split SSU to SSU and SSUSession

SSUSession.h

@@ -0,0 +1,143 @@
+#ifndef SSU_SESSION_H__
+#define SSU_SESSION_H__
+
+#include <inttypes.h>
+#include <set>
+#include <list>
+#include <boost/asio.hpp>
+#include "aes.h"
+#include "I2NPProtocol.h"
+#include "TransportSession.h"
+#include "SSUData.h"
+
+namespace i2p
+{
+namespace transport
+{
+#pragma pack(1)
+	struct SSUHeader
+	{
+		uint8_t mac[16];
+		uint8_t iv[16];
+		uint8_t flag;
+		uint32_t time;	
+
+		uint8_t GetPayloadType () const { return flag >> 4; };
+	};
+#pragma pack()
+
+	const int SSU_CONNECT_TIMEOUT = 5; // 5 seconds
+	const int SSU_TERMINATION_TIMEOUT = 330; // 5.5 minutes
+
+	// payload types (4 bits)
+	const uint8_t PAYLOAD_TYPE_SESSION_REQUEST = 0;
+	const uint8_t PAYLOAD_TYPE_SESSION_CREATED = 1;
+	const uint8_t PAYLOAD_TYPE_SESSION_CONFIRMED = 2;
+	const uint8_t PAYLOAD_TYPE_RELAY_REQUEST = 3;
+	const uint8_t PAYLOAD_TYPE_RELAY_RESPONSE = 4;
+	const uint8_t PAYLOAD_TYPE_RELAY_INTRO = 5;
+	const uint8_t PAYLOAD_TYPE_DATA = 6;
+	const uint8_t PAYLOAD_TYPE_PEER_TEST = 7;
+	const uint8_t PAYLOAD_TYPE_SESSION_DESTROYED = 8;
+
+	enum SessionState
+	{
+		eSessionStateUnknown,	
+		eSessionStateIntroduced,
+		eSessionStateEstablished,
+		eSessionStateFailed
+	};	
+
+	class SSUServer;
+	class SSUSession: public TransportSession
+	{
+		public:
+
+			SSUSession (SSUServer& server, boost::asio::ip::udp::endpoint& remoteEndpoint,
+				const i2p::data::RouterInfo * router = nullptr, bool peerTest = false);
+			void ProcessNextMessage (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& senderEndpoint);		
+			~SSUSession ();
+			
+			void Connect ();
+			void Introduce (uint32_t iTag, const uint8_t * iKey);
+			void WaitForIntroduction ();
+			void Close ();
+			boost::asio::ip::udp::endpoint& GetRemoteEndpoint () { return m_RemoteEndpoint; };
+			bool IsV6 () const { return m_RemoteEndpoint.address ().is_v6 (); };
+			void SendI2NPMessage (I2NPMessage * msg);
+			void SendPeerTest (); // Alice			
+
+			SessionState GetState () const  { return m_State; };
+			size_t GetNumSentBytes () const { return m_NumSentBytes; };
+			size_t GetNumReceivedBytes () const { return m_NumReceivedBytes; };
+			
+			void SendKeepAlive ();	
+			uint32_t GetRelayTag () const { return m_RelayTag; };	
+			uint32_t GetCreationTime () const { return m_CreationTime; };
+
+		private:
+
+			void CreateAESandMacKey (const uint8_t * pubKey); 
+
+			void PostI2NPMessage (I2NPMessage * msg);
+			void ProcessMessage (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& senderEndpoint); // call for established session
+			void ProcessSessionRequest (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& senderEndpoint);
+			void SendSessionRequest ();
+			void SendRelayRequest (uint32_t iTag, const uint8_t * iKey);
+			void ProcessSessionCreated (uint8_t * buf, size_t len);
+			void SendSessionCreated (const uint8_t * x);
+			void ProcessSessionConfirmed (uint8_t * buf, size_t len);
+			void SendSessionConfirmed (const uint8_t * y, const uint8_t * ourAddress, size_t ourAddressLen);
+			void ProcessRelayRequest (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& from);
+			void SendRelayResponse (uint32_t nonce, const boost::asio::ip::udp::endpoint& from,
+				const uint8_t * introKey, const boost::asio::ip::udp::endpoint& to);
+			void SendRelayIntro (SSUSession * session, const boost::asio::ip::udp::endpoint& from);
+			void ProcessRelayResponse (uint8_t * buf, size_t len);
+			void ProcessRelayIntro (uint8_t * buf, size_t len);
+			void Established ();
+			void Failed ();
+			void ScheduleConnectTimer ();
+			void HandleConnectTimer (const boost::system::error_code& ecode);
+			void ProcessPeerTest (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& senderEndpoint);
+			void SendPeerTest (uint32_t nonce, uint32_t address, uint16_t port, const uint8_t * introKey, bool toAddress = true); 
+			void ProcessData (uint8_t * buf, size_t len);		
+			void SendSesionDestroyed ();
+			void Send (uint8_t type, const uint8_t * payload, size_t len); // with session key
+			void Send (const uint8_t * buf, size_t size); 
+			
+			void FillHeaderAndEncrypt (uint8_t payloadType, uint8_t * buf, size_t len, const uint8_t * aesKey, const uint8_t * iv, const uint8_t * macKey);
+			void FillHeaderAndEncrypt (uint8_t payloadType, uint8_t * buf, size_t len); // with session key 
+			void Decrypt (uint8_t * buf, size_t len, const uint8_t * aesKey);
+			void DecryptSessionKey (uint8_t * buf, size_t len);
+			bool Validate (uint8_t * buf, size_t len, const uint8_t * macKey);			
+			const uint8_t * GetIntroKey () const; 
+
+			void ScheduleTermination ();
+			void HandleTerminationTimer (const boost::system::error_code& ecode);
+
+		private:
+	
+			friend class SSUData; // TODO: change in later
+			SSUServer& m_Server;
+			boost::asio::ip::udp::endpoint m_RemoteEndpoint;
+			boost::asio::deadline_timer m_Timer;
+			bool m_PeerTest;
+			SessionState m_State;
+			bool m_IsSessionKey;
+			uint32_t m_RelayTag;	
+			std::set<uint32_t> m_PeerTestNonces;
+			i2p::crypto::CBCEncryption m_SessionKeyEncryption;
+			i2p::crypto::CBCDecryption m_SessionKeyDecryption;
+			uint8_t m_SessionKey[32], m_MacKey[32];
+			std::list<i2p::I2NPMessage *> m_DelayedMessages;
+			SSUData m_Data;
+			size_t m_NumSentBytes, m_NumReceivedBytes;
+			uint32_t m_CreationTime; // seconds since epoch
+	};
+
+
+}
+}
+
+#endif
+