diff options
Diffstat (limited to 'vendor/golang.org/x/crypto/ssh/handshake.go')
| -rw-r--r-- | vendor/golang.org/x/crypto/ssh/handshake.go | 69 |
1 files changed, 50 insertions, 19 deletions
diff --git a/vendor/golang.org/x/crypto/ssh/handshake.go b/vendor/golang.org/x/crypto/ssh/handshake.go index 653dc4d2c..07a1843e0 100644 --- a/vendor/golang.org/x/crypto/ssh/handshake.go +++ b/vendor/golang.org/x/crypto/ssh/handshake.go @@ -58,11 +58,13 @@ type handshakeTransport struct { incoming chan []byte readError error - mu sync.Mutex - writeError error - sentInitPacket []byte - sentInitMsg *kexInitMsg - pendingPackets [][]byte // Used when a key exchange is in progress. + mu sync.Mutex + writeError error + sentInitPacket []byte + sentInitMsg *kexInitMsg + pendingPackets [][]byte // Used when a key exchange is in progress. + writePacketsLeft uint32 + writeBytesLeft int64 // If the read loop wants to schedule a kex, it pings this // channel, and the write loop will send out a kex @@ -71,7 +73,8 @@ type handshakeTransport struct { // If the other side requests or confirms a kex, its kexInit // packet is sent here for the write loop to find it. - startKex chan *pendingKex + startKex chan *pendingKex + kexLoopDone chan struct{} // closed (with writeError non-nil) when kexLoop exits // data for host key checking hostKeyCallback HostKeyCallback @@ -86,12 +89,10 @@ type handshakeTransport struct { // Algorithms agreed in the last key exchange. algorithms *algorithms + // Counters exclusively owned by readLoop. readPacketsLeft uint32 readBytesLeft int64 - writePacketsLeft uint32 - writeBytesLeft int64 - // The session ID or nil if first kex did not complete yet. sessionID []byte } @@ -108,7 +109,8 @@ func newHandshakeTransport(conn keyingTransport, config *Config, clientVersion, clientVersion: clientVersion, incoming: make(chan []byte, chanSize), requestKex: make(chan struct{}, 1), - startKex: make(chan *pendingKex, 1), + startKex: make(chan *pendingKex), + kexLoopDone: make(chan struct{}), config: config, } @@ -340,16 +342,17 @@ write: t.mu.Unlock() } + // Unblock reader. + t.conn.Close() + // drain startKex channel. We don't service t.requestKex // because nobody does blocking sends there. - go func() { - for init := range t.startKex { - init.done <- t.writeError - } - }() + for request := range t.startKex { + request.done <- t.getWriteError() + } - // Unblock reader. - t.conn.Close() + // Mark that the loop is done so that Close can return. + close(t.kexLoopDone) } // The protocol uses uint32 for packet counters, so we can't let them @@ -545,7 +548,16 @@ func (t *handshakeTransport) writePacket(p []byte) error { } func (t *handshakeTransport) Close() error { - return t.conn.Close() + // Close the connection. This should cause the readLoop goroutine to wake up + // and close t.startKex, which will shut down kexLoop if running. + err := t.conn.Close() + + // Wait for the kexLoop goroutine to complete. + // At that point we know that the readLoop goroutine is complete too, + // because kexLoop itself waits for readLoop to close the startKex channel. + <-t.kexLoopDone + + return err } func (t *handshakeTransport) enterKeyExchange(otherInitPacket []byte) error { @@ -615,7 +627,8 @@ func (t *handshakeTransport) enterKeyExchange(otherInitPacket []byte) error { return err } - if t.sessionID == nil { + firstKeyExchange := t.sessionID == nil + if firstKeyExchange { t.sessionID = result.H } result.SessionID = t.sessionID @@ -626,6 +639,24 @@ func (t *handshakeTransport) enterKeyExchange(otherInitPacket []byte) error { if err = t.conn.writePacket([]byte{msgNewKeys}); err != nil { return err } + + // 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. + if !isClient && firstKeyExchange && contains(clientInit.KexAlgos, "ext-info-c") { + extInfo := &extInfoMsg{ + NumExtensions: 1, + Payload: make([]byte, 0, 4+15+4+len(supportedPubKeyAuthAlgosList)), + } + 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...) + if err := t.conn.writePacket(Marshal(extInfo)); err != nil { + return err + } + } + if packet, err := t.conn.readPacket(); err != nil { return err } else if packet[0] != msgNewKeys { |