Merge pull request #3138 from lucas-clemente/pmtud-after-handshake-co…

…nfirmation

only start PMTUD after handshake confirmation

session.go

@@ -747,10 +747,10 @@ func (s *session) maybeResetTimer() {
 		} else {
 			deadline = s.idleTimeoutStartTime().Add(s.idleTimeout)
 		}
-		if !s.config.DisablePathMTUDiscovery {
-			if probeTime := s.mtuDiscoverer.NextProbeTime(); !probeTime.IsZero() {
-				deadline = utils.MinTime(deadline, probeTime)
-			}
+	}
+	if s.handshakeConfirmed && !s.config.DisablePathMTUDiscovery {
+		if probeTime := s.mtuDiscoverer.NextProbeTime(); !probeTime.IsZero() {
+			deadline = utils.MinTime(deadline, probeTime)
 		}
 	}
 
@@ -782,30 +782,13 @@ func (s *session) handleHandshakeComplete() {
 	s.connIDManager.SetHandshakeComplete()
 	s.connIDGenerator.SetHandshakeComplete()
 
-	if !s.config.DisablePathMTUDiscovery {
-		maxPacketSize := s.peerParams.MaxUDPPayloadSize
-		if maxPacketSize == 0 {
-			maxPacketSize = protocol.MaxByteCount
-		}
-		maxPacketSize = utils.MinByteCount(maxPacketSize, protocol.MaxPacketBufferSize)
-		s.mtuDiscoverer = newMTUDiscoverer(
-			s.rttStats,
-			getMaxPacketSize(s.conn.RemoteAddr()),
-			maxPacketSize,
-			func(size protocol.ByteCount) {
-				s.sentPacketHandler.SetMaxDatagramSize(size)
-				s.packer.SetMaxPacketSize(size)
-			},
-		)
-	}
-
 	if s.perspective == protocol.PerspectiveClient {
 		s.applyTransportParameters()
 		return
 	}
 
-	s.handshakeConfirmed = true
-	s.sentPacketHandler.SetHandshakeConfirmed()
+	s.handleHandshakeConfirmed()
+
 	ticket, err := s.cryptoStreamHandler.GetSessionTicket()
 	if err != nil {
 		s.closeLocal(err)
@@ -821,10 +804,32 @@ func (s *session) handleHandshakeComplete() {
 		s.closeLocal(err)
 	}
 	s.queueControlFrame(&wire.NewTokenFrame{Token: token})
-	s.cryptoStreamHandler.SetHandshakeConfirmed()
 	s.queueControlFrame(&wire.HandshakeDoneFrame{})
 }
 
+func (s *session) handleHandshakeConfirmed() {
+	s.handshakeConfirmed = true
+	s.sentPacketHandler.SetHandshakeConfirmed()
+	s.cryptoStreamHandler.SetHandshakeConfirmed()
+
+	if !s.config.DisablePathMTUDiscovery {
+		maxPacketSize := s.peerParams.MaxUDPPayloadSize
+		if maxPacketSize == 0 {
+			maxPacketSize = protocol.MaxByteCount
+		}
+		maxPacketSize = utils.MinByteCount(maxPacketSize, protocol.MaxPacketBufferSize)
+		s.mtuDiscoverer = newMTUDiscoverer(
+			s.rttStats,
+			getMaxPacketSize(s.conn.RemoteAddr()),
+			maxPacketSize,
+			func(size protocol.ByteCount) {
+				s.sentPacketHandler.SetMaxDatagramSize(size)
+				s.packer.SetMaxPacketSize(size)
+			},
+		)
+	}
+}
+
 func (s *session) handlePacketImpl(rp *receivedPacket) bool {
 	if wire.IsVersionNegotiationPacket(rp.data) {
 		s.handleVersionNegotiationPacket(rp)
@@ -1349,9 +1354,9 @@ func (s *session) handleHandshakeDoneFrame() error {
 	if s.perspective == protocol.PerspectiveServer {
 		return qerr.NewError(qerr.ProtocolViolation, "received a HANDSHAKE_DONE frame")
 	}
-	s.handshakeConfirmed = true
-	s.sentPacketHandler.SetHandshakeConfirmed()
-	s.cryptoStreamHandler.SetHandshakeConfirmed()
+	if !s.handshakeConfirmed {
+		s.handleHandshakeConfirmed()
+	}
 	return nil
 }
 
@@ -1716,7 +1721,7 @@ func (s *session) sendPacket() (bool, error) {
 		s.sendQueue.Send(packet.buffer)
 		return true, nil
 	}
-	if !s.config.DisablePathMTUDiscovery && s.handshakeComplete && s.mtuDiscoverer.ShouldSendProbe(now) {
+	if !s.config.DisablePathMTUDiscovery && s.mtuDiscoverer.ShouldSendProbe(now) {
 		packet, err := s.packer.PackMTUProbePacket(s.mtuDiscoverer.GetPing())
 		if err != nil {
 			return false, err

session_test.go

@@ -2555,6 +2555,7 @@ var _ = Describe("Client Session", func() {
 	})
 
 	It("handles HANDSHAKE_DONE frames", func() {
+		sess.peerParams = &wire.TransportParameters{}
 		sph := mockackhandler.NewMockSentPacketHandler(mockCtrl)
 		sess.sentPacketHandler = sph
 		sph.EXPECT().SetHandshakeConfirmed()