i2pd/libi2pd/NTCP2.cpp
Anatolii Cherednichenko 55534ea002 Reformat code
2022-08-30 02:11:28 +03:00

1586 lines
80 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
*
*/
#include <openssl/rand.h>
#include <openssl/sha.h>
#include <openssl/hmac.h>
#include <stdlib.h>
#include <vector>
#include "Log.h"
#include "I2PEndian.h"
#include "Crypto.h"
#include "Siphash.h"
#include "RouterContext.h"
#include "Transports.h"
#include "NetDb.hpp"
#include "NTCP2.h"
#include "HTTP.h"
#include "util.h"
#if defined(__linux__) && !defined(_NETINET_IN_H)
#include <linux/in6.h>
#endif
namespace i2p {
namespace transport {
NTCP2Establisher::NTCP2Establisher() :
m_SessionConfirmedBuffer(nullptr) {
}
NTCP2Establisher::~NTCP2Establisher() {
delete[] m_SessionConfirmedBuffer;
}
void
NTCP2Establisher::KeyDerivationFunction1(const uint8_t *pub, i2p::crypto::X25519Keys &priv, const uint8_t *rs,
const uint8_t *epub) {
i2p::crypto::InitNoiseXKState(*this, rs);
// h = SHA256(h || epub)
MixHash(epub, 32);
// x25519 between pub and priv
uint8_t inputKeyMaterial[32];
priv.Agree(pub, inputKeyMaterial);
MixKey(inputKeyMaterial);
}
void NTCP2Establisher::KDF1Alice() {
KeyDerivationFunction1(m_RemoteStaticKey, *m_EphemeralKeys, m_RemoteStaticKey, GetPub());
}
void NTCP2Establisher::KDF1Bob() {
KeyDerivationFunction1(GetRemotePub(), i2p::context.GetNTCP2StaticKeys(),
i2p::context.GetNTCP2StaticPublicKey(), GetRemotePub());
}
void NTCP2Establisher::KeyDerivationFunction2(const uint8_t *sessionRequest, size_t sessionRequestLen,
const uint8_t *epub) {
MixHash(sessionRequest + 32, 32); // encrypted payload
int paddingLength = sessionRequestLen - 64;
if (paddingLength > 0)
MixHash(sessionRequest + 64, paddingLength);
MixHash(epub, 32);
// x25519 between remote pub and ephemaral priv
uint8_t inputKeyMaterial[32];
m_EphemeralKeys->Agree(GetRemotePub(), inputKeyMaterial);
MixKey(inputKeyMaterial);
}
void NTCP2Establisher::KDF2Alice() {
KeyDerivationFunction2(m_SessionRequestBuffer, m_SessionRequestBufferLen, GetRemotePub());
}
void NTCP2Establisher::KDF2Bob() {
KeyDerivationFunction2(m_SessionRequestBuffer, m_SessionRequestBufferLen, GetPub());
}
void NTCP2Establisher::KDF3Alice() {
uint8_t inputKeyMaterial[32];
i2p::context.GetNTCP2StaticKeys().Agree(GetRemotePub(), inputKeyMaterial);
MixKey(inputKeyMaterial);
}
void NTCP2Establisher::KDF3Bob() {
uint8_t inputKeyMaterial[32];
m_EphemeralKeys->Agree(m_RemoteStaticKey, inputKeyMaterial);
MixKey(inputKeyMaterial);
}
void NTCP2Establisher::CreateEphemeralKey() {
m_EphemeralKeys = i2p::transport::transports.GetNextX25519KeysPair();
}
void NTCP2Establisher::CreateSessionRequestMessage() {
// create buffer and fill padding
auto paddingLength =
rand() % (NTCP2_SESSION_REQUEST_MAX_SIZE - 64); // message length doesn't exceed 287 bytes
m_SessionRequestBufferLen = paddingLength + 64;
RAND_bytes(m_SessionRequestBuffer + 64, paddingLength);
// encrypt X
i2p::crypto::CBCEncryption encryption;
encryption.SetKey(m_RemoteIdentHash);
encryption.SetIV(m_IV);
encryption.Encrypt(GetPub(), 32, m_SessionRequestBuffer); // X
encryption.GetIV(m_IV); // save IV for SessionCreated
// encryption key for next block
KDF1Alice();
// fill options
uint8_t options[32]; // actual options size is 16 bytes
memset(options, 0, 16);
options[0] = i2p::context.GetNetID(); // network ID
options[1] = 2; // ver
htobe16buf(options + 2, paddingLength); // padLen
// m3p2Len
auto bufLen = i2p::context.GetRouterInfo().GetBufferLen();
m3p2Len = bufLen + 4 + 16; // (RI header + RI + MAC for now) TODO: implement options
htobe16buf(options + 4, m3p2Len);
// fill m3p2 payload (RouterInfo block)
m_SessionConfirmedBuffer = new uint8_t[m3p2Len + 48]; // m3p1 is 48 bytes
uint8_t *m3p2 = m_SessionConfirmedBuffer + 48;
m3p2[0] = eNTCP2BlkRouterInfo; // block
htobe16buf(m3p2 + 1, bufLen + 1); // flag + RI
m3p2[3] = 0; // flag
memcpy(m3p2 + 4, i2p::context.GetRouterInfo().GetBuffer(),
