Home | History | Annotate | Download | only in base 
      1 /*
      2  * libjingle
      3  * Copyright 2004--2005, Google Inc.
      4  *
      5  * Redistribution and use in source and binary forms, with or without
      6  * modification, are permitted provided that the following conditions are met:
      7  *
      8  *  1. Redistributions of source code must retain the above copyright notice,
      9  *     this list of conditions and the following disclaimer.
     10  *  2. Redistributions in binary form must reproduce the above copyright notice,
     11  *     this list of conditions and the following disclaimer in the documentation
     12  *     and/or other materials provided with the distribution.
     13  *  3. The name of the author may not be used to endorse or promote products
     14  *     derived from this software without specific prior written permission.
     15  *
     16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
     17  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
     18  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
     19  * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     20  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     21  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
     22  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
     23  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
     24  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
     25  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     26  */
     27 
     28 #ifndef TALK_P2P_BASE_RELAYSERVER_H_
     29 #define TALK_P2P_BASE_RELAYSERVER_H_
     30 
     31 #include <string>
     32 #include <vector>
     33 #include <map>
     34 
     35 #include "talk/base/asyncudpsocket.h"
     36 #include "talk/base/socketaddresspair.h"
     37 #include "talk/base/thread.h"
     38 #include "talk/base/time.h"
     39 #include "talk/p2p/base/port.h"
     40 #include "talk/p2p/base/stun.h"
     41 
     42 namespace cricket {
     43 
     44 class RelayServerBinding;
     45 class RelayServerConnection;
     46 
     47 // Relays traffic between connections to the server that are "bound" together.
     48 // All connections created with the same username/password are bound together.
     49 class RelayServer : public talk_base::MessageHandler,
     50                     public sigslot::has_slots<> {
     51  public:
     52   // Creates a server, which will use this thread to post messages to itself.
     53   explicit RelayServer(talk_base::Thread* thread);
     54   ~RelayServer();
     55 
     56   talk_base::Thread* thread() { return thread_; }
     57 
     58   // Indicates whether we will print updates of the number of bindings.
     59   bool log_bindings() const { return log_bindings_; }
     60   void set_log_bindings(bool log_bindings) { log_bindings_ = log_bindings; }
     61 
     62   // Updates the set of sockets that the server uses to talk to "internal"
     63   // clients.  These are clients that do the "port allocations".
     64   void AddInternalSocket(talk_base::AsyncPacketSocket* socket);
     65   void RemoveInternalSocket(talk_base::AsyncPacketSocket* socket);
     66 
     67   // Updates the set of sockets that the server uses to talk to "external"
     68   // clients.  These are the clients that do not do allocations.  They do not
     69   // know that these addresses represent a relay server.
     70   void AddExternalSocket(talk_base::AsyncPacketSocket* socket);
     71   void RemoveExternalSocket(talk_base::AsyncPacketSocket* socket);
     72 
     73   // Starts listening for connections on this sockets. When someone
     74   // tries to connect, the connection will be accepted and a new
     75   // internal socket will be added.
     76   void AddInternalServerSocket(talk_base::AsyncSocket* socket,
     77                                cricket::ProtocolType proto);
     78 
     79   // Removes this server socket from the list.
     80   void RemoveInternalServerSocket(talk_base::AsyncSocket* socket);
     81 
     82   // Methods for testing and debuging.
     83   int GetConnectionCount() const;
     84   talk_base::SocketAddressPair GetConnection(int connection) const;
     85   bool HasConnection(const talk_base::SocketAddress& address) const;
     86 
     87  private:
     88   typedef std::vector<talk_base::AsyncPacketSocket*> SocketList;
     89   typedef std::map<talk_base::AsyncSocket*,
     90                    cricket::ProtocolType> ServerSocketMap;
     91   typedef std::map<std::string, RelayServerBinding*> BindingMap;
     92   typedef std::map<talk_base::SocketAddressPair,
     93                    RelayServerConnection*> ConnectionMap;
     94 
     95   talk_base::Thread* thread_;
     96   bool log_bindings_;
     97   SocketList internal_sockets_;
     98   SocketList external_sockets_;
     99   ServerSocketMap server_sockets_;
    100   BindingMap bindings_;
    101   ConnectionMap connections_;
    102 
    103   // Called when a packet is received by the server on one of its sockets.
    104   void OnInternalPacket(talk_base::AsyncPacketSocket* socket,
    105                         const char* bytes, size_t size,
    106                         const talk_base::SocketAddress& remote_addr);
    107   void OnExternalPacket(talk_base::AsyncPacketSocket* socket,
    108                         const char* bytes, size_t size,
    109                         const talk_base::SocketAddress& remote_addr);
    110 
    111   void OnReadEvent(talk_base::AsyncSocket* socket);
    112 
    113   // Processes the relevant STUN request types from the client.
    114   bool HandleStun(const char* bytes, size_t size,
    115                   const talk_base::SocketAddress& remote_addr,
    116                   talk_base::AsyncPacketSocket* socket,
    117                   std::string* username, StunMessage* msg);
    118   void HandleStunAllocate(const char* bytes, size_t size,
    119                           const talk_base::SocketAddressPair& ap,
    120                           talk_base::AsyncPacketSocket* socket);
    121   void HandleStun(RelayServerConnection* int_conn, const char* bytes,
    122                   size_t size);
    123   void HandleStunAllocate(RelayServerConnection* int_conn,
    124                           const StunMessage& msg);
    125   void HandleStunSend(RelayServerConnection* int_conn, const StunMessage& msg);
    126 
    127   // Adds/Removes the a connection or binding.
