|
||||
}
|
||||
|
||||
return typeIDs, typesByName
|
||||
}
|
||||
|
||||
// LoadKernelSpec returns the current kernel's BTF information.
|
||||
//
|
||||
// Defaults to /sys/kernel/btf/vmlinux and falls back to scanning the file system
|
||||
// for vmlinux ELFs. Returns an error wrapping ErrNotSupported if BTF is not enabled.
|
||||
func LoadKernelSpec() (*Spec, error) {
|
||||
fh, err := os.Open("/sys/kernel/btf/vmlinux")
|
||||
if err == nil {
|
||||
defer fh.Close()
|
||||
|
||||
return loadRawSpec(fh, internal.NativeEndian, nil, nil)
|
||||
}
|
||||
|
||||
file, err := findVMLinux()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
defer file.Close()
|
||||
|
||||
return loadSpecFromELF(file)
|
||||
}
|
||||
|
||||
// findVMLinux scans multiple well-known paths for vmlinux kernel images.
|
||||
func findVMLinux() (*internal.SafeELFFile, error) {
|
||||
release, err := internal.KernelRelease()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// use same list of locations as libbpf
|
||||
// https://github.com/libbpf/libbpf/blob/9a3a42608dbe3731256a5682a125ac1e23bced8f/src/btf.c#L3114-L3122
|
||||
locations := []string{
|
||||
"/boot/vmlinux-%s",
|
||||
"/lib/modules/%s/vmlinux-%[1]s",
|
||||
"/lib/modules/%s/build/vmlinux",
|
||||
"/usr/lib/modules/%s/kernel/vmlinux",
|
||||
"/usr/lib/debug/boot/vmlinux-%s",
|
||||
"/usr/lib/debug/boot/vmlinux-%s.debug",
|
||||
"/usr/lib/debug/lib/modules/%s/vmlinux",
|
||||
}
|
||||
|
||||
for _, loc := range locations {
|
||||
file, err := internal.OpenSafeELFFile(fmt.Sprintf(loc, release))
|
||||
if errors.Is(err, os.ErrNotExist) {
|
||||
continue
|
||||
}
|
||||
return file, err
|
||||
}
|
||||
|
||||
return nil, fmt.Errorf("no BTF found for kernel version %s: %w", release, internal.ErrNotSupported)
|
||||
}
|
||||
|
||||
// parseBTFHeader parses the header of the .BTF section.
|
||||
func parseBTFHeader(r io.Reader, bo binary.ByteOrder) (*btfHeader, error) {
|
||||
var header btfHeader
|
||||
if err := binary.Read(r, bo, &header); err != nil {
|
||||
return nil, fmt.Errorf("can't read header: %v", err)
|
||||
}
|
||||
|
||||
if header.Magic != btfMagic {
|
||||
return nil, fmt.Errorf("incorrect magic value %v", header.Magic)
|
||||
}
|
||||
|
||||
if header.Version != 1 {
|
||||
return nil, fmt.Errorf("unexpected version %v", header.Version)
|
||||
}
|
||||
|
||||
if header.Flags != 0 {
|
||||
return nil, fmt.Errorf("unsupported flags %v", header.Flags)
|
||||
}
|
||||
|
||||
remainder := int64(header.HdrLen) - int64(binary.Size(&header))
|
||||
if remainder < 0 {
|
||||
return nil, errors.New("header length shorter than btfHeader size")
|
||||
}
|
||||
|
||||
if _, err := io.CopyN(internal.DiscardZeroes{}, r, remainder); err != nil {
|
||||
return nil, fmt.Errorf("header padding: %v", err)
|
||||
}
|
||||
|
||||
return &header, nil
|
||||
}
|
||||
|
||||
func guessRawBTFByteOrder(r io.ReaderAt) binary.ByteOrder {
|
||||
buf := new(bufio.Reader)
|
||||
for _, bo := range []binary.ByteOrder{
|
||||
binary.LittleEndian,
|
||||
binary.BigEndian,
|
||||
} {
|
||||
buf.Reset(io.NewSectionReader(r, 0, math.MaxInt64))
|
||||
if _, err := parseBTFHeader(buf, bo); err == nil {
|
||||
return bo
|
||||
}
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// parseBTF reads a .BTF section into memory and parses it into a list of
|
||||
// raw types and a string table.
|
||||
func parseBTF(btf io.ReaderAt, bo binary.ByteOrder, baseStrings *stringTable) ([]rawType, *stringTable, error) {
|
||||
buf := internal.NewBufferedSectionReader(btf, 0, math.MaxInt64)
|
||||
header, err := parseBTFHeader(buf, bo)
|
||||
if err != nil {
|
||||
return nil, nil, fmt.Errorf("parsing .BTF header: %v", err)
|
||||
}
|
||||
|
||||
rawStrings, err := readStringTable(io.NewSectionReader(btf, header.stringStart(), int64(header.StringLen)),
|
||||
baseStrings)
|
||||
if err != nil {
|
||||
return nil, nil, fmt.Errorf("can't read type names: %w", err)
|
||||
}
|
||||
|
||||
buf.Reset(io.NewSectionReader(btf, header.typeStart(), int64(header.TypeLen)))
|
||||
rawTypes, err := readTypes(buf, bo, header.TypeLen)
|
||||
if err != nil {
|
||||
return nil, nil, fmt.Errorf("can't read types: %w", err)
|
||||
}
|
||||
|
||||
return rawTypes, rawStrings, nil
|
||||
}
|
||||
|
||||
type variable struct {
|
||||
section string
|
||||
name string
|
||||
}
|
||||
|
||||
func fixupDatasec(rawTypes []rawType, rawStrings *stringTable, sectionSizes map[string]uint32, variableOffsets map[variable]uint32) error {
|
||||
for i, rawType := range rawTypes {
|
||||
if rawType.Kind() != kindDatasec {
|
||||
continue
|
||||
}
|
||||
|
||||
name, err := rawStrings.Lookup(rawType.NameOff)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
if name == ".kconfig" || name == ".ksyms" {
|
||||
return fmt.Errorf("reference to %s: %w", name, ErrNotSupported)
|
||||
}
|
||||
|
||||
if rawTypes[i].SizeType != 0 {
|
||||
continue
|
||||
}
|
||||
|
||||
size, ok := sectionSizes[name]
|
||||
if !ok {
|
||||
return fmt.Errorf("data section %s: missing size", name)
|
||||
}
|
||||
|
||||
rawTypes[i].SizeType = size
|
||||
|
||||
secinfos := rawType.data.([]btfVarSecinfo)
|
||||
for j, secInfo := range secinfos {
|
||||
id := int(secInfo.Type - 1)
|
||||
if id >= len(rawTypes) {
|
||||
return fmt.Errorf("data section %s: invalid type id %d for variable %d", name, id, j)
|
||||
}
|
||||
|
||||
varName, err := rawStrings.Lookup(rawTypes[id].NameOff)
|
||||
if err != nil {
|
||||
return fmt.Errorf("data section %s: can't get name for type %d: %w", name, id, err)
|
||||
}
|
||||
|
||||
offset, ok := variableOffsets[variable{name, varName}]
|
||||
if !ok {
|
||||
return fmt.Errorf("data section %s: missing offset for variable %s", name, varName)
|
||||
}
|
||||
|
||||
secinfos[j].Offset = offset
|
||||
}
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// Copy creates a copy of Spec.
|
||||
func (s *Spec) Copy() *Spec {
|
||||
types := copyTypes(s.types, nil)
|
||||
|
||||
typeIDOffset := TypeID(0)
|
||||
if len(s.types) != 0 {
|
||||
typeIDOffset = s.typeIDs[s.types[0]]
|
||||
}
|
||||
typeIDs, typesByName := indexTypes(types, typeIDOffset)
|
||||
|
||||
// NB: Other parts of spec are not copied since they are immutable.
|
||||
return &Spec{
|
||||
s.rawTypes,
|
||||
s.strings,
|
||||
types,
|
||||
typeIDs,
|
||||
typesByName,
|
||||
s.byteOrder,
|
||||
}
|
||||
}
|
||||
|
||||
type marshalOpts struct {
|
||||
ByteOrder binary.ByteOrder
|
||||
StripFuncLinkage bool
|
||||
}
|
||||
|
||||
func (s *Spec) marshal(opts marshalOpts) ([]byte, error) {
|
||||
var (
|
||||
buf bytes.Buffer
|
||||
header = new(btfHeader)
|
||||
headerLen = binary.Size(header)
|
||||
)
|
||||
|
||||
// Reserve space for the header. We have to write it last since
|
||||
// we don't know the size of the type section yet.
|
||||
_, _ = buf.Write(make([]byte, headerLen))
|
||||
|
||||
// Write type section, just after the header.
|
||||
for _, raw := range s.rawTypes {
|
||||
switch {
|
||||
case opts.StripFuncLinkage && raw.Kind() == kindFunc:
|
||||
raw.SetLinkage(StaticFunc)
|
||||
}
|
||||
|
||||
if err := raw.Marshal(&buf, opts.ByteOrder); err != nil {
|
||||
return nil, fmt.Errorf("can't marshal BTF: %w", err)
|
||||
}
|
||||
}
|
||||
|
||||
typeLen := uint32(buf.Len() - headerLen)
|
||||
|
||||
// Write string section after type section.
|
||||
stringsLen := s.strings.Length()
|
||||
buf.Grow(stringsLen)
|
||||
if err := s.strings.Marshal(&buf); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// Fill out the header, and write it out.
|
||||
header = &btfHeader{
|
||||
Magic: btfMagic,
|
||||
Version: 1,
|
||||
Flags: 0,
|
||||
HdrLen: uint32(headerLen),
|
||||
TypeOff: 0,
|
||||
TypeLen: typeLen,
|
||||
StringOff: typeLen,
|
||||
StringLen: uint32(stringsLen),
|
||||
}
|
||||
|
||||
raw := buf.Bytes()
|
||||
err := binary.Write(sliceWriter(raw[:headerLen]), opts.ByteOrder, header)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("can't write header: %v", err)
|
||||
}
|
||||
|
||||
return raw, nil
|
||||
}
|
||||
|
||||
type sliceWriter []byte
|
||||
|
||||
func (sw sliceWriter) Write(p []byte) (int, error) {
|
||||
if len(p) != len(sw) {
|
||||
return 0, errors.New("size doesn't match")
|
||||
}
|
||||
|
||||
return copy(sw, p), nil
|
||||
}
|
||||
|
||||
// TypeByID returns the BTF Type with the given type ID.
|
||||
//
|
||||
// Returns an error wrapping ErrNotFound if a Type with the given ID
|
||||
// does not exist in the Spec.
|
||||
func (s *Spec) TypeByID(id TypeID) (Type, error) {
|
||||
return s.types.ByID(id)
|
||||
}
|
||||
|
||||
// TypeID returns the ID for a given Type.
|
||||
//
|
||||
// Returns an error wrapping ErrNoFound if the type isn't part of the Spec.
|
||||
func (s *Spec) TypeID(typ Type) (TypeID, error) {
|
||||
if _, ok := typ.(*Void); ok {
|
||||
// Equality is weird for void, since it is a zero sized type.
|
||||
return 0, nil
|
||||
}
|
||||
|
||||
id, ok := s.typeIDs[typ]
|
||||
if !ok {
|
||||
return 0, fmt.Errorf("no ID for type %s: %w", typ, ErrNotFound)
|
||||
}
|
||||
|
||||
return id, nil
|
||||
}
|
||||
|
||||
// AnyTypesByName returns a list of BTF Types with the given name.
|
||||
//
|
||||
// If the BTF blob describes multiple compilation units like vmlinux, multiple
|
||||
// Types with the same name and kind can exist, but might not describe the same
|
||||
// data structure.
|
||||
//
|
||||
// Returns an error wrapping ErrNotFound if no matching Type exists in the Spec.
|
||||
func (s *Spec) AnyTypesByName(name string) ([]Type, error) {
|
||||
types := s.namedTypes[newEssentialName(name)]
|
||||
if len(types) == 0 {
|
||||
return nil, fmt.Errorf("type name %s: %w", name, ErrNotFound)
|
||||
}
|
||||
|
||||
// Return a copy to prevent changes to namedTypes.
|
||||
result := make([]Type, 0, len(types))
|
||||
for _, t := range types {
|
||||
// Match against the full name, not just the essential one
|
||||
// in case the type being looked up is a struct flavor.
|
||||
if t.TypeName() == name {
|
||||
result = append(result, t)
|
||||
}
|
||||
}
|
||||
return result, nil
|
||||
}
|
||||
|
||||
// AnyTypeByName returns a Type with the given name.
|
||||
//
|
||||
// Returns an error if multiple types of that name exist.
|
||||
func (s *Spec) AnyTypeByName(name string) (Type, error) {
|
||||
types, err := s.AnyTypesByName(name)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
if len(types) > 1 {
|
||||
return nil, fmt.Errorf("found multiple types: %v", types)
|
||||
}
|
||||
|
||||
return types[0], nil
|
||||
}
|
||||
|
||||
// TypeByName searches for a Type with a specific name. Since multiple
|
||||
// Types with the same name can exist, the parameter typ is taken to
|
||||
// narrow down the search in case of a clash.
|
||||
//
|
||||
// typ must be a non-nil pointer to an implementation of a Type.
|
||||
// On success, the address of the found Type will be copied to typ.
|
||||
//
|
||||
// Returns an error wrapping ErrNotFound if no matching
|
||||
// Type exists in the Spec. If multiple candidates are found,
|
||||
// an error is returned.
|
||||
func (s *Spec) TypeByName(name string, typ interface{}) error {
|
||||
typValue := reflect.ValueOf(typ)
|
||||
if typValue.Kind() != reflect.Ptr {
|
||||
return fmt.Errorf("%T is not a pointer", typ)
|
||||
}
|
||||
|
||||
typPtr := typValue.Elem()
|
||||
if !typPtr.CanSet() {
|
||||
return fmt.Errorf("%T cannot be set", typ)
|
||||
}
|
||||
|
||||
wanted := typPtr.Type()
|
||||
if !wanted.AssignableTo(reflect.TypeOf((*Type)(nil)).Elem()) {
|
||||
return fmt.Errorf("%T does not satisfy Type interface", typ)
|
||||
}
|
||||
|
||||
types, err := s.AnyTypesByName(name)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
var candidate Type
|
||||
for _, typ := range types {
|
||||
if reflect.TypeOf(typ) != wanted {
|
||||
continue
|
||||
}
|
||||
|
||||
if candidate != nil {
|
||||
return fmt.Errorf("type %s: multiple candidates for %T", name, typ)
|
||||
}
|
||||
|
||||
candidate = typ
|
||||
}
|
||||
|
||||
if candidate == nil {
|
||||
return fmt.Errorf("type %s: %w", name, ErrNotFound)
|
||||
}
|
||||
|
||||
typPtr.Set(reflect.ValueOf(candidate))
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// LoadSplitSpecFromReader loads split BTF from a reader.
|
||||
//
|
||||
// Types from base are used to resolve references in the split BTF.
|
||||
// The returned Spec only contains types from the split BTF, not from the base.
|
||||
func LoadSplitSpecFromReader(r io.ReaderAt, base *Spec) (*Spec, error) {
|
||||
return loadRawSpec(r, internal.NativeEndian, base.types, base.strings)
|
||||
}
|
||||
|
||||
// TypesIterator iterates over types of a given spec.
|
||||
type TypesIterator struct {
|
||||
spec *Spec
|
||||
index int
|
||||
// The last visited type in the spec.
|
||||
Type Type
|
||||
}
|
||||
|
||||
// Iterate returns the types iterator.
|
||||
func (s *Spec) Iterate() *TypesIterator {
|
||||
return &TypesIterator{spec: s, index: 0}
|
||||
}
|
||||
|
||||
// Next returns true as long as there are any remaining types.
|
||||
func (iter *TypesIterator) Next() bool {
|
||||
if len(iter.spec.types) <= iter.index {
|
||||
return false
|
||||
}
|
||||
|
||||
iter.Type = iter.spec.types[iter.index]
|
||||
iter.index++
|
||||
return true
|
||||
}
|
||||
|
||||
// Handle is a reference to BTF loaded into the kernel.
|
||||
type Handle struct {
|
||||
fd *sys.FD
|
||||
|
||||
// Size of the raw BTF in bytes.
|
||||
size uint32
|
||||
}
|
||||
|
||||
// NewHandle loads BTF into the kernel.
|
||||
//
|
||||
// Returns ErrNotSupported if BTF is not supported.
|
||||
func NewHandle(spec *Spec) (*Handle, error) {
|
||||
if err := haveBTF(); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
if spec.byteOrder != internal.NativeEndian {
|
||||
return nil, fmt.Errorf("can't load %s BTF on %s", spec.byteOrder, internal.NativeEndian)
|
||||
}
|
||||
|
||||
btf, err := spec.marshal(marshalOpts{
|
||||
ByteOrder: internal.NativeEndian,
|
||||
StripFuncLinkage: haveFuncLinkage() != nil,
|
||||
})
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("can't marshal BTF: %w", err)
|
||||
}
|
||||
|
||||
if uint64(len(btf)) > math.MaxUint32 {
|
||||
return nil, errors.New("BTF exceeds the maximum size")
|
||||
}
|
||||
|
||||
attr := &sys.BtfLoadAttr{
|
||||
Btf: sys.NewSlicePointer(btf),
|
||||
BtfSize: uint32(len(btf)),
|
||||
}
|
||||
|
||||
fd, err := sys.BtfLoad(attr)
|
||||
if err != nil {
|
||||
logBuf := make([]byte, 64*1024)
|
||||
attr.BtfLogBuf = sys.NewSlicePointer(logBuf)
|
||||
attr.BtfLogSize = uint32(len(logBuf))
|
||||
attr.BtfLogLevel = 1
|
||||
// NB: The syscall will never return ENOSPC as of 5.18-rc4.
|
||||
_, _ = sys.BtfLoad(attr)
|
||||
return nil, internal.ErrorWithLog(err, logBuf)
|
||||
}
|
||||
|
||||
return &Handle{fd, attr.BtfSize}, nil
|
||||
}
|
||||
|
||||
// NewHandleFromID returns the BTF handle for a given id.
|
||||
//
|
||||
// Prefer calling [ebpf.Program.Handle] or [ebpf.Map.Handle] if possible.
|
||||
//
|
||||
// Returns ErrNotExist, if there is no BTF with the given id.
|
||||
//
|
||||
// Requires CAP_SYS_ADMIN.
|
||||
func NewHandleFromID(id ID) (*Handle, error) {
|
||||
fd, err := sys.BtfGetFdById(&sys.BtfGetFdByIdAttr{
|
||||
Id: uint32(id),
|
||||
})
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("get FD for ID %d: %w", id, err)
|
||||
}
|
||||
|
||||
info, err := newHandleInfoFromFD(fd)
|
||||
if err != nil {
|
||||
_ = fd.Close()
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return &Handle{fd, info.size}, nil
|
||||
}
|
||||
|
||||
// Spec parses the kernel BTF into Go types.
|
||||
//
|
||||
// base is used to decode split BTF and may be nil.
|
||||
func (h *Handle) Spec(base *Spec) (*Spec, error) {
|
||||
var btfInfo sys.BtfInfo
|
||||
btfBuffer := make([]byte, h.size)
|
||||
btfInfo.Btf, btfInfo.BtfSize = sys.NewSlicePointerLen(btfBuffer)
|
||||
|
||||
if err := sys.ObjInfo(h.fd, &btfInfo); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
var baseTypes types
|
||||
var baseStrings *stringTable
|
||||
if base != nil {
|
||||
baseTypes = base.types
|
||||
baseStrings = base.strings
|
||||
}
|
||||
|
||||
return loadRawSpec(bytes.NewReader(btfBuffer), internal.NativeEndian, baseTypes, baseStrings)
|
||||
}
|
||||
|
||||
// Close destroys the handle.
|
||||
//
|
||||
// Subsequent calls to FD will return an invalid value.
|
||||
func (h *Handle) Close() error {
|
||||
if h == nil {
|
||||
return nil
|
||||
}
|
||||
|
||||
return h.fd.Close()
|
||||
}
|
||||
|
||||
// FD returns the file descriptor for the handle.
|
||||
func (h *Handle) FD() int {
|
||||
return h.fd.Int()
|
||||
}
|
||||
|
||||
// Info returns metadata about the handle.
|
||||
func (h *Handle) Info() (*HandleInfo, error) {
|
||||
return newHandleInfoFromFD(h.fd)
|
||||
}
|
||||
|
||||
func marshalBTF(types interface{}, strings []byte, bo binary.ByteOrder) []byte {
|
||||
const minHeaderLength = 24
|
||||
|
||||
typesLen := uint32(binary.Size(types))
|
||||
header := btfHeader{
|
||||
Magic: btfMagic,
|
||||
Version: 1,
|
||||
HdrLen: minHeaderLength,
|
||||
TypeOff: 0,
|
||||
TypeLen: typesLen,
|
||||
StringOff: typesLen,
|
||||
StringLen: uint32(len(strings)),
|
||||
}
|
||||
|
||||
buf := new(bytes.Buffer)
|
||||
_ = binary.Write(buf, bo, &header)
|
||||
_ = binary.Write(buf, bo, types)
|
||||
buf.Write(strings)
|
||||
|
||||
return buf.Bytes()
|
||||
}
|
||||
|
||||
var haveBTF = internal.FeatureTest("BTF", "5.1", func() error {
|
||||
var (
|
||||
types struct {
|
||||
Integer btfType
|
||||
Var btfType
|
||||
btfVar struct{ Linkage uint32 }
|
||||
}
|
||||
strings = []byte{0, 'a', 0}
|
||||
)
|
||||
|
||||
// We use a BTF_KIND_VAR here, to make sure that
|
||||
// the kernel understands BTF at least as well as we
|
||||
// do. BTF_KIND_VAR was introduced ~5.1.
|
||||
types.Integer.SetKind(kindPointer)
|
||||
types.Var.NameOff = 1
|
||||
types.Var.SetKind(kindVar)
|
||||
types.Var.SizeType = 1
|
||||
|
||||
btf := marshalBTF(&types, strings, internal.NativeEndian)
|
||||
|
||||
fd, err := sys.BtfLoad(&sys.BtfLoadAttr{
|
||||
Btf: sys.NewSlicePointer(btf),
|
||||
BtfSize: uint32(len(btf)),
|
||||
})
|
||||
if errors.Is(err, unix.EINVAL) || errors.Is(err, unix.EPERM) {
|
||||
// Treat both EINVAL and EPERM as not supported: loading the program
|
||||
// might still succeed without BTF.
|
||||
return internal.ErrNotSupported
|
||||
}
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
fd.Close()
|
||||
return nil
|
||||
})
|
||||
|
||||
var haveFuncLinkage = internal.FeatureTest("BTF func linkage", "5.6", func() error {
|
||||
if err := haveBTF(); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
var (
|
||||
types struct {
|
||||
FuncProto btfType
|
||||
Func btfType
|
||||
}
|
||||
strings = []byte{0, 'a', 0}
|
||||
)
|
||||
|
||||
types.FuncProto.SetKind(kindFuncProto)
|
||||
types.Func.SetKind(kindFunc)
|
||||
types.Func.SizeType = 1 // aka FuncProto
|
||||
types.Func.NameOff = 1
|
||||
types.Func.SetLinkage(GlobalFunc)
|
||||
|
||||
btf := marshalBTF(&types, strings, internal.NativeEndian)
|
||||
|
||||
fd, err := sys.BtfLoad(&sys.BtfLoadAttr{
|
||||
Btf: sys.NewSlicePointer(btf),
|
||||
BtfSize: uint32(len(btf)),
|
||||
})
|
||||
if errors.Is(err, unix.EINVAL) {
|
||||
return internal.ErrNotSupported
|
||||
}
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
fd.Close()
|
||||
return nil
|
||||
})
|
|
@ -6,6 +6,8 @@ import (
|
|||
"io"
|
||||
)
|
||||
|
||||
//go:generate stringer -linecomment -output=btf_types_string.go -type=FuncLinkage,VarLinkage
|
||||
|
||||
// btfKind describes a Type.
|
||||
type btfKind uint8
|
||||
|
||||
|
@ -29,19 +31,32 @@ const (
|
|||
// Added ~5.1
|
||||
kindVar
|
||||
kindDatasec
|
||||
// Added ~5.13
|
||||
kindFloat
|
||||
)
|
||||
|
||||
type btfFuncLinkage uint8
|
||||
// FuncLinkage describes BTF function linkage metadata.
|
||||
type FuncLinkage int
|
||||
|
||||
// Equivalent of enum btf_func_linkage.
|
||||
const (
|
||||
StaticFunc FuncLinkage = iota // static
|
||||
GlobalFunc // global
|
||||
ExternFunc // extern
|
||||
)
|
||||
|
||||
// VarLinkage describes BTF variable linkage metadata.
|
||||
type VarLinkage int
|
||||
|
||||
const (
|
||||
linkageStatic btfFuncLinkage = iota
|
||||
linkageGlobal
|
||||
linkageExtern
|
||||
StaticVar VarLinkage = iota // static
|
||||
GlobalVar // global
|
||||
ExternVar // extern
|
||||
)
|
||||
|
||||
const (
|
||||
btfTypeKindShift = 24
|
||||
btfTypeKindLen = 4
|
||||
btfTypeKindLen = 5
|
||||
btfTypeVlenShift = 0
|
||||
btfTypeVlenMask = 16
|
||||
btfTypeKindFlagShift = 31
|
||||
|
@ -54,8 +69,8 @@ type btfType struct {
|
|||
/* "info" bits arrangement
|
||||
* bits 0-15: vlen (e.g. # of struct's members), linkage
|
||||
* bits 16-23: unused
|
||||
* bits 24-27: kind (e.g. int, ptr, array...etc)
|
||||
* bits 28-30: unused
|
||||
* bits 24-28: kind (e.g. int, ptr, array...etc)
|
||||
* bits 29-30: unused
|
||||
* bit 31: kind_flag, currently used by
|
||||
* struct, union and fwd
|
||||
*/
|
||||
|
@ -104,6 +119,8 @@ func (k btfKind) String() string {
|
|||
return "Variable"
|
||||
case kindDatasec:
|
||||
return "Section"
|
||||
case kindFloat:
|
||||
return "Float"
|
||||
default:
|
||||
return fmt.Sprintf("Unknown (%d)", k)
|
||||
}
|
||||
|
@ -113,13 +130,22 @@ func mask(len uint32) uint32 {
|
|||
return (1 << len) - 1
|
||||
}
|
||||
|
||||
func readBits(value, len, shift uint32) uint32 {
|
||||
return (value >> shift) & mask(len)
|
||||
}
|
||||
|
||||
func writeBits(value, len, shift, new uint32) uint32 {
|
||||
value &^= mask(len) << shift
|
||||
value |= (new & mask(len)) << shift
|
||||
return value
|
||||
}
|
||||
|
||||
func (bt *btfType) info(len, shift uint32) uint32 {
|
||||
return (bt.Info >> shift) & mask(len)
|
||||
return readBits(bt.Info, len, shift)
|
||||
}
|
||||
|
||||
func (bt *btfType) setInfo(value, len, shift uint32) {
|
||||
bt.Info &^= mask(len) << shift
|
||||
bt.Info |= (value & mask(len)) << shift
|
||||
bt.Info = writeBits(bt.Info, len, shift, value)
|
||||
}
|
||||
|
||||
func (bt *btfType) Kind() btfKind {
|
||||
|
@ -142,11 +168,11 @@ func (bt *btfType) KindFlag() bool {
|
|||
return bt.info(btfTypeKindFlagMask, btfTypeKindFlagShift) == 1
|
||||
}
|
||||
|
||||
func (bt *btfType) Linkage() btfFuncLinkage {
|
||||
return btfFuncLinkage(bt.info(btfTypeVlenMask, btfTypeVlenShift))
|
||||
func (bt *btfType) Linkage() FuncLinkage {
|
||||
return FuncLinkage(bt.info(btfTypeVlenMask, btfTypeVlenShift))
|
||||
}
|
||||
|
||||
func (bt *btfType) SetLinkage(linkage btfFuncLinkage) {
|
||||
func (bt *btfType) SetLinkage(linkage FuncLinkage) {
|
||||
bt.setInfo(uint32(linkage), btfTypeVlenMask, btfTypeVlenShift)
|
||||
}
|
||||
|
||||
|
@ -160,6 +186,10 @@ func (bt *btfType) Size() uint32 {
|
|||
return bt.SizeType
|
||||
}
|
||||
|
||||
func (bt *btfType) SetSize(size uint32) {
|
||||
bt.SizeType = size
|
||||
}
|
||||
|
||||
type rawType struct {
|
||||
btfType
|
||||
data interface{}
|
||||
|
@ -177,6 +207,50 @@ func (rt *rawType) Marshal(w io.Writer, bo binary.ByteOrder) error {
|
|||
return binary.Write(w, bo, rt.data)
|
||||
}
|
||||
|
||||
// btfInt encodes additional data for integers.
|
||||
//
|
||||
// ? ? ? ? e e e e o o o o o o o o ? ? ? ? ? ? ? ? b b b b b b b b
|
||||
// ? = undefined
|
||||
// e = encoding
|
||||
// o = offset (bitfields?)
|
||||
// b = bits (bitfields)
|
||||
type btfInt struct {
|
||||
Raw uint32
|
||||
}
|
||||
|
||||
const (
|
||||
btfIntEncodingLen = 4
|
||||
btfIntEncodingShift = 24
|
||||
btfIntOffsetLen = 8
|
||||
btfIntOffsetShift = 16
|
||||
btfIntBitsLen = 8
|
||||
btfIntBitsShift = 0
|
||||
)
|
||||
|
||||
func (bi btfInt) Encoding() IntEncoding {
|
||||
return IntEncoding(readBits(bi.Raw, btfIntEncodingLen, btfIntEncodingShift))
|
||||
}
|
||||
|
||||
func (bi *btfInt) SetEncoding(e IntEncoding) {
|
||||
bi.Raw = writeBits(uint32(bi.Raw), btfIntEncodingLen, btfIntEncodingShift, uint32(e))
|
||||
}
|
||||
|
||||
func (bi btfInt) Offset() Bits {
|
||||
return Bits(readBits(bi.Raw, btfIntOffsetLen, btfIntOffsetShift))
|
||||
}
|
||||
|
||||
func (bi *btfInt) SetOffset(offset uint32) {
|
||||
bi.Raw = writeBits(bi.Raw, btfIntOffsetLen, btfIntOffsetShift, offset)
|
||||
}
|
||||
|
||||
func (bi btfInt) Bits() Bits {
|
||||
return Bits(readBits(bi.Raw, btfIntBitsLen, btfIntBitsShift))
|
||||
}
|
||||
|
||||
func (bi *btfInt) SetBits(bits byte) {
|
||||
bi.Raw = writeBits(bi.Raw, btfIntBitsLen, btfIntBitsShift, uint32(bits))
|
||||
}
|
||||
|
||||
type btfArray struct {
|
||||
Type TypeID
|
||||
IndexType TypeID
|
||||
|
@ -209,11 +283,14 @@ type btfParam struct {
|
|||
Type TypeID
|
||||
}
|
||||
|
||||
func readTypes(r io.Reader, bo binary.ByteOrder) ([]rawType, error) {
|
||||
var (
|
||||
header btfType
|
||||
types []rawType
|
||||
)
|
||||
func readTypes(r io.Reader, bo binary.ByteOrder, typeLen uint32) ([]rawType, error) {
|
||||
var header btfType
|
||||
// because of the interleaving between types and struct members it is difficult to
|
||||
// precompute the numbers of raw types this will parse
|
||||
// this "guess" is a good first estimation
|
||||
sizeOfbtfType := uintptr(binary.Size(btfType{}))
|
||||
tyMaxCount := uintptr(typeLen) / sizeOfbtfType / 2
|
||||
types := make([]rawType, 0, tyMaxCount)
|
||||
|
||||
for id := TypeID(1); ; id++ {
|
||||
if err := binary.Read(r, bo, &header); err == io.EOF {
|
||||
|
@ -225,7 +302,7 @@ func readTypes(r io.Reader, bo binary.ByteOrder) ([]rawType, error) {
|
|||
var data interface{}
|
||||
switch header.Kind() {
|
||||
case kindInt:
|
||||
data = new(uint32)
|
||||
data = new(btfInt)
|
||||
case kindPointer:
|
||||
case kindArray:
|
||||
data = new(btfArray)
|
||||
|
@ -247,6 +324,7 @@ func readTypes(r io.Reader, bo binary.ByteOrder) ([]rawType, error) {
|
|||
data = new(btfVariable)
|
||||
case kindDatasec:
|
||||
data = make([]btfVarSecinfo, header.Vlen())
|
||||
case kindFloat:
|
||||
default:
|
||||
return nil, fmt.Errorf("type id %v: unknown kind: %v", id, header.Kind())
|
||||
}
|
||||
|
@ -263,7 +341,3 @@ func readTypes(r io.Reader, bo binary.ByteOrder) ([]rawType, error) {
|
|||
types = append(types, rawType{header, data})
|
||||
}
|
||||
}
|
||||
|
||||
func intEncoding(raw uint32) (IntEncoding, uint32, byte) {
|
||||
return IntEncoding((raw & 0x0f000000) >> 24), (raw & 0x00ff0000) >> 16, byte(raw & 0x000000ff)
|
||||
}
|
|
@ -0,0 +1,44 @@
|
|||
// Code generated by "stringer -linecomment -output=btf_types_string.go -type=FuncLinkage,VarLinkage"; DO NOT EDIT.
|
||||
|
||||
package btf
|
||||
|
||||
import "strconv"
|
||||
|
||||
func _() {
|
||||
// An "invalid array index" compiler error signifies that the constant values have changed.
|
||||
// Re-run the stringer command to generate them again.
|
||||
var x [1]struct{}
|
||||
_ = x[StaticFunc-0]
|
||||
_ = x[GlobalFunc-1]
|
||||
_ = x[ExternFunc-2]
|
||||
}
|
||||
|
||||
const _FuncLinkage_name = "staticglobalextern"
|
||||
|
||||
var _FuncLinkage_index = [...]uint8{0, 6, 12, 18}
|
||||
|
||||
func (i FuncLinkage) String() string {
|
||||
if i < 0 || i >= FuncLinkage(len(_FuncLinkage_index)-1) {
|
||||
return "FuncLinkage(" + strconv.FormatInt(int64(i), 10) + ")"
|
||||
}
|
||||
return _FuncLinkage_name[_FuncLinkage_index[i]:_FuncLinkage_index[i+1]]
|
||||
}
|
||||
func _() {
|
||||
// An "invalid array index" compiler error signifies that the constant values have changed.
|
||||
// Re-run the stringer command to generate them again.
|
||||
var x [1]struct{}
|
||||
_ = x[StaticVar-0]
|
||||
_ = x[GlobalVar-1]
|
||||
_ = x[ExternVar-2]
|
||||
}
|
||||
|
||||
const _VarLinkage_name = "staticglobalextern"
|
||||
|
||||
var _VarLinkage_index = [...]uint8{0, 6, 12, 18}
|
||||
|
||||
func (i VarLinkage) String() string {
|
||||
if i < 0 || i >= VarLinkage(len(_VarLinkage_index)-1) {
|
||||
return "VarLinkage(" + strconv.FormatInt(int64(i), 10) + ")"
|
||||
}
|
||||
return _VarLinkage_name[_VarLinkage_index[i]:_VarLinkage_index[i+1]]
|
||||
}
|
|
@ -0,0 +1,972 @@
|
|||
package btf
|
||||
|
||||
import (
|
||||
"encoding/binary"
|
||||
"errors"
|
||||
"fmt"
|
||||
"math"
|
||||
"reflect"
|
||||
"strconv"
|
||||
"strings"
|
||||
|
||||
"github.com/cilium/ebpf/asm"
|
||||
)
|
||||
|
||||
// Code in this file is derived from libbpf, which is available under a BSD
|
||||
// 2-Clause license.
|
||||
|
||||
// COREFixup is the result of computing a CO-RE relocation for a target.
|
||||
type COREFixup struct {
|
||||
kind coreKind
|
||||
local uint32
|
||||
target uint32
|
||||
// True if there is no valid fixup. The instruction is replaced with an
|
||||
// invalid dummy.
|
||||
poison bool
|
||||
// True if the validation of the local value should be skipped. Used by
|
||||
// some kinds of bitfield relocations.
|
||||
skipLocalValidation bool
|
||||
}
|
||||
|
||||
func (f *COREFixup) equal(other COREFixup) bool {
|
||||
return f.local == other.local && f.target == other.target
|
||||
}
|
||||
|
||||
func (f *COREFixup) String() string {
|
||||
if f.poison {
|
||||
return fmt.Sprintf("%s=poison", f.kind)
|
||||
}
|
||||
return fmt.Sprintf("%s=%d->%d", f.kind, f.local, f.target)
|
||||
}
|
||||
|
||||
func (f *COREFixup) Apply(ins *asm.Instruction) error {
|
||||
if f.poison {
|
||||
const badRelo = 0xbad2310
|
||||
|
||||
*ins = asm.BuiltinFunc(badRelo).Call()
|
||||
return nil
|
||||
}
|
||||
|
||||
switch class := ins.OpCode.Class(); class {
|
||||
case asm.LdXClass, asm.StClass, asm.StXClass:
|
||||
if want := int16(f.local); !f.skipLocalValidation && want != ins.Offset {
|
||||
return fmt.Errorf("invalid offset %d, expected %d", ins.Offset, f.local)
|
||||
}
|
||||
|
||||
if f.target > math.MaxInt16 {
|
||||
return fmt.Errorf("offset %d exceeds MaxInt16", f.target)
|
||||
}
|
||||
|
||||
ins.Offset = int16(f.target)
|
||||
|
||||
case asm.LdClass:
|
||||
if !ins.IsConstantLoad(asm.DWord) {
|
||||
return fmt.Errorf("not a dword-sized immediate load")
|
||||
}
|
||||
|
||||
if want := int64(f.local); !f.skipLocalValidation && want != ins.Constant {
|
||||
return fmt.Errorf("invalid immediate %d, expected %d (fixup: %v)", ins.Constant, want, f)
|
||||
}
|
||||
|
||||
ins.Constant = int64(f.target)
|
||||
|
||||
case asm.ALUClass:
|
||||
if ins.OpCode.ALUOp() == asm.Swap {
|
||||
return fmt.Errorf("relocation against swap")
|
||||
}
|
||||
|
||||
fallthrough
|
||||
|
||||
case asm.ALU64Class:
|
||||
if src := ins.OpCode.Source(); src != asm.ImmSource {
|
||||
return fmt.Errorf("invalid source %s", src)
|
||||
}
|
||||
|
||||
if want := int64(f.local); !f.skipLocalValidation && want != ins.Constant {
|
||||
return fmt.Errorf("invalid immediate %d, expected %d (fixup: %v, kind: %v, ins: %v)", ins.Constant, want, f, f.kind, ins)
|
||||
}
|
||||
|
||||
if f.target > math.MaxInt32 {
|
||||
return fmt.Errorf("immediate %d exceeds MaxInt32", f.target)
|
||||
}
|
||||
|
||||
ins.Constant = int64(f.target)
|
||||
|
||||
default:
|
||||
return fmt.Errorf("invalid class %s", class)
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
func (f COREFixup) isNonExistant() bool {
|
||||
return f.kind.checksForExistence() && f.target == 0
|
||||
}
|
||||
|
||||
// coreKind is the type of CO-RE relocation as specified in BPF source code.
|
||||
type coreKind uint32
|
||||
|
||||
const (
|
||||
reloFieldByteOffset coreKind = iota /* field byte offset */
|
||||
reloFieldByteSize /* field size in bytes */
|
||||
reloFieldExists /* field existence in target kernel */
|
||||
reloFieldSigned /* field signedness (0 - unsigned, 1 - signed) */
|
||||
reloFieldLShiftU64 /* bitfield-specific left bitshift */
|
||||
reloFieldRShiftU64 /* bitfield-specific right bitshift */
|
||||
reloTypeIDLocal /* type ID in local BPF object */
|
||||
reloTypeIDTarget /* type ID in target kernel */
|
||||
reloTypeExists /* type existence in target kernel */
|
||||
reloTypeSize /* type size in bytes */
|
||||
reloEnumvalExists /* enum value existence in target kernel */
|
||||
reloEnumvalValue /* enum value integer value */
|
||||
)
|
||||
|
||||
func (k coreKind) checksForExistence() bool {
|
||||
return k == reloEnumvalExists || k == reloTypeExists || k == reloFieldExists
|
||||
}
|
||||
|
||||
func (k coreKind) String() string {
|
||||
switch k {
|
||||
case reloFieldByteOffset:
|
||||
return "byte_off"
|
||||
case reloFieldByteSize:
|
||||
return "byte_sz"
|
||||
case reloFieldExists:
|
||||
return "field_exists"
|
||||
case reloFieldSigned:
|
||||
return "signed"
|
||||
case reloFieldLShiftU64:
|
||||
return "lshift_u64"
|
||||
case reloFieldRShiftU64:
|
||||
return "rshift_u64"
|
||||
case reloTypeIDLocal:
|
||||
return "local_type_id"
|
||||
case reloTypeIDTarget:
|
||||
return "target_type_id"
|
||||
case reloTypeExists:
|
||||
return "type_exists"
|
||||
case reloTypeSize:
|
||||
return "type_size"
|
||||
case reloEnumvalExists:
|
||||
return "enumval_exists"
|
||||
case reloEnumvalValue:
|
||||
return "enumval_value"
|
||||
default:
|
||||
return "unknown"
|
||||
}
|
||||
}
|
||||
|
||||
// CORERelocate calculates the difference in types between local and target.
|
||||
//
|
||||
// Returns a list of fixups which can be applied to instructions to make them
|
||||
// match the target type(s).
|
||||
//
|
||||
// Fixups are returned in the order of relos, e.g. fixup[i] is the solution
|
||||
// for relos[i].
|
||||
func CORERelocate(local, target *Spec, relos []*CORERelocation) ([]COREFixup, error) {
|
||||
if local.byteOrder != target.byteOrder {
|
||||
return nil, fmt.Errorf("can't relocate %s against %s", local.byteOrder, target.byteOrder)
|
||||
}
|
||||
|
||||
type reloGroup struct {
|
||||
relos []*CORERelocation
|
||||
// Position of each relocation in relos.
|
||||
indices []int
|
||||
}
|
||||
|
||||
// Split relocations into per Type lists.
|
||||
relosByType := make(map[Type]*reloGroup)
|
||||
result := make([]COREFixup, len(relos))
|
||||
for i, relo := range relos {
|
||||
if relo.kind == reloTypeIDLocal {
|
||||
// Filtering out reloTypeIDLocal here makes our lives a lot easier
|
||||
// down the line, since it doesn't have a target at all.
|
||||
if len(relo.accessor) > 1 || relo.accessor[0] != 0 {
|
||||
return nil, fmt.Errorf("%s: unexpected accessor %v", relo.kind, relo.accessor)
|
||||
}
|
||||
|
||||
id, err := local.TypeID(relo.typ)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("%s: %w", relo.kind, err)
|
||||
}
|
||||
|
||||
result[i] = COREFixup{
|
||||
kind: relo.kind,
|
||||
local: uint32(id),
|
||||
target: uint32(id),
|
||||
}
|
||||
continue
|
||||
}
|
||||
|
||||
group, ok := relosByType[relo.typ]
|
||||
if !ok {
|
||||
group = &reloGroup{}
|
||||
relosByType[relo.typ] = group
|
||||
}
|
||||
group.relos = append(group.relos, relo)
|
||||
group.indices = append(group.indices, i)
|
||||
}
|
||||
|
||||
for localType, group := range relosByType {
|
||||
localTypeName := localType.TypeName()
|
||||
if localTypeName == "" {
|
||||
return nil, fmt.Errorf("relocate unnamed or anonymous type %s: %w", localType, ErrNotSupported)
|
||||
}
|
||||
|
||||
targets := target.namedTypes[newEssentialName(localTypeName)]
|
||||
fixups, err := coreCalculateFixups(local, target, localType, targets, group.relos)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("relocate %s: %w", localType, err)
|
||||
}
|
||||
|
||||
for j, index := range group.indices {
|
||||
result[index] = fixups[j]
|
||||
}
|
||||
}
|
||||
|
||||
return result, nil
|
||||
}
|
||||
|
||||
var errAmbiguousRelocation = errors.New("ambiguous relocation")
|
||||
var errImpossibleRelocation = errors.New("impossible relocation")
|
||||
|
||||
// coreCalculateFixups calculates the fixups for the given relocations using
|
||||
// the "best" target.
|
||||
//
|
||||
// The best target is determined by scoring: the less poisoning we have to do
|
||||
// the better the target is.
|
||||
func coreCalculateFixups(localSpec, targetSpec *Spec, local Type, targets []Type, relos []*CORERelocation) ([]COREFixup, error) {
|
||||
localID, err := localSpec.TypeID(local)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("local type ID: %w", err)
|
||||
}
|
||||
local = Copy(local, UnderlyingType)
|
||||
|
||||
bestScore := len(relos)
|
||||
var bestFixups []COREFixup
|
||||
for i := range targets {
|
||||
targetID, err := targetSpec.TypeID(targets[i])
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("target type ID: %w", err)
|
||||
}
|
||||
target := Copy(targets[i], UnderlyingType)
|
||||
|
||||
score := 0 // lower is better
|
||||
fixups := make([]COREFixup, 0, len(relos))
|
||||
for _, relo := range relos {
|
||||
fixup, err := coreCalculateFixup(localSpec.byteOrder, local, localID, target, targetID, relo)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("target %s: %w", target, err)
|
||||
}
|
||||
if fixup.poison || fixup.isNonExistant() {
|
||||
score++
|
||||
}
|
||||
fixups = append(fixups, fixup)
|
||||
}
|
||||
|
||||
if score > bestScore {
|
||||
// We have a better target already, ignore this one.
|
||||
continue
|
||||
}
|
||||
|
||||
if score < bestScore {
|
||||
// This is the best target yet, use it.
|
||||
bestScore = score
|
||||
bestFixups = fixups
|
||||
continue
|
||||
}
|
||||
|
||||
// Some other target has the same score as the current one. Make sure
|
||||
// the fixups agree with each other.
|
||||
for i, fixup := range bestFixups {
|
||||
if !fixup.equal(fixups[i]) {
|
||||
return nil, fmt.Errorf("%s: multiple types match: %w", fixup.kind, errAmbiguousRelocation)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if bestFixups == nil {
|
||||
// Nothing at all matched, probably because there are no suitable
|
||||
// targets at all.
|
||||
//
|
||||
// Poison everything except checksForExistence.
|
||||
bestFixups = make([]COREFixup, len(relos))
|
||||
for i, relo := range relos {
|
||||
if relo.kind.checksForExistence() {
|
||||
bestFixups[i] = COREFixup{kind: relo.kind, local: 1, target: 0}
|
||||
} else {
|
||||
bestFixups[i] = COREFixup{kind: relo.kind, poison: true}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return bestFixups, nil
|
||||
}
|
||||
|
||||
// coreCalculateFixup calculates the fixup for a single local type, target type
|
||||
// and relocation.
|
||||
func coreCalculateFixup(byteOrder binary.ByteOrder, local Type, localID TypeID, target Type, targetID TypeID, relo *CORERelocation) (COREFixup, error) {
|
||||
fixup := func(local, target uint32) (COREFixup, error) {
|
||||
return COREFixup{kind: relo.kind, local: local, target: target}, nil
|
||||
}
|
||||
fixupWithoutValidation := func(local, target uint32) (COREFixup, error) {
|
||||
return COREFixup{kind: relo.kind, local: local, target: target, skipLocalValidation: true}, nil
|
||||
}
|
||||
poison := func() (COREFixup, error) {
|
||||
if relo.kind.checksForExistence() {
|
||||
return fixup(1, 0)
|
||||
}
|
||||
return COREFixup{kind: relo.kind, poison: true}, nil
|
||||
}
|
||||
zero := COREFixup{}
|
||||
|
||||
switch relo.kind {
|
||||
case reloTypeIDTarget, reloTypeSize, reloTypeExists:
|
||||
if len(relo.accessor) > 1 || relo.accessor[0] != 0 {
|
||||
return zero, fmt.Errorf("%s: unexpected accessor %v", relo.kind, relo.accessor)
|
||||
}
|
||||
|
||||
err := coreAreTypesCompatible(local, target)
|
||||
if errors.Is(err, errImpossibleRelocation) {
|
||||
return poison()
|
||||
}
|
||||
if err != nil {
|
||||
return zero, fmt.Errorf("relocation %s: %w", relo.kind, err)
|
||||
}
|
||||
|
||||
switch relo.kind {
|
||||
case reloTypeExists:
|
||||
return fixup(1, 1)
|
||||
|
||||
case reloTypeIDTarget:
|
||||
return fixup(uint32(localID), uint32(targetID))
|
||||
|
||||
case reloTypeSize:
|
||||
localSize, err := Sizeof(local)
|
||||
if err != nil {
|
||||
return zero, err
|
||||
}
|
||||
|
||||
targetSize, err := Sizeof(target)
|
||||
if err != nil {
|
||||
return zero, err
|
||||
}
|
||||
|
||||
return fixup(uint32(localSize), uint32(targetSize))
|
||||
}
|
||||
|
||||
case reloEnumvalValue, reloEnumvalExists:
|
||||
localValue, targetValue, err := coreFindEnumValue(local, relo.accessor, target)
|
||||
if errors.Is(err, errImpossibleRelocation) {
|
||||
return poison()
|
||||
}
|
||||
if err != nil {
|
||||
return zero, fmt.Errorf("relocation %s: %w", relo.kind, err)
|
||||
}
|
||||
|
||||
switch relo.kind {
|
||||
case reloEnumvalExists:
|
||||
return fixup(1, 1)
|
||||
|
||||
case reloEnumvalValue:
|
||||
return fixup(uint32(localValue.Value), uint32(targetValue.Value))
|
||||
}
|
||||
|
||||
case reloFieldSigned:
|
||||
switch local.(type) {
|
||||
case *Enum:
|
||||
return fixup(1, 1)
|
||||
case *Int:
|
||||
return fixup(
|
||||
uint32(local.(*Int).Encoding&Signed),
|
||||
uint32(target.(*Int).Encoding&Signed),
|
||||
)
|
||||
default:
|
||||
return fixupWithoutValidation(0, 0)
|
||||
}
|
||||
|
||||
case reloFieldByteOffset, reloFieldByteSize, reloFieldExists, reloFieldLShiftU64, reloFieldRShiftU64:
|
||||
if _, ok := target.(*Fwd); ok {
|
||||
// We can't relocate fields using a forward declaration, so
|
||||
// skip it. If a non-forward declaration is present in the BTF
|
||||
// we'll find it in one of the other iterations.
|
||||
return poison()
|
||||
}
|
||||
|
||||
localField, targetField, err := coreFindField(local, relo.accessor, target)
|
||||
if errors.Is(err, errImpossibleRelocation) {
|
||||
return poison()
|
||||
}
|
||||
if err != nil {
|
||||
return zero, fmt.Errorf("target %s: %w", target, err)
|
||||
}
|
||||
|
||||
maybeSkipValidation := func(f COREFixup, err error) (COREFixup, error) {
|
||||
f.skipLocalValidation = localField.bitfieldSize > 0
|
||||
return f, err
|
||||
}
|
||||
|
||||
switch relo.kind {
|
||||
case reloFieldExists:
|
||||
return fixup(1, 1)
|
||||
|
||||
case reloFieldByteOffset:
|
||||
return maybeSkipValidation(fixup(localField.offset, targetField.offset))
|
||||
|
||||
case reloFieldByteSize:
|
||||
localSize, err := Sizeof(localField.Type)
|
||||
if err != nil {
|
||||
return zero, err
|
||||
}
|
||||
|
||||
targetSize, err := Sizeof(targetField.Type)
|
||||
if err != nil {
|
||||
return zero, err
|
||||
}
|
||||
return maybeSkipValidation(fixup(uint32(localSize), uint32(targetSize)))
|
||||
|
||||
case reloFieldLShiftU64:
|
||||
var target uint32
|
||||
if byteOrder == binary.LittleEndian {
|
||||
targetSize, err := targetField.sizeBits()
|
||||
if err != nil {
|
||||
return zero, err
|
||||
}
|
||||
|
||||
target = uint32(64 - targetField.bitfieldOffset - targetSize)
|
||||
} else {
|
||||
loadWidth, err := Sizeof(targetField.Type)
|
||||
if err != nil {
|
||||
return zero, err
|
||||
}
|
||||
|
||||
target = uint32(64 - Bits(loadWidth*8) + targetField.bitfieldOffset)
|
||||
}
|
||||
return fixupWithoutValidation(0, target)
|
||||
|
||||
case reloFieldRShiftU64:
|
||||
targetSize, err := targetField.sizeBits()
|
||||
if err != nil {
|
||||
return zero, err
|
||||
}
|
||||
|
||||
return fixupWithoutValidation(0, uint32(64-targetSize))
|
||||
}
|
||||
}
|
||||
|
||||
return zero, fmt.Errorf("relocation %s: %w", relo.kind, ErrNotSupported)
|
||||
}
|
||||
|
||||
/* coreAccessor contains a path through a struct. It contains at least one index.
|
||||
*
|
||||
* The interpretation depends on the kind of the relocation. The following is
|
||||
* taken from struct bpf_core_relo in libbpf_internal.h:
|
||||
*
|
||||
* - for field-based relocations, string encodes an accessed field using
|
||||
* a sequence of field and array indices, separated by colon (:). It's
|
||||
* conceptually very close to LLVM's getelementptr ([0]) instruction's
|
||||
* arguments for identifying offset to a field.
|
||||
* - for type-based relocations, strings is expected to be just "0";
|
||||
* - for enum value-based relocations, string contains an index of enum
|
||||
* value within its enum type;
|
||||
*
|
||||
* Example to provide a better feel.
|
||||
*
|
||||
* struct sample {
|
||||
* int a;
|
||||
* struct {
|
||||
* int b[10];
|
||||
* };
|
||||
* };
|
||||
*
|
||||
* struct sample s = ...;
|
||||
* int x = &s->a; // encoded as "0:0" (a is field #0)
|
||||
* int y = &s->b[5]; // encoded as "0:1:0:5" (anon struct is field #1,
|
||||
* // b is field #0 inside anon struct, accessing elem #5)
|
||||
* int z = &s[10]->b; // encoded as "10:1" (ptr is used as an array)
|
||||
*/
|
||||
type coreAccessor []int
|
||||
|
||||
func parseCOREAccessor(accessor string) (coreAccessor, error) {
|
||||
if accessor == "" {
|
||||
return nil, fmt.Errorf("empty accessor")
|
||||
}
|
||||
|
||||
parts := strings.Split(accessor, ":")
|
||||
result := make(coreAccessor, 0, len(parts))
|
||||
for _, part := range parts {
|
||||
// 31 bits to avoid overflowing int on 32 bit platforms.
|
||||
index, err := strconv.ParseUint(part, 10, 31)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("accessor index %q: %s", part, err)
|
||||
}
|
||||
|
||||
result = append(result, int(index))
|
||||
}
|
||||
|
||||
return result, nil
|
||||
}
|
||||
|
||||
func (ca coreAccessor) String() string {
|
||||
strs := make([]string, 0, len(ca))
|
||||
for _, i := range ca {
|
||||
strs = append(strs, strconv.Itoa(i))
|
||||
}
|
||||
return strings.Join(strs, ":")
|
||||
}
|
||||
|
||||
func (ca coreAccessor) enumValue(t Type) (*EnumValue, error) {
|
||||
e, ok := t.(*Enum)
|
||||
if !ok {
|
||||
return nil, fmt.Errorf("not an enum: %s", t)
|
||||
}
|
||||
|
||||
if len(ca) > 1 {
|
||||
return nil, fmt.Errorf("invalid accessor %s for enum", ca)
|
||||
}
|
||||
|
||||
i := ca[0]
|
||||
if i >= len(e.Values) {
|
||||
return nil, fmt.Errorf("invalid index %d for %s", i, e)
|
||||
}
|
||||
|
||||
return &e.Values[i], nil
|
||||
}
|
||||
|
||||
// coreField represents the position of a "child" of a composite type from the
|
||||
// start of that type.
|
||||
//
|
||||
// /- start of composite
|
||||
// | offset * 8 | bitfieldOffset | bitfieldSize | ... |
|
||||
// \- start of field end of field -/
|
||||
type coreField struct {
|
||||
Type Type
|
||||
|
||||
// The position of the field from the start of the composite type in bytes.
|
||||
offset uint32
|
||||
|
||||
// The offset of the bitfield in bits from the start of the field.
|
||||
bitfieldOffset Bits
|
||||
|
||||
// The size of the bitfield in bits.
|
||||
//
|
||||
// Zero if the field is not a bitfield.
|
||||
bitfieldSize Bits
|
||||
}
|
||||
|
||||
func (cf *coreField) adjustOffsetToNthElement(n int) error {
|
||||
size, err := Sizeof(cf.Type)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
cf.offset += uint32(n) * uint32(size)
|
||||
return nil
|
||||
}
|
||||
|
||||
func (cf *coreField) adjustOffsetBits(offset Bits) error {
|
||||
align, err := alignof(cf.Type)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// We can compute the load offset by:
|
||||
// 1) converting the bit offset to bytes with a flooring division.
|
||||
// 2) dividing and multiplying that offset by the alignment, yielding the
|
||||
// load size aligned offset.
|
||||
offsetBytes := uint32(offset/8) / uint32(align) * uint32(align)
|
||||
|
||||
// The number of bits remaining is the bit offset less the number of bits
|
||||
// we can "skip" with the aligned offset.
|
||||
cf.bitfieldOffset = offset - Bits(offsetBytes*8)
|
||||
|
||||
// We know that cf.offset is aligned at to at least align since we get it
|
||||
// from the compiler via BTF. Adding an aligned offsetBytes preserves the
|
||||
// alignment.
|
||||
cf.offset += offsetBytes
|
||||
return nil
|
||||
}
|
||||
|
||||
func (cf *coreField) sizeBits() (Bits, error) {
|
||||
if cf.bitfieldSize > 0 {
|
||||
return cf.bitfieldSize, nil
|
||||
}
|
||||
|
||||
// Someone is trying to access a non-bitfield via a bit shift relocation.
|
||||
// This happens when a field changes from a bitfield to a regular field
|
||||
// between kernel versions. Synthesise the size to make the shifts work.
|
||||
size, err := Sizeof(cf.Type)
|
||||
if err != nil {
|
||||
return 0, nil
|
||||
}
|
||||
return Bits(size * 8), nil
|
||||
}
|
||||
|
||||
// coreFindField descends into the local type using the accessor and tries to
|
||||
// find an equivalent field in target at each step.
|
||||
//
|
||||
// Returns the field and the offset of the field from the start of
|
||||
// target in bits.
|
||||
func coreFindField(localT Type, localAcc coreAccessor, targetT Type) (coreField, coreField, error) {
|
||||
local := coreField{Type: localT}
|
||||
target := coreField{Type: targetT}
|
||||
|
||||
// The first index is used to offset a pointer of the base type like
|
||||
// when accessing an array.
|
||||
if err := local.adjustOffsetToNthElement(localAcc[0]); err != nil {
|
||||
return coreField{}, coreField{}, err
|
||||
}
|
||||
|
||||
if err := target.adjustOffsetToNthElement(localAcc[0]); err != nil {
|
||||
return coreField{}, coreField{}, err
|
||||
}
|
||||
|
||||
if err := coreAreMembersCompatible(local.Type, target.Type); err != nil {
|
||||
return coreField{}, coreField{}, fmt.Errorf("fields: %w", err)
|
||||
}
|
||||
|
||||
var localMaybeFlex, targetMaybeFlex bool
|
||||
for i, acc := range localAcc[1:] {
|
||||
switch localType := local.Type.(type) {
|
||||
case composite:
|
||||
// For composite types acc is used to find the field in the local type,
|
||||
// and then we try to find a field in target with the same name.
|
||||
localMembers := localType.members()
|
||||
if acc >= len(localMembers) {
|
||||
return coreField{}, coreField{}, fmt.Errorf("invalid accessor %d for %s", acc, localType)
|
||||
}
|
||||
|
||||
localMember := localMembers[acc]
|
||||
if localMember.Name == "" {
|
||||
_, ok := localMember.Type.(composite)
|
||||
if !ok {
|
||||
return coreField{}, coreField{}, fmt.Errorf("unnamed field with type %s: %s", localMember.Type, ErrNotSupported)
|
||||
}
|
||||
|
||||
// This is an anonymous struct or union, ignore it.
|
||||
local = coreField{
|
||||
Type: localMember.Type,
|
||||
offset: local.offset + localMember.Offset.Bytes(),
|
||||
}
|
||||
localMaybeFlex = false
|
||||
continue
|
||||
}
|
||||
|
||||
targetType, ok := target.Type.(composite)
|
||||
if !ok {
|
||||
return coreField{}, coreField{}, fmt.Errorf("target not composite: %w", errImpossibleRelocation)
|
||||
}
|
||||
|
||||
targetMember, last, err := coreFindMember(targetType, localMember.Name)
|
||||
if err != nil {
|
||||
return coreField{}, coreField{}, err
|
||||
}
|
||||
|
||||
local = coreField{
|
||||
Type: localMember.Type,
|
||||
offset: local.offset,
|
||||
bitfieldSize: localMember.BitfieldSize,
|
||||
}
|
||||
localMaybeFlex = acc == len(localMembers)-1
|
||||
|
||||
target = coreField{
|
||||
Type: targetMember.Type,
|
||||
offset: target.offset,
|
||||
bitfieldSize: targetMember.BitfieldSize,
|
||||
}
|
||||
targetMaybeFlex = last
|
||||
|
||||
if local.bitfieldSize == 0 && target.bitfieldSize == 0 {
|
||||
local.offset += localMember.Offset.Bytes()
|
||||
target.offset += targetMember.Offset.Bytes()
|
||||
break
|
||||
}
|
||||
|
||||
// Either of the members is a bitfield. Make sure we're at the
|
||||
// end of the accessor.
|
||||
if next := i + 1; next < len(localAcc[1:]) {
|
||||
return coreField{}, coreField{}, fmt.Errorf("can't descend into bitfield")
|
||||
}
|
||||
|
||||
if err := local.adjustOffsetBits(localMember.Offset); err != nil {
|
||||
return coreField{}, coreField{}, err
|
||||
}
|
||||
|
||||
if err := target.adjustOffsetBits(targetMember.Offset); err != nil {
|
||||
return coreField{}, coreField{}, err
|
||||
}
|
||||
|
||||
case *Array:
|
||||
// For arrays, acc is the index in the target.
|
||||
targetType, ok := target.Type.(*Array)
|
||||
if !ok {
|
||||
return coreField{}, coreField{}, fmt.Errorf("target not array: %w", errImpossibleRelocation)
|
||||
}
|
||||
|
||||
if localType.Nelems == 0 && !localMaybeFlex {
|
||||
return coreField{}, coreField{}, fmt.Errorf("local type has invalid flexible array")
|
||||
}
|
||||
if targetType.Nelems == 0 && !targetMaybeFlex {
|
||||
return coreField{}, coreField{}, fmt.Errorf("target type has invalid flexible array")
|
||||
}
|
||||
|
||||
if localType.Nelems > 0 && acc >= int(localType.Nelems) {
|
||||
return coreField{}, coreField{}, fmt.Errorf("invalid access of %s at index %d", localType, acc)
|
||||
}
|
||||
if targetType.Nelems > 0 && acc >= int(targetType.Nelems) {
|
||||
return coreField{}, coreField{}, fmt.Errorf("out of bounds access of target: %w", errImpossibleRelocation)
|
||||
}
|
||||
|
||||
local = coreField{
|
||||
Type: localType.Type,
|
||||
offset: local.offset,
|
||||
}
|
||||
localMaybeFlex = false
|
||||
|
||||
if err := local.adjustOffsetToNthElement(acc); err != nil {
|
||||
return coreField{}, coreField{}, err
|
||||
}
|
||||
|
||||
target = coreField{
|
||||
Type: targetType.Type,
|
||||
offset: target.offset,
|
||||
}
|
||||
targetMaybeFlex = false
|
||||
|
||||
if err := target.adjustOffsetToNthElement(acc); err != nil {
|
||||
return coreField{}, coreField{}, err
|
||||
}
|
||||
|
||||
default:
|
||||
return coreField{}, coreField{}, fmt.Errorf("relocate field of %T: %w", localType, ErrNotSupported)
|
||||
}
|
||||
|
||||
if err := coreAreMembersCompatible(local.Type, target.Type); err != nil {
|
||||
return coreField{}, coreField{}, err
|
||||
}
|
||||
}
|
||||
|
||||
return local, target, nil
|
||||
}
|
||||
|
||||
// coreFindMember finds a member in a composite type while handling anonymous
|
||||
// structs and unions.
|
||||
func coreFindMember(typ composite, name string) (Member, bool, error) {
|
||||
if name == "" {
|
||||
return Member{}, false, errors.New("can't search for anonymous member")
|
||||
}
|
||||
|
||||
type offsetTarget struct {
|
||||
composite
|
||||
offset Bits
|
||||
}
|
||||
|
||||
targets := []offsetTarget{{typ, 0}}
|
||||
visited := make(map[composite]bool)
|
||||
|
||||
for i := 0; i < len(targets); i++ {
|
||||
target := targets[i]
|
||||
|
||||
// Only visit targets once to prevent infinite recursion.
|
||||
if visited[target] {
|
||||
continue
|
||||
}
|
||||
if len(visited) >= maxTypeDepth {
|
||||
// This check is different than libbpf, which restricts the entire
|
||||
// path to BPF_CORE_SPEC_MAX_LEN items.
|
||||
return Member{}, false, fmt.Errorf("type is nested too deep")
|
||||
}
|
||||
visited[target] = true
|
||||
|
||||
members := target.members()
|
||||
for j, member := range members {
|
||||
if member.Name == name {
|
||||
// NB: This is safe because member is a copy.
|
||||
member.Offset += target.offset
|
||||
return member, j == len(members)-1, nil
|
||||
}
|
||||
|
||||
// The names don't match, but this member could be an anonymous struct
|
||||
// or union.
|
||||
if member.Name != "" {
|
||||
continue
|
||||
}
|
||||
|
||||
comp, ok := member.Type.(composite)
|
||||
if !ok {
|
||||
return Member{}, false, fmt.Errorf("anonymous non-composite type %T not allowed", member.Type)
|
||||
}
|
||||
|
||||
targets = append(targets, offsetTarget{comp, target.offset + member.Offset})
|
||||
}
|
||||
}
|
||||
|
||||
return Member{}, false, fmt.Errorf("no matching member: %w", errImpossibleRelocation)
|
||||
}
|
||||
|
||||
// coreFindEnumValue follows localAcc to find the equivalent enum value in target.
|
||||
func coreFindEnumValue(local Type, localAcc coreAccessor, target Type) (localValue, targetValue *EnumValue, _ error) {
|
||||
localValue, err := localAcc.enumValue(local)
|
||||
if err != nil {
|
||||
return nil, nil, err
|
||||
}
|
||||
|
||||
targetEnum, ok := target.(*Enum)
|
||||
if !ok {
|
||||
return nil, nil, errImpossibleRelocation
|
||||
}
|
||||
|
||||
localName := newEssentialName(localValue.Name)
|
||||
for i, targetValue := range targetEnum.Values {
|
||||
if newEssentialName(targetValue.Name) != localName {
|
||||
continue
|
||||
}
|
||||
|
||||
return localValue, &targetEnum.Values[i], nil
|
||||
}
|
||||
|
||||
return nil, nil, errImpossibleRelocation
|
||||
}
|
||||
|
||||
/* The comment below is from bpf_core_types_are_compat in libbpf.c:
|
||||
*
|
||||
* Check local and target types for compatibility. This check is used for
|
||||
* type-based CO-RE relocations and follow slightly different rules than
|
||||
* field-based relocations. This function assumes that root types were already
|
||||
* checked for name match. Beyond that initial root-level name check, names
|
||||
* are completely ignored. Compatibility rules are as follows:
|
||||
* - any two STRUCTs/UNIONs/FWDs/ENUMs/INTs are considered compatible, but
|
||||
* kind should match for local and target types (i.e., STRUCT is not
|
||||
* compatible with UNION);
|
||||
* - for ENUMs, the size is ignored;
|
||||
* - for INT, size and signedness are ignored;
|
||||
* - for ARRAY, dimensionality is ignored, element types are checked for
|
||||
* compatibility recursively;
|
||||
* - CONST/VOLATILE/RESTRICT modifiers are ignored;
|
||||
* - TYPEDEFs/PTRs are compatible if types they pointing to are compatible;
|
||||
* - FUNC_PROTOs are compatible if they have compatible signature: same
|
||||
* number of input args and compatible return and argument types.
|
||||
* These rules are not set in stone and probably will be adjusted as we get
|
||||
* more experience with using BPF CO-RE relocations.
|
||||
*
|
||||
* Returns errImpossibleRelocation if types are not compatible.
|
||||
*/
|
||||
func coreAreTypesCompatible(localType Type, targetType Type) error {
|
||||
var (
|
||||
localTs, targetTs typeDeque
|
||||
l, t = &localType, &targetType
|
||||
depth = 0
|
||||
)
|
||||
|
||||
for ; l != nil && t != nil; l, t = localTs.shift(), targetTs.shift() {
|
||||
if depth >= maxTypeDepth {
|
||||
return errors.New("types are nested too deep")
|
||||
}
|
||||
|
||||
localType = *l
|
||||
targetType = *t
|
||||
|
||||
if reflect.TypeOf(localType) != reflect.TypeOf(targetType) {
|
||||
return fmt.Errorf("type mismatch: %w", errImpossibleRelocation)
|
||||
}
|
||||
|
||||
switch lv := (localType).(type) {
|
||||
case *Void, *Struct, *Union, *Enum, *Fwd, *Int:
|
||||
// Nothing to do here
|
||||
|
||||
case *Pointer, *Array:
|
||||
depth++
|
||||
localType.walk(&localTs)
|
||||
targetType.walk(&targetTs)
|
||||
|
||||
case *FuncProto:
|
||||
tv := targetType.(*FuncProto)
|
||||
if len(lv.Params) != len(tv.Params) {
|
||||
return fmt.Errorf("function param mismatch: %w", errImpossibleRelocation)
|
||||
}
|
||||
|
||||
depth++
|
||||
localType.walk(&localTs)
|
||||
targetType.walk(&targetTs)
|
||||
|
||||
default:
|
||||
return fmt.Errorf("unsupported type %T", localType)
|
||||
}
|
||||
}
|
||||
|
||||
if l != nil {
|
||||
return fmt.Errorf("dangling local type %T", *l)
|
||||
}
|
||||
|
||||
if t != nil {
|
||||
return fmt.Errorf("dangling target type %T", *t)
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
/* coreAreMembersCompatible checks two types for field-based relocation compatibility.