bufLen); // TODO: own RI should be protected by mutex
// 2 bytes reserved
htobe32buf(options + 8, i2p::util::GetSecondsSinceEpoch()); // tsA
// 4 bytes reserved
// sign and encrypt options, use m_H as AD
uint8_t nonce[12];
memset(nonce, 0, 12); // set nonce to zero
i2p::crypto::AEADChaCha20Poly1305(options, 16, GetH(), 32, GetK(), nonce, m_SessionRequestBuffer + 32, 32,
true); // encrypt
}
void NTCP2Establisher::CreateSessionCreatedMessage() {
auto paddingLen = rand() % (NTCP2_SESSION_CREATED_MAX_SIZE - 64);
m_SessionCreatedBufferLen = paddingLen + 64;
RAND_bytes(m_SessionCreatedBuffer + 64, paddingLen);
// encrypt Y
i2p::crypto::CBCEncryption encryption;
encryption.SetKey(i2p::context.GetIdentHash());
encryption.SetIV(m_IV);
encryption.Encrypt(GetPub(), 32, m_SessionCreatedBuffer); // Y
// encryption key for next block (m_K)
KDF2Bob();
uint8_t options[16];
memset(options, 0, 16);
htobe16buf(options + 2, paddingLen); // padLen
htobe32buf(options + 8, i2p::util::GetSecondsSinceEpoch()); // tsB
// sign and encrypt options, use m_H as AD
uint8_t nonce[12];
memset(nonce, 0, 12); // set nonce to zero
i2p::crypto::AEADChaCha20Poly1305(options, 16, GetH(), 32, GetK(), nonce, m_SessionCreatedBuffer + 32, 32,
true); // encrypt
}
void NTCP2Establisher::CreateSessionConfirmedMessagePart1(const uint8_t *nonce) {
// update AD
MixHash(m_SessionCreatedBuffer + 32, 32); // encrypted payload
int paddingLength = m_SessionCreatedBufferLen - 64;
if (paddingLength > 0)
MixHash(m_SessionCreatedBuffer + 64, paddingLength);
// part1 48 bytes
i2p::crypto::AEADChaCha20Poly1305(i2p::context.GetNTCP2StaticPublicKey(), 32, GetH(), 32, GetK(), nonce,
m_SessionConfirmedBuffer, 48, true); // encrypt
}
void NTCP2Establisher::CreateSessionConfirmedMessagePart2(const uint8_t *nonce) {
// part 2
// update AD again
MixHash(m_SessionConfirmedBuffer, 48);
// encrypt m3p2, it must be filled in SessionRequest
KDF3Alice();
uint8_t *m3p2 = m_SessionConfirmedBuffer + 48;
i2p::crypto::AEADChaCha20Poly1305(m3p2, m3p2Len - 16, GetH(), 32, GetK(), nonce, m3p2, m3p2Len,
true); // encrypt
// update h again
MixHash(m3p2, m3p2Len); //h = SHA256(h || ciphertext)
}
bool NTCP2Establisher::ProcessSessionRequestMessage(uint16_t &paddingLen, bool &clockSkew) {
clockSkew = false;
// decrypt X
i2p::crypto::CBCDecryption decryption;
decryption.SetKey(i2p::context.GetIdentHash());
decryption.SetIV(i2p::context.GetNTCP2IV());
decryption.Decrypt(m_SessionRequestBuffer, 32, GetRemotePub());
decryption.GetIV(m_IV); // save IV for SessionCreated
// decryption key for next block
KDF1Bob();
// verify MAC and decrypt options block (32 bytes), use m_H as AD
uint8_t nonce[12], options[16];
memset(nonce, 0, 12); // set nonce to zero
if (i2p::crypto::AEADChaCha20Poly1305(m_SessionRequestBuffer + 32, 16, GetH(), 32, GetK(), nonce, options,
16, false)) // decrypt
{
// options
if (options[0] && options[0] != i2p::context.GetNetID()) {
LogPrint(eLogWarning, "NTCP2: SessionRequest networkID ", (int) options[0], " mismatch. Expected ",
i2p::context.GetNetID());
return false;
}
if (options[1] == 2) // ver is always 2
{
paddingLen = bufbe16toh(options + 2);
m_SessionRequestBufferLen = paddingLen + 64;
m3p2Len = bufbe16toh(options + 4);
if (m3p2Len < 16) {
LogPrint(eLogWarning, "NTCP2: SessionRequest m3p2len=", m3p2Len, " is too short");
return false;
}
// check timestamp
auto ts = i2p::util::GetSecondsSinceEpoch();
uint32_t tsA = bufbe32toh(options + 8);
if (tsA < ts - NTCP2_CLOCK_SKEW || tsA > ts + NTCP2_CLOCK_SKEW) {
LogPrint(eLogWarning, "NTCP2: SessionRequest time difference ", (int) (ts - tsA),
" exceeds clock skew");
clockSkew = true;
// we send SessionCreate to let Alice know our time and then close session
}
} else {
LogPrint(eLogWarning, "NTCP2: SessionRequest version mismatch ", (int) options[1]);
return false;
}
} else {
LogPrint(eLogWarning, "NTCP2: SessionRequest AEAD verification failed ");
return false;
}
return true;
