102 lines
3.2 KiB
Markdown
102 lines
3.2 KiB
Markdown
|
# httpsig
|
||
|
|
|
||
|
|
**THIS IS A FORK OF https://github.com/go-fed/httpsig, WHICH WAS NO LONGER MAINTAINED. THANK YOU TO [cjslep](https://github.com/cjslep) FOR ALL YOUR HARD WORK!**
|
||
|
|
|
||
|
|
> HTTP Signatures made simple
|
||
|
|
|
||
|
|
`go get github.com/superseriousbusiness/httpsig`
|
||
|
|
|
||
|
|
Implementation of [HTTP Signatures](https://tools.ietf.org/html/draft-cavage-http-signatures).
|
||
|
|
|
||
|
|
Supports many different combinations of MAC, HMAC signing of hash, or RSA
|
||
|
|
signing of hash schemes. Its goals are:
|
||
|
|
|
||
|
|
* Have a very simple interface for signing and validating
|
||
|
|
* Support a variety of signing algorithms and combinations
|
||
|
|
* Support setting either headers (`Authorization` or `Signature`)
|
||
|
|
* Remaining flexible with headers included in the signing string
|
||
|
|
* Support both HTTP requests and responses
|
||
|
|
* Explicitly not support known-cryptographically weak algorithms
|
||
|
|
* Support automatic signing and validating Digest headers
|
||
|
|
|
||
|
|
## How to use
|
||
|
|
|
||
|
|
`import "github.com/superseriousbusiness/httpsig"`
|
||
|
|
|
||
|
|
### Signing
|
||
|
|
|
||
|
|
Signing a request or response requires creating a new `Signer` and using it:
|
||
|
|
|
||
|
|
```go
|
||
|
|
func sign(privateKey crypto.PrivateKey, pubKeyId string, r *http.Request) error {
|
||
|
|
prefs := []httpsig.Algorithm{httpsig.RSA_SHA512, httpsig.RSA_SHA256}
|
||
|
|
digestAlgorithm := DigestSha256
|
||
|
|
// The "Date" and "Digest" headers must already be set on r, as well as r.URL.
|
||
|
|
headersToSign := []string{httpsig.RequestTarget, "date", "digest"}
|
||
|
|
signer, chosenAlgo, err := httpsig.NewSigner(prefs, digestAlgorithm, headersToSign, httpsig.Signature)
|
||
|
|
if err != nil {
|
||
|
|
return err
|
||
|
|
}
|
||
|
|
// To sign the digest, we need to give the signer a copy of the body...
|
||
|
|
// ...but it is optional, no digest will be signed if given "nil"
|
||
|
|
body := ...
|
||
|
|
// If r were a http.ResponseWriter, call SignResponse instead.
|
||
|
|
return signer.SignRequest(privateKey, pubKeyId, r, body)
|
||
|
|
}
|
||
|
|
```
|
||
|
|
|
||
|
|
`Signer`s are not safe for concurrent use by goroutines, so be sure to guard
|
||
|
|
access:
|
||
|
|
|
||
|
|
```go
|
||
|
|
type server struct {
|
||
|
|
signer httpsig.Signer
|
||
|
|
mu *sync.Mutex
|
||
|
|
}
|
||
|
|
|
||
|
|
func (s *server) handlerFunc(w http.ResponseWriter, r *http.Request) {
|
||
|
|
privateKey := ...
|
||
|
|
pubKeyId := ...
|
||
|
|
// Set headers and such on w
|
||
|
|
s.mu.Lock()
|
||
|
|
defer s.mu.Unlock()
|
||
|
|
// To sign the digest, we need to give the signer a copy of the response body...
|
||
|
|
// ...but it is optional, no digest will be signed if given "nil"
|
||
|
|
body := ...
|
||
|
|
err := s.signer.SignResponse(privateKey, pubKeyId, w, body)
|
||
|
|
if err != nil {
|
||
|
|
...
|
||
|
|
}
|
||
|
|
...
|
||
|
|
}
|
||
|
|
```
|
||
|
|
|
||
|
|
The `pubKeyId` will be used at verification time.
|
||
|
|
|
||
|
|
### Verifying
|
||
|
|
|
||
|
|
Verifying requires an application to use the `pubKeyId` to both retrieve the key
|
||
|
|
needed for verification as well as determine the algorithm to use. Use a
|
||
|
|
`Verifier`:
|
||
|
|
|
||
|
|
```go
|
||
|
|
func verify(r *http.Request) error {
|
||
|
|
verifier, err := httpsig.NewVerifier(r)
|
||
|
|
if err != nil {
|
||
|
|
return err
|
||
|
|
}
|
||
|
|
pubKeyId := verifier.KeyId()
|
||
|
|
var algo httpsig.Algorithm = ...
|
||
|
|
var pubKey crypto.PublicKey = ...
|
||
|
|
// The verifier will verify the Digest in addition to the HTTP signature
|
||
|
|
return verifier.Verify(pubKey, algo)
|
||
|
|
}
|
||
|
|
```
|
||
|
|
|
||
|
|
`Verifier`s are not safe for concurrent use by goroutines, but since they are
|
||
|
|
constructed on a per-request or per-response basis it should not be a common
|
||
|
|
restriction.
|
||
|
|
|
||
|
|
[License-Image]: https://img.shields.io/github/license/go-fed/httpsig?color=blue
|
||
|
|
[License-Url]: https://opensource.org/licenses/BSD-3-Clause
|