eiac/crypto
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

go.crypto/ssh: move interpretation of msgNewKeys into

Browse Source 
transport.

Sending the msgNewKeys packet and setting up the key material
now happen under a lock, preventing races with concurrent
writers.

R=kardianos, agl, jpsugar, hanwenn
CC=golang-dev
https://golang.org/cl/14476043
This commit is contained in:
Han-Wen Nienhuys
2013-10-08 15:47:04 -04:00
committed by Adam Langley
parent 41400feb0b
commit 4147256c9c
5 changed files with 138 additions and 80 deletions
Download Patch File Download Diff File Expand all files Collapse all files
ssh/server.go
+14 -28
View File
@@ -121,17 +121,13 @@ type ServerConn struct {
// ClientVersion is the client's version, populated after
// Handshake is called. It should not be modified.
ClientVersion []byte
// Initial H used for the session ID. Once assigned this must not change
// even during subsequent key exchanges.
sessionId []byte
}
// Server returns a new SSH server connection
// using c as the underlying transport.
func Server(c net.Conn, config *ServerConfig) *ServerConn {
return &ServerConn{
transport: newTransport(c, config.rand()),
transport: newTransport(c, config.rand(), false /* not client */),
channels: make(map[uint32]*serverChan),
config: config,
}
@@ -186,7 +182,7 @@ func (s *ServerConn) Handshake() (err error) {
return
}
if err = s.authenticate(s.sessionId); err != nil {
if err = s.authenticate(s.transport.sessionID); err != nil {
return
}
return
@@ -222,11 +218,12 @@ func (s *ServerConn) clientInitHandshake(clientKexInit *kexInitMsg, clientKexIni
}
}
kexAlgo, hostKeyAlgo, ok := findAgreedAlgorithms(s.transport, clientKexInit, &serverKexInit)
if !ok {
algs := findAgreedAlgorithms(clientKexInit, &serverKexInit)
if algs == nil {
return errors.New("ssh: no common algorithms")
}
if clientKexInit.FirstKexFollows && kexAlgo != clientKexInit.KexAlgos[0] {
if clientKexInit.FirstKexFollows && algs.kex != clientKexInit.KexAlgos[0] {
// The client sent a Kex message for the wrong algorithm,
// which we have to ignore.
if _, err = s.readPacket(); err != nil {
@@ -236,14 +233,14 @@ func (s *ServerConn) clientInitHandshake(clientKexInit *kexInitMsg, clientKexIni
var hostKey Signer
for _, k := range s.config.hostKeys {
if hostKeyAlgo == k.PublicKey().PublicKeyAlgo() {
if algs.hostKey == k.PublicKey().PublicKeyAlgo() {
hostKey = k
}
}
kex, ok := kexAlgoMap[kexAlgo]
kex, ok := kexAlgoMap[algs.kex]
if !ok {
return fmt.Errorf("ssh: unexpected key exchange algorithm %v", kexAlgo)
return fmt.Errorf("ssh: unexpected key exchange algorithm %v", algs.kex)
}
magics := handshakeMagics{
@@ -257,29 +254,18 @@ func (s *ServerConn) clientInitHandshake(clientKexInit *kexInitMsg, clientKexIni
return err
}
// sessionId must only be assigned during initial handshake.
if s.sessionId == nil {
s.sessionId = result.H
if err = s.transport.prepareKeyChange(algs, result); err != nil {
return err
}
var packet []byte
if err = s.writePacket([]byte{msgNewKeys}); err != nil {
return
}
if err = s.transport.writer.setupKeys(serverKeys, result.K, result.H, s.sessionId, kex.Hash()); err != nil {
return
}
if packet, err = s.readPacket(); err != nil {
return
}
if packet[0] != msgNewKeys {
if packet, err := s.readPacket(); err != nil {
return err
} else if packet[0] != msgNewKeys {
return UnexpectedMessageError{msgNewKeys, packet[0]}
}
if err = s.transport.reader.setupKeys(clientKeys, result.K, result.H, s.sessionId, kex.Hash()); err != nil {
return
}
return
}