}
bool NTCP2Establisher::ProcessSessionCreatedMessage(uint16_t &paddingLen) {
m_SessionCreatedBufferLen = 64;
// decrypt Y
i2p::crypto::CBCDecryption decryption;
decryption.SetKey(m_RemoteIdentHash);
decryption.SetIV(m_IV);
decryption.Decrypt(m_SessionCreatedBuffer, 32, GetRemotePub());
// decryption key for next block (m_K)
KDF2Alice();
// decrypt and verify MAC
uint8_t payload[16];
uint8_t nonce[12];
memset(nonce, 0, 12); // set nonce to zero
if (i2p::crypto::AEADChaCha20Poly1305(m_SessionCreatedBuffer + 32, 16, GetH(), 32, GetK(), nonce, payload,
16, false)) // decrypt
{
// options
paddingLen = bufbe16toh(payload + 2);
// check timestamp
auto ts = i2p::util::GetSecondsSinceEpoch();
uint32_t tsB = bufbe32toh(payload + 8);
if (tsB < ts - NTCP2_CLOCK_SKEW || tsB > ts + NTCP2_CLOCK_SKEW) {
LogPrint(eLogWarning, "NTCP2: SessionCreated time difference ", (int) (ts - tsB),
" exceeds clock skew");
return false;
}
} else {
LogPrint(eLogWarning, "NTCP2: SessionCreated AEAD verification failed ");
return false;
}
return true;
}
bool NTCP2Establisher::ProcessSessionConfirmedMessagePart1(const uint8_t *nonce) {
// update AD
MixHash(m_SessionCreatedBuffer + 32, 32); // encrypted payload
int paddingLength = m_SessionCreatedBufferLen - 64;
if (paddingLength > 0)
MixHash(m_SessionCreatedBuffer + 64, paddingLength);
if (!i2p::crypto::AEADChaCha20Poly1305(m_SessionConfirmedBuffer, 32, GetH(), 32, GetK(), nonce,
m_RemoteStaticKey, 32, false)) // decrypt S
{
LogPrint(eLogWarning, "NTCP2: SessionConfirmed Part1 AEAD verification failed ");
return false;
}
return true;
}
bool NTCP2Establisher::ProcessSessionConfirmedMessagePart2(const uint8_t *nonce, uint8_t *m3p2Buf) {
// update AD again
MixHash(m_SessionConfirmedBuffer, 48);
KDF3Bob();
if (i2p::crypto::AEADChaCha20Poly1305(m_SessionConfirmedBuffer + 48, m3p2Len - 16, GetH(), 32, GetK(),
nonce, m3p2Buf, m3p2Len - 16, false)) // decrypt
// caclulate new h again for KDF data
MixHash(m_SessionConfirmedBuffer + 48, m3p2Len); // h = SHA256(h || ciphertext)
else {
LogPrint(eLogWarning, "NTCP2: SessionConfirmed Part2 AEAD verification failed ");
return false;
}
return true;
}
NTCP2Session::NTCP2Session(NTCP2Server &server, std::shared_ptr<const i2p::data::RouterInfo> in_RemoteRouter,
std::shared_ptr<const i2p::data::RouterInfo::Address> addr) :
TransportSession(in_RemoteRouter, NTCP2_ESTABLISH_TIMEOUT),
m_Server(server), m_Socket(m_Server.GetService()),
m_IsEstablished(false), m_IsTerminated(false),
m_Establisher(new NTCP2Establisher),
#if OPENSSL_SIPHASH
m_SendMDCtx(nullptr), m_ReceiveMDCtx (nullptr),
#else
m_SendSipKey(nullptr), m_ReceiveSipKey(nullptr),
#endif
m_NextReceivedLen(0), m_NextReceivedBuffer(nullptr), m_NextSendBuffer(nullptr),
m_NextReceivedBufferSize(0), m_ReceiveSequenceNumber(0), m_SendSequenceNumber(0),
m_IsSending(false), m_IsReceiving(false), m_NextPaddingSize(16) {
if (in_RemoteRouter) // Alice
{
m_Establisher->m_RemoteIdentHash = GetRemoteIdentity()->GetIdentHash();
if (addr) {
memcpy(m_Establisher->m_RemoteStaticKey, addr->s, 32);
memcpy(m_Establisher->m_IV, addr->i, 16);
m_RemoteEndpoint = boost::asio::ip::tcp::endpoint(addr->host, addr->port);
} else
LogPrint(eLogWarning, "NTCP2: Missing NTCP2 address");
}
m_NextRouterInfoResendTime = i2p::util::GetSecondsSinceEpoch() + NTCP2_ROUTERINFO_RESEND_INTERVAL +
rand() % NTCP2_ROUTERINFO_RESEND_INTERVAL_THRESHOLD;
}
NTCP2Session::~NTCP2Session() {
delete[] m_NextReceivedBuffer;
delete[] m_NextSendBuffer;
#if OPENSSL_SIPHASH
if (m_SendMDCtx) EVP_MD_CTX_destroy (m_SendMDCtx);
if (m_ReceiveMDCtx) EVP_MD_CTX_destroy (m_ReceiveMDCtx);
#endif
}
void NTCP2Session::Terminate() {
if (!m_IsTerminated) {
m_IsTerminated = true;
m_IsEstablished = false;
boost::system::error_code ec;
m_Socket.shutdown(boost::asio::ip::tcp::socket::shutdown_both, ec);
if (ec)
LogPrint(eLogDebug, "NTCP2: Couldn't shutdown socket: ", ec.message());
m_Socket.close();