|
||||
*
|
||||
* The comment below is from bpf_core_fields_are_compat in libbpf.c:
|
||||
*
|
||||
* Check two types for compatibility for the purpose of field access
|
||||
* relocation. const/volatile/restrict and typedefs are skipped to ensure we
|
||||
* are relocating semantically compatible entities:
|
||||
* - any two STRUCTs/UNIONs are compatible and can be mixed;
|
||||
* - any two FWDs are compatible, if their names match (modulo flavor suffix);
|
||||
* - any two PTRs are always compatible;
|
||||
* - for ENUMs, names should be the same (ignoring flavor suffix) or at
|
||||
* least one of enums should be anonymous;
|
||||
* - for ENUMs, check sizes, names are ignored;
|
||||
* - for INT, size and signedness are ignored;
|
||||
* - any two FLOATs are always compatible;
|
||||
* - for ARRAY, dimensionality is ignored, element types are checked for
|
||||
* compatibility recursively;
|
||||
* [ NB: coreAreMembersCompatible doesn't recurse, this check is done
|
||||
* by coreFindField. ]
|
||||
* - everything else shouldn't be ever a target of relocation.
|
||||
* These rules are not set in stone and probably will be adjusted as we get
|
||||
* more experience with using BPF CO-RE relocations.
|
||||
*
|
||||
* Returns errImpossibleRelocation if the members are not compatible.
|
||||
*/
|
||||
func coreAreMembersCompatible(localType Type, targetType Type) error {
|
||||
doNamesMatch := func(a, b string) error {
|
||||
if a == "" || b == "" {
|
||||
// allow anonymous and named type to match
|
||||
return nil
|
||||
}
|
||||
|
||||
if newEssentialName(a) == newEssentialName(b) {
|
||||
return nil
|
||||
}
|
||||
|
||||
return fmt.Errorf("names don't match: %w", errImpossibleRelocation)
|
||||
}
|
||||
|
||||
_, lok := localType.(composite)
|
||||
_, tok := targetType.(composite)
|
||||
if lok && tok {
|
||||
return nil
|
||||
}
|
||||
|
||||
if reflect.TypeOf(localType) != reflect.TypeOf(targetType) {
|
||||
return fmt.Errorf("type mismatch: %w", errImpossibleRelocation)
|
||||
}
|
||||
|
||||
switch lv := localType.(type) {
|
||||
case *Array, *Pointer, *Float, *Int:
|
||||
return nil
|
||||
|
||||
case *Enum:
|
||||
tv := targetType.(*Enum)
|
||||
return doNamesMatch(lv.Name, tv.Name)
|
||||
|
||||
case *Fwd:
|
||||
tv := targetType.(*Fwd)
|
||||
return doNamesMatch(lv.Name, tv.Name)
|
||||
|
||||
default:
|
||||
return fmt.Errorf("type %s: %w", localType, ErrNotSupported)
|
||||
}
|
||||
}
|
|
@ -2,7 +2,4 @@
|
|||
//
|
||||
// The canonical documentation lives in the Linux kernel repository and is
|
||||
// available at https://www.kernel.org/doc/html/latest/bpf/btf.html
|
||||
//
|
||||
// The API is very much unstable. You should only use this via the main
|
||||
// ebpf library.
|
||||
package btf
|
|
@ -0,0 +1,721 @@
|
|||
package btf
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"encoding/binary"
|
||||
"errors"
|
||||
"fmt"
|
||||
"io"
|
||||
"math"
|
||||
"sort"
|
||||
|
||||
"github.com/cilium/ebpf/asm"
|
||||
"github.com/cilium/ebpf/internal"
|
||||
)
|
||||
|
||||
// ExtInfos contains ELF section metadata.
|
||||
type ExtInfos struct {
|
||||
// The slices are sorted by offset in ascending order.
|
||||
funcInfos map[string][]funcInfo
|
||||
lineInfos map[string][]lineInfo
|
||||
relocationInfos map[string][]coreRelocationInfo
|
||||
}
|
||||
|
||||
// loadExtInfosFromELF parses ext infos from the .BTF.ext section in an ELF.
|
||||
//
|
||||
// Returns an error wrapping ErrNotFound if no ext infos are present.
|
||||
func loadExtInfosFromELF(file *internal.SafeELFFile, ts types, strings *stringTable) (*ExtInfos, error) {
|
||||
section := file.Section(".BTF.ext")
|
||||
if section == nil {
|
||||
return nil, fmt.Errorf("btf ext infos: %w", ErrNotFound)
|
||||
}
|
||||
|
||||
if section.ReaderAt == nil {
|
||||
return nil, fmt.Errorf("compressed ext_info is not supported")
|
||||
}
|
||||
|
||||
return loadExtInfos(section.ReaderAt, file.ByteOrder, ts, strings)
|
||||
}
|
||||
|
||||
// loadExtInfos parses bare ext infos.
|
||||
func loadExtInfos(r io.ReaderAt, bo binary.ByteOrder, ts types, strings *stringTable) (*ExtInfos, error) {
|
||||
// Open unbuffered section reader. binary.Read() calls io.ReadFull on
|
||||
// the header structs, resulting in one syscall per header.
|
||||
headerRd := io.NewSectionReader(r, 0, math.MaxInt64)
|
||||
extHeader, err := parseBTFExtHeader(headerRd, bo)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("parsing BTF extension header: %w", err)
|
||||
}
|
||||
|
||||
coreHeader, err := parseBTFExtCOREHeader(headerRd, bo, extHeader)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("parsing BTF CO-RE header: %w", err)
|
||||
}
|
||||
|
||||
buf := internal.NewBufferedSectionReader(r, extHeader.funcInfoStart(), int64(extHeader.FuncInfoLen))
|
||||
btfFuncInfos, err := parseFuncInfos(buf, bo, strings)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("parsing BTF function info: %w", err)
|
||||
}
|
||||
|
||||
funcInfos := make(map[string][]funcInfo, len(btfFuncInfos))
|
||||
for section, bfis := range btfFuncInfos {
|
||||
funcInfos[section], err = newFuncInfos(bfis, ts)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("section %s: func infos: %w", section, err)
|
||||
}
|
||||
}
|
||||
|
||||
buf = internal.NewBufferedSectionReader(r, extHeader.lineInfoStart(), int64(extHeader.LineInfoLen))
|
||||
btfLineInfos, err := parseLineInfos(buf, bo, strings)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("parsing BTF line info: %w", err)
|
||||
}
|
||||
|
||||
lineInfos := make(map[string][]lineInfo, len(btfLineInfos))
|
||||
for section, blis := range btfLineInfos {
|
||||
lineInfos[section], err = newLineInfos(blis, strings)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("section %s: line infos: %w", section, err)
|
||||
}
|
||||
}
|
||||
|
||||
if coreHeader == nil || coreHeader.COREReloLen == 0 {
|
||||
return &ExtInfos{funcInfos, lineInfos, nil}, nil
|
||||
}
|
||||
|
||||
var btfCORERelos map[string][]bpfCORERelo
|
||||
buf = internal.NewBufferedSectionReader(r, extHeader.coreReloStart(coreHeader), int64(coreHeader.COREReloLen))
|
||||
btfCORERelos, err = parseCORERelos(buf, bo, strings)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("parsing CO-RE relocation info: %w", err)
|
||||
}
|
||||
|
||||
coreRelos := make(map[string][]coreRelocationInfo, len(btfCORERelos))
|
||||
for section, brs := range btfCORERelos {
|
||||
coreRelos[section], err = newRelocationInfos(brs, ts, strings)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("section %s: CO-RE relocations: %w", section, err)
|
||||
}
|
||||
}
|
||||
|
||||
return &ExtInfos{funcInfos, lineInfos, coreRelos}, nil
|
||||
}
|
||||
|
||||
type funcInfoMeta struct{}
|
||||
type coreRelocationMeta struct{}
|
||||
|
||||
// Assign per-section metadata from BTF to a section's instructions.
|
||||
func (ei *ExtInfos) Assign(insns asm.Instructions, section string) {
|
||||
funcInfos := ei.funcInfos[section]
|
||||
lineInfos := ei.lineInfos[section]
|
||||
reloInfos := ei.relocationInfos[section]
|
||||
|
||||
iter := insns.Iterate()
|
||||
for iter.Next() {
|
||||
if len(funcInfos) > 0 && funcInfos[0].offset == iter.Offset {
|
||||
iter.Ins.Metadata.Set(funcInfoMeta{}, funcInfos[0].fn)
|
||||
funcInfos = funcInfos[1:]
|
||||
}
|
||||
|
||||
if len(lineInfos) > 0 && lineInfos[0].offset == iter.Offset {
|
||||
*iter.Ins = iter.Ins.WithSource(lineInfos[0].line)
|
||||
lineInfos = lineInfos[1:]
|
||||
}
|
||||
|
||||
if len(reloInfos) > 0 && reloInfos[0].offset == iter.Offset {
|
||||
iter.Ins.Metadata.Set(coreRelocationMeta{}, reloInfos[0].relo)
|
||||
reloInfos = reloInfos[1:]
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// MarshalExtInfos encodes function and line info embedded in insns into kernel
|
||||
// wire format.
|
||||
func MarshalExtInfos(insns asm.Instructions, typeID func(Type) (TypeID, error)) (funcInfos, lineInfos []byte, _ error) {
|
||||
iter := insns.Iterate()
|
||||
var fiBuf, liBuf bytes.Buffer
|
||||
for iter.Next() {
|
||||
if fn := FuncMetadata(iter.Ins); fn != nil {
|
||||
fi := &funcInfo{
|
||||
fn: fn,
|
||||
offset: iter.Offset,
|
||||
}
|
||||
if err := fi.marshal(&fiBuf, typeID); err != nil {
|
||||
return nil, nil, fmt.Errorf("write func info: %w", err)
|
||||
}
|
||||
}
|
||||
|
||||
if line, ok := iter.Ins.Source().(*Line); ok {
|
||||
li := &lineInfo{
|
||||
line: line,
|
||||
offset: iter.Offset,
|
||||
}
|
||||
if err := li.marshal(&liBuf); err != nil {
|
||||
return nil, nil, fmt.Errorf("write line info: %w", err)
|
||||
}
|
||||
}
|
||||
}
|
||||
return fiBuf.Bytes(), liBuf.Bytes(), nil
|
||||
}
|
||||
|
||||
// btfExtHeader is found at the start of the .BTF.ext section.
|
||||
type btfExtHeader struct {
|
||||
Magic uint16
|
||||
Version uint8
|
||||
Flags uint8
|
||||
|
||||
// HdrLen is larger than the size of struct btfExtHeader when it is
|
||||
// immediately followed by a btfExtCOREHeader.
|
||||
HdrLen uint32
|
||||
|
||||
FuncInfoOff uint32
|
||||
FuncInfoLen uint32
|
||||
LineInfoOff uint32
|
||||
LineInfoLen uint32
|
||||
}
|
||||
|
||||
// parseBTFExtHeader parses the header of the .BTF.ext section.
|
||||
func parseBTFExtHeader(r io.Reader, bo binary.ByteOrder) (*btfExtHeader, error) {
|
||||
var header btfExtHeader
|
||||
if err := binary.Read(r, bo, &header); err != nil {
|
||||
return nil, fmt.Errorf("can't read header: %v", err)
|
||||
}
|
||||
|
||||
if header.Magic != btfMagic {
|
||||
return nil, fmt.Errorf("incorrect magic value %v", header.Magic)
|
||||
}
|
||||
|
||||
if header.Version != 1 {
|
||||
return nil, fmt.Errorf("unexpected version %v", header.Version)
|
||||
}
|
||||
|
||||
if header.Flags != 0 {
|
||||
return nil, fmt.Errorf("unsupported flags %v", header.Flags)
|
||||
}
|
||||
|
||||
if int64(header.HdrLen) < int64(binary.Size(&header)) {
|
||||
return nil, fmt.Errorf("header length shorter than btfExtHeader size")
|
||||
}
|
||||
|
||||
return &header, nil
|
||||
}
|
||||
|
||||
// funcInfoStart returns the offset from the beginning of the .BTF.ext section
|
||||
// to the start of its func_info entries.
|
||||
func (h *btfExtHeader) funcInfoStart() int64 {
|
||||
return int64(h.HdrLen + h.FuncInfoOff)
|
||||
}
|
||||
|
||||
// lineInfoStart returns the offset from the beginning of the .BTF.ext section
|
||||
// to the start of its line_info entries.
|
||||
func (h *btfExtHeader) lineInfoStart() int64 {
|
||||
return int64(h.HdrLen + h.LineInfoOff)
|
||||
}
|
||||
|
||||
// coreReloStart returns the offset from the beginning of the .BTF.ext section
|
||||
// to the start of its CO-RE relocation entries.
|
||||
func (h *btfExtHeader) coreReloStart(ch *btfExtCOREHeader) int64 {
|
||||
return int64(h.HdrLen + ch.COREReloOff)
|
||||
}
|
||||
|
||||
// btfExtCOREHeader is found right after the btfExtHeader when its HdrLen
|
||||
// field is larger than its size.
|
||||
type btfExtCOREHeader struct {
|
||||
COREReloOff uint32
|
||||
COREReloLen uint32
|
||||
}
|
||||
|
||||
// parseBTFExtCOREHeader parses the tail of the .BTF.ext header. If additional
|
||||
// header bytes are present, extHeader.HdrLen will be larger than the struct,
|
||||
// indicating the presence of a CO-RE extension header.
|
||||
func parseBTFExtCOREHeader(r io.Reader, bo binary.ByteOrder, extHeader *btfExtHeader) (*btfExtCOREHeader, error) {
|
||||
extHdrSize := int64(binary.Size(&extHeader))
|
||||
remainder := int64(extHeader.HdrLen) - extHdrSize
|
||||
|
||||
if remainder == 0 {
|
||||
return nil, nil
|
||||
}
|
||||
|
||||
var coreHeader btfExtCOREHeader
|
||||
if err := binary.Read(r, bo, &coreHeader); err != nil {
|
||||
return nil, fmt.Errorf("can't read header: %v", err)
|
||||
}
|
||||
|
||||
return &coreHeader, nil
|
||||
}
|
||||
|
||||
type btfExtInfoSec struct {
|
||||
SecNameOff uint32
|
||||
NumInfo uint32
|
||||
}
|
||||
|
||||
// parseExtInfoSec parses a btf_ext_info_sec header within .BTF.ext,
|
||||
// appearing within func_info and line_info sub-sections.
|
||||
// These headers appear once for each program section in the ELF and are
|
||||
// followed by one or more func/line_info records for the section.
|
||||
func parseExtInfoSec(r io.Reader, bo binary.ByteOrder, strings *stringTable) (string, *btfExtInfoSec, error) {
|
||||
var infoHeader btfExtInfoSec
|
||||
if err := binary.Read(r, bo, &infoHeader); err != nil {
|
||||
return "", nil, fmt.Errorf("read ext info header: %w", err)
|
||||
}
|
||||
|
||||
secName, err := strings.Lookup(infoHeader.SecNameOff)
|
||||
if err != nil {
|
||||
return "", nil, fmt.Errorf("get section name: %w", err)
|
||||
}
|
||||
if secName == "" {
|
||||
return "", nil, fmt.Errorf("extinfo header refers to empty section name")
|
||||
}
|
||||
|
||||
if infoHeader.NumInfo == 0 {
|
||||
return "", nil, fmt.Errorf("section %s has zero records", secName)
|
||||
}
|
||||
|
||||
return secName, &infoHeader, nil
|
||||
}
|
||||
|
||||
// parseExtInfoRecordSize parses the uint32 at the beginning of a func_infos
|
||||
// or line_infos segment that describes the length of all extInfoRecords in
|
||||
// that segment.
|
||||
func parseExtInfoRecordSize(r io.Reader, bo binary.ByteOrder) (uint32, error) {
|
||||
const maxRecordSize = 256
|
||||
|
||||
var recordSize uint32
|
||||
if err := binary.Read(r, bo, &recordSize); err != nil {
|
||||
return 0, fmt.Errorf("can't read record size: %v", err)
|
||||
}
|
||||
|
||||
if recordSize < 4 {
|
||||
// Need at least InsnOff worth of bytes per record.
|
||||
return 0, errors.New("record size too short")
|
||||
}
|
||||
if recordSize > maxRecordSize {
|
||||
return 0, fmt.Errorf("record size %v exceeds %v", recordSize, maxRecordSize)
|
||||
}
|
||||
|
||||
return recordSize, nil
|
||||
}
|
||||
|
||||
// The size of a FuncInfo in BTF wire format.
|
||||
var FuncInfoSize = uint32(binary.Size(bpfFuncInfo{}))
|
||||
|
||||
type funcInfo struct {
|
||||
fn *Func
|
||||
offset asm.RawInstructionOffset
|
||||
}
|
||||
|
||||
type bpfFuncInfo struct {
|
||||
// Instruction offset of the function within an ELF section.
|
||||
InsnOff uint32
|
||||
TypeID TypeID
|
||||
}
|
||||
|
||||
func newFuncInfo(fi bpfFuncInfo, ts types) (*funcInfo, error) {
|
||||
typ, err := ts.ByID(fi.TypeID)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
fn, ok := typ.(*Func)
|
||||
if !ok {
|
||||
return nil, fmt.Errorf("type ID %d is a %T, but expected a Func", fi.TypeID, typ)
|
||||
}
|
||||
|
||||
// C doesn't have anonymous functions, but check just in case.
|
||||
if fn.Name == "" {
|
||||
return nil, fmt.Errorf("func with type ID %d doesn't have a name", fi.TypeID)
|
||||
}
|
||||
|
||||
return &funcInfo{
|
||||
fn,
|
||||
asm.RawInstructionOffset(fi.InsnOff),
|
||||
}, nil
|
||||
}
|
||||
|
||||
func newFuncInfos(bfis []bpfFuncInfo, ts types) ([]funcInfo, error) {
|
||||
fis := make([]funcInfo, 0, len(bfis))
|
||||
for _, bfi := range bfis {
|
||||
fi, err := newFuncInfo(bfi, ts)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("offset %d: %w", bfi.InsnOff, err)
|
||||
}
|
||||
fis = append(fis, *fi)
|
||||
}
|
||||
sort.Slice(fis, func(i, j int) bool {
|
||||
return fis[i].offset <= fis[j].offset
|
||||
})
|
||||
return fis, nil
|
||||
}
|
||||
|
||||
// marshal into the BTF wire format.
|
||||
func (fi *funcInfo) marshal(w io.Writer, typeID func(Type) (TypeID, error)) error {
|
||||
id, err := typeID(fi.fn)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
bfi := bpfFuncInfo{
|
||||
InsnOff: uint32(fi.offset),
|
||||
TypeID: id,
|
||||
}
|
||||
return binary.Write(w, internal.NativeEndian, &bfi)
|
||||
}
|
||||
|
||||
// parseLineInfos parses a func_info sub-section within .BTF.ext ito a map of
|
||||
// func infos indexed by section name.
|
||||
func parseFuncInfos(r io.Reader, bo binary.ByteOrder, strings *stringTable) (map[string][]bpfFuncInfo, error) {
|
||||
recordSize, err := parseExtInfoRecordSize(r, bo)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
result := make(map[string][]bpfFuncInfo)
|
||||
for {
|
||||
secName, infoHeader, err := parseExtInfoSec(r, bo, strings)
|
||||
if errors.Is(err, io.EOF) {
|
||||
return result, nil
|
||||
}
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
records, err := parseFuncInfoRecords(r, bo, recordSize, infoHeader.NumInfo)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("section %v: %w", secName, err)
|
||||
}
|
||||
|
||||
result[secName] = records
|
||||
}
|
||||
}
|
||||
|
||||
// parseFuncInfoRecords parses a stream of func_infos into a funcInfos.
|
||||
// These records appear after a btf_ext_info_sec header in the func_info
|
||||
// sub-section of .BTF.ext.
|
||||
func parseFuncInfoRecords(r io.Reader, bo binary.ByteOrder, recordSize uint32, recordNum uint32) ([]bpfFuncInfo, error) {
|
||||
var out []bpfFuncInfo
|
||||
var fi bpfFuncInfo
|
||||
|
||||
if exp, got := FuncInfoSize, recordSize; exp != got {
|
||||
// BTF blob's record size is longer than we know how to parse.
|
||||
return nil, fmt.Errorf("expected FuncInfo record size %d, but BTF blob contains %d", exp, got)
|
||||
}
|
||||
|
||||
for i := uint32(0); i < recordNum; i++ {
|
||||
if err := binary.Read(r, bo, &fi); err != nil {
|
||||
return nil, fmt.Errorf("can't read function info: %v", err)
|
||||
}
|
||||
|
||||
if fi.InsnOff%asm.InstructionSize != 0 {
|
||||
return nil, fmt.Errorf("offset %v is not aligned with instruction size", fi.InsnOff)
|
||||
}
|
||||
|
||||
// ELF tracks offset in bytes, the kernel expects raw BPF instructions.
|
||||
// Convert as early as possible.
|
||||
fi.InsnOff /= asm.InstructionSize
|
||||
|
||||
out = append(out, fi)
|
||||
}
|
||||
|
||||
return out, nil
|
||||
}
|
||||
|
||||
var LineInfoSize = uint32(binary.Size(bpfLineInfo{}))
|
||||
|
||||
// Line represents the location and contents of a single line of source
|
||||
// code a BPF ELF was compiled from.
|
||||
type Line struct {
|
||||
fileName string
|
||||
line string
|
||||
lineNumber uint32
|
||||
lineColumn uint32
|
||||
|
||||
// TODO: We should get rid of the fields below, but for that we need to be
|
||||
// able to write BTF.
|
||||
|
||||
fileNameOff uint32
|
||||
lineOff uint32
|
||||
}
|
||||
|
||||
func (li *Line) FileName() string {
|
||||
return li.fileName
|
||||
}
|
||||
|
||||
func (li *Line) Line() string {
|
||||
return li.line
|
||||
}
|
||||
|
||||
func (li *Line) LineNumber() uint32 {
|
||||
return li.lineNumber
|
||||
}
|
||||
|
||||
func (li *Line) LineColumn() uint32 {
|
||||
return li.lineColumn
|
||||
}
|
||||
|
||||
func (li *Line) String() string {
|
||||
return li.line
|
||||
}
|
||||
|
||||
type lineInfo struct {
|
||||
line *Line
|
||||
offset asm.RawInstructionOffset
|
||||
}
|
||||
|
||||
// Constants for the format of bpfLineInfo.LineCol.
|
||||
const (
|
||||
bpfLineShift = 10
|
||||
bpfLineMax = (1 << (32 - bpfLineShift)) - 1
|
||||
bpfColumnMax = (1 << bpfLineShift) - 1
|
||||
)
|
||||
|
||||
type bpfLineInfo struct {
|
||||
// Instruction offset of the line within the whole instruction stream, in instructions.
|
||||
InsnOff uint32
|
||||
FileNameOff uint32
|
||||
LineOff uint32
|
||||
LineCol uint32
|
||||
}
|
||||
|
||||
func newLineInfo(li bpfLineInfo, strings *stringTable) (*lineInfo, error) {
|
||||
line, err := strings.Lookup(li.LineOff)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("lookup of line: %w", err)
|
||||
}
|
||||
|
||||
fileName, err := strings.Lookup(li.FileNameOff)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("lookup of filename: %w", err)
|
||||
}
|
||||
|
||||
lineNumber := li.LineCol >> bpfLineShift
|
||||
lineColumn := li.LineCol & bpfColumnMax
|
||||
|
||||
return &lineInfo{
|
||||
&Line{
|
||||
fileName,
|
||||
line,
|
||||
lineNumber,
|
||||
lineColumn,
|
||||
li.FileNameOff,
|
||||
li.LineOff,
|
||||
},
|
||||
asm.RawInstructionOffset(li.InsnOff),
|
||||
}, nil
|
||||
}
|
||||
|
||||
func newLineInfos(blis []bpfLineInfo, strings *stringTable) ([]lineInfo, error) {
|
||||
lis := make([]lineInfo, 0, len(blis))
|
||||
for _, bli := range blis {
|
||||
li, err := newLineInfo(bli, strings)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("offset %d: %w", bli.InsnOff, err)
|
||||
}
|
||||
lis = append(lis, *li)
|
||||
}
|
||||
sort.Slice(lis, func(i, j int) bool {
|
||||
return lis[i].offset <= lis[j].offset
|
||||
})
|
||||
return lis, nil
|
||||
}
|
||||
|
||||
// marshal writes the binary representation of the LineInfo to w.
|
||||
func (li *lineInfo) marshal(w io.Writer) error {
|
||||
line := li.line
|
||||
if line.lineNumber > bpfLineMax {
|
||||
return fmt.Errorf("line %d exceeds %d", line.lineNumber, bpfLineMax)
|
||||
}
|
||||
|
||||
if line.lineColumn > bpfColumnMax {
|
||||
return fmt.Errorf("column %d exceeds %d", line.lineColumn, bpfColumnMax)
|
||||
}
|
||||
|
||||
bli := bpfLineInfo{
|
||||
uint32(li.offset),
|
||||
line.fileNameOff,
|
||||
line.lineOff,
|
||||
(line.lineNumber << bpfLineShift) | line.lineColumn,
|
||||
}
|
||||
return binary.Write(w, internal.NativeEndian, &bli)
|
||||
}
|
||||
|
||||
// parseLineInfos parses a line_info sub-section within .BTF.ext ito a map of
|
||||
// line infos indexed by section name.
|
||||
func parseLineInfos(r io.Reader, bo binary.ByteOrder, strings *stringTable) (map[string][]bpfLineInfo, error) {
|
||||
recordSize, err := parseExtInfoRecordSize(r, bo)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
result := make(map[string][]bpfLineInfo)
|
||||
for {
|
||||
secName, infoHeader, err := parseExtInfoSec(r, bo, strings)
|
||||
if errors.Is(err, io.EOF) {
|
||||
return result, nil
|
||||
}
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
records, err := parseLineInfoRecords(r, bo, recordSize, infoHeader.NumInfo)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("section %v: %w", secName, err)
|
||||
}
|
||||
|
||||
result[secName] = records
|
||||
}
|
||||
}
|
||||
|
||||
// parseLineInfoRecords parses a stream of line_infos into a lineInfos.
|
||||
// These records appear after a btf_ext_info_sec header in the line_info
|
||||
// sub-section of .BTF.ext.
|
||||
func parseLineInfoRecords(r io.Reader, bo binary.ByteOrder, recordSize uint32, recordNum uint32) ([]bpfLineInfo, error) {
|
||||
var out []bpfLineInfo
|
||||
var li bpfLineInfo
|
||||
|
||||
if exp, got := uint32(binary.Size(li)), recordSize; exp != got {
|
||||
// BTF blob's record size is longer than we know how to parse.
|
||||
return nil, fmt.Errorf("expected LineInfo record size %d, but BTF blob contains %d", exp, got)
|
||||
}
|
||||
|
||||
for i := uint32(0); i < recordNum; i++ {
|
||||
if err := binary.Read(r, bo, &li); err != nil {
|
||||
return nil, fmt.Errorf("can't read line info: %v", err)
|
||||
}
|
||||
|
||||
if li.InsnOff%asm.InstructionSize != 0 {
|
||||
return nil, fmt.Errorf("offset %v is not aligned with instruction size", li.InsnOff)
|
||||
}
|
||||
|
||||
// ELF tracks offset in bytes, the kernel expects raw BPF instructions.
|
||||
// Convert as early as possible.
|
||||
li.InsnOff /= asm.InstructionSize
|
||||
|
||||
out = append(out, li)
|
||||
}
|
||||
|
||||
return out, nil
|
||||
}
|
||||
|
||||
// bpfCORERelo matches the kernel's struct bpf_core_relo.
|
||||
type bpfCORERelo struct {
|
||||
InsnOff uint32
|
||||
TypeID TypeID
|
||||
AccessStrOff uint32
|
||||
Kind coreKind
|
||||
}
|
||||
|
||||
type CORERelocation struct {
|
||||
typ Type
|
||||
accessor coreAccessor
|
||||
kind coreKind
|
||||
}
|
||||
|
||||
func CORERelocationMetadata(ins *asm.Instruction) *CORERelocation {
|
||||
relo, _ := ins.Metadata.Get(coreRelocationMeta{}).(*CORERelocation)
|
||||
return relo
|
||||
}
|
||||
|
||||
type coreRelocationInfo struct {
|
||||
relo *CORERelocation
|
||||
offset asm.RawInstructionOffset
|
||||
}
|
||||
|
||||
func newRelocationInfo(relo bpfCORERelo, ts types, strings *stringTable) (*coreRelocationInfo, error) {
|
||||
typ, err := ts.ByID(relo.TypeID)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
accessorStr, err := strings.Lookup(relo.AccessStrOff)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
accessor, err := parseCOREAccessor(accessorStr)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("accessor %q: %s", accessorStr, err)
|
||||
}
|
||||
|
||||
return &coreRelocationInfo{
|
||||
&CORERelocation{
|
||||
typ,
|
||||
accessor,
|
||||
relo.Kind,
|
||||
},
|
||||
asm.RawInstructionOffset(relo.InsnOff),
|
||||
}, nil
|
||||
}
|
||||
|
||||
func newRelocationInfos(brs []bpfCORERelo, ts types, strings *stringTable) ([]coreRelocationInfo, error) {
|
||||
rs := make([]coreRelocationInfo, 0, len(brs))
|
||||
for _, br := range brs {
|
||||
relo, err := newRelocationInfo(br, ts, strings)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("offset %d: %w", br.InsnOff, err)
|
||||
}
|
||||
rs = append(rs, *relo)
|
||||
}
|
||||
sort.Slice(rs, func(i, j int) bool {
|
||||
return rs[i].offset < rs[j].offset
|
||||
})
|
||||
return rs, nil
|
||||
}
|
||||
|
||||
var extInfoReloSize = binary.Size(bpfCORERelo{})
|
||||
|
||||
// parseCORERelos parses a core_relos sub-section within .BTF.ext ito a map of
|
||||
// CO-RE relocations indexed by section name.
|
||||
func parseCORERelos(r io.Reader, bo binary.ByteOrder, strings *stringTable) (map[string][]bpfCORERelo, error) {
|
||||
recordSize, err := parseExtInfoRecordSize(r, bo)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
if recordSize != uint32(extInfoReloSize) {
|
||||
return nil, fmt.Errorf("expected record size %d, got %d", extInfoReloSize, recordSize)
|
||||
}
|
||||
|
||||
result := make(map[string][]bpfCORERelo)
|
||||
for {
|
||||
secName, infoHeader, err := parseExtInfoSec(r, bo, strings)
|
||||
if errors.Is(err, io.EOF) {
|
||||
return result, nil
|
||||
}
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
records, err := parseCOREReloRecords(r, bo, recordSize, infoHeader.NumInfo)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("section %v: %w", secName, err)
|
||||
}
|
||||
|
||||
result[secName] = records
|
||||
}
|
||||
}
|
||||
|
||||
// parseCOREReloRecords parses a stream of CO-RE relocation entries into a
|
||||
// coreRelos. These records appear after a btf_ext_info_sec header in the
|
||||
// core_relos sub-section of .BTF.ext.
|
||||
func parseCOREReloRecords(r io.Reader, bo binary.ByteOrder, recordSize uint32, recordNum uint32) ([]bpfCORERelo, error) {
|
||||
var out []bpfCORERelo
|
||||
|
||||
var relo bpfCORERelo
|
||||
for i := uint32(0); i < recordNum; i++ {
|
||||
if err := binary.Read(r, bo, &relo); err != nil {
|
||||
return nil, fmt.Errorf("can't read CO-RE relocation: %v", err)
|
||||
}
|
||||
|
||||
if relo.InsnOff%asm.InstructionSize != 0 {
|
||||
return nil, fmt.Errorf("offset %v is not aligned with instruction size", relo.InsnOff)
|
||||
}
|
||||
|
||||
// ELF tracks offset in bytes, the kernel expects raw BPF instructions.
|
||||
// Convert as early as possible.
|
||||
relo.InsnOff /= asm.InstructionSize
|
||||
|
||||
out = append(out, relo)
|
||||
}
|
||||
|
||||
return out, nil
|
||||
}
|
|
@ -0,0 +1,319 @@
|
|||
package btf
|
||||
|
||||
import (
|
||||
"errors"
|
||||
"fmt"
|
||||
"strings"
|
||||
)
|
||||
|
||||
var errNestedTooDeep = errors.New("nested too deep")
|
||||
|
||||
// GoFormatter converts a Type to Go syntax.
|
||||
//
|
||||
// A zero GoFormatter is valid to use.
|
||||
type GoFormatter struct {
|
||||
w strings.Builder
|
||||
|
||||
// Types present in this map are referred to using the given name if they
|
||||
// are encountered when outputting another type.
|
||||
Names map[Type]string
|
||||
|
||||
// Identifier is called for each field of struct-like types. By default the
|
||||
// field name is used as is.
|
||||
Identifier func(string) string
|
||||
|
||||
// EnumIdentifier is called for each element of an enum. By default the
|
||||
// name of the enum type is concatenated with Identifier(element).
|
||||
EnumIdentifier func(name, element string) string
|
||||
}
|
||||
|
||||
// TypeDeclaration generates a Go type declaration for a BTF type.
|
||||
func (gf *GoFormatter) TypeDeclaration(name string, typ Type) (string, error) {
|
||||
gf.w.Reset()
|
||||
if err := gf.writeTypeDecl(name, typ); err != nil {
|
||||
return "", err
|
||||
}
|
||||
return gf.w.String(), nil
|
||||
}
|
||||
|
||||
func (gf *GoFormatter) identifier(s string) string {
|
||||
if gf.Identifier != nil {
|
||||
return gf.Identifier(s)
|
||||
}
|
||||
|
||||
return s
|
||||
}
|
||||
|
||||
func (gf *GoFormatter) enumIdentifier(name, element string) string {
|
||||
if gf.EnumIdentifier != nil {
|
||||
return gf.EnumIdentifier(name, element)
|
||||
}
|
||||
|
||||
return name + gf.identifier(element)
|
||||
}
|
||||
|
||||
// writeTypeDecl outputs a declaration of the given type.
|
||||
//
|
||||
// It encodes https://golang.org/ref/spec#Type_declarations:
|
||||
//
|
||||
// type foo struct { bar uint32; }
|
||||
// type bar int32
|
||||
func (gf *GoFormatter) writeTypeDecl(name string, typ Type) error {
|
||||
if name == "" {
|
||||
return fmt.Errorf("need a name for type %s", typ)
|
||||
}
|
||||
|
||||
switch v := skipQualifiers(typ).(type) {
|
||||
case *Enum:
|
||||
fmt.Fprintf(&gf.w, "type %s ", name)
|
||||
switch v.Size {
|
||||
case 1:
|
||||
gf.w.WriteString("int8")
|
||||
case 2:
|
||||
gf.w.WriteString("int16")
|
||||
case 4:
|
||||
gf.w.WriteString("int32")
|
||||
case 8:
|
||||
gf.w.WriteString("int64")
|
||||
default:
|
||||
return fmt.Errorf("%s: invalid enum size %d", typ, v.Size)
|
||||
}
|
||||
|
||||
if len(v.Values) == 0 {
|
||||
return nil
|
||||
}
|
||||
|
||||
gf.w.WriteString("; const ( ")
|
||||
for _, ev := range v.Values {
|
||||
id := gf.enumIdentifier(name, ev.Name)
|
||||
fmt.Fprintf(&gf.w, "%s %s = %d; ", id, name, ev.Value)
|
||||
}
|
||||
gf.w.WriteString(")")
|
||||
|
||||
return nil
|
||||
|
||||
default:
|
||||
fmt.Fprintf(&gf.w, "type %s ", name)
|
||||
return gf.writeTypeLit(v, 0)
|
||||
}
|
||||
}
|
||||
|
||||
// writeType outputs the name of a named type or a literal describing the type.
|
||||
//
|
||||
// It encodes https://golang.org/ref/spec#Types.
|
||||
//
|
||||
// foo (if foo is a named type)
|
||||
// uint32
|
||||
func (gf *GoFormatter) writeType(typ Type, depth int) error {
|
||||
typ = skipQualifiers(typ)
|
||||
|
||||
name := gf.Names[typ]
|
||||
if name != "" {
|
||||
gf.w.WriteString(name)
|
||||
return nil
|
||||
}
|
||||
|
||||
return gf.writeTypeLit(typ, depth)
|
||||
}
|
||||
|
||||
// writeTypeLit outputs a literal describing the type.
|
||||
//
|
||||
// The function ignores named types.
|
||||
//
|
||||
// It encodes https://golang.org/ref/spec#TypeLit.
|
||||
//
|
||||
// struct { bar uint32; }
|
||||
// uint32
|
||||
func (gf *GoFormatter) writeTypeLit(typ Type, depth int) error {
|
||||
depth++
|
||||
if depth > maxTypeDepth {
|
||||
return errNestedTooDeep
|
||||
}
|
||||
|
||||
var err error
|
||||
switch v := skipQualifiers(typ).(type) {
|
||||
case *Int:
|
||||
gf.writeIntLit(v)
|
||||
|
||||
case *Enum:
|
||||
gf.w.WriteString("int32")
|
||||
|
||||
case *Typedef:
|
||||
err = gf.writeType(v.Type, depth)
|
||||
|
||||
case *Array:
|
||||
fmt.Fprintf(&gf.w, "[%d]", v.Nelems)
|
||||
err = gf.writeType(v.Type, depth)
|
||||
|
||||
case *Struct:
|
||||
err = gf.writeStructLit(v.Size, v.Members, depth)
|
||||
|
||||
case *Union:
|
||||
// Always choose the first member to represent the union in Go.
|
||||
err = gf.writeStructLit(v.Size, v.Members[:1], depth)
|
||||
|
||||
case *Datasec:
|
||||
err = gf.writeDatasecLit(v, depth)
|
||||
|
||||
default:
|
||||
return fmt.Errorf("type %T: %w", v, ErrNotSupported)
|
||||
}
|
||||
|
||||
if err != nil {
|
||||
return fmt.Errorf("%s: %w", typ, err)
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
func (gf *GoFormatter) writeIntLit(i *Int) {
|
||||
// NB: Encoding.IsChar is ignored.
|
||||
if i.Encoding.IsBool() && i.Size == 1 {
|
||||
gf.w.WriteString("bool")
|
||||
return
|
||||
}
|
||||
|
||||
bits := i.Size * 8
|
||||
if i.Encoding.IsSigned() {
|
||||
fmt.Fprintf(&gf.w, "int%d", bits)
|
||||
} else {
|
||||
fmt.Fprintf(&gf.w, "uint%d", bits)
|
||||
}
|
||||
}
|
||||
|
||||
func (gf *GoFormatter) writeStructLit(size uint32, members []Member, depth int) error {
|
||||
gf.w.WriteString("struct { ")
|
||||
|
||||
prevOffset := uint32(0)
|
||||
skippedBitfield := false
|
||||
for i, m := range members {
|
||||
if m.BitfieldSize > 0 {
|
||||
skippedBitfield = true
|
||||
continue
|
||||
}
|
||||
|
||||
offset := m.Offset.Bytes()
|
||||
if n := offset - prevOffset; skippedBitfield && n > 0 {
|
||||
fmt.Fprintf(&gf.w, "_ [%d]byte /* unsupported bitfield */; ", n)
|
||||
} else {
|
||||
gf.writePadding(n)
|
||||
}
|
||||
|
||||
size, err := Sizeof(m.Type)
|
||||
if err != nil {
|
||||
return fmt.Errorf("field %d: %w", i, err)
|
||||
}
|
||||
prevOffset = offset + uint32(size)
|
||||
|
||||
if err := gf.writeStructField(m, depth); err != nil {
|
||||
return fmt.Errorf("field %d: %w", i, err)
|
||||
}
|
||||
}
|
||||
|
||||
gf.writePadding(size - prevOffset)
|
||||
gf.w.WriteString("}")
|
||||
return nil
|
||||
}
|
||||
|
||||
func (gf *GoFormatter) writeStructField(m Member, depth int) error {
|
||||
if m.BitfieldSize > 0 {
|
||||
return fmt.Errorf("bitfields are not supported")
|
||||
}
|
||||
if m.Offset%8 != 0 {
|
||||
return fmt.Errorf("unsupported offset %d", m.Offset)
|
||||
}
|
||||
|
||||
if m.Name == "" {
|
||||
// Special case a nested anonymous union like
|
||||
// struct foo { union { int bar; int baz }; }
|
||||
// by replacing the whole union with its first member.
|
||||
union, ok := m.Type.(*Union)
|
||||
if !ok {
|
||||
return fmt.Errorf("anonymous fields are not supported")
|
||||
|
||||
}
|
||||
|
||||
if len(union.Members) == 0 {
|
||||
return errors.New("empty anonymous union")
|
||||
}
|
||||
|
||||
depth++
|
||||
if depth > maxTypeDepth {
|
||||
return errNestedTooDeep
|
||||
}
|
||||
|
||||
m := union.Members[0]
|
||||
size, err := Sizeof(m.Type)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
if err := gf.writeStructField(m, depth); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
gf.writePadding(union.Size - uint32(size))
|
||||
return nil
|
||||
|
||||
}
|
||||
|
||||
fmt.Fprintf(&gf.w, "%s ", gf.identifier(m.Name))
|
||||
|
||||
if err := gf.writeType(m.Type, depth); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
gf.w.WriteString("; ")
|
||||
return nil
|
||||
}
|
||||
|
||||
func (gf *GoFormatter) writeDatasecLit(ds *Datasec, depth int) error {
|
||||
gf.w.WriteString("struct { ")
|
||||
|
||||
prevOffset := uint32(0)
|
||||
for i, vsi := range ds.Vars {
|
||||
v := vsi.Type.(*Var)
|
||||
if v.Linkage != GlobalVar {
|
||||
// Ignore static, extern, etc. for now.
|
||||
continue
|
||||
}
|
||||
|
||||
if v.Name == "" {
|
||||
return fmt.Errorf("variable %d: empty name", i)
|
||||
}
|
||||
|
||||
gf.writePadding(vsi.Offset - prevOffset)
|
||||
prevOffset = vsi.Offset + vsi.Size
|
||||
|
||||
fmt.Fprintf(&gf.w, "%s ", gf.identifier(v.Name))
|
||||
|
||||
if err := gf.writeType(v.Type, depth); err != nil {
|
||||
return fmt.Errorf("variable %d: %w", i, err)
|
||||
}
|
||||
|
||||
gf.w.WriteString("; ")
|
||||
}
|
||||
|
||||
gf.writePadding(ds.Size - prevOffset)
|
||||
gf.w.WriteString("}")
|
||||
return nil
|
||||
}
|
||||
|
||||
func (gf *GoFormatter) writePadding(bytes uint32) {
|
||||
if bytes > 0 {
|
||||
fmt.Fprintf(&gf.w, "_ [%d]byte; ", bytes)
|
||||
}
|
||||
}
|
||||
|
||||
func skipQualifiers(typ Type) Type {
|
||||
result := typ
|
||||
for depth := 0; depth <= maxTypeDepth; depth++ {
|
||||
switch v := (result).(type) {
|
||||
case qualifier:
|
||||
result = v.qualify()
|
||||
default:
|
||||
return result
|
||||
}
|
||||
}
|
||||
return &cycle{typ}
|
||||
}
|
|
@ -0,0 +1,121 @@
|
|||
package btf
|
||||
|
||||
import (
|
||||
"errors"
|
||||
"fmt"
|
||||
"os"
|
||||
|
||||
"github.com/cilium/ebpf/internal/sys"
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
// HandleInfo describes a Handle.
|
||||
type HandleInfo struct {
|
||||
// ID of this handle in the kernel. The ID is only valid as long as the
|
||||
// associated handle is kept alive.
|
||||
ID ID
|
||||
|
||||
// Name is an identifying name for the BTF, currently only used by the
|
||||
// kernel.
|
||||
Name string
|
||||
|
||||
// IsKernel is true if the BTF originated with the kernel and not
|
||||
// userspace.
|
||||
IsKernel bool
|
||||
|
||||
// Size of the raw BTF in bytes.
|
||||
size uint32
|
||||
}
|
||||
|
||||
func newHandleInfoFromFD(fd *sys.FD) (*HandleInfo, error) {
|
||||
// We invoke the syscall once with a empty BTF and name buffers to get size
|
||||
// information to allocate buffers. Then we invoke it a second time with
|
||||
// buffers to receive the data.
|
||||
var btfInfo sys.BtfInfo
|
||||
if err := sys.ObjInfo(fd, &btfInfo); err != nil {
|
||||
return nil, fmt.Errorf("get BTF info for fd %s: %w", fd, err)
|
||||
}
|
||||
|
||||
if btfInfo.NameLen > 0 {
|
||||
// NameLen doesn't account for the terminating NUL.
|
||||
btfInfo.NameLen++
|
||||
}
|
||||
|
||||
// Don't pull raw BTF by default, since it may be quite large.
|
||||
btfSize := btfInfo.BtfSize
|
||||
btfInfo.BtfSize = 0
|
||||
|
||||
nameBuffer := make([]byte, btfInfo.NameLen)
|
||||
btfInfo.Name, btfInfo.NameLen = sys.NewSlicePointerLen(nameBuffer)
|
||||
if err := sys.ObjInfo(fd, &btfInfo); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return &HandleInfo{
|
||||
ID: ID(btfInfo.Id),
|
||||
Name: unix.ByteSliceToString(nameBuffer),
|
||||
IsKernel: btfInfo.KernelBtf != 0,
|
||||
size: btfSize,
|
||||
}, nil
|
||||
}
|
||||
|
||||
// IsModule returns true if the BTF is for the kernel itself.
|
||||
func (i *HandleInfo) IsVmlinux() bool {
|
||||
return i.IsKernel && i.Name == "vmlinux"
|
||||
}
|
||||
|
||||
// IsModule returns true if the BTF is for a kernel module.
|
||||
func (i *HandleInfo) IsModule() bool {
|
||||
return i.IsKernel && i.Name != "vmlinux"
|
||||
}
|
||||
|
||||
// HandleIterator allows enumerating BTF blobs loaded into the kernel.
|
||||
type HandleIterator struct {
|
||||
// The ID of the last retrieved handle. Only valid after a call to Next.
|
||||
ID ID
|
||||
err error
|
||||
}
|
||||
|
||||
// Next retrieves a handle for the next BTF blob.
|
||||
//
|
||||
// [Handle.Close] is called if *handle is non-nil to avoid leaking fds.
|
||||
//
|
||||
// Returns true if another BTF blob was found. Call [HandleIterator.Err] after
|
||||
// the function returns false.
|
||||
func (it *HandleIterator) Next(handle **Handle) bool {
|
||||
if *handle != nil {
|
||||
(*handle).Close()
|
||||
*handle = nil
|
||||
}
|
||||
|
||||
id := it.ID
|
||||
for {
|
||||
attr := &sys.BtfGetNextIdAttr{Id: id}
|
||||
err := sys.BtfGetNextId(attr)
|
||||
if errors.Is(err, os.ErrNotExist) {
|
||||
// There are no more BTF objects.
|
||||
return false
|
||||
} else if err != nil {
|
||||
it.err = fmt.Errorf("get next BTF ID: %w", err)
|
||||
return false
|
||||
}
|
||||
|
||||
id = attr.NextId
|
||||
*handle, err = NewHandleFromID(id)
|
||||
if errors.Is(err, os.ErrNotExist) {
|
||||
// Try again with the next ID.
|
||||
continue
|
||||
} else if err != nil {
|
||||
it.err = fmt.Errorf("retrieve handle for ID %d: %w", id, err)
|
||||
return false
|
||||
}
|
||||
|
||||
it.ID = id
|
||||
return true
|
||||
}
|
||||
}
|
||||
|
||||
// Err returns an error if iteration failed for some reason.
|
||||
func (it *HandleIterator) Err() error {
|
||||
return it.err
|
||||
}
|
|
@ -0,0 +1,128 @@
|
|||
package btf
|
||||
|
||||
import (
|
||||
"bufio"
|
||||
"bytes"
|
||||
"errors"
|
||||
"fmt"
|
||||
"io"
|
||||
)
|
||||
|
||||
type stringTable struct {
|
||||
base *stringTable
|
||||
offsets []uint32
|
||||
strings []string
|
||||
}
|
||||
|
||||
// sizedReader is implemented by bytes.Reader, io.SectionReader, strings.Reader, etc.
|
||||
type sizedReader interface {
|
||||
io.Reader
|
||||
Size() int64
|
||||
}
|
||||
|
||||
func readStringTable(r sizedReader, base *stringTable) (*stringTable, error) {
|
||||
// When parsing split BTF's string table, the first entry offset is derived
|
||||
// from the last entry offset of the base BTF.
|
||||
firstStringOffset := uint32(0)
|
||||
if base != nil {
|
||||
idx := len(base.offsets) - 1
|
||||
firstStringOffset = base.offsets[idx] + uint32(len(base.strings[idx])) + 1
|
||||
}
|
||||
|
||||
// Derived from vmlinux BTF.
|
||||
const averageStringLength = 16
|
||||
|
||||
n := int(r.Size() / averageStringLength)
|
||||
offsets := make([]uint32, 0, n)
|
||||
strings := make([]string, 0, n)
|
||||
|
||||
offset := firstStringOffset
|
||||
scanner := bufio.NewScanner(r)
|
||||
scanner.Split(splitNull)
|
||||
for scanner.Scan() {
|
||||
str := scanner.Text()
|
||||
offsets = append(offsets, offset)
|
||||
strings = append(strings, str)
|
||||
offset += uint32(len(str)) + 1
|
||||
}
|
||||
if err := scanner.Err(); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
if len(strings) == 0 {
|
||||
return nil, errors.New("string table is empty")
|
||||
}
|
||||
|
||||
if firstStringOffset == 0 && strings[0] != "" {
|
||||
return nil, errors.New("first item in string table is non-empty")
|
||||
}
|
||||
|
||||
return &stringTable{base, offsets, strings}, nil
|
||||
}
|
||||
|
||||
func splitNull(data []byte, atEOF bool) (advance int, token []byte, err error) {
|
||||
i := bytes.IndexByte(data, 0)
|
||||
if i == -1 {
|
||||
if atEOF && len(data) > 0 {
|
||||
return 0, nil, errors.New("string table isn't null terminated")
|
||||
}
|
||||
return 0, nil, nil
|
||||
}
|
||||
|
||||
return i + 1, data[:i], nil
|
||||
}
|
||||
|
||||
func (st *stringTable) Lookup(offset uint32) (string, error) {
|
||||
if st.base != nil && offset <= st.base.offsets[len(st.base.offsets)-1] {
|
||||
return st.base.lookup(offset)
|
||||
}
|
||||
return st.lookup(offset)
|
||||
}
|
||||
|
||||
func (st *stringTable) lookup(offset uint32) (string, error) {
|
||||
i := search(st.offsets, offset)
|
||||
if i == len(st.offsets) || st.offsets[i] != offset {
|
||||
return "", fmt.Errorf("offset %d isn't start of a string", offset)
|
||||
}
|
||||
|
||||
return st.strings[i], nil
|
||||
}
|
||||
|
||||
func (st *stringTable) Length() int {
|
||||
last := len(st.offsets) - 1
|
||||
return int(st.offsets[last]) + len(st.strings[last]) + 1
|
||||
}
|
||||
|
||||
func (st *stringTable) Marshal(w io.Writer) error {
|
||||
for _, str := range st.strings {
|
||||
_, err := io.WriteString(w, str)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
_, err = w.Write([]byte{0})
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// search is a copy of sort.Search specialised for uint32.
|
||||
//
|
||||
// Licensed under https://go.dev/LICENSE
|
||||
func search(ints []uint32, needle uint32) int {
|
||||
// Define f(-1) == false and f(n) == true.
|
||||
// Invariant: f(i-1) == false, f(j) == true.
|
||||
i, j := 0, len(ints)
|
||||
for i < j {
|
||||
h := int(uint(i+j) >> 1) // avoid overflow when computing h
|
||||
// i ≤ h < j
|
||||
if !(ints[h] >= needle) {
|
||||
i = h + 1 // preserves f(i-1) == false
|
||||
} else {
|
||||
j = h // preserves f(j) == true
|
||||
}
|
||||
}
|
||||
// i == j, f(i-1) == false, and f(j) (= f(i)) == true => answer is i.
|
||||
return i
|
||||
}
|
File diff suppressed because it is too large
Load Diff
|
@ -1,15 +1,14 @@
|
|||
package ebpf
|
||||
|
||||
import (
|
||||
"encoding/binary"
|
||||
"errors"
|
||||
"fmt"
|
||||
"math"
|
||||
"reflect"
|
||||
"strings"
|
||||
|
||||
"github.com/cilium/ebpf/asm"
|
||||
"github.com/cilium/ebpf/internal"
|
||||
"github.com/cilium/ebpf/internal/btf"
|
||||
"github.com/cilium/ebpf/btf"
|
||||
)
|
||||
|
||||
// CollectionOptions control loading a collection into the kernel.
|
||||
|
@ -18,12 +17,31 @@ import (
|
|||
type CollectionOptions struct {
|
||||
Maps MapOptions
|
||||
Programs ProgramOptions
|
||||
|
||||
// MapReplacements takes a set of Maps that will be used instead of
|
||||
// creating new ones when loading the CollectionSpec.
|
||||
//
|
||||
// For each given Map, there must be a corresponding MapSpec in
|
||||
// CollectionSpec.Maps, and its type, key/value size, max entries and flags
|
||||
// must match the values of the MapSpec.
|
||||
//
|
||||
// The given Maps are Clone()d before being used in the Collection, so the
|
||||
// caller can Close() them freely when they are no longer needed.
|
||||
MapReplacements map[string]*Map
|
||||
}
|
||||
|
||||
// CollectionSpec describes a collection.
|
||||
type CollectionSpec struct {
|
||||
Maps map[string]*MapSpec
|
||||
Programs map[string]*ProgramSpec
|
||||
|
||||
// Types holds type information about Maps and Programs.
|
||||
// Modifications to Types are currently undefined behaviour.
|
||||
Types *btf.Spec
|
||||
|
||||
// ByteOrder specifies whether the ELF was compiled for
|
||||
// big-endian or little-endian architectures.
|
||||
ByteOrder binary.ByteOrder
|
||||
}
|
||||
|
||||
// Copy returns a recursive copy of the spec.
|
||||
|
@ -35,6 +53,8 @@ func (cs *CollectionSpec) Copy() *CollectionSpec {
|
|||
cpy := CollectionSpec{
|
||||
Maps: make(map[string]*MapSpec, len(cs.Maps)),
|
||||
Programs: make(map[string]*ProgramSpec, len(cs.Programs)),
|
||||
ByteOrder: cs.ByteOrder,
|
||||
Types: cs.Types,
|
||||
}
|
||||
|
||||
for name, spec := range cs.Maps {
|
||||
|
@ -54,19 +74,21 @@ func (cs *CollectionSpec) Copy() *CollectionSpec {
|
|||
// when calling NewCollection. Any named maps are removed from CollectionSpec.Maps.
|
||||
//
|
||||
// Returns an error if a named map isn't used in at least one program.
|
||||
//
|
||||
// Deprecated: Pass CollectionOptions.MapReplacements when loading the Collection
|
||||
// instead.
|
||||
func (cs *CollectionSpec) RewriteMaps(maps map[string]*Map) error {
|
||||
for symbol, m := range maps {
|
||||
// have we seen a program that uses this symbol / map
|
||||
seen := false
|
||||
fd := m.FD()
|
||||
for progName, progSpec := range cs.Programs {
|
||||
err := progSpec.Instructions.RewriteMapPtr(symbol, fd)
|
||||
err := progSpec.Instructions.AssociateMap(symbol, m)
|
||||
|
||||
switch {
|
||||
case err == nil:
|
||||
seen = true
|
||||
|
||||
case asm.IsUnreferencedSymbol(err):
|
||||
case errors.Is(err, asm.ErrUnreferencedSymbol):
|
||||
// Not all programs need to use the map
|
||||
|
||||
default:
|
||||
|
@ -89,8 +111,8 @@ func (cs *CollectionSpec) RewriteMaps(maps map[string]*Map) error {
|
|||
//
|
||||
// The constant must be defined like so in the C program:
|
||||
//
|
||||
// static volatile const type foobar;
|
||||
// static volatile const type foobar = default;
|
||||
// volatile const type foobar;
|
||||
// volatile const type foobar = default;
|
||||
//
|
||||
// Replacement values must be of the same length as the C sizeof(type).
|
||||
// If necessary, they are marshalled according to the same rules as
|
||||
|
@ -100,48 +122,81 @@ func (cs *CollectionSpec) RewriteMaps(maps map[string]*Map) error {
|
|||
//
|
||||
// Returns an error if a constant doesn't exist.
|
||||
func (cs *CollectionSpec) RewriteConstants(consts map[string]interface{}) error {
|
||||
rodata := cs.Maps[".rodata"]
|
||||
if rodata == nil {
|
||||
return errors.New("missing .rodata section")
|
||||
replaced := make(map[string]bool)
|
||||
|
||||
for name, spec := range cs.Maps {
|
||||
if !strings.HasPrefix(name, ".rodata") {
|
||||
continue
|
||||
}
|
||||
|
||||
if rodata.BTF == nil {
|
||||
return errors.New(".rodata section has no BTF")
|
||||
b, ds, err := spec.dataSection()
|
||||
if errors.Is(err, errMapNoBTFValue) {
|
||||
// Data sections without a BTF Datasec are valid, but don't support
|
||||
// constant replacements.
|
||||
continue
|
||||
}
|
||||
|
||||
if n := len(rodata.Contents); n != 1 {
|
||||
return fmt.Errorf("expected one key in .rodata, found %d", n)
|
||||
}
|
||||
|
||||
kv := rodata.Contents[0]
|
||||
value, ok := kv.Value.([]byte)
|
||||
if !ok {
|
||||
return fmt.Errorf("first value in .rodata is %T not []byte", kv.Value)
|
||||
}
|
||||
|
||||
buf := make([]byte, len(value))
|
||||
copy(buf, value)
|
||||
|
||||
err := patchValue(buf, btf.MapValue(rodata.BTF), consts)
|
||||
if err != nil {
|
||||
return err
|
||||
return fmt.Errorf("map %s: %w", name, err)
|
||||
}
|
||||
|
||||
// MapSpec.Copy() performs a shallow copy. Fully copy the byte slice
|
||||
// to avoid any changes affecting other copies of the MapSpec.
|
||||
cpy := make([]byte, len(b))
|
||||
copy(cpy, b)
|
||||
|
||||
for _, v := range ds.Vars {
|
||||
vname := v.Type.TypeName()
|
||||
replacement, ok := consts[vname]
|
||||
if !ok {
|
||||
continue
|
||||
}
|
||||
|
||||
if replaced[vname] {
|
||||
return fmt.Errorf("section %s: duplicate variable %s", name, vname)
|
||||
}
|
||||
|
||||
if int(v.Offset+v.Size) > len(cpy) {
|
||||
return fmt.Errorf("section %s: offset %d(+%d) for variable %s is out of bounds", name, v.Offset, v.Size, vname)
|
||||
}
|
||||
|
||||
b, err := marshalBytes(replacement, int(v.Size))
|
||||
if err != nil {
|
||||
return fmt.Errorf("marshaling constant replacement %s: %w", vname, err)
|
||||
}
|
||||
|
||||
copy(cpy[v.Offset:v.Offset+v.Size], b)
|
||||
|
||||
replaced[vname] = true
|
||||
}
|
||||
|
||||
spec.Contents[0] = MapKV{Key: uint32(0), Value: cpy}
|
||||
}
|
||||
|
||||
var missing []string
|
||||
for c := range consts {
|
||||
if !replaced[c] {
|
||||
missing = append(missing, c)
|
||||
}
|
||||
}
|
||||
|
||||
if len(missing) != 0 {
|
||||
return fmt.Errorf("spec is missing one or more constants: %s", strings.Join(missing, ","))
|
||||
}
|
||||
|
||||
rodata.Contents[0] = MapKV{kv.Key, buf}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Assign the contents of a CollectionSpec to a struct.
|
||||
//
|
||||
// This function is a short-cut to manually checking the presence
|
||||
// of maps and programs in a collection spec. Consider using bpf2go if this
|
||||
// sounds useful.
|
||||
// This function is a shortcut to manually checking the presence
|
||||
// of maps and programs in a CollectionSpec. Consider using bpf2go
|
||||
// if this sounds useful.
|
||||
//
|
||||
// The argument to must be a pointer to a struct. A field of the
|
||||
// 'to' must be a pointer to a struct. A field of the
|
||||
// struct is updated with values from Programs or Maps if it
|
||||
// has an `ebpf` tag and its type is *ProgramSpec or *MapSpec.
|
||||
// The tag gives the name of the program or map as found in
|
||||
// the CollectionSpec.
|
||||
// The tag's value specifies the name of the program or map as
|
||||
// found in the CollectionSpec.
|
||||
//
|
||||
// struct {
|
||||
// Foo *ebpf.ProgramSpec `ebpf:"xdp_foo"`
|
||||
|
@ -149,42 +204,50 @@ func (cs *CollectionSpec) RewriteConstants(consts map[string]interface{}) error
|
|||
// Ignored int
|
||||
// }
|
||||
//
|
||||
// Returns an error if any of the fields can't be found, or
|
||||
// if the same map or program is assigned multiple times.
|
||||
// Returns an error if any of the eBPF objects can't be found, or
|
||||
// if the same MapSpec or ProgramSpec is assigned multiple times.
|
||||
func (cs *CollectionSpec) Assign(to interface{}) error {
|
||||
valueOf := func(typ reflect.Type, name string) (reflect.Value, error) {
|
||||
// Assign() only supports assigning ProgramSpecs and MapSpecs,
|
||||
// so doesn't load any resources into the kernel.
|
||||
getValue := func(typ reflect.Type, name string) (interface{}, error) {
|
||||
switch typ {
|
||||
|
||||
case reflect.TypeOf((*ProgramSpec)(nil)):
|
||||
p := cs.Programs[name]
|
||||
if p == nil {
|
||||
return reflect.Value{}, fmt.Errorf("missing program %q", name)
|
||||
if p := cs.Programs[name]; p != nil {
|
||||
return p, nil
|
||||
}
|
||||
return reflect.ValueOf(p), nil
|
||||
return nil, fmt.Errorf("missing program %q", name)
|
||||
|
||||
case reflect.TypeOf((*MapSpec)(nil)):
|
||||
m := cs.Maps[name]
|
||||
if m == nil {
|
||||
return reflect.Value{}, fmt.Errorf("missing map %q", name)
|
||||
if m := cs.Maps[name]; m != nil {
|
||||
return m, nil
|
||||
}
|
||||
return reflect.ValueOf(m), nil
|
||||
return nil, fmt.Errorf("missing map %q", name)
|
||||
|
||||
default:
|
||||
return reflect.Value{}, fmt.Errorf("unsupported type %s", typ)
|
||||
return nil, fmt.Errorf("unsupported type %s", typ)
|
||||
}
|
||||
}
|
||||
|
||||
return assignValues(to, valueOf)
|
||||
return assignValues(to, getValue)
|
||||
}
|
||||
|
||||
// LoadAndAssign maps and programs into the kernel and assign them to a struct.
|
||||
// LoadAndAssign loads Maps and Programs into the kernel and assigns them
|
||||
// to a struct.
|
||||
//
|
||||
// This function is a short-cut to manually checking the presence
|
||||
// of maps and programs in a collection spec. Consider using bpf2go if this
|
||||
// sounds useful.
|
||||
// Omitting Map/Program.Close() during application shutdown is an error.
|
||||
// See the package documentation for details around Map and Program lifecycle.
|
||||
//
|
||||
// The argument to must be a pointer to a struct. A field of the
|
||||
// struct is updated with values from Programs or Maps if it
|
||||
// has an `ebpf` tag and its type is *Program or *Map.
|
||||
// The tag gives the name of the program or map as found in
|
||||
// the CollectionSpec.
|
||||
// This function is a shortcut to manually checking the presence
|
||||
// of maps and programs in a CollectionSpec. Consider using bpf2go
|
||||
// if this sounds useful.
|
||||
//
|
||||
// 'to' must be a pointer to a struct. A field of the struct is updated with
|
||||
// a Program or Map if it has an `ebpf` tag and its type is *Program or *Map.
|
||||
// The tag's value specifies the name of the program or map as found in the
|
||||
// CollectionSpec. Before updating the struct, the requested objects and their
|
||||
// dependent resources are loaded into the kernel and populated with values if
|
||||
// specified.
|
||||
//
|
||||
// struct {
|
||||
// Foo *ebpf.Program `ebpf:"xdp_foo"`
|
||||
|
@ -195,39 +258,70 @@ func (cs *CollectionSpec) Assign(to interface{}) error {
|
|||
// opts may be nil.
|
||||
//
|
||||
// Returns an error if any of the fields can't be found, or
|
||||
// if the same map or program is assigned multiple times.
|
||||
// if the same Map or Program is assigned multiple times.
|
||||
func (cs *CollectionSpec) LoadAndAssign(to interface{}, opts *CollectionOptions) error {
|
||||
if opts == nil {
|
||||
opts = &CollectionOptions{}
|
||||
loader, err := newCollectionLoader(cs, opts)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
defer loader.close()
|
||||
|
||||
loadMap, loadProgram, done, cleanup := lazyLoadCollection(cs, opts)
|
||||
defer cleanup()
|
||||
// Support assigning Programs and Maps, lazy-loading the required objects.
|
||||
assignedMaps := make(map[string]bool)
|
||||
assignedProgs := make(map[string]bool)
|
||||
|
||||
valueOf := func(typ reflect.Type, name string) (reflect.Value, error) {
|
||||
getValue := func(typ reflect.Type, name string) (interface{}, error) {
|
||||
switch typ {
|
||||
|
||||
case reflect.TypeOf((*Program)(nil)):
|
||||
p, err := loadProgram(name)
|
||||
if err != nil {
|
||||
return reflect.Value{}, err
|
||||
}
|
||||
return reflect.ValueOf(p), nil
|
||||
assignedProgs[name] = true
|
||||
return loader.loadProgram(name)
|
||||
|
||||
case reflect.TypeOf((*Map)(nil)):
|
||||
m, err := loadMap(name)
|
||||
if err != nil {
|
||||
return reflect.Value{}, err
|
||||
}
|
||||
return reflect.ValueOf(m), nil
|
||||
assignedMaps[name] = true
|
||||
return loader.loadMap(name)
|
||||
|
||||
default:
|
||||
return reflect.Value{}, fmt.Errorf("unsupported type %s", typ)
|
||||
return nil, fmt.Errorf("unsupported type %s", typ)
|
||||
}
|
||||
}
|
||||
|
||||
if err := assignValues(to, valueOf); err != nil {
|
||||
// Load the Maps and Programs requested by the annotated struct.
|
||||
if err := assignValues(to, getValue); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
done()
|
||||
// Populate the requested maps. Has a chance of lazy-loading other dependent maps.
|
||||
if err := loader.populateMaps(); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// Evaluate the loader's objects after all (lazy)loading has taken place.
|
||||
for n, m := range loader.maps {
|
||||
switch m.typ {
|
||||
case ProgramArray:
|
||||
// Require all lazy-loaded ProgramArrays to be assigned to the given object.
|
||||
// The kernel empties a ProgramArray once the last user space reference
|
||||
// to it closes, which leads to failed tail calls. Combined with the library
|
||||
// closing map fds via GC finalizers this can lead to surprising behaviour.
|
||||
// Only allow unassigned ProgramArrays when the library hasn't pre-populated
|
||||
// any entries from static value declarations. At this point, we know the map
|
||||
// is empty and there's no way for the caller to interact with the map going
|
||||
// forward.
|
||||
if !assignedMaps[n] && len(cs.Maps[n].Contents) > 0 {
|
||||
return fmt.Errorf("ProgramArray %s must be assigned to prevent missed tail calls", n)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Prevent loader.cleanup() from closing assigned Maps and Programs.
|
||||
for m := range assignedMaps {
|
||||
delete(loader.maps, m)
|
||||
}
|
||||
for p := range assignedProgs {
|
||||
delete(loader.programs, p)
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
|
@ -238,42 +332,73 @@ type Collection struct {
|
|||
Maps map[string]*Map
|
||||
}
|
||||
|
||||
// NewCollection creates a Collection from a specification.
|
||||
// NewCollection creates a Collection from the given spec, creating and
|
||||
// loading its declared resources into the kernel.
|
||||
//
|
||||
// Omitting Collection.Close() during application shutdown is an error.
|
||||
// See the package documentation for details around Map and Program lifecycle.
|
||||
func NewCollection(spec *CollectionSpec) (*Collection, error) {
|
||||
return NewCollectionWithOptions(spec, CollectionOptions{})
|
||||
}
|
||||
|
||||
// NewCollectionWithOptions creates a Collection from a specification.
|
||||
// NewCollectionWithOptions creates a Collection from the given spec using
|
||||
// options, creating and loading its declared resources into the kernel.
|
||||
//
|
||||
// Omitting Collection.Close() during application shutdown is an error.
|
||||
// See the package documentation for details around Map and Program lifecycle.
|
||||
func NewCollectionWithOptions(spec *CollectionSpec, opts CollectionOptions) (*Collection, error) {
|
||||
loadMap, loadProgram, done, cleanup := lazyLoadCollection(spec, &opts)
|
||||
defer cleanup()
|
||||
loader, err := newCollectionLoader(spec, &opts)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
defer loader.close()
|
||||
|
||||
// Create maps first, as their fds need to be linked into programs.
