diff options
Diffstat (limited to 'ssh')
| -rw-r--r-- | ssh/doc.go | 1 | ||||
| -rw-r--r-- | ssh/handshake.go | 10 | ||||
| -rw-r--r-- | ssh/messages.go | 14 | ||||
| -rw-r--r-- | ssh/mux.go | 6 |
4 files changed, 28 insertions, 3 deletions
@@ -13,6 +13,7 @@ others. References: + [PROTOCOL]: https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/PROTOCOL?rev=HEAD [PROTOCOL.certkeys]: http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/PROTOCOL.certkeys?rev=HEAD [SSH-PARAMETERS]: http://www.iana.org/assignments/ssh-parameters/ssh-parameters.xml#ssh-parameters-1 diff --git a/ssh/handshake.go b/ssh/handshake.go index b95b112..70a7369 100644 --- a/ssh/handshake.go +++ b/ssh/handshake.go @@ -647,16 +647,20 @@ func (t *handshakeTransport) enterKeyExchange(otherInitPacket []byte) error { // On the server side, after the first SSH_MSG_NEWKEYS, send a SSH_MSG_EXT_INFO // message with the server-sig-algs extension if the client supports it. See - // RFC 8308, Sections 2.4 and 3.1. + // RFC 8308, Sections 2.4 and 3.1, and [PROTOCOL], Section 1.9. if !isClient && firstKeyExchange && contains(clientInit.KexAlgos, "ext-info-c") { extInfo := &extInfoMsg{ - NumExtensions: 1, - Payload: make([]byte, 0, 4+15+4+len(supportedPubKeyAuthAlgosList)), + NumExtensions: 2, + Payload: make([]byte, 0, 4+15+4+len(supportedPubKeyAuthAlgosList)+4+16+4+1), } extInfo.Payload = appendInt(extInfo.Payload, len("server-sig-algs")) extInfo.Payload = append(extInfo.Payload, "server-sig-algs"...) extInfo.Payload = appendInt(extInfo.Payload, len(supportedPubKeyAuthAlgosList)) extInfo.Payload = append(extInfo.Payload, supportedPubKeyAuthAlgosList...) + extInfo.Payload = appendInt(extInfo.Payload, len("ping@openssh.com")) + extInfo.Payload = append(extInfo.Payload, "ping@openssh.com"...) + extInfo.Payload = appendInt(extInfo.Payload, 1) + extInfo.Payload = append(extInfo.Payload, "0"...) if err := t.conn.writePacket(Marshal(extInfo)); err != nil { return err } diff --git a/ssh/messages.go b/ssh/messages.go index 922032d..b55f860 100644 --- a/ssh/messages.go +++ b/ssh/messages.go @@ -349,6 +349,20 @@ type userAuthGSSAPIError struct { LanguageTag string } +// Transport layer OpenSSH extension. See [PROTOCOL], section 1.9 +const msgPing = 192 + +type pingMsg struct { + Data string `sshtype:"192"` +} + +// Transport layer OpenSSH extension. See [PROTOCOL], section 1.9 +const msgPong = 193 + +type pongMsg struct { + Data string `sshtype:"193"` +} + // typeTags returns the possible type bytes for the given reflect.Type, which // should be a struct. The possible values are separated by a '|' character. func typeTags(structType reflect.Type) (tags []byte) { @@ -231,6 +231,12 @@ func (m *mux) onePacket() error { return m.handleChannelOpen(packet) case msgGlobalRequest, msgRequestSuccess, msgRequestFailure: return m.handleGlobalPacket(packet) + case msgPing: + var msg pingMsg + if err := Unmarshal(packet, &msg); err != nil { + return fmt.Errorf("failed to unmarshal ping@openssh.com message: %w", err) + } + return m.sendMessage(pongMsg(msg)) } // assume a channel packet. |