Land Recent QUIC Changes.

net/quic/quic_connection.cc

Index: net/quic/quic_connection.cc
diff --git a/net/quic/quic_connection.cc b/net/quic/quic_connection.cc
index 6838a1ec30a8c07484d194943f1b5793ff0c9466..d834f207630c5c563c30d154ae966b1554103f71 100644
--- a/net/quic/quic_connection.cc
+++ b/net/quic/quic_connection.cc
@@ -204,6 +204,7 @@ QuicConnection::QuicConnection(QuicConnectionId connection_id,
       random_generator_(helper->GetRandomGenerator()),
       connection_id_(connection_id),
       peer_address_(address),
+      migrating_peer_port_(0),
       last_packet_revived_(false),
       last_size_(0),
       last_decrypted_packet_level_(ENCRYPTION_NONE),
@@ -234,7 +235,10 @@ QuicConnection::QuicConnection(QuicConnectionId connection_id,
       version_negotiation_state_(START_NEGOTIATION),
       is_server_(is_server),
       connected_(true),
-      address_migrating_(false),
+      peer_ip_changed_(false),
+      peer_port_changed_(false),
+      self_ip_changed_(false),
+      self_port_changed_(false),
       max_flow_control_receive_window_bytes_(
           max_flow_control_receive_window_bytes) {
   if (max_flow_control_receive_window_bytes_ < kDefaultFlowControlSendWindow) {
@@ -1105,18 +1109,7 @@ void QuicConnection::ProcessUdpPacket(const IPEndPoint& self_address,
   last_packet_revived_ = false;
   last_size_ = packet.length();
 
-  address_migrating_ = false;
-
-  if (peer_address_.address().empty()) {
-    peer_address_ = peer_address;
-  }
-  if (self_address_.address().empty()) {
-    self_address_ = self_address;
-  }
-
-  if (!(peer_address == peer_address_ && self_address == self_address_)) {
-    address_migrating_ = true;
-  }
+  CheckForAddressMigration(self_address, peer_address);
 
   stats_.bytes_received += packet.length();
   ++stats_.packets_received;
@@ -1141,20 +1134,45 @@ void QuicConnection::ProcessUdpPacket(const IPEndPoint& self_address,
   SetPingAlarm();
 }
 
+void QuicConnection::CheckForAddressMigration(
+    const IPEndPoint& self_address, const IPEndPoint& peer_address) {
+  peer_ip_changed_ = false;
+  peer_port_changed_ = false;
+  self_ip_changed_ = false;
+  self_port_changed_ = false;
+
+  if (peer_address_.address().empty()) {
+    peer_address_ = peer_address;
+  }
+  if (self_address_.address().empty()) {
+    self_address_ = self_address;
+  }
+
+  if (!peer_address.address().empty() && !peer_address_.address().empty()) {
+    peer_ip_changed_ = (peer_address.address() != peer_address_.address());
+    peer_port_changed_ = (peer_address.port() != peer_address_.port());
+
+    // Store in case we want to migrate connection in ProcessValidatedPacket.
+    migrating_peer_port_ = peer_address.port();
+  }
+
+  if (!self_address.address().empty() && !self_address_.address().empty()) {
+    self_ip_changed_ = (self_address.address() != self_address_.address());
+    self_port_changed_ = (self_address.port() != self_address_.port());
+  }
+}
+
 void QuicConnection::OnCanWrite() {
   DCHECK(!writer_->IsWriteBlocked());
 
   WriteQueuedPackets();
   WritePendingRetransmissions();
 
-  IsHandshake pending_handshake = visitor_->HasPendingHandshake() ?
-      IS_HANDSHAKE : NOT_HANDSHAKE;
   // Sending queued packets may have caused the socket to become write blocked,
   // or the congestion manager to prohibit sending.  If we've sent everything
   // we had queued and we're still not blocked, let the visitor know it can
   // write more.
-  if (!CanWrite(NOT_RETRANSMISSION, HAS_RETRANSMITTABLE_DATA,
-                pending_handshake)) {
+  if (!CanWrite(NOT_RETRANSMISSION, HAS_RETRANSMITTABLE_DATA)) {
     return;
   }
 