|
||||
for mapName := range spec.Maps {
|
||||
_, err := loadMap(mapName)
|
||||
if err != nil {
|
||||
if _, err := loader.loadMap(mapName); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
}
|
||||
|
||||
for progName := range spec.Programs {
|
||||
_, err := loadProgram(progName)
|
||||
if err != nil {
|
||||
for progName, prog := range spec.Programs {
|
||||
if prog.Type == UnspecifiedProgram {
|
||||
continue
|
||||
}
|
||||
|
||||
if _, err := loader.loadProgram(progName); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
}
|
||||
|
||||
maps, progs := done()
|
||||
// Maps can contain Program and Map stubs, so populate them after
|
||||
// all Maps and Programs have been successfully loaded.
|
||||
if err := loader.populateMaps(); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// Prevent loader.cleanup from closing maps and programs.
|
||||
maps, progs := loader.maps, loader.programs
|
||||
loader.maps, loader.programs = nil, nil
|
||||
|
||||
return &Collection{
|
||||
progs,
|
||||
maps,
|
||||
}, nil
|
||||
}
|
||||
|
||||
type btfHandleCache map[*btf.Spec]*btf.Handle
|
||||
type handleCache struct {
|
||||
btfHandles map[*btf.Spec]*btf.Handle
|
||||
}
|
||||
|
||||
func (btfs btfHandleCache) load(spec *btf.Spec) (*btf.Handle, error) {
|
||||
if btfs[spec] != nil {
|
||||
return btfs[spec], nil
|
||||
func newHandleCache() *handleCache {
|
||||
return &handleCache{
|
||||
btfHandles: make(map[*btf.Spec]*btf.Handle),
|
||||
}
|
||||
}
|
||||
|
||||
func (hc handleCache) btfHandle(spec *btf.Spec) (*btf.Handle, error) {
|
||||
if hc.btfHandles[spec] != nil {
|
||||
return hc.btfHandles[spec], nil
|
||||
}
|
||||
|
||||
handle, err := btf.NewHandle(spec)
|
||||
|
@ -281,122 +406,202 @@ func (btfs btfHandleCache) load(spec *btf.Spec) (*btf.Handle, error) {
|
|||
return nil, err
|
||||
}
|
||||
|
||||
btfs[spec] = handle
|
||||
hc.btfHandles[spec] = handle
|
||||
return handle, nil
|
||||
}
|
||||
|
||||
func (btfs btfHandleCache) close() {
|
||||
for _, handle := range btfs {
|
||||
func (hc handleCache) close() {
|
||||
for _, handle := range hc.btfHandles {
|
||||
handle.Close()
|
||||
}
|
||||
}
|
||||
|
||||
func lazyLoadCollection(coll *CollectionSpec, opts *CollectionOptions) (
|
||||
loadMap func(string) (*Map, error),
|
||||
loadProgram func(string) (*Program, error),
|
||||
done func() (map[string]*Map, map[string]*Program),
|
||||
cleanup func(),
|
||||
) {
|
||||
var (
|
||||
maps = make(map[string]*Map)
|
||||
progs = make(map[string]*Program)
|
||||
btfs = make(btfHandleCache)
|
||||
skipMapsAndProgs = false
|
||||
)
|
||||
|
||||
cleanup = func() {
|
||||
btfs.close()
|
||||
|
||||
if skipMapsAndProgs {
|
||||
return
|
||||
type collectionLoader struct {
|
||||
coll *CollectionSpec
|
||||
opts *CollectionOptions
|
||||
maps map[string]*Map
|
||||
programs map[string]*Program
|
||||
handles *handleCache
|
||||
}
|
||||
|
||||
for _, m := range maps {
|
||||
func newCollectionLoader(coll *CollectionSpec, opts *CollectionOptions) (*collectionLoader, error) {
|
||||
if opts == nil {
|
||||
opts = &CollectionOptions{}
|
||||
}
|
||||
|
||||
// Check for existing MapSpecs in the CollectionSpec for all provided replacement maps.
|
||||
for name, m := range opts.MapReplacements {
|
||||
spec, ok := coll.Maps[name]
|
||||
if !ok {
|
||||
return nil, fmt.Errorf("replacement map %s not found in CollectionSpec", name)
|
||||
}
|
||||
|
||||
if err := spec.checkCompatibility(m); err != nil {
|
||||
return nil, fmt.Errorf("using replacement map %s: %w", spec.Name, err)
|
||||
}
|
||||
}
|
||||
|
||||
return &collectionLoader{
|
||||
coll,
|
||||
opts,
|
||||
make(map[string]*Map),
|
||||
make(map[string]*Program),
|
||||
newHandleCache(),
|
||||
}, nil
|
||||
}
|
||||
|
||||
// close all resources left over in the collectionLoader.
|
||||
func (cl *collectionLoader) close() {
|
||||
cl.handles.close()
|
||||
for _, m := range cl.maps {
|
||||
m.Close()
|
||||
}
|
||||
|
||||
for _, p := range progs {
|
||||
for _, p := range cl.programs {
|
||||
p.Close()
|
||||
}
|
||||
}
|
||||
|
||||
done = func() (map[string]*Map, map[string]*Program) {
|
||||
skipMapsAndProgs = true
|
||||
return maps, progs
|
||||
}
|
||||
|
||||
loadMap = func(mapName string) (*Map, error) {
|
||||
if m := maps[mapName]; m != nil {
|
||||
func (cl *collectionLoader) loadMap(mapName string) (*Map, error) {
|
||||
if m := cl.maps[mapName]; m != nil {
|
||||
return m, nil
|
||||
}
|
||||
|
||||
mapSpec := coll.Maps[mapName]
|
||||
mapSpec := cl.coll.Maps[mapName]
|
||||
if mapSpec == nil {
|
||||
return nil, fmt.Errorf("missing map %s", mapName)
|
||||
}
|
||||
|
||||
m, err := newMapWithOptions(mapSpec, opts.Maps, btfs)
|
||||
if mapSpec.BTF != nil && cl.coll.Types != mapSpec.BTF {
|
||||
return nil, fmt.Errorf("map %s: BTF doesn't match collection", mapName)
|
||||
}
|
||||
|
||||
if replaceMap, ok := cl.opts.MapReplacements[mapName]; ok {
|
||||
// Clone the map to avoid closing user's map later on.
|
||||
m, err := replaceMap.Clone()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
cl.maps[mapName] = m
|
||||
return m, nil
|
||||
}
|
||||
|
||||
m, err := newMapWithOptions(mapSpec, cl.opts.Maps, cl.handles)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("map %s: %w", mapName, err)
|
||||
}
|
||||
|
||||
maps[mapName] = m
|
||||
cl.maps[mapName] = m
|
||||
return m, nil
|
||||
}
|
||||
|
||||
loadProgram = func(progName string) (*Program, error) {
|
||||
if prog := progs[progName]; prog != nil {
|
||||
func (cl *collectionLoader) loadProgram(progName string) (*Program, error) {
|
||||
if prog := cl.programs[progName]; prog != nil {
|
||||
return prog, nil
|
||||
}
|
||||
|
||||
progSpec := coll.Programs[progName]
|
||||
progSpec := cl.coll.Programs[progName]
|
||||
if progSpec == nil {
|
||||
return nil, fmt.Errorf("unknown program %s", progName)
|
||||
}
|
||||
|
||||
// Bail out early if we know the kernel is going to reject the program.
|
||||
// This skips loading map dependencies, saving some cleanup work later.
|
||||
if progSpec.Type == UnspecifiedProgram {
|
||||
return nil, fmt.Errorf("cannot load program %s: program type is unspecified", progName)
|
||||
}
|
||||
|
||||
if progSpec.BTF != nil && cl.coll.Types != progSpec.BTF {
|
||||
return nil, fmt.Errorf("program %s: BTF doesn't match collection", progName)
|
||||
}
|
||||
|
||||
progSpec = progSpec.Copy()
|
||||
|
||||
// Rewrite any reference to a valid map.
|
||||
// Rewrite any reference to a valid map in the program's instructions,
|
||||
// which includes all of its dependencies.
|
||||
for i := range progSpec.Instructions {
|
||||
ins := &progSpec.Instructions[i]
|
||||
|
||||
if ins.OpCode != asm.LoadImmOp(asm.DWord) || ins.Reference == "" {
|
||||
if !ins.IsLoadFromMap() || ins.Reference() == "" {
|
||||
continue
|
||||
}
|
||||
|
||||
if uint32(ins.Constant) != math.MaxUint32 {
|
||||
// Don't overwrite maps already rewritten, users can
|
||||
// rewrite programs in the spec themselves
|
||||
// Don't overwrite map loads containing non-zero map fd's,
|
||||
// they can be manually included by the caller.
|
||||
// Map FDs/IDs are placed in the lower 32 bits of Constant.
|
||||
if int32(ins.Constant) > 0 {
|
||||
continue
|
||||
}
|
||||
|
||||
m, err := loadMap(ins.Reference)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("program %s: %s", progName, err)
|
||||
}
|
||||
|
||||
fd := m.FD()
|
||||
if fd < 0 {
|
||||
return nil, fmt.Errorf("map %s: %w", ins.Reference, internal.ErrClosedFd)
|
||||
}
|
||||
if err := ins.RewriteMapPtr(m.FD()); err != nil {
|
||||
return nil, fmt.Errorf("progam %s: map %s: %w", progName, ins.Reference, err)
|
||||
}
|
||||
}
|
||||
|
||||
prog, err := newProgramWithOptions(progSpec, opts.Programs, btfs)
|
||||
m, err := cl.loadMap(ins.Reference())
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("program %s: %w", progName, err)
|
||||
}
|
||||
|
||||
progs[progName] = prog
|
||||
if err := ins.AssociateMap(m); err != nil {
|
||||
return nil, fmt.Errorf("program %s: map %s: %w", progName, ins.Reference(), err)
|
||||
}
|
||||
}
|
||||
|
||||
prog, err := newProgramWithOptions(progSpec, cl.opts.Programs, cl.handles)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("program %s: %w", progName, err)
|
||||
}
|
||||
|
||||
cl.programs[progName] = prog
|
||||
return prog, nil
|
||||
}
|
||||
|
||||
return
|
||||
func (cl *collectionLoader) populateMaps() error {
|
||||
for mapName, m := range cl.maps {
|
||||
mapSpec, ok := cl.coll.Maps[mapName]
|
||||
if !ok {
|
||||
return fmt.Errorf("missing map spec %s", mapName)
|
||||
}
|
||||
|
||||
// LoadCollection parses an object file and converts it to a collection.
|
||||
mapSpec = mapSpec.Copy()
|
||||
|
||||
// MapSpecs that refer to inner maps or programs within the same
|
||||
// CollectionSpec do so using strings. These strings are used as the key
|
||||
// to look up the respective object in the Maps or Programs fields.
|
||||
// Resolve those references to actual Map or Program resources that
|
||||
// have been loaded into the kernel.
|
||||
for i, kv := range mapSpec.Contents {
|
||||
if objName, ok := kv.Value.(string); ok {
|
||||
switch mapSpec.Type {
|
||||
case ProgramArray:
|
||||
// loadProgram is idempotent and could return an existing Program.
|
||||
prog, err := cl.loadProgram(objName)
|
||||
if err != nil {
|
||||
return fmt.Errorf("loading program %s, for map %s: %w", objName, mapName, err)
|
||||
}
|
||||
mapSpec.Contents[i] = MapKV{kv.Key, prog}
|
||||
|
||||
case ArrayOfMaps, HashOfMaps:
|
||||
// loadMap is idempotent and could return an existing Map.
|
||||
innerMap, err := cl.loadMap(objName)
|
||||
if err != nil {
|
||||
return fmt.Errorf("loading inner map %s, for map %s: %w", objName, mapName, err)
|
||||
}
|
||||
mapSpec.Contents[i] = MapKV{kv.Key, innerMap}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Populate and freeze the map if specified.
|
||||
if err := m.finalize(mapSpec); err != nil {
|
||||
return fmt.Errorf("populating map %s: %w", mapName, err)
|
||||
}
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// LoadCollection reads an object file and creates and loads its declared
|
||||
// resources into the kernel.
|
||||
//
|
||||
// Omitting Collection.Close() during application shutdown is an error.
|
||||
// See the package documentation for details around Map and Program lifecycle.
|
||||
func LoadCollection(file string) (*Collection, error) {
|
||||
spec, err := LoadCollectionSpec(file)
|
||||
if err != nil {
|
||||
|
@ -439,81 +644,42 @@ func (coll *Collection) DetachProgram(name string) *Program {
|
|||
return p
|
||||
}
|
||||
|
||||
// Assign the contents of a collection to a struct.
|
||||
//
|
||||
// Deprecated: use CollectionSpec.Assign instead. It provides the same
|
||||
// functionality but creates only the maps and programs requested.
|
||||
func (coll *Collection) Assign(to interface{}) error {
|
||||
assignedMaps := make(map[string]struct{})
|
||||
assignedPrograms := make(map[string]struct{})
|
||||
valueOf := func(typ reflect.Type, name string) (reflect.Value, error) {
|
||||
switch typ {
|
||||
case reflect.TypeOf((*Program)(nil)):
|
||||
p := coll.Programs[name]
|
||||
if p == nil {
|
||||
return reflect.Value{}, fmt.Errorf("missing program %q", name)
|
||||
}
|
||||
assignedPrograms[name] = struct{}{}
|
||||
return reflect.ValueOf(p), nil
|
||||
case reflect.TypeOf((*Map)(nil)):
|
||||
m := coll.Maps[name]
|
||||
if m == nil {
|
||||
return reflect.Value{}, fmt.Errorf("missing map %q", name)
|
||||
}
|
||||
assignedMaps[name] = struct{}{}
|
||||
return reflect.ValueOf(m), nil
|
||||
default:
|
||||
return reflect.Value{}, fmt.Errorf("unsupported type %s", typ)
|
||||
}
|
||||
}
|
||||
|
||||
if err := assignValues(to, valueOf); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
for name := range assignedPrograms {
|
||||
coll.DetachProgram(name)
|
||||
}
|
||||
|
||||
for name := range assignedMaps {
|
||||
coll.DetachMap(name)
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
func assignValues(to interface{}, valueOf func(reflect.Type, string) (reflect.Value, error)) error {
|
||||
// structField represents a struct field containing the ebpf struct tag.
|
||||
type structField struct {
|
||||
reflect.StructField
|
||||
value reflect.Value
|
||||
}
|
||||
|
||||
var (
|
||||
fields []structField
|
||||
visitedTypes = make(map[reflect.Type]bool)
|
||||
flattenStruct func(reflect.Value) error
|
||||
)
|
||||
// ebpfFields extracts field names tagged with 'ebpf' from a struct type.
|
||||
// Keep track of visited types to avoid infinite recursion.
|
||||
func ebpfFields(structVal reflect.Value, visited map[reflect.Type]bool) ([]structField, error) {
|
||||
if visited == nil {
|
||||
visited = make(map[reflect.Type]bool)
|
||||
}
|
||||
|
||||
flattenStruct = func(structVal reflect.Value) error {
|
||||
structType := structVal.Type()
|
||||
if structType.Kind() != reflect.Struct {
|
||||
return fmt.Errorf("%s is not a struct", structType)
|
||||
return nil, fmt.Errorf("%s is not a struct", structType)
|
||||
}
|
||||
|
||||
if visitedTypes[structType] {
|
||||
return fmt.Errorf("recursion on type %s", structType)
|
||||
if visited[structType] {
|
||||
return nil, fmt.Errorf("recursion on type %s", structType)
|
||||
}
|
||||
|
||||
fields := make([]structField, 0, structType.NumField())
|
||||
for i := 0; i < structType.NumField(); i++ {
|
||||
field := structField{structType.Field(i), structVal.Field(i)}
|
||||
|
||||
// If the field is tagged, gather it and move on.
|
||||
name := field.Tag.Get("ebpf")
|
||||
if name != "" {
|
||||
fields = append(fields, field)
|
||||
continue
|
||||
}
|
||||
|
||||
var err error
|
||||
// If the field does not have an ebpf tag, but is a struct or a pointer
|
||||
// to a struct, attempt to gather its fields as well.
|
||||
var v reflect.Value
|
||||
switch field.Type.Kind() {
|
||||
case reflect.Ptr:
|
||||
if field.Type.Elem().Kind() != reflect.Struct {
|
||||
|
@ -521,26 +687,38 @@ func assignValues(to interface{}, valueOf func(reflect.Type, string) (reflect.Va
|
|||
}
|
||||
|
||||
if field.value.IsNil() {
|
||||
return fmt.Errorf("nil pointer to %s", structType)
|
||||
return nil, fmt.Errorf("nil pointer to %s", structType)
|
||||
}
|
||||
|
||||
err = flattenStruct(field.value.Elem())
|
||||
// Obtain the destination type of the pointer.
|
||||
v = field.value.Elem()
|
||||
|
||||
case reflect.Struct:
|
||||
err = flattenStruct(field.value)
|
||||
// Reference the value's type directly.
|
||||
v = field.value
|
||||
|
||||
default:
|
||||
continue
|
||||
}
|
||||
|
||||
inner, err := ebpfFields(v, visited)
|
||||
if err != nil {
|
||||
return fmt.Errorf("field %s: %s", field.Name, err)
|
||||
}
|
||||
return nil, fmt.Errorf("field %s: %w", field.Name, err)
|
||||
}
|
||||
|
||||
return nil
|
||||
fields = append(fields, inner...)
|
||||
}
|
||||
|
||||
return fields, nil
|
||||
}
|
||||
|
||||
// assignValues attempts to populate all fields of 'to' tagged with 'ebpf'.
|
||||
//
|
||||
// getValue is called for every tagged field of 'to' and must return the value
|
||||
// to be assigned to the field with the given typ and name.
|
||||
func assignValues(to interface{},
|
||||
getValue func(typ reflect.Type, name string) (interface{}, error)) error {
|
||||
|
||||
toValue := reflect.ValueOf(to)
|
||||
if toValue.Type().Kind() != reflect.Ptr {
|
||||
return fmt.Errorf("%T is not a pointer to struct", to)
|
||||
|
@ -550,7 +728,8 @@ func assignValues(to interface{}, valueOf func(reflect.Type, string) (reflect.Va
|
|||
return fmt.Errorf("nil pointer to %T", to)
|
||||
}
|
||||
|
||||
if err := flattenStruct(toValue.Elem()); err != nil {
|
||||
fields, err := ebpfFields(toValue.Elem(), nil)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
|
@ -560,19 +739,23 @@ func assignValues(to interface{}, valueOf func(reflect.Type, string) (reflect.Va
|
|||
name string
|
||||
}
|
||||
|
||||
assignedTo := make(map[elem]string)
|
||||
assigned := make(map[elem]string)
|
||||
for _, field := range fields {
|
||||
name := field.Tag.Get("ebpf")
|
||||
if strings.Contains(name, ",") {
|
||||
// Get string value the field is tagged with.
|
||||
tag := field.Tag.Get("ebpf")
|
||||
if strings.Contains(tag, ",") {
|
||||
return fmt.Errorf("field %s: ebpf tag contains a comma", field.Name)
|
||||
}
|
||||
|
||||
e := elem{field.Type, name}
|
||||
if assignedField := assignedTo[e]; assignedField != "" {
|
||||
return fmt.Errorf("field %s: %q was already assigned to %s", field.Name, name, assignedField)
|
||||
// Check if the eBPF object with the requested
|
||||
// type and tag was already assigned elsewhere.
|
||||
e := elem{field.Type, tag}
|
||||
if af := assigned[e]; af != "" {
|
||||
return fmt.Errorf("field %s: object %q was already assigned to %s", field.Name, tag, af)
|
||||
}
|
||||
|
||||
value, err := valueOf(field.Type, name)
|
||||
// Get the eBPF object referred to by the tag.
|
||||
value, err := getValue(field.Type, tag)
|
||||
if err != nil {
|
||||
return fmt.Errorf("field %s: %w", field.Name, err)
|
||||
}
|
||||
|
@ -580,9 +763,9 @@ func assignValues(to interface{}, valueOf func(reflect.Type, string) (reflect.Va
|
|||
if !field.value.CanSet() {
|
||||
return fmt.Errorf("field %s: can't set value", field.Name)
|
||||
}
|
||||
field.value.Set(reflect.ValueOf(value))
|
||||
|
||||
field.value.Set(value)
|
||||
assignedTo[e] = field.Name
|
||||
assigned[e] = field.Name
|
||||
}
|
||||
|
||||
return nil
|
||||
|
|
|
@ -13,4 +13,13 @@
|
|||
// your application as any other resource.
|
||||
//
|
||||
// Use the link subpackage to attach a loaded program to a hook in the kernel.
|
||||
//
|
||||
// Note that losing all references to Map and Program resources will cause
|
||||
// their underlying file descriptors to be closed, potentially removing those
|
||||
// objects from the kernel. Always retain a reference by e.g. deferring a
|
||||
// Close() of a Collection or LoadAndAssign object until application exit.
|
||||
//
|
||||
// Special care needs to be taken when handling maps of type ProgramArray,
|
||||
// as the kernel erases its contents when the last userspace or bpffs
|
||||
// reference disappears, regardless of the map being in active use.
|
||||
package ebpf
|
||||
|
|
File diff suppressed because it is too large
Load Diff
|
@ -1,21 +0,0 @@
|
|||
// +build gofuzz
|
||||
|
||||
// Use with https://github.com/dvyukov/go-fuzz
|
||||
|
||||
package ebpf
|
||||
|
||||
import "bytes"
|
||||
|
||||
func FuzzLoadCollectionSpec(data []byte) int {
|
||||
spec, err := LoadCollectionSpecFromReader(bytes.NewReader(data))
|
||||
if err != nil {
|
||||
if spec != nil {
|
||||
panic("spec is not nil")
|
||||
}
|
||||
return 0
|
||||
}
|
||||
if spec == nil {
|
||||
panic("spec is nil")
|
||||
}
|
||||
return 1
|
||||
}
|
|
@ -2,6 +2,7 @@ package ebpf
|
|||
|
||||
import (
|
||||
"bufio"
|
||||
"bytes"
|
||||
"encoding/hex"
|
||||
"errors"
|
||||
"fmt"
|
||||
|
@ -10,8 +11,13 @@ import (
|
|||
"strings"
|
||||
"syscall"
|
||||
"time"
|
||||
"unsafe"
|
||||
|
||||
"github.com/cilium/ebpf/asm"
|
||||
"github.com/cilium/ebpf/btf"
|
||||
"github.com/cilium/ebpf/internal"
|
||||
"github.com/cilium/ebpf/internal/sys"
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
// MapInfo describes a map.
|
||||
|
@ -22,12 +28,13 @@ type MapInfo struct {
|
|||
ValueSize uint32
|
||||
MaxEntries uint32
|
||||
Flags uint32
|
||||
// Name as supplied by user space at load time.
|
||||
// Name as supplied by user space at load time. Available from 4.15.
|
||||
Name string
|
||||
}
|
||||
|
||||
func newMapInfoFromFd(fd *internal.FD) (*MapInfo, error) {
|
||||
info, err := bpfGetMapInfoByFD(fd)
|
||||
func newMapInfoFromFd(fd *sys.FD) (*MapInfo, error) {
|
||||
var info sys.MapInfo
|
||||
err := sys.ObjInfo(fd, &info)
|
||||
if errors.Is(err, syscall.EINVAL) {
|
||||
return newMapInfoFromProc(fd)
|
||||
}
|
||||
|
@ -36,18 +43,17 @@ func newMapInfoFromFd(fd *internal.FD) (*MapInfo, error) {
|
|||
}
|
||||
|
||||
return &MapInfo{
|
||||
MapType(info.map_type),
|
||||
MapID(info.id),
|
||||
info.key_size,
|
||||
info.value_size,
|
||||
info.max_entries,
|
||||
info.map_flags,
|
||||
// name is available from 4.15.
|
||||
internal.CString(info.name[:]),
|
||||
MapType(info.Type),
|
||||
MapID(info.Id),
|
||||
info.KeySize,
|
||||
info.ValueSize,
|
||||
info.MaxEntries,
|
||||
info.MapFlags,
|
||||
unix.ByteSliceToString(info.Name[:]),
|
||||
}, nil
|
||||
}
|
||||
|
||||
func newMapInfoFromProc(fd *internal.FD) (*MapInfo, error) {
|
||||
func newMapInfoFromProc(fd *sys.FD) (*MapInfo, error) {
|
||||
var mi MapInfo
|
||||
err := scanFdInfo(fd, map[string]interface{}{
|
||||
"map_type": &mi.Type,
|
||||
|
@ -83,16 +89,21 @@ type programStats struct {
|
|||
type ProgramInfo struct {
|
||||
Type ProgramType
|
||||
id ProgramID
|
||||
// Truncated hash of the BPF bytecode.
|
||||
// Truncated hash of the BPF bytecode. Available from 4.13.
|
||||
Tag string
|
||||
// Name as supplied by user space at load time.
|
||||
// Name as supplied by user space at load time. Available from 4.15.
|
||||
Name string
|
||||
|
||||
btf btf.ID
|
||||
stats *programStats
|
||||
|
||||
maps []MapID
|
||||
insns []byte
|
||||
}
|
||||
|
||||
func newProgramInfoFromFd(fd *internal.FD) (*ProgramInfo, error) {
|
||||
info, err := bpfGetProgInfoByFD(fd)
|
||||
func newProgramInfoFromFd(fd *sys.FD) (*ProgramInfo, error) {
|
||||
var info sys.ProgInfo
|
||||
err := sys.ObjInfo(fd, &info)
|
||||
if errors.Is(err, syscall.EINVAL) {
|
||||
return newProgramInfoFromProc(fd)
|
||||
}
|
||||
|
@ -100,21 +111,43 @@ func newProgramInfoFromFd(fd *internal.FD) (*ProgramInfo, error) {
|
|||
return nil, err
|
||||
}
|
||||
|
||||
return &ProgramInfo{
|
||||
Type: ProgramType(info.prog_type),
|
||||
id: ProgramID(info.id),
|
||||
// tag is available if the kernel supports BPF_PROG_GET_INFO_BY_FD.
|
||||
Tag: hex.EncodeToString(info.tag[:]),
|
||||
// name is available from 4.15.
|
||||
Name: internal.CString(info.name[:]),
|
||||
pi := ProgramInfo{
|
||||
Type: ProgramType(info.Type),
|
||||
id: ProgramID(info.Id),
|
||||
Tag: hex.EncodeToString(info.Tag[:]),
|
||||
Name: unix.ByteSliceToString(info.Name[:]),
|
||||
btf: btf.ID(info.BtfId),
|
||||
stats: &programStats{
|
||||
runtime: time.Duration(info.run_time_ns),
|
||||
runCount: info.run_cnt,
|
||||
runtime: time.Duration(info.RunTimeNs),
|
||||
runCount: info.RunCnt,
|
||||
},
|
||||
}, nil
|
||||
}
|
||||
|
||||
func newProgramInfoFromProc(fd *internal.FD) (*ProgramInfo, error) {
|
||||
// Start with a clean struct for the second call, otherwise we may get EFAULT.
|
||||
var info2 sys.ProgInfo
|
||||
|
||||
if info.NrMapIds > 0 {
|
||||
pi.maps = make([]MapID, info.NrMapIds)
|
||||
info2.NrMapIds = info.NrMapIds
|
||||
info2.MapIds = sys.NewPointer(unsafe.Pointer(&pi.maps[0]))
|
||||
}
|
||||
|
||||
if info.XlatedProgLen > 0 {
|
||||
pi.insns = make([]byte, info.XlatedProgLen)
|
||||
info2.XlatedProgLen = info.XlatedProgLen
|
||||
info2.XlatedProgInsns = sys.NewSlicePointer(pi.insns)
|
||||
}
|
||||
|
||||
if info.NrMapIds > 0 || info.XlatedProgLen > 0 {
|
||||
if err := sys.ObjInfo(fd, &info2); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
}
|
||||
|
||||
return &pi, nil
|
||||
}
|
||||
|
||||
func newProgramInfoFromProc(fd *sys.FD) (*ProgramInfo, error) {
|
||||
var info ProgramInfo
|
||||
err := scanFdInfo(fd, map[string]interface{}{
|
||||
"prog_type": &info.Type,
|
||||
|
@ -142,6 +175,18 @@ func (pi *ProgramInfo) ID() (ProgramID, bool) {
|
|||
return pi.id, pi.id > 0
|
||||
}
|
||||
|
||||
// BTFID returns the BTF ID associated with the program.
|
||||
//
|
||||
// The ID is only valid as long as the associated program is kept alive.
|
||||
// Available from 5.0.
|
||||
//
|
||||
// The bool return value indicates whether this optional field is available and
|
||||
// populated. (The field may be available but not populated if the kernel
|
||||
// supports the field but the program was loaded without BTF information.)
|
||||
func (pi *ProgramInfo) BTFID() (btf.ID, bool) {
|
||||
return pi.btf, pi.btf > 0
|
||||
}
|
||||
|
||||
// RunCount returns the total number of times the program was called.
|
||||
//
|
||||
// Can return 0 if the collection of statistics is not enabled. See EnableStats().
|
||||
|
@ -164,13 +209,50 @@ func (pi *ProgramInfo) Runtime() (time.Duration, bool) {
|
|||
return time.Duration(0), false
|
||||
}
|
||||
|
||||
func scanFdInfo(fd *internal.FD, fields map[string]interface{}) error {
|
||||
raw, err := fd.Value()
|
||||
if err != nil {
|
||||
return err
|
||||
// Instructions returns the 'xlated' instruction stream of the program
|
||||
// after it has been verified and rewritten by the kernel. These instructions
|
||||
// cannot be loaded back into the kernel as-is, this is mainly used for
|
||||
// inspecting loaded programs for troubleshooting, dumping, etc.
|
||||
//
|
||||
// For example, map accesses are made to reference their kernel map IDs,
|
||||
// not the FDs they had when the program was inserted. Note that before
|
||||
// the introduction of bpf_insn_prepare_dump in kernel 4.16, xlated
|
||||
// instructions were not sanitized, making the output even less reusable
|
||||
// and less likely to round-trip or evaluate to the same program Tag.
|
||||
//
|
||||
// The first instruction is marked as a symbol using the Program's name.
|
||||
//
|
||||
// Available from 4.13. Requires CAP_BPF or equivalent.
|
||||
func (pi *ProgramInfo) Instructions() (asm.Instructions, error) {
|
||||
// If the calling process is not BPF-capable or if the kernel doesn't
|
||||
// support getting xlated instructions, the field will be zero.
|
||||
if len(pi.insns) == 0 {
|
||||
return nil, fmt.Errorf("insufficient permissions or unsupported kernel: %w", ErrNotSupported)
|
||||
}
|
||||
|
||||
fh, err := os.Open(fmt.Sprintf("/proc/self/fdinfo/%d", raw))
|
||||
r := bytes.NewReader(pi.insns)
|
||||
var insns asm.Instructions
|
||||
if err := insns.Unmarshal(r, internal.NativeEndian); err != nil {
|
||||
return nil, fmt.Errorf("unmarshaling instructions: %w", err)
|
||||
}
|
||||
|
||||
// Tag the first instruction with the name of the program, if available.
|
||||
insns[0] = insns[0].WithSymbol(pi.Name)
|
||||
|
||||
return insns, nil
|
||||
}
|
||||
|
||||
// MapIDs returns the maps related to the program.
|
||||
//
|
||||
// Available from 4.15.
|
||||
//
|
||||
// The bool return value indicates whether this optional field is available.
|
||||
func (pi *ProgramInfo) MapIDs() ([]MapID, bool) {
|
||||
return pi.maps, pi.maps != nil
|
||||
}
|
||||
|
||||
func scanFdInfo(fd *sys.FD, fields map[string]interface{}) error {
|
||||
fh, err := os.Open(fmt.Sprintf("/proc/self/fdinfo/%d", fd.Int()))
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
@ -213,6 +295,10 @@ func scanFdInfoReader(r io.Reader, fields map[string]interface{}) error {
|
|||
return err
|
||||
}
|
||||
|
||||
if len(fields) > 0 && scanned == 0 {
|
||||
return ErrNotSupported
|
||||
}
|
||||
|
||||
if scanned != len(fields) {
|
||||
return errMissingFields
|
||||
}
|
||||
|
@ -227,11 +313,9 @@ func scanFdInfoReader(r io.Reader, fields map[string]interface{}) error {
|
|||
//
|
||||
// Requires at least 5.8.
|
||||
func EnableStats(which uint32) (io.Closer, error) {
|
||||
attr := internal.BPFEnableStatsAttr{
|
||||
StatsType: which,
|
||||
}
|
||||
|
||||
fd, err := internal.BPFEnableStats(&attr)
|
||||
fd, err := sys.EnableStats(&sys.EnableStatsAttr{
|
||||
Type: which,
|
||||
})
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
|
|
@ -0,0 +1,6 @@
|
|||
package internal
|
||||
|
||||
// Align returns 'n' updated to 'alignment' boundary.
|
||||
func Align(n, alignment int) int {
|
||||
return (int(n) + alignment - 1) / alignment * alignment
|
||||
}
|
|
@ -1,791 +0,0 @@
|
|||
package btf
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"debug/elf"
|
||||
"encoding/binary"
|
||||
"errors"
|
||||
"fmt"
|
||||
"io"
|
||||
"io/ioutil"
|
||||
"math"
|
||||
"os"
|
||||
"reflect"
|
||||
"sync"
|
||||
"unsafe"
|
||||
|
||||
"github.com/cilium/ebpf/internal"
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
const btfMagic = 0xeB9F
|
||||
|
||||
// Errors returned by BTF functions.
|
||||
var (
|
||||
ErrNotSupported = internal.ErrNotSupported
|
||||
ErrNotFound = errors.New("not found")
|
||||
ErrNoExtendedInfo = errors.New("no extended info")
|
||||
)
|
||||
|
||||
// Spec represents decoded BTF.
|
||||
type Spec struct {
|
||||
rawTypes []rawType
|
||||
strings stringTable
|
||||
types []Type
|
||||
namedTypes map[string][]namedType
|
||||
funcInfos map[string]extInfo
|
||||
lineInfos map[string]extInfo
|
||||
coreRelos map[string]bpfCoreRelos
|
||||
byteOrder binary.ByteOrder
|
||||
}
|
||||
|
||||
type btfHeader struct {
|
||||
Magic uint16
|
||||
Version uint8
|
||||
Flags uint8
|
||||
HdrLen uint32
|
||||
|
||||
TypeOff uint32
|
||||
TypeLen uint32
|
||||
StringOff uint32
|
||||
StringLen uint32
|
||||
}
|
||||
|
||||
// LoadSpecFromReader reads BTF sections from an ELF.
|
||||
//
|
||||
// Returns a nil Spec and no error if no BTF was present.
|
||||
func LoadSpecFromReader(rd io.ReaderAt) (*Spec, error) {
|
||||
file, err := internal.NewSafeELFFile(rd)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
defer file.Close()
|
||||
|
||||
btfSection, btfExtSection, sectionSizes, err := findBtfSections(file)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
if btfSection == nil {
|
||||
return nil, nil
|
||||
}
|
||||
|
||||
symbols, err := file.Symbols()
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("can't read symbols: %v", err)
|
||||
}
|
||||
|
||||
variableOffsets := make(map[variable]uint32)
|
||||
for _, symbol := range symbols {
|
||||
if idx := symbol.Section; idx >= elf.SHN_LORESERVE && idx <= elf.SHN_HIRESERVE {
|
||||
// Ignore things like SHN_ABS
|
||||
continue
|
||||
}
|
||||
|
||||
if int(symbol.Section) >= len(file.Sections) {
|
||||
return nil, fmt.Errorf("symbol %s: invalid section %d", symbol.Name, symbol.Section)
|
||||
}
|
||||
|
||||
secName := file.Sections[symbol.Section].Name
|
||||
if _, ok := sectionSizes[secName]; !ok {
|
||||
continue
|
||||
}
|
||||
|
||||
if symbol.Value > math.MaxUint32 {
|
||||
return nil, fmt.Errorf("section %s: symbol %s: size exceeds maximum", secName, symbol.Name)
|
||||
}
|
||||
|
||||
variableOffsets[variable{secName, symbol.Name}] = uint32(symbol.Value)
|
||||
}
|
||||
|
||||
spec, err := loadNakedSpec(btfSection.Open(), file.ByteOrder, sectionSizes, variableOffsets)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
if btfExtSection == nil {
|
||||
return spec, nil
|
||||
}
|
||||
|
||||
spec.funcInfos, spec.lineInfos, spec.coreRelos, err = parseExtInfos(btfExtSection.Open(), file.ByteOrder, spec.strings)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("can't read ext info: %w", err)
|
||||
}
|
||||
|
||||
return spec, nil
|
||||
}
|
||||
|
||||
func findBtfSections(file *internal.SafeELFFile) (*elf.Section, *elf.Section, map[string]uint32, error) {
|
||||
var (
|
||||
btfSection *elf.Section
|
||||
btfExtSection *elf.Section
|
||||
sectionSizes = make(map[string]uint32)
|
||||
)
|
||||
|
||||
for _, sec := range file.Sections {
|
||||
switch sec.Name {
|
||||
case ".BTF":
|
||||
btfSection = sec
|
||||
case ".BTF.ext":
|
||||
btfExtSection = sec
|
||||
default:
|
||||
if sec.Type != elf.SHT_PROGBITS && sec.Type != elf.SHT_NOBITS {
|
||||
break
|
||||
}
|
||||
|
||||
if sec.Size > math.MaxUint32 {
|
||||
return nil, nil, nil, fmt.Errorf("section %s exceeds maximum size", sec.Name)
|
||||
}
|
||||
|
||||
sectionSizes[sec.Name] = uint32(sec.Size)
|
||||
}
|
||||
}
|
||||
return btfSection, btfExtSection, sectionSizes, nil
|
||||
}
|
||||
|
||||
func loadSpecFromVmlinux(rd io.ReaderAt) (*Spec, error) {
|
||||
file, err := internal.NewSafeELFFile(rd)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
defer file.Close()
|
||||
|
||||
btfSection, _, _, err := findBtfSections(file)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf(".BTF ELF section: %s", err)
|
||||
}
|
||||
if btfSection == nil {
|
||||
return nil, fmt.Errorf("unable to find .BTF ELF section")
|
||||
}
|
||||
return loadNakedSpec(btfSection.Open(), file.ByteOrder, nil, nil)
|
||||
}
|
||||
|
||||
func loadNakedSpec(btf io.ReadSeeker, bo binary.ByteOrder, sectionSizes map[string]uint32, variableOffsets map[variable]uint32) (*Spec, error) {
|
||||
rawTypes, rawStrings, err := parseBTF(btf, bo)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
err = fixupDatasec(rawTypes, rawStrings, sectionSizes, variableOffsets)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
types, typesByName, err := inflateRawTypes(rawTypes, rawStrings)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return &Spec{
|
||||
rawTypes: rawTypes,
|
||||
namedTypes: typesByName,
|
||||
types: types,
|
||||
strings: rawStrings,
|
||||
byteOrder: bo,
|
||||
}, nil
|
||||
}
|
||||
|
||||
var kernelBTF struct {
|
||||
sync.Mutex
|
||||
*Spec
|
||||
}
|
||||
|
||||
// LoadKernelSpec returns the current kernel's BTF information.
|
||||
//
|
||||
// Requires a >= 5.5 kernel with CONFIG_DEBUG_INFO_BTF enabled. Returns
|
||||
// ErrNotSupported if BTF is not enabled.
|
||||
func LoadKernelSpec() (*Spec, error) {
|
||||
kernelBTF.Lock()
|
||||
defer kernelBTF.Unlock()
|
||||
|
||||
if kernelBTF.Spec != nil {
|
||||
return kernelBTF.Spec, nil
|
||||
}
|
||||
|
||||
var err error
|
||||
kernelBTF.Spec, err = loadKernelSpec()
|
||||
return kernelBTF.Spec, err
|
||||
}
|
||||
|
||||
func loadKernelSpec() (*Spec, error) {
|
||||
release, err := unix.KernelRelease()
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("can't read kernel release number: %w", err)
|
||||
}
|
||||
|
||||
fh, err := os.Open("/sys/kernel/btf/vmlinux")
|
||||
if err == nil {
|
||||
defer fh.Close()
|
||||
|
||||
return loadNakedSpec(fh, internal.NativeEndian, nil, nil)
|
||||
}
|
||||
|
||||
// use same list of locations as libbpf
|
||||
// https://github.com/libbpf/libbpf/blob/9a3a42608dbe3731256a5682a125ac1e23bced8f/src/btf.c#L3114-L3122
|
||||
locations := []string{
|
||||
"/boot/vmlinux-%s",
|
||||
"/lib/modules/%s/vmlinux-%[1]s",
|
||||
"/lib/modules/%s/build/vmlinux",
|
||||
"/usr/lib/modules/%s/kernel/vmlinux",
|
||||
"/usr/lib/debug/boot/vmlinux-%s",
|
||||
"/usr/lib/debug/boot/vmlinux-%s.debug",
|
||||
"/usr/lib/debug/lib/modules/%s/vmlinux",
|
||||
}
|
||||
|
||||
for _, loc := range locations {
|
||||
path := fmt.Sprintf(loc, release)
|
||||
|
||||
fh, err := os.Open(path)
|
||||
if err != nil {
|
||||
continue
|
||||
}
|
||||
defer fh.Close()
|
||||
|
||||
return loadSpecFromVmlinux(fh)
|
||||
}
|
||||
|
||||
return nil, fmt.Errorf("no BTF for kernel version %s: %w", release, internal.ErrNotSupported)
|
||||
}
|
||||
|
||||
func parseBTF(btf io.ReadSeeker, bo binary.ByteOrder) ([]rawType, stringTable, error) {
|
||||
rawBTF, err := ioutil.ReadAll(btf)
|
||||
if err != nil {
|
||||
return nil, nil, fmt.Errorf("can't read BTF: %v", err)
|
||||
}
|
||||
|
||||
rd := bytes.NewReader(rawBTF)
|
||||
|
||||
var header btfHeader
|
||||
if err := binary.Read(rd, bo, &header); err != nil {
|
||||
return nil, nil, fmt.Errorf("can't read header: %v", err)
|
||||
}
|
||||
|
||||
if header.Magic != btfMagic {
|
||||
return nil, nil, fmt.Errorf("incorrect magic value %v", header.Magic)
|
||||
}
|
||||
|
||||
if header.Version != 1 {
|
||||
return nil, nil, fmt.Errorf("unexpected version %v", header.Version)
|
||||
}
|
||||
|
||||
if header.Flags != 0 {
|
||||
return nil, nil, fmt.Errorf("unsupported flags %v", header.Flags)
|
||||
}
|
||||
|
||||
remainder := int64(header.HdrLen) - int64(binary.Size(&header))
|
||||
if remainder < 0 {
|
||||
return nil, nil, errors.New("header is too short")
|
||||
}
|
||||
|
||||
if _, err := io.CopyN(internal.DiscardZeroes{}, rd, remainder); err != nil {
|
||||
return nil, nil, fmt.Errorf("header padding: %v", err)
|
||||
}
|
||||
|
||||
if _, err := rd.Seek(int64(header.HdrLen+header.StringOff), io.SeekStart); err != nil {
|
||||
return nil, nil, fmt.Errorf("can't seek to start of string section: %v", err)
|
||||
}
|
||||
|
||||
rawStrings, err := readStringTable(io.LimitReader(rd, int64(header.StringLen)))
|
||||
if err != nil {
|
||||
return nil, nil, fmt.Errorf("can't read type names: %w", err)
|
||||
}
|
||||
|
||||
if _, err := rd.Seek(int64(header.HdrLen+header.TypeOff), io.SeekStart); err != nil {
|
||||
return nil, nil, fmt.Errorf("can't seek to start of type section: %v", err)
|
||||
}
|
||||
|
||||
rawTypes, err := readTypes(io.LimitReader(rd, int64(header.TypeLen)), bo)
|
||||
if err != nil {
|
||||
return nil, nil, fmt.Errorf("can't read types: %w", err)
|
||||
}
|
||||
|
||||
return rawTypes, rawStrings, nil
|
||||
}
|
||||
|
||||
type variable struct {
|
||||
section string
|
||||
name string
|
||||
}
|
||||
|
||||
func fixupDatasec(rawTypes []rawType, rawStrings stringTable, sectionSizes map[string]uint32, variableOffsets map[variable]uint32) error {
|
||||
for i, rawType := range rawTypes {
|
||||
if rawType.Kind() != kindDatasec {
|
||||
continue
|
||||
}
|
||||
|
||||
name, err := rawStrings.Lookup(rawType.NameOff)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
if name == ".kconfig" || name == ".ksyms" {
|
||||
return fmt.Errorf("reference to %s: %w", name, ErrNotSupported)
|
||||
}
|
||||
|
||||
if rawTypes[i].SizeType != 0 {
|
||||
continue
|
||||
}
|
||||
|
||||
size, ok := sectionSizes[name]
|
||||
if !ok {
|
||||
return fmt.Errorf("data section %s: missing size", name)
|
||||
}
|
||||
|
||||
rawTypes[i].SizeType = size
|
||||
|
||||
secinfos := rawType.data.([]btfVarSecinfo)
|
||||
for j, secInfo := range secinfos {
|
||||
id := int(secInfo.Type - 1)
|
||||
if id >= len(rawTypes) {
|
||||
return fmt.Errorf("data section %s: invalid type id %d for variable %d", name, id, j)
|
||||
}
|
||||
|
||||
varName, err := rawStrings.Lookup(rawTypes[id].NameOff)
|
||||
if err != nil {
|
||||
return fmt.Errorf("data section %s: can't get name for type %d: %w", name, id, err)
|
||||
}
|
||||
|
||||
offset, ok := variableOffsets[variable{name, varName}]
|
||||
if !ok {
|
||||
return fmt.Errorf("data section %s: missing offset for variable %s", name, varName)
|
||||
}
|
||||
|
||||
secinfos[j].Offset = offset
|
||||
}
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
type marshalOpts struct {
|
||||
ByteOrder binary.ByteOrder
|
||||
StripFuncLinkage bool
|
||||
}
|
||||
|
||||
func (s *Spec) marshal(opts marshalOpts) ([]byte, error) {
|
||||
var (
|
||||
buf bytes.Buffer
|
||||
header = new(btfHeader)
|
||||
headerLen = binary.Size(header)
|
||||
)
|
||||
|
||||
// Reserve space for the header. We have to write it last since
|
||||
// we don't know the size of the type section yet.
|
||||
_, _ = buf.Write(make([]byte, headerLen))
|
||||
|
||||
// Write type section, just after the header.
|
||||
for _, raw := range s.rawTypes {
|
||||
switch {
|
||||
case opts.StripFuncLinkage && raw.Kind() == kindFunc:
|
||||
raw.SetLinkage(linkageStatic)
|
||||
}
|
||||
|
||||
if err := raw.Marshal(&buf, opts.ByteOrder); err != nil {
|
||||
return nil, fmt.Errorf("can't marshal BTF: %w", err)
|
||||
}
|
||||
}
|
||||
|
||||
typeLen := uint32(buf.Len() - headerLen)
|
||||
|
||||
// Write string section after type section.
|
||||
_, _ = buf.Write(s.strings)
|
||||
|
||||
// Fill out the header, and write it out.
|
||||
header = &btfHeader{
|
||||
Magic: btfMagic,
|
||||
Version: 1,
|
||||
Flags: 0,
|
||||
HdrLen: uint32(headerLen),
|
||||
TypeOff: 0,
|
||||
TypeLen: typeLen,
|
||||
StringOff: typeLen,
|
||||
StringLen: uint32(len(s.strings)),
|
||||
}
|
||||
|
||||
raw := buf.Bytes()
|
||||
err := binary.Write(sliceWriter(raw[:headerLen]), opts.ByteOrder, header)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("can't write header: %v", err)
|
||||
}
|
||||
|
||||
return raw, nil
|
||||
}
|
||||
|
||||
type sliceWriter []byte
|
||||
|
||||
func (sw sliceWriter) Write(p []byte) (int, error) {
|
||||
if len(p) != len(sw) {
|
||||
return 0, errors.New("size doesn't match")
|
||||
}
|
||||
|
||||
return copy(sw, p), nil
|
||||
}
|
||||
|
||||
// Program finds the BTF for a specific section.
|
||||
//
|
||||
// Length is the number of bytes in the raw BPF instruction stream.
|
||||
//
|
||||
// Returns an error which may wrap ErrNoExtendedInfo if the Spec doesn't
|
||||
// contain extended BTF info.
|
||||
func (s *Spec) Program(name string, length uint64) (*Program, error) {
|
||||
if length == 0 {
|
||||
return nil, errors.New("length musn't be zero")
|
||||
}
|
||||
|
||||
if s.funcInfos == nil && s.lineInfos == nil && s.coreRelos == nil {
|
||||
return nil, fmt.Errorf("BTF for section %s: %w", name, ErrNoExtendedInfo)
|
||||
}
|
||||
|
||||
funcInfos, funcOK := s.funcInfos[name]
|
||||
lineInfos, lineOK := s.lineInfos[name]
|
||||
coreRelos, coreOK := s.coreRelos[name]
|
||||
|
||||
if !funcOK && !lineOK && !coreOK {
|
||||
return nil, fmt.Errorf("no extended BTF info for section %s", name)
|
||||
}
|
||||
|
||||
return &Program{s, length, funcInfos, lineInfos, coreRelos}, nil
|
||||
}
|
||||
|
||||
// Datasec returns the BTF required to create maps which represent data sections.
|
||||
func (s *Spec) Datasec(name string) (*Map, error) {
|
||||
var datasec Datasec
|
||||
if err := s.FindType(name, &datasec); err != nil {
|
||||
return nil, fmt.Errorf("data section %s: can't get BTF: %w", name, err)
|
||||
}
|
||||
|
||||
m := NewMap(s, &Void{}, &datasec)
|
||||
return &m, nil
|
||||
}
|
||||
|
||||
// FindType searches for a type with a specific name.
|
||||
//
|
||||
// hint determines the type of the returned Type.
|
||||
//
|
||||
// Returns an error wrapping ErrNotFound if no matching
|
||||
// type exists in spec.
|
||||
func (s *Spec) FindType(name string, typ Type) error {
|
||||
var (
|
||||
wanted = reflect.TypeOf(typ)
|
||||
candidate Type
|
||||
)
|
||||
|
||||
for _, typ := range s.namedTypes[essentialName(name)] {
|
||||
if reflect.TypeOf(typ) != wanted {
|
||||
continue
|
||||
}
|
||||
|
||||
// Match against the full name, not just the essential one.
|
||||
if typ.name() != name {
|
||||
continue
|
||||
}
|
||||
|
||||
if candidate != nil {
|
||||
return fmt.Errorf("type %s: multiple candidates for %T", name, typ)
|
||||
}
|
||||
|
||||
candidate = typ
|
||||
}
|
||||
|
||||
if candidate == nil {
|
||||
return fmt.Errorf("type %s: %w", name, ErrNotFound)
|
||||
}
|
||||
|
||||
value := reflect.Indirect(reflect.ValueOf(copyType(candidate)))
|
||||
reflect.Indirect(reflect.ValueOf(typ)).Set(value)
|
||||
return nil
|
||||
}
|
||||
|
||||
// Handle is a reference to BTF loaded into the kernel.
|
||||
type Handle struct {
|
||||
fd *internal.FD
|
||||
}
|
||||
|
||||
// NewHandle loads BTF into the kernel.
|
||||
//
|
||||
// Returns ErrNotSupported if BTF is not supported.
|
||||
func NewHandle(spec *Spec) (*Handle, error) {
|
||||
if err := haveBTF(); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
if spec.byteOrder != internal.NativeEndian {
|
||||
return nil, fmt.Errorf("can't load %s BTF on %s", spec.byteOrder, internal.NativeEndian)
|
||||
}
|
||||
|
||||
btf, err := spec.marshal(marshalOpts{
|
||||
ByteOrder: internal.NativeEndian,
|
||||
StripFuncLinkage: haveFuncLinkage() != nil,
|
||||
})
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("can't marshal BTF: %w", err)
|
||||
}
|
||||
|
||||
if uint64(len(btf)) > math.MaxUint32 {
|
||||
return nil, errors.New("BTF exceeds the maximum size")
|
||||
}
|
||||
|
||||
attr := &bpfLoadBTFAttr{
|
||||
btf: internal.NewSlicePointer(btf),
|
||||
btfSize: uint32(len(btf)),
|
||||
}
|
||||
|
||||
fd, err := bpfLoadBTF(attr)
|
||||
if err != nil {
|
||||
logBuf := make([]byte, 64*1024)
|
||||
attr.logBuf = internal.NewSlicePointer(logBuf)
|
||||
attr.btfLogSize = uint32(len(logBuf))
|
||||
attr.btfLogLevel = 1
|
||||
_, logErr := bpfLoadBTF(attr)
|
||||
return nil, internal.ErrorWithLog(err, logBuf, logErr)
|
||||
}
|
||||
|
||||
return &Handle{fd}, nil
|
||||
}
|
||||
|
||||
// Close destroys the handle.
|
||||
//
|
||||
// Subsequent calls to FD will return an invalid value.
|
||||
func (h *Handle) Close() error {
|
||||
return h.fd.Close()
|
||||
}
|
||||
|
||||
// FD returns the file descriptor for the handle.
|
||||
func (h *Handle) FD() int {
|
||||
value, err := h.fd.Value()
|
||||
if err != nil {
|
||||
return -1
|
||||
}
|
||||
|
||||
return int(value)
|
||||
}
|
||||
|
||||
// Map is the BTF for a map.
|
||||
type Map struct {
|
||||
spec *Spec
|
||||
key, value Type
|
||||
}
|
||||
|
||||
// NewMap returns a new Map containing the given values.
|
||||
// The key and value arguments are initialized to Void if nil values are given.
|
||||
func NewMap(spec *Spec, key Type, value Type) Map {
|
||||
if key == nil {
|
||||
key = &Void{}
|
||||
}
|
||||
if value == nil {
|
||||
value = &Void{}
|
||||
}
|
||||
|
||||
return Map{
|
||||
spec: spec,
|
||||
key: key,
|
||||
value: value,
|
||||
}
|
||||
}
|
||||
|
||||
// MapSpec should be a method on Map, but is a free function
|
||||
// to hide it from users of the ebpf package.
|
||||
func MapSpec(m *Map) *Spec {
|
||||
return m.spec
|
||||
}
|
||||
|
||||
// MapKey should be a method on Map, but is a free function
|
||||
// to hide it from users of the ebpf package.
|
||||
func MapKey(m *Map) Type {
|
||||
return m.key
|
||||
}
|
||||
|
||||
// MapValue should be a method on Map, but is a free function
|
||||
// to hide it from users of the ebpf package.
|
||||
func MapValue(m *Map) Type {
|
||||
return m.value
|
||||
}
|
||||
|
||||
// Program is the BTF information for a stream of instructions.
|
||||
type Program struct {
|
||||
spec *Spec
|
||||
length uint64
|
||||
funcInfos, lineInfos extInfo
|
||||
coreRelos bpfCoreRelos
|
||||
}
|
||||
|
||||
// ProgramSpec returns the Spec needed for loading function and line infos into the kernel.
|
||||
//
|
||||
// This is a free function instead of a method to hide it from users
|
||||
// of package ebpf.
|
||||
func ProgramSpec(s *Program) *Spec {
|
||||
return s.spec
|
||||
}
|
||||
|
||||
// ProgramAppend the information from other to the Program.
|
||||
//
|
||||
// This is a free function instead of a method to hide it from users
|
||||
// of package ebpf.
|
||||
func ProgramAppend(s, other *Program) error {
|
||||
funcInfos, err := s.funcInfos.append(other.funcInfos, s.length)
|
||||
if err != nil {
|
||||
return fmt.Errorf("func infos: %w", err)
|
||||
}
|
||||
|
||||
lineInfos, err := s.lineInfos.append(other.lineInfos, s.length)
|
||||
if err != nil {
|
||||
return fmt.Errorf("line infos: %w", err)
|
||||
}
|
||||
|
||||
s.funcInfos = funcInfos
|
||||
s.lineInfos = lineInfos
|
||||
s.coreRelos = s.coreRelos.append(other.coreRelos, s.length)
|
||||
s.length += other.length
|
||||
return nil
|
||||
}
|
||||
|
||||
// ProgramFuncInfos returns the binary form of BTF function infos.
|
||||
//
|
||||
// This is a free function instead of a method to hide it from users
|
||||
// of package ebpf.
|
||||
func ProgramFuncInfos(s *Program) (recordSize uint32, bytes []byte, err error) {
|
||||
bytes, err = s.funcInfos.MarshalBinary()
|
||||
if err != nil {
|
||||
return 0, nil, err
|
||||
}
|
||||
|
||||
return s.funcInfos.recordSize, bytes, nil
|
||||
}
|
||||
|
||||
// ProgramLineInfos returns the binary form of BTF line infos.
|
||||
//
|
||||
// This is a free function instead of a method to hide it from users
|
||||
// of package ebpf.
|
||||
func ProgramLineInfos(s *Program) (recordSize uint32, bytes []byte, err error) {
|
||||
bytes, err = s.lineInfos.MarshalBinary()
|
||||
if err != nil {
|
||||
return 0, nil, err
|
||||
}
|
||||
|
||||
return s.lineInfos.recordSize, bytes, nil
|
||||
}
|
||||
|
||||
// ProgramRelocations returns the CO-RE relocations required to adjust the
|
||||
// program to the target.
|
||||
//
|
||||
// This is a free function instead of a method to hide it from users
|
||||
// of package ebpf.
|
||||
func ProgramRelocations(s *Program, target *Spec) (map[uint64]Relocation, error) {
|
||||
if len(s.coreRelos) == 0 {
|
||||
return nil, nil
|
||||
}
|
||||
|
||||
return coreRelocate(s.spec, target, s.coreRelos)
|
||||
}
|
||||
|
||||
type bpfLoadBTFAttr struct {
|
||||
btf internal.Pointer
|
||||
logBuf internal.Pointer
|
||||
btfSize uint32
|
||||
btfLogSize uint32
|
||||
btfLogLevel uint32
|
||||
}
|
||||
|
||||
func bpfLoadBTF(attr *bpfLoadBTFAttr) (*internal.FD, error) {
|
||||
fd, err := internal.BPF(internal.BPF_BTF_LOAD, unsafe.Pointer(attr), unsafe.Sizeof(*attr))
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return internal.NewFD(uint32(fd)), nil
|
||||
}
|
||||
|
||||
func marshalBTF(types interface{}, strings []byte, bo binary.ByteOrder) []byte {
|
||||
const minHeaderLength = 24
|
||||
|
||||
typesLen := uint32(binary.Size(types))
|
||||
header := btfHeader{
|
||||
Magic: btfMagic,
|
||||
Version: 1,
|
||||
HdrLen: minHeaderLength,
|
||||
TypeOff: 0,
|
||||
TypeLen: typesLen,
|
||||
StringOff: typesLen,
|
||||
StringLen: uint32(len(strings)),
|
||||
}
|
||||
|
||||
buf := new(bytes.Buffer)
|
||||
_ = binary.Write(buf, bo, &header)
|
||||
_ = binary.Write(buf, bo, types)
|
||||
buf.Write(strings)
|
||||
|
||||
return buf.Bytes()
|
||||
}
|
||||
|
||||
var haveBTF = internal.FeatureTest("BTF", "5.1", func() error {
|
||||
var (
|
||||
types struct {
|
||||
Integer btfType
|
||||
Var btfType
|
||||
btfVar struct{ Linkage uint32 }
|
||||
}
|
||||
strings = []byte{0, 'a', 0}
|
||||
)
|
||||
|
||||
// We use a BTF_KIND_VAR here, to make sure that
|
||||
// the kernel understands BTF at least as well as we
|
||||
// do. BTF_KIND_VAR was introduced ~5.1.
|
||||
types.Integer.SetKind(kindPointer)
|
||||
types.Var.NameOff = 1
|
||||
types.Var.SetKind(kindVar)
|
||||
types.Var.SizeType = 1
|
||||
|
||||
btf := marshalBTF(&types, strings, internal.NativeEndian)
|
||||
|
||||
fd, err := bpfLoadBTF(&bpfLoadBTFAttr{
|
||||
btf: internal.NewSlicePointer(btf),
|
||||
btfSize: uint32(len(btf)),
|
||||
})
|
||||
if errors.Is(err, unix.EINVAL) || errors.Is(err, unix.EPERM) {
|
||||
// Treat both EINVAL and EPERM as not supported: loading the program
|
||||
// might still succeed without BTF.
|
||||
return internal.ErrNotSupported
|
||||
}
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
fd.Close()
|
||||
return nil
|
||||
})
|
||||
|
||||
var haveFuncLinkage = internal.FeatureTest("BTF func linkage", "5.6", func() error {
|
||||
if err := haveBTF(); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
var (
|
||||
types struct {
|
||||
FuncProto btfType
|
||||
Func btfType
|
||||
}
|
||||
strings = []byte{0, 'a', 0}
|
||||
)
|
||||
|
||||
types.FuncProto.SetKind(kindFuncProto)
|
||||
types.Func.SetKind(kindFunc)
|
||||
types.Func.SizeType = 1 // aka FuncProto
|
||||
types.Func.NameOff = 1
|
||||
types.Func.SetLinkage(linkageGlobal)
|
||||
|
||||
btf := marshalBTF(&types, strings, internal.NativeEndian)
|
||||
|
||||
fd, err := bpfLoadBTF(&bpfLoadBTFAttr{
|
||||
btf: internal.NewSlicePointer(btf),
|
||||
btfSize: uint32(len(btf)),
|
||||
})
|
||||
if errors.Is(err, unix.EINVAL) {
|
||||
return internal.ErrNotSupported
|
||||
}
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
fd.Close()
|
||||
return nil
|
||||
})
|
|
@ -1,388 +0,0 @@
|
|||
package btf
|
||||
|
||||
import (
|
||||
"errors"
|
||||
"fmt"
|
||||
"reflect"
|
||||
"strconv"
|
||||
"strings"
|
||||
)
|
||||
|
||||
// Code in this file is derived from libbpf, which is available under a BSD
|
||||
// 2-Clause license.
|
||||
|
||||
// Relocation describes a CO-RE relocation.
|
||||
type Relocation struct {
|
||||
Current uint32
|
||||
New uint32
|
||||
}
|
||||
|
||||
func (r Relocation) equal(other Relocation) bool {
|
||||
return r.Current == other.Current && r.New == other.New
|
||||
}
|
||||
|
||||
// coreReloKind is the type of CO-RE relocation
|
||||
type coreReloKind uint32
|
||||
|
||||
const (
|
||||
reloFieldByteOffset coreReloKind = iota /* field byte offset */
|
||||
reloFieldByteSize /* field size in bytes */
|
||||
reloFieldExists /* field existence in target kernel */
|
||||
reloFieldSigned /* field signedness (0 - unsigned, 1 - signed) */
|
||||
reloFieldLShiftU64 /* bitfield-specific left bitshift */
|
||||
reloFieldRShiftU64 /* bitfield-specific right bitshift */
|
||||
reloTypeIDLocal /* type ID in local BPF object */
|
||||
reloTypeIDTarget /* type ID in target kernel */
|
||||
reloTypeExists /* type existence in target kernel */
|
||||
reloTypeSize /* type size in bytes */
|
||||
reloEnumvalExists /* enum value existence in target kernel */
|
||||
reloEnumvalValue /* enum value integer value */
|
||||
)
|
||||
|
||||
func (k coreReloKind) String() string {
|
||||
switch k {
|
||||
case reloFieldByteOffset:
|
||||
return "byte_off"
|
||||
case reloFieldByteSize:
|
||||
return "byte_sz"
|
||||
case reloFieldExists:
|
||||
return "field_exists"
|
||||
case reloFieldSigned:
|
||||
return "signed"
|
||||
case reloFieldLShiftU64:
|
||||
return "lshift_u64"
|
||||
case reloFieldRShiftU64:
|
||||
return "rshift_u64"
|
||||
case reloTypeIDLocal:
|
||||
return "local_type_id"
|
||||
case reloTypeIDTarget:
|
||||
return "target_type_id"
|
||||
case reloTypeExists:
|
||||
return "type_exists"
|
||||
case reloTypeSize:
|
||||
return "type_size"
|
||||
case reloEnumvalExists:
|
||||
return "enumval_exists"
|
||||
case reloEnumvalValue:
|
||||
return "enumval_value"
|
||||
default:
|
||||
return "unknown"
|
||||
}
|
||||
}
|
||||
|
||||
func coreRelocate(local, target *Spec, coreRelos bpfCoreRelos) (map[uint64]Relocation, error) {
|
||||
if target == nil {
|
||||
var err error
|
||||
target, err = loadKernelSpec()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
}
|
||||
|
||||
if local.byteOrder != target.byteOrder {
|
||||
return nil, fmt.Errorf("can't relocate %s against %s", local.byteOrder, target.byteOrder)
|
||||
}
|
||||
|
||||
relocations := make(map[uint64]Relocation, len(coreRelos))
|
||||
for _, relo := range coreRelos {
|
||||
accessorStr, err := local.strings.Lookup(relo.AccessStrOff)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
accessor, err := parseCoreAccessor(accessorStr)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("accessor %q: %s", accessorStr, err)
|
||||
}
|
||||
|
||||
if int(relo.TypeID) >= len(local.types) {
|
||||
return nil, fmt.Errorf("invalid type id %d", relo.TypeID)
|
||||
}
|
||||
|
||||
typ := local.types[relo.TypeID]
|
||||
|
||||
if relo.ReloKind == reloTypeIDLocal {
|
||||
relocations[uint64(relo.InsnOff)] = Relocation{
|
||||
uint32(typ.ID()),
|
||||
uint32(typ.ID()),
|
||||
}
|
||||
continue
|
||||
}
|
||||
|
||||
named, ok := typ.(namedType)
|
||||
if !ok || named.name() == "" {
|
||||
return nil, fmt.Errorf("relocate anonymous type %s: %w", typ.String(), ErrNotSupported)
|
||||
}
|
||||
|
||||
name := essentialName(named.name())
|
||||
res, err := coreCalculateRelocation(typ, target.namedTypes[name], relo.ReloKind, accessor)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("relocate %s: %w", name, err)
|
||||
}
|
||||
|
||||
relocations[uint64(relo.InsnOff)] = res
|
||||
}
|
||||
|
||||
return relocations, nil
|
||||
}
|
||||
|
||||
var errAmbiguousRelocation = errors.New("ambiguous relocation")
|
||||
|
||||
func coreCalculateRelocation(local Type, targets []namedType, kind coreReloKind, localAccessor coreAccessor) (Relocation, error) {
|
||||
var relos []Relocation
|
||||
var matches []Type
|
||||
for _, target := range targets {
|
||||
switch kind {
|
||||
case reloTypeIDTarget:
|
||||
if localAccessor[0] != 0 {
|
||||
return Relocation{}, fmt.Errorf("%s: unexpected non-zero accessor", kind)
|
||||
}
|
||||
|
||||
if compat, err := coreAreTypesCompatible(local, target); err != nil {
|
||||
return Relocation{}, fmt.Errorf("%s: %s", kind, err)
|
||||
} else if !compat {
|
||||
continue
|
||||
}
|
||||
|
||||
relos = append(relos, Relocation{uint32(target.ID()), uint32(target.ID())})
|
||||
|
||||
default:
|
||||
return Relocation{}, fmt.Errorf("relocation %s: %w", kind, ErrNotSupported)
|
||||
}
|
||||
matches = append(matches, target)
|
||||
}
|
||||
|
||||
if len(relos) == 0 {
|
||||
// TODO: Add switch for existence checks like reloEnumvalExists here.
|
||||
|
||||
// TODO: This might have to be poisoned.
|
||||
return Relocation{}, fmt.Errorf("no relocation found, tried %v", targets)
|
||||
}
|
||||
|
||||
relo := relos[0]
|
||||
for _, altRelo := range relos[1:] {
|
||||
if !altRelo.equal(relo) {
|
||||
return Relocation{}, fmt.Errorf("multiple types %v match: %w", matches, errAmbiguousRelocation)
|
||||
}
|
||||
}
|
||||
|
||||
return relo, nil
|
||||
}
|
||||
|
||||
/* coreAccessor contains a path through a struct. It contains at least one index.
|
||||
*
|
||||
* The interpretation depends on the kind of the relocation. The following is
|
||||
* taken from struct bpf_core_relo in libbpf_internal.h:
|
||||
*
|
||||
* - for field-based relocations, string encodes an accessed field using
|
||||
* a sequence of field and array indices, separated by colon (:). It's
|
||||
* conceptually very close to LLVM's getelementptr ([0]) instruction's
|
||||
* arguments for identifying offset to a field.
|
||||
* - for type-based relocations, strings is expected to be just "0";
|
||||
* - for enum value-based relocations, string contains an index of enum
|
||||
* value within its enum type;
|
||||
*
|
||||
* Example to provide a better feel.
|
||||
*
|
||||
* struct sample {
|
||||
* int a;
|
||||
* struct {
|
||||
* int b[10];
|
||||
* };
|
||||
* };
|
||||
*
|
||||
* struct sample s = ...;
|
||||
* int x = &s->a; // encoded as "0:0" (a is field #0)
|
||||
* int y = &s->b[5]; // encoded as "0:1:0:5" (anon struct is field #1,
|
||||
* // b is field #0 inside anon struct, accessing elem #5)
|
||||
* int z = &s[10]->b; // encoded as "10:1" (ptr is used as an array)
|
||||
*/
|
||||
type coreAccessor []int
|
||||
|
||||
func parseCoreAccessor(accessor string) (coreAccessor, error) {
|
||||
if accessor == "" {
|
||||
return nil, fmt.Errorf("empty accessor")
|
||||
}
|
||||
|
||||
var result coreAccessor
|
||||
parts := strings.Split(accessor, ":")
|
||||
for _, part := range parts {
|
||||
// 31 bits to avoid overflowing int on 32 bit platforms.
