Migrates QUIC sessions to a new network when old network is (about to be) disconnected.

net/quic/quic_protocol.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef NET_QUIC_QUIC_PROTOCOL_H_
 #define NET_QUIC_QUIC_PROTOCOL_H_
 
 #include <stddef.h>
 #include <stdint.h>
 #include <limits>
@@ skipping 616 matching lines @@
   QUIC_CRYPTO_SYMMETRIC_KEY_SETUP_FAILED = 53,
   // A handshake message arrived, but we are still validating the
   // previous handshake message.
   QUIC_CRYPTO_MESSAGE_WHILE_VALIDATING_CLIENT_HELLO = 54,
   // A server config update arrived before the handshake is complete.
   QUIC_CRYPTO_UPDATE_BEFORE_HANDSHAKE_COMPLETE = 65,
   // This connection involved a version negotiation which appears to have been
   // tampered with.
   QUIC_VERSION_NEGOTIATION_MISMATCH = 55,
 
+  // IP address changed causing connection close.
+  QUIC_IP_ADDRESS_CHANGED = 77,

[Ryan Hamilton, 2015/12/18 21:51:23]

Do we expect this to go away in favor of the MIGRATION ones?

[Jana, 2015/12/21 23:10:19]

Eventually, on Android devices. But we don't yet have the MIGRATION
notifications for non-Android devices, so this will remain around for the
platforms where IPAddressChanged exists. I know that set is larger than
{Android}, but I don't know what else it contains.

+
+  // Connection migration errors.
+  // Network changed, but connection had no migratable streams.
+  QUIC_CONNECTION_MIGRATION_NO_MIGRATABLE_STREAMS = 78,

[Ryan Hamilton, 2015/12/18 21:51:23]

How different is this from IP_ADDRESS_CHANGED?

[Jana, 2015/12/21 23:10:19]

This is when migration could have happened, but didn't because there were no
"active" streams. It's different in that IP_ADDRESS_CHANGED means active streams
may have been reset, but here, there were no active streams. Make sense?

+  // Connection changed networks too many times.
+  QUIC_CONNECTION_MIGRATION_TOO_MANY_CHANGES = 79,
+  // Connection migration was attempted, but there was no new network to
+  // migrate to.
+  QUIC_CONNECTION_MIGRATION_NO_NEW_NETWORK = 80,
+
   // No error. Used as bound while iterating.
-  QUIC_LAST_ERROR = 77,
+  QUIC_LAST_ERROR = 81,
 };
 
 // Must be updated any time a QuicErrorCode is deprecated.
 const int kDeprecatedQuicErrorCount = 4;
 const int kActiveQuicErrorCount = QUIC_LAST_ERROR - kDeprecatedQuicErrorCount;
 
 struct NET_EXPORT_PRIVATE QuicPacketPublicHeader {
   QuicPacketPublicHeader();
   explicit QuicPacketPublicHeader(const QuicPacketPublicHeader& other);
   ~QuicPacketPublicHeader();
@@ skipping 631 matching lines @@
       : iov(iov), iov_count(iov_count), total_length(total_length) {}
 
   const struct iovec* iov;
   const int iov_count;
   const size_t total_length;
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_QUIC_PROTOCOL_H_