i2pd/libi2pd/SSUSession.h
Anatolii Cherednichenko 55534ea002 Reformat code
2022-08-30 02:11:28 +03:00

219 lines
8.1 KiB
C++

/*
* Copyright (c) 2013-2022, The PurpleI2P Project
*
* This file is part of Purple i2pd project and licensed under BSD3
*
* See full license text in LICENSE file at top of project tree
*/
#ifndef SSU_SESSION_H__
#define SSU_SESSION_H__
#include <inttypes.h>
#include <set>
#include <memory>
#include "Crypto.h"
#include "I2NPProtocol.h"
#include "TransportSession.h"
#include "SSUData.h"
namespace i2p {
namespace transport {
const uint8_t SSU_HEADER_EXTENDED_OPTIONS_INCLUDED = 0x04;
struct SSUHeader {
uint8_t mac[16];
uint8_t iv[16];
uint8_t flag;
uint8_t time[4];
uint8_t GetPayloadType() const { return flag >> 4; };
bool IsExtendedOptions() const { return flag & SSU_HEADER_EXTENDED_OPTIONS_INCLUDED; };
};
const int SSU_CONNECT_TIMEOUT = 5; // 5 seconds
const int SSU_TERMINATION_TIMEOUT = 330; // 5.5 minutes
const int SSU_CLOCK_SKEW = 60; // in seconds
const int SSU_CLOCK_THRESHOLD = 15; // in seconds, if more we should adjust
const size_t SSU_MAX_I2NP_MESSAGE_SIZE = 32768;
// 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;
// extended options
const uint16_t EXTENDED_OPTIONS_FLAG_REQUEST_RELAY_TAG = 0x0001;
enum SessionState {
eSessionStateUnknown,
eSessionStateIntroduced,
eSessionStateEstablished,
eSessionStateClosed,
eSessionStateFailed
};
enum PeerTestParticipant {
ePeerTestParticipantUnknown = 0,
ePeerTestParticipantAlice1,
ePeerTestParticipantAlice2,
ePeerTestParticipantBob,
ePeerTestParticipantCharlie
};
class SSUServer;
class SSUSession : public TransportSession, public std::enable_shared_from_this<SSUSession> {
public:
SSUSession(SSUServer &server, boost::asio::ip::udp::endpoint &remoteEndpoint,
std::shared_ptr<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 WaitForConnect();
void Introduce(const i2p::data::RouterInfo::Introducer &introducer,
std::shared_ptr<const i2p::data::RouterInfo> to); // Alice to Charlie
void WaitForIntroduction();
void Close();
void Done();
void Failed();
const boost::asio::ip::udp::endpoint &GetRemoteEndpoint() { return m_RemoteEndpoint; };
SSUServer &GetServer() { return m_Server; };
bool IsV6() const { return m_RemoteEndpoint.address().is_v6(); };
void SendI2NPMessages(const std::vector<std::shared_ptr<I2NPMessage> > &msgs);
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; };
const i2p::data::RouterInfo::IntroKey &GetIntroKey() const { return m_IntroKey; };
void FlushData();
void CleanUp(uint64_t ts);
private:
boost::asio::io_service &GetService();
void CreateAESandMacKey(const uint8_t *pubKey);
size_t GetSSUHeaderSize(const uint8_t *buf) const;
void PostI2NPMessages(std::vector<std::shared_ptr<I2NPMessage> > msgs);
void ProcessMessage(uint8_t *buf, size_t len,
const boost::asio::ip::udp::endpoint &senderEndpoint); // call for established session
void ProcessSessionRequest(const uint8_t *buf, size_t len);
void SendSessionRequest();
void SendRelayRequest(const i2p::data::RouterInfo::Introducer &introducer, uint32_t nonce);
void ProcessSessionCreated(uint8_t *buf, size_t len);
void SendSessionCreated(const uint8_t *x, bool sendRelayTag = true);
void ProcessSessionConfirmed(const uint8_t *buf, size_t len);
void SendSessionConfirmed(const uint8_t *y, const uint8_t *ourAddress, size_t ourAddressLen);
void ProcessRelayRequest(const 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(std::shared_ptr<SSUSession> session, const boost::asio::ip::udp::endpoint &from);
void ProcessRelayResponse(const uint8_t *buf, size_t len);
void ProcessRelayIntro(const uint8_t *buf, size_t len);
void Established();
void ScheduleConnectTimer();
void HandleConnectTimer(const boost::system::error_code &ecode);
void ProcessPeerTest(const uint8_t *buf, size_t len, const boost::asio::ip::udp::endpoint &senderEndpoint);
void SendPeerTest(uint32_t nonce, const boost::asio::ip::address &address, uint16_t port,
const uint8_t *introKey, bool toAddress = true, bool sendAddress = true);
void ProcessData(uint8_t *buf, size_t len);
void SendSessionDestroyed();
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 i2p::crypto::AESKey &aesKey,
const uint8_t *iv, const i2p::crypto::MACKey &macKey, uint8_t flag = 0);
void FillHeaderAndEncrypt(uint8_t payloadType, uint8_t *buf, size_t len); // with session key
void FillHeaderAndEncrypt(uint8_t payloadType, uint8_t *in, size_t len, uint8_t *out); // with session key
void Decrypt(uint8_t *buf, size_t len, const i2p::crypto::AESKey &aesKey);
void DecryptSessionKey(uint8_t *buf, size_t len);
bool Validate(uint8_t *buf, size_t len, const i2p::crypto::MACKey &macKey);
void Reset();
static size_t ExtractIPAddressAndPort(const uint8_t *buf, size_t len, boost::asio::ip::address &ip,
uint16_t &port); // returns actual buf size
private:
friend class SSUData; // TODO: change in later
SSUServer &m_Server;
const boost::asio::ip::udp::endpoint m_RemoteEndpoint;
boost::asio::deadline_timer m_ConnectTimer;
bool m_IsPeerTest;
SessionState m_State;
bool m_IsSessionKey;
uint32_t m_RelayTag; // received from peer
uint32_t m_SentRelayTag; // sent by us
i2p::crypto::CBCEncryption m_SessionKeyEncryption;
i2p::crypto::CBCDecryption m_SessionKeyDecryption;
i2p::crypto::AESKey m_SessionKey;
i2p::crypto::MACKey m_MacKey;
i2p::data::RouterInfo::IntroKey m_IntroKey;
SSUData m_Data;
bool m_IsDataReceived;
std::unique_ptr<SignedData> m_SignedData; // we need it for SessionConfirmed only
std::map<uint32_t, std::pair<std::shared_ptr<const i2p::data::RouterInfo>, uint64_t> > m_RelayRequests; // nonce->(Charlie, timestamp)
std::shared_ptr<i2p::crypto::DHKeys> m_DHKeysPair; // X - for client and Y - for server
};
}
}
#endif