|
||||
index, err := strconv.ParseUint(part, 10, 31)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("accessor index %q: %s", part, err)
|
||||
}
|
||||
|
||||
result = append(result, int(index))
|
||||
}
|
||||
|
||||
return result, nil
|
||||
}
|
||||
|
||||
/* The comment below is from bpf_core_types_are_compat in libbpf.c:
|
||||
*
|
||||
* Check local and target types for compatibility. This check is used for
|
||||
* type-based CO-RE relocations and follow slightly different rules than
|
||||
* field-based relocations. This function assumes that root types were already
|
||||
* checked for name match. Beyond that initial root-level name check, names
|
||||
* are completely ignored. Compatibility rules are as follows:
|
||||
* - any two STRUCTs/UNIONs/FWDs/ENUMs/INTs are considered compatible, but
|
||||
* kind should match for local and target types (i.e., STRUCT is not
|
||||
* compatible with UNION);
|
||||
* - for ENUMs, the size is ignored;
|
||||
* - for INT, size and signedness are ignored;
|
||||
* - for ARRAY, dimensionality is ignored, element types are checked for
|
||||
* compatibility recursively;
|
||||
* - CONST/VOLATILE/RESTRICT modifiers are ignored;
|
||||
* - TYPEDEFs/PTRs are compatible if types they pointing to are compatible;
|
||||
* - FUNC_PROTOs are compatible if they have compatible signature: same
|
||||
* number of input args and compatible return and argument types.
|
||||
* These rules are not set in stone and probably will be adjusted as we get
|
||||
* more experience with using BPF CO-RE relocations.
|
||||
*/
|
||||
func coreAreTypesCompatible(localType Type, targetType Type) (bool, error) {
|
||||
var (
|
||||
localTs, targetTs typeDeque
|
||||
l, t = &localType, &targetType
|
||||
depth = 0
|
||||
)
|
||||
|
||||
for ; l != nil && t != nil; l, t = localTs.shift(), targetTs.shift() {
|
||||
if depth >= maxTypeDepth {
|
||||
return false, errors.New("types are nested too deep")
|
||||
}
|
||||
|
||||
localType = skipQualifierAndTypedef(*l)
|
||||
targetType = skipQualifierAndTypedef(*t)
|
||||
|
||||
if reflect.TypeOf(localType) != reflect.TypeOf(targetType) {
|
||||
return false, nil
|
||||
}
|
||||
|
||||
switch lv := (localType).(type) {
|
||||
case *Void, *Struct, *Union, *Enum, *Fwd:
|
||||
// Nothing to do here
|
||||
|
||||
case *Int:
|
||||
tv := targetType.(*Int)
|
||||
if lv.isBitfield() || tv.isBitfield() {
|
||||
return false, nil
|
||||
}
|
||||
|
||||
case *Pointer, *Array:
|
||||
depth++
|
||||
localType.walk(&localTs)
|
||||
targetType.walk(&targetTs)
|
||||
|
||||
case *FuncProto:
|
||||
tv := targetType.(*FuncProto)
|
||||
if len(lv.Params) != len(tv.Params) {
|
||||
return false, nil
|
||||
}
|
||||
|
||||
depth++
|
||||
localType.walk(&localTs)
|
||||
targetType.walk(&targetTs)
|
||||
|
||||
default:
|
||||
return false, fmt.Errorf("unsupported type %T", localType)
|
||||
}
|
||||
}
|
||||
|
||||
if l != nil {
|
||||
return false, fmt.Errorf("dangling local type %T", *l)
|
||||
}
|
||||
|
||||
if t != nil {
|
||||
return false, fmt.Errorf("dangling target type %T", *t)
|
||||
}
|
||||
|
||||
return true, nil
|
||||
}
|
||||
|
||||
/* The comment below is from bpf_core_fields_are_compat in libbpf.c:
|
||||
*
|
||||
* Check two types for compatibility for the purpose of field access
|
||||
* relocation. const/volatile/restrict and typedefs are skipped to ensure we
|
||||
* are relocating semantically compatible entities:
|
||||
* - any two STRUCTs/UNIONs are compatible and can be mixed;
|
||||
* - any two FWDs are compatible, if their names match (modulo flavor suffix);
|
||||
* - any two PTRs are always compatible;
|
||||
* - for ENUMs, names should be the same (ignoring flavor suffix) or at
|
||||
* least one of enums should be anonymous;
|
||||
* - for ENUMs, check sizes, names are ignored;
|
||||
* - for INT, size and signedness are ignored;
|
||||
* - for ARRAY, dimensionality is ignored, element types are checked for
|
||||
* compatibility recursively;
|
||||
* - everything else shouldn't be ever a target of relocation.
|
||||
* These rules are not set in stone and probably will be adjusted as we get
|
||||
* more experience with using BPF CO-RE relocations.
|
||||
*/
|
||||
func coreAreMembersCompatible(localType Type, targetType Type) (bool, error) {
|
||||
doNamesMatch := func(a, b string) bool {
|
||||
if a == "" || b == "" {
|
||||
// allow anonymous and named type to match
|
||||
return true
|
||||
}
|
||||
|
||||
return essentialName(a) == essentialName(b)
|
||||
}
|
||||
|
||||
for depth := 0; depth <= maxTypeDepth; depth++ {
|
||||
localType = skipQualifierAndTypedef(localType)
|
||||
targetType = skipQualifierAndTypedef(targetType)
|
||||
|
||||
_, lok := localType.(composite)
|
||||
_, tok := targetType.(composite)
|
||||
if lok && tok {
|
||||
return true, nil
|
||||
}
|
||||
|
||||
if reflect.TypeOf(localType) != reflect.TypeOf(targetType) {
|
||||
return false, nil
|
||||
}
|
||||
|
||||
switch lv := localType.(type) {
|
||||
case *Pointer:
|
||||
return true, nil
|
||||
|
||||
case *Enum:
|
||||
tv := targetType.(*Enum)
|
||||
return doNamesMatch(lv.name(), tv.name()), nil
|
||||
|
||||
case *Fwd:
|
||||
tv := targetType.(*Fwd)
|
||||
return doNamesMatch(lv.name(), tv.name()), nil
|
||||
|
||||
case *Int:
|
||||
tv := targetType.(*Int)
|
||||
return !lv.isBitfield() && !tv.isBitfield(), nil
|
||||
|
||||
case *Array:
|
||||
tv := targetType.(*Array)
|
||||
|
||||
localType = lv.Type
|
||||
targetType = tv.Type
|
||||
|
||||
default:
|
||||
return false, fmt.Errorf("unsupported type %T", localType)
|
||||
}
|
||||
}
|
||||
|
||||
return false, errors.New("types are nested too deep")
|
||||
}
|
||||
|
||||
func skipQualifierAndTypedef(typ Type) Type {
|
||||
result := typ
|
||||
for depth := 0; depth <= maxTypeDepth; depth++ {
|
||||
switch v := (result).(type) {
|
||||
case qualifier:
|
||||
result = v.qualify()
|
||||
case *Typedef:
|
||||
result = v.Type
|
||||
default:
|
||||
return result
|
||||
}
|
||||
}
|
||||
return typ
|
||||
}
|
|
@ -1,281 +0,0 @@
|
|||
package btf
|
||||
|
||||
import (
|
||||
"bufio"
|
||||
"bytes"
|
||||
"encoding/binary"
|
||||
"errors"
|
||||
"fmt"
|
||||
"io"
|
||||
"io/ioutil"
|
||||
|
||||
"github.com/cilium/ebpf/asm"
|
||||
"github.com/cilium/ebpf/internal"
|
||||
)
|
||||
|
||||
type btfExtHeader struct {
|
||||
Magic uint16
|
||||
Version uint8
|
||||
Flags uint8
|
||||
HdrLen uint32
|
||||
|
||||
FuncInfoOff uint32
|
||||
FuncInfoLen uint32
|
||||
LineInfoOff uint32
|
||||
LineInfoLen uint32
|
||||
}
|
||||
|
||||
type btfExtCoreHeader struct {
|
||||
CoreReloOff uint32
|
||||
CoreReloLen uint32
|
||||
}
|
||||
|
||||
func parseExtInfos(r io.ReadSeeker, bo binary.ByteOrder, strings stringTable) (funcInfo, lineInfo map[string]extInfo, coreRelos map[string]bpfCoreRelos, err error) {
|
||||
var header btfExtHeader
|
||||
var coreHeader btfExtCoreHeader
|
||||
if err := binary.Read(r, bo, &header); err != nil {
|
||||
return nil, nil, nil, fmt.Errorf("can't read header: %v", err)
|
||||
}
|
||||
|
||||
if header.Magic != btfMagic {
|
||||
return nil, nil, nil, fmt.Errorf("incorrect magic value %v", header.Magic)
|
||||
}
|
||||
|
||||
if header.Version != 1 {
|
||||
return nil, nil, nil, fmt.Errorf("unexpected version %v", header.Version)
|
||||
}
|
||||
|
||||
if header.Flags != 0 {
|
||||
return nil, nil, nil, fmt.Errorf("unsupported flags %v", header.Flags)
|
||||
}
|
||||
|
||||
remainder := int64(header.HdrLen) - int64(binary.Size(&header))
|
||||
if remainder < 0 {
|
||||
return nil, nil, nil, errors.New("header is too short")
|
||||
}
|
||||
|
||||
coreHdrSize := int64(binary.Size(&coreHeader))
|
||||
if remainder >= coreHdrSize {
|
||||
if err := binary.Read(r, bo, &coreHeader); err != nil {
|
||||
return nil, nil, nil, fmt.Errorf("can't read CO-RE relocation header: %v", err)
|
||||
}
|
||||
remainder -= coreHdrSize
|
||||
}
|
||||
|
||||
// Of course, the .BTF.ext header has different semantics than the
|
||||
// .BTF ext header. We need to ignore non-null values.
|
||||
_, err = io.CopyN(ioutil.Discard, r, remainder)
|
||||
if err != nil {
|
||||
return nil, nil, nil, fmt.Errorf("header padding: %v", err)
|
||||
}
|
||||
|
||||
if _, err := r.Seek(int64(header.HdrLen+header.FuncInfoOff), io.SeekStart); err != nil {
|
||||
return nil, nil, nil, fmt.Errorf("can't seek to function info section: %v", err)
|
||||
}
|
||||
|
||||
buf := bufio.NewReader(io.LimitReader(r, int64(header.FuncInfoLen)))
|
||||
funcInfo, err = parseExtInfo(buf, bo, strings)
|
||||
if err != nil {
|
||||
return nil, nil, nil, fmt.Errorf("function info: %w", err)
|
||||
}
|
||||
|
||||
if _, err := r.Seek(int64(header.HdrLen+header.LineInfoOff), io.SeekStart); err != nil {
|
||||
return nil, nil, nil, fmt.Errorf("can't seek to line info section: %v", err)
|
||||
}
|
||||
|
||||
buf = bufio.NewReader(io.LimitReader(r, int64(header.LineInfoLen)))
|
||||
lineInfo, err = parseExtInfo(buf, bo, strings)
|
||||
if err != nil {
|
||||
return nil, nil, nil, fmt.Errorf("line info: %w", err)
|
||||
}
|
||||
|
||||
if coreHeader.CoreReloOff > 0 && coreHeader.CoreReloLen > 0 {
|
||||
if _, err := r.Seek(int64(header.HdrLen+coreHeader.CoreReloOff), io.SeekStart); err != nil {
|
||||
return nil, nil, nil, fmt.Errorf("can't seek to CO-RE relocation section: %v", err)
|
||||
}
|
||||
|
||||
coreRelos, err = parseExtInfoRelos(io.LimitReader(r, int64(coreHeader.CoreReloLen)), bo, strings)
|
||||
if err != nil {
|
||||
return nil, nil, nil, fmt.Errorf("CO-RE relocation info: %w", err)
|
||||
}
|
||||
}
|
||||
|
||||
return funcInfo, lineInfo, coreRelos, nil
|
||||
}
|
||||
|
||||
type btfExtInfoSec struct {
|
||||
SecNameOff uint32
|
||||
NumInfo uint32
|
||||
}
|
||||
|
||||
type extInfoRecord struct {
|
||||
InsnOff uint64
|
||||
Opaque []byte
|
||||
}
|
||||
|
||||
type extInfo struct {
|
||||
recordSize uint32
|
||||
records []extInfoRecord
|
||||
}
|
||||
|
||||
func (ei extInfo) append(other extInfo, offset uint64) (extInfo, error) {
|
||||
if other.recordSize != ei.recordSize {
|
||||
return extInfo{}, fmt.Errorf("ext_info record size mismatch, want %d (got %d)", ei.recordSize, other.recordSize)
|
||||
}
|
||||
|
||||
records := make([]extInfoRecord, 0, len(ei.records)+len(other.records))
|
||||
records = append(records, ei.records...)
|
||||
for _, info := range other.records {
|
||||
records = append(records, extInfoRecord{
|
||||
InsnOff: info.InsnOff + offset,
|
||||
Opaque: info.Opaque,
|
||||
})
|
||||
}
|
||||
return extInfo{ei.recordSize, records}, nil
|
||||
}
|
||||
|
||||
func (ei extInfo) MarshalBinary() ([]byte, error) {
|
||||
if len(ei.records) == 0 {
|
||||
return nil, nil
|
||||
}
|
||||
|
||||
buf := bytes.NewBuffer(make([]byte, 0, int(ei.recordSize)*len(ei.records)))
|
||||
for _, info := range ei.records {
|
||||
// The kernel expects offsets in number of raw bpf instructions,
|
||||
// while the ELF tracks it in bytes.
|
||||
insnOff := uint32(info.InsnOff / asm.InstructionSize)
|
||||
if err := binary.Write(buf, internal.NativeEndian, insnOff); err != nil {
|
||||
return nil, fmt.Errorf("can't write instruction offset: %v", err)
|
||||
}
|
||||
|
||||
buf.Write(info.Opaque)
|
||||
}
|
||||
|
||||
return buf.Bytes(), nil
|
||||
}
|
||||
|
||||
func parseExtInfo(r io.Reader, bo binary.ByteOrder, strings stringTable) (map[string]extInfo, error) {
|
||||
const maxRecordSize = 256
|
||||
|
||||
var recordSize uint32
|
||||
if err := binary.Read(r, bo, &recordSize); err != nil {
|
||||
return nil, fmt.Errorf("can't read record size: %v", err)
|
||||
}
|
||||
|
||||
if recordSize < 4 {
|
||||
// Need at least insnOff
|
||||
return nil, errors.New("record size too short")
|
||||
}
|
||||
if recordSize > maxRecordSize {
|
||||
return nil, fmt.Errorf("record size %v exceeds %v", recordSize, maxRecordSize)
|
||||
}
|
||||
|
||||
result := make(map[string]extInfo)
|
||||
for {
|
||||
secName, infoHeader, err := parseExtInfoHeader(r, bo, strings)
|
||||
if errors.Is(err, io.EOF) {
|
||||
return result, nil
|
||||
}
|
||||
|
||||
var records []extInfoRecord
|
||||
for i := uint32(0); i < infoHeader.NumInfo; i++ {
|
||||
var byteOff uint32
|
||||
if err := binary.Read(r, bo, &byteOff); err != nil {
|
||||
return nil, fmt.Errorf("section %v: can't read extended info offset: %v", secName, err)
|
||||
}
|
||||
|
||||
buf := make([]byte, int(recordSize-4))
|
||||
if _, err := io.ReadFull(r, buf); err != nil {
|
||||
return nil, fmt.Errorf("section %v: can't read record: %v", secName, err)
|
||||
}
|
||||
|
||||
if byteOff%asm.InstructionSize != 0 {
|
||||
return nil, fmt.Errorf("section %v: offset %v is not aligned with instruction size", secName, byteOff)
|
||||
}
|
||||
|
||||
records = append(records, extInfoRecord{uint64(byteOff), buf})
|
||||
}
|
||||
|
||||
result[secName] = extInfo{
|
||||
recordSize,
|
||||
records,
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// bpfCoreRelo matches `struct bpf_core_relo` from the kernel
|
||||
type bpfCoreRelo struct {
|
||||
InsnOff uint32
|
||||
TypeID TypeID
|
||||
AccessStrOff uint32
|
||||
ReloKind coreReloKind
|
||||
}
|
||||
|
||||
type bpfCoreRelos []bpfCoreRelo
|
||||
|
||||
// append two slices of extInfoRelo to each other. The InsnOff of b are adjusted
|
||||
// by offset.
|
||||
func (r bpfCoreRelos) append(other bpfCoreRelos, offset uint64) bpfCoreRelos {
|
||||
result := make([]bpfCoreRelo, 0, len(r)+len(other))
|
||||
result = append(result, r...)
|
||||
for _, relo := range other {
|
||||
relo.InsnOff += uint32(offset)
|
||||
result = append(result, relo)
|
||||
}
|
||||
return result
|
||||
}
|
||||
|
||||
var extInfoReloSize = binary.Size(bpfCoreRelo{})
|
||||
|
||||
func parseExtInfoRelos(r io.Reader, bo binary.ByteOrder, strings stringTable) (map[string]bpfCoreRelos, error) {
|
||||
var recordSize uint32
|
||||
if err := binary.Read(r, bo, &recordSize); err != nil {
|
||||
return nil, fmt.Errorf("read record size: %v", err)
|
||||
}
|
||||
|
||||
if recordSize != uint32(extInfoReloSize) {
|
||||
return nil, fmt.Errorf("expected record size %d, got %d", extInfoReloSize, recordSize)
|
||||
}
|
||||
|
||||
result := make(map[string]bpfCoreRelos)
|
||||
for {
|
||||
secName, infoHeader, err := parseExtInfoHeader(r, bo, strings)
|
||||
if errors.Is(err, io.EOF) {
|
||||
return result, nil
|
||||
}
|
||||
|
||||
var relos []bpfCoreRelo
|
||||
for i := uint32(0); i < infoHeader.NumInfo; i++ {
|
||||
var relo bpfCoreRelo
|
||||
if err := binary.Read(r, bo, &relo); err != nil {
|
||||
return nil, fmt.Errorf("section %v: read record: %v", secName, err)
|
||||
}
|
||||
|
||||
if relo.InsnOff%asm.InstructionSize != 0 {
|
||||
return nil, fmt.Errorf("section %v: offset %v is not aligned with instruction size", secName, relo.InsnOff)
|
||||
}
|
||||
|
||||
relos = append(relos, relo)
|
||||
}
|
||||
|
||||
result[secName] = relos
|
||||
}
|
||||
}
|
||||
|
||||
func parseExtInfoHeader(r io.Reader, bo binary.ByteOrder, strings stringTable) (string, *btfExtInfoSec, error) {
|
||||
var infoHeader btfExtInfoSec
|
||||
if err := binary.Read(r, bo, &infoHeader); err != nil {
|
||||
return "", nil, fmt.Errorf("read ext info header: %w", err)
|
||||
}
|
||||
|
||||
secName, err := strings.Lookup(infoHeader.SecNameOff)
|
||||
if err != nil {
|
||||
return "", nil, fmt.Errorf("get section name: %w", err)
|
||||
}
|
||||
|
||||
if infoHeader.NumInfo == 0 {
|
||||
return "", nil, fmt.Errorf("section %s has zero records", secName)
|
||||
}
|
||||
|
||||
return secName, &infoHeader, nil
|
||||
}
|
|
@ -1,49 +0,0 @@
|
|||
// +build gofuzz
|
||||
|
||||
// Use with https://github.com/dvyukov/go-fuzz
|
||||
|
||||
package btf
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"encoding/binary"
|
||||
|
||||
"github.com/cilium/ebpf/internal"
|
||||
)
|
||||
|
||||
func FuzzSpec(data []byte) int {
|
||||
if len(data) < binary.Size(btfHeader{}) {
|
||||
return -1
|
||||
}
|
||||
|
||||
spec, err := loadNakedSpec(bytes.NewReader(data), internal.NativeEndian, nil, nil)
|
||||
if err != nil {
|
||||
if spec != nil {
|
||||
panic("spec is not nil")
|
||||
}
|
||||
return 0
|
||||
}
|
||||
if spec == nil {
|
||||
panic("spec is nil")
|
||||
}
|
||||
return 1
|
||||
}
|
||||
|
||||
func FuzzExtInfo(data []byte) int {
|
||||
if len(data) < binary.Size(btfExtHeader{}) {
|
||||
return -1
|
||||
}
|
||||
|
||||
table := stringTable("\x00foo\x00barfoo\x00")
|
||||
info, err := parseExtInfo(bytes.NewReader(data), internal.NativeEndian, table)
|
||||
if err != nil {
|
||||
if info != nil {
|
||||
panic("info is not nil")
|
||||
}
|
||||
return 0
|
||||
}
|
||||
if info == nil {
|
||||
panic("info is nil")
|
||||
}
|
||||
return 1
|
||||
}
|
|
@ -1,60 +0,0 @@
|
|||
package btf
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"errors"
|
||||
"fmt"
|
||||
"io"
|
||||
"io/ioutil"
|
||||
)
|
||||
|
||||
type stringTable []byte
|
||||
|
||||
func readStringTable(r io.Reader) (stringTable, error) {
|
||||
contents, err := ioutil.ReadAll(r)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("can't read string table: %v", err)
|
||||
}
|
||||
|
||||
if len(contents) < 1 {
|
||||
return nil, errors.New("string table is empty")
|
||||
}
|
||||
|
||||
if contents[0] != '\x00' {
|
||||
return nil, errors.New("first item in string table is non-empty")
|
||||
}
|
||||
|
||||
if contents[len(contents)-1] != '\x00' {
|
||||
return nil, errors.New("string table isn't null terminated")
|
||||
}
|
||||
|
||||
return stringTable(contents), nil
|
||||
}
|
||||
|
||||
func (st stringTable) Lookup(offset uint32) (string, error) {
|
||||
if int64(offset) > int64(^uint(0)>>1) {
|
||||
return "", fmt.Errorf("offset %d overflows int", offset)
|
||||
}
|
||||
|
||||
pos := int(offset)
|
||||
if pos >= len(st) {
|
||||
return "", fmt.Errorf("offset %d is out of bounds", offset)
|
||||
}
|
||||
|
||||
if pos > 0 && st[pos-1] != '\x00' {
|
||||
return "", fmt.Errorf("offset %d isn't start of a string", offset)
|
||||
}
|
||||
|
||||
str := st[pos:]
|
||||
end := bytes.IndexByte(str, '\x00')
|
||||
if end == -1 {
|
||||
return "", fmt.Errorf("offset %d isn't null terminated", offset)
|
||||
}
|
||||
|
||||
return string(str[:end]), nil
|
||||
}
|
||||
|
||||
func (st stringTable) LookupName(offset uint32) (Name, error) {
|
||||
str, err := st.Lookup(offset)
|
||||
return Name(str), err
|
||||
}
|
|
@ -1,871 +0,0 @@
|
|||
package btf
|
||||
|
||||
import (
|
||||
"errors"
|
||||
"fmt"
|
||||
"math"
|
||||
"strings"
|
||||
)
|
||||
|
||||
const maxTypeDepth = 32
|
||||
|
||||
// TypeID identifies a type in a BTF section.
|
||||
type TypeID uint32
|
||||
|
||||
// ID implements part of the Type interface.
|
||||
func (tid TypeID) ID() TypeID {
|
||||
return tid
|
||||
}
|
||||
|
||||
// Type represents a type described by BTF.
|
||||
type Type interface {
|
||||
ID() TypeID
|
||||
|
||||
String() string
|
||||
|
||||
// Make a copy of the type, without copying Type members.
|
||||
copy() Type
|
||||
|
||||
// Enumerate all nested Types. Repeated calls must visit nested
|
||||
// types in the same order.
|
||||
walk(*typeDeque)
|
||||
}
|
||||
|
||||
// namedType is a type with a name.
|
||||
//
|
||||
// Most named types simply embed Name.
|
||||
type namedType interface {
|
||||
Type
|
||||
name() string
|
||||
}
|
||||
|
||||
// Name identifies a type.
|
||||
//
|
||||
// Anonymous types have an empty name.
|
||||
type Name string
|
||||
|
||||
func (n Name) name() string {
|
||||
return string(n)
|
||||
}
|
||||
|
||||
// Void is the unit type of BTF.
|
||||
type Void struct{}
|
||||
|
||||
func (v *Void) ID() TypeID { return 0 }
|
||||
func (v *Void) String() string { return "void#0" }
|
||||
func (v *Void) size() uint32 { return 0 }
|
||||
func (v *Void) copy() Type { return (*Void)(nil) }
|
||||
func (v *Void) walk(*typeDeque) {}
|
||||
|
||||
type IntEncoding byte
|
||||
|
||||
const (
|
||||
Signed IntEncoding = 1 << iota
|
||||
Char
|
||||
Bool
|
||||
)
|
||||
|
||||
// Int is an integer of a given length.
|
||||
type Int struct {
|
||||
TypeID
|
||||
Name
|
||||
|
||||
// The size of the integer in bytes.
|
||||
Size uint32
|
||||
Encoding IntEncoding
|
||||
// Offset is the starting bit offset. Currently always 0.
|
||||
// See https://www.kernel.org/doc/html/latest/bpf/btf.html#btf-kind-int
|
||||
Offset uint32
|
||||
Bits byte
|
||||
}
|
||||
|
||||
var _ namedType = (*Int)(nil)
|
||||
|
||||
func (i *Int) String() string {
|
||||
var s strings.Builder
|
||||
|
||||
switch {
|
||||
case i.Encoding&Char != 0:
|
||||
s.WriteString("char")
|
||||
case i.Encoding&Bool != 0:
|
||||
s.WriteString("bool")
|
||||
default:
|
||||
if i.Encoding&Signed == 0 {
|
||||
s.WriteRune('u')
|
||||
}
|
||||
s.WriteString("int")
|
||||
fmt.Fprintf(&s, "%d", i.Size*8)
|
||||
}
|
||||
|
||||
fmt.Fprintf(&s, "#%d", i.TypeID)
|
||||
|
||||
if i.Bits > 0 {
|
||||
fmt.Fprintf(&s, "[bits=%d]", i.Bits)
|
||||
}
|
||||
|
||||
return s.String()
|
||||
}
|
||||
|
||||
func (i *Int) size() uint32 { return i.Size }
|
||||
func (i *Int) walk(*typeDeque) {}
|
||||
func (i *Int) copy() Type {
|
||||
cpy := *i
|
||||
return &cpy
|
||||
}
|
||||
|
||||
func (i *Int) isBitfield() bool {
|
||||
return i.Offset > 0
|
||||
}
|
||||
|
||||
// Pointer is a pointer to another type.
|
||||
type Pointer struct {
|
||||
TypeID
|
||||
Target Type
|
||||
}
|
||||
|
||||
func (p *Pointer) String() string {
|
||||
return fmt.Sprintf("pointer#%d[target=#%d]", p.TypeID, p.Target.ID())
|
||||
}
|
||||
|
||||
func (p *Pointer) size() uint32 { return 8 }
|
||||
func (p *Pointer) walk(tdq *typeDeque) { tdq.push(&p.Target) }
|
||||
func (p *Pointer) copy() Type {
|
||||
cpy := *p
|
||||
return &cpy
|
||||
}
|
||||
|
||||
// Array is an array with a fixed number of elements.
|
||||
type Array struct {
|
||||
TypeID
|
||||
Type Type
|
||||
Nelems uint32
|
||||
}
|
||||
|
||||
func (arr *Array) String() string {
|
||||
return fmt.Sprintf("array#%d[type=#%d n=%d]", arr.TypeID, arr.Type.ID(), arr.Nelems)
|
||||
}
|
||||
|
||||
func (arr *Array) walk(tdq *typeDeque) { tdq.push(&arr.Type) }
|
||||
func (arr *Array) copy() Type {
|
||||
cpy := *arr
|
||||
return &cpy
|
||||
}
|
||||
|
||||
// Struct is a compound type of consecutive members.
|
||||
type Struct struct {
|
||||
TypeID
|
||||
Name
|
||||
// The size of the struct including padding, in bytes
|
||||
Size uint32
|
||||
Members []Member
|
||||
}
|
||||
|
||||
func (s *Struct) String() string {
|
||||
return fmt.Sprintf("struct#%d[%q]", s.TypeID, s.Name)
|
||||
}
|
||||
|
||||
func (s *Struct) size() uint32 { return s.Size }
|
||||
|
||||
func (s *Struct) walk(tdq *typeDeque) {
|
||||
for i := range s.Members {
|
||||
tdq.push(&s.Members[i].Type)
|
||||
}
|
||||
}
|
||||
|
||||
func (s *Struct) copy() Type {
|
||||
cpy := *s
|
||||
cpy.Members = make([]Member, len(s.Members))
|
||||
copy(cpy.Members, s.Members)
|
||||
return &cpy
|
||||
}
|
||||
|
||||
func (s *Struct) members() []Member {
|
||||
return s.Members
|
||||
}
|
||||
|
||||
// Union is a compound type where members occupy the same memory.
|
||||
type Union struct {
|
||||
TypeID
|
||||
Name
|
||||
// The size of the union including padding, in bytes.
|
||||
Size uint32
|
||||
Members []Member
|
||||
}
|
||||
|
||||
func (u *Union) String() string {
|
||||
return fmt.Sprintf("union#%d[%q]", u.TypeID, u.Name)
|
||||
}
|
||||
|
||||
func (u *Union) size() uint32 { return u.Size }
|
||||
|
||||
func (u *Union) walk(tdq *typeDeque) {
|
||||
for i := range u.Members {
|
||||
tdq.push(&u.Members[i].Type)
|
||||
}
|
||||
}
|
||||
|
||||
func (u *Union) copy() Type {
|
||||
cpy := *u
|
||||
cpy.Members = make([]Member, len(u.Members))
|
||||
copy(cpy.Members, u.Members)
|
||||
return &cpy
|
||||
}
|
||||
|
||||
func (u *Union) members() []Member {
|
||||
return u.Members
|
||||
}
|
||||
|
||||
type composite interface {
|
||||
members() []Member
|
||||
}
|
||||
|
||||
var (
|
||||
_ composite = (*Struct)(nil)
|
||||
_ composite = (*Union)(nil)
|
||||
)
|
||||
|
||||
// Member is part of a Struct or Union.
|
||||
//
|
||||
// It is not a valid Type.
|
||||
type Member struct {
|
||||
Name
|
||||
Type Type
|
||||
// Offset is the bit offset of this member
|
||||
Offset uint32
|
||||
BitfieldSize uint32
|
||||
}
|
||||
|
||||
// Enum lists possible values.
|
||||
type Enum struct {
|
||||
TypeID
|
||||
Name
|
||||
Values []EnumValue
|
||||
}
|
||||
|
||||
func (e *Enum) String() string {
|
||||
return fmt.Sprintf("enum#%d[%q]", e.TypeID, e.Name)
|
||||
}
|
||||
|
||||
// EnumValue is part of an Enum
|
||||
//
|
||||
// Is is not a valid Type
|
||||
type EnumValue struct {
|
||||
Name
|
||||
Value int32
|
||||
}
|
||||
|
||||
func (e *Enum) size() uint32 { return 4 }
|
||||
func (e *Enum) walk(*typeDeque) {}
|
||||
func (e *Enum) copy() Type {
|
||||
cpy := *e
|
||||
cpy.Values = make([]EnumValue, len(e.Values))
|
||||
copy(cpy.Values, e.Values)
|
||||
return &cpy
|
||||
}
|
||||
|
||||
// FwdKind is the type of forward declaration.
|
||||
type FwdKind int
|
||||
|
||||
// Valid types of forward declaration.
|
||||
const (
|
||||
FwdStruct FwdKind = iota
|
||||
FwdUnion
|
||||
)
|
||||
|
||||
func (fk FwdKind) String() string {
|
||||
switch fk {
|
||||
case FwdStruct:
|
||||
return "struct"
|
||||
case FwdUnion:
|
||||
return "union"
|
||||
default:
|
||||
return fmt.Sprintf("%T(%d)", fk, int(fk))
|
||||
}
|
||||
}
|
||||
|
||||
// Fwd is a forward declaration of a Type.
|
||||
type Fwd struct {
|
||||
TypeID
|
||||
Name
|
||||
Kind FwdKind
|
||||
}
|
||||
|
||||
func (f *Fwd) String() string {
|
||||
return fmt.Sprintf("fwd#%d[%s %q]", f.TypeID, f.Kind, f.Name)
|
||||
}
|
||||
|
||||
func (f *Fwd) walk(*typeDeque) {}
|
||||
func (f *Fwd) copy() Type {
|
||||
cpy := *f
|
||||
return &cpy
|
||||
}
|
||||
|
||||
// Typedef is an alias of a Type.
|
||||
type Typedef struct {
|
||||
TypeID
|
||||
Name
|
||||
Type Type
|
||||
}
|
||||
|
||||
func (td *Typedef) String() string {
|
||||
return fmt.Sprintf("typedef#%d[%q #%d]", td.TypeID, td.Name, td.Type.ID())
|
||||
}
|
||||
|
||||
func (td *Typedef) walk(tdq *typeDeque) { tdq.push(&td.Type) }
|
||||
func (td *Typedef) copy() Type {
|
||||
cpy := *td
|
||||
return &cpy
|
||||
}
|
||||
|
||||
// Volatile is a qualifier.
|
||||
type Volatile struct {
|
||||
TypeID
|
||||
Type Type
|
||||
}
|
||||
|
||||
func (v *Volatile) String() string {
|
||||
return fmt.Sprintf("volatile#%d[#%d]", v.TypeID, v.Type.ID())
|
||||
}
|
||||
|
||||
func (v *Volatile) qualify() Type { return v.Type }
|
||||
func (v *Volatile) walk(tdq *typeDeque) { tdq.push(&v.Type) }
|
||||
func (v *Volatile) copy() Type {
|
||||
cpy := *v
|
||||
return &cpy
|
||||
}
|
||||
|
||||
// Const is a qualifier.
|
||||
type Const struct {
|
||||
TypeID
|
||||
Type Type
|
||||
}
|
||||
|
||||
func (c *Const) String() string {
|
||||
return fmt.Sprintf("const#%d[#%d]", c.TypeID, c.Type.ID())
|
||||
}
|
||||
|
||||
func (c *Const) qualify() Type { return c.Type }
|
||||
func (c *Const) walk(tdq *typeDeque) { tdq.push(&c.Type) }
|
||||
func (c *Const) copy() Type {
|
||||
cpy := *c
|
||||
return &cpy
|
||||
}
|
||||
|
||||
// Restrict is a qualifier.
|
||||
type Restrict struct {
|
||||
TypeID
|
||||
Type Type
|
||||
}
|
||||
|
||||
func (r *Restrict) String() string {
|
||||
return fmt.Sprintf("restrict#%d[#%d]", r.TypeID, r.Type.ID())
|
||||
}
|
||||
|
||||
func (r *Restrict) qualify() Type { return r.Type }
|
||||
func (r *Restrict) walk(tdq *typeDeque) { tdq.push(&r.Type) }
|
||||
func (r *Restrict) copy() Type {
|
||||
cpy := *r
|
||||
return &cpy
|
||||
}
|
||||
|
||||
// Func is a function definition.
|
||||
type Func struct {
|
||||
TypeID
|
||||
Name
|
||||
Type Type
|
||||
}
|
||||
|
||||
func (f *Func) String() string {
|
||||
return fmt.Sprintf("func#%d[%q proto=#%d]", f.TypeID, f.Name, f.Type.ID())
|
||||
}
|
||||
|
||||
func (f *Func) walk(tdq *typeDeque) { tdq.push(&f.Type) }
|
||||
func (f *Func) copy() Type {
|
||||
cpy := *f
|
||||
return &cpy
|
||||
}
|
||||
|
||||
// FuncProto is a function declaration.
|
||||
type FuncProto struct {
|
||||
TypeID
|
||||
Return Type
|
||||
Params []FuncParam
|
||||
}
|
||||
|
||||
func (fp *FuncProto) String() string {
|
||||
var s strings.Builder
|
||||
fmt.Fprintf(&s, "proto#%d[", fp.TypeID)
|
||||
for _, param := range fp.Params {
|
||||
fmt.Fprintf(&s, "%q=#%d, ", param.Name, param.Type.ID())
|
||||
}
|
||||
fmt.Fprintf(&s, "return=#%d]", fp.Return.ID())
|
||||
return s.String()
|
||||
}
|
||||
|
||||
func (fp *FuncProto) walk(tdq *typeDeque) {
|
||||
tdq.push(&fp.Return)
|
||||
for i := range fp.Params {
|
||||
tdq.push(&fp.Params[i].Type)
|
||||
}
|
||||
}
|
||||
|
||||
func (fp *FuncProto) copy() Type {
|
||||
cpy := *fp
|
||||
cpy.Params = make([]FuncParam, len(fp.Params))
|
||||
copy(cpy.Params, fp.Params)
|
||||
return &cpy
|
||||
}
|
||||
|
||||
type FuncParam struct {
|
||||
Name
|
||||
Type Type
|
||||
}
|
||||
|
||||
// Var is a global variable.
|
||||
type Var struct {
|
||||
TypeID
|
||||
Name
|
||||
Type Type
|
||||
}
|
||||
|
||||
func (v *Var) String() string {
|
||||
// TODO: Linkage
|
||||
return fmt.Sprintf("var#%d[%q]", v.TypeID, v.Name)
|
||||
}
|
||||
|
||||
func (v *Var) walk(tdq *typeDeque) { tdq.push(&v.Type) }
|
||||
func (v *Var) copy() Type {
|
||||
cpy := *v
|
||||
return &cpy
|
||||
}
|
||||
|
||||
// Datasec is a global program section containing data.
|
||||
type Datasec struct {
|
||||
TypeID
|
||||
Name
|
||||
Size uint32
|
||||
Vars []VarSecinfo
|
||||
}
|
||||
|
||||
func (ds *Datasec) String() string {
|
||||
return fmt.Sprintf("section#%d[%q]", ds.TypeID, ds.Name)
|
||||
}
|
||||
|
||||
func (ds *Datasec) size() uint32 { return ds.Size }
|
||||
|
||||
func (ds *Datasec) walk(tdq *typeDeque) {
|
||||
for i := range ds.Vars {
|
||||
tdq.push(&ds.Vars[i].Type)
|
||||
}
|
||||
}
|
||||
|
||||
func (ds *Datasec) copy() Type {
|
||||
cpy := *ds
|
||||
cpy.Vars = make([]VarSecinfo, len(ds.Vars))
|
||||
copy(cpy.Vars, ds.Vars)
|
||||
return &cpy
|
||||
}
|
||||
|
||||
// VarSecinfo describes variable in a Datasec
|
||||
//
|
||||
// It is not a valid Type.
|
||||
type VarSecinfo struct {
|
||||
Type Type
|
||||
Offset uint32
|
||||
Size uint32
|
||||
}
|
||||
|
||||
type sizer interface {
|
||||
size() uint32
|
||||
}
|
||||
|
||||
var (
|
||||
_ sizer = (*Int)(nil)
|
||||
_ sizer = (*Pointer)(nil)
|
||||
_ sizer = (*Struct)(nil)
|
||||
_ sizer = (*Union)(nil)
|
||||
_ sizer = (*Enum)(nil)
|
||||
_ sizer = (*Datasec)(nil)
|
||||
)
|
||||
|
||||
type qualifier interface {
|
||||
qualify() Type
|
||||
}
|
||||
|
||||
var (
|
||||
_ qualifier = (*Const)(nil)
|
||||
_ qualifier = (*Restrict)(nil)
|
||||
_ qualifier = (*Volatile)(nil)
|
||||
)
|
||||
|
||||
// Sizeof returns the size of a type in bytes.
|
||||
//
|
||||
// Returns an error if the size can't be computed.
|
||||
func Sizeof(typ Type) (int, error) {
|
||||
var (
|
||||
n = int64(1)
|
||||
elem int64
|
||||
)
|
||||
|
||||
for i := 0; i < maxTypeDepth; i++ {
|
||||
switch v := typ.(type) {
|
||||
case *Array:
|
||||
if n > 0 && int64(v.Nelems) > math.MaxInt64/n {
|
||||
return 0, errors.New("overflow")
|
||||
}
|
||||
|
||||
// Arrays may be of zero length, which allows
|
||||
// n to be zero as well.
|
||||
n *= int64(v.Nelems)
|
||||
typ = v.Type
|
||||
continue
|
||||
|
||||
case sizer:
|
||||
elem = int64(v.size())
|
||||
|
||||
case *Typedef:
|
||||
typ = v.Type
|
||||
continue
|
||||
|
||||
case qualifier:
|
||||
typ = v.qualify()
|
||||
continue
|
||||
|
||||
default:
|
||||
return 0, fmt.Errorf("unrecognized type %T", typ)
|
||||
}
|
||||
|
||||
if n > 0 && elem > math.MaxInt64/n {
|
||||
return 0, errors.New("overflow")
|
||||
}
|
||||
|
||||
size := n * elem
|
||||
if int64(int(size)) != size {
|
||||
return 0, errors.New("overflow")
|
||||
}
|
||||
|
||||
return int(size), nil
|
||||
}
|
||||
|
||||
return 0, errors.New("exceeded type depth")
|
||||
}
|
||||
|
||||
// copy a Type recursively.
|
||||
//
|
||||
// typ may form a cycle.
|
||||
func copyType(typ Type) Type {
|
||||
var (
|
||||
copies = make(map[Type]Type)
|
||||
work typeDeque
|
||||
)
|
||||
|
||||
for t := &typ; t != nil; t = work.pop() {
|
||||
// *t is the identity of the type.
|
||||
if cpy := copies[*t]; cpy != nil {
|
||||
*t = cpy
|
||||
continue
|
||||
}
|
||||
|
||||
cpy := (*t).copy()
|
||||
copies[*t] = cpy
|
||||
*t = cpy
|
||||
|
||||
// Mark any nested types for copying.
|
||||
cpy.walk(&work)
|
||||
}
|
||||
|
||||
return typ
|
||||
}
|
||||
|
||||
// typeDeque keeps track of pointers to types which still
|
||||
// need to be visited.
|
||||
type typeDeque struct {
|
||||
types []*Type
|
||||
read, write uint64
|
||||
mask uint64
|
||||
}
|
||||
|
||||
// push adds a type to the stack.
|
||||
func (dq *typeDeque) push(t *Type) {
|
||||
if dq.write-dq.read < uint64(len(dq.types)) {
|
||||
dq.types[dq.write&dq.mask] = t
|
||||
dq.write++
|
||||
return
|
||||
}
|
||||
|
||||
new := len(dq.types) * 2
|
||||
if new == 0 {
|
||||
new = 8
|
||||
}
|
||||
|
||||
types := make([]*Type, new)
|
||||
pivot := dq.read & dq.mask
|
||||
n := copy(types, dq.types[pivot:])
|
||||
n += copy(types[n:], dq.types[:pivot])
|
||||
types[n] = t
|
||||
|
||||
dq.types = types
|
||||
dq.mask = uint64(new) - 1
|
||||
dq.read, dq.write = 0, uint64(n+1)
|
||||
}
|
||||
|
||||
// shift returns the first element or null.
|
||||
func (dq *typeDeque) shift() *Type {
|
||||
if dq.read == dq.write {
|
||||
return nil
|
||||
}
|
||||
|
||||
index := dq.read & dq.mask
|
||||
t := dq.types[index]
|
||||
dq.types[index] = nil
|
||||
dq.read++
|
||||
return t
|
||||
}
|
||||
|
||||
// pop returns the last element or null.
|
||||
func (dq *typeDeque) pop() *Type {
|
||||
if dq.read == dq.write {
|
||||
return nil
|
||||
}
|
||||
|
||||
dq.write--
|
||||
index := dq.write & dq.mask
|
||||
t := dq.types[index]
|
||||
dq.types[index] = nil
|
||||
return t
|
||||
}
|
||||
|
||||
// all returns all elements.
|
||||
//
|
||||
// The deque is empty after calling this method.
|
||||
func (dq *typeDeque) all() []*Type {
|
||||
length := dq.write - dq.read
|
||||
types := make([]*Type, 0, length)
|
||||
for t := dq.shift(); t != nil; t = dq.shift() {
|
||||
types = append(types, t)
|
||||
}
|
||||
return types
|
||||
}
|
||||
|
||||
// inflateRawTypes takes a list of raw btf types linked via type IDs, and turns
|
||||
// it into a graph of Types connected via pointers.
|
||||
//
|
||||
// Returns a map of named types (so, where NameOff is non-zero) and a slice of types
|
||||
// indexed by TypeID. Since BTF ignores compilation units, multiple types may share
|
||||
// the same name. A Type may form a cyclic graph by pointing at itself.
|
||||
func inflateRawTypes(rawTypes []rawType, rawStrings stringTable) (types []Type, namedTypes map[string][]namedType, err error) {
|
||||
type fixupDef struct {
|
||||
id TypeID
|
||||
expectedKind btfKind
|
||||
typ *Type
|
||||
}
|
||||
|
||||
var fixups []fixupDef
|
||||
fixup := func(id TypeID, expectedKind btfKind, typ *Type) {
|
||||
fixups = append(fixups, fixupDef{id, expectedKind, typ})
|
||||
}
|
||||
|
||||
convertMembers := func(raw []btfMember, kindFlag bool) ([]Member, error) {
|
||||
// NB: The fixup below relies on pre-allocating this array to
|
||||
// work, since otherwise append might re-allocate members.
|
||||
members := make([]Member, 0, len(raw))
|
||||
for i, btfMember := range raw {
|
||||
name, err := rawStrings.LookupName(btfMember.NameOff)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("can't get name for member %d: %w", i, err)
|
||||
}
|
||||
m := Member{
|
||||
Name: name,
|
||||
Offset: btfMember.Offset,
|
||||
}
|
||||
if kindFlag {
|
||||
m.BitfieldSize = btfMember.Offset >> 24
|
||||
m.Offset &= 0xffffff
|
||||
}
|
||||
members = append(members, m)
|
||||
}
|
||||
for i := range members {
|
||||
fixup(raw[i].Type, kindUnknown, &members[i].Type)
|
||||
}
|
||||
return members, nil
|
||||
}
|
||||
|
||||
types = make([]Type, 0, len(rawTypes))
|
||||
types = append(types, (*Void)(nil))
|
||||
namedTypes = make(map[string][]namedType)
|
||||
|
||||
for i, raw := range rawTypes {
|
||||
var (
|
||||
// Void is defined to always be type ID 0, and is thus
|
||||
// omitted from BTF.
|
||||
id = TypeID(i + 1)
|
||||
typ Type
|
||||
)
|
||||
|
||||
name, err := rawStrings.LookupName(raw.NameOff)
|
||||
if err != nil {
|
||||
return nil, nil, fmt.Errorf("get name for type id %d: %w", id, err)
|
||||
}
|
||||
|
||||
switch raw.Kind() {
|
||||
case kindInt:
|
||||
encoding, offset, bits := intEncoding(*raw.data.(*uint32))
|
||||
typ = &Int{id, name, raw.Size(), encoding, offset, bits}
|
||||
|
||||
case kindPointer:
|
||||
ptr := &Pointer{id, nil}
|
||||
fixup(raw.Type(), kindUnknown, &ptr.Target)
|
||||
typ = ptr
|
||||
|
||||
case kindArray:
|
||||
btfArr := raw.data.(*btfArray)
|
||||
|
||||
// IndexType is unused according to btf.rst.
|
||||
// Don't make it available right now.
|
||||
arr := &Array{id, nil, btfArr.Nelems}
|
||||
fixup(btfArr.Type, kindUnknown, &arr.Type)
|
||||
typ = arr
|
||||
|
||||
case kindStruct:
|
||||
members, err := convertMembers(raw.data.([]btfMember), raw.KindFlag())
|
||||
if err != nil {
|
||||
return nil, nil, fmt.Errorf("struct %s (id %d): %w", name, id, err)
|
||||
}
|
||||
typ = &Struct{id, name, raw.Size(), members}
|
||||
|
||||
case kindUnion:
|
||||
members, err := convertMembers(raw.data.([]btfMember), raw.KindFlag())
|
||||
if err != nil {
|
||||
return nil, nil, fmt.Errorf("union %s (id %d): %w", name, id, err)
|
||||
}
|
||||
typ = &Union{id, name, raw.Size(), members}
|
||||
|
||||
case kindEnum:
|
||||
rawvals := raw.data.([]btfEnum)
|
||||
vals := make([]EnumValue, 0, len(rawvals))
|
||||
for i, btfVal := range rawvals {
|
||||
name, err := rawStrings.LookupName(btfVal.NameOff)
|
||||
if err != nil {
|
||||
return nil, nil, fmt.Errorf("get name for enum value %d: %s", i, err)
|
||||
}
|
||||
vals = append(vals, EnumValue{
|
||||
Name: name,
|
||||
Value: btfVal.Val,
|
||||
})
|
||||
}
|
||||
typ = &Enum{id, name, vals}
|
||||
|
||||
case kindForward:
|
||||
if raw.KindFlag() {
|
||||
typ = &Fwd{id, name, FwdUnion}
|
||||
} else {
|
||||
typ = &Fwd{id, name, FwdStruct}
|
||||
}
|
||||
|
||||
case kindTypedef:
|
||||
typedef := &Typedef{id, name, nil}
|
||||
fixup(raw.Type(), kindUnknown, &typedef.Type)
|
||||
typ = typedef
|
||||
|
||||
case kindVolatile:
|
||||
volatile := &Volatile{id, nil}
|
||||
fixup(raw.Type(), kindUnknown, &volatile.Type)
|
||||
typ = volatile
|
||||
|
||||
case kindConst:
|
||||
cnst := &Const{id, nil}
|
||||
fixup(raw.Type(), kindUnknown, &cnst.Type)
|
||||
typ = cnst
|
||||
|
||||
case kindRestrict:
|
||||
restrict := &Restrict{id, nil}
|
||||
fixup(raw.Type(), kindUnknown, &restrict.Type)
|
||||
typ = restrict
|
||||
|
||||
case kindFunc:
|
||||
fn := &Func{id, name, nil}
|
||||
fixup(raw.Type(), kindFuncProto, &fn.Type)
|
||||
typ = fn
|
||||
|
||||
case kindFuncProto:
|
||||
rawparams := raw.data.([]btfParam)
|
||||
params := make([]FuncParam, 0, len(rawparams))
|
||||
for i, param := range rawparams {
|
||||
name, err := rawStrings.LookupName(param.NameOff)
|
||||
if err != nil {
|
||||
return nil, nil, fmt.Errorf("get name for func proto parameter %d: %s", i, err)
|
||||
}
|
||||
params = append(params, FuncParam{
|
||||
Name: name,
|
||||
})
|
||||
}
|
||||
for i := range params {
|
||||
fixup(rawparams[i].Type, kindUnknown, ¶ms[i].Type)
|
||||
}
|
||||
|
||||
fp := &FuncProto{id, nil, params}
|
||||
fixup(raw.Type(), kindUnknown, &fp.Return)
|
||||
typ = fp
|
||||
|
||||
case kindVar:
|
||||
v := &Var{id, name, nil}
|
||||
fixup(raw.Type(), kindUnknown, &v.Type)
|
||||
typ = v
|
||||
|
||||
case kindDatasec:
|
||||
btfVars := raw.data.([]btfVarSecinfo)
|
||||
vars := make([]VarSecinfo, 0, len(btfVars))
|
||||
for _, btfVar := range btfVars {
|
||||
vars = append(vars, VarSecinfo{
|
||||
Offset: btfVar.Offset,
|
||||
Size: btfVar.Size,
|
||||
})
|
||||
}
|
||||
for i := range vars {
|
||||
fixup(btfVars[i].Type, kindVar, &vars[i].Type)
|
||||
}
|
||||
typ = &Datasec{id, name, raw.SizeType, vars}
|
||||
|
||||
default:
|
||||
return nil, nil, fmt.Errorf("type id %d: unknown kind: %v", id, raw.Kind())
|
||||
}
|
||||
|
||||
types = append(types, typ)
|
||||
|
||||
if named, ok := typ.(namedType); ok {
|
||||
if name := essentialName(named.name()); name != "" {
|
||||
namedTypes[name] = append(namedTypes[name], named)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
for _, fixup := range fixups {
|
||||
i := int(fixup.id)
|
||||
if i >= len(types) {
|
||||
return nil, nil, fmt.Errorf("reference to invalid type id: %d", fixup.id)
|
||||
}
|
||||
|
||||
// Default void (id 0) to unknown
|
||||
rawKind := kindUnknown
|
||||
if i > 0 {
|
||||
rawKind = rawTypes[i-1].Kind()
|
||||
}
|
||||
|
||||
if expected := fixup.expectedKind; expected != kindUnknown && rawKind != expected {
|
||||
return nil, nil, fmt.Errorf("expected type id %d to have kind %s, found %s", fixup.id, expected, rawKind)
|
||||
}
|
||||
|
||||
*fixup.typ = types[i]
|
||||
}
|
||||
|
||||
return types, namedTypes, nil
|
||||
}
|
||||
|
||||
// essentialName returns name without a ___ suffix.
|
||||
func essentialName(name string) string {
|
||||
lastIdx := strings.LastIndex(name, "___")
|
||||
if lastIdx > 0 {
|
||||
return name[:lastIdx]
|
||||
}
|
||||
return name
|
||||
}
|
|
@ -2,7 +2,7 @@ package internal
|
|||
|
||||
import (
|
||||
"fmt"
|
||||
"io/ioutil"
|
||||
"os"
|
||||
"strings"
|
||||
"sync"
|
||||
)
|
||||
|
@ -24,7 +24,7 @@ func PossibleCPUs() (int, error) {
|
|||
}
|
||||
|
||||
func parseCPUsFromFile(path string) (int, error) {
|
||||
spec, err := ioutil.ReadFile(path)
|
||||
spec, err := os.ReadFile(path)
|
||||
if err != nil {
|
||||
return 0, err
|
||||
}
|
||||
|
|
|
@ -35,6 +35,29 @@ func NewSafeELFFile(r io.ReaderAt) (safe *SafeELFFile, err error) {
|
|||
return &SafeELFFile{file}, nil
|
||||
}
|
||||
|
||||
// OpenSafeELFFile reads an ELF from a file.
|
||||
//
|
||||
// It works like NewSafeELFFile, with the exception that safe.Close will
|
||||
// close the underlying file.
|
||||
func OpenSafeELFFile(path string) (safe *SafeELFFile, err error) {
|
||||
defer func() {
|
||||
r := recover()
|
||||
if r == nil {
|
||||
return
|
||||
}
|
||||
|
||||
safe = nil
|
||||
err = fmt.Errorf("reading ELF file panicked: %s", r)
|
||||
}()
|
||||
|
||||
file, err := elf.Open(path)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return &SafeELFFile{file}, nil
|
||||
}
|
||||
|
||||
// Symbols is the safe version of elf.File.Symbols.
|
||||
func (se *SafeELFFile) Symbols() (syms []elf.Symbol, err error) {
|
||||
defer func() {
|
||||
|
@ -50,3 +73,30 @@ func (se *SafeELFFile) Symbols() (syms []elf.Symbol, err error) {
|
|||
syms, err = se.File.Symbols()
|
||||
return
|
||||
}
|
||||
|
||||
// DynamicSymbols is the safe version of elf.File.DynamicSymbols.
|
||||
func (se *SafeELFFile) DynamicSymbols() (syms []elf.Symbol, err error) {
|
||||
defer func() {
|
||||
r := recover()
|
||||
if r == nil {
|
||||
return
|
||||
}
|
||||
|
||||
syms = nil
|
||||
err = fmt.Errorf("reading ELF dynamic symbols panicked: %s", r)
|
||||
}()
|
||||
|
||||
syms, err = se.File.DynamicSymbols()
|
||||
return
|
||||
}
|
||||
|
||||
// SectionsByType returns all sections in the file with the specified section type.
|
||||
func (se *SafeELFFile) SectionsByType(typ elf.SectionType) []*elf.Section {
|
||||
sections := make([]*elf.Section, 0, 1)
|
||||
for _, section := range se.Sections {
|
||||
if section.Type == typ {
|
||||
sections = append(sections, section)
|
||||
}
|
||||
}
|
||||
return sections
|
||||
}
|
||||
|
|
|
@ -1,24 +0,0 @@
|
|||
package internal
|
||||
|
||||
import (
|
||||
"encoding/binary"
|
||||
"unsafe"
|
||||
)
|
||||
|
||||
// NativeEndian is set to either binary.BigEndian or binary.LittleEndian,
|
||||
// depending on the host's endianness.
|
||||
var NativeEndian binary.ByteOrder
|
||||
|
||||
func init() {
|
||||
if isBigEndian() {
|
||||
NativeEndian = binary.BigEndian
|
||||
} else {
|
||||
NativeEndian = binary.LittleEndian
|
||||
}
|
||||
}
|
||||
|
||||
func isBigEndian() (ret bool) {
|
||||
i := int(0x1)
|
||||
bs := (*[int(unsafe.Sizeof(i))]byte)(unsafe.Pointer(&i))
|
||||
return bs[0] == 0
|
||||
}
|
|
@ -0,0 +1,13 @@
|
|||
//go:build armbe || arm64be || mips || mips64 || mips64p32 || ppc64 || s390 || s390x || sparc || sparc64
|
||||
// +build armbe arm64be mips mips64 mips64p32 ppc64 s390 s390x sparc sparc64
|
||||
|
||||
package internal
|
||||
|
||||
import "encoding/binary"
|
||||
|
||||
// NativeEndian is set to either binary.BigEndian or binary.LittleEndian,
|
||||
// depending on the host's endianness.
|
||||
var NativeEndian binary.ByteOrder = binary.BigEndian
|
||||
|
||||
// ClangEndian is set to either "el" or "eb" depending on the host's endianness.
|
||||
const ClangEndian = "eb"
|
|
@ -0,0 +1,13 @@
|
|||
//go:build 386 || amd64 || amd64p32 || arm || arm64 || mipsle || mips64le || mips64p32le || ppc64le || riscv64
|
||||
// +build 386 amd64 amd64p32 arm arm64 mipsle mips64le mips64p32le ppc64le riscv64
|
||||
|
||||
package internal
|
||||
|
||||
import "encoding/binary"
|
||||
|
||||
// NativeEndian is set to either binary.BigEndian or binary.LittleEndian,
|
||||
// depending on the host's endianness.
|
||||
var NativeEndian binary.ByteOrder = binary.LittleEndian
|
||||
|
||||
// ClangEndian is set to either "el" or "eb" depending on the host's endianness.
|
||||
const ClangEndian = "el"
|
|
@ -2,46 +2,205 @@ package internal
|
|||
|
||||
import (
|
||||
"bytes"
|
||||
"errors"
|
||||
"fmt"
|
||||
"io"
|
||||
"strings"
|
||||
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
// ErrorWithLog returns an error that includes logs from the
|
||||
// kernel verifier.
|
||||
// ErrorWithLog returns an error which includes logs from the kernel verifier.
|
||||
//
|
||||
// logErr should be the error returned by the syscall that generated
|
||||
// the log. It is used to check for truncation of the output.
|
||||
func ErrorWithLog(err error, log []byte, logErr error) error {
|
||||
logStr := strings.Trim(CString(log), "\t\r\n ")
|
||||
if errors.Is(logErr, unix.ENOSPC) {
|
||||
logStr += " (truncated...)"
|
||||
// The default error output is a summary of the full log. The latter can be
|
||||
// accessed via VerifierError.Log or by formatting the error, see Format.
|
||||
//
|
||||
// A set of heuristics is used to determine whether the log has been truncated.
|
||||
func ErrorWithLog(err error, log []byte) *VerifierError {
|
||||
const whitespace = "\t\r\v\n "
|
||||
|
||||
// Convert verifier log C string by truncating it on the first 0 byte
|
||||
// and trimming trailing whitespace before interpreting as a Go string.
|
||||
truncated := false
|
||||
if i := bytes.IndexByte(log, 0); i != -1 {
|
||||
if i == len(log)-1 && !bytes.HasSuffix(log[:i], []byte{'\n'}) {
|
||||
// The null byte is at the end of the buffer and it's not preceded
|
||||
// by a newline character. Most likely the buffer was too short.
|
||||
truncated = true
|
||||
}
|
||||
|
||||
return &VerifierError{err, logStr}
|
||||
log = log[:i]
|
||||
} else if len(log) > 0 {
|
||||
// No null byte? Dodgy!
|
||||
truncated = true
|
||||
}
|
||||
|
||||
log = bytes.Trim(log, whitespace)
|
||||
logLines := bytes.Split(log, []byte{'\n'})
|
||||
lines := make([]string, 0, len(logLines))
|
||||
for _, line := range logLines {
|
||||
// Don't remove leading white space on individual lines. We rely on it
|
||||
// when outputting logs.
|
||||
lines = append(lines, string(bytes.TrimRight(line, whitespace)))
|
||||
}
|
||||
|
||||
return &VerifierError{err, lines, truncated}
|
||||
}
|
||||
|
||||
// VerifierError includes information from the eBPF verifier.
|
||||
//
|
||||
// It summarises the log output, see Format if you want to output the full contents.
|
||||
type VerifierError struct {
|
||||
cause error
|
||||
log string
|
||||
// The error which caused this error.
|
||||
Cause error
|
||||
// The verifier output split into lines.
|
||||
Log []string
|
||||
// Whether the log output is truncated, based on several heuristics.
|
||||
Truncated bool
|
||||
}
|
||||
|
||||
func (le *VerifierError) Unwrap() error {
|
||||
return le.Cause
|
||||
}
|
||||
|
||||
func (le *VerifierError) Error() string {
|
||||
if le.log == "" {
|
||||
return le.cause.Error()
|
||||
log := le.Log
|
||||
if n := len(log); n > 0 && strings.HasPrefix(log[n-1], "processed ") {
|
||||
// Get rid of "processed 39 insns (limit 1000000) ..." from summary.
|
||||
log = log[:n-1]
|
||||
}
|
||||
|
||||
return fmt.Sprintf("%s: %s", le.cause, le.log)
|
||||
n := len(log)
|
||||
if n == 0 {
|
||||
return le.Cause.Error()
|
||||
}
|
||||
|
||||
// CString turns a NUL / zero terminated byte buffer into a string.
|
||||
func CString(in []byte) string {
|
||||
inLen := bytes.IndexByte(in, 0)
|
||||
if inLen == -1 {
|
||||
return ""
|
||||
lines := log[n-1:]
|
||||
if n >= 2 && (includePreviousLine(log[n-1]) || le.Truncated) {
|
||||
// Add one more line of context if it aids understanding the error.
|
||||
lines = log[n-2:]
|
||||
}
|
||||
|
||||
var b strings.Builder
|
||||
fmt.Fprintf(&b, "%s: ", le.Cause.Error())
|
||||
|
||||
for i, line := range lines {
|
||||
b.WriteString(strings.TrimSpace(line))
|
||||
if i != len(lines)-1 {
|
||||
b.WriteString(": ")
|
||||
}
|
||||
}
|
||||
|
||||
omitted := len(le.Log) - len(lines)
|
||||
if omitted == 0 && !le.Truncated {
|
||||
return b.String()
|
||||
}
|
||||
|
||||
b.WriteString(" (")
|
||||
if le.Truncated {
|
||||
b.WriteString("truncated")
|
||||
}
|
||||
|
||||
if omitted > 0 {
|
||||
if le.Truncated {
|
||||
b.WriteString(", ")
|
||||
}
|
||||
fmt.Fprintf(&b, "%d line(s) omitted", omitted)
|
||||
}
|
||||
b.WriteString(")")
|
||||
|
||||
return b.String()
|
||||
}
|
||||
|
||||
// includePreviousLine returns true if the given line likely is better
|
||||
// understood with additional context from the preceding line.
|
||||
func includePreviousLine(line string) bool {
|
||||
// We need to find a good trade off between understandable error messages
|
||||
// and too much complexity here. Checking the string prefix is ok, requiring
|
||||
// regular expressions to do it is probably overkill.
|
||||
|
||||
if strings.HasPrefix(line, "\t") {
|
||||
// [13] STRUCT drm_rect size=16 vlen=4
|
||||
// \tx1 type_id=2
|
||||
return true
|
||||
}
|
||||
|
||||
if len(line) >= 2 && line[0] == 'R' && line[1] >= '0' && line[1] <= '9' {
|
||||
// 0: (95) exit
|
||||
// R0 !read_ok
|
||||
return true
|
||||
}
|
||||
|
||||
if strings.HasPrefix(line, "invalid bpf_context access") {
|
||||
// 0: (79) r6 = *(u64 *)(r1 +0)
|
||||
// func '__x64_sys_recvfrom' arg0 type FWD is not a struct
|
||||
// invalid bpf_context access off=0 size=8
|
||||
return true
|
||||
}
|
||||
|
||||
return false
|
||||
}
|
||||
|
||||
// Format the error.
|
||||
//
|
||||
// Understood verbs are %s and %v, which are equivalent to calling Error(). %v
|
||||
// allows outputting additional information using the following flags:
|
||||
//
|
||||
// + Output the first <width> lines, or all lines if no width is given.
|
||||
// - Output the last <width> lines, or all lines if no width is given.
|
||||
//
|
||||
// Use width to specify how many lines to output. Use the '-' flag to output
|
||||
// lines from the end of the log instead of the beginning.
|
||||
func (le *VerifierError) Format(f fmt.State, verb rune) {
|
||||
switch verb {
|
||||
case 's':
|
||||
_, _ = io.WriteString(f, le.Error())
|
||||
|
||||
case 'v':
|
||||
n, haveWidth := f.Width()
|
||||
if !haveWidth || n > len(le.Log) {
|
||||
n = len(le.Log)
|
||||
}
|
||||
|
||||
if !f.Flag('+') && !f.Flag('-') {
|
||||
if haveWidth {
|
||||
_, _ = io.WriteString(f, "%!v(BADWIDTH)")
|
||||
return
|
||||
}
|
||||
|
||||
_, _ = io.WriteString(f, le.Error())
|
||||
return
|
||||
}
|
||||
|
||||
if f.Flag('+') && f.Flag('-') {
|
||||
_, _ = io.WriteString(f, "%!v(BADFLAG)")
|
||||
return
|
||||
}
|
||||
|
||||
fmt.Fprintf(f, "%s:", le.Cause.Error())
|
||||
|
||||
omitted := len(le.Log) - n
|
||||
lines := le.Log[:n]
|
||||
if f.Flag('-') {
|
||||
// Print last instead of first lines.
|
||||
lines = le.Log[len(le.Log)-n:]
|
||||
if omitted > 0 {
|
||||
fmt.Fprintf(f, "\n\t(%d line(s) omitted)", omitted)
|
||||
}
|
||||
}
|
||||
|
||||
for _, line := range lines {
|
||||
fmt.Fprintf(f, "\n\t%s", line)
|
||||
}
|
||||
|
||||
if !f.Flag('-') {
|
||||
if omitted > 0 {
|
||||
fmt.Fprintf(f, "\n\t(%d line(s) omitted)", omitted)
|
||||
}
|
||||
}
|
||||
|
||||
if le.Truncated {
|
||||
fmt.Fprintf(f, "\n\t(truncated)")
|
||||
}
|
||||
|
||||
default:
|
||||
fmt.Fprintf(f, "%%!%c(BADVERB)", verb)
|
||||
}
|
||||
return string(in[:inLen])
|
||||
}
|
||||
|
|
|
@ -1,69 +0,0 @@
|
|||
package internal
|
||||
|
||||
import (
|
||||
"errors"
|
||||
"fmt"
|
||||
"os"
|
||||
"runtime"
|
||||
"strconv"
|
||||
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
var ErrClosedFd = errors.New("use of closed file descriptor")
|
||||
|
||||
type FD struct {
|
||||
raw int64
|
||||
}
|
||||
|
||||
func NewFD(value uint32) *FD {
|
||||
fd := &FD{int64(value)}
|
||||
runtime.SetFinalizer(fd, (*FD).Close)
|
||||
return fd
|
||||
}
|
||||
|
||||
func (fd *FD) String() string {
|
||||
return strconv.FormatInt(fd.raw, 10)
|
||||
}
|
||||
|
||||
func (fd *FD) Value() (uint32, error) {
|
||||
if fd.raw < 0 {
|
||||
return 0, ErrClosedFd
|
||||
}
|
||||
|
||||
return uint32(fd.raw), nil
|
||||
}
|
||||
|
||||
func (fd *FD) Close() error {
|
||||
if fd.raw < 0 {
|
||||
return nil
|
||||
}
|
||||
|
||||
value := int(fd.raw)
|
||||
fd.raw = -1
|
||||
|
||||
fd.Forget()
|
||||
return unix.Close(value)
|
||||
}
|
||||
|
||||
func (fd *FD) Forget() {
|
||||
runtime.SetFinalizer(fd, nil)
|
||||
}
|
||||
|
||||
func (fd *FD) Dup() (*FD, error) {
|
||||
if fd.raw < 0 {
|
||||
return nil, ErrClosedFd
|
||||
}
|
||||
|
||||
dup, err := unix.FcntlInt(uintptr(fd.raw), unix.F_DUPFD_CLOEXEC, 0)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("can't dup fd: %v", err)
|
||||
}
|
||||
|
||||
return NewFD(uint32(dup)), nil
|
||||
}
|
||||
|
||||
func (fd *FD) File(name string) *os.File {
|
||||
fd.Forget()
|
||||
return os.NewFile(uintptr(fd.raw), name)
|
||||
}
|
|
@ -54,11 +54,6 @@ type FeatureTestFn func() error
|
|||
//
|
||||
// Returns an error wrapping ErrNotSupported if the feature is not supported.
|
||||
func FeatureTest(name, version string, fn FeatureTestFn) func() error {
|
||||
v, err := NewVersion(version)
|
||||
if err != nil {
|
||||
return func() error { return err }
|
||||
}
|
||||
|
||||
ft := new(featureTest)
|
||||
return func() error {
|
||||
ft.RLock()
|
||||
|
@ -79,6 +74,11 @@ func FeatureTest(name, version string, fn FeatureTestFn) func() error {
|
|||
err := fn()
|
||||
switch {
|
||||
case errors.Is(err, ErrNotSupported):
|
||||
v, err := NewVersion(version)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
ft.result = &UnsupportedFeatureError{
|
||||
MinimumVersion: v,
|
||||
Name: name,
|
||||
|
@ -98,41 +98,3 @@ func FeatureTest(name, version string, fn FeatureTestFn) func() error {
|
|||
return ft.result
|
||||
}
|
||||
}
|
||||
|
||||
// A Version in the form Major.Minor.Patch.
|
||||
type Version [3]uint16
|
||||
|
||||
// NewVersion creates a version from a string like "Major.Minor.Patch".
