diff options
Diffstat (limited to 'vendor/golang.org/x/crypto/ssh/client_auth.go')
| -rw-r--r-- | vendor/golang.org/x/crypto/ssh/client_auth.go | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/vendor/golang.org/x/crypto/ssh/client_auth.go b/vendor/golang.org/x/crypto/ssh/client_auth.go index 5c3bc2572..34bf089d0 100644 --- a/vendor/golang.org/x/crypto/ssh/client_auth.go +++ b/vendor/golang.org/x/crypto/ssh/client_auth.go @@ -307,7 +307,10 @@ func (cb publicKeyCallback) auth(session []byte, user string, c packetConn, rand } var methods []string var errSigAlgo error - for _, signer := range signers { + + origSignersLen := len(signers) + for idx := 0; idx < len(signers); idx++ { + signer := signers[idx] pub := signer.PublicKey() as, algo, err := pickSignatureAlgorithm(signer, extensions) if err != nil && errSigAlgo == nil { @@ -321,6 +324,21 @@ func (cb publicKeyCallback) auth(session []byte, user string, c packetConn, rand if err != nil { return authFailure, nil, err } + // OpenSSH 7.2-7.7 advertises support for rsa-sha2-256 and rsa-sha2-512 + // in the "server-sig-algs" extension but doesn't support these + // algorithms for certificate authentication, so if the server rejects + // the key try to use the obtained algorithm as if "server-sig-algs" had + // not been implemented if supported from the algorithm signer. + if !ok && idx < origSignersLen && isRSACert(algo) && algo != CertAlgoRSAv01 { + if contains(as.Algorithms(), KeyAlgoRSA) { + // We retry using the compat algorithm after all signers have + // been tried normally. + signers = append(signers, &multiAlgorithmSigner{ + AlgorithmSigner: as, + supportedAlgorithms: []string{KeyAlgoRSA}, + }) + } + } if !ok { continue } |