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28 #ifndef TALK_BASE_NATSERVER_H_
29 #define TALK_BASE_NATSERVER_H_
34 #include "talk/base/asyncudpsocket.h"
35 #include "talk/base/socketaddresspair.h"
36 #include "talk/base/thread.h"
37 #include "talk/base/socketfactory.h"
38 #include "talk/base/nattypes.h"
42 // Change how routes (socketaddress pairs) are compared based on the type of
43 // NAT. The NAT server maintains a hashtable of the routes that it knows
44 // about. So these affect which routes are treated the same.
46 explicit RouteCmp(NAT* nat);
47 size_t operator()(const SocketAddressPair& r) const;
49 const SocketAddressPair& r1, const SocketAddressPair& r2) const;
54 // Changes how addresses are compared based on the filtering rules of the NAT.
56 explicit AddrCmp(NAT* nat);
57 size_t operator()(const SocketAddress& r) const;
58 bool operator()(const SocketAddress& r1, const SocketAddress& r2) const;
64 // Implements the NAT device. It listens for packets on the internal network,
65 // translates them, and sends them out over the external network.
67 const int NAT_SERVER_PORT = 4237;
69 class NATServer : public sigslot::has_slots<> {
72 NATType type, SocketFactory* internal, const SocketAddress& internal_addr,
73 SocketFactory* external, const SocketAddress& external_ip);
76 SocketAddress internal_address() const {
77 return server_socket_->GetLocalAddress();
80 // Packets received on one of the networks.
81 void OnInternalPacket(AsyncPacketSocket* socket, const char* buf,
82 size_t size, const SocketAddress& addr);
83 void OnExternalPacket(AsyncPacketSocket* socket, const char* buf,
84 size_t size, const SocketAddress& remote_addr);
87 typedef std::set<SocketAddress, AddrCmp> AddressSet;
89 /* Records a translation and the associated external socket. */
91 TransEntry(const SocketAddressPair& r, AsyncUDPSocket* s, NAT* nat);
94 void WhitelistInsert(const SocketAddress& addr);
95 bool WhitelistContains(const SocketAddress& ext_addr);
97 SocketAddressPair route;
98 AsyncUDPSocket* socket;
99 AddressSet* whitelist;
100 CriticalSection crit_;
103 typedef std::map<SocketAddressPair, TransEntry*, RouteCmp> InternalMap;
104 typedef std::map<SocketAddress, TransEntry*> ExternalMap;
106 /* Creates a new entry that translates the given route. */
107 void Translate(const SocketAddressPair& route);
109 /* Determines whether the NAT would filter out a packet from this address. */
110 bool ShouldFilterOut(TransEntry* entry, const SocketAddress& ext_addr);
113 SocketFactory* internal_;
114 SocketFactory* external_;
115 SocketAddress external_ip_;
116 AsyncUDPSocket* server_socket_;
117 AsyncSocket* tcp_server_socket_;
118 InternalMap* int_map_;
119 ExternalMap* ext_map_;
120 DISALLOW_EVIL_CONSTRUCTORS(NATServer);
123 } // namespace talk_base
125 #endif // TALK_BASE_NATSERVER_H_