|
||||
//
|
||||
// Patch is optional.
|
||||
func NewVersion(ver string) (Version, error) {
|
||||
var major, minor, patch uint16
|
||||
n, _ := fmt.Sscanf(ver, "%d.%d.%d", &major, &minor, &patch)
|
||||
if n < 2 {
|
||||
return Version{}, fmt.Errorf("invalid version: %s", ver)
|
||||
}
|
||||
return Version{major, minor, patch}, nil
|
||||
}
|
||||
|
||||
func (v Version) String() string {
|
||||
if v[2] == 0 {
|
||||
return fmt.Sprintf("v%d.%d", v[0], v[1])
|
||||
}
|
||||
return fmt.Sprintf("v%d.%d.%d", v[0], v[1], v[2])
|
||||
}
|
||||
|
||||
// Less returns true if the version is less than another version.
|
||||
func (v Version) Less(other Version) bool {
|
||||
for i, a := range v {
|
||||
if a == other[i] {
|
||||
continue
|
||||
}
|
||||
return a < other[i]
|
||||
}
|
||||
return false
|
||||
}
|
||||
|
||||
// Unspecified returns true if the version is all zero.
|
||||
func (v Version) Unspecified() bool {
|
||||
return v[0] == 0 && v[1] == 0 && v[2] == 0
|
||||
}
|
||||
|
|
|
@ -1,6 +1,35 @@
|
|||
package internal
|
||||
|
||||
import "errors"
|
||||
import (
|
||||
"bufio"
|
||||
"compress/gzip"
|
||||
"errors"
|
||||
"io"
|
||||
"os"
|
||||
)
|
||||
|
||||
// NewBufferedSectionReader wraps an io.ReaderAt in an appropriately-sized
|
||||
// buffered reader. It is a convenience function for reading subsections of
|
||||
// ELF sections while minimizing the amount of read() syscalls made.
|
||||
//
|
||||
// Syscall overhead is non-negligible in continuous integration context
|
||||
// where ELFs might be accessed over virtual filesystems with poor random
|
||||
// access performance. Buffering reads makes sense because (sub)sections
|
||||
// end up being read completely anyway.
|
||||
//
|
||||
// Use instead of the r.Seek() + io.LimitReader() pattern.
|
||||
func NewBufferedSectionReader(ra io.ReaderAt, off, n int64) *bufio.Reader {
|
||||
// Clamp the size of the buffer to one page to avoid slurping large parts
|
||||
// of a file into memory. bufio.NewReader uses a hardcoded default buffer
|
||||
// of 4096. Allow arches with larger pages to allocate more, but don't
|
||||
// allocate a fixed 4k buffer if we only need to read a small segment.
|
||||
buf := n
|
||||
if ps := int64(os.Getpagesize()); n > ps {
|
||||
buf = ps
|
||||
}
|
||||
|
||||
return bufio.NewReaderSize(io.NewSectionReader(ra, off, n), int(buf))
|
||||
}
|
||||
|
||||
// DiscardZeroes makes sure that all written bytes are zero
|
||||
// before discarding them.
|
||||
|
@ -14,3 +43,20 @@ func (DiscardZeroes) Write(p []byte) (int, error) {
|
|||
}
|
||||
return len(p), nil
|
||||
}
|
||||
|
||||
// ReadAllCompressed decompresses a gzipped file into memory.
|
||||
func ReadAllCompressed(file string) ([]byte, error) {
|
||||
fh, err := os.Open(file)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
defer fh.Close()
|
||||
|
||||
gz, err := gzip.NewReader(fh)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
defer gz.Close()
|
||||
|
||||
return io.ReadAll(gz)
|
||||
}
|
||||
|
|
|
@ -0,0 +1,84 @@
|
|||
package internal
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"errors"
|
||||
"go/format"
|
||||
"go/scanner"
|
||||
"io"
|
||||
"strings"
|
||||
"unicode"
|
||||
)
|
||||
|
||||
// Identifier turns a C style type or field name into an exportable Go equivalent.
|
||||
func Identifier(str string) string {
|
||||
prev := rune(-1)
|
||||
return strings.Map(func(r rune) rune {
|
||||
// See https://golang.org/ref/spec#Identifiers
|
||||
switch {
|
||||
case unicode.IsLetter(r):
|
||||
if prev == -1 {
|
||||
r = unicode.ToUpper(r)
|
||||
}
|
||||
|
||||
case r == '_':
|
||||
switch {
|
||||
// The previous rune was deleted, or we are at the
|
||||
// beginning of the string.
|
||||
case prev == -1:
|
||||
fallthrough
|
||||
|
||||
// The previous rune is a lower case letter or a digit.
|
||||
case unicode.IsDigit(prev) || (unicode.IsLetter(prev) && unicode.IsLower(prev)):
|
||||
// delete the current rune, and force the
|
||||
// next character to be uppercased.
|
||||
r = -1
|
||||
}
|
||||
|
||||
case unicode.IsDigit(r):
|
||||
|
||||
default:
|
||||
// Delete the current rune. prev is unchanged.
|
||||
return -1
|
||||
}
|
||||
|
||||
prev = r
|
||||
return r
|
||||
}, str)
|
||||
}
|
||||
|
||||
// WriteFormatted outputs a formatted src into out.
|
||||
//
|
||||
// If formatting fails it returns an informative error message.
|
||||
func WriteFormatted(src []byte, out io.Writer) error {
|
||||
formatted, err := format.Source(src)
|
||||
if err == nil {
|
||||
_, err = out.Write(formatted)
|
||||
return err
|
||||
}
|
||||
|
||||
var el scanner.ErrorList
|
||||
if !errors.As(err, &el) {
|
||||
return err
|
||||
}
|
||||
|
||||
var nel scanner.ErrorList
|
||||
for _, err := range el {
|
||||
if !err.Pos.IsValid() {
|
||||
nel = append(nel, err)
|
||||
continue
|
||||
}
|
||||
|
||||
buf := src[err.Pos.Offset:]
|
||||
nl := bytes.IndexRune(buf, '\n')
|
||||
if nl == -1 {
|
||||
nel = append(nel, err)
|
||||
continue
|
||||
}
|
||||
|
||||
err.Msg += ": " + string(buf[:nl])
|
||||
nel = append(nel, err)
|
||||
}
|
||||
|
||||
return nel
|
||||
}
|
|
@ -0,0 +1,77 @@
|
|||
package internal
|
||||
|
||||
import (
|
||||
"errors"
|
||||
"fmt"
|
||||
"os"
|
||||
"path/filepath"
|
||||
"runtime"
|
||||
"unsafe"
|
||||
|
||||
"github.com/cilium/ebpf/internal/sys"
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
func Pin(currentPath, newPath string, fd *sys.FD) error {
|
||||
const bpfFSType = 0xcafe4a11
|
||||
|
||||
if newPath == "" {
|
||||
return errors.New("given pinning path cannot be empty")
|
||||
}
|
||||
if currentPath == newPath {
|
||||
return nil
|
||||
}
|
||||
|
||||
var statfs unix.Statfs_t
|
||||
if err := unix.Statfs(filepath.Dir(newPath), &statfs); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
fsType := int64(statfs.Type)
|
||||
if unsafe.Sizeof(statfs.Type) == 4 {
|
||||
// We're on a 32 bit arch, where statfs.Type is int32. bpfFSType is a
|
||||
// negative number when interpreted as int32 so we need to cast via
|
||||
// uint32 to avoid sign extension.
|
||||
fsType = int64(uint32(statfs.Type))
|
||||
}
|
||||
|
||||
if fsType != bpfFSType {
|
||||
return fmt.Errorf("%s is not on a bpf filesystem", newPath)
|
||||
}
|
||||
|
||||
defer runtime.KeepAlive(fd)
|
||||
|
||||
if currentPath == "" {
|
||||
return sys.ObjPin(&sys.ObjPinAttr{
|
||||
Pathname: sys.NewStringPointer(newPath),
|
||||
BpfFd: fd.Uint(),
|
||||
})
|
||||
}
|
||||
|
||||
// Renameat2 is used instead of os.Rename to disallow the new path replacing
|
||||
// an existing path.
|
||||
err := unix.Renameat2(unix.AT_FDCWD, currentPath, unix.AT_FDCWD, newPath, unix.RENAME_NOREPLACE)
|
||||
if err == nil {
|
||||
// Object is now moved to the new pinning path.
|
||||
return nil
|
||||
}
|
||||
if !os.IsNotExist(err) {
|
||||
return fmt.Errorf("unable to move pinned object to new path %v: %w", newPath, err)
|
||||
}
|
||||
// Internal state not in sync with the file system so let's fix it.
|
||||
return sys.ObjPin(&sys.ObjPinAttr{
|
||||
Pathname: sys.NewStringPointer(newPath),
|
||||
BpfFd: fd.Uint(),
|
||||
})
|
||||
}
|
||||
|
||||
func Unpin(pinnedPath string) error {
|
||||
if pinnedPath == "" {
|
||||
return nil
|
||||
}
|
||||
err := os.Remove(pinnedPath)
|
||||
if err == nil || os.IsNotExist(err) {
|
||||
return nil
|
||||
}
|
||||
return err
|
||||
}
|
|
@ -1,14 +0,0 @@
|
|||
// +build !386,!amd64p32,!arm,!mipsle,!mips64p32le
|
||||
// +build !armbe,!mips,!mips64p32
|
||||
|
||||
package internal
|
||||
|
||||
import (
|
||||
"unsafe"
|
||||
)
|
||||
|
||||
// Pointer wraps an unsafe.Pointer to be 64bit to
|
||||
// conform to the syscall specification.
|
||||
type Pointer struct {
|
||||
ptr unsafe.Pointer
|
||||
}
|
|
@ -0,0 +1,6 @@
|
|||
// Package sys contains bindings for the BPF syscall.
|
||||
package sys
|
||||
|
||||
// Regenerate types.go by invoking go generate in the current directory.
|
||||
|
||||
//go:generate go run github.com/cilium/ebpf/internal/cmd/gentypes ../../btf/testdata/vmlinux.btf.gz
|
|
@ -0,0 +1,96 @@
|
|||
package sys
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
"math"
|
||||
"os"
|
||||
"runtime"
|
||||
"strconv"
|
||||
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
var ErrClosedFd = unix.EBADF
|
||||
|
||||
type FD struct {
|
||||
raw int
|
||||
}
|
||||
|
||||
func newFD(value int) *FD {
|
||||
fd := &FD{value}
|
||||
runtime.SetFinalizer(fd, (*FD).Close)
|
||||
return fd
|
||||
}
|
||||
|
||||
// NewFD wraps a raw fd with a finalizer.
|
||||
//
|
||||
// You must not use the raw fd after calling this function, since the underlying
|
||||
// file descriptor number may change. This is because the BPF UAPI assumes that
|
||||
// zero is not a valid fd value.
|
||||
func NewFD(value int) (*FD, error) {
|
||||
if value < 0 {
|
||||
return nil, fmt.Errorf("invalid fd %d", value)
|
||||
}
|
||||
|
||||
fd := newFD(value)
|
||||
if value != 0 {
|
||||
return fd, nil
|
||||
}
|
||||
|
||||
dup, err := fd.Dup()
|
||||
_ = fd.Close()
|
||||
return dup, err
|
||||
}
|
||||
|
||||
func (fd *FD) String() string {
|
||||
return strconv.FormatInt(int64(fd.raw), 10)
|
||||
}
|
||||
|
||||
func (fd *FD) Int() int {
|
||||
return fd.raw
|
||||
}
|
||||
|
||||
func (fd *FD) Uint() uint32 {
|
||||
if fd.raw < 0 || int64(fd.raw) > math.MaxUint32 {
|
||||
// Best effort: this is the number most likely to be an invalid file
|
||||
// descriptor. It is equal to -1 (on two's complement arches).
|
||||
return math.MaxUint32
|
||||
}
|
||||
return uint32(fd.raw)
|
||||
}
|
||||
|
||||
func (fd *FD) Close() error {
|
||||
if fd.raw < 0 {
|
||||
return nil
|
||||
}
|
||||
|
||||
value := int(fd.raw)
|
||||
fd.raw = -1
|
||||
|
||||
fd.Forget()
|
||||
return unix.Close(value)
|
||||
}
|
||||
|
||||
func (fd *FD) Forget() {
|
||||
runtime.SetFinalizer(fd, nil)
|
||||
}
|
||||
|
||||
func (fd *FD) Dup() (*FD, error) {
|
||||
if fd.raw < 0 {
|
||||
return nil, ErrClosedFd
|
||||
}
|
||||
|
||||
// Always require the fd to be larger than zero: the BPF API treats the value
|
||||
// as "no argument provided".
|
||||
dup, err := unix.FcntlInt(uintptr(fd.raw), unix.F_DUPFD_CLOEXEC, 1)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("can't dup fd: %v", err)
|
||||
}
|
||||
|
||||
return newFD(dup), nil
|
||||
}
|
||||
|
||||
func (fd *FD) File(name string) *os.File {
|
||||
fd.Forget()
|
||||
return os.NewFile(uintptr(fd.raw), name)
|
||||
}
|
|
@ -1,6 +1,10 @@
|
|||
package internal
|
||||
package sys
|
||||
|
||||
import "unsafe"
|
||||
import (
|
||||
"unsafe"
|
||||
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
// NewPointer creates a 64-bit pointer from an unsafe Pointer.
|
||||
func NewPointer(ptr unsafe.Pointer) Pointer {
|
||||
|
@ -16,15 +20,19 @@ func NewSlicePointer(buf []byte) Pointer {
|
|||
return Pointer{ptr: unsafe.Pointer(&buf[0])}
|
||||
}
|
||||
|
||||
// NewSlicePointer creates a 64-bit pointer from a byte slice.
|
||||
//
|
||||
// Useful to assign both the pointer and the length in one go.
|
||||
func NewSlicePointerLen(buf []byte) (Pointer, uint32) {
|
||||
return NewSlicePointer(buf), uint32(len(buf))
|
||||
}
|
||||
|
||||
// NewStringPointer creates a 64-bit pointer from a string.
|
||||
func NewStringPointer(str string) Pointer {
|
||||
if str == "" {
|
||||
p, err := unix.BytePtrFromString(str)
|
||||
if err != nil {
|
||||
return Pointer{}
|
||||
}
|
||||
|
||||
// The kernel expects strings to be zero terminated
|
||||
buf := make([]byte, len(str)+1)
|
||||
copy(buf, str)
|
||||
|
||||
return Pointer{ptr: unsafe.Pointer(&buf[0])}
|
||||
return Pointer{ptr: unsafe.Pointer(p)}
|
||||
}
|
|
@ -1,6 +1,7 @@
|
|||
//go:build armbe || mips || mips64p32
|
||||
// +build armbe mips mips64p32
|
||||
|
||||
package internal
|
||||
package sys
|
||||
|
||||
import (
|
||||
"unsafe"
|
|
@ -1,6 +1,7 @@
|
|||
//go:build 386 || amd64p32 || arm || mipsle || mips64p32le
|
||||
// +build 386 amd64p32 arm mipsle mips64p32le
|
||||
|
||||
package internal
|
||||
package sys
|
||||
|
||||
import (
|
||||
"unsafe"
|
|
@ -0,0 +1,14 @@
|
|||
//go:build !386 && !amd64p32 && !arm && !mipsle && !mips64p32le && !armbe && !mips && !mips64p32
|
||||
// +build !386,!amd64p32,!arm,!mipsle,!mips64p32le,!armbe,!mips,!mips64p32
|
||||
|
||||
package sys
|
||||
|
||||
import (
|
||||
"unsafe"
|
||||
)
|
||||
|
||||
// Pointer wraps an unsafe.Pointer to be 64bit to
|
||||
// conform to the syscall specification.
|
||||
type Pointer struct {
|
||||
ptr unsafe.Pointer
|
||||
}
|
|
@ -0,0 +1,126 @@
|
|||
package sys
|
||||
|
||||
import (
|
||||
"runtime"
|
||||
"syscall"
|
||||
"unsafe"
|
||||
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
// BPF wraps SYS_BPF.
|
||||
//
|
||||
// Any pointers contained in attr must use the Pointer type from this package.
|
||||
func BPF(cmd Cmd, attr unsafe.Pointer, size uintptr) (uintptr, error) {
|
||||
for {
|
||||
r1, _, errNo := unix.Syscall(unix.SYS_BPF, uintptr(cmd), uintptr(attr), size)
|
||||
runtime.KeepAlive(attr)
|
||||
|
||||
// As of ~4.20 the verifier can be interrupted by a signal,
|
||||
// and returns EAGAIN in that case.
|
||||
if errNo == unix.EAGAIN && cmd == BPF_PROG_LOAD {
|
||||
continue
|
||||
}
|
||||
|
||||
var err error
|
||||
if errNo != 0 {
|
||||
err = wrappedErrno{errNo}
|
||||
}
|
||||
|
||||
return r1, err
|
||||
}
|
||||
}
|
||||
|
||||
// Info is implemented by all structs that can be passed to the ObjInfo syscall.
|
||||
//
|
||||
// MapInfo
|
||||
// ProgInfo
|
||||
// LinkInfo
|
||||
// BtfInfo
|
||||
type Info interface {
|
||||
info() (unsafe.Pointer, uint32)
|
||||
}
|
||||
|
||||
var _ Info = (*MapInfo)(nil)
|
||||
|
||||
func (i *MapInfo) info() (unsafe.Pointer, uint32) {
|
||||
return unsafe.Pointer(i), uint32(unsafe.Sizeof(*i))
|
||||
}
|
||||
|
||||
var _ Info = (*ProgInfo)(nil)
|
||||
|
||||
func (i *ProgInfo) info() (unsafe.Pointer, uint32) {
|
||||
return unsafe.Pointer(i), uint32(unsafe.Sizeof(*i))
|
||||
}
|
||||
|
||||
var _ Info = (*LinkInfo)(nil)
|
||||
|
||||
func (i *LinkInfo) info() (unsafe.Pointer, uint32) {
|
||||
return unsafe.Pointer(i), uint32(unsafe.Sizeof(*i))
|
||||
}
|
||||
|
||||
var _ Info = (*BtfInfo)(nil)
|
||||
|
||||
func (i *BtfInfo) info() (unsafe.Pointer, uint32) {
|
||||
return unsafe.Pointer(i), uint32(unsafe.Sizeof(*i))
|
||||
}
|
||||
|
||||
// ObjInfo retrieves information about a BPF Fd.
|
||||
//
|
||||
// info may be one of MapInfo, ProgInfo, LinkInfo and BtfInfo.
|
||||
func ObjInfo(fd *FD, info Info) error {
|
||||
ptr, len := info.info()
|
||||
err := ObjGetInfoByFd(&ObjGetInfoByFdAttr{
|
||||
BpfFd: fd.Uint(),
|
||||
InfoLen: len,
|
||||
Info: NewPointer(ptr),
|
||||
})
|
||||
runtime.KeepAlive(fd)
|
||||
return err
|
||||
}
|
||||
|
||||
// BPFObjName is a null-terminated string made up of
|
||||
// 'A-Za-z0-9_' characters.
|
||||
type ObjName [unix.BPF_OBJ_NAME_LEN]byte
|
||||
|
||||
// NewObjName truncates the result if it is too long.
|
||||
func NewObjName(name string) ObjName {
|
||||
var result ObjName
|
||||
copy(result[:unix.BPF_OBJ_NAME_LEN-1], name)
|
||||
return result
|
||||
}
|
||||
|
||||
// LinkID uniquely identifies a bpf_link.
|
||||
type LinkID uint32
|
||||
|
||||
// BTFID uniquely identifies a BTF blob loaded into the kernel.
|
||||
type BTFID uint32
|
||||
|
||||
// wrappedErrno wraps syscall.Errno to prevent direct comparisons with
|
||||
// syscall.E* or unix.E* constants.
|
||||
//
|
||||
// You should never export an error of this type.
|
||||
type wrappedErrno struct {
|
||||
syscall.Errno
|
||||
}
|
||||
|
||||
func (we wrappedErrno) Unwrap() error {
|
||||
return we.Errno
|
||||
}
|
||||
|
||||
type syscallError struct {
|
||||
error
|
||||
errno syscall.Errno
|
||||
}
|
||||
|
||||
func Error(err error, errno syscall.Errno) error {
|
||||
return &syscallError{err, errno}
|
||||
}
|
||||
|
||||
func (se *syscallError) Is(target error) bool {
|
||||
return target == se.error
|
||||
}
|
||||
|
||||
func (se *syscallError) Unwrap() error {
|
||||
return se.errno
|
||||
}
|
File diff suppressed because it is too large
Load Diff
|
@ -1,179 +0,0 @@
|
|||
package internal
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
"path/filepath"
|
||||
"runtime"
|
||||
"unsafe"
|
||||
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
//go:generate stringer -output syscall_string.go -type=BPFCmd
|
||||
|
||||
// BPFCmd identifies a subcommand of the bpf syscall.
|
||||
type BPFCmd int
|
||||
|
||||
// Well known BPF commands.
|
||||
const (
|
||||
BPF_MAP_CREATE BPFCmd = iota
|
||||
BPF_MAP_LOOKUP_ELEM
|
||||
BPF_MAP_UPDATE_ELEM
|
||||
BPF_MAP_DELETE_ELEM
|
||||
BPF_MAP_GET_NEXT_KEY
|
||||
BPF_PROG_LOAD
|
||||
BPF_OBJ_PIN
|
||||
BPF_OBJ_GET
|
||||
BPF_PROG_ATTACH
|
||||
BPF_PROG_DETACH
|
||||
BPF_PROG_TEST_RUN
|
||||
BPF_PROG_GET_NEXT_ID
|
||||
BPF_MAP_GET_NEXT_ID
|
||||
BPF_PROG_GET_FD_BY_ID
|
||||
BPF_MAP_GET_FD_BY_ID
|
||||
BPF_OBJ_GET_INFO_BY_FD
|
||||
BPF_PROG_QUERY
|
||||
BPF_RAW_TRACEPOINT_OPEN
|
||||
BPF_BTF_LOAD
|
||||
BPF_BTF_GET_FD_BY_ID
|
||||
BPF_TASK_FD_QUERY
|
||||
BPF_MAP_LOOKUP_AND_DELETE_ELEM
|
||||
BPF_MAP_FREEZE
|
||||
BPF_BTF_GET_NEXT_ID
|
||||
BPF_MAP_LOOKUP_BATCH
|
||||
BPF_MAP_LOOKUP_AND_DELETE_BATCH
|
||||
BPF_MAP_UPDATE_BATCH
|
||||
BPF_MAP_DELETE_BATCH
|
||||
BPF_LINK_CREATE
|
||||
BPF_LINK_UPDATE
|
||||
BPF_LINK_GET_FD_BY_ID
|
||||
BPF_LINK_GET_NEXT_ID
|
||||
BPF_ENABLE_STATS
|
||||
BPF_ITER_CREATE
|
||||
)
|
||||
|
||||
// BPF wraps SYS_BPF.
|
||||
//
|
||||
// Any pointers contained in attr must use the Pointer type from this package.
|
||||
func BPF(cmd BPFCmd, attr unsafe.Pointer, size uintptr) (uintptr, error) {
|
||||
r1, _, errNo := unix.Syscall(unix.SYS_BPF, uintptr(cmd), uintptr(attr), size)
|
||||
runtime.KeepAlive(attr)
|
||||
|
||||
var err error
|
||||
if errNo != 0 {
|
||||
err = errNo
|
||||
}
|
||||
|
||||
return r1, err
|
||||
}
|
||||
|
||||
type BPFProgAttachAttr struct {
|
||||
TargetFd uint32
|
||||
AttachBpfFd uint32
|
||||
AttachType uint32
|
||||
AttachFlags uint32
|
||||
ReplaceBpfFd uint32
|
||||
}
|
||||
|
||||
func BPFProgAttach(attr *BPFProgAttachAttr) error {
|
||||
_, err := BPF(BPF_PROG_ATTACH, unsafe.Pointer(attr), unsafe.Sizeof(*attr))
|
||||
return err
|
||||
}
|
||||
|
||||
type BPFProgDetachAttr struct {
|
||||
TargetFd uint32
|
||||
AttachBpfFd uint32
|
||||
AttachType uint32
|
||||
}
|
||||
|
||||
func BPFProgDetach(attr *BPFProgDetachAttr) error {
|
||||
_, err := BPF(BPF_PROG_DETACH, unsafe.Pointer(attr), unsafe.Sizeof(*attr))
|
||||
return err
|
||||
}
|
||||
|
||||
type BPFEnableStatsAttr struct {
|
||||
StatsType uint32
|
||||
}
|
||||
|
||||
func BPFEnableStats(attr *BPFEnableStatsAttr) (*FD, error) {
|
||||
ptr, err := BPF(BPF_ENABLE_STATS, unsafe.Pointer(attr), unsafe.Sizeof(*attr))
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("enable stats: %w", err)
|
||||
}
|
||||
return NewFD(uint32(ptr)), nil
|
||||
|
||||
}
|
||||
|
||||
type bpfObjAttr struct {
|
||||
fileName Pointer
|
||||
fd uint32
|
||||
fileFlags uint32
|
||||
}
|
||||
|
||||
const bpfFSType = 0xcafe4a11
|
||||
|
||||
// BPFObjPin wraps BPF_OBJ_PIN.
|
||||
func BPFObjPin(fileName string, fd *FD) error {
|
||||
dirName := filepath.Dir(fileName)
|
||||
var statfs unix.Statfs_t
|
||||
if err := unix.Statfs(dirName, &statfs); err != nil {
|
||||
return err
|
||||
}
|
||||
if uint64(statfs.Type) != bpfFSType {
|
||||
return fmt.Errorf("%s is not on a bpf filesystem", fileName)
|
||||
}
|
||||
|
||||
value, err := fd.Value()
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
attr := bpfObjAttr{
|
||||
fileName: NewStringPointer(fileName),
|
||||
fd: value,
|
||||
}
|
||||
_, err = BPF(BPF_OBJ_PIN, unsafe.Pointer(&attr), unsafe.Sizeof(attr))
|
||||
if err != nil {
|
||||
return fmt.Errorf("pin object %s: %w", fileName, err)
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// BPFObjGet wraps BPF_OBJ_GET.
|
||||
func BPFObjGet(fileName string) (*FD, error) {
|
||||
attr := bpfObjAttr{
|
||||
fileName: NewStringPointer(fileName),
|
||||
}
|
||||
ptr, err := BPF(BPF_OBJ_GET, unsafe.Pointer(&attr), unsafe.Sizeof(attr))
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("get object %s: %w", fileName, err)
|
||||
}
|
||||
return NewFD(uint32(ptr)), nil
|
||||
}
|
||||
|
||||
type bpfObjGetInfoByFDAttr struct {
|
||||
fd uint32
|
||||
infoLen uint32
|
||||
info Pointer
|
||||
}
|
||||
|
||||
// BPFObjGetInfoByFD wraps BPF_OBJ_GET_INFO_BY_FD.
|
||||
//
|
||||
// Available from 4.13.
|
||||
func BPFObjGetInfoByFD(fd *FD, info unsafe.Pointer, size uintptr) error {
|
||||
value, err := fd.Value()
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
attr := bpfObjGetInfoByFDAttr{
|
||||
fd: value,
|
||||
infoLen: uint32(size),
|
||||
info: NewPointer(info),
|
||||
}
|
||||
_, err = BPF(BPF_OBJ_GET_INFO_BY_FD, unsafe.Pointer(&attr), unsafe.Sizeof(attr))
|
||||
if err != nil {
|
||||
return fmt.Errorf("fd %v: %w", fd, err)
|
||||
}
|
||||
return nil
|
||||
}
|
|
@ -1,56 +0,0 @@
|
|||
// Code generated by "stringer -output syscall_string.go -type=BPFCmd"; DO NOT EDIT.
|
||||
|
||||
package internal
|
||||
|
||||
import "strconv"
|
||||
|
||||
func _() {
|
||||
// An "invalid array index" compiler error signifies that the constant values have changed.
|
||||
// Re-run the stringer command to generate them again.
|
||||
var x [1]struct{}
|
||||
_ = x[BPF_MAP_CREATE-0]
|
||||
_ = x[BPF_MAP_LOOKUP_ELEM-1]
|
||||
_ = x[BPF_MAP_UPDATE_ELEM-2]
|
||||
_ = x[BPF_MAP_DELETE_ELEM-3]
|
||||
_ = x[BPF_MAP_GET_NEXT_KEY-4]
|
||||
_ = x[BPF_PROG_LOAD-5]
|
||||
_ = x[BPF_OBJ_PIN-6]
|
||||
_ = x[BPF_OBJ_GET-7]
|
||||
_ = x[BPF_PROG_ATTACH-8]
|
||||
_ = x[BPF_PROG_DETACH-9]
|
||||
_ = x[BPF_PROG_TEST_RUN-10]
|
||||
_ = x[BPF_PROG_GET_NEXT_ID-11]
|
||||
_ = x[BPF_MAP_GET_NEXT_ID-12]
|
||||
_ = x[BPF_PROG_GET_FD_BY_ID-13]
|
||||
_ = x[BPF_MAP_GET_FD_BY_ID-14]
|
||||
_ = x[BPF_OBJ_GET_INFO_BY_FD-15]
|
||||
_ = x[BPF_PROG_QUERY-16]
|
||||
_ = x[BPF_RAW_TRACEPOINT_OPEN-17]
|
||||
_ = x[BPF_BTF_LOAD-18]
|
||||
_ = x[BPF_BTF_GET_FD_BY_ID-19]
|
||||
_ = x[BPF_TASK_FD_QUERY-20]
|
||||
_ = x[BPF_MAP_LOOKUP_AND_DELETE_ELEM-21]
|
||||
_ = x[BPF_MAP_FREEZE-22]
|
||||
_ = x[BPF_BTF_GET_NEXT_ID-23]
|
||||
_ = x[BPF_MAP_LOOKUP_BATCH-24]
|
||||
_ = x[BPF_MAP_LOOKUP_AND_DELETE_BATCH-25]
|
||||
_ = x[BPF_MAP_UPDATE_BATCH-26]
|
||||
_ = x[BPF_MAP_DELETE_BATCH-27]
|
||||
_ = x[BPF_LINK_CREATE-28]
|
||||
_ = x[BPF_LINK_UPDATE-29]
|
||||
_ = x[BPF_LINK_GET_FD_BY_ID-30]
|
||||
_ = x[BPF_LINK_GET_NEXT_ID-31]
|
||||
_ = x[BPF_ENABLE_STATS-32]
|
||||
_ = x[BPF_ITER_CREATE-33]
|
||||
}
|
||||
|
||||
const _BPFCmd_name = "BPF_MAP_CREATEBPF_MAP_LOOKUP_ELEMBPF_MAP_UPDATE_ELEMBPF_MAP_DELETE_ELEMBPF_MAP_GET_NEXT_KEYBPF_PROG_LOADBPF_OBJ_PINBPF_OBJ_GETBPF_PROG_ATTACHBPF_PROG_DETACHBPF_PROG_TEST_RUNBPF_PROG_GET_NEXT_IDBPF_MAP_GET_NEXT_IDBPF_PROG_GET_FD_BY_IDBPF_MAP_GET_FD_BY_IDBPF_OBJ_GET_INFO_BY_FDBPF_PROG_QUERYBPF_RAW_TRACEPOINT_OPENBPF_BTF_LOADBPF_BTF_GET_FD_BY_IDBPF_TASK_FD_QUERYBPF_MAP_LOOKUP_AND_DELETE_ELEMBPF_MAP_FREEZEBPF_BTF_GET_NEXT_IDBPF_MAP_LOOKUP_BATCHBPF_MAP_LOOKUP_AND_DELETE_BATCHBPF_MAP_UPDATE_BATCHBPF_MAP_DELETE_BATCHBPF_LINK_CREATEBPF_LINK_UPDATEBPF_LINK_GET_FD_BY_IDBPF_LINK_GET_NEXT_IDBPF_ENABLE_STATSBPF_ITER_CREATE"
|
||||
|
||||
var _BPFCmd_index = [...]uint16{0, 14, 33, 52, 71, 91, 104, 115, 126, 141, 156, 173, 193, 212, 233, 253, 275, 289, 312, 324, 344, 361, 391, 405, 424, 444, 475, 495, 515, 530, 545, 566, 586, 602, 617}
|
||||
|
||||
func (i BPFCmd) String() string {
|
||||
if i < 0 || i >= BPFCmd(len(_BPFCmd_index)-1) {
|
||||
return "BPFCmd(" + strconv.FormatInt(int64(i), 10) + ")"
|
||||
}
|
||||
return _BPFCmd_name[_BPFCmd_index[i]:_BPFCmd_index[i+1]]
|
||||
}
|
|
@ -1,9 +1,9 @@
|
|||
//go:build linux
|
||||
// +build linux
|
||||
|
||||
package unix
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"syscall"
|
||||
|
||||
linux "golang.org/x/sys/unix"
|
||||
|
@ -20,16 +20,27 @@ const (
|
|||
EPERM = linux.EPERM
|
||||
ESRCH = linux.ESRCH
|
||||
ENODEV = linux.ENODEV
|
||||
EBADF = linux.EBADF
|
||||
E2BIG = linux.E2BIG
|
||||
EFAULT = linux.EFAULT
|
||||
EACCES = linux.EACCES
|
||||
// ENOTSUPP is not the same as ENOTSUP or EOPNOTSUP
|
||||
ENOTSUPP = syscall.Errno(0x20c)
|
||||
|
||||
EBADF = linux.EBADF
|
||||
BPF_F_NO_PREALLOC = linux.BPF_F_NO_PREALLOC
|
||||
BPF_F_NUMA_NODE = linux.BPF_F_NUMA_NODE
|
||||
BPF_F_RDONLY = linux.BPF_F_RDONLY
|
||||
BPF_F_WRONLY = linux.BPF_F_WRONLY
|
||||
BPF_F_RDONLY_PROG = linux.BPF_F_RDONLY_PROG
|
||||
BPF_F_WRONLY_PROG = linux.BPF_F_WRONLY_PROG
|
||||
BPF_F_SLEEPABLE = linux.BPF_F_SLEEPABLE
|
||||
BPF_F_MMAPABLE = linux.BPF_F_MMAPABLE
|
||||
BPF_F_INNER_MAP = linux.BPF_F_INNER_MAP
|
||||
BPF_OBJ_NAME_LEN = linux.BPF_OBJ_NAME_LEN
|
||||
BPF_TAG_SIZE = linux.BPF_TAG_SIZE
|
||||
BPF_RINGBUF_BUSY_BIT = linux.BPF_RINGBUF_BUSY_BIT
|
||||
BPF_RINGBUF_DISCARD_BIT = linux.BPF_RINGBUF_DISCARD_BIT
|
||||
BPF_RINGBUF_HDR_SZ = linux.BPF_RINGBUF_HDR_SZ
|
||||
SYS_BPF = linux.SYS_BPF
|
||||
F_DUPFD_CLOEXEC = linux.F_DUPFD_CLOEXEC
|
||||
EPOLL_CTL_ADD = linux.EPOLL_CTL_ADD
|
||||
|
@ -39,27 +50,36 @@ const (
|
|||
PROT_READ = linux.PROT_READ
|
||||
PROT_WRITE = linux.PROT_WRITE
|
||||
MAP_SHARED = linux.MAP_SHARED
|
||||
PERF_ATTR_SIZE_VER1 = linux.PERF_ATTR_SIZE_VER1
|
||||
PERF_TYPE_SOFTWARE = linux.PERF_TYPE_SOFTWARE
|
||||
PERF_TYPE_TRACEPOINT = linux.PERF_TYPE_TRACEPOINT
|
||||
PERF_COUNT_SW_BPF_OUTPUT = linux.PERF_COUNT_SW_BPF_OUTPUT
|
||||
PERF_EVENT_IOC_DISABLE = linux.PERF_EVENT_IOC_DISABLE
|
||||
PERF_EVENT_IOC_ENABLE = linux.PERF_EVENT_IOC_ENABLE
|
||||
PERF_EVENT_IOC_SET_BPF = linux.PERF_EVENT_IOC_SET_BPF
|
||||
PerfBitWatermark = linux.PerfBitWatermark
|
||||
PERF_SAMPLE_RAW = linux.PERF_SAMPLE_RAW
|
||||
PERF_FLAG_FD_CLOEXEC = linux.PERF_FLAG_FD_CLOEXEC
|
||||
RLIM_INFINITY = linux.RLIM_INFINITY
|
||||
RLIMIT_MEMLOCK = linux.RLIMIT_MEMLOCK
|
||||
BPF_STATS_RUN_TIME = linux.BPF_STATS_RUN_TIME
|
||||
PERF_RECORD_LOST = linux.PERF_RECORD_LOST
|
||||
PERF_RECORD_SAMPLE = linux.PERF_RECORD_SAMPLE
|
||||
AT_FDCWD = linux.AT_FDCWD
|
||||
RENAME_NOREPLACE = linux.RENAME_NOREPLACE
|
||||
SO_ATTACH_BPF = linux.SO_ATTACH_BPF
|
||||
SO_DETACH_BPF = linux.SO_DETACH_BPF
|
||||
SOL_SOCKET = linux.SOL_SOCKET
|
||||
)
|
||||
|
||||
// Statfs_t is a wrapper
|
||||
type Statfs_t = linux.Statfs_t
|
||||
|
||||
type Stat_t = linux.Stat_t
|
||||
|
||||
// Rlimit is a wrapper
|
||||
type Rlimit = linux.Rlimit
|
||||
|
||||
// Setrlimit is a wrapper
|
||||
func Setrlimit(resource int, rlim *Rlimit) (err error) {
|
||||
return linux.Setrlimit(resource, rlim)
|
||||
}
|
||||
|
||||
// Syscall is a wrapper
|
||||
func Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err syscall.Errno) {
|
||||
return linux.Syscall(trap, a1, a2, a3)
|
||||
|
@ -70,6 +90,11 @@ func FcntlInt(fd uintptr, cmd, arg int) (int, error) {
|
|||
return linux.FcntlInt(fd, cmd, arg)
|
||||
}
|
||||
|
||||
// IoctlSetInt is a wrapper
|
||||
func IoctlSetInt(fd int, req uint, value int) error {
|
||||
return linux.IoctlSetInt(fd, req, value)
|
||||
}
|
||||
|
||||
// Statfs is a wrapper
|
||||
func Statfs(path string, buf *Statfs_t) (err error) {
|
||||
return linux.Statfs(path, buf)
|
||||
|
@ -157,14 +182,29 @@ func Tgkill(tgid int, tid int, sig syscall.Signal) (err error) {
|
|||
return linux.Tgkill(tgid, tid, sig)
|
||||
}
|
||||
|
||||
func KernelRelease() (string, error) {
|
||||
var uname Utsname
|
||||
err := Uname(&uname)
|
||||
if err != nil {
|
||||
return "", err
|
||||
// BytePtrFromString is a wrapper
|
||||
func BytePtrFromString(s string) (*byte, error) {
|
||||
return linux.BytePtrFromString(s)
|
||||
}
|
||||
|
||||
end := bytes.IndexByte(uname.Release[:], 0)
|
||||
release := string(uname.Release[:end])
|
||||
return release, nil
|
||||
// ByteSliceToString is a wrapper
|
||||
func ByteSliceToString(s []byte) string {
|
||||
return linux.ByteSliceToString(s)
|
||||
}
|
||||
|
||||
// Renameat2 is a wrapper
|
||||
func Renameat2(olddirfd int, oldpath string, newdirfd int, newpath string, flags uint) error {
|
||||
return linux.Renameat2(olddirfd, oldpath, newdirfd, newpath, flags)
|
||||
}
|
||||
|
||||
func Prlimit(pid, resource int, new, old *Rlimit) error {
|
||||
return linux.Prlimit(pid, resource, new, old)
|
||||
}
|
||||
|
||||
func Open(path string, mode int, perm uint32) (int, error) {
|
||||
return linux.Open(path, mode, perm)
|
||||
}
|
||||
|
||||
func Fstat(fd int, stat *Stat_t) error {
|
||||
return linux.Fstat(fd, stat)
|
||||
}
|
||||
|
|
|
@ -1,3 +1,4 @@
|
|||
//go:build !linux
|
||||
// +build !linux
|
||||
|
||||
package unix
|
||||
|
@ -21,15 +22,26 @@ const (
|
|||
ESRCH = syscall.ESRCH
|
||||
ENODEV = syscall.ENODEV
|
||||
EBADF = syscall.Errno(0)
|
||||
E2BIG = syscall.Errno(0)
|
||||
EFAULT = syscall.EFAULT
|
||||
EACCES = syscall.Errno(0)
|
||||
// ENOTSUPP is not the same as ENOTSUP or EOPNOTSUP
|
||||
ENOTSUPP = syscall.Errno(0x20c)
|
||||
|
||||
BPF_F_NO_PREALLOC = 0
|
||||
BPF_F_NUMA_NODE = 0
|
||||
BPF_F_RDONLY = 0
|
||||
BPF_F_WRONLY = 0
|
||||
BPF_F_RDONLY_PROG = 0
|
||||
BPF_F_WRONLY_PROG = 0
|
||||
BPF_F_SLEEPABLE = 0
|
||||
BPF_F_MMAPABLE = 0
|
||||
BPF_F_INNER_MAP = 0
|
||||
BPF_OBJ_NAME_LEN = 0x10
|
||||
BPF_TAG_SIZE = 0x8
|
||||
BPF_RINGBUF_BUSY_BIT = 0
|
||||
BPF_RINGBUF_DISCARD_BIT = 0
|
||||
BPF_RINGBUF_HDR_SZ = 0
|
||||
SYS_BPF = 321
|
||||
F_DUPFD_CLOEXEC = 0x406
|
||||
EPOLLIN = 0x1
|
||||
|
@ -40,14 +52,26 @@ const (
|
|||
PROT_READ = 0x1
|
||||
PROT_WRITE = 0x2
|
||||
MAP_SHARED = 0x1
|
||||
PERF_ATTR_SIZE_VER1 = 0
|
||||
PERF_TYPE_SOFTWARE = 0x1
|
||||
PERF_TYPE_TRACEPOINT = 0
|
||||
PERF_COUNT_SW_BPF_OUTPUT = 0xa
|
||||
PERF_EVENT_IOC_DISABLE = 0
|
||||
PERF_EVENT_IOC_ENABLE = 0
|
||||
PERF_EVENT_IOC_SET_BPF = 0
|
||||
PerfBitWatermark = 0x4000
|
||||
PERF_SAMPLE_RAW = 0x400
|
||||
PERF_FLAG_FD_CLOEXEC = 0x8
|
||||
RLIM_INFINITY = 0x7fffffffffffffff
|
||||
RLIMIT_MEMLOCK = 8
|
||||
BPF_STATS_RUN_TIME = 0
|
||||
PERF_RECORD_LOST = 2
|
||||
PERF_RECORD_SAMPLE = 9
|
||||
AT_FDCWD = -0x2
|
||||
RENAME_NOREPLACE = 0x1
|
||||
SO_ATTACH_BPF = 0x32
|
||||
SO_DETACH_BPF = 0x1b
|
||||
SOL_SOCKET = 0x1
|
||||
)
|
||||
|
||||
// Statfs_t is a wrapper
|
||||
|
@ -66,17 +90,14 @@ type Statfs_t struct {
|
|||
Spare [4]int64
|
||||
}
|
||||
|
||||
type Stat_t struct{}
|
||||
|
||||
// Rlimit is a wrapper
|
||||
type Rlimit struct {
|
||||
Cur uint64
|
||||
Max uint64
|
||||
}
|
||||
|
||||
// Setrlimit is a wrapper
|
||||
func Setrlimit(resource int, rlim *Rlimit) (err error) {
|
||||
return errNonLinux
|
||||
}
|
||||
|
||||
// Syscall is a wrapper
|
||||
func Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err syscall.Errno) {
|
||||
return 0, 0, syscall.Errno(1)
|
||||
|
@ -87,6 +108,11 @@ func FcntlInt(fd uintptr, cmd, arg int) (int, error) {
|
|||
return -1, errNonLinux
|
||||
}
|
||||
|
||||
// IoctlSetInt is a wrapper
|
||||
func IoctlSetInt(fd int, req uint, value int) error {
|
||||
return errNonLinux
|
||||
}
|
||||
|
||||
// Statfs is a wrapper
|
||||
func Statfs(path string, buf *Statfs_t) error {
|
||||
return errNonLinux
|
||||
|
@ -201,6 +227,7 @@ func PerfEventOpen(attr *PerfEventAttr, pid int, cpu int, groupFd int, flags int
|
|||
// Utsname is a wrapper
|
||||
type Utsname struct {
|
||||
Release [65]byte
|
||||
Version [65]byte
|
||||
}
|
||||
|
||||
// Uname is a wrapper
|
||||
|
@ -223,6 +250,29 @@ func Tgkill(tgid int, tid int, sig syscall.Signal) (err error) {
|
|||
return errNonLinux
|
||||
}
|
||||
|
||||
func KernelRelease() (string, error) {
|
||||
return "", errNonLinux
|
||||
// BytePtrFromString is a wrapper
|
||||
func BytePtrFromString(s string) (*byte, error) {
|
||||
return nil, errNonLinux
|
||||
}
|
||||
|
||||
// ByteSliceToString is a wrapper
|
||||
func ByteSliceToString(s []byte) string {
|
||||
return ""
|
||||
}
|
||||
|
||||
// Renameat2 is a wrapper
|
||||
func Renameat2(olddirfd int, oldpath string, newdirfd int, newpath string, flags uint) error {
|
||||
return errNonLinux
|
||||
}
|
||||
|
||||
func Prlimit(pid, resource int, new, old *Rlimit) error {
|
||||
return errNonLinux
|
||||
}
|
||||
|
||||
func Open(path string, mode int, perm uint32) (int, error) {
|
||||
return -1, errNonLinux
|
||||
}
|
||||
|
||||
func Fstat(fd int, stat *Stat_t) error {
|
||||
return errNonLinux
|
||||
}
|
||||
|
|
|
@ -0,0 +1,150 @@
|
|||
package internal
|
||||
|
||||
import (
|
||||
"debug/elf"
|
||||
"encoding/binary"
|
||||
"errors"
|
||||
"fmt"
|
||||
"io"
|
||||
"math"
|
||||
"os"
|
||||
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
var (
|
||||
errAuxvNoVDSO = errors.New("no vdso address found in auxv")
|
||||
)
|
||||
|
||||
// vdsoVersion returns the LINUX_VERSION_CODE embedded in the vDSO library
|
||||
// linked into the current process image.
|
||||
func vdsoVersion() (uint32, error) {
|
||||
// Read data from the auxiliary vector, which is normally passed directly
|
||||
// to the process. Go does not expose that data, so we must read it from procfs.
|
||||
// https://man7.org/linux/man-pages/man3/getauxval.3.html
|
||||
av, err := os.Open("/proc/self/auxv")
|
||||
if err != nil {
|
||||
return 0, fmt.Errorf("opening auxv: %w", err)
|
||||
}
|
||||
defer av.Close()
|
||||
|
||||
vdsoAddr, err := vdsoMemoryAddress(av)
|
||||
if err != nil {
|
||||
return 0, fmt.Errorf("finding vDSO memory address: %w", err)
|
||||
}
|
||||
|
||||
// Use /proc/self/mem rather than unsafe.Pointer tricks.
|
||||
mem, err := os.Open("/proc/self/mem")
|
||||
if err != nil {
|
||||
return 0, fmt.Errorf("opening mem: %w", err)
|
||||
}
|
||||
defer mem.Close()
|
||||
|
||||
// Open ELF at provided memory address, as offset into /proc/self/mem.
|
||||
c, err := vdsoLinuxVersionCode(io.NewSectionReader(mem, int64(vdsoAddr), math.MaxInt64))
|
||||
if err != nil {
|
||||
return 0, fmt.Errorf("reading linux version code: %w", err)
|
||||
}
|
||||
|
||||
return c, nil
|
||||
}
|
||||
|
||||
// vdsoMemoryAddress returns the memory address of the vDSO library
|
||||
// linked into the current process image. r is an io.Reader into an auxv blob.
|
||||
func vdsoMemoryAddress(r io.Reader) (uint64, error) {
|
||||
const (
|
||||
_AT_NULL = 0 // End of vector
|
||||
_AT_SYSINFO_EHDR = 33 // Offset to vDSO blob in process image
|
||||
)
|
||||
|
||||
// Loop through all tag/value pairs in auxv until we find `AT_SYSINFO_EHDR`,
|
||||
// the address of a page containing the virtual Dynamic Shared Object (vDSO).
|
||||
aux := struct{ Tag, Val uint64 }{}
|
||||
for {
|
||||
if err := binary.Read(r, NativeEndian, &aux); err != nil {
|
||||
return 0, fmt.Errorf("reading auxv entry: %w", err)
|
||||
}
|
||||
|
||||
switch aux.Tag {
|
||||
case _AT_SYSINFO_EHDR:
|
||||
if aux.Val != 0 {
|
||||
return aux.Val, nil
|
||||
}
|
||||
return 0, fmt.Errorf("invalid vDSO address in auxv")
|
||||
// _AT_NULL is always the last tag/val pair in the aux vector
|
||||
// and can be treated like EOF.
|
||||
case _AT_NULL:
|
||||
return 0, errAuxvNoVDSO
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// format described at https://www.man7.org/linux/man-pages/man5/elf.5.html in section 'Notes (Nhdr)'
|
||||
type elfNoteHeader struct {
|
||||
NameSize int32
|
||||
DescSize int32
|
||||
Type int32
|
||||
}
|
||||
|
||||
// vdsoLinuxVersionCode returns the LINUX_VERSION_CODE embedded in
|
||||
// the ELF notes section of the binary provided by the reader.
|
||||
func vdsoLinuxVersionCode(r io.ReaderAt) (uint32, error) {
|
||||
hdr, err := NewSafeELFFile(r)
|
||||
if err != nil {
|
||||
return 0, fmt.Errorf("reading vDSO ELF: %w", err)
|
||||
}
|
||||
|
||||
sections := hdr.SectionsByType(elf.SHT_NOTE)
|
||||
if len(sections) == 0 {
|
||||
return 0, fmt.Errorf("no note section found in vDSO ELF")
|
||||
}
|
||||
|
||||
for _, sec := range sections {
|
||||
sr := sec.Open()
|
||||
var n elfNoteHeader
|
||||
|
||||
// Read notes until we find one named 'Linux'.
|
||||
for {
|
||||
if err := binary.Read(sr, hdr.ByteOrder, &n); err != nil {
|
||||
if errors.Is(err, io.EOF) {
|
||||
// We looked at all the notes in this section
|
||||
break
|
||||
}
|
||||
return 0, fmt.Errorf("reading note header: %w", err)
|
||||
}
|
||||
|
||||
// If a note name is defined, it follows the note header.
|
||||
var name string
|
||||
if n.NameSize > 0 {
|
||||
// Read the note name, aligned to 4 bytes.
|
||||
buf := make([]byte, Align(int(n.NameSize), 4))
|
||||
if err := binary.Read(sr, hdr.ByteOrder, &buf); err != nil {
|
||||
return 0, fmt.Errorf("reading note name: %w", err)
|
||||
}
|
||||
|
||||
// Read nul-terminated string.
|
||||
name = unix.ByteSliceToString(buf[:n.NameSize])
|
||||
}
|
||||
|
||||
// If a note descriptor is defined, it follows the name.
|
||||
// It is possible for a note to have a descriptor but not a name.
|
||||
if n.DescSize > 0 {
|
||||
// LINUX_VERSION_CODE is a uint32 value.
|
||||
if name == "Linux" && n.DescSize == 4 && n.Type == 0 {
|
||||
var version uint32
|
||||
if err := binary.Read(sr, hdr.ByteOrder, &version); err != nil {
|
||||
return 0, fmt.Errorf("reading note descriptor: %w", err)
|
||||
}
|
||||
return version, nil
|
||||
}
|
||||
|
||||
// Discard the note descriptor if it exists but we're not interested in it.
|
||||
if _, err := io.CopyN(io.Discard, sr, int64(Align(int(n.DescSize), 4))); err != nil {
|
||||
return 0, err
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return 0, fmt.Errorf("no Linux note in ELF")
|
||||
}
|
|
@ -0,0 +1,122 @@
|
|||
package internal
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
"sync"
|
||||
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
const (
|
||||
// Version constant used in ELF binaries indicating that the loader needs to
|
||||
// substitute the eBPF program's version with the value of the kernel's
|
||||
// KERNEL_VERSION compile-time macro. Used for compatibility with BCC, gobpf
|
||||
// and RedSift.
|
||||
MagicKernelVersion = 0xFFFFFFFE
|
||||
)
|
||||
|
||||
var (
|
||||
kernelVersion = struct {
|
||||
once sync.Once
|
||||
version Version
|
||||
err error
|
||||
}{}
|
||||
)
|
||||
|
||||
// A Version in the form Major.Minor.Patch.
|
||||
type Version [3]uint16
|
||||
|
||||
// NewVersion creates a version from a string like "Major.Minor.Patch".
|
||||
//
|
||||
// Patch is optional.
|
||||
func NewVersion(ver string) (Version, error) {
|
||||
var major, minor, patch uint16
|
||||
n, _ := fmt.Sscanf(ver, "%d.%d.%d", &major, &minor, &patch)
|
||||
if n < 2 {
|
||||
return Version{}, fmt.Errorf("invalid version: %s", ver)
|
||||
}
|
||||
return Version{major, minor, patch}, nil
|
||||
}
|
||||
|
||||
// NewVersionFromCode creates a version from a LINUX_VERSION_CODE.
|
||||
func NewVersionFromCode(code uint32) Version {
|
||||
return Version{
|
||||
uint16(uint8(code >> 16)),
|
||||
uint16(uint8(code >> 8)),
|
||||
uint16(uint8(code)),
|
||||
}
|
||||
}
|
||||
|
||||
func (v Version) String() string {
|
||||
if v[2] == 0 {
|
||||
return fmt.Sprintf("v%d.%d", v[0], v[1])
|
||||
}
|
||||
return fmt.Sprintf("v%d.%d.%d", v[0], v[1], v[2])
|
||||
}
|
||||
|
||||
// Less returns true if the version is less than another version.
|
||||
func (v Version) Less(other Version) bool {
|
||||
for i, a := range v {
|
||||
if a == other[i] {
|
||||
continue
|
||||
}
|
||||
return a < other[i]
|
||||
}
|
||||
return false
|
||||
}
|
||||
|
||||
// Unspecified returns true if the version is all zero.
|
||||
func (v Version) Unspecified() bool {
|
||||
return v[0] == 0 && v[1] == 0 && v[2] == 0
|
||||
}
|
||||
|
||||
// Kernel implements the kernel's KERNEL_VERSION macro from linux/version.h.
|
||||
// It represents the kernel version and patch level as a single value.
|
||||
func (v Version) Kernel() uint32 {
|
||||
|
||||
// Kernels 4.4 and 4.9 have their SUBLEVEL clamped to 255 to avoid
|
||||
// overflowing into PATCHLEVEL.
|
||||
// See kernel commit 9b82f13e7ef3 ("kbuild: clamp SUBLEVEL to 255").
|
||||
s := v[2]
|
||||
if s > 255 {
|
||||
s = 255
|
||||
}
|
||||
|
||||
// Truncate members to uint8 to prevent them from spilling over into
|
||||
// each other when overflowing 8 bits.
|
||||
return uint32(uint8(v[0]))<<16 | uint32(uint8(v[1]))<<8 | uint32(uint8(s))
|
||||
}
|
||||
|
||||
// KernelVersion returns the version of the currently running kernel.
|
||||
func KernelVersion() (Version, error) {
|
||||
kernelVersion.once.Do(func() {
|
||||
kernelVersion.version, kernelVersion.err = detectKernelVersion()
|
||||
})
|
||||
|
||||
if kernelVersion.err != nil {
|
||||
return Version{}, kernelVersion.err
|
||||
}
|
||||
return kernelVersion.version, nil
|
||||
}
|
||||
|
||||
// detectKernelVersion returns the version of the running kernel.
|
||||
func detectKernelVersion() (Version, error) {
|
||||
vc, err := vdsoVersion()
|
||||
if err != nil {
|
||||
return Version{}, err
|
||||
}
|
||||
return NewVersionFromCode(vc), nil
|
||||
}
|
||||
|
||||
// KernelRelease returns the release string of the running kernel.
|
||||
// Its format depends on the Linux distribution and corresponds to directory
|
||||
// names in /lib/modules by convention. Some examples are 5.15.17-1-lts and
|
||||
// 4.19.0-16-amd64.
|
||||
func KernelRelease() (string, error) {
|
||||
var uname unix.Utsname
|
||||
if err := unix.Uname(&uname); err != nil {
|
||||
return "", fmt.Errorf("uname failed: %w", err)
|
||||
}
|
||||
|
||||
return unix.ByteSliceToString(uname.Release[:]), nil
|
||||
}
|
|
@ -56,16 +56,6 @@ func AttachCgroup(opts CgroupOptions) (Link, error) {
|
|||
return cg, nil
|
||||
}
|
||||
|
||||
// LoadPinnedCgroup loads a pinned cgroup from a bpffs.
|
||||
func LoadPinnedCgroup(fileName string) (Link, error) {
|
||||
link, err := LoadPinnedRawLink(fileName)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return &linkCgroup{link}, nil
|
||||
}
|
||||
|
||||
type progAttachCgroup struct {
|
||||
cgroup *os.File
|
||||
current *ebpf.Program
|
||||
|
@ -147,14 +137,20 @@ func (cg *progAttachCgroup) Pin(string) error {
|
|||
return fmt.Errorf("can't pin cgroup: %w", ErrNotSupported)
|
||||
}
|
||||
|
||||
func (cg *progAttachCgroup) Unpin() error {
|
||||
return fmt.Errorf("can't pin cgroup: %w", ErrNotSupported)
|
||||
}
|
||||
|
||||
func (cg *progAttachCgroup) Info() (*Info, error) {
|
||||
return nil, fmt.Errorf("can't get cgroup info: %w", ErrNotSupported)
|
||||
}
|
||||
|
||||
type linkCgroup struct {
|
||||
*RawLink
|
||||
RawLink
|
||||
}
|
||||
|
||||
var _ Link = (*linkCgroup)(nil)
|
||||
|
||||
func (cg *linkCgroup) isLink() {}
|
||||
|
||||
func newLinkCgroup(cgroup *os.File, attach ebpf.AttachType, prog *ebpf.Program) (*linkCgroup, error) {
|
||||
link, err := AttachRawLink(RawLinkOptions{
|
||||
Target: int(cgroup.Fd()),
|
||||
|
@ -165,5 +161,5 @@ func newLinkCgroup(cgroup *os.File, attach ebpf.AttachType, prog *ebpf.Program)
|
|||
return nil, err
|
||||
}
|
||||
|
||||
return &linkCgroup{link}, err
|
||||
return &linkCgroup{*link}, err
|
||||
}
|
||||
|
|
|
@ -3,8 +3,10 @@ package link
|
|||
import (
|
||||
"fmt"
|
||||
"io"
|
||||
"unsafe"
|
||||
|
||||
"github.com/cilium/ebpf"
|
||||
"github.com/cilium/ebpf/internal/sys"
|
||||
)
|
||||
|
||||
type IterOptions struct {
|
||||
|
@ -15,77 +17,69 @@ type IterOptions struct {
|
|||
// AttachTo requires the kernel to include BTF of itself,
|
||||
// and it to be compiled with a recent pahole (>= 1.16).
|
||||
Program *ebpf.Program
|
||||
|
||||
// Map specifies the target map for bpf_map_elem and sockmap iterators.
|
||||
// It may be nil.
|
||||
Map *ebpf.Map
|
||||
}
|
||||
|
||||
// AttachIter attaches a BPF seq_file iterator.
|
||||
func AttachIter(opts IterOptions) (*Iter, error) {
|
||||
link, err := AttachRawLink(RawLinkOptions{
|
||||
Program: opts.Program,
|
||||
Attach: ebpf.AttachTraceIter,
|
||||
})
|
||||
if err := haveBPFLink(); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
progFd := opts.Program.FD()
|
||||
if progFd < 0 {
|
||||
return nil, fmt.Errorf("invalid program: %s", sys.ErrClosedFd)
|
||||
}
|
||||
|
||||
var info bpfIterLinkInfoMap
|
||||
if opts.Map != nil {
|
||||
mapFd := opts.Map.FD()
|
||||
if mapFd < 0 {
|
||||
return nil, fmt.Errorf("invalid map: %w", sys.ErrClosedFd)
|
||||
}
|
||||
info.map_fd = uint32(mapFd)
|
||||
}
|
||||
|
||||
attr := sys.LinkCreateIterAttr{
|
||||
ProgFd: uint32(progFd),
|
||||
AttachType: sys.AttachType(ebpf.AttachTraceIter),
|
||||
IterInfo: sys.NewPointer(unsafe.Pointer(&info)),
|
||||
IterInfoLen: uint32(unsafe.Sizeof(info)),
|
||||
}
|
||||
|
||||
fd, err := sys.LinkCreateIter(&attr)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("can't link iterator: %w", err)
|
||||
}
|
||||
|
||||
return &Iter{link}, err
|
||||
}
|
||||
|
||||
// LoadPinnedIter loads a pinned iterator from a bpffs.
|
||||
func LoadPinnedIter(fileName string) (*Iter, error) {
|
||||
link, err := LoadPinnedRawLink(fileName)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return &Iter{link}, err
|
||||
return &Iter{RawLink{fd, ""}}, err
|
||||
}
|
||||
|
||||
// Iter represents an attached bpf_iter.
|
||||
type Iter struct {
|
||||
link *RawLink
|
||||
}
|
||||
|
||||
var _ Link = (*Iter)(nil)
|
||||
|
||||
func (it *Iter) isLink() {}
|
||||
|
||||
// FD returns the underlying file descriptor.
|
||||
func (it *Iter) FD() int {
|
||||
return it.link.FD()
|
||||
}
|
||||
|
||||
// Close implements Link.
|
||||
func (it *Iter) Close() error {
|
||||
return it.link.Close()
|
||||
}
|
||||
|
||||
// Pin implements Link.
|
||||
func (it *Iter) Pin(fileName string) error {
|
||||
return it.link.Pin(fileName)
|
||||
}
|
||||
|
||||
// Update implements Link.
|
||||
func (it *Iter) Update(new *ebpf.Program) error {
|
||||
return it.link.Update(new)
|
||||
RawLink
|
||||
}
|
||||
|
||||
// Open creates a new instance of the iterator.
|
||||
//
|
||||
// Reading from the returned reader triggers the BPF program.
|
||||
func (it *Iter) Open() (io.ReadCloser, error) {
|
||||
linkFd, err := it.link.fd.Value()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
attr := &sys.IterCreateAttr{
|
||||
LinkFd: it.fd.Uint(),
|
||||
}
|
||||
|
||||
attr := &bpfIterCreateAttr{
|
||||
linkFd: linkFd,
|
||||
}
|
||||
|
||||
fd, err := bpfIterCreate(attr)
|
||||
fd, err := sys.IterCreate(attr)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("can't create iterator: %w", err)
|
||||
}
|
||||
|
||||
return fd.File("bpf_iter"), nil
|
||||
}
|
||||
|
||||
// union bpf_iter_link_info.map
|
||||
type bpfIterLinkInfoMap struct {
|
||||
map_fd uint32
|
||||
}
|
||||
|
|
|
@ -0,0 +1,568 @@
|
|||
package link
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"crypto/rand"
|
||||
"errors"
|
||||
"fmt"
|
||||
"os"
|
||||
"path/filepath"
|
||||
"runtime"
|
||||
"strings"
|
||||
"sync"
|
||||
"syscall"
|
||||
"unsafe"
|
||||
|
||||
"github.com/cilium/ebpf"
|
||||
"github.com/cilium/ebpf/internal/sys"
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
var (
|
||||
kprobeEventsPath = filepath.Join(tracefsPath, "kprobe_events")
|
||||
|
||||
kprobeRetprobeBit = struct {
|
||||
once sync.Once
|
||||
value uint64
|
||||
err error
|
||||
}{}
|
||||
)
|
||||
|
||||
type probeType uint8
|
||||
|
||||
type probeArgs struct {
|
||||
symbol, group, path string
|
||||
offset, refCtrOffset, cookie uint64
|
||||
pid int
|
||||
ret bool
|
||||
}
|
||||
|
||||
// KprobeOptions defines additional parameters that will be used
|
||||
// when loading Kprobes.
|
||||
type KprobeOptions struct {
|
||||
// Arbitrary value that can be fetched from an eBPF program
|
||||
// via `bpf_get_attach_cookie()`.
|
||||
//
|
||||
// Needs kernel 5.15+.
|
||||
Cookie uint64
|
||||
// Offset of the kprobe relative to the traced symbol.
|
||||
// Can be used to insert kprobes at arbitrary offsets in kernel functions,
|
||||
// e.g. in places where functions have been inlined.
|
||||
Offset uint64
|
||||
}
|
||||
|
||||
const (
|
||||
kprobeType probeType = iota
|
||||
uprobeType
|
||||
)
|
||||
|
||||
func (pt probeType) String() string {
|
||||
if pt == kprobeType {
|
||||
return "kprobe"
|
||||
}
|
||||
return "uprobe"
|
||||
}
|
||||
|
||||
func (pt probeType) EventsPath() string {
|
||||
if pt == kprobeType {
|
||||
return kprobeEventsPath
|
||||
}
|
||||
return uprobeEventsPath
|
||||
}
|
||||
|
||||
func (pt probeType) PerfEventType(ret bool) perfEventType {
|
||||
if pt == kprobeType {
|
||||
if ret {
|
||||
return kretprobeEvent
|
||||
}
|
||||
return kprobeEvent
|
||||
}
|
||||
if ret {
|
||||
return uretprobeEvent
|
||||
}
|
||||
return uprobeEvent
|
||||
}
|
||||
|
||||
func (pt probeType) RetprobeBit() (uint64, error) {
|
||||
if pt == kprobeType {
|
||||
return kretprobeBit()
|
||||
}
|
||||
return uretprobeBit()
|
||||
}
|
||||
|
||||
// Kprobe attaches the given eBPF program to a perf event that fires when the
|
||||
// given kernel symbol starts executing. See /proc/kallsyms for available
|
||||
// symbols. For example, printk():
|
||||
//
|
||||
// kp, err := Kprobe("printk", prog, nil)
|
||||
//
|
||||
// Losing the reference to the resulting Link (kp) will close the Kprobe
|
||||
// and prevent further execution of prog. The Link must be Closed during
|
||||
// program shutdown to avoid leaking system resources.
|
||||
func Kprobe(symbol string, prog *ebpf.Program, opts *KprobeOptions) (Link, error) {
|
||||
k, err := kprobe(symbol, prog, opts, false)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
lnk, err := attachPerfEvent(k, prog)
|
||||
if err != nil {
|
||||
k.Close()
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return lnk, nil
|
||||
}
|
||||
|
||||
// Kretprobe attaches the given eBPF program to a perf event that fires right
|
||||
// before the given kernel symbol exits, with the function stack left intact.
|
||||
// See /proc/kallsyms for available symbols. For example, printk():
|
||||
//
|
||||
// kp, err := Kretprobe("printk", prog, nil)
|
||||
//
|
||||
// Losing the reference to the resulting Link (kp) will close the Kretprobe
|
||||
// and prevent further execution of prog. The Link must be Closed during
|
||||
// program shutdown to avoid leaking system resources.
|
||||
func Kretprobe(symbol string, prog *ebpf.Program, opts *KprobeOptions) (Link, error) {
|
||||
k, err := kprobe(symbol, prog, opts, true)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
lnk, err := attachPerfEvent(k, prog)
|
||||
if err != nil {
|
||||
k.Close()
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return lnk, nil
|
||||
}
|
||||
|
||||
// isValidKprobeSymbol implements the equivalent of a regex match
|
||||
// against "^[a-zA-Z_][0-9a-zA-Z_.]*$".
|
||||
func isValidKprobeSymbol(s string) bool {
|
||||
if len(s) < 1 {
|
||||
return false
|
||||
}
|
||||
|
||||
for i, c := range []byte(s) {
|
||||
switch {
|
||||
case c >= 'a' && c <= 'z':
|
||||
case c >= 'A' && c <= 'Z':
|
||||
case c == '_':
|
||||
case i > 0 && c >= '0' && c <= '9':
|
||||
|
||||
// Allow `.` in symbol name. GCC-compiled kernel may change symbol name
|
||||
// to have a `.isra.$n` suffix, like `udp_send_skb.isra.52`.
|
||||
// See: https://gcc.gnu.org/gcc-10/changes.html
|
||||
case i > 0 && c == '.':
|
||||
|
||||
default:
|
||||
return false
|
||||
}
|
||||
}
|
||||
|
||||
return true
|
||||
}
|
||||
|
||||
// kprobe opens a perf event on the given symbol and attaches prog to it.
|
||||
// If ret is true, create a kretprobe.
|
||||
func kprobe(symbol string, prog *ebpf.Program, opts *KprobeOptions, ret bool) (*perfEvent, error) {
|
||||
if symbol == "" {
|
||||
return nil, fmt.Errorf("symbol name cannot be empty: %w", errInvalidInput)
|
||||
}
|
||||
if prog == nil {
|
||||
return nil, fmt.Errorf("prog cannot be nil: %w", errInvalidInput)
|
||||
}
|
||||
if !isValidKprobeSymbol(symbol) {
|
||||
return nil, fmt.Errorf("symbol '%s' must be a valid symbol in /proc/kallsyms: %w", symbol, errInvalidInput)
|
||||
}
|
||||
if prog.Type() != ebpf.Kprobe {
|
||||
return nil, fmt.Errorf("eBPF program type %s is not a Kprobe: %w", prog.Type(), errInvalidInput)
|
||||
}
|
||||
|
||||
args := probeArgs{
|
||||
pid: perfAllThreads,
|
||||
symbol: symbol,
|
||||
ret: ret,
|
||||
}
|
||||
|
||||
if opts != nil {
|
||||
args.cookie = opts.Cookie
|
||||
args.offset = opts.Offset
|
||||
}
|
||||
|
||||
// Use kprobe PMU if the kernel has it available.
