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gotosocial/vendor/github.com/jackc/pgconn/krb5.go

100 lines
2.3 KiB
Go

package pgconn
import (
"errors"
"fmt"
"github.com/jackc/pgproto3/v2"
)
// NewGSSFunc creates a GSS authentication provider, for use with
// RegisterGSSProvider.
type NewGSSFunc func() (GSS, error)
var newGSS NewGSSFunc
// RegisterGSSProvider registers a GSS authentication provider. For example, if
// you need to use Kerberos to authenticate with your server, add this to your
// main package:
//
// import "github.com/otan/gopgkrb5"
//
// func init() {
// pgconn.RegisterGSSProvider(func() (pgconn.GSS, error) { return gopgkrb5.NewGSS() })
// }
func RegisterGSSProvider(newGSSArg NewGSSFunc) {
newGSS = newGSSArg
}
// GSS provides GSSAPI authentication (e.g., Kerberos).
type GSS interface {
GetInitToken(host string, service string) ([]byte, error)
GetInitTokenFromSPN(spn string) ([]byte, error)
Continue(inToken []byte) (done bool, outToken []byte, err error)
}
func (c *PgConn) gssAuth() error {
if newGSS == nil {
return errors.New("kerberos error: no GSSAPI provider registered, see https://github.com/otan/gopgkrb5")
}
cli, err := newGSS()
if err != nil {
return err
}
var nextData []byte
if c.config.KerberosSpn != "" {
// Use the supplied SPN if provided.
nextData, err = cli.GetInitTokenFromSPN(c.config.KerberosSpn)
} else {
// Allow the kerberos service name to be overridden
service := "postgres"
if c.config.KerberosSrvName != "" {
service = c.config.KerberosSrvName
}
nextData, err = cli.GetInitToken(c.config.Host, service)
}
if err != nil {
return err
}
for {
gssResponse := &pgproto3.GSSResponse{
Data: nextData,
}
_, err = c.conn.Write(gssResponse.Encode(nil))
if err != nil {
return err
}
resp, err := c.rxGSSContinue()
if err != nil {
return err
}
var done bool
done, nextData, err = cli.Continue(resp.Data)
if err != nil {
return err
}
if done {
break
}
}
return nil
}
func (c *PgConn) rxGSSContinue() (*pgproto3.AuthenticationGSSContinue, error) {
msg, err := c.receiveMessage()
if err != nil {
return nil, err
}
switch m := msg.(type) {
case *pgproto3.AuthenticationGSSContinue:
return m, nil
case *pgproto3.ErrorResponse:
return nil, ErrorResponseToPgError(m)
}
return nil, fmt.Errorf("expected AuthenticationGSSContinue message but received unexpected message %T", msg)
}