transports.PeerDisconnected(shared_from_this());
m_Server.RemoveNTCP2Session(shared_from_this());
m_SendQueue.clear();
LogPrint(eLogDebug, "NTCP2: Session terminated");
}
}
void NTCP2Session::TerminateByTimeout() {
SendTerminationAndTerminate(eNTCP2IdleTimeout);
}
void NTCP2Session::Done() {
m_Server.GetService().post(std::bind(&NTCP2Session::Terminate, shared_from_this()));
}
void NTCP2Session::Established() {
m_IsEstablished = true;
m_Establisher.reset(nullptr);
SetTerminationTimeout(NTCP2_TERMINATION_TIMEOUT);
transports.PeerConnected(shared_from_this());
}
void NTCP2Session::CreateNonce(uint64_t seqn, uint8_t *nonce) {
memset(nonce, 0, 4);
htole64buf(nonce + 4, seqn);
}
void NTCP2Session::CreateNextReceivedBuffer(size_t size) {
if (m_NextReceivedBuffer) {
if (size <= m_NextReceivedBufferSize)
return; // buffer is good, do nothing
else
delete[] m_NextReceivedBuffer;
}
m_NextReceivedBuffer = new uint8_t[size];
m_NextReceivedBufferSize = size;
}
void NTCP2Session::DeleteNextReceiveBuffer(uint64_t ts) {
if (m_NextReceivedBuffer && !m_IsReceiving &&
ts > m_LastActivityTimestamp + NTCP2_RECEIVE_BUFFER_DELETION_TIMEOUT) {
delete[] m_NextReceivedBuffer;
m_NextReceivedBuffer = nullptr;
m_NextReceivedBufferSize = 0;
}
}
void NTCP2Session::KeyDerivationFunctionDataPhase() {
uint8_t k[64];
i2p::crypto::HKDF(m_Establisher->GetCK(), nullptr, 0, "", k); // k_ab, k_ba = HKDF(ck, zerolen)
memcpy(m_Kab, k, 32);
memcpy(m_Kba, k + 32, 32);
uint8_t master[32];
i2p::crypto::HKDF(m_Establisher->GetCK(), nullptr, 0, "ask", master,
32); // ask_master = HKDF(ck, zerolen, info="ask")
uint8_t h[39];
memcpy(h, m_Establisher->GetH(), 32);
memcpy(h + 32, "siphash", 7);
i2p::crypto::HKDF(master, h, 39, "", master, 32); // sip_master = HKDF(ask_master, h || "siphash")
i2p::crypto::HKDF(master, nullptr, 0, "", k); // sipkeys_ab, sipkeys_ba = HKDF(sip_master, zerolen)
memcpy(m_Sipkeysab, k, 32);
memcpy(m_Sipkeysba, k + 32, 32);
}
void NTCP2Session::SendSessionRequest() {
m_Establisher->CreateSessionRequestMessage();
// send message
boost::asio::async_write(m_Socket, boost::asio::buffer(m_Establisher->m_SessionRequestBuffer,
m_Establisher->m_SessionRequestBufferLen),
boost::asio::transfer_all(),
std::bind(&NTCP2Session::HandleSessionRequestSent, shared_from_this(),
std::placeholders::_1, std::placeholders::_2));
}
void
NTCP2Session::HandleSessionRequestSent(const boost::system::error_code &ecode, std::size_t bytes_transferred) {
(void) bytes_transferred;
if (ecode) {
LogPrint(eLogWarning, "NTCP2: Couldn't send SessionRequest message: ", ecode.message());
Terminate();
} else {
// we receive first 64 bytes (32 Y, and 32 ChaCha/Poly frame) first
boost::asio::async_read(m_Socket, boost::asio::buffer(m_Establisher->m_SessionCreatedBuffer, 64),
boost::asio::transfer_all(),
std::bind(&NTCP2Session::HandleSessionCreatedReceived, shared_from_this(),
std::placeholders::_1, std::placeholders::_2));
}
}
void NTCP2Session::HandleSessionRequestReceived(const boost::system::error_code &ecode,
std::size_t bytes_transferred) {
(void) bytes_transferred;
if (ecode) {
LogPrint(eLogWarning, "NTCP2: SessionRequest read error: ", ecode.message());
Terminate();
} else {
LogPrint(eLogDebug, "NTCP2: SessionRequest received ", bytes_transferred);
uint16_t paddingLen = 0;
bool clockSkew = false;
if (m_Establisher->ProcessSessionRequestMessage(paddingLen, clockSkew)) {
if (clockSkew) {
// we don't care about padding, send SessionCreated and close session
SendSessionCreated();
m_Server.GetService().post(std::bind(&NTCP2Session::Terminate, shared_from_this()));
} else if (paddingLen > 0) {
if (paddingLen <= NTCP2_SESSION_REQUEST_MAX_SIZE - 64) // session request is 287 bytes max
{
boost::asio::async_read(m_Socket,
boost::asio::buffer(m_Establisher->m_SessionRequestBuffer + 64,
paddingLen), boost::asio::transfer_all(),
std::bind(&NTCP2Session::HandleSessionRequestPaddingReceived,
shared_from_this(), std::placeholders::_1,