|
||||
tp, err := pmuKprobe(args)
|
||||
if errors.Is(err, os.ErrNotExist) {
|
||||
args.symbol = platformPrefix(symbol)
|
||||
tp, err = pmuKprobe(args)
|
||||
}
|
||||
if err == nil {
|
||||
return tp, nil
|
||||
}
|
||||
if err != nil && !errors.Is(err, ErrNotSupported) {
|
||||
return nil, fmt.Errorf("creating perf_kprobe PMU: %w", err)
|
||||
}
|
||||
|
||||
// Use tracefs if kprobe PMU is missing.
|
||||
args.symbol = symbol
|
||||
tp, err = tracefsKprobe(args)
|
||||
if errors.Is(err, os.ErrNotExist) {
|
||||
args.symbol = platformPrefix(symbol)
|
||||
tp, err = tracefsKprobe(args)
|
||||
}
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("creating trace event '%s' in tracefs: %w", symbol, err)
|
||||
}
|
||||
|
||||
return tp, nil
|
||||
}
|
||||
|
||||
// pmuKprobe opens a perf event based on the kprobe PMU.
|
||||
// Returns os.ErrNotExist if the given symbol does not exist in the kernel.
|
||||
func pmuKprobe(args probeArgs) (*perfEvent, error) {
|
||||
return pmuProbe(kprobeType, args)
|
||||
}
|
||||
|
||||
// pmuProbe opens a perf event based on a Performance Monitoring Unit.
|
||||
//
|
||||
// Requires at least a 4.17 kernel.
|
||||
// e12f03d7031a "perf/core: Implement the 'perf_kprobe' PMU"
|
||||
// 33ea4b24277b "perf/core: Implement the 'perf_uprobe' PMU"
|
||||
//
|
||||
// Returns ErrNotSupported if the kernel doesn't support perf_[k,u]probe PMU
|
||||
func pmuProbe(typ probeType, args probeArgs) (*perfEvent, error) {
|
||||
// Getting the PMU type will fail if the kernel doesn't support
|
||||
// the perf_[k,u]probe PMU.
|
||||
et, err := getPMUEventType(typ)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
var config uint64
|
||||
if args.ret {
|
||||
bit, err := typ.RetprobeBit()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
config |= 1 << bit
|
||||
}
|
||||
|
||||
var (
|
||||
attr unix.PerfEventAttr
|
||||
sp unsafe.Pointer
|
||||
)
|
||||
switch typ {
|
||||
case kprobeType:
|
||||
// Create a pointer to a NUL-terminated string for the kernel.
|
||||
sp, err = unsafeStringPtr(args.symbol)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
attr = unix.PerfEventAttr{
|
||||
// The minimum size required for PMU kprobes is PERF_ATTR_SIZE_VER1,
|
||||
// since it added the config2 (Ext2) field. Use Ext2 as probe_offset.
|
||||
Size: unix.PERF_ATTR_SIZE_VER1,
|
||||
Type: uint32(et), // PMU event type read from sysfs
|
||||
Ext1: uint64(uintptr(sp)), // Kernel symbol to trace
|
||||
Ext2: args.offset, // Kernel symbol offset
|
||||
Config: config, // Retprobe flag
|
||||
}
|
||||
case uprobeType:
|
||||
sp, err = unsafeStringPtr(args.path)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
if args.refCtrOffset != 0 {
|
||||
config |= args.refCtrOffset << uprobeRefCtrOffsetShift
|
||||
}
|
||||
|
||||
attr = unix.PerfEventAttr{
|
||||
// The minimum size required for PMU uprobes is PERF_ATTR_SIZE_VER1,
|
||||
// since it added the config2 (Ext2) field. The Size field controls the
|
||||
// size of the internal buffer the kernel allocates for reading the
|
||||
// perf_event_attr argument from userspace.
|
||||
Size: unix.PERF_ATTR_SIZE_VER1,
|
||||
Type: uint32(et), // PMU event type read from sysfs
|
||||
Ext1: uint64(uintptr(sp)), // Uprobe path
|
||||
Ext2: args.offset, // Uprobe offset
|
||||
Config: config, // RefCtrOffset, Retprobe flag
|
||||
}
|
||||
}
|
||||
|
||||
rawFd, err := unix.PerfEventOpen(&attr, args.pid, 0, -1, unix.PERF_FLAG_FD_CLOEXEC)
|
||||
|
||||
// On some old kernels, kprobe PMU doesn't allow `.` in symbol names and
|
||||
// return -EINVAL. Return ErrNotSupported to allow falling back to tracefs.
|
||||
// https://github.com/torvalds/linux/blob/94710cac0ef4/kernel/trace/trace_kprobe.c#L340-L343
|
||||
if errors.Is(err, unix.EINVAL) && strings.Contains(args.symbol, ".") {
|
||||
return nil, fmt.Errorf("symbol '%s+%#x': older kernels don't accept dots: %w", args.symbol, args.offset, ErrNotSupported)
|
||||
}
|
||||
// Since commit 97c753e62e6c, ENOENT is correctly returned instead of EINVAL
|
||||
// when trying to create a kretprobe for a missing symbol. Make sure ENOENT
|
||||
// is returned to the caller.
|
||||
if errors.Is(err, os.ErrNotExist) || errors.Is(err, unix.EINVAL) {
|
||||
return nil, fmt.Errorf("symbol '%s+%#x' not found: %w", args.symbol, args.offset, os.ErrNotExist)
|
||||
}
|
||||
// Since commit ab105a4fb894, -EILSEQ is returned when a kprobe sym+offset is resolved
|
||||
// to an invalid insn boundary.
|
||||
if errors.Is(err, syscall.EILSEQ) {
|
||||
return nil, fmt.Errorf("symbol '%s+%#x' not found (bad insn boundary): %w", args.symbol, args.offset, os.ErrNotExist)
|
||||
}
|
||||
// Since at least commit cb9a19fe4aa51, ENOTSUPP is returned
|
||||
// when attempting to set a uprobe on a trap instruction.
|
||||
if errors.Is(err, unix.ENOTSUPP) {
|
||||
return nil, fmt.Errorf("failed setting uprobe on offset %#x (possible trap insn): %w", args.offset, err)
|
||||
}
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("opening perf event: %w", err)
|
||||
}
|
||||
|
||||
// Ensure the string pointer is not collected before PerfEventOpen returns.
|
||||
runtime.KeepAlive(sp)
|
||||
|
||||
fd, err := sys.NewFD(rawFd)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// Kernel has perf_[k,u]probe PMU available, initialize perf event.
|
||||
return &perfEvent{
|
||||
typ: typ.PerfEventType(args.ret),
|
||||
name: args.symbol,
|
||||
pmuID: et,
|
||||
cookie: args.cookie,
|
||||
fd: fd,
|
||||
}, nil
|
||||
}
|
||||
|
||||
// tracefsKprobe creates a Kprobe tracefs entry.
|
||||
func tracefsKprobe(args probeArgs) (*perfEvent, error) {
|
||||
return tracefsProbe(kprobeType, args)
|
||||
}
|
||||
|
||||
// tracefsProbe creates a trace event by writing an entry to <tracefs>/[k,u]probe_events.
|
||||
// A new trace event group name is generated on every call to support creating
|
||||
// multiple trace events for the same kernel or userspace symbol.
|
||||
// Path and offset are only set in the case of uprobe(s) and are used to set
|
||||
// the executable/library path on the filesystem and the offset where the probe is inserted.
|
||||
// A perf event is then opened on the newly-created trace event and returned to the caller.
|
||||
func tracefsProbe(typ probeType, args probeArgs) (_ *perfEvent, err error) {
|
||||
// Generate a random string for each trace event we attempt to create.
|
||||
// This value is used as the 'group' token in tracefs to allow creating
|
||||
// multiple kprobe trace events with the same name.
|
||||
group, err := randomGroup("ebpf")
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("randomizing group name: %w", err)
|
||||
}
|
||||
args.group = group
|
||||
|
||||
// Before attempting to create a trace event through tracefs,
|
||||
// check if an event with the same group and name already exists.
|
||||
// Kernels 4.x and earlier don't return os.ErrExist on writing a duplicate
|
||||
// entry, so we need to rely on reads for detecting uniqueness.
|
||||
_, err = getTraceEventID(group, args.symbol)
|
||||
if err == nil {
|
||||
return nil, fmt.Errorf("trace event already exists: %s/%s", group, args.symbol)
|
||||
}
|
||||
if err != nil && !errors.Is(err, os.ErrNotExist) {
|
||||
return nil, fmt.Errorf("checking trace event %s/%s: %w", group, args.symbol, err)
|
||||
}
|
||||
|
||||
// Create the [k,u]probe trace event using tracefs.
|
||||
if err := createTraceFSProbeEvent(typ, args); err != nil {
|
||||
return nil, fmt.Errorf("creating probe entry on tracefs: %w", err)
|
||||
}
|
||||
defer func() {
|
||||
if err != nil {
|
||||
// Make sure we clean up the created tracefs event when we return error.
|
||||
// If a livepatch handler is already active on the symbol, the write to
|
||||
// tracefs will succeed, a trace event will show up, but creating the
|
||||
// perf event will fail with EBUSY.
|
||||
_ = closeTraceFSProbeEvent(typ, args.group, args.symbol)
|
||||
}
|
||||
}()
|
||||
|
||||
// Get the newly-created trace event's id.
|
||||
tid, err := getTraceEventID(group, args.symbol)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("getting trace event id: %w", err)
|
||||
}
|
||||
|
||||
// Kprobes are ephemeral tracepoints and share the same perf event type.
|
||||
fd, err := openTracepointPerfEvent(tid, args.pid)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return &perfEvent{
|
||||
typ: typ.PerfEventType(args.ret),
|
||||
group: group,
|
||||
name: args.symbol,
|
||||
tracefsID: tid,
|
||||
cookie: args.cookie,
|
||||
fd: fd,
|
||||
}, nil
|
||||
}
|
||||
|
||||
// createTraceFSProbeEvent creates a new ephemeral trace event by writing to
|
||||
// <tracefs>/[k,u]probe_events. Returns os.ErrNotExist if symbol is not a valid
|
||||
// kernel symbol, or if it is not traceable with kprobes. Returns os.ErrExist
|
||||
// if a probe with the same group and symbol already exists.
|
||||
func createTraceFSProbeEvent(typ probeType, args probeArgs) error {
|
||||
// Open the kprobe_events file in tracefs.
|
||||
f, err := os.OpenFile(typ.EventsPath(), os.O_APPEND|os.O_WRONLY, 0666)
|
||||
if err != nil {
|
||||
return fmt.Errorf("error opening '%s': %w", typ.EventsPath(), err)
|
||||
}
|
||||
defer f.Close()
|
||||
|
||||
var pe, token string
|
||||
switch typ {
|
||||
case kprobeType:
|
||||
// The kprobe_events syntax is as follows (see Documentation/trace/kprobetrace.txt):
|
||||
// p[:[GRP/]EVENT] [MOD:]SYM[+offs]|MEMADDR [FETCHARGS] : Set a probe
|
||||
// r[MAXACTIVE][:[GRP/]EVENT] [MOD:]SYM[+0] [FETCHARGS] : Set a return probe
|
||||
// -:[GRP/]EVENT : Clear a probe
|
||||
//
|
||||
// Some examples:
|
||||
// r:ebpf_1234/r_my_kretprobe nf_conntrack_destroy
|
||||
// p:ebpf_5678/p_my_kprobe __x64_sys_execve
|
||||
//
|
||||
// Leaving the kretprobe's MAXACTIVE set to 0 (or absent) will make the
|
||||
// kernel default to NR_CPUS. This is desired in most eBPF cases since
|
||||
// subsampling or rate limiting logic can be more accurately implemented in
|
||||
// the eBPF program itself.
|
||||
// See Documentation/kprobes.txt for more details.
|
||||
token = kprobeToken(args)
|
||||
pe = fmt.Sprintf("%s:%s/%s %s", probePrefix(args.ret), args.group, sanitizeSymbol(args.symbol), token)
|
||||
case uprobeType:
|
||||
// The uprobe_events syntax is as follows:
|
||||
// p[:[GRP/]EVENT] PATH:OFFSET [FETCHARGS] : Set a probe
|
||||
// r[:[GRP/]EVENT] PATH:OFFSET [FETCHARGS] : Set a return probe
|
||||
// -:[GRP/]EVENT : Clear a probe
|
||||
//
|
||||
// Some examples:
|
||||
// r:ebpf_1234/readline /bin/bash:0x12345
|
||||
// p:ebpf_5678/main_mySymbol /bin/mybin:0x12345(0x123)
|
||||
//
|
||||
// See Documentation/trace/uprobetracer.txt for more details.
|
||||
token = uprobeToken(args)
|
||||
pe = fmt.Sprintf("%s:%s/%s %s", probePrefix(args.ret), args.group, args.symbol, token)
|
||||
}
|
||||
_, err = f.WriteString(pe)
|
||||
// Since commit 97c753e62e6c, ENOENT is correctly returned instead of EINVAL
|
||||
// when trying to create a kretprobe for a missing symbol. Make sure ENOENT
|
||||
// is returned to the caller.
|
||||
// EINVAL is also returned on pre-5.2 kernels when the `SYM[+offs]` token
|
||||
// is resolved to an invalid insn boundary.
|
||||
if errors.Is(err, os.ErrNotExist) || errors.Is(err, unix.EINVAL) {
|
||||
return fmt.Errorf("token %s: %w", token, os.ErrNotExist)
|
||||
}
|
||||
// Since commit ab105a4fb894, -EILSEQ is returned when a kprobe sym+offset is resolved
|
||||
// to an invalid insn boundary.
|
||||
if errors.Is(err, syscall.EILSEQ) {
|
||||
return fmt.Errorf("token %s: bad insn boundary: %w", token, os.ErrNotExist)
|
||||
}
|
||||
// ERANGE is returned when the `SYM[+offs]` token is too big and cannot
|
||||
// be resolved.
|
||||
if errors.Is(err, syscall.ERANGE) {
|
||||
return fmt.Errorf("token %s: offset too big: %w", token, os.ErrNotExist)
|
||||
}
|
||||
if err != nil {
|
||||
return fmt.Errorf("writing '%s' to '%s': %w", pe, typ.EventsPath(), err)
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// closeTraceFSProbeEvent removes the [k,u]probe with the given type, group and symbol
|
||||
// from <tracefs>/[k,u]probe_events.
|
||||
func closeTraceFSProbeEvent(typ probeType, group, symbol string) error {
|
||||
f, err := os.OpenFile(typ.EventsPath(), os.O_APPEND|os.O_WRONLY, 0666)
|
||||
if err != nil {
|
||||
return fmt.Errorf("error opening %s: %w", typ.EventsPath(), err)
|
||||
}
|
||||
defer f.Close()
|
||||
|
||||
// See [k,u]probe_events syntax above. The probe type does not need to be specified
|
||||
// for removals.
|
||||
pe := fmt.Sprintf("-:%s/%s", group, sanitizeSymbol(symbol))
|
||||
if _, err = f.WriteString(pe); err != nil {
|
||||
return fmt.Errorf("writing '%s' to '%s': %w", pe, typ.EventsPath(), err)
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// randomGroup generates a pseudorandom string for use as a tracefs group name.
|
||||
// Returns an error when the output string would exceed 63 characters (kernel
|
||||
// limitation), when rand.Read() fails or when prefix contains characters not
|
||||
// allowed by isValidTraceID.
|
||||
func randomGroup(prefix string) (string, error) {
|
||||
if !isValidTraceID(prefix) {
|
||||
return "", fmt.Errorf("prefix '%s' must be alphanumeric or underscore: %w", prefix, errInvalidInput)
|
||||
}
|
||||
|
||||
b := make([]byte, 8)
|
||||
if _, err := rand.Read(b); err != nil {
|
||||
return "", fmt.Errorf("reading random bytes: %w", err)
|
||||
}
|
||||
|
||||
group := fmt.Sprintf("%s_%x", prefix, b)
|
||||
if len(group) > 63 {
|
||||
return "", fmt.Errorf("group name '%s' cannot be longer than 63 characters: %w", group, errInvalidInput)
|
||||
}
|
||||
|
||||
return group, nil
|
||||
}
|
||||
|
||||
func probePrefix(ret bool) string {
|
||||
if ret {
|
||||
return "r"
|
||||
}
|
||||
return "p"
|
||||
}
|
||||
|
||||
// determineRetprobeBit reads a Performance Monitoring Unit's retprobe bit
|
||||
// from /sys/bus/event_source/devices/<pmu>/format/retprobe.
|
||||
func determineRetprobeBit(typ probeType) (uint64, error) {
|
||||
p := filepath.Join("/sys/bus/event_source/devices/", typ.String(), "/format/retprobe")
|
||||
|
||||
data, err := os.ReadFile(p)
|
||||
if err != nil {
|
||||
return 0, err
|
||||
}
|
||||
|
||||
var rp uint64
|
||||
n, err := fmt.Sscanf(string(bytes.TrimSpace(data)), "config:%d", &rp)
|
||||
if err != nil {
|
||||
return 0, fmt.Errorf("parse retprobe bit: %w", err)
|
||||
}
|
||||
if n != 1 {
|
||||
return 0, fmt.Errorf("parse retprobe bit: expected 1 item, got %d", n)
|
||||
}
|
||||
|
||||
return rp, nil
|
||||
}
|
||||
|
||||
func kretprobeBit() (uint64, error) {
|
||||
kprobeRetprobeBit.once.Do(func() {
|
||||
kprobeRetprobeBit.value, kprobeRetprobeBit.err = determineRetprobeBit(kprobeType)
|
||||
})
|
||||
return kprobeRetprobeBit.value, kprobeRetprobeBit.err
|
||||
}
|
||||
|
||||
// kprobeToken creates the SYM[+offs] token for the tracefs api.
|
||||
func kprobeToken(args probeArgs) string {
|
||||
po := args.symbol
|
||||
|
||||
if args.offset != 0 {
|
||||
po += fmt.Sprintf("+%#x", args.offset)
|
||||
}
|
||||
|
||||
return po
|
||||
}
|
|
@ -1,11 +1,14 @@
|
|||
package link
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"encoding/binary"
|
||||
"fmt"
|
||||
"unsafe"
|
||||
|
||||
"github.com/cilium/ebpf"
|
||||
"github.com/cilium/ebpf/btf"
|
||||
"github.com/cilium/ebpf/internal"
|
||||
"github.com/cilium/ebpf/internal/sys"
|
||||
)
|
||||
|
||||
var ErrNotSupported = internal.ErrNotSupported
|
||||
|
@ -22,19 +25,65 @@ type Link interface {
|
|||
// May return an error wrapping ErrNotSupported.
|
||||
Pin(string) error
|
||||
|
||||
// Undo a previous call to Pin.
|
||||
//
|
||||
// May return an error wrapping ErrNotSupported.
|
||||
Unpin() error
|
||||
|
||||
// Close frees resources.
|
||||
//
|
||||
// The link will be broken unless it has been pinned. A link
|
||||
// may continue past the lifetime of the process if Close is
|
||||
// The link will be broken unless it has been successfully pinned.
|
||||
// A link may continue past the lifetime of the process if Close is
|
||||
// not called.
|
||||
Close() error
|
||||
|
||||
// Info returns metadata on a link.
|
||||
//
|
||||
// May return an error wrapping ErrNotSupported.
|
||||
Info() (*Info, error)
|
||||
|
||||
// Prevent external users from implementing this interface.
|
||||
isLink()
|
||||
}
|
||||
|
||||
// LoadPinnedLink loads a link that was persisted into a bpffs.
|
||||
func LoadPinnedLink(fileName string, opts *ebpf.LoadPinOptions) (Link, error) {
|
||||
raw, err := loadPinnedRawLink(fileName, opts)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return wrapRawLink(raw)
|
||||
}
|
||||
|
||||
// wrap a RawLink in a more specific type if possible.
|
||||
//
|
||||
// The function takes ownership of raw and closes it on error.
|
||||
func wrapRawLink(raw *RawLink) (Link, error) {
|
||||
info, err := raw.Info()
|
||||
if err != nil {
|
||||
raw.Close()
|
||||
return nil, err
|
||||
}
|
||||
|
||||
switch info.Type {
|
||||
case RawTracepointType:
|
||||
return &rawTracepoint{*raw}, nil
|
||||
case TracingType:
|
||||
return &tracing{*raw}, nil
|
||||
case CgroupType:
|
||||
return &linkCgroup{*raw}, nil
|
||||
case IterType:
|
||||
return &Iter{*raw}, nil
|
||||
case NetNsType:
|
||||
return &NetNsLink{*raw}, nil
|
||||
default:
|
||||
return raw, nil
|
||||
}
|
||||
}
|
||||
|
||||
// ID uniquely identifies a BPF link.
|
||||
type ID uint32
|
||||
type ID = sys.LinkID
|
||||
|
||||
// RawLinkOptions control the creation of a raw link.
|
||||
type RawLinkOptions struct {
|
||||
|
@ -44,13 +93,55 @@ type RawLinkOptions struct {
|
|||
Program *ebpf.Program
|
||||
// Attach must match the attach type of Program.
|
||||
Attach ebpf.AttachType
|
||||
// BTF is the BTF of the attachment target.
|
||||
BTF btf.TypeID
|
||||
// Flags control the attach behaviour.
|
||||
Flags uint32
|
||||
}
|
||||
|
||||
// RawLinkInfo contains metadata on a link.
|
||||
type RawLinkInfo struct {
|
||||
// Info contains metadata on a link.
|
||||
type Info struct {
|
||||
Type Type
|
||||
ID ID
|
||||
Program ebpf.ProgramID
|
||||
extra interface{}
|
||||
}
|
||||
|
||||
type TracingInfo sys.TracingLinkInfo
|
||||
type CgroupInfo sys.CgroupLinkInfo
|
||||
type NetNsInfo sys.NetNsLinkInfo
|
||||
type XDPInfo sys.XDPLinkInfo
|
||||
|
||||
// Tracing returns tracing type-specific link info.
|
||||
//
|
||||
// Returns nil if the type-specific link info isn't available.
|
||||
func (r Info) Tracing() *TracingInfo {
|
||||
e, _ := r.extra.(*TracingInfo)
|
||||
return e
|
||||
}
|
||||
|
||||
// Cgroup returns cgroup type-specific link info.
|
||||
//
|
||||
// Returns nil if the type-specific link info isn't available.
|
||||
func (r Info) Cgroup() *CgroupInfo {
|
||||
e, _ := r.extra.(*CgroupInfo)
|
||||
return e
|
||||
}
|
||||
|
||||
// NetNs returns netns type-specific link info.
|
||||
//
|
||||
// Returns nil if the type-specific link info isn't available.
|
||||
func (r Info) NetNs() *NetNsInfo {
|
||||
e, _ := r.extra.(*NetNsInfo)
|
||||
return e
|
||||
}
|
||||
|
||||
// ExtraNetNs returns XDP type-specific link info.
|
||||
//
|
||||
// Returns nil if the type-specific link info isn't available.
|
||||
func (r Info) XDP() *XDPInfo {
|
||||
e, _ := r.extra.(*XDPInfo)
|
||||
return e
|
||||
}
|
||||
|
||||
// RawLink is the low-level API to bpf_link.
|
||||
|
@ -58,7 +149,8 @@ type RawLinkInfo struct {
|
|||
// You should consider using the higher level interfaces in this
|
||||
// package instead.
|
||||
type RawLink struct {
|
||||
fd *internal.FD
|
||||
fd *sys.FD
|
||||
pinnedPath string
|
||||
}
|
||||
|
||||
// AttachRawLink creates a raw link.
|
||||
|
@ -68,66 +160,46 @@ func AttachRawLink(opts RawLinkOptions) (*RawLink, error) {
|
|||
}
|
||||
|
||||
if opts.Target < 0 {
|
||||
return nil, fmt.Errorf("invalid target: %s", internal.ErrClosedFd)
|
||||
return nil, fmt.Errorf("invalid target: %s", sys.ErrClosedFd)
|
||||
}
|
||||
|
||||
progFd := opts.Program.FD()
|
||||
if progFd < 0 {
|
||||
return nil, fmt.Errorf("invalid program: %s", internal.ErrClosedFd)
|
||||
return nil, fmt.Errorf("invalid program: %s", sys.ErrClosedFd)
|
||||
}
|
||||
|
||||
attr := bpfLinkCreateAttr{
|
||||
targetFd: uint32(opts.Target),
|
||||
progFd: uint32(progFd),
|
||||
attachType: opts.Attach,
|
||||
attr := sys.LinkCreateAttr{
|
||||
TargetFd: uint32(opts.Target),
|
||||
ProgFd: uint32(progFd),
|
||||
AttachType: sys.AttachType(opts.Attach),
|
||||
TargetBtfId: uint32(opts.BTF),
|
||||
Flags: opts.Flags,
|
||||
}
|
||||
fd, err := bpfLinkCreate(&attr)
|
||||
fd, err := sys.LinkCreate(&attr)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("can't create link: %s", err)
|
||||
}
|
||||
|
||||
return &RawLink{fd}, nil
|
||||
return &RawLink{fd, ""}, nil
|
||||
}
|
||||
|
||||
// LoadPinnedRawLink loads a persisted link from a bpffs.
|
||||
func LoadPinnedRawLink(fileName string) (*RawLink, error) {
|
||||
return loadPinnedRawLink(fileName, UnspecifiedType)
|
||||
}
|
||||
|
||||
func loadPinnedRawLink(fileName string, typ Type) (*RawLink, error) {
|
||||
fd, err := internal.BPFObjGet(fileName)
|
||||
func loadPinnedRawLink(fileName string, opts *ebpf.LoadPinOptions) (*RawLink, error) {
|
||||
fd, err := sys.ObjGet(&sys.ObjGetAttr{
|
||||
Pathname: sys.NewStringPointer(fileName),
|
||||
FileFlags: opts.Marshal(),
|
||||
})
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("load pinned link: %s", err)
|
||||
return nil, fmt.Errorf("load pinned link: %w", err)
|
||||
}
|
||||
|
||||
link := &RawLink{fd}
|
||||
if typ == UnspecifiedType {
|
||||
return link, nil
|
||||
}
|
||||
|
||||
info, err := link.Info()
|
||||
if err != nil {
|
||||
link.Close()
|
||||
return nil, fmt.Errorf("get pinned link info: %s", err)
|
||||
}
|
||||
|
||||
if info.Type != typ {
|
||||
link.Close()
|
||||
return nil, fmt.Errorf("link type %v doesn't match %v", info.Type, typ)
|
||||
}
|
||||
|
||||
return link, nil
|
||||
return &RawLink{fd, fileName}, nil
|
||||
}
|
||||
|
||||
func (l *RawLink) isLink() {}
|
||||
|
||||
// FD returns the raw file descriptor.
|
||||
func (l *RawLink) FD() int {
|
||||
fd, err := l.fd.Value()
|
||||
if err != nil {
|
||||
return -1
|
||||
}
|
||||
return int(fd)
|
||||
return l.fd.Int()
|
||||
}
|
||||
|
||||
// Close breaks the link.
|
||||
|
@ -142,13 +214,23 @@ func (l *RawLink) Close() error {
|
|||
// Calling Close on a pinned Link will not break the link
|
||||
// until the pin is removed.
|
||||
func (l *RawLink) Pin(fileName string) error {
|
||||
if err := internal.BPFObjPin(fileName, l.fd); err != nil {
|
||||
return fmt.Errorf("can't pin link: %s", err)
|
||||
if err := internal.Pin(l.pinnedPath, fileName, l.fd); err != nil {
|
||||
return err
|
||||
}
|
||||
l.pinnedPath = fileName
|
||||
return nil
|
||||
}
|
||||
|
||||
// Update implements Link.
|
||||
// Unpin implements the Link interface.
|
||||
func (l *RawLink) Unpin() error {
|
||||
if err := internal.Unpin(l.pinnedPath); err != nil {
|
||||
return err
|
||||
}
|
||||
l.pinnedPath = ""
|
||||
return nil
|
||||
}
|
||||
|
||||
// Update implements the Link interface.
|
||||
func (l *RawLink) Update(new *ebpf.Program) error {
|
||||
return l.UpdateArgs(RawLinkUpdateOptions{
|
||||
New: new,
|
||||
|
@ -166,49 +248,66 @@ type RawLinkUpdateOptions struct {
|
|||
func (l *RawLink) UpdateArgs(opts RawLinkUpdateOptions) error {
|
||||
newFd := opts.New.FD()
|
||||
if newFd < 0 {
|
||||
return fmt.Errorf("invalid program: %s", internal.ErrClosedFd)
|
||||
return fmt.Errorf("invalid program: %s", sys.ErrClosedFd)
|
||||
}
|
||||
|
||||
var oldFd int
|
||||
if opts.Old != nil {
|
||||
oldFd = opts.Old.FD()
|
||||
if oldFd < 0 {
|
||||
return fmt.Errorf("invalid replacement program: %s", internal.ErrClosedFd)
|
||||
return fmt.Errorf("invalid replacement program: %s", sys.ErrClosedFd)
|
||||
}
|
||||
}
|
||||
|
||||
linkFd, err := l.fd.Value()
|
||||
if err != nil {
|
||||
return fmt.Errorf("can't update link: %s", err)
|
||||
attr := sys.LinkUpdateAttr{
|
||||
LinkFd: l.fd.Uint(),
|
||||
NewProgFd: uint32(newFd),
|
||||
OldProgFd: uint32(oldFd),
|
||||
Flags: opts.Flags,
|
||||
}
|
||||
|
||||
attr := bpfLinkUpdateAttr{
|
||||
linkFd: linkFd,
|
||||
newProgFd: uint32(newFd),
|
||||
oldProgFd: uint32(oldFd),
|
||||
flags: opts.Flags,
|
||||
}
|
||||
return bpfLinkUpdate(&attr)
|
||||
}
|
||||
|
||||
// struct bpf_link_info
|
||||
type bpfLinkInfo struct {
|
||||
typ uint32
|
||||
id uint32
|
||||
prog_id uint32
|
||||
return sys.LinkUpdate(&attr)
|
||||
}
|
||||
|
||||
// Info returns metadata about the link.
|
||||
func (l *RawLink) Info() (*RawLinkInfo, error) {
|
||||
var info bpfLinkInfo
|
||||
err := internal.BPFObjGetInfoByFD(l.fd, unsafe.Pointer(&info), unsafe.Sizeof(info))
|
||||
if err != nil {
|
||||
func (l *RawLink) Info() (*Info, error) {
|
||||
var info sys.LinkInfo
|
||||
|
||||
if err := sys.ObjInfo(l.fd, &info); err != nil {
|
||||
return nil, fmt.Errorf("link info: %s", err)
|
||||
}
|
||||
|
||||
return &RawLinkInfo{
|
||||
Type(info.typ),
|
||||
ID(info.id),
|
||||
ebpf.ProgramID(info.prog_id),
|
||||
var extra interface{}
|
||||
switch info.Type {
|
||||
case CgroupType:
|
||||
extra = &CgroupInfo{}
|
||||
case IterType:
|
||||
// not supported
|
||||
case NetNsType:
|
||||
extra = &NetNsInfo{}
|
||||
case RawTracepointType:
|
||||
// not supported
|
||||
case TracingType:
|
||||
extra = &TracingInfo{}
|
||||
case XDPType:
|
||||
extra = &XDPInfo{}
|
||||
case PerfEventType:
|
||||
// no extra
|
||||
default:
|
||||
return nil, fmt.Errorf("unknown link info type: %d", info.Type)
|
||||
}
|
||||
|
||||
if info.Type != RawTracepointType && info.Type != IterType && info.Type != PerfEventType {
|
||||
buf := bytes.NewReader(info.Extra[:])
|
||||
err := binary.Read(buf, internal.NativeEndian, extra)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("can not read extra link info: %w", err)
|
||||
}
|
||||
}
|
||||
|
||||
return &Info{
|
||||
info.Type,
|
||||
info.Id,
|
||||
ebpf.ProgramID(info.ProgId),
|
||||
extra,
|
||||
}, nil
|
||||
}
|
||||
|
|
|
@ -6,14 +6,9 @@ import (
|
|||
"github.com/cilium/ebpf"
|
||||
)
|
||||
|
||||
// NetNsInfo contains metadata about a network namespace link.
|
||||
type NetNsInfo struct {
|
||||
RawLinkInfo
|
||||
}
|
||||
|
||||
// NetNsLink is a program attached to a network namespace.
|
||||
type NetNsLink struct {
|
||||
*RawLink
|
||||
RawLink
|
||||
}
|
||||
|
||||
// AttachNetNs attaches a program to a network namespace.
|
||||
|
@ -37,24 +32,5 @@ func AttachNetNs(ns int, prog *ebpf.Program) (*NetNsLink, error) {
|
|||
return nil, err
|
||||
}
|
||||
|
||||
return &NetNsLink{link}, nil
|
||||
}
|
||||
|
||||
// LoadPinnedNetNs loads a network namespace link from bpffs.
|
||||
func LoadPinnedNetNs(fileName string) (*NetNsLink, error) {
|
||||
link, err := loadPinnedRawLink(fileName, NetNsType)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return &NetNsLink{link}, nil
|
||||
}
|
||||
|
||||
// Info returns information about the link.
|
||||
func (nns *NetNsLink) Info() (*NetNsInfo, error) {
|
||||
info, err := nns.RawLink.Info()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return &NetNsInfo{*info}, nil
|
||||
return &NetNsLink{*link}, nil
|
||||
}
|
||||
|
|
|
@ -0,0 +1,394 @@
|
|||
package link
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"errors"
|
||||
"fmt"
|
||||
"os"
|
||||
"path/filepath"
|
||||
"runtime"
|
||||
"strconv"
|
||||
"strings"
|
||||
"unsafe"
|
||||
|
||||
"github.com/cilium/ebpf"
|
||||
"github.com/cilium/ebpf/asm"
|
||||
"github.com/cilium/ebpf/internal"
|
||||
"github.com/cilium/ebpf/internal/sys"
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
// Getting the terminology right is usually the hardest part. For posterity and
|
||||
// for staying sane during implementation:
|
||||
//
|
||||
// - trace event: Representation of a kernel runtime hook. Filesystem entries
|
||||
// under <tracefs>/events. Can be tracepoints (static), kprobes or uprobes.
|
||||
// Can be instantiated into perf events (see below).
|
||||
// - tracepoint: A predetermined hook point in the kernel. Exposed as trace
|
||||
// events in (sub)directories under <tracefs>/events. Cannot be closed or
|
||||
// removed, they are static.
|
||||
// - k(ret)probe: Ephemeral trace events based on entry or exit points of
|
||||
// exported kernel symbols. kprobe-based (tracefs) trace events can be
|
||||
// created system-wide by writing to the <tracefs>/kprobe_events file, or
|
||||
// they can be scoped to the current process by creating PMU perf events.
|
||||
// - u(ret)probe: Ephemeral trace events based on user provides ELF binaries
|
||||
// and offsets. uprobe-based (tracefs) trace events can be
|
||||
// created system-wide by writing to the <tracefs>/uprobe_events file, or
|
||||
// they can be scoped to the current process by creating PMU perf events.
|
||||
// - perf event: An object instantiated based on an existing trace event or
|
||||
// kernel symbol. Referred to by fd in userspace.
|
||||
// Exactly one eBPF program can be attached to a perf event. Multiple perf
|
||||
// events can be created from a single trace event. Closing a perf event
|
||||
// stops any further invocations of the attached eBPF program.
|
||||
|
||||
var (
|
||||
tracefsPath = "/sys/kernel/debug/tracing"
|
||||
|
||||
errInvalidInput = errors.New("invalid input")
|
||||
)
|
||||
|
||||
const (
|
||||
perfAllThreads = -1
|
||||
)
|
||||
|
||||
type perfEventType uint8
|
||||
|
||||
const (
|
||||
tracepointEvent perfEventType = iota
|
||||
kprobeEvent
|
||||
kretprobeEvent
|
||||
uprobeEvent
|
||||
uretprobeEvent
|
||||
)
|
||||
|
||||
// A perfEvent represents a perf event kernel object. Exactly one eBPF program
|
||||
// can be attached to it. It is created based on a tracefs trace event or a
|
||||
// Performance Monitoring Unit (PMU).
|
||||
type perfEvent struct {
|
||||
// The event type determines the types of programs that can be attached.
|
||||
typ perfEventType
|
||||
|
||||
// Group and name of the tracepoint/kprobe/uprobe.
|
||||
group string
|
||||
name string
|
||||
|
||||
// PMU event ID read from sysfs. Valid IDs are non-zero.
|
||||
pmuID uint64
|
||||
// ID of the trace event read from tracefs. Valid IDs are non-zero.
|
||||
tracefsID uint64
|
||||
|
||||
// User provided arbitrary value.
|
||||
cookie uint64
|
||||
|
||||
// This is the perf event FD.
|
||||
fd *sys.FD
|
||||
}
|
||||
|
||||
func (pe *perfEvent) Close() error {
|
||||
if err := pe.fd.Close(); err != nil {
|
||||
return fmt.Errorf("closing perf event fd: %w", err)
|
||||
}
|
||||
|
||||
switch pe.typ {
|
||||
case kprobeEvent, kretprobeEvent:
|
||||
// Clean up kprobe tracefs entry.
|
||||
if pe.tracefsID != 0 {
|
||||
return closeTraceFSProbeEvent(kprobeType, pe.group, pe.name)
|
||||
}
|
||||
case uprobeEvent, uretprobeEvent:
|
||||
// Clean up uprobe tracefs entry.
|
||||
if pe.tracefsID != 0 {
|
||||
return closeTraceFSProbeEvent(uprobeType, pe.group, pe.name)
|
||||
}
|
||||
case tracepointEvent:
|
||||
// Tracepoint trace events don't hold any extra resources.
|
||||
return nil
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// perfEventLink represents a bpf perf link.
|
||||
type perfEventLink struct {
|
||||
RawLink
|
||||
pe *perfEvent
|
||||
}
|
||||
|
||||
func (pl *perfEventLink) isLink() {}
|
||||
|
||||
// Pinning requires the underlying perf event FD to stay open.
|
||||
//
|
||||
// | PerfEvent FD | BpfLink FD | Works |
|
||||
// |--------------|------------|-------|
|
||||
// | Open | Open | Yes |
|
||||
// | Closed | Open | No |
|
||||
// | Open | Closed | No (Pin() -> EINVAL) |
|
||||
// | Closed | Closed | No (Pin() -> EINVAL) |
|
||||
//
|
||||
// There is currently no pretty way to recover the perf event FD
|
||||
// when loading a pinned link, so leave as not supported for now.
|
||||
func (pl *perfEventLink) Pin(string) error {
|
||||
return fmt.Errorf("perf event link pin: %w", ErrNotSupported)
|
||||
}
|
||||
|
||||
func (pl *perfEventLink) Unpin() error {
|
||||
return fmt.Errorf("perf event link unpin: %w", ErrNotSupported)
|
||||
}
|
||||
|
||||
func (pl *perfEventLink) Close() error {
|
||||
if err := pl.pe.Close(); err != nil {
|
||||
return fmt.Errorf("perf event link close: %w", err)
|
||||
}
|
||||
return pl.fd.Close()
|
||||
}
|
||||
|
||||
func (pl *perfEventLink) Update(prog *ebpf.Program) error {
|
||||
return fmt.Errorf("perf event link update: %w", ErrNotSupported)
|
||||
}
|
||||
|
||||
// perfEventIoctl implements Link and handles the perf event lifecycle
|
||||
// via ioctl().
|
||||
type perfEventIoctl struct {
|
||||
*perfEvent
|
||||
}
|
||||
|
||||
func (pi *perfEventIoctl) isLink() {}
|
||||
|
||||
// Since 4.15 (e87c6bc3852b "bpf: permit multiple bpf attachments for a single perf event"),
|
||||
// calling PERF_EVENT_IOC_SET_BPF appends the given program to a prog_array
|
||||
// owned by the perf event, which means multiple programs can be attached
|
||||
// simultaneously.
|
||||
//
|
||||
// Before 4.15, calling PERF_EVENT_IOC_SET_BPF more than once on a perf event
|
||||
// returns EEXIST.
|
||||
//
|
||||
// Detaching a program from a perf event is currently not possible, so a
|
||||
// program replacement mechanism cannot be implemented for perf events.
|
||||
func (pi *perfEventIoctl) Update(prog *ebpf.Program) error {
|
||||
return fmt.Errorf("perf event ioctl update: %w", ErrNotSupported)
|
||||
}
|
||||
|
||||
func (pi *perfEventIoctl) Pin(string) error {
|
||||
return fmt.Errorf("perf event ioctl pin: %w", ErrNotSupported)
|
||||
}
|
||||
|
||||
func (pi *perfEventIoctl) Unpin() error {
|
||||
return fmt.Errorf("perf event ioctl unpin: %w", ErrNotSupported)
|
||||
}
|
||||
|
||||
func (pi *perfEventIoctl) Info() (*Info, error) {
|
||||
return nil, fmt.Errorf("perf event ioctl info: %w", ErrNotSupported)
|
||||
}
|
||||
|
||||
// attach the given eBPF prog to the perf event stored in pe.
|
||||
// pe must contain a valid perf event fd.
|
||||
// prog's type must match the program type stored in pe.
|
||||
func attachPerfEvent(pe *perfEvent, prog *ebpf.Program) (Link, error) {
|
||||
if prog == nil {
|
||||
return nil, errors.New("cannot attach a nil program")
|
||||
}
|
||||
if prog.FD() < 0 {
|
||||
return nil, fmt.Errorf("invalid program: %w", sys.ErrClosedFd)
|
||||
}
|
||||
|
||||
switch pe.typ {
|
||||
case kprobeEvent, kretprobeEvent, uprobeEvent, uretprobeEvent:
|
||||
if t := prog.Type(); t != ebpf.Kprobe {
|
||||
return nil, fmt.Errorf("invalid program type (expected %s): %s", ebpf.Kprobe, t)
|
||||
}
|
||||
case tracepointEvent:
|
||||
if t := prog.Type(); t != ebpf.TracePoint {
|
||||
return nil, fmt.Errorf("invalid program type (expected %s): %s", ebpf.TracePoint, t)
|
||||
}
|
||||
default:
|
||||
return nil, fmt.Errorf("unknown perf event type: %d", pe.typ)
|
||||
}
|
||||
|
||||
if err := haveBPFLinkPerfEvent(); err == nil {
|
||||
return attachPerfEventLink(pe, prog)
|
||||
}
|
||||
return attachPerfEventIoctl(pe, prog)
|
||||
}
|
||||
|
||||
func attachPerfEventIoctl(pe *perfEvent, prog *ebpf.Program) (*perfEventIoctl, error) {
|
||||
if pe.cookie != 0 {
|
||||
return nil, fmt.Errorf("cookies are not supported: %w", ErrNotSupported)
|
||||
}
|
||||
|
||||
// Assign the eBPF program to the perf event.
|
||||
err := unix.IoctlSetInt(pe.fd.Int(), unix.PERF_EVENT_IOC_SET_BPF, prog.FD())
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("setting perf event bpf program: %w", err)
|
||||
}
|
||||
|
||||
// PERF_EVENT_IOC_ENABLE and _DISABLE ignore their given values.
|
||||
if err := unix.IoctlSetInt(pe.fd.Int(), unix.PERF_EVENT_IOC_ENABLE, 0); err != nil {
|
||||
return nil, fmt.Errorf("enable perf event: %s", err)
|
||||
}
|
||||
|
||||
pi := &perfEventIoctl{pe}
|
||||
|
||||
// Close the perf event when its reference is lost to avoid leaking system resources.
|
||||
runtime.SetFinalizer(pi, (*perfEventIoctl).Close)
|
||||
return pi, nil
|
||||
}
|
||||
|
||||
// Use the bpf api to attach the perf event (BPF_LINK_TYPE_PERF_EVENT, 5.15+).
|
||||
//
|
||||
// https://github.com/torvalds/linux/commit/b89fbfbb854c9afc3047e8273cc3a694650b802e
|
||||
func attachPerfEventLink(pe *perfEvent, prog *ebpf.Program) (*perfEventLink, error) {
|
||||
fd, err := sys.LinkCreatePerfEvent(&sys.LinkCreatePerfEventAttr{
|
||||
ProgFd: uint32(prog.FD()),
|
||||
TargetFd: pe.fd.Uint(),
|
||||
AttachType: sys.BPF_PERF_EVENT,
|
||||
BpfCookie: pe.cookie,
|
||||
})
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("cannot create bpf perf link: %v", err)
|
||||
}
|
||||
|
||||
pl := &perfEventLink{RawLink{fd: fd}, pe}
|
||||
|
||||
// Close the perf event when its reference is lost to avoid leaking system resources.
|
||||
runtime.SetFinalizer(pl, (*perfEventLink).Close)
|
||||
return pl, nil
|
||||
}
|
||||
|
||||
// unsafeStringPtr returns an unsafe.Pointer to a NUL-terminated copy of str.
|
||||
func unsafeStringPtr(str string) (unsafe.Pointer, error) {
|
||||
p, err := unix.BytePtrFromString(str)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return unsafe.Pointer(p), nil
|
||||
}
|
||||
|
||||
// getTraceEventID reads a trace event's ID from tracefs given its group and name.
|
||||
// The kernel requires group and name to be alphanumeric or underscore.
|
||||
//
|
||||
// name automatically has its invalid symbols converted to underscores so the caller
|
||||
// can pass a raw symbol name, e.g. a kernel symbol containing dots.
|
||||
func getTraceEventID(group, name string) (uint64, error) {
|
||||
name = sanitizeSymbol(name)
|
||||
tid, err := uint64FromFile(tracefsPath, "events", group, name, "id")
|
||||
if errors.Is(err, os.ErrNotExist) {
|
||||
return 0, fmt.Errorf("trace event %s/%s: %w", group, name, os.ErrNotExist)
|
||||
}
|
||||
if err != nil {
|
||||
return 0, fmt.Errorf("reading trace event ID of %s/%s: %w", group, name, err)
|
||||
}
|
||||
|
||||
return tid, nil
|
||||
}
|
||||
|
||||
// getPMUEventType reads a Performance Monitoring Unit's type (numeric identifier)
|
||||
// from /sys/bus/event_source/devices/<pmu>/type.
|
||||
//
|
||||
// Returns ErrNotSupported if the pmu type is not supported.
|
||||
func getPMUEventType(typ probeType) (uint64, error) {
|
||||
et, err := uint64FromFile("/sys/bus/event_source/devices", typ.String(), "type")
|
||||
if errors.Is(err, os.ErrNotExist) {
|
||||
return 0, fmt.Errorf("pmu type %s: %w", typ, ErrNotSupported)
|
||||
}
|
||||
if err != nil {
|
||||
return 0, fmt.Errorf("reading pmu type %s: %w", typ, err)
|
||||
}
|
||||
|
||||
return et, nil
|
||||
}
|
||||
|
||||
// openTracepointPerfEvent opens a tracepoint-type perf event. System-wide
|
||||
// [k,u]probes created by writing to <tracefs>/[k,u]probe_events are tracepoints
|
||||
// behind the scenes, and can be attached to using these perf events.
|
||||
func openTracepointPerfEvent(tid uint64, pid int) (*sys.FD, error) {
|
||||
attr := unix.PerfEventAttr{
|
||||
Type: unix.PERF_TYPE_TRACEPOINT,
|
||||
Config: tid,
|
||||
Sample_type: unix.PERF_SAMPLE_RAW,
|
||||
Sample: 1,
|
||||
Wakeup: 1,
|
||||
}
|
||||
|
||||
fd, err := unix.PerfEventOpen(&attr, pid, 0, -1, unix.PERF_FLAG_FD_CLOEXEC)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("opening tracepoint perf event: %w", err)
|
||||
}
|
||||
|
||||
return sys.NewFD(fd)
|
||||
}
|
||||
|
||||
// uint64FromFile reads a uint64 from a file. All elements of path are sanitized
|
||||
// and joined onto base. Returns error if base no longer prefixes the path after
|
||||
// joining all components.
|
||||
func uint64FromFile(base string, path ...string) (uint64, error) {
|
||||
l := filepath.Join(path...)
|
||||
p := filepath.Join(base, l)
|
||||
if !strings.HasPrefix(p, base) {
|
||||
return 0, fmt.Errorf("path '%s' attempts to escape base path '%s': %w", l, base, errInvalidInput)
|
||||
}
|
||||
|
||||
data, err := os.ReadFile(p)
|
||||
if err != nil {
|
||||
return 0, fmt.Errorf("reading file %s: %w", p, err)
|
||||
}
|
||||
|
||||
et := bytes.TrimSpace(data)
|
||||
return strconv.ParseUint(string(et), 10, 64)
|
||||
}
|
||||
|
||||
// Probe BPF perf link.
|
||||
//
|
||||
// https://elixir.bootlin.com/linux/v5.16.8/source/kernel/bpf/syscall.c#L4307
|
||||
// https://github.com/torvalds/linux/commit/b89fbfbb854c9afc3047e8273cc3a694650b802e
|
||||
var haveBPFLinkPerfEvent = internal.FeatureTest("bpf_link_perf_event", "5.15", func() error {
|
||||
prog, err := ebpf.NewProgram(&ebpf.ProgramSpec{
|
||||
Name: "probe_bpf_perf_link",
|
||||
Type: ebpf.Kprobe,
|
||||
Instructions: asm.Instructions{
|
||||
asm.Mov.Imm(asm.R0, 0),
|
||||
asm.Return(),
|
||||
},
|
||||
License: "MIT",
|
||||
})
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
defer prog.Close()
|
||||
|
||||
_, err = sys.LinkCreatePerfEvent(&sys.LinkCreatePerfEventAttr{
|
||||
ProgFd: uint32(prog.FD()),
|
||||
AttachType: sys.BPF_PERF_EVENT,
|
||||
})
|
||||
if errors.Is(err, unix.EINVAL) {
|
||||
return internal.ErrNotSupported
|
||||
}
|
||||
if errors.Is(err, unix.EBADF) {
|
||||
return nil
|
||||
}
|
||||
return err
|
||||
})
|
||||
|
||||
// isValidTraceID implements the equivalent of a regex match
|
||||
// against "^[a-zA-Z_][0-9a-zA-Z_]*$".
|
||||
//
|
||||
// Trace event groups, names and kernel symbols must adhere to this set
|
||||
// of characters. Non-empty, first character must not be a number, all
|
||||
// characters must be alphanumeric or underscore.
|
||||
func isValidTraceID(s string) bool {
|
||||
if len(s) < 1 {
|
||||
return false
|
||||
}
|
||||
for i, c := range []byte(s) {
|
||||
switch {
|
||||
case c >= 'a' && c <= 'z':
|
||||
case c >= 'A' && c <= 'Z':
|
||||
case c == '_':
|
||||
case i > 0 && c >= '0' && c <= '9':
|
||||
|
||||
default:
|
||||
return false
|
||||
}
|
||||
}
|
||||
|
||||
return true
|
||||
}
|
|
@ -0,0 +1,25 @@
|
|||
package link
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
"runtime"
|
||||
)
|
||||
|
||||
func platformPrefix(symbol string) string {
|
||||
|
||||
prefix := runtime.GOARCH
|
||||
|
||||
// per https://github.com/golang/go/blob/master/src/go/build/syslist.go
|
||||
switch prefix {
|
||||
case "386":
|
||||
prefix = "ia32"
|
||||
case "amd64", "amd64p32":
|
||||
prefix = "x64"
|
||||
case "arm64", "arm64be":
|
||||
prefix = "arm64"
|
||||
default:
|
||||
return symbol
|
||||
}
|
||||
|
||||
return fmt.Sprintf("__%s_%s", prefix, symbol)
|
||||
}
|
|
@ -4,7 +4,7 @@ import (
|
|||
"fmt"
|
||||
|
||||
"github.com/cilium/ebpf"
|
||||
"github.com/cilium/ebpf/internal"
|
||||
"github.com/cilium/ebpf/internal/sys"
|
||||
)
|
||||
|
||||
type RawAttachProgramOptions struct {
|
||||
|
@ -34,7 +34,7 @@ func RawAttachProgram(opts RawAttachProgramOptions) error {
|
|||
replaceFd = uint32(opts.Replace.FD())
|
||||
}
|
||||
|
||||
attr := internal.BPFProgAttachAttr{
|
||||
attr := sys.ProgAttachAttr{
|
||||
TargetFd: uint32(opts.Target),
|
||||
AttachBpfFd: uint32(opts.Program.FD()),
|
||||
ReplaceBpfFd: replaceFd,
|
||||
|
@ -42,8 +42,8 @@ func RawAttachProgram(opts RawAttachProgramOptions) error {
|
|||
AttachFlags: uint32(opts.Flags),
|
||||
}
|
||||
|
||||
if err := internal.BPFProgAttach(&attr); err != nil {
|
||||
return fmt.Errorf("can't attach program: %s", err)
|
||||
if err := sys.ProgAttach(&attr); err != nil {
|
||||
return fmt.Errorf("can't attach program: %w", err)
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
@ -63,13 +63,13 @@ func RawDetachProgram(opts RawDetachProgramOptions) error {
|
|||
return err
|
||||
}
|
||||
|
||||
attr := internal.BPFProgDetachAttr{
|
||||
attr := sys.ProgDetachAttr{
|
||||
TargetFd: uint32(opts.Target),
|
||||
AttachBpfFd: uint32(opts.Program.FD()),
|
||||
AttachType: uint32(opts.Attach),
|
||||
}
|
||||
if err := internal.BPFProgDetach(&attr); err != nil {
|
||||
return fmt.Errorf("can't detach program: %s", err)
|
||||
if err := sys.ProgDetach(&attr); err != nil {
|
||||
return fmt.Errorf("can't detach program: %w", err)
|
||||
}
|
||||
|
||||
return nil
|
||||
|
|
|
@ -1,10 +1,11 @@
|
|||
package link
|
||||
|
||||
import (
|
||||
"errors"
|
||||
"fmt"
|
||||
|
||||
"github.com/cilium/ebpf"
|
||||
"github.com/cilium/ebpf/internal"
|
||||
"github.com/cilium/ebpf/internal/sys"
|
||||
)
|
||||
|
||||
type RawTracepointOptions struct {
|
||||
|
@ -22,36 +23,65 @@ func AttachRawTracepoint(opts RawTracepointOptions) (Link, error) {
|
|||
return nil, fmt.Errorf("invalid program type %s, expected RawTracepoint(Writable)", t)
|
||||
}
|
||||
if opts.Program.FD() < 0 {
|
||||
return nil, fmt.Errorf("invalid program: %w", internal.ErrClosedFd)
|
||||
return nil, fmt.Errorf("invalid program: %w", sys.ErrClosedFd)
|
||||
}
|
||||
|
||||
fd, err := bpfRawTracepointOpen(&bpfRawTracepointOpenAttr{
|
||||
name: internal.NewStringPointer(opts.Name),
|
||||
fd: uint32(opts.Program.FD()),
|
||||
fd, err := sys.RawTracepointOpen(&sys.RawTracepointOpenAttr{
|
||||
Name: sys.NewStringPointer(opts.Name),
|
||||
ProgFd: uint32(opts.Program.FD()),
|
||||
})
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return &progAttachRawTracepoint{fd: fd}, nil
|
||||
err = haveBPFLink()
|
||||
if errors.Is(err, ErrNotSupported) {
|
||||
// Prior to commit 70ed506c3bbc ("bpf: Introduce pinnable bpf_link abstraction")
|
||||
// raw_tracepoints are just a plain fd.
|
||||
return &simpleRawTracepoint{fd}, nil
|
||||
}
|
||||
|
||||
type progAttachRawTracepoint struct {
|
||||
fd *internal.FD
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
var _ Link = (*progAttachRawTracepoint)(nil)
|
||||
|
||||
func (rt *progAttachRawTracepoint) isLink() {}
|
||||
|
||||
func (rt *progAttachRawTracepoint) Close() error {
|
||||
return rt.fd.Close()
|
||||
return &rawTracepoint{RawLink{fd: fd}}, nil
|
||||
}
|
||||
|
||||
func (rt *progAttachRawTracepoint) Update(_ *ebpf.Program) error {
|
||||
return fmt.Errorf("can't update raw_tracepoint: %w", ErrNotSupported)
|
||||
type simpleRawTracepoint struct {
|
||||
fd *sys.FD
|
||||
}
|
||||
|
||||
func (rt *progAttachRawTracepoint) Pin(_ string) error {
|
||||
return fmt.Errorf("can't pin raw_tracepoint: %w", ErrNotSupported)
|
||||
var _ Link = (*simpleRawTracepoint)(nil)
|
||||
|
||||
func (frt *simpleRawTracepoint) isLink() {}
|
||||
|
||||
func (frt *simpleRawTracepoint) Close() error {
|
||||
return frt.fd.Close()
|
||||
}
|
||||
|
||||
func (frt *simpleRawTracepoint) Update(_ *ebpf.Program) error {
|
||||
return fmt.Errorf("update raw_tracepoint: %w", ErrNotSupported)
|
||||
}
|
||||
|
||||
func (frt *simpleRawTracepoint) Pin(string) error {
|
||||
return fmt.Errorf("pin raw_tracepoint: %w", ErrNotSupported)
|
||||
}
|
||||
|
||||
func (frt *simpleRawTracepoint) Unpin() error {
|
||||
return fmt.Errorf("unpin raw_tracepoint: %w", ErrNotSupported)
|
||||
}
|
||||
|
||||
func (frt *simpleRawTracepoint) Info() (*Info, error) {
|
||||
return nil, fmt.Errorf("can't get raw_tracepoint info: %w", ErrNotSupported)
|
||||
}
|
||||
|
||||
type rawTracepoint struct {
|
||||
RawLink
|
||||
}
|
||||
|
||||
var _ Link = (*rawTracepoint)(nil)
|
||||
|
||||
func (rt *rawTracepoint) Update(_ *ebpf.Program) error {
|
||||
return fmt.Errorf("update raw_tracepoint: %w", ErrNotSupported)
|
||||
}
|
||||
|
|
|
@ -0,0 +1,40 @@
|
|||
package link
|
||||
|
||||
import (
|
||||
"syscall"
|
||||
|
||||
"github.com/cilium/ebpf"
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
// AttachSocketFilter attaches a SocketFilter BPF program to a socket.
|
||||
func AttachSocketFilter(conn syscall.Conn, program *ebpf.Program) error {
|
||||
rawConn, err := conn.SyscallConn()
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
var ssoErr error
|
||||
err = rawConn.Control(func(fd uintptr) {
|
||||
ssoErr = syscall.SetsockoptInt(int(fd), unix.SOL_SOCKET, unix.SO_ATTACH_BPF, program.FD())
|
||||
})
|
||||
if ssoErr != nil {
|
||||
return ssoErr
|
||||
}
|
||||
return err
|
||||
}
|
||||
|
||||
// DetachSocketFilter detaches a SocketFilter BPF program from a socket.
|
||||
func DetachSocketFilter(conn syscall.Conn) error {
|
||||
rawConn, err := conn.SyscallConn()
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
var ssoErr error
|
||||
err = rawConn.Control(func(fd uintptr) {
|
||||
ssoErr = syscall.SetsockoptInt(int(fd), unix.SOL_SOCKET, unix.SO_DETACH_BPF, 0)
|
||||
})
|
||||
if ssoErr != nil {
|
||||
return ssoErr
|
||||
}
|
||||
return err
|
||||
}
|
|
@ -2,34 +2,32 @@ package link
|
|||
|
||||
import (
|
||||
"errors"
|
||||
"unsafe"
|
||||
|
||||
"github.com/cilium/ebpf"
|
||||
"github.com/cilium/ebpf/asm"
|
||||
"github.com/cilium/ebpf/internal"
|
||||
"github.com/cilium/ebpf/internal/sys"
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
// Type is the kind of link.
|
||||
type Type uint32
|
||||
type Type = sys.LinkType
|
||||
|
||||
// Valid link types.
|
||||
//
|
||||
// Equivalent to enum bpf_link_type.
|
||||
const (
|
||||
UnspecifiedType Type = iota
|
||||
RawTracepointType
|
||||
TracingType
|
||||
CgroupType
|
||||
IterType
|
||||
NetNsType
|
||||
XDPType
|
||||
UnspecifiedType = sys.BPF_LINK_TYPE_UNSPEC
|
||||
RawTracepointType = sys.BPF_LINK_TYPE_RAW_TRACEPOINT
|
||||
TracingType = sys.BPF_LINK_TYPE_TRACING
|
||||
CgroupType = sys.BPF_LINK_TYPE_CGROUP
|
||||
IterType = sys.BPF_LINK_TYPE_ITER
|
||||
NetNsType = sys.BPF_LINK_TYPE_NETNS
|
||||
XDPType = sys.BPF_LINK_TYPE_XDP
|
||||
PerfEventType = sys.BPF_LINK_TYPE_PERF_EVENT
|
||||
)
|
||||
|
||||
var haveProgAttach = internal.FeatureTest("BPF_PROG_ATTACH", "4.10", func() error {
|
||||
prog, err := ebpf.NewProgram(&ebpf.ProgramSpec{
|
||||
Type: ebpf.CGroupSKB,
|
||||
AttachType: ebpf.AttachCGroupInetIngress,
|
||||
License: "MIT",
|
||||
Instructions: asm.Instructions{
|
||||
asm.Mov.Imm(asm.R0, 0),
|
||||
|
@ -69,7 +67,7 @@ var haveProgAttachReplace = internal.FeatureTest("BPF_PROG_ATTACH atomic replace
|
|||
// We know that we have BPF_PROG_ATTACH since we can load CGroupSKB programs.
|
||||
// If passing BPF_F_REPLACE gives us EINVAL we know that the feature isn't
|
||||
// present.
|
||||
attr := internal.BPFProgAttachAttr{
|
||||
attr := sys.ProgAttachAttr{
|
||||
// We rely on this being checked after attachFlags.
|
||||
TargetFd: ^uint32(0),
|
||||
AttachBpfFd: uint32(prog.FD()),
|
||||
|
@ -77,7 +75,7 @@ var haveProgAttachReplace = internal.FeatureTest("BPF_PROG_ATTACH atomic replace
|
|||
AttachFlags: uint32(flagReplace),
|
||||
}
|
||||
|
||||
err = internal.BPFProgAttach(&attr)
|
||||
err = sys.ProgAttach(&attr)
|
||||
if errors.Is(err, unix.EINVAL) {
|
||||
return internal.ErrNotSupported
|
||||
}
|
||||
|
@ -87,55 +85,14 @@ var haveProgAttachReplace = internal.FeatureTest("BPF_PROG_ATTACH atomic replace
|
|||
return err
|
||||
})
|
||||
|
||||
type bpfLinkCreateAttr struct {
|
||||
progFd uint32
|
||||
targetFd uint32
|
||||
attachType ebpf.AttachType
|
||||
flags uint32
|
||||
}
|
||||
|
||||
func bpfLinkCreate(attr *bpfLinkCreateAttr) (*internal.FD, error) {
|
||||
ptr, err := internal.BPF(internal.BPF_LINK_CREATE, unsafe.Pointer(attr), unsafe.Sizeof(*attr))
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return internal.NewFD(uint32(ptr)), nil
|
||||
}
|
||||
|
||||
type bpfLinkUpdateAttr struct {
|
||||
linkFd uint32
|
||||
newProgFd uint32
|
||||
flags uint32
|
||||
oldProgFd uint32
|
||||
}
|
||||
|
||||
func bpfLinkUpdate(attr *bpfLinkUpdateAttr) error {
|
||||
_, err := internal.BPF(internal.BPF_LINK_UPDATE, unsafe.Pointer(attr), unsafe.Sizeof(*attr))
|
||||
return err
|
||||
}
|
||||
|
||||
var haveBPFLink = internal.FeatureTest("bpf_link", "5.7", func() error {
|
||||
prog, err := ebpf.NewProgram(&ebpf.ProgramSpec{
|
||||
Type: ebpf.CGroupSKB,
|
||||
AttachType: ebpf.AttachCGroupInetIngress,
|
||||
License: "MIT",
|
||||
Instructions: asm.Instructions{
|
||||
asm.Mov.Imm(asm.R0, 0),
|
||||
asm.Return(),
|
||||
},
|
||||
})
|
||||
if err != nil {
|
||||
return internal.ErrNotSupported
|
||||
}
|
||||
defer prog.Close()
|
||||
|
||||
attr := bpfLinkCreateAttr{
|
||||
attr := sys.LinkCreateAttr{
|
||||
// This is a hopefully invalid file descriptor, which triggers EBADF.
|
||||
targetFd: ^uint32(0),
|
||||
progFd: uint32(prog.FD()),
|
||||
attachType: ebpf.AttachCGroupInetIngress,
|
||||
TargetFd: ^uint32(0),
|
||||
ProgFd: ^uint32(0),
|
||||
AttachType: sys.AttachType(ebpf.AttachCGroupInetIngress),
|
||||
}
|
||||
_, err = bpfLinkCreate(&attr)
|
||||
_, err := sys.LinkCreate(&attr)
|
||||
if errors.Is(err, unix.EINVAL) {
|
||||
return internal.ErrNotSupported
|
||||
}
|
||||
|
@ -144,30 +101,3 @@ var haveBPFLink = internal.FeatureTest("bpf_link", "5.7", func() error {
|
|||
}
|
||||
return err
|
||||
})
|
||||
|
||||
type bpfIterCreateAttr struct {
|
||||
linkFd uint32
|
||||
flags uint32
|
||||
}
|
||||
|
||||
func bpfIterCreate(attr *bpfIterCreateAttr) (*internal.FD, error) {
|
||||
ptr, err := internal.BPF(internal.BPF_ITER_CREATE, unsafe.Pointer(attr), unsafe.Sizeof(*attr))
|
||||
if err == nil {
|
||||
return internal.NewFD(uint32(ptr)), nil
|
||||
}
|
||||
return nil, err
|
||||
}
|
||||
|
||||
type bpfRawTracepointOpenAttr struct {
|
||||
name internal.Pointer
|
||||
fd uint32
|
||||
_ uint32
|
||||
}
|
||||
|
||||
func bpfRawTracepointOpen(attr *bpfRawTracepointOpenAttr) (*internal.FD, error) {
|
||||
ptr, err := internal.BPF(internal.BPF_RAW_TRACEPOINT_OPEN, unsafe.Pointer(attr), unsafe.Sizeof(*attr))
|
||||
if err == nil {
|
||||
return internal.NewFD(uint32(ptr)), nil
|
||||
}
|
||||
return nil, err
|
||||
}
|
||||
|
|
|
@ -0,0 +1,77 @@
|
|||
package link
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
|
||||
"github.com/cilium/ebpf"
|
||||
)
|
||||
|
||||
// TracepointOptions defines additional parameters that will be used
|
||||
// when loading Tracepoints.
|
||||
type TracepointOptions struct {
|
||||
// Arbitrary value that can be fetched from an eBPF program
|
||||
// via `bpf_get_attach_cookie()`.
|
||||
//
|
||||
// Needs kernel 5.15+.
|
||||
Cookie uint64
|
||||
}
|
||||
|
||||
// Tracepoint attaches the given eBPF program to the tracepoint with the given
|
||||
// group and name. See /sys/kernel/debug/tracing/events to find available
|
||||
// tracepoints. The top-level directory is the group, the event's subdirectory
|
||||
// is the name. Example:
|
||||
//
|
||||
// tp, err := Tracepoint("syscalls", "sys_enter_fork", prog, nil)
|
||||
//
|
||||
// Losing the reference to the resulting Link (tp) will close the Tracepoint
|
||||
// and prevent further execution of prog. The Link must be Closed during
|
||||
// program shutdown to avoid leaking system resources.
|
||||
//
|
||||
// Note that attaching eBPF programs to syscalls (sys_enter_*/sys_exit_*) is
|
||||
// only possible as of kernel 4.14 (commit cf5f5ce).
|
||||
func Tracepoint(group, name string, prog *ebpf.Program, opts *TracepointOptions) (Link, error) {
|
||||
if group == "" || name == "" {
|
||||
return nil, fmt.Errorf("group and name cannot be empty: %w", errInvalidInput)
|
||||
}
|
||||
if prog == nil {
|
||||
return nil, fmt.Errorf("prog cannot be nil: %w", errInvalidInput)
|
||||
}
|
||||
if !isValidTraceID(group) || !isValidTraceID(name) {
|
||||
return nil, fmt.Errorf("group and name '%s/%s' must be alphanumeric or underscore: %w", group, name, errInvalidInput)
|
||||
}
|
||||
if prog.Type() != ebpf.TracePoint {
|
||||
return nil, fmt.Errorf("eBPF program type %s is not a Tracepoint: %w", prog.Type(), errInvalidInput)
|
||||
}
|
||||
|
||||
tid, err := getTraceEventID(group, name)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
fd, err := openTracepointPerfEvent(tid, perfAllThreads)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
var cookie uint64
|
||||
if opts != nil {
|
||||
cookie = opts.Cookie
|
||||
}
|
||||
|
||||
pe := &perfEvent{
|
||||
typ: tracepointEvent,
|
||||
group: group,
|
||||
name: name,
|
||||
tracefsID: tid,
|
||||
cookie: cookie,
|
||||
fd: fd,
|
||||
}
|
||||
|
||||
lnk, err := attachPerfEvent(pe, prog)
|
||||
if err != nil {
|
||||
pe.Close()
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return lnk, nil
|
||||
}
|
|
@ -0,0 +1,141 @@
|
|||
package link
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
|
||||
"github.com/cilium/ebpf"
|
||||
"github.com/cilium/ebpf/btf"
|
||||
"github.com/cilium/ebpf/internal/sys"
|
||||
)
|
||||
|
||||
type tracing struct {
|
||||
RawLink
|
||||
}
|
||||
|
||||
func (f *tracing) Update(new *ebpf.Program) error {
|
||||
return fmt.Errorf("tracing update: %w", ErrNotSupported)
|
||||
}
|
||||
|
||||
// AttachFreplace attaches the given eBPF program to the function it replaces.
|
||||
//
|
||||
// The program and name can either be provided at link time, or can be provided
|
||||
// at program load time. If they were provided at load time, they should be nil
|
||||
// and empty respectively here, as they will be ignored by the kernel.
