go-tls-renegotiation patch

go-tls-renegotiation patch

diff -r c242bbf5fa8c src/pkg/crypto/tls/common.go
--- a/src/pkg/crypto/tls/common.go	Wed Jul 17 14:03:27 2013 -0400
+++ b/src/pkg/crypto/tls/common.go	Thu Jul 18 13:45:43 2013 -0400
@@ -44,6 +44,7 @@
 
 // TLS handshake message types.
 const (
+	typeHelloRequest       uint8 = 0
 	typeClientHello        uint8 = 1
 	typeServerHello        uint8 = 2
 	typeNewSessionTicket   uint8 = 4
diff -r c242bbf5fa8c src/pkg/crypto/tls/conn.go
--- a/src/pkg/crypto/tls/conn.go	Wed Jul 17 14:03:27 2013 -0400
+++ b/src/pkg/crypto/tls/conn.go	Thu Jul 18 13:45:43 2013 -0400
@@ -146,6 +146,9 @@
 	hc.mac = hc.nextMac
 	hc.nextCipher = nil
 	hc.nextMac = nil
+	for i := range hc.seq {
+		hc.seq[i] = 0
+	}
 	return nil
 }
 
@@ -478,7 +481,7 @@
 func (c *Conn) readRecord(want recordType) error {
 	// Caller must be in sync with connection:
 	// handshake data if handshake not yet completed,
-	// else application data.  (We don't support renegotiation.)
+	// else application data.
 	switch want {
 	default:
 		return c.sendAlert(alertInternalError)
@@ -611,7 +614,7 @@
 
 	case recordTypeHandshake:
 		// TODO(rsc): Should at least pick off connection close.
-		if typ != want {
+		if typ != want && !c.isClient {
 			return c.sendAlert(alertNoRenegotiation)
 		}
 		c.hand.Write(data)
@@ -741,6 +744,8 @@
 	data = c.hand.Next(4 + n)
 	var m handshakeMessage
 	switch data[0] {
+	case typeHelloRequest:
+		m = new(helloRequestMsg)
 	case typeClientHello:
 		m = new(clientHelloMsg)
 	case typeServerHello:
@@ -825,6 +830,25 @@
 	return n + m, c.setError(err)
 }
 
+func (c *Conn) handleRenegotiation() error {
+	c.handshakeComplete = false
+	if !c.isClient {
+		panic("renegotiation should only happen for a client")
+	}
+
+	msg, err := c.readHandshake()
+	if err != nil {
+		return err
+	}
+	_, ok := msg.(*helloRequestMsg)
+	if !ok {
+		c.sendAlert(alertUnexpectedMessage)
+		return alertUnexpectedMessage
+	}
+
+	return c.Handshake()
+}
+
 // Read can be made to time out and return a net.Error with Timeout() == true
 // after a fixed time limit; see SetDeadline and SetReadDeadline.
 func (c *Conn) Read(b []byte) (n int, err error) {
@@ -844,6 +868,14 @@
 				// Soft error, like EAGAIN
 				return 0, err
 			}
+			if c.hand.Len() > 0 {
+				// We received handshake bytes, indicating the start of
+				// a renegotiation.
+				if err := c.handleRenegotiation(); err != nil {
+					return 0, err
+				}
+				continue
+			}
 		}
 		if err := c.error(); err != nil {
 			return 0, err
diff -r c242bbf5fa8c src/pkg/crypto/tls/handshake_messages.go
--- a/src/pkg/crypto/tls/handshake_messages.go	Wed Jul 17 14:03:27 2013 -0400
+++ b/src/pkg/crypto/tls/handshake_messages.go	Thu Jul 18 13:45:43 2013 -0400
@@ -1243,6 +1243,17 @@
 	return true
 }
 
+type helloRequestMsg struct {
+}
+
+func (*helloRequestMsg) marshal() []byte {
+	return []byte{typeHelloRequest, 0, 0, 0}
+}
+
+func (*helloRequestMsg) unmarshal(data []byte) bool {
+	return len(data) == 4
+}
+
 func eqUint16s(x, y []uint16) bool {
 	if len(x) != len(y) {
 		return false