std::placeholders::_2));
} else {
LogPrint(eLogWarning, "NTCP2: SessionRequest padding length ", (int) paddingLen,
" is too long");
Terminate();
}
} else
SendSessionCreated();
} else
Terminate();
}
}
void NTCP2Session::HandleSessionRequestPaddingReceived(const boost::system::error_code &ecode,
std::size_t bytes_transferred) {
if (ecode) {
LogPrint(eLogWarning, "NTCP2: SessionRequest padding read error: ", ecode.message());
Terminate();
} else
SendSessionCreated();
}
void NTCP2Session::SendSessionCreated() {
m_Establisher->CreateSessionCreatedMessage();
// send message
boost::asio::async_write(m_Socket, boost::asio::buffer(m_Establisher->m_SessionCreatedBuffer,
m_Establisher->m_SessionCreatedBufferLen),
boost::asio::transfer_all(),
std::bind(&NTCP2Session::HandleSessionCreatedSent, shared_from_this(),
std::placeholders::_1, std::placeholders::_2));
}
void NTCP2Session::HandleSessionCreatedReceived(const boost::system::error_code &ecode,
std::size_t bytes_transferred) {
if (ecode) {
LogPrint(eLogWarning, "NTCP2: SessionCreated read error: ", ecode.message());
Terminate();
} else {
LogPrint(eLogDebug, "NTCP2: SessionCreated received ", bytes_transferred);
uint16_t paddingLen = 0;
if (m_Establisher->ProcessSessionCreatedMessage(paddingLen)) {
if (paddingLen > 0) {
if (paddingLen <= NTCP2_SESSION_CREATED_MAX_SIZE - 64) // session created is 287 bytes max
{
boost::asio::async_read(m_Socket,
boost::asio::buffer(m_Establisher->m_SessionCreatedBuffer + 64,
paddingLen), boost::asio::transfer_all(),
std::bind(&NTCP2Session::HandleSessionCreatedPaddingReceived,
shared_from_this(), std::placeholders::_1,
std::placeholders::_2));
} else {
LogPrint(eLogWarning, "NTCP2: SessionCreated padding length ", (int) paddingLen,
" is too long");
Terminate();
}
} else
SendSessionConfirmed();
} else
Terminate();
}
}
void NTCP2Session::HandleSessionCreatedPaddingReceived(const boost::system::error_code &ecode,
std::size_t bytes_transferred) {
if (ecode) {
LogPrint(eLogWarning, "NTCP2: SessionCreated padding read error: ", ecode.message());
Terminate();
} else {
m_Establisher->m_SessionCreatedBufferLen += bytes_transferred;
SendSessionConfirmed();
}
}
void NTCP2Session::SendSessionConfirmed() {
uint8_t nonce[12];
CreateNonce(1, nonce); // set nonce to 1
m_Establisher->CreateSessionConfirmedMessagePart1(nonce);
memset(nonce, 0, 12); // set nonce back to 0
m_Establisher->CreateSessionConfirmedMessagePart2(nonce);
// send message
boost::asio::async_write(m_Socket, boost::asio::buffer(m_Establisher->m_SessionConfirmedBuffer,
m_Establisher->m3p2Len + 48),
boost::asio::transfer_all(),
std::bind(&NTCP2Session::HandleSessionConfirmedSent, shared_from_this(),
std::placeholders::_1, std::placeholders::_2));
}
void NTCP2Session::HandleSessionConfirmedSent(const boost::system::error_code &ecode,
std::size_t bytes_transferred) {
(void) bytes_transferred;
if (ecode) {
LogPrint(eLogWarning, "NTCP2: Couldn't send SessionConfirmed message: ", ecode.message());
Terminate();
} else {
LogPrint(eLogDebug, "NTCP2: SessionConfirmed sent");
KeyDerivationFunctionDataPhase();
// Alice data phase keys
m_SendKey = m_Kab;
m_ReceiveKey = m_Kba;
SetSipKeys(m_Sipkeysab, m_Sipkeysba);
memcpy(m_ReceiveIV.buf, m_Sipkeysba + 16, 8);
memcpy(m_SendIV.buf, m_Sipkeysab + 16, 8);
Established();
ReceiveLength();
// TODO: remove
// m_SendQueue.push_back (CreateDeliveryStatusMsg (1));
// SendQueue ();
}
}
void
NTCP2Session::HandleSessionCreatedSent(const boost::system::error_code &ecode, std::size_t bytes_transferred) {
(void) bytes_transferred;
if (ecode) {
LogPrint(eLogWarning, "NTCP2: Couldn't send SessionCreated message: ", ecode.message());
Terminate();
} else {
LogPrint(eLogDebug, "NTCP2: SessionCreated sent");
m_Establisher->m_SessionConfirmedBuffer = new uint8_t[m_Establisher->m3p2Len + 48];
boost::asio::async_read(m_Socket, boost::asio::buffer(m_Establisher->m_SessionConfirmedBuffer,
m_Establisher->m3p2Len + 48),
