external IP detection

RouterContext.cpp

@@ -53,6 +53,13 @@ namespace i2p
 		m_RouterInfo.CreateBuffer ();
 	}	
 
+	void RouterContext::UpdateAddress (const char * host)
+	{
+		for (auto& address : m_RouterInfo.GetAddresses ())
+			address.host = boost::asio::ip::address::from_string (host);	
+		m_RouterInfo.CreateBuffer ();
+	}	
+	
 	void RouterContext::Sign (uint8_t * buf, int len, uint8_t * signature)
 	{
 		CryptoPP::DSA::Signer signer (m_SigningPrivateKey);

RouterContext.h

@@ -28,6 +28,7 @@ namespace i2p
 			void Sign (uint8_t * buf, int len, uint8_t * signature);
 
 			void OverrideNTCPAddress (const char * host, int port); // temporary
+			void UpdateAddress (const char * host);	// called from SSU
 			
 		private:
 

RouterInfo.cpp

@@ -295,6 +295,14 @@ namespace data
 			return m_SupportedTransports & (eNTCPV4 | eNTCPV6);
 	}		
 
+	bool RouterInfo::IsSSU (bool v4only) const
+	{
+		if (v4only)
+			return m_SupportedTransports & eSSUV4;
+		else
+			return m_SupportedTransports & (eSSUV4 | eSSUV6);
+	}
+		
 	RouterInfo::Address * RouterInfo::GetNTCPAddress (bool v4only)
 	{
 		return GetAddress (eTransportNTCP, v4only);

RouterInfo.h

@@ -53,7 +53,7 @@ namespace data
 			const char * GetIdentHashBase64 () const { return m_IdentHashBase64; };
 			const char * GetIdentHashAbbreviation () const { return m_IdentHashAbbreviation; };
 			uint64_t GetTimestamp () const { return m_Timestamp; };
-			const std::vector<Address>& GetAddresses () const { return m_Addresses; };
+			std::vector<Address>& GetAddresses () { return m_Addresses; };
 			Address * GetNTCPAddress (bool v4only = true);
 			Address * GetSSUAddress (bool v4only = true);
 			const RoutingKey& GetRoutingKey () const { return m_RoutingKey; };
@@ -63,6 +63,7 @@ namespace data
 			const char * GetProperty (const char * key) const;
 			bool IsFloodfill () const;
 			bool IsNTCP (bool v4only = true) const;
+			bool IsSSU (bool v4only = true) const;
 			bool IsCompatible (const RouterInfo& other) const { return m_SupportedTransports & other.m_SupportedTransports; };
 			
 			void SetUnreachable (bool unreachable) { m_IsUnreachable = unreachable; }; 

SSU.cpp

@@ -85,7 +85,7 @@ namespace ssu
 				case PAYLOAD_TYPE_TEST:
 					LogPrint ("SSU test received");
 				break;
-				case PAYLOAD_TYPE_SESSION_DESTROY:
+				case PAYLOAD_TYPE_SESSION_DESTROYED:
 					LogPrint ("SSU session destroy received");
 				break;	
 				default:
@@ -129,6 +129,7 @@ namespace ssu
 			boost::asio::ip::address_v4 ourIP (be32toh (*(uint32_t* )(ourAddress)));
 			uint16_t ourPort = be16toh (*(uint16_t *)(ourAddress + 4));
 			LogPrint ("Our external address is ", ourIP.to_string (), ":", ourPort);
+			i2p::context.UpdateAddress (ourIP.to_string ().c_str ());
 			uint32_t relayTag = be32toh (*(uint32_t *)(buf + sizeof (SSUHeader) + 263));
 			SendSessionConfirmed (buf + sizeof (SSUHeader), ourAddress, relayTag);
 			m_State = eSessionStateEstablished;
@@ -357,6 +358,11 @@ namespace ssu
 		SendSessionRequest ();
 	}
 
