src/net/quic/quic_dispatcher.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4 //
   5 // A server side dispatcher which dispatches a given client's data to their
   6 // stream.
   7
   8 #ifndef NET_QUIC_QUIC_DISPATCHER_H_
   9 #define NET_QUIC_QUIC_DISPATCHER_H_
  10
  11 #include <list>
  12
  13 #include "base/basictypes.h"
  14 #include "base/containers/hash_tables.h"
  15 #include "base/memory/scoped_ptr.h"
  16 #include "net/base/ip_endpoint.h"
  17 #include "net/base/linked_hash_map.h"
  18 #include "net/quic/quic_blocked_writer_interface.h"
  19 #include "net/quic/quic_connection_helper.h"
  20 #include "net/quic/quic_protocol.h"
  21 #include "net/quic/quic_server_packet_writer.h"
  22 #include "net/quic/quic_server_session.h"
  23 #include "net/quic/quic_time_wait_list_manager.h"
  24
  25 namespace net {
  26 namespace test {
  27 class QuicDispatcherPeer;
  28 }  // namespace test
  29
  30 class DeleteSessionsAlarm;
  31 class QuicConfig;
  32 class QuicCryptoServerConfig;
  33 class QuicSession;
  34
  35 class ProcessPacketInterface {
  36  public:
  37   virtual ~ProcessPacketInterface() {}
  38   virtual void ProcessPacket(const IPEndPoint& server_address,
  39                              const IPEndPoint& client_address,
  40                              const QuicEncryptedPacket& packet) = 0;
  41 };
  42
  43 class QuicDispatcher : public QuicBlockedWriterInterface,
  44                        public QuicServerSessionVisitor,
  45                        public ProcessPacketInterface {
  46  public:
  47   // Creates per-connection packet writers out of the QuicDispatcher's shared
  48   // QuicPacketWriter. The per-connection writers' IsWriteBlocked() state must
  49   // always be the same as the shared writer's IsWriteBlocked(), or else the
  50   // QuicDispatcher::OnCanWrite logic will not work. (This will hopefully be
  51   // cleaned up for bug 16950226.)
  52   class PacketWriterFactory {
  53    public:
  54     virtual ~PacketWriterFactory() {}
  55
  56     virtual QuicPacketWriter* Create(QuicServerPacketWriter* writer,
  57                                      QuicConnection* connection) = 0;
  58   };
  59
  60   // Creates ordinary QuicPerConnectionPacketWriter instances.
  61   class DefaultPacketWriterFactory : public PacketWriterFactory {
  62    public:
  63     ~DefaultPacketWriterFactory() override {}
  64
  65     QuicPacketWriter* Create(QuicServerPacketWriter* writer,
  66                              QuicConnection* connection) override;
  67   };
  68
  69   // Ideally we'd have a linked_hash_set: the  boolean is unused.
  70   typedef linked_hash_map<QuicBlockedWriterInterface*, bool> WriteBlockedList;
  71
  72   // Due to the way delete_sessions_closure_ is registered, the Dispatcher must
  73   // live until epoll_server Shutdown. |supported_versions| specifies the list
  74   // of supported QUIC versions. Takes ownership of |packet_writer_factory|,
  75   // which is used to create per-connection writers.
  76   QuicDispatcher(const QuicConfig& config,
  77                  const QuicCryptoServerConfig& crypto_config,
  78                  const QuicVersionVector& supported_versions,
  79                  PacketWriterFactory* packet_writer_factory,
  80                  QuicConnectionHelperInterface* helper);
  81
  82   ~QuicDispatcher() override;
  83
  84   // Takes ownership of the packet writer.
  85   virtual void Initialize(QuicServerPacketWriter* writer);
  86
  87   // Process the incoming packet by creating a new session, passing it to
  88   // an existing session, or passing it to the TimeWaitListManager.
  89   void ProcessPacket(const IPEndPoint& server_address,
  90                      const IPEndPoint& client_address,
  91                      const QuicEncryptedPacket& packet) override;
  92
  93   // Returns true if there's anything in the blocked writer list.
  94   virtual bool HasPendingWrites() const;
  95
  96   // Sends ConnectionClose frames to all connected clients.
  97   void Shutdown();
  98
  99   // QuicBlockedWriterInterface implementation:
 100   // Called when the socket becomes writable to allow queued writes to happen.
 101   void OnCanWrite() override;
 102
 103   // QuicServerSessionVisitor interface implementation:
 104   // Ensure that the closed connection is cleaned up asynchronously.
 105   void OnConnectionClosed(QuicConnectionId connection_id,
 106                           QuicErrorCode error) override;
 107
 108   // Queues the blocked writer for later resumption.
 109   void OnWriteBlocked(QuicBlockedWriterInterface* blocked_writer) override;
 110
 111   typedef base::hash_map<QuicConnectionId, QuicSession*> SessionMap;
 112
 113   // Deletes all sessions on the closed session list and clears the list.