boost::asio::transfer_all(),
std::bind(&NTCP2Session::HandleSessionConfirmedReceived, shared_from_this(),
std::placeholders::_1, std::placeholders::_2));
}
}
void NTCP2Session::HandleSessionConfirmedReceived(const boost::system::error_code &ecode,
std::size_t bytes_transferred) {
if (ecode) {
LogPrint(eLogWarning, "NTCP2: SessionConfirmed read error: ", ecode.message());
Terminate();
} else {
LogPrint(eLogDebug, "NTCP2: SessionConfirmed received");
// part 1
uint8_t nonce[12];
CreateNonce(1, nonce);
if (m_Establisher->ProcessSessionConfirmedMessagePart1(nonce)) {
// part 2
std::vector<uint8_t> buf(m_Establisher->m3p2Len - 16); // -MAC
memset(nonce, 0, 12); // set nonce to 0 again
if (m_Establisher->ProcessSessionConfirmedMessagePart2(nonce, buf.data())) {
KeyDerivationFunctionDataPhase();
// Bob data phase keys
m_SendKey = m_Kba;
m_ReceiveKey = m_Kab;
SetSipKeys(m_Sipkeysba, m_Sipkeysab);
memcpy(m_ReceiveIV.buf, m_Sipkeysab + 16, 8);
memcpy(m_SendIV.buf, m_Sipkeysba + 16, 8);
// payload
// process RI
if (buf[0] != eNTCP2BlkRouterInfo) {
LogPrint(eLogWarning, "NTCP2: Unexpected block ", (int) buf[0], " in SessionConfirmed");
Terminate();
return;
}
auto size = bufbe16toh(buf.data() + 1);
if (size > buf.size() - 3) {
LogPrint(eLogError, "NTCP2: Unexpected RouterInfo size ", size, " in SessionConfirmed");
Terminate();
return;
}
// TODO: check flag
i2p::data::RouterInfo ri(buf.data() + 4,
size - 1); // 1 byte block type + 2 bytes size + 1 byte flag
if (ri.IsUnreachable()) {
LogPrint(eLogError, "NTCP2: Signature verification failed in SessionConfirmed");
SendTerminationAndTerminate(eNTCP2RouterInfoSignatureVerificationFail);
return;
}
if (i2p::util::GetMillisecondsSinceEpoch() >
ri.GetTimestamp() + i2p::data::NETDB_MIN_EXPIRATION_TIMEOUT * 1000LL) // 90 minutes
{
LogPrint(eLogError, "NTCP2: RouterInfo is too old in SessionConfirmed");
SendTerminationAndTerminate(eNTCP2Message3Error);
return;
}
auto addr = ri.GetNTCP2AddressWithStaticKey(m_Establisher->m_RemoteStaticKey);
if (!addr) {
LogPrint(eLogError, "NTCP2: No NTCP2 address with static key found in SessionConfirmed");
Terminate();
return;
}
i2p::data::netdb.PostI2NPMsg(CreateI2NPMessage(eI2NPDummyMsg, buf.data() + 3,
size)); // TODO: should insert ri and not parse it twice
// TODO: process options
// ready to communicate
auto existing = i2p::data::netdb.FindRouter(
ri.GetRouterIdentity()->GetIdentHash()); // check if exists already
SetRemoteIdentity(existing ? existing->GetRouterIdentity() : ri.GetRouterIdentity());
if (m_Server.AddNTCP2Session(shared_from_this(), true)) {
Established();
ReceiveLength();
} else
Terminate();
} else
Terminate();
} else
Terminate();
}
}
void NTCP2Session::SetSipKeys(const uint8_t *sendSipKey, const uint8_t *receiveSipKey) {
#if OPENSSL_SIPHASH
EVP_PKEY * sipKey = EVP_PKEY_new_raw_private_key (EVP_PKEY_SIPHASH, nullptr, sendSipKey, 16);
m_SendMDCtx = EVP_MD_CTX_create ();
EVP_PKEY_CTX *ctx = nullptr;
EVP_DigestSignInit (m_SendMDCtx, &ctx, nullptr, nullptr, sipKey);
EVP_PKEY_CTX_ctrl (ctx, -1, EVP_PKEY_OP_SIGNCTX, EVP_PKEY_CTRL_SET_DIGEST_SIZE, 8, nullptr);
EVP_PKEY_free (sipKey);
sipKey = EVP_PKEY_new_raw_private_key (EVP_PKEY_SIPHASH, nullptr, receiveSipKey, 16);
m_ReceiveMDCtx = EVP_MD_CTX_create ();
ctx = nullptr;
EVP_DigestSignInit (m_ReceiveMDCtx, &ctx, NULL, NULL, sipKey);
EVP_PKEY_CTX_ctrl (ctx, -1, EVP_PKEY_OP_SIGNCTX, EVP_PKEY_CTRL_SET_DIGEST_SIZE, 8, nullptr);
EVP_PKEY_free (sipKey);
#else
m_SendSipKey = sendSipKey;
m_ReceiveSipKey = receiveSipKey;
#endif
}
void NTCP2Session::ClientLogin() {
m_Establisher->CreateEphemeralKey();
SendSessionRequest();
}
void NTCP2Session::ServerLogin() {
m_Establisher->CreateEphemeralKey();
boost::asio::async_read(m_Socket, boost::asio::buffer(m_Establisher->m_SessionRequestBuffer, 64),
boost::asio::transfer_all(),
std::bind(&NTCP2Session::HandleSessionRequestReceived, shared_from_this(),
