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

net/quic/quic_stream_factory.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_STREAM_FACTORY_H_
 #define NET_QUIC_QUIC_STREAM_FACTORY_H_
 
 #include <list>
 #include <map>
 #include <string>
@@ skipping 88 matching lines @@
   CompletionCallback callback_;
   scoped_ptr<QuicHttpStream> stream_;
 
   DISALLOW_COPY_AND_ASSIGN(QuicStreamRequest);
 };
 
 // A factory for creating new QuicHttpStreams on top of a pool of
 // QuicChromiumClientSessions.
 class NET_EXPORT_PRIVATE QuicStreamFactory
     : public NetworkChangeNotifier::IPAddressObserver,
+      public NetworkChangeNotifier::NetworkObserver,
       public SSLConfigService::Observer,
       public CertDatabase::Observer {
  public:
   QuicStreamFactory(
       HostResolver* host_resolver,
       ClientSocketFactory* client_socket_factory,
       base::WeakPtr<HttpServerProperties> http_server_properties,
       CertVerifier* cert_verifier,
       CertPolicyEnforcer* cert_policy_enforcer,
       ChannelIDService* channel_id_service,
@@ skipping 15 matching lines @@
       bool prefer_aes,
       int max_number_of_lossy_connections,
       float packet_loss_threshold,
       int max_recent_disabled_reasons,
       int threshold_timeouts_with_streams_open,
       int threshold_public_resets_post_handshake,
       int socket_receive_buffer_size,
       bool delay_tcp_race,
       bool store_server_configs_in_properties,
       bool close_sessions_on_ip_change,
+      bool migrate_sessions_on_net_change,
       const QuicTagVector& connection_options);
   ~QuicStreamFactory() override;
 
   // Creates a new QuicHttpStream to |host_port_pair| which will be
   // owned by |request|. |is_https| specifies if the protocol is https or not.
   // If a matching session already exists, this method will return OK.  If no
   // matching session exists, this will return ERR_IO_PENDING and will invoke
   // OnRequestComplete asynchronously.
   int Create(const HostPortPair& host_port_pair,
              bool is_https,
@@ skipping 42 matching lines @@
   void CancelRequest(QuicStreamRequest* request);
 
   // Closes all current sessions.
   void CloseAllSessions(int error);
 
   scoped_ptr<base::Value> QuicStreamFactoryInfoToValue() const;
 
   // Delete all cached state objects in |crypto_config_|.
   void ClearCachedStatesInCryptoConfig();
 
+  // Helper method that creates and returns a DatagramClientSocket.
+  scoped_ptr<DatagramClientSocket> 
+      CreateDatagramClientSocket(const QuicServerId& server_id, 
+                                 const BoundNetLog& net_log);
+
+  // Helper method that configures a DatagramClientSocket.
+  // Returns net_error code.
+  int ConfigureDatagramClientSocket(DatagramClientSocket* socket, 
+                                    IPEndPoint addr,
+                                    NetworkChangeNotifier::NetworkHandle 
+                                        network);
+
+  // Helper method that initiates migration of active sessions away from 
+  // |network| if possible, and if not, closes them. Migration is only 
+  // attempted on active sessions; idle sessions are closed.
+  void MigrateOrCloseSessions(NetworkChangeNotifier::NetworkHandle);
+
   // NetworkChangeNotifier::IPAddressObserver methods:
 
   // Until the servers support roaming, close all connections when the local
   // IP address changes.
   void OnIPAddressChanged() override;
 
+  // NetworkChangeNotifier::NetworkObserver methods:
+  void OnNetworkConnected(NetworkChangeNotifier::NetworkHandle network)
+      override;
+  void OnNetworkDisconnected(NetworkChangeNotifier::NetworkHandle network)
+      override;
+  void OnNetworkSoonToDisconnect(NetworkChangeNotifier::NetworkHandle network)
+      override;
+  void OnNetworkMadeDefault(NetworkChangeNotifier::NetworkHandle network)
+      override;
+
   // SSLConfigService::Observer methods:
 
   // We perform the same flushing as described above when SSL settings change.
   void OnSSLConfigChanged() override;
 
   // CertDatabase::Observer methods:
 
   // We close all sessions when certificate database is changed.
   void OnCertAdded(const X509Certificate* cert) override;
   void OnCACertChanged(const X509Certificate* cert) override;
@@ skipping 232 matching lines @@
   int yield_after_packets_;
   QuicTime::Delta yield_after_duration_;
 
   // Set if server configs are to be stored in HttpServerProperties.
   bool store_server_configs_in_properties_;
 
   // Set if sessions should be closed when the IP address of the primary
   // interface changes.
   const bool close_sessions_on_ip_change_;
 
+  // Set if migration should be attempted on active sessions when primary
+  // interface changes.
+  const bool migrate_sessions_on_net_change_;
+
   // Each profile will (probably) have a unique port_seed_ value.  This value
   // is used to help seed a pseudo-random number generator (PortSuggester) so
   // that we consistently (within this profile) suggest the same ephemeral
   // port when we re-connect to any given server/port.  The differences between
   // profiles (probablistically) prevent two profiles from colliding in their
   // ephemeral port requests.
   uint64 port_seed_;
 
   // Local address of socket that was created in CreateSession.
   IPEndPoint local_address_;
   bool check_persisted_supports_quic_;
   bool has_initialized_data_;
   std::set<HostPortPair> quic_supported_servers_at_startup_;
 
   NetworkConnection network_connection_;
 
   base::TaskRunner* task_runner_;
 
   base::WeakPtrFactory<QuicStreamFactory> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(QuicStreamFactory);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_QUIC_STREAM_FACTORY_H_