+	void SSUSession::Close ()
+	{
+		SendSesionDestroyed ();
+	}	
+	
 	void SSUSession::SendI2NPMessage (I2NPMessage * msg)
 	{
 		// TODO:
@@ -445,7 +451,7 @@ namespace ssu
 
 	void SSUSession::SendMsgAck (uint32_t msgID)
 	{
-		uint8_t buf[48]; // actual length is 44 = 37 + 7 but pad it to multiple of 16
+		uint8_t buf[48 + 18]; // actual length is 44 = 37 + 7 but pad it to multiple of 16
 		uint8_t iv[16];
 		uint8_t * payload = buf + sizeof (SSUHeader);
 		*payload = DATA_FLAG_EXPLICIT_ACKS_INCLUDED; // flag
@@ -463,6 +469,16 @@ namespace ssu
 		m_Server->Send (buf, 48, m_RemoteEndpoint);
 	}
 
+	void SSUSession::SendSesionDestroyed ()
+	{
+		uint8_t buf[48 + 18], iv[16];
+		CryptoPP::RandomNumberGenerator& rnd = i2p::context.GetRandomNumberGenerator ();
+		rnd.GenerateBlock (iv, 16); // random iv
+		// encrypt message with session key
+		FillHeaderAndEncrypt (PAYLOAD_TYPE_SESSION_DESTROYED, buf, 48, m_SessionKey, iv, m_MacKey);
+		m_Server->Send (buf, 48, m_RemoteEndpoint);
+	}	
+	
 	SSUServer::SSUServer (boost::asio::io_service& service, int port):
 		m_Endpoint (boost::asio::ip::udp::v4 (), port), m_Socket (service, m_Endpoint)
 	{
@@ -546,6 +562,26 @@ namespace ssu
 		}
 		return session;
 	}
+
+	void SSUServer::DeleteSession (SSUSession * session)
+	{
+		if (session)
+		{
+			session->Close ();
+			m_Sessions.erase (session->GetRemoteEndpoint ());
+			delete session;
+		}	
+	}	
+
+	void SSUServer::DeleteAllSessions ()
+	{
+		for (auto it: m_Sessions)
+		{
+			it.second->Close ();
+			delete it.second;			
+		}	
+		m_Sessions.clear ();
+	}	
 }
 }
 

SSU.h

@@ -35,7 +35,7 @@ namespace ssu
 	const uint8_t PAYLOAD_TYPE_RELAY_INTRO = 5;
 	const uint8_t PAYLOAD_TYPE_DATA = 6;
 	const uint8_t PAYLOAD_TYPE_TEST = 7;
-	const uint8_t PAYLOAD_TYPE_SESSION_DESTROY = 8;
+	const uint8_t PAYLOAD_TYPE_SESSION_DESTROYED = 8;
 
 	// data flags
 	const uint8_t DATA_FLAG_EXTENDED_DATA_INCLUDED = 0x02;
@@ -67,6 +67,8 @@ namespace ssu
 			void ProcessNextMessage (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& senderEndpoint);		
 
 			void Connect ();
+			void Close ();
+			boost::asio::ip::udp::endpoint& GetRemoteEndpoint () { return m_RemoteEndpoint; };
 			void SendI2NPMessage (I2NPMessage * msg);
 
 		private:
@@ -82,6 +84,7 @@ namespace ssu
 			void SendSessionConfirmed (const uint8_t * y, const uint8_t * ourAddress, uint32_t relayTag);
 			void ProcessData (uint8_t * buf, size_t len);	
 			void SendMsgAck (uint32_t msgID);
+			void SendSesionDestroyed ();
 			
 			bool ProcessIntroKeyEncryptedMessage (uint8_t expectedPayloadType, i2p::data::RouterInfo& r, uint8_t * buf, size_t len);
 			void FillHeaderAndEncrypt (uint8_t payloadType, uint8_t * buf, size_t len, uint8_t * aesKey, uint8_t * iv, uint8_t * macKey);
@@ -109,6 +112,8 @@ namespace ssu
 			void Start ();
 			void Stop ();
 			SSUSession * GetSession (i2p::data::RouterInfo * router);
+			void DeleteSession (SSUSession * session);
+			void DeleteAllSessions ();
 			
 			const boost::asio::ip::udp::endpoint& GetEndpoint () const { return m_Endpoint; };			
 			void Send (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& to);