|
||||
// Examples:
|
||||
//
|
||||
// AttachFreplace(dispatcher, "function", replacement)
|
||||
// AttachFreplace(nil, "", replacement)
|
||||
func AttachFreplace(targetProg *ebpf.Program, name string, prog *ebpf.Program) (Link, error) {
|
||||
if (name == "") != (targetProg == nil) {
|
||||
return nil, fmt.Errorf("must provide both or neither of name and targetProg: %w", errInvalidInput)
|
||||
}
|
||||
if prog == nil {
|
||||
return nil, fmt.Errorf("prog cannot be nil: %w", errInvalidInput)
|
||||
}
|
||||
if prog.Type() != ebpf.Extension {
|
||||
return nil, fmt.Errorf("eBPF program type %s is not an Extension: %w", prog.Type(), errInvalidInput)
|
||||
}
|
||||
|
||||
var (
|
||||
target int
|
||||
typeID btf.TypeID
|
||||
)
|
||||
if targetProg != nil {
|
||||
btfHandle, err := targetProg.Handle()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
defer btfHandle.Close()
|
||||
|
||||
spec, err := btfHandle.Spec(nil)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
var function *btf.Func
|
||||
if err := spec.TypeByName(name, &function); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
target = targetProg.FD()
|
||||
typeID, err = spec.TypeID(function)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
}
|
||||
|
||||
link, err := AttachRawLink(RawLinkOptions{
|
||||
Target: target,
|
||||
Program: prog,
|
||||
Attach: ebpf.AttachNone,
|
||||
BTF: typeID,
|
||||
})
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return &tracing{*link}, nil
|
||||
}
|
||||
|
||||
type TracingOptions struct {
|
||||
// Program must be of type Tracing with attach type
|
||||
// AttachTraceFEntry/AttachTraceFExit/AttachModifyReturn or
|
||||
// AttachTraceRawTp.
|
||||
Program *ebpf.Program
|
||||
}
|
||||
|
||||
type LSMOptions struct {
|
||||
// Program must be of type LSM with attach type
|
||||
// AttachLSMMac.
|
||||
Program *ebpf.Program
|
||||
}
|
||||
|
||||
// attachBTFID links all BPF program types (Tracing/LSM) that they attach to a btf_id.
|
||||
func attachBTFID(program *ebpf.Program) (Link, error) {
|
||||
if program.FD() < 0 {
|
||||
return nil, fmt.Errorf("invalid program %w", sys.ErrClosedFd)
|
||||
}
|
||||
|
||||
fd, err := sys.RawTracepointOpen(&sys.RawTracepointOpenAttr{
|
||||
ProgFd: uint32(program.FD()),
|
||||
})
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
raw := RawLink{fd: fd}
|
||||
info, err := raw.Info()
|
||||
if err != nil {
|
||||
raw.Close()
|
||||
return nil, err
|
||||
}
|
||||
|
||||
if info.Type == RawTracepointType {
|
||||
// Sadness upon sadness: a Tracing program with AttachRawTp returns
|
||||
// a raw_tracepoint link. Other types return a tracing link.
|
||||
return &rawTracepoint{raw}, nil
|
||||
}
|
||||
|
||||
return &tracing{RawLink: RawLink{fd: fd}}, nil
|
||||
}
|
||||
|
||||
// AttachTracing links a tracing (fentry/fexit/fmod_ret) BPF program or
|
||||
// a BTF-powered raw tracepoint (tp_btf) BPF Program to a BPF hook defined
|
||||
// in kernel modules.
|
||||
func AttachTracing(opts TracingOptions) (Link, error) {
|
||||
if t := opts.Program.Type(); t != ebpf.Tracing {
|
||||
return nil, fmt.Errorf("invalid program type %s, expected Tracing", t)
|
||||
}
|
||||
|
||||
return attachBTFID(opts.Program)
|
||||
}
|
||||
|
||||
// AttachLSM links a Linux security module (LSM) BPF Program to a BPF
|
||||
// hook defined in kernel modules.
|
||||
func AttachLSM(opts LSMOptions) (Link, error) {
|
||||
if t := opts.Program.Type(); t != ebpf.LSM {
|
||||
return nil, fmt.Errorf("invalid program type %s, expected LSM", t)
|
||||
}
|
||||
|
||||
return attachBTFID(opts.Program)
|
||||
}
|
|
@ -0,0 +1,373 @@
|
|||
package link
|
||||
|
||||
import (
|
||||
"debug/elf"
|
||||
"errors"
|
||||
"fmt"
|
||||
"os"
|
||||
"path/filepath"
|
||||
"strings"
|
||||
"sync"
|
||||
|
||||
"github.com/cilium/ebpf"
|
||||
"github.com/cilium/ebpf/internal"
|
||||
)
|
||||
|
||||
var (
|
||||
uprobeEventsPath = filepath.Join(tracefsPath, "uprobe_events")
|
||||
|
||||
uprobeRetprobeBit = struct {
|
||||
once sync.Once
|
||||
value uint64
|
||||
err error
|
||||
}{}
|
||||
|
||||
uprobeRefCtrOffsetPMUPath = "/sys/bus/event_source/devices/uprobe/format/ref_ctr_offset"
|
||||
// elixir.bootlin.com/linux/v5.15-rc7/source/kernel/events/core.c#L9799
|
||||
uprobeRefCtrOffsetShift = 32
|
||||
haveRefCtrOffsetPMU = internal.FeatureTest("RefCtrOffsetPMU", "4.20", func() error {
|
||||
_, err := os.Stat(uprobeRefCtrOffsetPMUPath)
|
||||
if err != nil {
|
||||
return internal.ErrNotSupported
|
||||
}
|
||||
return nil
|
||||
})
|
||||
|
||||
// ErrNoSymbol indicates that the given symbol was not found
|
||||
// in the ELF symbols table.
|
||||
ErrNoSymbol = errors.New("not found")
|
||||
)
|
||||
|
||||
// Executable defines an executable program on the filesystem.
|
||||
type Executable struct {
|
||||
// Path of the executable on the filesystem.
|
||||
path string
|
||||
// Parsed ELF and dynamic symbols' addresses.
|
||||
addresses map[string]uint64
|
||||
}
|
||||
|
||||
// UprobeOptions defines additional parameters that will be used
|
||||
// when loading Uprobes.
|
||||
type UprobeOptions struct {
|
||||
// Symbol address. Must be provided in case of external symbols (shared libs).
|
||||
// If set, overrides the address eventually parsed from the executable.
|
||||
Address uint64
|
||||
// The offset relative to given symbol. Useful when tracing an arbitrary point
|
||||
// inside the frame of given symbol.
|
||||
//
|
||||
// Note: this field changed from being an absolute offset to being relative
|
||||
// to Address.
|
||||
Offset uint64
|
||||
// Only set the uprobe on the given process ID. Useful when tracing
|
||||
// shared library calls or programs that have many running instances.
|
||||
PID int
|
||||
// Automatically manage SDT reference counts (semaphores).
|
||||
//
|
||||
// If this field is set, the Kernel will increment/decrement the
|
||||
// semaphore located in the process memory at the provided address on
|
||||
// probe attach/detach.
|
||||
//
|
||||
// See also:
|
||||
// sourceware.org/systemtap/wiki/UserSpaceProbeImplementation (Semaphore Handling)
|
||||
// github.com/torvalds/linux/commit/1cc33161a83d
|
||||
// github.com/torvalds/linux/commit/a6ca88b241d5
|
||||
RefCtrOffset uint64
|
||||
// Arbitrary value that can be fetched from an eBPF program
|
||||
// via `bpf_get_attach_cookie()`.
|
||||
//
|
||||
// Needs kernel 5.15+.
|
||||
Cookie uint64
|
||||
}
|
||||
|
||||
// To open a new Executable, use:
|
||||
//
|
||||
// OpenExecutable("/bin/bash")
|
||||
//
|
||||
// The returned value can then be used to open Uprobe(s).
|
||||
func OpenExecutable(path string) (*Executable, error) {
|
||||
if path == "" {
|
||||
return nil, fmt.Errorf("path cannot be empty")
|
||||
}
|
||||
|
||||
f, err := os.Open(path)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("open file '%s': %w", path, err)
|
||||
}
|
||||
defer f.Close()
|
||||
|
||||
se, err := internal.NewSafeELFFile(f)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("parse ELF file: %w", err)
|
||||
}
|
||||
|
||||
if se.Type != elf.ET_EXEC && se.Type != elf.ET_DYN {
|
||||
// ELF is not an executable or a shared object.
|
||||
return nil, errors.New("the given file is not an executable or a shared object")
|
||||
}
|
||||
|
||||
ex := Executable{
|
||||
path: path,
|
||||
addresses: make(map[string]uint64),
|
||||
}
|
||||
|
||||
if err := ex.load(se); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return &ex, nil
|
||||
}
|
||||
|
||||
func (ex *Executable) load(f *internal.SafeELFFile) error {
|
||||
syms, err := f.Symbols()
|
||||
if err != nil && !errors.Is(err, elf.ErrNoSymbols) {
|
||||
return err
|
||||
}
|
||||
|
||||
dynsyms, err := f.DynamicSymbols()
|
||||
if err != nil && !errors.Is(err, elf.ErrNoSymbols) {
|
||||
return err
|
||||
}
|
||||
|
||||
syms = append(syms, dynsyms...)
|
||||
|
||||
for _, s := range syms {
|
||||
if elf.ST_TYPE(s.Info) != elf.STT_FUNC {
|
||||
// Symbol not associated with a function or other executable code.
|
||||
continue
|
||||
}
|
||||
|
||||
address := s.Value
|
||||
|
||||
// Loop over ELF segments.
|
||||
for _, prog := range f.Progs {
|
||||
// Skip uninteresting segments.
|
||||
if prog.Type != elf.PT_LOAD || (prog.Flags&elf.PF_X) == 0 {
|
||||
continue
|
||||
}
|
||||
|
||||
if prog.Vaddr <= s.Value && s.Value < (prog.Vaddr+prog.Memsz) {
|
||||
// If the symbol value is contained in the segment, calculate
|
||||
// the symbol offset.
|
||||
//
|
||||
// fn symbol offset = fn symbol VA - .text VA + .text offset
|
||||
//
|
||||
// stackoverflow.com/a/40249502
|
||||
address = s.Value - prog.Vaddr + prog.Off
|
||||
break
|
||||
}
|
||||
}
|
||||
|
||||
ex.addresses[s.Name] = address
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// address calculates the address of a symbol in the executable.
|
||||
//
|
||||
// opts must not be nil.
|
||||
func (ex *Executable) address(symbol string, opts *UprobeOptions) (uint64, error) {
|
||||
if opts.Address > 0 {
|
||||
return opts.Address + opts.Offset, nil
|
||||
}
|
||||
|
||||
address, ok := ex.addresses[symbol]
|
||||
if !ok {
|
||||
return 0, fmt.Errorf("symbol %s: %w", symbol, ErrNoSymbol)
|
||||
}
|
||||
|
||||
// Symbols with location 0 from section undef are shared library calls and
|
||||
// are relocated before the binary is executed. Dynamic linking is not
|
||||
// implemented by the library, so mark this as unsupported for now.
|
||||
//
|
||||
// Since only offset values are stored and not elf.Symbol, if the value is 0,
|
||||
// assume it's an external symbol.
|
||||
if address == 0 {
|
||||
return 0, fmt.Errorf("cannot resolve %s library call '%s': %w "+
|
||||
"(consider providing UprobeOptions.Address)", ex.path, symbol, ErrNotSupported)
|
||||
}
|
||||
|
||||
return address + opts.Offset, nil
|
||||
}
|
||||
|
||||
// Uprobe attaches the given eBPF program to a perf event that fires when the
|
||||
// given symbol starts executing in the given Executable.
|
||||
// For example, /bin/bash::main():
|
||||
//
|
||||
// ex, _ = OpenExecutable("/bin/bash")
|
||||
// ex.Uprobe("main", prog, nil)
|
||||
//
|
||||
// When using symbols which belongs to shared libraries,
|
||||
// an offset must be provided via options:
|
||||
//
|
||||
// up, err := ex.Uprobe("main", prog, &UprobeOptions{Offset: 0x123})
|
||||
//
|
||||
// Note: Setting the Offset field in the options supersedes the symbol's offset.
|
||||
//
|
||||
// Losing the reference to the resulting Link (up) will close the Uprobe
|
||||
// and prevent further execution of prog. The Link must be Closed during
|
||||
// program shutdown to avoid leaking system resources.
|
||||
//
|
||||
// Functions provided by shared libraries can currently not be traced and
|
||||
// will result in an ErrNotSupported.
|
||||
func (ex *Executable) Uprobe(symbol string, prog *ebpf.Program, opts *UprobeOptions) (Link, error) {
|
||||
u, err := ex.uprobe(symbol, prog, opts, false)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
lnk, err := attachPerfEvent(u, prog)
|
||||
if err != nil {
|
||||
u.Close()
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return lnk, nil
|
||||
}
|
||||
|
||||
// Uretprobe attaches the given eBPF program to a perf event that fires right
|
||||
// before the given symbol exits. For example, /bin/bash::main():
|
||||
//
|
||||
// ex, _ = OpenExecutable("/bin/bash")
|
||||
// ex.Uretprobe("main", prog, nil)
|
||||
//
|
||||
// When using symbols which belongs to shared libraries,
|
||||
// an offset must be provided via options:
|
||||
//
|
||||
// up, err := ex.Uretprobe("main", prog, &UprobeOptions{Offset: 0x123})
|
||||
//
|
||||
// Note: Setting the Offset field in the options supersedes the symbol's offset.
|
||||
//
|
||||
// Losing the reference to the resulting Link (up) will close the Uprobe
|
||||
// and prevent further execution of prog. The Link must be Closed during
|
||||
// program shutdown to avoid leaking system resources.
|
||||
//
|
||||
// Functions provided by shared libraries can currently not be traced and
|
||||
// will result in an ErrNotSupported.
|
||||
func (ex *Executable) Uretprobe(symbol string, prog *ebpf.Program, opts *UprobeOptions) (Link, error) {
|
||||
u, err := ex.uprobe(symbol, prog, opts, true)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
lnk, err := attachPerfEvent(u, prog)
|
||||
if err != nil {
|
||||
u.Close()
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return lnk, nil
|
||||
}
|
||||
|
||||
// uprobe opens a perf event for the given binary/symbol and attaches prog to it.
|
||||
// If ret is true, create a uretprobe.
|
||||
func (ex *Executable) uprobe(symbol string, prog *ebpf.Program, opts *UprobeOptions, ret bool) (*perfEvent, error) {
|
||||
if prog == nil {
|
||||
return nil, fmt.Errorf("prog cannot be nil: %w", errInvalidInput)
|
||||
}
|
||||
if prog.Type() != ebpf.Kprobe {
|
||||
return nil, fmt.Errorf("eBPF program type %s is not Kprobe: %w", prog.Type(), errInvalidInput)
|
||||
}
|
||||
if opts == nil {
|
||||
opts = &UprobeOptions{}
|
||||
}
|
||||
|
||||
offset, err := ex.address(symbol, opts)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
pid := opts.PID
|
||||
if pid == 0 {
|
||||
pid = perfAllThreads
|
||||
}
|
||||
|
||||
if opts.RefCtrOffset != 0 {
|
||||
if err := haveRefCtrOffsetPMU(); err != nil {
|
||||
return nil, fmt.Errorf("uprobe ref_ctr_offset: %w", err)
|
||||
}
|
||||
}
|
||||
|
||||
args := probeArgs{
|
||||
symbol: symbol,
|
||||
path: ex.path,
|
||||
offset: offset,
|
||||
pid: pid,
|
||||
refCtrOffset: opts.RefCtrOffset,
|
||||
ret: ret,
|
||||
cookie: opts.Cookie,
|
||||
}
|
||||
|
||||
// Use uprobe PMU if the kernel has it available.
|
||||
tp, err := pmuUprobe(args)
|
||||
if err == nil {
|
||||
return tp, nil
|
||||
}
|
||||
if err != nil && !errors.Is(err, ErrNotSupported) {
|
||||
return nil, fmt.Errorf("creating perf_uprobe PMU: %w", err)
|
||||
}
|
||||
|
||||
// Use tracefs if uprobe PMU is missing.
|
||||
args.symbol = sanitizeSymbol(symbol)
|
||||
tp, err = tracefsUprobe(args)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("creating trace event '%s:%s' in tracefs: %w", ex.path, symbol, err)
|
||||
}
|
||||
|
||||
return tp, nil
|
||||
}
|
||||
|
||||
// pmuUprobe opens a perf event based on the uprobe PMU.
|
||||
func pmuUprobe(args probeArgs) (*perfEvent, error) {
|
||||
return pmuProbe(uprobeType, args)
|
||||
}
|
||||
|
||||
// tracefsUprobe creates a Uprobe tracefs entry.
|
||||
func tracefsUprobe(args probeArgs) (*perfEvent, error) {
|
||||
return tracefsProbe(uprobeType, args)
|
||||
}
|
||||
|
||||
// sanitizeSymbol replaces every invalid character for the tracefs api with an underscore.
|
||||
// It is equivalent to calling regexp.MustCompile("[^a-zA-Z0-9]+").ReplaceAllString("_").
|
||||
func sanitizeSymbol(s string) string {
|
||||
var b strings.Builder
|
||||
b.Grow(len(s))
|
||||
var skip bool
|
||||
for _, c := range []byte(s) {
|
||||
switch {
|
||||
case c >= 'a' && c <= 'z',
|
||||
c >= 'A' && c <= 'Z',
|
||||
c >= '0' && c <= '9':
|
||||
skip = false
|
||||
b.WriteByte(c)
|
||||
|
||||
default:
|
||||
if !skip {
|
||||
b.WriteByte('_')
|
||||
skip = true
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return b.String()
|
||||
}
|
||||
|
||||
// uprobeToken creates the PATH:OFFSET(REF_CTR_OFFSET) token for the tracefs api.
|
||||
func uprobeToken(args probeArgs) string {
|
||||
po := fmt.Sprintf("%s:%#x", args.path, args.offset)
|
||||
|
||||
if args.refCtrOffset != 0 {
|
||||
// This is not documented in Documentation/trace/uprobetracer.txt.
|
||||
// elixir.bootlin.com/linux/v5.15-rc7/source/kernel/trace/trace.c#L5564
|
||||
po += fmt.Sprintf("(%#x)", args.refCtrOffset)
|
||||
}
|
||||
|
||||
return po
|
||||
}
|
||||
|
||||
func uretprobeBit() (uint64, error) {
|
||||
uprobeRetprobeBit.once.Do(func() {
|
||||
uprobeRetprobeBit.value, uprobeRetprobeBit.err = determineRetprobeBit(uprobeType)
|
||||
})
|
||||
return uprobeRetprobeBit.value, uprobeRetprobeBit.err
|
||||
}
|
|
@ -0,0 +1,54 @@
|
|||
package link
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
|
||||
"github.com/cilium/ebpf"
|
||||
)
|
||||
|
||||
// XDPAttachFlags represents how XDP program will be attached to interface.
|
||||
type XDPAttachFlags uint32
|
||||
|
||||
const (
|
||||
// XDPGenericMode (SKB) links XDP BPF program for drivers which do
|
||||
// not yet support native XDP.
|
||||
XDPGenericMode XDPAttachFlags = 1 << (iota + 1)
|
||||
// XDPDriverMode links XDP BPF program into the driver’s receive path.
|
||||
XDPDriverMode
|
||||
// XDPOffloadMode offloads the entire XDP BPF program into hardware.
|
||||
XDPOffloadMode
|
||||
)
|
||||
|
||||
type XDPOptions struct {
|
||||
// Program must be an XDP BPF program.
|
||||
Program *ebpf.Program
|
||||
|
||||
// Interface is the interface index to attach program to.
|
||||
Interface int
|
||||
|
||||
// Flags is one of XDPAttachFlags (optional).
|
||||
//
|
||||
// Only one XDP mode should be set, without flag defaults
|
||||
// to driver/generic mode (best effort).
|
||||
Flags XDPAttachFlags
|
||||
}
|
||||
|
||||
// AttachXDP links an XDP BPF program to an XDP hook.
|
||||
func AttachXDP(opts XDPOptions) (Link, error) {
|
||||
if t := opts.Program.Type(); t != ebpf.XDP {
|
||||
return nil, fmt.Errorf("invalid program type %s, expected XDP", t)
|
||||
}
|
||||
|
||||
if opts.Interface < 1 {
|
||||
return nil, fmt.Errorf("invalid interface index: %d", opts.Interface)
|
||||
}
|
||||
|
||||
rawLink, err := AttachRawLink(RawLinkOptions{
|
||||
Program: opts.Program,
|
||||
Attach: ebpf.AttachXDP,
|
||||
Target: opts.Interface,
|
||||
Flags: uint32(opts.Flags),
|
||||
})
|
||||
|
||||
return rawLink, err
|
||||
}
|
|
@ -1,133 +1,238 @@
|
|||
package ebpf
|
||||
|
||||
import (
|
||||
"errors"
|
||||
"fmt"
|
||||
"sync"
|
||||
|
||||
"github.com/cilium/ebpf/asm"
|
||||
"github.com/cilium/ebpf/internal/btf"
|
||||
"github.com/cilium/ebpf/btf"
|
||||
)
|
||||
|
||||
// link resolves bpf-to-bpf calls.
|
||||
// splitSymbols splits insns into subsections delimited by Symbol Instructions.
|
||||
// insns cannot be empty and must start with a Symbol Instruction.
|
||||
//
|
||||
// Each library may contain multiple functions / labels, and is only linked
|
||||
// if prog references one of these functions.
|
||||
//
|
||||
// Libraries also linked.
|
||||
func link(prog *ProgramSpec, libs []*ProgramSpec) error {
|
||||
var (
|
||||
linked = make(map[*ProgramSpec]bool)
|
||||
pending = []asm.Instructions{prog.Instructions}
|
||||
insns asm.Instructions
|
||||
)
|
||||
for len(pending) > 0 {
|
||||
insns, pending = pending[0], pending[1:]
|
||||
for _, lib := range libs {
|
||||
if linked[lib] {
|
||||
continue
|
||||
// The resulting map is indexed by Symbol name.
|
||||
func splitSymbols(insns asm.Instructions) (map[string]asm.Instructions, error) {
|
||||
if len(insns) == 0 {
|
||||
return nil, errors.New("insns is empty")
|
||||
}
|
||||
|
||||
needed, err := needSection(insns, lib.Instructions)
|
||||
if insns[0].Symbol() == "" {
|
||||
return nil, errors.New("insns must start with a Symbol")
|
||||
}
|
||||
|
||||
var name string
|
||||
progs := make(map[string]asm.Instructions)
|
||||
for _, ins := range insns {
|
||||
if sym := ins.Symbol(); sym != "" {
|
||||
if progs[sym] != nil {
|
||||
return nil, fmt.Errorf("insns contains duplicate Symbol %s", sym)
|
||||
}
|
||||
name = sym
|
||||
}
|
||||
|
||||
progs[name] = append(progs[name], ins)
|
||||
}
|
||||
|
||||
return progs, nil
|
||||
}
|
||||
|
||||
// The linker is responsible for resolving bpf-to-bpf calls between programs
|
||||
// within an ELF. Each BPF program must be a self-contained binary blob,
|
||||
// so when an instruction in one ELF program section wants to jump to
|
||||
// a function in another, the linker needs to pull in the bytecode
|
||||
// (and BTF info) of the target function and concatenate the instruction
|
||||
// streams.
|
||||
//
|
||||
// Later on in the pipeline, all call sites are fixed up with relative jumps
|
||||
// within this newly-created instruction stream to then finally hand off to
|
||||
// the kernel with BPF_PROG_LOAD.
|
||||
//
|
||||
// Each function is denoted by an ELF symbol and the compiler takes care of
|
||||
// register setup before each jump instruction.
|
||||
|
||||
// hasFunctionReferences returns true if insns contains one or more bpf2bpf
|
||||
// function references.
|
||||
func hasFunctionReferences(insns asm.Instructions) bool {
|
||||
for _, i := range insns {
|
||||
if i.IsFunctionReference() {
|
||||
return true
|
||||
}
|
||||
}
|
||||
return false
|
||||
}
|
||||
|
||||
// applyRelocations collects and applies any CO-RE relocations in insns.
|
||||
//
|
||||
// Passing a nil target will relocate against the running kernel. insns are
|
||||
// modified in place.
|
||||
func applyRelocations(insns asm.Instructions, local, target *btf.Spec) error {
|
||||
var relos []*btf.CORERelocation
|
||||
var reloInsns []*asm.Instruction
|
||||
iter := insns.Iterate()
|
||||
for iter.Next() {
|
||||
if relo := btf.CORERelocationMetadata(iter.Ins); relo != nil {
|
||||
relos = append(relos, relo)
|
||||
reloInsns = append(reloInsns, iter.Ins)
|
||||
}
|
||||
}
|
||||
|
||||
if len(relos) == 0 {
|
||||
return nil
|
||||
}
|
||||
|
||||
target, err := maybeLoadKernelBTF(target)
|
||||
if err != nil {
|
||||
return fmt.Errorf("linking %s: %w", lib.Name, err)
|
||||
return err
|
||||
}
|
||||
|
||||
if !needed {
|
||||
continue
|
||||
fixups, err := btf.CORERelocate(local, target, relos)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
linked[lib] = true
|
||||
prog.Instructions = append(prog.Instructions, lib.Instructions...)
|
||||
pending = append(pending, lib.Instructions)
|
||||
|
||||
if prog.BTF != nil && lib.BTF != nil {
|
||||
if err := btf.ProgramAppend(prog.BTF, lib.BTF); err != nil {
|
||||
return fmt.Errorf("linking BTF of %s: %w", lib.Name, err)
|
||||
}
|
||||
}
|
||||
for i, fixup := range fixups {
|
||||
if err := fixup.Apply(reloInsns[i]); err != nil {
|
||||
return fmt.Errorf("apply fixup %s: %w", &fixup, err)
|
||||
}
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
func needSection(insns, section asm.Instructions) (bool, error) {
|
||||
// A map of symbols to the libraries which contain them.
|
||||
symbols, err := section.SymbolOffsets()
|
||||
if err != nil {
|
||||
return false, err
|
||||
// flattenPrograms resolves bpf-to-bpf calls for a set of programs.
|
||||
//
|
||||
// Links all programs in names by modifying their ProgramSpec in progs.
|
||||
func flattenPrograms(progs map[string]*ProgramSpec, names []string) {
|
||||
// Pre-calculate all function references.
|
||||
refs := make(map[*ProgramSpec][]string)
|
||||
for _, prog := range progs {
|
||||
refs[prog] = prog.Instructions.FunctionReferences()
|
||||
}
|
||||
|
||||
for _, ins := range insns {
|
||||
if ins.Reference == "" {
|
||||
// Create a flattened instruction stream, but don't modify progs yet to
|
||||
// avoid linking multiple times.
|
||||
flattened := make([]asm.Instructions, 0, len(names))
|
||||
for _, name := range names {
|
||||
flattened = append(flattened, flattenInstructions(name, progs, refs))
|
||||
}
|
||||
|
||||
// Finally, assign the flattened instructions.
|
||||
for i, name := range names {
|
||||
progs[name].Instructions = flattened[i]
|
||||
}
|
||||
}
|
||||
|
||||
// flattenInstructions resolves bpf-to-bpf calls for a single program.
|
||||
//
|
||||
// Flattens the instructions of prog by concatenating the instructions of all
|
||||
// direct and indirect dependencies.
|
||||
//
|
||||
// progs contains all referenceable programs, while refs contain the direct
|
||||
// dependencies of each program.
|
||||
func flattenInstructions(name string, progs map[string]*ProgramSpec, refs map[*ProgramSpec][]string) asm.Instructions {
|
||||
prog := progs[name]
|
||||
|
||||
insns := make(asm.Instructions, len(prog.Instructions))
|
||||
copy(insns, prog.Instructions)
|
||||
|
||||
// Add all direct references of prog to the list of to be linked programs.
|
||||
pending := make([]string, len(refs[prog]))
|
||||
copy(pending, refs[prog])
|
||||
|
||||
// All references for which we've appended instructions.
|
||||
linked := make(map[string]bool)
|
||||
|
||||
// Iterate all pending references. We can't use a range since pending is
|
||||
// modified in the body below.
|
||||
for len(pending) > 0 {
|
||||
var ref string
|
||||
ref, pending = pending[0], pending[1:]
|
||||
|
||||
if linked[ref] {
|
||||
// We've already linked this ref, don't append instructions again.
|
||||
continue
|
||||
}
|
||||
|
||||
if ins.OpCode.JumpOp() != asm.Call || ins.Src != asm.PseudoCall {
|
||||
progRef := progs[ref]
|
||||
if progRef == nil {
|
||||
// We don't have instructions that go with this reference. This
|
||||
// happens when calling extern functions.
|
||||
continue
|
||||
}
|
||||
|
||||
if ins.Constant != -1 {
|
||||
// This is already a valid call, no need to link again.
|
||||
continue
|
||||
insns = append(insns, progRef.Instructions...)
|
||||
linked[ref] = true
|
||||
|
||||
// Make sure we link indirect references.
|
||||
pending = append(pending, refs[progRef]...)
|
||||
}
|
||||
|
||||
if _, ok := symbols[ins.Reference]; !ok {
|
||||
// Symbol isn't available in this section
|
||||
continue
|
||||
return insns
|
||||
}
|
||||
|
||||
// At this point we know that at least one function in the
|
||||
// library is called from insns, so we have to link it.
|
||||
return true, nil
|
||||
}
|
||||
|
||||
// None of the functions in the section are called.
|
||||
return false, nil
|
||||
}
|
||||
|
||||
func fixupJumpsAndCalls(insns asm.Instructions) error {
|
||||
symbolOffsets := make(map[string]asm.RawInstructionOffset)
|
||||
// fixupAndValidate is called by the ELF reader right before marshaling the
|
||||
// instruction stream. It performs last-minute adjustments to the program and
|
||||
// runs some sanity checks before sending it off to the kernel.
|
||||
func fixupAndValidate(insns asm.Instructions) error {
|
||||
iter := insns.Iterate()
|
||||
for iter.Next() {
|
||||
ins := iter.Ins
|
||||
|
||||
if ins.Symbol == "" {
|
||||
continue
|
||||
// Map load was tagged with a Reference, but does not contain a Map pointer.
|
||||
if ins.IsLoadFromMap() && ins.Reference() != "" && ins.Map() == nil {
|
||||
return fmt.Errorf("instruction %d: map %s: %w", iter.Index, ins.Reference(), asm.ErrUnsatisfiedMapReference)
|
||||
}
|
||||
|
||||
if _, ok := symbolOffsets[ins.Symbol]; ok {
|
||||
return fmt.Errorf("duplicate symbol %s", ins.Symbol)
|
||||
}
|
||||
|
||||
symbolOffsets[ins.Symbol] = iter.Offset
|
||||
}
|
||||
|
||||
iter = insns.Iterate()
|
||||
for iter.Next() {
|
||||
i := iter.Index
|
||||
offset := iter.Offset
|
||||
ins := iter.Ins
|
||||
|
||||
switch {
|
||||
case ins.IsFunctionCall() && ins.Constant == -1:
|
||||
// Rewrite bpf to bpf call
|
||||
callOffset, ok := symbolOffsets[ins.Reference]
|
||||
if !ok {
|
||||
return fmt.Errorf("instruction %d: reference to missing symbol %q", i, ins.Reference)
|
||||
}
|
||||
|
||||
ins.Constant = int64(callOffset - offset - 1)
|
||||
|
||||
case ins.OpCode.Class() == asm.JumpClass && ins.Offset == -1:
|
||||
// Rewrite jump to label
|
||||
jumpOffset, ok := symbolOffsets[ins.Reference]
|
||||
if !ok {
|
||||
return fmt.Errorf("instruction %d: reference to missing symbol %q", i, ins.Reference)
|
||||
}
|
||||
|
||||
ins.Offset = int16(jumpOffset - offset - 1)
|
||||
}
|
||||
fixupProbeReadKernel(ins)
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// fixupProbeReadKernel replaces calls to bpf_probe_read_{kernel,user}(_str)
|
||||
// with bpf_probe_read(_str) on kernels that don't support it yet.
|
||||
func fixupProbeReadKernel(ins *asm.Instruction) {
|
||||
if !ins.IsBuiltinCall() {
|
||||
return
|
||||
}
|
||||
|
||||
// Kernel supports bpf_probe_read_kernel, nothing to do.
|
||||
if haveProbeReadKernel() == nil {
|
||||
return
|
||||
}
|
||||
|
||||
switch asm.BuiltinFunc(ins.Constant) {
|
||||
case asm.FnProbeReadKernel, asm.FnProbeReadUser:
|
||||
ins.Constant = int64(asm.FnProbeRead)
|
||||
case asm.FnProbeReadKernelStr, asm.FnProbeReadUserStr:
|
||||
ins.Constant = int64(asm.FnProbeReadStr)
|
||||
}
|
||||
}
|
||||
|
||||
var kernelBTF struct {
|
||||
sync.Mutex
|
||||
spec *btf.Spec
|
||||
}
|
||||
|
||||
// maybeLoadKernelBTF loads the current kernel's BTF if spec is nil, otherwise
|
||||
// it returns spec unchanged.
|
||||
//
|
||||
// The kernel BTF is cached for the lifetime of the process.
|
||||
func maybeLoadKernelBTF(spec *btf.Spec) (*btf.Spec, error) {
|
||||
if spec != nil {
|
||||
return spec, nil
|
||||
}
|
||||
|
||||
kernelBTF.Lock()
|
||||
defer kernelBTF.Unlock()
|
||||
|
||||
if kernelBTF.spec != nil {
|
||||
return kernelBTF.spec, nil
|
||||
}
|
||||
|
||||
var err error
|
||||
kernelBTF.spec, err = btf.LoadKernelSpec()
|
||||
return kernelBTF.spec, err
|
||||
}
|
||||
|
|
File diff suppressed because it is too large
Load Diff
|
@ -8,9 +8,11 @@ import (
|
|||
"fmt"
|
||||
"reflect"
|
||||
"runtime"
|
||||
"sync"
|
||||
"unsafe"
|
||||
|
||||
"github.com/cilium/ebpf/internal"
|
||||
"github.com/cilium/ebpf/internal/sys"
|
||||
)
|
||||
|
||||
// marshalPtr converts an arbitrary value into a pointer suitable
|
||||
|
@ -18,17 +20,17 @@ import (
|
|||
//
|
||||
// As an optimization, it returns the original value if it is an
|
||||
// unsafe.Pointer.
|
||||
func marshalPtr(data interface{}, length int) (internal.Pointer, error) {
|
||||
func marshalPtr(data interface{}, length int) (sys.Pointer, error) {
|
||||
if ptr, ok := data.(unsafe.Pointer); ok {
|
||||
return internal.NewPointer(ptr), nil
|
||||
return sys.NewPointer(ptr), nil
|
||||
}
|
||||
|
||||
buf, err := marshalBytes(data, length)
|
||||
if err != nil {
|
||||
return internal.Pointer{}, err
|
||||
return sys.Pointer{}, err
|
||||
}
|
||||
|
||||
return internal.NewSlicePointer(buf), nil
|
||||
return sys.NewSlicePointer(buf), nil
|
||||
}
|
||||
|
||||
// marshalBytes converts an arbitrary value into a byte buffer.
|
||||
|
@ -39,6 +41,10 @@ func marshalPtr(data interface{}, length int) (internal.Pointer, error) {
|
|||
// Returns an error if the given value isn't representable in exactly
|
||||
// length bytes.
|
||||
func marshalBytes(data interface{}, length int) (buf []byte, err error) {
|
||||
if data == nil {
|
||||
return nil, errors.New("can't marshal a nil value")
|
||||
}
|
||||
|
||||
switch value := data.(type) {
|
||||
case encoding.BinaryMarshaler:
|
||||
buf, err = value.MarshalBinary()
|
||||
|
@ -68,29 +74,32 @@ func marshalBytes(data interface{}, length int) (buf []byte, err error) {
|
|||
return buf, nil
|
||||
}
|
||||
|
||||
func makeBuffer(dst interface{}, length int) (internal.Pointer, []byte) {
|
||||
func makeBuffer(dst interface{}, length int) (sys.Pointer, []byte) {
|
||||
if ptr, ok := dst.(unsafe.Pointer); ok {
|
||||
return internal.NewPointer(ptr), nil
|
||||
return sys.NewPointer(ptr), nil
|
||||
}
|
||||
|
||||
buf := make([]byte, length)
|
||||
return internal.NewSlicePointer(buf), buf
|
||||
return sys.NewSlicePointer(buf), buf
|
||||
}
|
||||
|
||||
var bytesReaderPool = sync.Pool{
|
||||
New: func() interface{} {
|
||||
return new(bytes.Reader)
|
||||
},
|
||||
}
|
||||
|
||||
// unmarshalBytes converts a byte buffer into an arbitrary value.
|
||||
//
|
||||
// Prefer using Map.unmarshalKey and Map.unmarshalValue if possible, since
|
||||
// those have special cases that allow more types to be encoded.
|
||||
//
|
||||
// The common int32 and int64 types are directly handled to avoid
|
||||
// unnecessary heap allocations as happening in the default case.
|
||||
func unmarshalBytes(data interface{}, buf []byte) error {
|
||||
switch value := data.(type) {
|
||||
case unsafe.Pointer:
|
||||
sh := &reflect.SliceHeader{
|
||||
Data: uintptr(value),
|
||||
Len: len(buf),
|
||||
Cap: len(buf),
|
||||
}
|
||||
|
||||
dst := *(*[]byte)(unsafe.Pointer(sh))
|
||||
dst := unsafe.Slice((*byte)(value), len(buf))
|
||||
copy(dst, buf)
|
||||
runtime.KeepAlive(value)
|
||||
return nil
|
||||
|
@ -104,12 +113,38 @@ func unmarshalBytes(data interface{}, buf []byte) error {
|
|||
case *[]byte:
|
||||
*value = buf
|
||||
return nil
|
||||
case *int32:
|
||||
if len(buf) < 4 {
|
||||
return errors.New("int32 requires 4 bytes")
|
||||
}
|
||||
*value = int32(internal.NativeEndian.Uint32(buf))
|
||||
return nil
|
||||
case *uint32:
|
||||
if len(buf) < 4 {
|
||||
return errors.New("uint32 requires 4 bytes")
|
||||
}
|
||||
*value = internal.NativeEndian.Uint32(buf)
|
||||
return nil
|
||||
case *int64:
|
||||
if len(buf) < 8 {
|
||||
return errors.New("int64 requires 8 bytes")
|
||||
}
|
||||
*value = int64(internal.NativeEndian.Uint64(buf))
|
||||
return nil
|
||||
case *uint64:
|
||||
if len(buf) < 8 {
|
||||
return errors.New("uint64 requires 8 bytes")
|
||||
}
|
||||
*value = internal.NativeEndian.Uint64(buf)
|
||||
return nil
|
||||
case string:
|
||||
return errors.New("require pointer to string")
|
||||
case []byte:
|
||||
return errors.New("require pointer to []byte")
|
||||
default:
|
||||
rd := bytes.NewReader(buf)
|
||||
rd := bytesReaderPool.Get().(*bytes.Reader)
|
||||
rd.Reset(buf)
|
||||
defer bytesReaderPool.Put(rd)
|
||||
if err := binary.Read(rd, internal.NativeEndian, value); err != nil {
|
||||
return fmt.Errorf("decoding %T: %v", value, err)
|
||||
}
|
||||
|
@ -123,38 +158,38 @@ func unmarshalBytes(data interface{}, buf []byte) error {
|
|||
// Values are initialized to zero if the slice has less elements than CPUs.
|
||||
//
|
||||
// slice must have a type like []elementType.
|
||||
func marshalPerCPUValue(slice interface{}, elemLength int) (internal.Pointer, error) {
|
||||
func marshalPerCPUValue(slice interface{}, elemLength int) (sys.Pointer, error) {
|
||||
sliceType := reflect.TypeOf(slice)
|
||||
if sliceType.Kind() != reflect.Slice {
|
||||
return internal.Pointer{}, errors.New("per-CPU value requires slice")
|
||||
return sys.Pointer{}, errors.New("per-CPU value requires slice")
|
||||
}
|
||||
|
||||
possibleCPUs, err := internal.PossibleCPUs()
|
||||
if err != nil {
|
||||
return internal.Pointer{}, err
|
||||
return sys.Pointer{}, err
|
||||
}
|
||||
|
||||
sliceValue := reflect.ValueOf(slice)
|
||||
sliceLen := sliceValue.Len()
|
||||
if sliceLen > possibleCPUs {
|
||||
return internal.Pointer{}, fmt.Errorf("per-CPU value exceeds number of CPUs")
|
||||
return sys.Pointer{}, fmt.Errorf("per-CPU value exceeds number of CPUs")
|
||||
}
|
||||
|
||||
alignedElemLength := align(elemLength, 8)
|
||||
alignedElemLength := internal.Align(elemLength, 8)
|
||||
buf := make([]byte, alignedElemLength*possibleCPUs)
|
||||
|
||||
for i := 0; i < sliceLen; i++ {
|
||||
elem := sliceValue.Index(i).Interface()
|
||||
elemBytes, err := marshalBytes(elem, elemLength)
|
||||
if err != nil {
|
||||
return internal.Pointer{}, err
|
||||
return sys.Pointer{}, err
|
||||
}
|
||||
|
||||
offset := i * alignedElemLength
|
||||
copy(buf[offset:offset+elemLength], elemBytes)
|
||||
}
|
||||
|
||||
return internal.NewSlicePointer(buf), nil
|
||||
return sys.NewSlicePointer(buf), nil
|
||||
}
|
||||
|
||||
// unmarshalPerCPUValue decodes a buffer into a slice containing one value per
|
||||
|
@ -210,7 +245,3 @@ func unmarshalPerCPUValue(slicePtr interface{}, elemLength int, buf []byte) erro
|
|||
reflect.ValueOf(slicePtr).Elem().Set(slice)
|
||||
return nil
|
||||
}
|
||||
|
||||
func align(n, alignment int) int {
|
||||
return (int(n) + alignment - 1) / alignment * alignment
|
||||
}
|
||||
|
|
|
@ -1,42 +0,0 @@
|
|||
package ebpf
|
||||
|
||||
import (
|
||||
"errors"
|
||||
"fmt"
|
||||
"os"
|
||||
|
||||
"github.com/cilium/ebpf/internal"
|
||||
)
|
||||
|
||||
func pin(currentPath, newPath string, fd *internal.FD) error {
|
||||
if newPath == "" {
|
||||
return errors.New("given pinning path cannot be empty")
|
||||
}
|
||||
if currentPath == "" {
|
||||
return internal.BPFObjPin(newPath, fd)
|
||||
}
|
||||
if currentPath == newPath {
|
||||
return nil
|
||||
}
|
||||
var err error
|
||||
// Object is now moved to the new pinning path.
|
||||
if err = os.Rename(currentPath, newPath); err == nil {
|
||||
return nil
|
||||
}
|
||||
if !os.IsNotExist(err) {
|
||||
return fmt.Errorf("unable to move pinned object to new path %v: %w", newPath, err)
|
||||
}
|
||||
// Internal state not in sync with the file system so let's fix it.
|
||||
return internal.BPFObjPin(newPath, fd)
|
||||
}
|
||||
|
||||
func unpin(pinnedPath string) error {
|
||||
if pinnedPath == "" {
|
||||
return nil
|
||||
}
|
||||
err := os.Remove(pinnedPath)
|
||||
if err == nil || os.IsNotExist(err) {
|
||||
return nil
|
||||
}
|
||||
return err
|
||||
}
|
|
@ -7,12 +7,14 @@ import (
|
|||
"fmt"
|
||||
"math"
|
||||
"path/filepath"
|
||||
"runtime"
|
||||
"strings"
|
||||
"time"
|
||||
|
||||
"github.com/cilium/ebpf/asm"
|
||||
"github.com/cilium/ebpf/btf"
|
||||
"github.com/cilium/ebpf/internal"
|
||||
"github.com/cilium/ebpf/internal/btf"
|
||||
"github.com/cilium/ebpf/internal/sys"
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
|
@ -41,6 +43,13 @@ type ProgramOptions struct {
|
|||
// Controls the output buffer size for the verifier. Defaults to
|
||||
// DefaultVerifierLogSize.
|
||||
LogSize int
|
||||
// Type information used for CO-RE relocations and when attaching to
|
||||
// kernel functions.
|
||||
//
|
||||
// This is useful in environments where the kernel BTF is not available
|
||||
// (containers) or where it is in a non-standard location. Defaults to
|
||||
// use the kernel BTF from a well-known location if nil.
|
||||
KernelTypes *btf.Spec
|
||||
}
|
||||
|
||||
// ProgramSpec defines a Program.
|
||||
|
@ -48,29 +57,48 @@ type ProgramSpec struct {
|
|||
// Name is passed to the kernel as a debug aid. Must only contain
|
||||
// alpha numeric and '_' characters.
|
||||
Name string
|
||||
|
||||
// Type determines at which hook in the kernel a program will run.
|
||||
Type ProgramType
|
||||
|
||||
// AttachType of the program, needed to differentiate allowed context
|
||||
// accesses in some newer program types like CGroupSockAddr.
|
||||
//
|
||||
// Available on kernels 4.17 and later.
|
||||
AttachType AttachType
|
||||
// Name of a kernel data structure to attach to. It's interpretation
|
||||
// depends on Type and AttachType.
|
||||
|
||||
// Name of a kernel data structure or function to attach to. Its
|
||||
// interpretation depends on Type and AttachType.
|
||||
AttachTo string
|
||||
|
||||
// The program to attach to. Must be provided manually.
|
||||
AttachTarget *Program
|
||||
|
||||
// The name of the ELF section this program orininated from.
|
||||
SectionName string
|
||||
|
||||
Instructions asm.Instructions
|
||||
|
||||
// Flags is passed to the kernel and specifies additional program
|
||||
// load attributes.
|
||||
Flags uint32
|
||||
|
||||
// License of the program. Some helpers are only available if
|
||||
// the license is deemed compatible with the GPL.
|
||||
//
|
||||
// See https://www.kernel.org/doc/html/latest/process/license-rules.html#id1
|
||||
License string
|
||||
|
||||
// Version used by tracing programs.
|
||||
// Version used by Kprobe programs.
|
||||
//
|
||||
// Deprecated: superseded by BTF.
|
||||
// Deprecated on kernels 5.0 and later. Leave empty to let the library
|
||||
// detect this value automatically.
|
||||
KernelVersion uint32
|
||||
|
||||
// The BTF associated with this program. Changing Instructions
|
||||
// will most likely invalidate the contained data, and may
|
||||
// result in errors when attempting to load it into the kernel.
|
||||
BTF *btf.Program
|
||||
BTF *btf.Spec
|
||||
|
||||
// The byte order this program was compiled for, may be nil.
|
||||
ByteOrder binary.ByteOrder
|
||||
|
@ -95,6 +123,8 @@ func (ps *ProgramSpec) Tag() (string, error) {
|
|||
return ps.Instructions.Tag(internal.NativeEndian)
|
||||
}
|
||||
|
||||
type VerifierError = internal.VerifierError
|
||||
|
||||
// Program represents BPF program loaded into the kernel.
|
||||
//
|
||||
// It is not safe to close a Program which is used by other goroutines.
|
||||
|
@ -103,7 +133,7 @@ type Program struct {
|
|||
// otherwise it is empty.
|
||||
VerifierLog string
|
||||
|
||||
fd *internal.FD
|
||||
fd *sys.FD
|
||||
name string
|
||||
pinnedPath string
|
||||
typ ProgramType
|
||||
|
@ -111,8 +141,7 @@ type Program struct {
|
|||
|
||||
// NewProgram creates a new Program.
|
||||
//
|
||||
// Loading a program for the first time will perform
|
||||
// feature detection by loading small, temporary programs.
|
||||
// See NewProgramWithOptions for details.
|
||||
func NewProgram(spec *ProgramSpec) (*Program, error) {
|
||||
return NewProgramWithOptions(spec, ProgramOptions{})
|
||||
}
|
||||
|
@ -121,99 +150,131 @@ func NewProgram(spec *ProgramSpec) (*Program, error) {
|
|||
//
|
||||
// Loading a program for the first time will perform
|
||||
// feature detection by loading small, temporary programs.
|
||||
//
|
||||
// Returns an error wrapping VerifierError if the program or its BTF is rejected
|
||||
// by the kernel.
|
||||
func NewProgramWithOptions(spec *ProgramSpec, opts ProgramOptions) (*Program, error) {
|
||||
btfs := make(btfHandleCache)
|
||||
defer btfs.close()
|
||||
|
||||
return newProgramWithOptions(spec, opts, btfs)
|
||||
if spec == nil {
|
||||
return nil, errors.New("can't load a program from a nil spec")
|
||||
}
|
||||
|
||||
func newProgramWithOptions(spec *ProgramSpec, opts ProgramOptions, btfs btfHandleCache) (*Program, error) {
|
||||
handles := newHandleCache()
|
||||
defer handles.close()
|
||||
|
||||
prog, err := newProgramWithOptions(spec, opts, handles)
|
||||
if errors.Is(err, asm.ErrUnsatisfiedMapReference) {
|
||||
return nil, fmt.Errorf("cannot load program without loading its whole collection: %w", err)
|
||||
}
|
||||
return prog, err
|
||||
}
|
||||
|
||||
func newProgramWithOptions(spec *ProgramSpec, opts ProgramOptions, handles *handleCache) (*Program, error) {
|
||||
if len(spec.Instructions) == 0 {
|
||||
return nil, errors.New("Instructions cannot be empty")
|
||||
return nil, errors.New("instructions cannot be empty")
|
||||
}
|
||||
|
||||
if len(spec.License) == 0 {
|
||||
return nil, errors.New("License cannot be empty")
|
||||
if spec.Type == UnspecifiedProgram {
|
||||
return nil, errors.New("can't load program of unspecified type")
|
||||
}
|
||||
|
||||
if spec.ByteOrder != nil && spec.ByteOrder != internal.NativeEndian {
|
||||
return nil, fmt.Errorf("can't load %s program on %s", spec.ByteOrder, internal.NativeEndian)
|
||||
}
|
||||
|
||||
insns := make(asm.Instructions, len(spec.Instructions))
|
||||
copy(insns, spec.Instructions)
|
||||
|
||||
if err := fixupJumpsAndCalls(insns); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
buf := bytes.NewBuffer(make([]byte, 0, len(spec.Instructions)*asm.InstructionSize))
|
||||
err := insns.Marshal(buf, internal.NativeEndian)
|
||||
// Kernels before 5.0 (6c4fc209fcf9 "bpf: remove useless version check for prog load")
|
||||
// require the version field to be set to the value of the KERNEL_VERSION
|
||||
// macro for kprobe-type programs.
|
||||
// Overwrite Kprobe program version if set to zero or the magic version constant.
|
||||
kv := spec.KernelVersion
|
||||
if spec.Type == Kprobe && (kv == 0 || kv == internal.MagicKernelVersion) {
|
||||
v, err := internal.KernelVersion()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
return nil, fmt.Errorf("detecting kernel version: %w", err)
|
||||
}
|
||||
kv = v.Kernel()
|
||||
}
|
||||
|
||||
bytecode := buf.Bytes()
|
||||
insCount := uint32(len(bytecode) / asm.InstructionSize)
|
||||
attr := &bpfProgLoadAttr{
|
||||
progType: spec.Type,
|
||||
expectedAttachType: spec.AttachType,
|
||||
insCount: insCount,
|
||||
instructions: internal.NewSlicePointer(bytecode),
|
||||
license: internal.NewStringPointer(spec.License),
|
||||
kernelVersion: spec.KernelVersion,
|
||||
attr := &sys.ProgLoadAttr{
|
||||
ProgType: sys.ProgType(spec.Type),
|
||||
ProgFlags: spec.Flags,
|
||||
ExpectedAttachType: sys.AttachType(spec.AttachType),
|
||||
License: sys.NewStringPointer(spec.License),
|
||||
KernVersion: kv,
|
||||
}
|
||||
|
||||
if haveObjName() == nil {
|
||||
attr.progName = newBPFObjName(spec.Name)
|
||||
attr.ProgName = sys.NewObjName(spec.Name)
|
||||
}
|
||||
|
||||
kernelTypes := opts.KernelTypes
|
||||
|
||||
insns := make(asm.Instructions, len(spec.Instructions))
|
||||
copy(insns, spec.Instructions)
|
||||
|
||||
var btfDisabled bool
|
||||
if spec.BTF != nil {
|
||||
if relos, err := btf.ProgramRelocations(spec.BTF, nil); err != nil {
|
||||
return nil, fmt.Errorf("CO-RE relocations: %s", err)
|
||||
} else if len(relos) > 0 {
|
||||
return nil, fmt.Errorf("applying CO-RE relocations: %w", ErrNotSupported)
|
||||
if err := applyRelocations(insns, spec.BTF, kernelTypes); err != nil {
|
||||
return nil, fmt.Errorf("apply CO-RE relocations: %w", err)
|
||||
}
|
||||
|
||||
handle, err := btfs.load(btf.ProgramSpec(spec.BTF))
|
||||
handle, err := handles.btfHandle(spec.BTF)
|
||||
btfDisabled = errors.Is(err, btf.ErrNotSupported)
|
||||
if err != nil && !btfDisabled {
|
||||
return nil, fmt.Errorf("load BTF: %w", err)
|
||||
}
|
||||
|
||||
if handle != nil {
|
||||
attr.progBTFFd = uint32(handle.FD())
|
||||
attr.ProgBtfFd = uint32(handle.FD())
|
||||
|
||||
recSize, bytes, err := btf.ProgramLineInfos(spec.BTF)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("get BTF line infos: %w", err)
|
||||
}
|
||||
attr.lineInfoRecSize = recSize
|
||||
attr.lineInfoCnt = uint32(uint64(len(bytes)) / uint64(recSize))
|
||||
attr.lineInfo = internal.NewSlicePointer(bytes)
|
||||
|
||||
recSize, bytes, err = btf.ProgramFuncInfos(spec.BTF)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("get BTF function infos: %w", err)
|
||||
}
|
||||
attr.funcInfoRecSize = recSize
|
||||
attr.funcInfoCnt = uint32(uint64(len(bytes)) / uint64(recSize))
|
||||
attr.funcInfo = internal.NewSlicePointer(bytes)
|
||||
}
|
||||
}
|
||||
|
||||
if spec.AttachTo != "" {
|
||||
target, err := resolveBTFType(spec.AttachTo, spec.Type, spec.AttachType)
|
||||
fib, lib, err := btf.MarshalExtInfos(insns, spec.BTF.TypeID)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if target != nil {
|
||||
attr.attachBTFID = target.ID()
|
||||
|
||||
attr.FuncInfoRecSize = btf.FuncInfoSize
|
||||
attr.FuncInfoCnt = uint32(len(fib)) / btf.FuncInfoSize
|
||||
attr.FuncInfo = sys.NewSlicePointer(fib)
|
||||
|
||||
attr.LineInfoRecSize = btf.LineInfoSize
|
||||
attr.LineInfoCnt = uint32(len(lib)) / btf.LineInfoSize
|
||||
attr.LineInfo = sys.NewSlicePointer(lib)
|
||||
}
|
||||
}
|
||||
|
||||
if err := fixupAndValidate(insns); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
buf := bytes.NewBuffer(make([]byte, 0, insns.Size()))
|
||||
err := insns.Marshal(buf, internal.NativeEndian)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
bytecode := buf.Bytes()
|
||||
attr.Insns = sys.NewSlicePointer(bytecode)
|
||||
attr.InsnCnt = uint32(len(bytecode) / asm.InstructionSize)
|
||||
|
||||
if spec.AttachTarget != nil {
|
||||
targetID, err := findTargetInProgram(spec.AttachTarget, spec.AttachTo, spec.Type, spec.AttachType)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("attach %s/%s: %w", spec.Type, spec.AttachType, err)
|
||||
}
|
||||
|
||||
attr.AttachBtfId = uint32(targetID)
|
||||
attr.AttachProgFd = uint32(spec.AttachTarget.FD())
|
||||
defer runtime.KeepAlive(spec.AttachTarget)
|
||||
} else if spec.AttachTo != "" {
|
||||
targetID, err := findTargetInKernel(kernelTypes, spec.AttachTo, spec.Type, spec.AttachType)
|
||||
if err != nil && !errors.Is(err, errUnrecognizedAttachType) {
|
||||
// We ignore errUnrecognizedAttachType since AttachTo may be non-empty
|
||||
// for programs that don't attach anywhere.
|
||||
return nil, fmt.Errorf("attach %s/%s: %w", spec.Type, spec.AttachType, err)
|
||||
}
|
||||
|
||||
attr.AttachBtfId = uint32(targetID)
|
||||
}
|
||||
|
||||
logSize := DefaultVerifierLogSize
|
||||
if opts.LogSize > 0 {
|
||||
logSize = opts.LogSize
|
||||
|
@ -222,36 +283,46 @@ func newProgramWithOptions(spec *ProgramSpec, opts ProgramOptions, btfs btfHandl
|
|||
var logBuf []byte
|
||||
if opts.LogLevel > 0 {
|
||||
logBuf = make([]byte, logSize)
|
||||
attr.logLevel = opts.LogLevel
|
||||
attr.logSize = uint32(len(logBuf))
|
||||
attr.logBuf = internal.NewSlicePointer(logBuf)
|
||||
attr.LogLevel = opts.LogLevel
|
||||
attr.LogSize = uint32(len(logBuf))
|
||||
attr.LogBuf = sys.NewSlicePointer(logBuf)
|
||||
}
|
||||
|
||||
fd, err := bpfProgLoad(attr)
|
||||
fd, err := sys.ProgLoad(attr)
|
||||
if err == nil {
|
||||
return &Program{internal.CString(logBuf), fd, spec.Name, "", spec.Type}, nil
|
||||
return &Program{unix.ByteSliceToString(logBuf), fd, spec.Name, "", spec.Type}, nil
|
||||
}
|
||||
|
||||
logErr := err
|
||||
if opts.LogLevel == 0 {
|
||||
if opts.LogLevel == 0 && opts.LogSize >= 0 {
|
||||
// Re-run with the verifier enabled to get better error messages.
|
||||
logBuf = make([]byte, logSize)
|
||||
attr.logLevel = 1
|
||||
attr.logSize = uint32(len(logBuf))
|
||||
attr.logBuf = internal.NewSlicePointer(logBuf)
|
||||
|
||||
_, logErr = bpfProgLoad(attr)
|
||||
attr.LogLevel = 1
|
||||
attr.LogSize = uint32(len(logBuf))
|
||||
attr.LogBuf = sys.NewSlicePointer(logBuf)
|
||||
_, _ = sys.ProgLoad(attr)
|
||||
}
|
||||
|
||||
if errors.Is(logErr, unix.EPERM) && logBuf[0] == 0 {
|
||||
switch {
|
||||
case errors.Is(err, unix.EPERM):
|
||||
if len(logBuf) > 0 && logBuf[0] == 0 {
|
||||
// EPERM due to RLIMIT_MEMLOCK happens before the verifier, so we can
|
||||
// check that the log is empty to reduce false positives.
|
||||
return nil, fmt.Errorf("load program: RLIMIT_MEMLOCK may be too low: %w", logErr)
|
||||
return nil, fmt.Errorf("load program: %w (MEMLOCK may be too low, consider rlimit.RemoveMemlock)", err)
|
||||
}
|
||||
|
||||
err = internal.ErrorWithLog(err, logBuf, logErr)
|
||||
fallthrough
|
||||
|
||||
case errors.Is(err, unix.EINVAL):
|
||||
if hasFunctionReferences(spec.Instructions) {
|
||||
if err := haveBPFToBPFCalls(); err != nil {
|
||||
return nil, fmt.Errorf("load program: %w", err)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
err = internal.ErrorWithLog(err, logBuf)
|
||||
if btfDisabled {
|
||||
return nil, fmt.Errorf("load program without BTF: %w", err)
|
||||
return nil, fmt.Errorf("load program: %w (BTF disabled)", err)
|
||||
}
|
||||
return nil, fmt.Errorf("load program: %w", err)
|
||||
}
|
||||
|
@ -262,18 +333,21 @@ func newProgramWithOptions(spec *ProgramSpec, opts ProgramOptions, btfs btfHandl
|
|||
//
|
||||
// Requires at least Linux 4.10.
|
||||
func NewProgramFromFD(fd int) (*Program, error) {
|
||||
if fd < 0 {
|
||||
return nil, errors.New("invalid fd")
|
||||
f, err := sys.NewFD(fd)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return newProgramFromFD(internal.NewFD(uint32(fd)))
|
||||
return newProgramFromFD(f)
|
||||
}
|
||||
|
||||
// NewProgramFromID returns the program for a given id.
|
||||
//
|
||||
// Returns ErrNotExist, if there is no eBPF program with the given id.
|
||||
func NewProgramFromID(id ProgramID) (*Program, error) {
|
||||
fd, err := bpfObjGetFDByID(internal.BPF_PROG_GET_FD_BY_ID, uint32(id))
|
||||
fd, err := sys.ProgGetFdById(&sys.ProgGetFdByIdAttr{
|
||||
Id: uint32(id),
|
||||
})
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("get program by id: %w", err)
|
||||
}
|
||||
|
@ -281,7 +355,7 @@ func NewProgramFromID(id ProgramID) (*Program, error) {
|
|||
return newProgramFromFD(fd)
|
||||
}
|
||||
|
||||
func newProgramFromFD(fd *internal.FD) (*Program, error) {
|
||||
func newProgramFromFD(fd *sys.FD) (*Program, error) {
|
||||
info, err := newProgramInfoFromFd(fd)
|
||||
if err != nil {
|
||||
fd.Close()
|
||||
|
@ -310,18 +384,29 @@ func (p *Program) Info() (*ProgramInfo, error) {
|
|||
return newProgramInfoFromFd(p.fd)
|
||||
}
|
||||
|
||||
// Handle returns a reference to the program's type information in the kernel.
|
||||
//
|
||||
// Returns ErrNotSupported if the kernel has no BTF support, or if there is no
|
||||
// BTF associated with the program.
|
||||
func (p *Program) Handle() (*btf.Handle, error) {
|
||||
info, err := p.Info()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
id, ok := info.BTFID()
|
||||
if !ok {
|
||||
return nil, fmt.Errorf("program %s: retrieve BTF ID: %w", p, ErrNotSupported)
|
||||
}
|
||||
|
||||
return btf.NewHandleFromID(id)
|
||||
}
|
||||
|
||||
// FD gets the file descriptor of the Program.
|
||||
//
|
||||
// It is invalid to call this function after Close has been called.
|
||||
func (p *Program) FD() int {
|
||||
fd, err := p.fd.Value()
|
||||
if err != nil {
|
||||
// Best effort: -1 is the number most likely to be an
|
||||
// invalid file descriptor.
|
||||
return -1
|
||||
}
|
||||
|
||||
return int(fd)
|
||||
return p.fd.Int()
|
||||
}
|
||||
|
||||
// Clone creates a duplicate of the Program.
|
||||
|
@ -345,9 +430,12 @@ func (p *Program) Clone() (*Program, error) {
|
|||
// Pin persists the Program on the BPF virtual file system past the lifetime of
|
||||
// the process that created it
|
||||
//
|
||||
// Calling Pin on a previously pinned program will overwrite the path, except when
|
||||
// the new path already exists. Re-pinning across filesystems is not supported.
|
||||
//
|
||||
// This requires bpffs to be mounted above fileName. See https://docs.cilium.io/en/k8s-doc/admin/#admin-mount-bpffs
|
||||
func (p *Program) Pin(fileName string) error {
|
||||
if err := pin(p.pinnedPath, fileName, p.fd); err != nil {
|
||||
if err := internal.Pin(p.pinnedPath, fileName, p.fd); err != nil {
|
||||
return err
|
||||
}
|
||||
p.pinnedPath = fileName
|
||||
|
@ -360,7 +448,7 @@ func (p *Program) Pin(fileName string) error {
|
|||
//
|
||||
// Unpinning an unpinned Program returns nil.
|
||||
func (p *Program) Unpin() error {
|
||||
if err := unpin(p.pinnedPath); err != nil {
|
||||
if err := internal.Unpin(p.pinnedPath); err != nil {
|
||||
return err
|
||||
}
|
||||
p.pinnedPath = ""
|
||||
|
@ -369,13 +457,12 @@ func (p *Program) Unpin() error {
|
|||
|
||||
// IsPinned returns true if the Program has a non-empty pinned path.
|
||||
func (p *Program) IsPinned() bool {
|
||||
if p.pinnedPath == "" {
|
||||
return false
|
||||
}
|
||||
return true
|
||||
return p.pinnedPath != ""
|
||||
}
|
||||
|
||||
// Close unloads the program from the kernel.
|
||||
// Close the Program's underlying file descriptor, which could unload
|
||||
// the program from the kernel if it is not pinned or attached to a
|
||||
// kernel hook.
|
||||
func (p *Program) Close() error {
|
||||
if p == nil {
|
||||
return nil
|
||||
|
@ -384,6 +471,28 @@ func (p *Program) Close() error {
|
|||
return p.fd.Close()
|
||||
}
|
||||
|
||||
// Various options for Run'ing a Program
|
||||
type RunOptions struct {
|
||||
// Program's data input. Required field.
|
||||
Data []byte
|
||||
// Program's data after Program has run. Caller must allocate. Optional field.
|
||||
DataOut []byte
|
||||
// Program's context input. Optional field.
|
||||
Context interface{}
|
||||
// Program's context after Program has run. Must be a pointer or slice. Optional field.
|
||||
ContextOut interface{}
|
||||
// Number of times to run Program. Optional field. Defaults to 1.
|
||||
Repeat uint32
|
||||
// Optional flags.
|
||||
Flags uint32
|
||||
// CPU to run Program on. Optional field.
|
||||
// Note not all program types support this field.
|
||||
CPU uint32
|
||||
// Called whenever the syscall is interrupted, and should be set to testing.B.ResetTimer
|
||||
// or similar. Typically used during benchmarking. Optional field.
|
||||
Reset func()
|
||||
}
|
||||
|
||||
// Test runs the Program in the kernel with the given input and returns the
|
||||
// value returned by the eBPF program. outLen may be zero.
|
||||
//
|
||||
|
@ -392,11 +501,38 @@ func (p *Program) Close() error {
|
|||
//
|
||||
// This function requires at least Linux 4.12.
|
||||
func (p *Program) Test(in []byte) (uint32, []byte, error) {
|
||||
ret, out, _, err := p.testRun(in, 1, nil)
|
||||
// Older kernels ignore the dataSizeOut argument when copying to user space.
|
||||
// Combined with things like bpf_xdp_adjust_head() we don't really know what the final
|
||||
// size will be. Hence we allocate an output buffer which we hope will always be large
|
||||
// enough, and panic if the kernel wrote past the end of the allocation.
|
||||
// See https://patchwork.ozlabs.org/cover/1006822/
|
||||
var out []byte
|
||||
if len(in) > 0 {
|
||||
out = make([]byte, len(in)+outputPad)
|
||||
}
|
||||
|
||||
opts := RunOptions{
|
||||
Data: in,
|
||||
DataOut: out,
|
||||
Repeat: 1,
|
||||
}
|
||||
|
||||
ret, _, err := p.testRun(&opts)
|
||||
if err != nil {
|
||||
return ret, nil, fmt.Errorf("can't test program: %w", err)
|
||||
}
|
||||
return ret, out, nil
|
||||
return ret, opts.DataOut, nil
|
||||
}
|
||||
|
||||
// Run runs the Program in kernel with given RunOptions.
|
||||
//
|
||||
// Note: the same restrictions from Test apply.
|
||||
func (p *Program) Run(opts *RunOptions) (uint32, error) {
|
||||
ret, _, err := p.testRun(opts)
|
||||
if err != nil {
|
||||
return ret, fmt.Errorf("can't test program: %w", err)
|
||||
}
|
||||
return ret, nil
|
||||
}
|
||||
|
||||
// Benchmark runs the Program with the given input for a number of times
|
||||
|
@ -411,7 +547,17 @@ func (p *Program) Test(in []byte) (uint32, []byte, error) {
|
|||
//
|
||||
// This function requires at least Linux 4.12.
|
||||
func (p *Program) Benchmark(in []byte, repeat int, reset func()) (uint32, time.Duration, error) {
|
||||
ret, _, total, err := p.testRun(in, repeat, reset)
|
||||
if uint(repeat) > math.MaxUint32 {
|
||||
return 0, 0, fmt.Errorf("repeat is too high")
|
||||
}
|
||||
|
||||
opts := RunOptions{
|
||||
Data: in,
|
||||
Repeat: uint32(repeat),
|
||||
Reset: reset,
|
||||
}
|
||||
|
||||
ret, total, err := p.testRun(&opts)
|
||||
if err != nil {
|
||||
return ret, total, fmt.Errorf("can't benchmark program: %w", err)
|
||||
}
|
||||
|
@ -420,6 +566,7 @@ func (p *Program) Benchmark(in []byte, repeat int, reset func()) (uint32, time.D
|
|||
|
||||
var haveProgTestRun = internal.FeatureTest("BPF_PROG_TEST_RUN", "4.12", func() error {
|
||||
prog, err := NewProgram(&ProgramSpec{
|
||||
// SocketFilter does not require privileges on newer kernels.
|
||||
Type: SocketFilter,
|
||||
Instructions: asm.Instructions{
|
||||
asm.LoadImm(asm.R0, 0, asm.DWord),
|
||||
|
@ -435,88 +582,109 @@ var haveProgTestRun = internal.FeatureTest("BPF_PROG_TEST_RUN", "4.12", func() e
|
|||
|
||||
// Programs require at least 14 bytes input
|
||||
in := make([]byte, 14)
|
||||
attr := bpfProgTestRunAttr{
|
||||
fd: uint32(prog.FD()),
|
||||
dataSizeIn: uint32(len(in)),
|
||||
dataIn: internal.NewSlicePointer(in),
|
||||
attr := sys.ProgRunAttr{
|
||||
ProgFd: uint32(prog.FD()),
|
||||
DataSizeIn: uint32(len(in)),
|
||||
DataIn: sys.NewSlicePointer(in),
|
||||
}
|
||||
|
||||
err = bpfProgTestRun(&attr)
|
||||
if errors.Is(err, unix.EINVAL) {
|
||||
err = sys.ProgRun(&attr)
|
||||
switch {
|
||||
case errors.Is(err, unix.EINVAL):
|
||||
// Check for EINVAL specifically, rather than err != nil since we
|
||||
// otherwise misdetect due to insufficient permissions.