std::placeholders::_1, std::placeholders::_2));
}
void NTCP2Session::ReceiveLength() {
if (IsTerminated()) return;
#ifdef __linux__
const int one = 1;
setsockopt(m_Socket.native_handle(), IPPROTO_TCP, TCP_QUICKACK, &one, sizeof(one));
#endif
boost::asio::async_read(m_Socket, boost::asio::buffer(&m_NextReceivedLen, 2), boost::asio::transfer_all(),
std::bind(&NTCP2Session::HandleReceivedLength, shared_from_this(),
std::placeholders::_1, std::placeholders::_2));
}
void NTCP2Session::HandleReceivedLength(const boost::system::error_code &ecode, std::size_t bytes_transferred) {
if (ecode) {
if (ecode != boost::asio::error::operation_aborted)
LogPrint(eLogWarning, "NTCP2: Receive length read error: ", ecode.message());
Terminate();
} else {
#if OPENSSL_SIPHASH
EVP_DigestSignInit (m_ReceiveMDCtx, nullptr, nullptr, nullptr, nullptr);
EVP_DigestSignUpdate (m_ReceiveMDCtx, m_ReceiveIV.buf, 8);
size_t l = 8;
EVP_DigestSignFinal (m_ReceiveMDCtx, m_ReceiveIV.buf, &l);
#else
i2p::crypto::Siphash<8>(m_ReceiveIV.buf, m_ReceiveIV.buf, 8, m_ReceiveSipKey);
#endif
// m_NextReceivedLen comes from the network in BigEndian
m_NextReceivedLen = be16toh(m_NextReceivedLen) ^ le16toh (m_ReceiveIV.key);
LogPrint(eLogDebug, "NTCP2: Received length ", m_NextReceivedLen);
if (m_NextReceivedLen >= 16) {
CreateNextReceivedBuffer(m_NextReceivedLen);
boost::system::error_code ec;
size_t moreBytes = m_Socket.available(ec);
if (!ec && moreBytes >= m_NextReceivedLen) {
// read and process message immediately if available
moreBytes = boost::asio::read(m_Socket,
boost::asio::buffer(m_NextReceivedBuffer, m_NextReceivedLen),
boost::asio::transfer_all(), ec);
HandleReceived(ec, moreBytes);
} else
Receive();
} else {
LogPrint(eLogError, "NTCP2: Received length ", m_NextReceivedLen, " is too short");
Terminate();
}
}
}
void NTCP2Session::Receive() {
if (IsTerminated()) return;
#ifdef __linux__
const int one = 1;
setsockopt(m_Socket.native_handle(), IPPROTO_TCP, TCP_QUICKACK, &one, sizeof(one));
#endif
m_IsReceiving = true;
boost::asio::async_read(m_Socket, boost::asio::buffer(m_NextReceivedBuffer, m_NextReceivedLen),
boost::asio::transfer_all(),
std::bind(&NTCP2Session::HandleReceived, shared_from_this(), std::placeholders::_1,
std::placeholders::_2));
}
void NTCP2Session::HandleReceived(const boost::system::error_code &ecode, std::size_t bytes_transferred) {
if (ecode) {
if (ecode != boost::asio::error::operation_aborted)
LogPrint(eLogWarning, "NTCP2: Receive read error: ", ecode.message());
Terminate();
} else {
m_LastActivityTimestamp = i2p::util::GetSecondsSinceEpoch();
m_NumReceivedBytes += bytes_transferred + 2; // + length
i2p::transport::transports.UpdateReceivedBytes(bytes_transferred);
uint8_t nonce[12];
CreateNonce(m_ReceiveSequenceNumber, nonce);
m_ReceiveSequenceNumber++;
if (i2p::crypto::AEADChaCha20Poly1305(m_NextReceivedBuffer, m_NextReceivedLen - 16, nullptr, 0,
m_ReceiveKey, nonce, m_NextReceivedBuffer, m_NextReceivedLen,
false)) {
LogPrint(eLogDebug, "NTCP2: Received message decrypted");
ProcessNextFrame(m_NextReceivedBuffer, m_NextReceivedLen - 16);
m_IsReceiving = false;
ReceiveLength();
} else {
LogPrint(eLogWarning, "NTCP2: Received AEAD verification failed ");
SendTerminationAndTerminate(eNTCP2DataPhaseAEADFailure);
}
}
}
void NTCP2Session::ProcessNextFrame(const uint8_t *frame, size_t len) {
size_t offset = 0;
while (offset < len) {
uint8_t blk = frame[offset];
offset++;
auto size = bufbe16toh(frame + offset);
offset += 2;
LogPrint(eLogDebug, "NTCP2: Block type ", (int) blk, " of size ", size);
if (size > len) {
LogPrint(eLogError, "NTCP2: Unexpected block length ", size);
break;
}
switch (blk) {
case eNTCP2BlkDateTime:
LogPrint(eLogDebug, "NTCP2: Datetime");
break;
case eNTCP2BlkOptions:
LogPrint(eLogDebug, "NTCP2: Options");
break;
case eNTCP2BlkRouterInfo: {
LogPrint(eLogDebug, "NTCP2: RouterInfo flag=", (int) frame[offset]);
i2p::data::netdb.PostI2NPMsg(CreateI2NPMessage(eI2NPDummyMsg, frame + offset, size));