Transports.cpp

@@ -25,6 +25,7 @@ namespace i2p
 	{
 		m_IsRunning = true;
 		m_Thread = new std::thread (std::bind (&Transports::Run, this));
+		m_Timer = new boost::asio::deadline_timer (m_Service);
 		// create acceptors
 		auto addresses = context.GetRouterInfo ().GetAddresses ();
 		for (auto& address : addresses)
@@ -38,9 +39,11 @@ namespace i2p
 				auto conn = new i2p::ntcp::NTCPServerConnection (m_Service);
 				m_NTCPAcceptor->async_accept(conn->GetSocket (), boost::bind (&Transports::HandleAccept, this, 
 					conn, boost::asio::placeholders::error));
-			}	
+			// temporary always run SSU server
+			// TODO: uncomment following lines later	
+			/*}	
 			else if (address.transportStyle == RouterInfo::eTransportSSU)
-			{
+			{*/
 				if (!m_SSUServer)
 				{	
 					m_SSUServer = new i2p::ssu::SSUServer (m_Service, address.port);
@@ -51,6 +54,9 @@ namespace i2p
 					LogPrint ("SSU server already exists");
 			}
 		}	
+
+		// TODO: do it for SSU only
+		DetectExternalIP ();
 	}
 		
 	void Transports::Stop ()
@@ -60,6 +66,9 @@ namespace i2p
 		m_NTCPSessions.clear ();
 		delete m_NTCPAcceptor;
 		
+		m_Timer->cancel ();
+		delete m_Timer;
+		
 		if (m_SSUServer)
 		{
 			m_SSUServer->Stop ();
@@ -173,4 +182,30 @@ namespace i2p
 		else
 			LogPrint ("Session not found"); 
 	}	
+
+	void Transports::DetectExternalIP ()
+	{
+		for (int i = 0; i < 5; i ++)
+		{
+			auto router = i2p::data::netdb.GetRandomRouter ();
+			if (router && router->IsSSU () && m_SSUServer)
+				m_SSUServer->GetSession (const_cast<i2p::data::RouterInfo *>(router)); //TODO	
+		}	
+		if (m_Timer)
+		{	
+			m_Timer->expires_from_now (boost::posix_time::seconds(5)); // 5 seconds
+			m_Timer->async_wait (boost::bind (&Transports::HandleTimer, this, boost::asio::placeholders::error));
+		}	
+	}
+		
+	void Transports::HandleTimer (const boost::system::error_code& ecode)
+	{
+		if (ecode != boost::asio::error::operation_aborted)
+		{
+			// end of external IP detection
+			if (m_SSUServer)
+				 m_SSUServer->DeleteAllSessions ();
+		}	
+	}	
+		
 }

Transports.h

@@ -39,6 +39,9 @@ namespace i2p
 			void HandleAccept (i2p::ntcp::NTCPServerConnection * conn, const boost::system::error_code& error);
 			void PostMessage (const i2p::data::IdentHash& ident, i2p::I2NPMessage * msg);
 
+			void DetectExternalIP ();
+			void HandleTimer (const boost::system::error_code& ecode);
+			
 		private:
 
 			bool m_IsRunning;
@@ -49,6 +52,7 @@ namespace i2p
 
 			std::map<i2p::data::IdentHash, i2p::ntcp::NTCPSession *> m_NTCPSessions;
 			i2p::ssu::SSUServer * m_SSUServer;
+			boost::asio::deadline_timer * m_Timer;
 
 		public: