#ifndef SSU_H__ #define SSU_H__ #include #include #include #include #include #include "I2PEndian.h" namespace i2p { namespace ssu { #pragma pack(1) struct SSUHeader { uint8_t mac[16]; uint8_t iv[16]; uint8_t flag; uint32_t time; }; #pragma pack() const int SSU_MTU = 1484; // 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_TEST = 7; enum SessionState { eSessionStateUnknown, eSessionStateRequestSent, eSessionStateRequestReceived, eSessionStateCreatedSent, eSessionStateCreatedReceived, eSessionStateConfirmedSent, eSessionStateConfirmedReceived, eSessionStateEstablised }; class SSUSession { public: SSUSession (); void ProcessNextMessage (uint8_t * buf, size_t len); private: void Authenticate (uint8_t * buf, size_t len, uint8_t * aesKey, uint8_t * iv, uint8_t * macKey); private: SessionState m_State; CryptoPP::CBC_Mode::Encryption m_Encryption; }; class SSUServer { public: SSUServer (boost::asio::io_service& service, int port); ~SSUServer (); void Start (); void Stop (); private: void Receive (); void HandleReceivedFrom (const boost::system::error_code& ecode, std::size_t bytes_transferred); private: boost::asio::ip::udp::socket m_Socket; boost::asio::ip::udp::endpoint m_SenderEndpoint; uint8_t m_ReceiveBuffer[SSU_MTU]; std::map m_Sessions; }; } } #endif