    128   void AddConnection(RelayServerConnection* conn);
    129   void RemoveConnection(RelayServerConnection* conn);
    130   void RemoveBinding(RelayServerBinding* binding);
    131 
    132   // Handle messages in our worker thread.
    133   void OnMessage(talk_base::Message *pmsg);
    134 
    135   // Called when the timer for checking lifetime times out.
    136   void OnTimeout(RelayServerBinding* binding);
    137 
    138   // Accept connections on this server socket.
    139   void AcceptConnection(talk_base::AsyncSocket* server_socket);
    140 
    141   friend class RelayServerConnection;
    142   friend class RelayServerBinding;
    143 };
    144 
    145 // Maintains information about a connection to the server.  Each connection is
    146 // part of one and only one binding.
    147 class RelayServerConnection {
    148  public:
    149   RelayServerConnection(RelayServerBinding* binding,
    150                         const talk_base::SocketAddressPair& addrs,
    151                         talk_base::AsyncPacketSocket* socket);
    152   ~RelayServerConnection();
    153 
    154   RelayServerBinding* binding() { return binding_; }
    155   talk_base::AsyncPacketSocket* socket() { return socket_; }
    156 
    157   // Returns a pair where the source is the remote address and the destination
    158   // is the local address.
    159   const talk_base::SocketAddressPair& addr_pair() { return addr_pair_; }
    160 
    161   // Sends a packet to the connected client.  If an address is provided, then
    162   // we make sure the internal client receives it, wrapping if necessary.
    163   void Send(const char* data, size_t size);
    164   void Send(const char* data, size_t size,
    165             const talk_base::SocketAddress& ext_addr);
    166 
    167   // Sends a STUN message to the connected client with no wrapping.
    168   void SendStun(const StunMessage& msg);
    169   void SendStunError(const StunMessage& request, int code, const char* desc);
    170 
    171   // A locked connection is one for which we know the intended destination of
    172   // any raw packet received.
    173   bool locked() const { return locked_; }
    174   void Lock();
    175   void Unlock();
    176 
    177   // Records the address that raw packets should be forwarded to (for internal
    178   // packets only; for external, we already know where they go).
    179   const talk_base::SocketAddress& default_destination() const {
    180     return default_dest_;
    181   }
    182   void set_default_destination(const talk_base::SocketAddress& addr) {
    183     default_dest_ = addr;
    184   }
    185 
    186  private:
    187   RelayServerBinding* binding_;
    188   talk_base::SocketAddressPair addr_pair_;
    189   talk_base::AsyncPacketSocket* socket_;
    190   bool locked_;
    191   talk_base::SocketAddress default_dest_;
    192 };
    193 
    194 // Records a set of internal and external connections that we relay between,
    195 // or in other words, that are "bound" together.
    196 class RelayServerBinding : public talk_base::MessageHandler {
    197  public:
    198   RelayServerBinding(
    199       RelayServer* server, const std::string& username,
    200       const std::string& password, uint32 lifetime);
    201   virtual ~RelayServerBinding();
    202 
    203   RelayServer* server() { return server_; }
    204   uint32 lifetime() { return lifetime_; }
    205   const std::string& username() { return username_; }
    206   const std::string& password() { return password_; }
    207   const std::string& magic_cookie() { return magic_cookie_; }
    208 
    209   // Adds/Removes a connection into the binding.
    210   void AddInternalConnection(RelayServerConnection* conn);
    211   void AddExternalConnection(RelayServerConnection* conn);
    212 
    213   // We keep track of the use of each binding.  If we detect that it was not
    214   // used for longer than the lifetime, then we send a signal.
    215   void NoteUsed();
    216   sigslot::signal1<RelayServerBinding*> SignalTimeout;
    217 
    218   // Determines whether the given packet has the magic cookie present (in the
    219   // right place).
    220   bool HasMagicCookie(const char* bytes, size_t size) const;
    221 
    222   // Determines the connection to use to send packets to or from the given
    223   // external address.
    224   RelayServerConnection* GetInternalConnection(
    225       const talk_base::SocketAddress& ext_addr);
    226   RelayServerConnection* GetExternalConnection(
    227       const talk_base::SocketAddress& ext_addr);
    228 
    229   // MessageHandler:
    230   void OnMessage(talk_base::Message *pmsg);
    231 
    232  private:
    233   RelayServer* server_;
    234 
    235   std::string username_;
    236   std::string password_;
    237   std::string magic_cookie_;
    238 
    239   std::vector<RelayServerConnection*> internal_connections_;
    240   std::vector<RelayServerConnection*> external_connections_;
    241 
    242   uint32 lifetime_;
    243   uint32 last_used_;
    244   // TODO: bandwidth
    245 };
    246 
    247 }  // namespace cricket
    248 
    249 #endif  // TALK_P2P_BASE_RELAYSERVER_H_
    250