diff options
Diffstat (limited to 'obfs4.go')
| -rw-r--r-- | obfs4.go | 20 |
1 files changed, 14 insertions, 6 deletions
@@ -159,7 +159,6 @@ func (c *Obfs4Conn) clientHandshake(nodeID *ntor.NodeID, publicKey *ntor.PublicK } defer func() { - // The session key is not needed past returning from this routine. c.sessionKey = nil if err != nil { c.setBroken() @@ -169,10 +168,7 @@ func (c *Obfs4Conn) clientHandshake(nodeID *ntor.NodeID, publicKey *ntor.PublicK // Generate/send the client handshake. var hs *clientHandshake var blob []byte - hs, err = newClientHandshake(nodeID, publicKey, c.sessionKey) - if err != nil { - return - } + hs = newClientHandshake(nodeID, publicKey, c.sessionKey) blob, err = hs.generateHandshake() if err != nil { return @@ -231,12 +227,13 @@ func (c *Obfs4Conn) serverHandshake(nodeID *ntor.NodeID, keypair *ntor.Keypair) } defer func() { + c.sessionKey = nil if err != nil { c.setBroken() } }() - hs := newServerHandshake(nodeID, keypair) + hs := newServerHandshake(nodeID, keypair, c.sessionKey) err = c.conn.SetDeadline(time.Now().Add(connectionTimeout)) if err != nil { return @@ -645,6 +642,17 @@ func (l *Obfs4Listener) AcceptObfs4() (*Obfs4Conn, error) { // Allocate the obfs4 connection state. cObfs := new(Obfs4Conn) + + // Generate the session keypair *before* consuming data from the peer, to + // add more noise to the keypair generation time. The idea is that jitter + // here is masked by network latency (the time it takes for a server to + // accept a socket out of the backlog should not be fixed, and the client + // needs to send the public key). + cObfs.sessionKey, err = ntor.NewKeypair(true) + if err != nil { + return nil, err + } + cObfs.conn = c cObfs.isServer = true cObfs.listener = l |