|
||||
return internal.ErrNotSupported
|
||||
}
|
||||
if errors.Is(err, unix.EINTR) {
|
||||
|
||||
case errors.Is(err, unix.EINTR):
|
||||
// We know that PROG_TEST_RUN is supported if we get EINTR.
|
||||
return nil
|
||||
|
||||
case errors.Is(err, unix.ENOTSUPP):
|
||||
// The first PROG_TEST_RUN patches shipped in 4.12 didn't include
|
||||
// a test runner for SocketFilter. ENOTSUPP means PROG_TEST_RUN is
|
||||
// supported, but not for the program type used in the probe.
|
||||
return nil
|
||||
}
|
||||
|
||||
return err
|
||||
})
|
||||
|
||||
func (p *Program) testRun(in []byte, repeat int, reset func()) (uint32, []byte, time.Duration, error) {
|
||||
if uint(repeat) > math.MaxUint32 {
|
||||
return 0, nil, 0, fmt.Errorf("repeat is too high")
|
||||
}
|
||||
|
||||
if len(in) == 0 {
|
||||
return 0, nil, 0, fmt.Errorf("missing input")
|
||||
}
|
||||
|
||||
if uint(len(in)) > math.MaxUint32 {
|
||||
return 0, nil, 0, fmt.Errorf("input is too long")
|
||||
func (p *Program) testRun(opts *RunOptions) (uint32, time.Duration, error) {
|
||||
if uint(len(opts.Data)) > math.MaxUint32 {
|
||||
return 0, 0, fmt.Errorf("input is too long")
|
||||
}
|
||||
|
||||
if err := haveProgTestRun(); err != nil {
|
||||
return 0, nil, 0, err
|
||||
return 0, 0, err
|
||||
}
|
||||
|
||||
// Older kernels ignore the dataSizeOut argument when copying to user space.
|
||||
// Combined with things like bpf_xdp_adjust_head() we don't really know what the final
|
||||
// size will be. Hence we allocate an output buffer which we hope will always be large
|
||||
// enough, and panic if the kernel wrote past the end of the allocation.
|
||||
// See https://patchwork.ozlabs.org/cover/1006822/
|
||||
out := make([]byte, len(in)+outputPad)
|
||||
|
||||
fd, err := p.fd.Value()
|
||||
if err != nil {
|
||||
return 0, nil, 0, err
|
||||
var ctxBytes []byte
|
||||
if opts.Context != nil {
|
||||
ctx := new(bytes.Buffer)
|
||||
if err := binary.Write(ctx, internal.NativeEndian, opts.Context); err != nil {
|
||||
return 0, 0, fmt.Errorf("cannot serialize context: %v", err)
|
||||
}
|
||||
ctxBytes = ctx.Bytes()
|
||||
}
|
||||
|
||||
attr := bpfProgTestRunAttr{
|
||||
fd: fd,
|
||||
dataSizeIn: uint32(len(in)),
|
||||
dataSizeOut: uint32(len(out)),
|
||||
dataIn: internal.NewSlicePointer(in),
|
||||
dataOut: internal.NewSlicePointer(out),
|
||||
repeat: uint32(repeat),
|
||||
var ctxOut []byte
|
||||
if opts.ContextOut != nil {
|
||||
ctxOut = make([]byte, binary.Size(opts.ContextOut))
|
||||
}
|
||||
|
||||
attr := sys.ProgRunAttr{
|
||||
ProgFd: p.fd.Uint(),
|
||||
DataSizeIn: uint32(len(opts.Data)),
|
||||
DataSizeOut: uint32(len(opts.DataOut)),
|
||||
DataIn: sys.NewSlicePointer(opts.Data),
|
||||
DataOut: sys.NewSlicePointer(opts.DataOut),
|
||||
Repeat: uint32(opts.Repeat),
|
||||
CtxSizeIn: uint32(len(ctxBytes)),
|
||||
CtxSizeOut: uint32(len(ctxOut)),
|
||||
CtxIn: sys.NewSlicePointer(ctxBytes),
|
||||
CtxOut: sys.NewSlicePointer(ctxOut),
|
||||
Flags: opts.Flags,
|
||||
Cpu: opts.CPU,
|
||||
}
|
||||
|
||||
for {
|
||||
err = bpfProgTestRun(&attr)
|
||||
err := sys.ProgRun(&attr)
|
||||
if err == nil {
|
||||
break
|
||||
}
|
||||
|
||||
if errors.Is(err, unix.EINTR) {
|
||||
if reset != nil {
|
||||
reset()
|
||||
if opts.Reset != nil {
|
||||
opts.Reset()
|
||||
}
|
||||
continue
|
||||
}
|
||||
|
||||
return 0, nil, 0, fmt.Errorf("can't run test: %w", err)
|
||||
if errors.Is(err, unix.ENOTSUPP) {
|
||||
return 0, 0, fmt.Errorf("kernel doesn't support testing program type %s: %w", p.Type(), ErrNotSupported)
|
||||
}
|
||||
|
||||
if int(attr.dataSizeOut) > cap(out) {
|
||||
return 0, 0, fmt.Errorf("can't run test: %w", err)
|
||||
}
|
||||
|
||||
if opts.DataOut != nil {
|
||||
if int(attr.DataSizeOut) > cap(opts.DataOut) {
|
||||
// Houston, we have a problem. The program created more data than we allocated,
|
||||
// and the kernel wrote past the end of our buffer.
|
||||
panic("kernel wrote past end of output buffer")
|
||||
}
|
||||
out = out[:int(attr.dataSizeOut)]
|
||||
opts.DataOut = opts.DataOut[:int(attr.DataSizeOut)]
|
||||
}
|
||||
|
||||
total := time.Duration(attr.duration) * time.Nanosecond
|
||||
return attr.retval, out, total, nil
|
||||
if len(ctxOut) != 0 {
|
||||
b := bytes.NewReader(ctxOut)
|
||||
if err := binary.Read(b, internal.NativeEndian, opts.ContextOut); err != nil {
|
||||
return 0, 0, fmt.Errorf("failed to decode ContextOut: %v", err)
|
||||
}
|
||||
}
|
||||
|
||||
total := time.Duration(attr.Duration) * time.Nanosecond
|
||||
return attr.Retval, total, nil
|
||||
}
|
||||
|
||||
func unmarshalProgram(buf []byte) (*Program, error) {
|
||||
|
@ -535,70 +703,19 @@ func marshalProgram(p *Program, length int) ([]byte, error) {
|
|||
return nil, fmt.Errorf("can't marshal program to %d bytes", length)
|
||||
}
|
||||
|
||||
value, err := p.fd.Value()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
buf := make([]byte, 4)
|
||||
internal.NativeEndian.PutUint32(buf, value)
|
||||
internal.NativeEndian.PutUint32(buf, p.fd.Uint())
|
||||
return buf, nil
|
||||
}
|
||||
|
||||
// Attach a Program.
|
||||
//
|
||||
// Deprecated: use link.RawAttachProgram instead.
|
||||
func (p *Program) Attach(fd int, typ AttachType, flags AttachFlags) error {
|
||||
if fd < 0 {
|
||||
return errors.New("invalid fd")
|
||||
}
|
||||
|
||||
pfd, err := p.fd.Value()
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
attr := internal.BPFProgAttachAttr{
|
||||
TargetFd: uint32(fd),
|
||||
AttachBpfFd: pfd,
|
||||
AttachType: uint32(typ),
|
||||
AttachFlags: uint32(flags),
|
||||
}
|
||||
|
||||
return internal.BPFProgAttach(&attr)
|
||||
}
|
||||
|
||||
// Detach a Program.
|
||||
//
|
||||
// Deprecated: use link.RawDetachProgram instead.
|
||||
func (p *Program) Detach(fd int, typ AttachType, flags AttachFlags) error {
|
||||
if fd < 0 {
|
||||
return errors.New("invalid fd")
|
||||
}
|
||||
|
||||
if flags != 0 {
|
||||
return errors.New("flags must be zero")
|
||||
}
|
||||
|
||||
pfd, err := p.fd.Value()
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
attr := internal.BPFProgDetachAttr{
|
||||
TargetFd: uint32(fd),
|
||||
AttachBpfFd: pfd,
|
||||
AttachType: uint32(typ),
|
||||
}
|
||||
|
||||
return internal.BPFProgDetach(&attr)
|
||||
}
|
||||
|
||||
// LoadPinnedProgram loads a Program from a BPF file.
|
||||
//
|
||||
// Requires at least Linux 4.11.
|
||||
func LoadPinnedProgram(fileName string) (*Program, error) {
|
||||
fd, err := internal.BPFObjGet(fileName)
|
||||
func LoadPinnedProgram(fileName string, opts *LoadPinOptions) (*Program, error) {
|
||||
fd, err := sys.ObjGet(&sys.ObjGetAttr{
|
||||
Pathname: sys.NewStringPointer(fileName),
|
||||
FileFlags: opts.Marshal(),
|
||||
})
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
@ -609,7 +726,7 @@ func LoadPinnedProgram(fileName string) (*Program, error) {
|
|||
return nil, fmt.Errorf("info for %s: %w", fileName, err)
|
||||
}
|
||||
|
||||
return &Program{"", fd, filepath.Base(fileName), "", info.Type}, nil
|
||||
return &Program{"", fd, filepath.Base(fileName), fileName, info.Type}, nil
|
||||
}
|
||||
|
||||
// SanitizeName replaces all invalid characters in name with replacement.
|
||||
|
@ -632,67 +749,127 @@ func SanitizeName(name string, replacement rune) string {
|
|||
//
|
||||
// Returns ErrNotExist, if there is no next eBPF program.
|
||||
func ProgramGetNextID(startID ProgramID) (ProgramID, error) {
|
||||
id, err := objGetNextID(internal.BPF_PROG_GET_NEXT_ID, uint32(startID))
|
||||
return ProgramID(id), err
|
||||
attr := &sys.ProgGetNextIdAttr{Id: uint32(startID)}
|
||||
return ProgramID(attr.NextId), sys.ProgGetNextId(attr)
|
||||
}
|
||||
|
||||
// ID returns the systemwide unique ID of the program.
|
||||
// BindMap binds map to the program and is only released once program is released.
|
||||
//
|
||||
// Deprecated: use ProgramInfo.ID() instead.
|
||||
func (p *Program) ID() (ProgramID, error) {
|
||||
info, err := bpfGetProgInfoByFD(p.fd)
|
||||
if err != nil {
|
||||
return ProgramID(0), err
|
||||
}
|
||||
return ProgramID(info.id), nil
|
||||
// This may be used in cases where metadata should be associated with the program
|
||||
// which otherwise does not contain any references to the map.
|
||||
func (p *Program) BindMap(m *Map) error {
|
||||
attr := &sys.ProgBindMapAttr{
|
||||
ProgFd: uint32(p.FD()),
|
||||
MapFd: uint32(m.FD()),
|
||||
}
|
||||
|
||||
func findKernelType(name string, typ btf.Type) error {
|
||||
kernel, err := btf.LoadKernelSpec()
|
||||
if err != nil {
|
||||
return fmt.Errorf("can't load kernel spec: %w", err)
|
||||
return sys.ProgBindMap(attr)
|
||||
}
|
||||
|
||||
return kernel.FindType(name, typ)
|
||||
}
|
||||
var errUnrecognizedAttachType = errors.New("unrecognized attach type")
|
||||
|
||||
func resolveBTFType(name string, progType ProgramType, attachType AttachType) (btf.Type, error) {
|
||||
// find an attach target type in the kernel.
|
||||
//
|
||||
// spec may be nil and defaults to the canonical kernel BTF. name together with
|
||||
// progType and attachType determine which type we need to attach to.
|
||||
//
|
||||
// Returns errUnrecognizedAttachType.
|
||||
func findTargetInKernel(spec *btf.Spec, name string, progType ProgramType, attachType AttachType) (btf.TypeID, error) {
|
||||
type match struct {
|
||||
p ProgramType
|
||||
a AttachType
|
||||
}
|
||||
|
||||
target := match{progType, attachType}
|
||||
switch target {
|
||||
var (
|
||||
typeName, featureName string
|
||||
isBTFTypeFunc = true
|
||||
)
|
||||
|
||||
switch (match{progType, attachType}) {
|
||||
case match{LSM, AttachLSMMac}:
|
||||
var target btf.Func
|
||||
err := findKernelType("bpf_lsm_"+name, &target)
|
||||
if errors.Is(err, btf.ErrNotFound) {
|
||||
return nil, &internal.UnsupportedFeatureError{
|
||||
Name: name + " LSM hook",
|
||||
}
|
||||
}
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("resolve BTF for LSM hook %s: %w", name, err)
|
||||
}
|
||||
|
||||
return &target, nil
|
||||
|
||||
typeName = "bpf_lsm_" + name
|
||||
featureName = name + " LSM hook"
|
||||
case match{Tracing, AttachTraceIter}:
|
||||
var target btf.Func
|
||||
err := findKernelType("bpf_iter_"+name, &target)
|
||||
if errors.Is(err, btf.ErrNotFound) {
|
||||
return nil, &internal.UnsupportedFeatureError{
|
||||
Name: name + " iterator",
|
||||
}
|
||||
}
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("resolve BTF for iterator %s: %w", name, err)
|
||||
}
|
||||
|
||||
return &target, nil
|
||||
|
||||
typeName = "bpf_iter_" + name
|
||||
featureName = name + " iterator"
|
||||
case match{Tracing, AttachTraceFEntry}:
|
||||
typeName = name
|
||||
featureName = fmt.Sprintf("fentry %s", name)
|
||||
case match{Tracing, AttachTraceFExit}:
|
||||
typeName = name
|
||||
featureName = fmt.Sprintf("fexit %s", name)
|
||||
case match{Tracing, AttachModifyReturn}:
|
||||
typeName = name
|
||||
featureName = fmt.Sprintf("fmod_ret %s", name)
|
||||
case match{Tracing, AttachTraceRawTp}:
|
||||
typeName = fmt.Sprintf("btf_trace_%s", name)
|
||||
featureName = fmt.Sprintf("raw_tp %s", name)
|
||||
isBTFTypeFunc = false
|
||||
default:
|
||||
return nil, nil
|
||||
return 0, errUnrecognizedAttachType
|
||||
}
|
||||
|
||||
spec, err := maybeLoadKernelBTF(spec)
|
||||
if err != nil {
|
||||
return 0, fmt.Errorf("load kernel spec: %w", err)
|
||||
}
|
||||
|
||||
var target btf.Type
|
||||
if isBTFTypeFunc {
|
||||
var targetFunc *btf.Func
|
||||
err = spec.TypeByName(typeName, &targetFunc)
|
||||
target = targetFunc
|
||||
} else {
|
||||
var targetTypedef *btf.Typedef
|
||||
err = spec.TypeByName(typeName, &targetTypedef)
|
||||
target = targetTypedef
|
||||
}
|
||||
|
||||
if err != nil {
|
||||
if errors.Is(err, btf.ErrNotFound) {
|
||||
return 0, &internal.UnsupportedFeatureError{
|
||||
Name: featureName,
|
||||
}
|
||||
}
|
||||
return 0, fmt.Errorf("find target for %s: %w", featureName, err)
|
||||
}
|
||||
|
||||
return spec.TypeID(target)
|
||||
}
|
||||
|
||||
// find an attach target type in a program.
|
||||
//
|
||||
// Returns errUnrecognizedAttachType.
|
||||
func findTargetInProgram(prog *Program, name string, progType ProgramType, attachType AttachType) (btf.TypeID, error) {
|
||||
type match struct {
|
||||
p ProgramType
|
||||
a AttachType
|
||||
}
|
||||
|
||||
var typeName string
|
||||
switch (match{progType, attachType}) {
|
||||
case match{Extension, AttachNone}:
|
||||
typeName = name
|
||||
default:
|
||||
return 0, errUnrecognizedAttachType
|
||||
}
|
||||
|
||||
btfHandle, err := prog.Handle()
|
||||
if err != nil {
|
||||
return 0, fmt.Errorf("load target BTF: %w", err)
|
||||
}
|
||||
defer btfHandle.Close()
|
||||
|
||||
spec, err := btfHandle.Spec(nil)
|
||||
if err != nil {
|
||||
return 0, err
|
||||
}
|
||||
|
||||
var targetFunc *btf.Func
|
||||
err = spec.TypeByName(typeName, &targetFunc)
|
||||
if err != nil {
|
||||
return 0, fmt.Errorf("find target %s: %w", typeName, err)
|
||||
}
|
||||
|
||||
return spec.TypeID(targetFunc)
|
||||
}
|
||||
|
|
|
@ -1,38 +1,33 @@
|
|||
#!/bin/bash
|
||||
#!/usr/bin/env bash
|
||||
# Test the current package under a different kernel.
|
||||
# Requires virtme and qemu to be installed.
|
||||
# Examples:
|
||||
# Run all tests on a 5.4 kernel
|
||||
# $ ./run-tests.sh 5.4
|
||||
# Run a subset of tests:
|
||||
# $ ./run-tests.sh 5.4 ./link
|
||||
|
||||
set -eu
|
||||
set -o pipefail
|
||||
set -euo pipefail
|
||||
|
||||
if [[ "${1:-}" = "--in-vm" ]]; then
|
||||
script="$(realpath "$0")"
|
||||
readonly script
|
||||
|
||||
# This script is a bit like a Matryoshka doll since it keeps re-executing itself
|
||||
# in various different contexts:
|
||||
#
|
||||
# 1. invoked by the user like run-tests.sh 5.4
|
||||
# 2. invoked by go test like run-tests.sh --exec-vm
|
||||
# 3. invoked by init in the vm like run-tests.sh --exec-test
|
||||
#
|
||||
# This allows us to use all available CPU on the host machine to compile our
|
||||
# code, and then only use the VM to execute the test. This is because the VM
|
||||
# is usually slower at compiling than the host.
|
||||
if [[ "${1:-}" = "--exec-vm" ]]; then
|
||||
shift
|
||||
|
||||
mount -t bpf bpf /sys/fs/bpf
|
||||
export CGO_ENABLED=0
|
||||
export GOFLAGS=-mod=readonly
|
||||
export GOPATH=/run/go-path
|
||||
export GOPROXY=file:///run/go-path/pkg/mod/cache/download
|
||||
export GOSUMDB=off
|
||||
export GOCACHE=/run/go-cache
|
||||
|
||||
if [[ -d "/run/input/bpf" ]]; then
|
||||
export KERNEL_SELFTESTS="/run/input/bpf"
|
||||
fi
|
||||
|
||||
readonly output="${1}"
|
||||
input="$1"
|
||||
shift
|
||||
|
||||
echo Running tests...
|
||||
go test -v -coverpkg=./... -coverprofile="$output/coverage.txt" -count 1 ./...
|
||||
touch "$output/success"
|
||||
exit 0
|
||||
fi
|
||||
|
||||
# Pull all dependencies, so that we can run tests without the
|
||||
# vm having network access.
|
||||
go mod download
|
||||
|
||||
# Use sudo if /dev/kvm isn't accessible by the current user.
|
||||
sudo=""
|
||||
if [[ ! -r /dev/kvm || ! -w /dev/kvm ]]; then
|
||||
|
@ -40,52 +35,111 @@ if [[ ! -r /dev/kvm || ! -w /dev/kvm ]]; then
|
|||
fi
|
||||
readonly sudo
|
||||
|
||||
testdir="$(dirname "$1")"
|
||||
output="$(mktemp -d)"
|
||||
printf -v cmd "%q " "$@"
|
||||
|
||||
if [[ "$(stat -c '%t:%T' -L /proc/$$/fd/0)" == "1:3" ]]; then
|
||||
# stdin is /dev/null, which doesn't play well with qemu. Use a fifo as a
|
||||
# blocking substitute.
|
||||
mkfifo "${output}/fake-stdin"
|
||||
# Open for reading and writing to avoid blocking.
|
||||
exec 0<> "${output}/fake-stdin"
|
||||
rm "${output}/fake-stdin"
|
||||
fi
|
||||
|
||||
for ((i = 0; i < 3; i++)); do
|
||||
if ! $sudo virtme-run --kimg "${input}/bzImage" --memory 768M --pwd \
|
||||
--rwdir="${testdir}=${testdir}" \
|
||||
--rodir=/run/input="${input}" \
|
||||
--rwdir=/run/output="${output}" \
|
||||
--script-sh "PATH=\"$PATH\" CI_MAX_KERNEL_VERSION="${CI_MAX_KERNEL_VERSION:-}" \"$script\" --exec-test $cmd" \
|
||||
--kopt possible_cpus=2; then # need at least two CPUs for some tests
|
||||
exit 23
|
||||
fi
|
||||
|
||||
if [[ -e "${output}/status" ]]; then
|
||||
break
|
||||
fi
|
||||
|
||||
if [[ -v CI ]]; then
|
||||
echo "Retrying test run due to qemu crash"
|
||||
continue
|
||||
fi
|
||||
|
||||
exit 42
|
||||
done
|
||||
|
||||
rc=$(<"${output}/status")
|
||||
$sudo rm -r "$output"
|
||||
exit $rc
|
||||
elif [[ "${1:-}" = "--exec-test" ]]; then
|
||||
shift
|
||||
|
||||
mount -t bpf bpf /sys/fs/bpf
|
||||
mount -t tracefs tracefs /sys/kernel/debug/tracing
|
||||
|
||||
if [[ -d "/run/input/bpf" ]]; then
|
||||
export KERNEL_SELFTESTS="/run/input/bpf"
|
||||
fi
|
||||
|
||||
if [[ -f "/run/input/bpf/bpf_testmod/bpf_testmod.ko" ]]; then
|
||||
insmod "/run/input/bpf/bpf_testmod/bpf_testmod.ko"
|
||||
fi
|
||||
|
||||
dmesg --clear
|
||||
rc=0
|
||||
"$@" || rc=$?
|
||||
dmesg
|
||||
echo $rc > "/run/output/status"
|
||||
exit $rc # this return code is "swallowed" by qemu
|
||||
fi
|
||||
|
||||
readonly kernel_version="${1:-}"
|
||||
if [[ -z "${kernel_version}" ]]; then
|
||||
echo "Expecting kernel version as first argument"
|
||||
exit 1
|
||||
fi
|
||||
shift
|
||||
|
||||
readonly kernel="linux-${kernel_version}.bz"
|
||||
readonly selftests="linux-${kernel_version}-selftests-bpf.bz"
|
||||
readonly selftests="linux-${kernel_version}-selftests-bpf.tgz"
|
||||
readonly input="$(mktemp -d)"
|
||||
readonly output="$(mktemp -d)"
|
||||
readonly tmp_dir="${TMPDIR:-/tmp}"
|
||||
readonly branch="${BRANCH:-master}"
|
||||
|
||||
fetch() {
|
||||
echo Fetching "${1}"
|
||||
wget -nv -N -P "${tmp_dir}" "https://github.com/cilium/ci-kernels/raw/${branch}/${1}"
|
||||
pushd "${tmp_dir}" > /dev/null
|
||||
curl -s -L -O --fail --etag-compare "${1}.etag" --etag-save "${1}.etag" "https://github.com/cilium/ci-kernels/raw/${branch}/${1}"
|
||||
local ret=$?
|
||||
popd > /dev/null
|
||||
return $ret
|
||||
}
|
||||
|
||||
fetch "${kernel}"
|
||||
cp "${tmp_dir}/${kernel}" "${input}/bzImage"
|
||||
|
||||
if fetch "${selftests}"; then
|
||||
echo "Decompressing selftests"
|
||||
mkdir "${input}/bpf"
|
||||
tar --strip-components=4 -xjf "${tmp_dir}/${selftests}" -C "${input}/bpf"
|
||||
tar --strip-components=4 -xf "${tmp_dir}/${selftests}" -C "${input}/bpf"
|
||||
else
|
||||
echo "No selftests found, disabling"
|
||||
fi
|
||||
|
||||
args=(-short -coverpkg=./... -coverprofile=coverage.out -count 1 ./...)
|
||||
if (( $# > 0 )); then
|
||||
args=("$@")
|
||||
fi
|
||||
|
||||
export GOFLAGS=-mod=readonly
|
||||
export CGO_ENABLED=0
|
||||
# LINUX_VERSION_CODE test compares this to discovered value.
|
||||
export KERNEL_VERSION="${kernel_version}"
|
||||
|
||||
echo Testing on "${kernel_version}"
|
||||
$sudo virtme-run --kimg "${tmp_dir}/${kernel}" --memory 512M --pwd \
|
||||
--rw \
|
||||
--rwdir=/run/input="${input}" \
|
||||
--rwdir=/run/output="${output}" \
|
||||
--rodir=/run/go-path="$(go env GOPATH)" \
|
||||
--rwdir=/run/go-cache="$(go env GOCACHE)" \
|
||||
--script-sh "PATH=\"$PATH\" $(realpath "$0") --in-vm /run/output" \
|
||||
--qemu-opts -smp 2 # need at least two CPUs for some tests
|
||||
|
||||
if [[ ! -e "${output}/success" ]]; then
|
||||
echo "Test failed on ${kernel_version}"
|
||||
exit 1
|
||||
else
|
||||
go test -exec "$script --exec-vm $input" "${args[@]}"
|
||||
echo "Test successful on ${kernel_version}"
|
||||
if [[ -v COVERALLS_TOKEN ]]; then
|
||||
goveralls -coverprofile="${output}/coverage.txt" -service=semaphore -repotoken "$COVERALLS_TOKEN"
|
||||
fi
|
||||
fi
|
||||
|
||||
$sudo rm -r "${input}"
|
||||
$sudo rm -r "${output}"
|
||||
rm -r "${input}"
|
||||
|
|
|
@ -1,29 +1,16 @@
|
|||
package ebpf
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"errors"
|
||||
"fmt"
|
||||
"unsafe"
|
||||
|
||||
"github.com/cilium/ebpf/asm"
|
||||
"github.com/cilium/ebpf/internal"
|
||||
"github.com/cilium/ebpf/internal/btf"
|
||||
"github.com/cilium/ebpf/internal/sys"
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
// Generic errors returned by BPF syscalls.
|
||||
var ErrNotExist = errors.New("requested object does not exist")
|
||||
|
||||
// bpfObjName is a null-terminated string made up of
|
||||
// 'A-Za-z0-9_' characters.
|
||||
type bpfObjName [unix.BPF_OBJ_NAME_LEN]byte
|
||||
|
||||
// newBPFObjName truncates the result if it is too long.
|
||||
func newBPFObjName(name string) bpfObjName {
|
||||
var result bpfObjName
|
||||
copy(result[:unix.BPF_OBJ_NAME_LEN-1], name)
|
||||
return result
|
||||
}
|
||||
|
||||
// invalidBPFObjNameChar returns true if char may not appear in
|
||||
// a BPF object name.
|
||||
func invalidBPFObjNameChar(char rune) bool {
|
||||
|
@ -45,183 +32,29 @@ func invalidBPFObjNameChar(char rune) bool {
|
|||
}
|
||||
}
|
||||
|
||||
type bpfMapCreateAttr struct {
|
||||
mapType MapType
|
||||
keySize uint32
|
||||
valueSize uint32
|
||||
maxEntries uint32
|
||||
flags uint32
|
||||
innerMapFd uint32 // since 4.12 56f668dfe00d
|
||||
numaNode uint32 // since 4.14 96eabe7a40aa
|
||||
mapName bpfObjName // since 4.15 ad5b177bd73f
|
||||
mapIfIndex uint32
|
||||
btfFd uint32
|
||||
btfKeyTypeID btf.TypeID
|
||||
btfValueTypeID btf.TypeID
|
||||
}
|
||||
|
||||
type bpfMapOpAttr struct {
|
||||
mapFd uint32
|
||||
padding uint32
|
||||
key internal.Pointer
|
||||
value internal.Pointer
|
||||
flags uint64
|
||||
}
|
||||
|
||||
type bpfBatchMapOpAttr struct {
|
||||
inBatch internal.Pointer
|
||||
outBatch internal.Pointer
|
||||
keys internal.Pointer
|
||||
values internal.Pointer
|
||||
count uint32
|
||||
mapFd uint32
|
||||
elemFlags uint64
|
||||
flags uint64
|
||||
}
|
||||
|
||||
type bpfMapInfo struct {
|
||||
map_type uint32 // since 4.12 1e2709769086
|
||||
id uint32
|
||||
key_size uint32
|
||||
value_size uint32
|
||||
max_entries uint32
|
||||
map_flags uint32
|
||||
name bpfObjName // since 4.15 ad5b177bd73f
|
||||
ifindex uint32 // since 4.16 52775b33bb50
|
||||
btf_vmlinux_value_type_id uint32 // since 5.6 85d33df357b6
|
||||
netns_dev uint64 // since 4.16 52775b33bb50
|
||||
netns_ino uint64
|
||||
btf_id uint32 // since 4.18 78958fca7ead
|
||||
btf_key_type_id uint32 // since 4.18 9b2cf328b2ec
|
||||
btf_value_type_id uint32
|
||||
}
|
||||
|
||||
type bpfProgLoadAttr struct {
|
||||
progType ProgramType
|
||||
insCount uint32
|
||||
instructions internal.Pointer
|
||||
license internal.Pointer
|
||||
logLevel uint32
|
||||
logSize uint32
|
||||
logBuf internal.Pointer
|
||||
kernelVersion uint32 // since 4.1 2541517c32be
|
||||
progFlags uint32 // since 4.11 e07b98d9bffe
|
||||
progName bpfObjName // since 4.15 067cae47771c
|
||||
progIfIndex uint32 // since 4.15 1f6f4cb7ba21
|
||||
expectedAttachType AttachType // since 4.17 5e43f899b03a
|
||||
progBTFFd uint32
|
||||
funcInfoRecSize uint32
|
||||
funcInfo internal.Pointer
|
||||
funcInfoCnt uint32
|
||||
lineInfoRecSize uint32
|
||||
lineInfo internal.Pointer
|
||||
lineInfoCnt uint32
|
||||
attachBTFID btf.TypeID
|
||||
attachProgFd uint32
|
||||
}
|
||||
|
||||
type bpfProgInfo struct {
|
||||
prog_type uint32
|
||||
id uint32
|
||||
tag [unix.BPF_TAG_SIZE]byte
|
||||
jited_prog_len uint32
|
||||
xlated_prog_len uint32
|
||||
jited_prog_insns internal.Pointer
|
||||
xlated_prog_insns internal.Pointer
|
||||
load_time uint64 // since 4.15 cb4d2b3f03d8
|
||||
created_by_uid uint32
|
||||
nr_map_ids uint32
|
||||
map_ids internal.Pointer
|
||||
name bpfObjName // since 4.15 067cae47771c
|
||||
ifindex uint32
|
||||
gpl_compatible uint32
|
||||
netns_dev uint64
|
||||
netns_ino uint64
|
||||
nr_jited_ksyms uint32
|
||||
nr_jited_func_lens uint32
|
||||
jited_ksyms internal.Pointer
|
||||
jited_func_lens internal.Pointer
|
||||
btf_id uint32
|
||||
func_info_rec_size uint32
|
||||
func_info internal.Pointer
|
||||
nr_func_info uint32
|
||||
nr_line_info uint32
|
||||
line_info internal.Pointer
|
||||
jited_line_info internal.Pointer
|
||||
nr_jited_line_info uint32
|
||||
line_info_rec_size uint32
|
||||
jited_line_info_rec_size uint32
|
||||
nr_prog_tags uint32
|
||||
prog_tags internal.Pointer
|
||||
run_time_ns uint64
|
||||
run_cnt uint64
|
||||
}
|
||||
|
||||
type bpfProgTestRunAttr struct {
|
||||
fd uint32
|
||||
retval uint32
|
||||
dataSizeIn uint32
|
||||
dataSizeOut uint32
|
||||
dataIn internal.Pointer
|
||||
dataOut internal.Pointer
|
||||
repeat uint32
|
||||
duration uint32
|
||||
}
|
||||
|
||||
type bpfGetFDByIDAttr struct {
|
||||
id uint32
|
||||
next uint32
|
||||
}
|
||||
|
||||
type bpfMapFreezeAttr struct {
|
||||
mapFd uint32
|
||||
}
|
||||
|
||||
type bpfObjGetNextIDAttr struct {
|
||||
startID uint32
|
||||
nextID uint32
|
||||
openFlags uint32
|
||||
}
|
||||
|
||||
func bpfProgLoad(attr *bpfProgLoadAttr) (*internal.FD, error) {
|
||||
for {
|
||||
fd, err := internal.BPF(internal.BPF_PROG_LOAD, unsafe.Pointer(attr), unsafe.Sizeof(*attr))
|
||||
// As of ~4.20 the verifier can be interrupted by a signal,
|
||||
// and returns EAGAIN in that case.
|
||||
if err == unix.EAGAIN {
|
||||
continue
|
||||
}
|
||||
|
||||
if err != nil {
|
||||
func progLoad(insns asm.Instructions, typ ProgramType, license string) (*sys.FD, error) {
|
||||
buf := bytes.NewBuffer(make([]byte, 0, insns.Size()))
|
||||
if err := insns.Marshal(buf, internal.NativeEndian); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
bytecode := buf.Bytes()
|
||||
|
||||
return internal.NewFD(uint32(fd)), nil
|
||||
}
|
||||
}
|
||||
|
||||
func bpfProgTestRun(attr *bpfProgTestRunAttr) error {
|
||||
_, err := internal.BPF(internal.BPF_PROG_TEST_RUN, unsafe.Pointer(attr), unsafe.Sizeof(*attr))
|
||||
return err
|
||||
}
|
||||
|
||||
func bpfMapCreate(attr *bpfMapCreateAttr) (*internal.FD, error) {
|
||||
fd, err := internal.BPF(internal.BPF_MAP_CREATE, unsafe.Pointer(attr), unsafe.Sizeof(*attr))
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return internal.NewFD(uint32(fd)), nil
|
||||
return sys.ProgLoad(&sys.ProgLoadAttr{
|
||||
ProgType: sys.ProgType(typ),
|
||||
License: sys.NewStringPointer(license),
|
||||
Insns: sys.NewSlicePointer(bytecode),
|
||||
InsnCnt: uint32(len(bytecode) / asm.InstructionSize),
|
||||
})
|
||||
}
|
||||
|
||||
var haveNestedMaps = internal.FeatureTest("nested maps", "4.12", func() error {
|
||||
_, err := bpfMapCreate(&bpfMapCreateAttr{
|
||||
mapType: ArrayOfMaps,
|
||||
keySize: 4,
|
||||
valueSize: 4,
|
||||
maxEntries: 1,
|
||||
_, err := sys.MapCreate(&sys.MapCreateAttr{
|
||||
MapType: sys.MapType(ArrayOfMaps),
|
||||
KeySize: 4,
|
||||
ValueSize: 4,
|
||||
MaxEntries: 1,
|
||||
// Invalid file descriptor.
|
||||
innerMapFd: ^uint32(0),
|
||||
InnerMapFd: ^uint32(0),
|
||||
})
|
||||
if errors.Is(err, unix.EINVAL) {
|
||||
return internal.ErrNotSupported
|
||||
|
@ -235,12 +68,12 @@ var haveNestedMaps = internal.FeatureTest("nested maps", "4.12", func() error {
|
|||
var haveMapMutabilityModifiers = internal.FeatureTest("read- and write-only maps", "5.2", func() error {
|
||||
// This checks BPF_F_RDONLY_PROG and BPF_F_WRONLY_PROG. Since
|
||||
// BPF_MAP_FREEZE appeared in 5.2 as well we don't do a separate check.
|
||||
m, err := bpfMapCreate(&bpfMapCreateAttr{
|
||||
mapType: Array,
|
||||
keySize: 4,
|
||||
valueSize: 4,
|
||||
maxEntries: 1,
|
||||
flags: unix.BPF_F_RDONLY_PROG,
|
||||
m, err := sys.MapCreate(&sys.MapCreateAttr{
|
||||
MapType: sys.MapType(Array),
|
||||
KeySize: 4,
|
||||
ValueSize: 4,
|
||||
MaxEntries: 1,
|
||||
MapFlags: unix.BPF_F_RDONLY_PROG,
|
||||
})
|
||||
if err != nil {
|
||||
return internal.ErrNotSupported
|
||||
|
@ -249,122 +82,53 @@ var haveMapMutabilityModifiers = internal.FeatureTest("read- and write-only maps
|
|||
return nil
|
||||
})
|
||||
|
||||
func bpfMapLookupElem(m *internal.FD, key, valueOut internal.Pointer) error {
|
||||
fd, err := m.Value()
|
||||
var haveMmapableMaps = internal.FeatureTest("mmapable maps", "5.5", func() error {
|
||||
// This checks BPF_F_MMAPABLE, which appeared in 5.5 for array maps.
|
||||
m, err := sys.MapCreate(&sys.MapCreateAttr{
|
||||
MapType: sys.MapType(Array),
|
||||
KeySize: 4,
|
||||
ValueSize: 4,
|
||||
MaxEntries: 1,
|
||||
MapFlags: unix.BPF_F_MMAPABLE,
|
||||
})
|
||||
if err != nil {
|
||||
return err
|
||||
return internal.ErrNotSupported
|
||||
}
|
||||
|
||||
attr := bpfMapOpAttr{
|
||||
mapFd: fd,
|
||||
key: key,
|
||||
value: valueOut,
|
||||
}
|
||||
_, err = internal.BPF(internal.BPF_MAP_LOOKUP_ELEM, unsafe.Pointer(&attr), unsafe.Sizeof(attr))
|
||||
return wrapMapError(err)
|
||||
}
|
||||
|
||||
func bpfMapLookupAndDelete(m *internal.FD, key, valueOut internal.Pointer) error {
|
||||
fd, err := m.Value()
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
attr := bpfMapOpAttr{
|
||||
mapFd: fd,
|
||||
key: key,
|
||||
value: valueOut,
|
||||
}
|
||||
_, err = internal.BPF(internal.BPF_MAP_LOOKUP_AND_DELETE_ELEM, unsafe.Pointer(&attr), unsafe.Sizeof(attr))
|
||||
return wrapMapError(err)
|
||||
}
|
||||
|
||||
func bpfMapUpdateElem(m *internal.FD, key, valueOut internal.Pointer, flags uint64) error {
|
||||
fd, err := m.Value()
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
attr := bpfMapOpAttr{
|
||||
mapFd: fd,
|
||||
key: key,
|
||||
value: valueOut,
|
||||
flags: flags,
|
||||
}
|
||||
_, err = internal.BPF(internal.BPF_MAP_UPDATE_ELEM, unsafe.Pointer(&attr), unsafe.Sizeof(attr))
|
||||
return wrapMapError(err)
|
||||
}
|
||||
|
||||
func bpfMapDeleteElem(m *internal.FD, key internal.Pointer) error {
|
||||
fd, err := m.Value()
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
attr := bpfMapOpAttr{
|
||||
mapFd: fd,
|
||||
key: key,
|
||||
}
|
||||
_, err = internal.BPF(internal.BPF_MAP_DELETE_ELEM, unsafe.Pointer(&attr), unsafe.Sizeof(attr))
|
||||
return wrapMapError(err)
|
||||
}
|
||||
|
||||
func bpfMapGetNextKey(m *internal.FD, key, nextKeyOut internal.Pointer) error {
|
||||
fd, err := m.Value()
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
attr := bpfMapOpAttr{
|
||||
mapFd: fd,
|
||||
key: key,
|
||||
value: nextKeyOut,
|
||||
}
|
||||
_, err = internal.BPF(internal.BPF_MAP_GET_NEXT_KEY, unsafe.Pointer(&attr), unsafe.Sizeof(attr))
|
||||
return wrapMapError(err)
|
||||
}
|
||||
|
||||
func objGetNextID(cmd internal.BPFCmd, start uint32) (uint32, error) {
|
||||
attr := bpfObjGetNextIDAttr{
|
||||
startID: start,
|
||||
}
|
||||
_, err := internal.BPF(cmd, unsafe.Pointer(&attr), unsafe.Sizeof(attr))
|
||||
return attr.nextID, wrapObjError(err)
|
||||
}
|
||||
|
||||
func bpfMapBatch(cmd internal.BPFCmd, m *internal.FD, inBatch, outBatch, keys, values internal.Pointer, count uint32, opts *BatchOptions) (uint32, error) {
|
||||
fd, err := m.Value()
|
||||
if err != nil {
|
||||
return 0, err
|
||||
}
|
||||
|
||||
attr := bpfBatchMapOpAttr{
|
||||
inBatch: inBatch,
|
||||
outBatch: outBatch,
|
||||
keys: keys,
|
||||
values: values,
|
||||
count: count,
|
||||
mapFd: fd,
|
||||
}
|
||||
if opts != nil {
|
||||
attr.elemFlags = opts.ElemFlags
|
||||
attr.flags = opts.Flags
|
||||
}
|
||||
_, err = internal.BPF(cmd, unsafe.Pointer(&attr), unsafe.Sizeof(attr))
|
||||
// always return count even on an error, as things like update might partially be fulfilled.
|
||||
return attr.count, wrapMapError(err)
|
||||
}
|
||||
|
||||
func wrapObjError(err error) error {
|
||||
if err == nil {
|
||||
_ = m.Close()
|
||||
return nil
|
||||
}
|
||||
if errors.Is(err, unix.ENOENT) {
|
||||
return fmt.Errorf("%w", ErrNotExist)
|
||||
}
|
||||
})
|
||||
|
||||
return errors.New(err.Error())
|
||||
var haveInnerMaps = internal.FeatureTest("inner maps", "5.10", func() error {
|
||||
// This checks BPF_F_INNER_MAP, which appeared in 5.10.
|
||||
m, err := sys.MapCreate(&sys.MapCreateAttr{
|
||||
MapType: sys.MapType(Array),
|
||||
KeySize: 4,
|
||||
ValueSize: 4,
|
||||
MaxEntries: 1,
|
||||
MapFlags: unix.BPF_F_INNER_MAP,
|
||||
})
|
||||
if err != nil {
|
||||
return internal.ErrNotSupported
|
||||
}
|
||||
_ = m.Close()
|
||||
return nil
|
||||
})
|
||||
|
||||
var haveNoPreallocMaps = internal.FeatureTest("prealloc maps", "4.6", func() error {
|
||||
// This checks BPF_F_NO_PREALLOC, which appeared in 4.6.
|
||||
m, err := sys.MapCreate(&sys.MapCreateAttr{
|
||||
MapType: sys.MapType(Hash),
|
||||
KeySize: 4,
|
||||
ValueSize: 4,
|
||||
MaxEntries: 1,
|
||||
MapFlags: unix.BPF_F_NO_PREALLOC,
|
||||
})
|
||||
if err != nil {
|
||||
return internal.ErrNotSupported
|
||||
}
|
||||
_ = m.Close()
|
||||
return nil
|
||||
})
|
||||
|
||||
func wrapMapError(err error) error {
|
||||
if err == nil {
|
||||
|
@ -372,60 +136,34 @@ func wrapMapError(err error) error {
|
|||
}
|
||||
|
||||
if errors.Is(err, unix.ENOENT) {
|
||||
return ErrKeyNotExist
|
||||
return sys.Error(ErrKeyNotExist, unix.ENOENT)
|
||||
}
|
||||
|
||||
if errors.Is(err, unix.EEXIST) {
|
||||
return ErrKeyExist
|
||||
return sys.Error(ErrKeyExist, unix.EEXIST)
|
||||
}
|
||||
|
||||
if errors.Is(err, unix.ENOTSUPP) {
|
||||
return ErrNotSupported
|
||||
return sys.Error(ErrNotSupported, unix.ENOTSUPP)
|
||||
}
|
||||
|
||||
return errors.New(err.Error())
|
||||
if errors.Is(err, unix.E2BIG) {
|
||||
return fmt.Errorf("key too big for map: %w", err)
|
||||
}
|
||||
|
||||
func bpfMapFreeze(m *internal.FD) error {
|
||||
fd, err := m.Value()
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
attr := bpfMapFreezeAttr{
|
||||
mapFd: fd,
|
||||
}
|
||||
_, err = internal.BPF(internal.BPF_MAP_FREEZE, unsafe.Pointer(&attr), unsafe.Sizeof(attr))
|
||||
return err
|
||||
}
|
||||
|
||||
func bpfGetProgInfoByFD(fd *internal.FD) (*bpfProgInfo, error) {
|
||||
var info bpfProgInfo
|
||||
if err := internal.BPFObjGetInfoByFD(fd, unsafe.Pointer(&info), unsafe.Sizeof(info)); err != nil {
|
||||
return nil, fmt.Errorf("can't get program info: %w", err)
|
||||
}
|
||||
return &info, nil
|
||||
}
|
||||
|
||||
func bpfGetMapInfoByFD(fd *internal.FD) (*bpfMapInfo, error) {
|
||||
var info bpfMapInfo
|
||||
err := internal.BPFObjGetInfoByFD(fd, unsafe.Pointer(&info), unsafe.Sizeof(info))
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("can't get map info: %w", err)
|
||||
}
|
||||
return &info, nil
|
||||
}
|
||||
|
||||
var haveObjName = internal.FeatureTest("object names", "4.15", func() error {
|
||||
attr := bpfMapCreateAttr{
|
||||
mapType: Array,
|
||||
keySize: 4,
|
||||
valueSize: 4,
|
||||
maxEntries: 1,
|
||||
mapName: newBPFObjName("feature_test"),
|
||||
attr := sys.MapCreateAttr{
|
||||
MapType: sys.MapType(Array),
|
||||
KeySize: 4,
|
||||
ValueSize: 4,
|
||||
MaxEntries: 1,
|
||||
MapName: sys.NewObjName("feature_test"),
|
||||
}
|
||||
|
||||
fd, err := bpfMapCreate(&attr)
|
||||
fd, err := sys.MapCreate(&attr)
|
||||
if err != nil {
|
||||
return internal.ErrNotSupported
|
||||
}
|
||||
|
@ -439,15 +177,15 @@ var objNameAllowsDot = internal.FeatureTest("dot in object names", "5.2", func()
|
|||
return err
|
||||
}
|
||||
|
||||
attr := bpfMapCreateAttr{
|
||||
mapType: Array,
|
||||
keySize: 4,
|
||||
valueSize: 4,
|
||||
maxEntries: 1,
|
||||
mapName: newBPFObjName(".test"),
|
||||
attr := sys.MapCreateAttr{
|
||||
MapType: sys.MapType(Array),
|
||||
KeySize: 4,
|
||||
ValueSize: 4,
|
||||
MaxEntries: 1,
|
||||
MapName: sys.NewObjName(".test"),
|
||||
}
|
||||
|
||||
fd, err := bpfMapCreate(&attr)
|
||||
fd, err := sys.MapCreate(&attr)
|
||||
if err != nil {
|
||||
return internal.ErrNotSupported
|
||||
}
|
||||
|
@ -458,34 +196,69 @@ var objNameAllowsDot = internal.FeatureTest("dot in object names", "5.2", func()
|
|||
|
||||
var haveBatchAPI = internal.FeatureTest("map batch api", "5.6", func() error {
|
||||
var maxEntries uint32 = 2
|
||||
attr := bpfMapCreateAttr{
|
||||
mapType: Hash,
|
||||
keySize: 4,
|
||||
valueSize: 4,
|
||||
maxEntries: maxEntries,
|
||||
attr := sys.MapCreateAttr{
|
||||
MapType: sys.MapType(Hash),
|
||||
KeySize: 4,
|
||||
ValueSize: 4,
|
||||
MaxEntries: maxEntries,
|
||||
}
|
||||
|
||||
fd, err := bpfMapCreate(&attr)
|
||||
fd, err := sys.MapCreate(&attr)
|
||||
if err != nil {
|
||||
return internal.ErrNotSupported
|
||||
}
|
||||
defer fd.Close()
|
||||
|
||||
keys := []uint32{1, 2}
|
||||
values := []uint32{3, 4}
|
||||
kp, _ := marshalPtr(keys, 8)
|
||||
vp, _ := marshalPtr(values, 8)
|
||||
nilPtr := internal.NewPointer(nil)
|
||||
_, err = bpfMapBatch(internal.BPF_MAP_UPDATE_BATCH, fd, nilPtr, nilPtr, kp, vp, maxEntries, nil)
|
||||
|
||||
err = sys.MapUpdateBatch(&sys.MapUpdateBatchAttr{
|
||||
MapFd: fd.Uint(),
|
||||
Keys: kp,
|
||||
Values: vp,
|
||||
Count: maxEntries,
|
||||
})
|
||||
if err != nil {
|
||||
return internal.ErrNotSupported
|
||||
}
|
||||
return nil
|
||||
})
|
||||
|
||||
func bpfObjGetFDByID(cmd internal.BPFCmd, id uint32) (*internal.FD, error) {
|
||||
attr := bpfGetFDByIDAttr{
|
||||
id: id,
|
||||
var haveProbeReadKernel = internal.FeatureTest("bpf_probe_read_kernel", "5.5", func() error {
|
||||
insns := asm.Instructions{
|
||||
asm.Mov.Reg(asm.R1, asm.R10),
|
||||
asm.Add.Imm(asm.R1, -8),
|
||||
asm.Mov.Imm(asm.R2, 8),
|
||||
asm.Mov.Imm(asm.R3, 0),
|
||||
asm.FnProbeReadKernel.Call(),
|
||||
asm.Return(),
|
||||
}
|
||||
ptr, err := internal.BPF(cmd, unsafe.Pointer(&attr), unsafe.Sizeof(attr))
|
||||
return internal.NewFD(uint32(ptr)), wrapObjError(err)
|
||||
|
||||
fd, err := progLoad(insns, Kprobe, "GPL")
|
||||
if err != nil {
|
||||
return internal.ErrNotSupported
|
||||
}
|
||||
_ = fd.Close()
|
||||
return nil
|
||||
})
|
||||
|
||||
var haveBPFToBPFCalls = internal.FeatureTest("bpf2bpf calls", "4.16", func() error {
|
||||
insns := asm.Instructions{
|
||||
asm.Call.Label("prog2").WithSymbol("prog1"),
|
||||
asm.Return(),
|
||||
asm.Mov.Imm(asm.R0, 0).WithSymbol("prog2"),
|
||||
asm.Return(),
|
||||
}
|
||||
|
||||
fd, err := progLoad(insns, SocketFilter, "MIT")
|
||||
if errors.Is(err, unix.EINVAL) {
|
||||
return internal.ErrNotSupported
|
||||
}
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
_ = fd.Close()
|
||||
return nil
|
||||
})
|
||||
|
|
|
@ -1,11 +1,20 @@
|
|||
package ebpf
|
||||
|
||||
//go:generate stringer -output types_string.go -type=MapType,ProgramType,AttachType,PinType
|
||||
import (
|
||||
"github.com/cilium/ebpf/internal/unix"
|
||||
)
|
||||
|
||||
//go:generate stringer -output types_string.go -type=MapType,ProgramType,PinType
|
||||
|
||||
// MapType indicates the type map structure
|
||||
// that will be initialized in the kernel.
|
||||
type MapType uint32
|
||||
|
||||
// Max returns the latest supported MapType.
|
||||
func (MapType) Max() MapType {
|
||||
return maxMapType - 1
|
||||
}
|
||||
|
||||
// All the various map types that can be created
|
||||
const (
|
||||
UnspecifiedMap MapType = iota
|
||||
|
@ -81,11 +90,22 @@ const (
|
|||
SkStorage
|
||||
// DevMapHash - Hash-based indexing scheme for references to network devices.
|
||||
DevMapHash
|
||||
// StructOpsMap - This map holds a kernel struct with its function pointer implemented in a BPF
|
||||
// program.
|
||||
StructOpsMap
|
||||
// RingBuf - Similar to PerfEventArray, but shared across all CPUs.
|
||||
RingBuf
|
||||
// InodeStorage - Specialized local storage map for inodes.
|
||||
InodeStorage
|
||||
// TaskStorage - Specialized local storage map for task_struct.
|
||||
TaskStorage
|
||||
// maxMapType - Bound enum of MapTypes, has to be last in enum.
|
||||
maxMapType
|
||||
)
|
||||
|
||||
// hasPerCPUValue returns true if the Map stores a value per CPU.
|
||||
func (mt MapType) hasPerCPUValue() bool {
|
||||
return mt == PerCPUHash || mt == PerCPUArray || mt == LRUCPUHash
|
||||
return mt == PerCPUHash || mt == PerCPUArray || mt == LRUCPUHash || mt == PerCPUCGroupStorage
|
||||
}
|
||||
|
||||
// canStoreMap returns true if the map type accepts a map fd
|
||||
|
@ -100,9 +120,25 @@ func (mt MapType) canStoreProgram() bool {
|
|||
return mt == ProgramArray
|
||||
}
|
||||
|
||||
// hasBTF returns true if the map type supports BTF key/value metadata.
|
||||
func (mt MapType) hasBTF() bool {
|
||||
switch mt {
|
||||
case PerfEventArray, CGroupArray, StackTrace, ArrayOfMaps, HashOfMaps, DevMap,
|
||||
DevMapHash, CPUMap, XSKMap, SockMap, SockHash, Queue, Stack, RingBuf:
|
||||
return false
|
||||
default:
|
||||
return true
|
||||
}
|
||||
}
|
||||
|
||||
// ProgramType of the eBPF program
|
||||
type ProgramType uint32
|
||||
|
||||
// Max return the latest supported ProgramType.
|
||||
func (ProgramType) Max() ProgramType {
|
||||
return maxProgramType - 1
|
||||
}
|
||||
|
||||
// eBPF program types
|
||||
const (
|
||||
UnspecifiedProgram ProgramType = iota
|
||||
|
@ -136,6 +172,8 @@ const (
|
|||
Extension
|
||||
LSM
|
||||
SkLookup
|
||||
Syscall
|
||||
maxProgramType
|
||||
)
|
||||
|
||||
// AttachType of the eBPF program, needed to differentiate allowed context accesses in
|
||||
|
@ -143,6 +181,8 @@ const (
|
|||
// Will cause invalid argument (EINVAL) at program load time if set incorrectly.
|
||||
type AttachType uint32
|
||||
|
||||
//go:generate stringer -type AttachType -trimprefix Attach
|
||||
|
||||
// AttachNone is an alias for AttachCGroupInetIngress for readability reasons.
|
||||
const AttachNone AttachType = 0
|
||||
|
||||
|
@ -185,6 +225,10 @@ const (
|
|||
AttachXDPCPUMap
|
||||
AttachSkLookup
|
||||
AttachXDP
|
||||
AttachSkSKBVerdict
|
||||
AttachSkReuseportSelect
|
||||
AttachSkReuseportSelectOrMigrate
|
||||
AttachPerfEvent
|
||||
)
|
||||
|
||||
// AttachFlags of the eBPF program used in BPF_PROG_ATTACH command
|
||||
|
@ -202,6 +246,33 @@ const (
|
|||
PinByName
|
||||
)
|
||||
|
||||
// LoadPinOptions control how a pinned object is loaded.
|
||||
type LoadPinOptions struct {
|
||||
// Request a read-only or write-only object. The default is a read-write
|
||||
// object. Only one of the flags may be set.
|
||||
ReadOnly bool
|
||||
WriteOnly bool
|
||||
|
||||
// Raw flags for the syscall. Other fields of this struct take precedence.
|
||||
Flags uint32
|
||||
}
|
||||
|
||||
// Marshal returns a value suitable for BPF_OBJ_GET syscall file_flags parameter.
|
||||
func (lpo *LoadPinOptions) Marshal() uint32 {
|
||||
if lpo == nil {
|
||||
return 0
|
||||
}
|
||||
|
||||
flags := lpo.Flags
|
||||
if lpo.ReadOnly {
|
||||
flags |= unix.BPF_F_RDONLY
|
||||
}
|
||||
if lpo.WriteOnly {
|
||||
flags |= unix.BPF_F_WRONLY
|
||||
}
|
||||
return flags
|
||||
}
|
||||
|
||||
// BatchOptions batch map operations options
|
||||
//
|
||||
// Mirrors libbpf struct bpf_map_batch_opts
|
||||
|
|
|
@ -1,4 +1,4 @@
|
|||
// Code generated by "stringer -output types_string.go -type=MapType,ProgramType,AttachType,PinType"; DO NOT EDIT.
|
||||
// Code generated by "stringer -output types_string.go -type=MapType,ProgramType,PinType"; DO NOT EDIT.
|
||||
|
||||
package ebpf
|
||||
|
||||
|
@ -34,11 +34,16 @@ func _() {
|
|||
_ = x[Stack-23]
|
||||
_ = x[SkStorage-24]
|
||||
_ = x[DevMapHash-25]
|
||||
_ = x[StructOpsMap-26]
|
||||
_ = x[RingBuf-27]
|
||||
_ = x[InodeStorage-28]
|
||||
_ = x[TaskStorage-29]
|
||||
_ = x[maxMapType-30]
|
||||
}
|
||||
|
||||
const _MapType_name = "UnspecifiedMapHashArrayProgramArrayPerfEventArrayPerCPUHashPerCPUArrayStackTraceCGroupArrayLRUHashLRUCPUHashLPMTrieArrayOfMapsHashOfMapsDevMapSockMapCPUMapXSKMapSockHashCGroupStorageReusePortSockArrayPerCPUCGroupStorageQueueStackSkStorageDevMapHash"
|
||||
const _MapType_name = "UnspecifiedMapHashArrayProgramArrayPerfEventArrayPerCPUHashPerCPUArrayStackTraceCGroupArrayLRUHashLRUCPUHashLPMTrieArrayOfMapsHashOfMapsDevMapSockMapCPUMapXSKMapSockHashCGroupStorageReusePortSockArrayPerCPUCGroupStorageQueueStackSkStorageDevMapHashStructOpsMapRingBufInodeStorageTaskStoragemaxMapType"
|
||||
|
||||
var _MapType_index = [...]uint8{0, 14, 18, 23, 35, 49, 59, 70, 80, 91, 98, 108, 115, 126, 136, 142, 149, 155, 161, 169, 182, 200, 219, 224, 229, 238, 248}
|
||||
var _MapType_index = [...]uint16{0, 14, 18, 23, 35, 49, 59, 70, 80, 91, 98, 108, 115, 126, 136, 142, 149, 155, 161, 169, 182, 200, 219, 224, 229, 238, 248, 260, 267, 279, 290, 300}
|
||||
|
||||
func (i MapType) String() string {
|
||||
if i >= MapType(len(_MapType_index)-1) {
|
||||
|
@ -81,11 +86,13 @@ func _() {
|
|||
_ = x[Extension-28]
|
||||
_ = x[LSM-29]
|
||||
_ = x[SkLookup-30]
|
||||
_ = x[Syscall-31]
|
||||
_ = x[maxProgramType-32]
|
||||
}
|
||||
|
||||
const _ProgramType_name = "UnspecifiedProgramSocketFilterKprobeSchedCLSSchedACTTracePointXDPPerfEventCGroupSKBCGroupSockLWTInLWTOutLWTXmitSockOpsSkSKBCGroupDeviceSkMsgRawTracepointCGroupSockAddrLWTSeg6LocalLircMode2SkReuseportFlowDissectorCGroupSysctlRawTracepointWritableCGroupSockoptTracingStructOpsExtensionLSMSkLookup"
|
||||
const _ProgramType_name = "UnspecifiedProgramSocketFilterKprobeSchedCLSSchedACTTracePointXDPPerfEventCGroupSKBCGroupSockLWTInLWTOutLWTXmitSockOpsSkSKBCGroupDeviceSkMsgRawTracepointCGroupSockAddrLWTSeg6LocalLircMode2SkReuseportFlowDissectorCGroupSysctlRawTracepointWritableCGroupSockoptTracingStructOpsExtensionLSMSkLookupSyscallmaxProgramType"
|
||||
|
||||
var _ProgramType_index = [...]uint16{0, 18, 30, 36, 44, 52, 62, 65, 74, 83, 93, 98, 104, 111, 118, 123, 135, 140, 153, 167, 179, 188, 199, 212, 224, 245, 258, 265, 274, 283, 286, 294}
|
||||
var _ProgramType_index = [...]uint16{0, 18, 30, 36, 44, 52, 62, 65, 74, 83, 93, 98, 104, 111, 118, 123, 135, 140, 153, 167, 179, 188, 199, 212, 224, 245, 258, 265, 274, 283, 286, 294, 301, 315}
|
||||
|
||||
func (i ProgramType) String() string {
|
||||
if i >= ProgramType(len(_ProgramType_index)-1) {
|
||||
|
@ -93,61 +100,6 @@ func (i ProgramType) String() string {
|
|||
}
|
||||
return _ProgramType_name[_ProgramType_index[i]:_ProgramType_index[i+1]]
|
||||
}
|
||||
func _() {
|
||||
// An "invalid array index" compiler error signifies that the constant values have changed.
|
||||
// Re-run the stringer command to generate them again.
|
||||
var x [1]struct{}
|
||||
_ = x[AttachNone-0]
|
||||
_ = x[AttachCGroupInetIngress-0]
|
||||
_ = x[AttachCGroupInetEgress-1]
|
||||
_ = x[AttachCGroupInetSockCreate-2]
|
||||
_ = x[AttachCGroupSockOps-3]
|
||||
_ = x[AttachSkSKBStreamParser-4]
|
||||
_ = x[AttachSkSKBStreamVerdict-5]
|
||||
_ = x[AttachCGroupDevice-6]
|
||||
_ = x[AttachSkMsgVerdict-7]
|
||||
_ = x[AttachCGroupInet4Bind-8]
|
||||
_ = x[AttachCGroupInet6Bind-9]
|
||||
_ = x[AttachCGroupInet4Connect-10]
|
||||
_ = x[AttachCGroupInet6Connect-11]
|
||||
_ = x[AttachCGroupInet4PostBind-12]
|
||||
_ = x[AttachCGroupInet6PostBind-13]
|
||||
_ = x[AttachCGroupUDP4Sendmsg-14]
|
||||
_ = x[AttachCGroupUDP6Sendmsg-15]
|
||||
_ = x[AttachLircMode2-16]
|
||||
_ = x[AttachFlowDissector-17]
|
||||
_ = x[AttachCGroupSysctl-18]
|
||||
_ = x[AttachCGroupUDP4Recvmsg-19]
|
||||
_ = x[AttachCGroupUDP6Recvmsg-20]
|
||||
_ = x[AttachCGroupGetsockopt-21]
|
||||
_ = x[AttachCGroupSetsockopt-22]
|
||||
_ = x[AttachTraceRawTp-23]
|
||||
_ = x[AttachTraceFEntry-24]
|
||||
_ = x[AttachTraceFExit-25]
|
||||
_ = x[AttachModifyReturn-26]
|
||||
_ = x[AttachLSMMac-27]
|
||||
_ = x[AttachTraceIter-28]
|
||||
_ = x[AttachCgroupInet4GetPeername-29]
|
||||
_ = x[AttachCgroupInet6GetPeername-30]
|
||||
_ = x[AttachCgroupInet4GetSockname-31]
|
||||
_ = x[AttachCgroupInet6GetSockname-32]
|
||||
_ = x[AttachXDPDevMap-33]
|
||||
_ = x[AttachCgroupInetSockRelease-34]
|
||||
_ = x[AttachXDPCPUMap-35]
|
||||
_ = x[AttachSkLookup-36]
|
||||
_ = x[AttachXDP-37]
|
||||
}
|
||||
|
||||
const _AttachType_name = "AttachNoneAttachCGroupInetEgressAttachCGroupInetSockCreateAttachCGroupSockOpsAttachSkSKBStreamParserAttachSkSKBStreamVerdictAttachCGroupDeviceAttachSkMsgVerdictAttachCGroupInet4BindAttachCGroupInet6BindAttachCGroupInet4ConnectAttachCGroupInet6ConnectAttachCGroupInet4PostBindAttachCGroupInet6PostBindAttachCGroupUDP4SendmsgAttachCGroupUDP6SendmsgAttachLircMode2AttachFlowDissectorAttachCGroupSysctlAttachCGroupUDP4RecvmsgAttachCGroupUDP6RecvmsgAttachCGroupGetsockoptAttachCGroupSetsockoptAttachTraceRawTpAttachTraceFEntryAttachTraceFExitAttachModifyReturnAttachLSMMacAttachTraceIterAttachCgroupInet4GetPeernameAttachCgroupInet6GetPeernameAttachCgroupInet4GetSocknameAttachCgroupInet6GetSocknameAttachXDPDevMapAttachCgroupInetSockReleaseAttachXDPCPUMapAttachSkLookupAttachXDP"
|
||||
|
||||
var _AttachType_index = [...]uint16{0, 10, 32, 58, 77, 100, 124, 142, 160, 181, 202, 226, 250, 275, 300, 323, 346, 361, 380, 398, 421, 444, 466, 488, 504, 521, 537, 555, 567, 582, 610, 638, 666, 694, 709, 736, 751, 765, 774}
|
||||
|
||||
func (i AttachType) String() string {
|
||||
if i >= AttachType(len(_AttachType_index)-1) {
|
||||
return "AttachType(" + strconv.FormatInt(int64(i), 10) + ")"
|
||||
}
|
||||
return _AttachType_name[_AttachType_index[i]:_AttachType_index[i+1]]
|
||||
}
|
||||
func _() {
|
||||
// An "invalid array index" compiler error signifies that the constant values have changed.
|
||||
// Re-run the stringer command to generate them again.
|
||||
|
|
|
@ -1,46 +0,0 @@
|
|||
version = "unstable"
|
||||
generator = "gogoctrd"
|
||||
plugins = ["grpc"]
|
||||
|
||||
# Control protoc include paths. Below are usually some good defaults, but feel
|
||||
# free to try it without them if it works for your project.
|
||||
[includes]
|
||||
# Include paths that will be added before all others. Typically, you want to
|
||||
# treat the root of the project as an include, but this may not be necessary.
|
||||
# before = ["."]
|
||||
|
||||
# Paths that should be treated as include roots in relation to the vendor
|
||||
# directory. These will be calculated with the vendor directory nearest the
|
||||
# target package.
|
||||
# vendored = ["github.com/gogo/protobuf"]
|
||||
packages = ["github.com/gogo/protobuf"]
|
||||
|
||||
# Paths that will be added untouched to the end of the includes. We use
|
||||
# `/usr/local/include` to pickup the common install location of protobuf.
|
||||
# This is the default.
|
||||
after = ["/usr/local/include", "/usr/include"]
|
||||
|
||||
# This section maps protobuf imports to Go packages. These will become
|
||||
# `-M` directives in the call to the go protobuf generator.
|
||||
[packages]
|
||||
"gogoproto/gogo.proto" = "github.com/gogo/protobuf/gogoproto"
|
||||
"google/protobuf/any.proto" = "github.com/gogo/protobuf/types"
|
||||
"google/protobuf/descriptor.proto" = "github.com/gogo/protobuf/protoc-gen-gogo/descriptor"
|
||||
"google/protobuf/field_mask.proto" = "github.com/gogo/protobuf/types"
|
||||
"google/protobuf/timestamp.proto" = "github.com/gogo/protobuf/types"
|
||||
|
||||
# Aggregrate the API descriptors to lock down API changes.
|
||||
[[descriptors]]
|
||||
prefix = "github.com/containerd/cgroups/stats/v1"
|
||||
target = "stats/v1/metrics.pb.txt"
|
||||
ignore_files = [
|
||||
"google/protobuf/descriptor.proto",
|
||||
"gogoproto/gogo.proto"
|
||||
]
|
||||
[[descriptors]]
|
||||
prefix = "github.com/containerd/cgroups/v2/stats"
|
||||
target = "v2/stats/metrics.pb.txt"
|
||||
ignore_files = [
|
||||
"google/protobuf/descriptor.proto",
|
||||
"gogoproto/gogo.proto"
|
||||
]
|
|
@ -1,46 +0,0 @@
|
|||
# -*- mode: ruby -*-
|
||||
# vi: set ft=ruby :
|
||||
|
||||
Vagrant.configure("2") do |config|
|
||||
# Fedora box is used for testing cgroup v2 support
|
||||
config.vm.box = "fedora/35-cloud-base"
|
||||
config.vm.provider :virtualbox do |v|
|
||||
v.memory = 4096
|
||||
v.cpus = 2
|
||||
end
|
||||
config.vm.provider :libvirt do |v|
|
||||
v.memory = 4096
|
||||
v.cpus = 2
|
||||
end
|
||||
config.vm.provision "shell", inline: <<-SHELL
|
||||
set -eux -o pipefail
|
||||
# configuration
|
||||
GO_VERSION="1.17.7"
|
||||
|
||||
# install gcc and Golang
|
||||
dnf -y install gcc
|
||||
curl -fsSL "https://dl.google.com/go/go${GO_VERSION}.linux-amd64.tar.gz" | tar Cxz /usr/local
|
||||
|
||||
# setup env vars
|
||||
cat >> /etc/profile.d/sh.local <<EOF
|
||||
PATH=/usr/local/go/bin:$PATH
|
||||
GO111MODULE=on
|
||||
export PATH GO111MODULE
|
||||
EOF
|
||||
source /etc/profile.d/sh.local
|
||||
|
||||
# enter /root/go/src/github.com/containerd/cgroups
|
||||
mkdir -p /root/go/src/github.com/containerd
|
||||
ln -s /vagrant /root/go/src/github.com/containerd/cgroups
|
||||
cd /root/go/src/github.com/containerd/cgroups
|
||||
|
||||
# create /test.sh
|
||||
cat > /test.sh <<EOF
|
||||
#!/bin/bash
|
||||
set -eux -o pipefail
|
||||
cd /root/go/src/github.com/containerd/cgroups
|
||||
go test -v ./...
|
||||
EOF
|
||||
chmod +x /test.sh
|
||||
SHELL
|
||||
end
|
File diff suppressed because it is too large
Load Diff
File diff suppressed because it is too large
Load Diff
|
@ -22,3 +22,5 @@ cgutil:
|
|||
|
||||
proto:
|
||||
protobuild --quiet ${PACKAGES}
|
||||
# Keep them Go-idiomatic and backward-compatible with the gogo/protobuf era.
|
||||
go-fix-acronym -w -a '(Cpu|Tcp|Rss)' $(shell find cgroup1/stats/ cgroup2/stats/ -name '*.pb.go')
|
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Reference in New Issue