@@ -1166,11 +1184,8 @@ void QuicConnection::OnCanWrite() {
 
   // After the visitor writes, it may have caused the socket to become write
   // blocked or the congestion manager to prohibit sending, so check again.
-  pending_handshake = visitor_->HasPendingHandshake() ?
-      IS_HANDSHAKE : NOT_HANDSHAKE;
   if (visitor_->HasPendingWrites() && !resume_writes_alarm_->IsSet() &&
-      CanWrite(NOT_RETRANSMISSION, HAS_RETRANSMITTABLE_DATA,
-               pending_handshake)) {
+      CanWrite(NOT_RETRANSMISSION, HAS_RETRANSMITTABLE_DATA)) {
     // We're not write blocked, but some stream didn't write out all of its
     // bytes. Register for 'immediate' resumption so we'll keep writing after
     // other connections and events have had a chance to use the thread.
@@ -1185,12 +1200,23 @@ void QuicConnection::WriteIfNotBlocked() {
 }
 
 bool QuicConnection::ProcessValidatedPacket() {
-  if (address_migrating_) {
+  if ((!FLAGS_quic_allow_port_migration && peer_port_changed_) ||
+      peer_ip_changed_ || self_ip_changed_ || self_port_changed_) {
     SendConnectionCloseWithDetails(
         QUIC_ERROR_MIGRATING_ADDRESS,
-        "Address migration is not yet a supported feature");
+        "IP or port migration is not yet a supported feature");
     return false;
   }
+
+  // Port migration is supported, do it now if port has changed.
+  if (FLAGS_quic_allow_port_migration &&
+      peer_port_changed_) {
+    DVLOG(1) << ENDPOINT << "Peer's port changed from "
+             << peer_address_.port() << " to " << migrating_peer_port_
+             << ", migrating connection.";
+    peer_address_ = IPEndPoint(peer_address_.address(), migrating_peer_port_);
+  }
+
   time_of_last_received_packet_ = clock_->Now();
   DVLOG(1) << ENDPOINT << "time of last received packet: "
            << time_of_last_received_packet_.ToDebuggingValue();
@@ -1230,8 +1256,7 @@ void QuicConnection::WritePendingRetransmissions() {
     const QuicSentPacketManager::PendingRetransmission pending =
         sent_packet_manager_.NextPendingRetransmission();
     if (GetPacketType(&pending.retransmittable_frames) == NORMAL &&
-        !CanWrite(pending.transmission_type, HAS_RETRANSMITTABLE_DATA,
-                  pending.retransmittable_frames.HasCryptoHandshake())) {
+        !CanWrite(pending.transmission_type, HAS_RETRANSMITTABLE_DATA)) {
       break;
     }
 
@@ -1269,8 +1294,8 @@ void QuicConnection::RetransmitUnackedPackets(
   WriteIfNotBlocked();
 }
 
-void QuicConnection::DiscardUnencryptedPackets() {
-  sent_packet_manager_.DiscardUnencryptedPackets();
+void QuicConnection::NeuterUnencryptedPackets() {
+  sent_packet_manager_.NeuterUnencryptedPackets();
   // This may have changed the retransmission timer, so re-arm it.
   retransmission_alarm_->Cancel();
   QuicTime retransmission_time = sent_packet_manager_.GetRetransmissionTime();
@@ -1289,12 +1314,11 @@ bool QuicConnection::ShouldGeneratePacket(
     return true;
   }
 
-  return CanWrite(transmission_type, retransmittable, handshake);
+  return CanWrite(transmission_type, retransmittable);
 }
 
 bool QuicConnection::CanWrite(TransmissionType transmission_type,
-                              HasRetransmittableData retransmittable,
-                              IsHandshake handshake) {
+                              HasRetransmittableData retransmittable) {
   if (writer_->IsWriteBlocked()) {
     visitor_->OnWriteBlocked();
     return false;
@@ -1342,8 +1366,7 @@ bool QuicConnection::WritePacket(QueuedPacket packet) {
   // TODO(ianswett): The congestion control should have been consulted before
   // serializing the packet, so this could be turned into a LOG_IF(DFATAL).
   if (packet.type == NORMAL && !CanWrite(packet.transmission_type,
-                                         packet.retransmittable,
-                                         packet.handshake)) {
+                                         packet.retransmittable)) {
     return false;
   }