 114   void DeleteSessions();
 115
 116   const SessionMap& session_map() const { return session_map_; }
 117
 118  protected:
 119   virtual QuicSession* CreateQuicSession(QuicConnectionId connection_id,
 120                                          const IPEndPoint& server_address,
 121                                          const IPEndPoint& client_address);
 122
 123   virtual QuicConnection* CreateQuicConnection(
 124       QuicConnectionId connection_id,
 125       const IPEndPoint& server_address,
 126       const IPEndPoint& client_address);
 127
 128   // Called by |framer_visitor_| when the public header has been parsed.
 129   virtual bool OnUnauthenticatedPublicHeader(
 130       const QuicPacketPublicHeader& header);
 131
 132   // Create and return the time wait list manager for this dispatcher, which
 133   // will be owned by the dispatcher as time_wait_list_manager_
 134   virtual QuicTimeWaitListManager* CreateQuicTimeWaitListManager();
 135
 136   // Replaces the packet writer with |writer|. Takes ownership of |writer|.
 137   void set_writer(QuicServerPacketWriter* writer) {
 138     writer_.reset(writer);
 139   }
 140
 141   QuicTimeWaitListManager* time_wait_list_manager() {
 142     return time_wait_list_manager_.get();
 143   }
 144
 145   const QuicVersionVector& supported_versions() const {
 146     return supported_versions_;
 147   }
 148
 149   const IPEndPoint& current_server_address() {
 150     return current_server_address_;
 151   }
 152   const IPEndPoint& current_client_address() {
 153     return current_client_address_;
 154   }
 155   const QuicEncryptedPacket& current_packet() {
 156     return *current_packet_;
 157   }
 158
 159   const QuicConfig& config() const { return config_; }
 160
 161   const QuicCryptoServerConfig& crypto_config() const { return crypto_config_; }
 162
 163   QuicFramer* framer() { return &framer_; }
 164
 165   QuicConnectionHelperInterface* helper() { return helper_; }
 166
 167   QuicServerPacketWriter* writer() { return writer_.get(); }
 168
 169   const QuicConnection::PacketWriterFactory& connection_writer_factory() {
 170     return connection_writer_factory_;
 171   }
 172
 173  private:
 174   class QuicFramerVisitor;
 175   friend class net::test::QuicDispatcherPeer;
 176
 177   // An adapter that creates packet writers using the dispatcher's
 178   // PacketWriterFactory and shared writer. Essentially, it just curries the
 179   // writer argument away from QuicDispatcher::PacketWriterFactory.
 180   class PacketWriterFactoryAdapter :
 181     public QuicConnection::PacketWriterFactory {
 182    public:
 183     PacketWriterFactoryAdapter(QuicDispatcher* dispatcher);
 184     ~PacketWriterFactoryAdapter() override;
 185
 186     QuicPacketWriter* Create(QuicConnection* connection) const override;
 187
 188    private:
 189     QuicDispatcher* dispatcher_;
 190   };
 191
 192   // Called by |framer_visitor_| when the private header has been parsed
 193   // of a data packet that is destined for the time wait manager.
 194   void OnUnauthenticatedHeader(const QuicPacketHeader& header);
 195
 196   // Removes the session from the session map and write blocked list, and
 197   // adds the ConnectionId to the time-wait list.
 198   void CleanUpSession(SessionMap::iterator it);
 199
 200   bool HandlePacketForTimeWait(const QuicPacketPublicHeader& header);
 201
 202   const QuicConfig& config_;
 203
 204   const QuicCryptoServerConfig& crypto_config_;
 205
 206   // The list of connections waiting to write.
 207   WriteBlockedList write_blocked_list_;
 208
 209   SessionMap session_map_;
 210
 211   // Entity that manages connection_ids in time wait state.
 212   scoped_ptr<QuicTimeWaitListManager> time_wait_list_manager_;
 213
 214   // The helper used for all connections. Owned by the server.
 215   QuicConnectionHelperInterface* helper_;
 216
 217   // An alarm which deletes closed sessions.
 218   scoped_ptr<QuicAlarm> delete_sessions_alarm_;
 219
 220   // The list of closed but not-yet-deleted sessions.
 221   std::list<QuicSession*> closed_session_list_;
 222
 223   // The writer to write to the socket with.
 224   scoped_ptr<QuicServerPacketWriter> writer_;
 225
 226   // Used to create per-connection packet writers, not |writer_| itself.
 227   scoped_ptr<PacketWriterFactory> packet_writer_factory_;
 228
 229   // Passed in to QuicConnection for it to create the per-connection writers
 230   PacketWriterFactoryAdapter connection_writer_factory_;
 231
 232   // This vector contains QUIC versions which we currently support.
 233   // This should be ordered such that the highest supported version is the first
 234   // element, with subsequent elements in descending order (versions can be
 235   // skipped as necessary).
 236   const QuicVersionVector supported_versions_;
 237
 238   // Information about the packet currently being handled.
 239   IPEndPoint current_client_address_;
 240   IPEndPoint current_server_address_;
 241   const QuicEncryptedPacket* current_packet_;
 242
 243   QuicFramer framer_;
 244   scoped_ptr<QuicFramerVisitor> framer_visitor_;
 245
 246   DISALLOW_COPY_AND_ASSIGN(QuicDispatcher);
 247 };
 248
 249 }  // namespace net
 250
 251 #endif  // NET_QUIC_QUIC_DISPATCHER_H_