break;
}
case eNTCP2BlkI2NPMessage: {
LogPrint(eLogDebug, "NTCP2: I2NP");
if (size > I2NP_MAX_MESSAGE_SIZE) {
LogPrint(eLogError, "NTCP2: I2NP block is too long ", size);
break;
}
auto nextMsg = (frame[offset] == eI2NPTunnelData) ? NewI2NPTunnelMessage(true) : NewI2NPMessage(
size);
nextMsg->len = nextMsg->offset + size + 7; // 7 more bytes for full I2NP header
if (nextMsg->len <= nextMsg->maxLen) {
memcpy(nextMsg->GetNTCP2Header(), frame + offset, size);
nextMsg->FromNTCP2();
m_Handler.PutNextMessage(std::move(nextMsg));
} else
LogPrint(eLogError, "NTCP2: I2NP block is too long for I2NP message");
break;
}
case eNTCP2BlkTermination:
if (size >= 9) {
LogPrint(eLogDebug, "NTCP2: Termination. reason=", (int) (frame[offset + 8]));
Terminate();
} else
LogPrint(eLogWarning, "NTCP2: Unexpected termination block size ", size);
break;
case eNTCP2BlkPadding:
LogPrint(eLogDebug, "NTCP2: Padding");
break;
default:
LogPrint(eLogWarning, "NTCP2: Unknown block type ", (int) blk);
}
offset += size;
}
m_Handler.Flush();
}
void NTCP2Session::SetNextSentFrameLength(size_t frameLen, uint8_t *lengthBuf) {
#if OPENSSL_SIPHASH
EVP_DigestSignInit (m_SendMDCtx, nullptr, nullptr, nullptr, nullptr);
EVP_DigestSignUpdate (m_SendMDCtx, m_SendIV.buf, 8);
size_t l = 8;
EVP_DigestSignFinal (m_SendMDCtx, m_SendIV.buf, &l);
#else
i2p::crypto::Siphash<8>(m_SendIV.buf, m_SendIV.buf, 8, m_SendSipKey);
#endif
// length must be in BigEndian
htobe16buf(lengthBuf, frameLen ^ le16toh (m_SendIV.key));
LogPrint(eLogDebug, "NTCP2: Sent length ", frameLen);
}
void NTCP2Session::SendI2NPMsgs(std::vector<std::shared_ptr<I2NPMessage> > &msgs) {
if (msgs.empty() || IsTerminated()) return;
size_t totalLen = 0;
std::vector<std::pair<uint8_t *, size_t> > encryptBufs;
std::vector<boost::asio::const_buffer> bufs;
std::shared_ptr<I2NPMessage> first;
uint8_t *macBuf = nullptr;
for (auto &it: msgs) {
it->ToNTCP2();
auto buf = it->GetNTCP2Header();
auto len = it->GetNTCP2Length();
// block header
buf -= 3;
buf[0] = eNTCP2BlkI2NPMessage; // blk
htobe16buf(buf + 1, len); // size
len += 3;
totalLen += len;
encryptBufs.push_back({buf, len});
if (&it == &msgs.front()) // first message
{
// allocate two bytes for length
buf -= 2;
len += 2;
first = it;
}
if (&it == &msgs.back() && it->len + 16 < it->maxLen) // last message
{
// if it's long enough we add padding and MAC to it
// create padding block
auto paddingLen = CreatePaddingBlock(totalLen, buf + len, it->maxLen - it->len - 16);
if (paddingLen) {
encryptBufs.push_back({buf + len, paddingLen});
len += paddingLen;
totalLen += paddingLen;
}
macBuf = buf + len;
// allocate 16 bytes for MAC
len += 16;
}
bufs.push_back(boost::asio::buffer(buf, len));
}
if (!macBuf) // last block was not enough for MAC
{
// allocate send buffer
m_NextSendBuffer = new uint8_t[287]; // can be any size > 16, we just allocate 287 frequently
// create padding block
auto paddingLen = CreatePaddingBlock(totalLen, m_NextSendBuffer, 287 - 16);
// and padding block to encrypt and send
if (paddingLen)
encryptBufs.push_back({m_NextSendBuffer, paddingLen});
bufs.push_back(boost::asio::buffer(m_NextSendBuffer, paddingLen + 16));
macBuf = m_NextSendBuffer + paddingLen;
totalLen += paddingLen;
}
uint8_t nonce[12];
CreateNonce(m_SendSequenceNumber, nonce);
m_SendSequenceNumber++;
i2p::crypto::AEADChaCha20Poly1305Encrypt(encryptBufs, m_SendKey, nonce, macBuf); // encrypt buffers
SetNextSentFrameLength(totalLen + 16, first->GetNTCP2Header() - 5); // frame length right before first block
// send buffers
m_IsSending = true;
boost::asio::async_write(m_Socket, bufs, boost::asio::transfer_all(),
std::bind(&NTCP2Session::HandleI2NPMsgsSent, shared_from_this(),
std::placeholders::_1, std::placeholders::_2, msgs));
}
void NTCP2Session::HandleI2NPMsgsSent(const boost::system::error_code &ecode, std::size_t bytes_transferred,
std::vector<std::shared_ptr<I2NPMessage> > msgs) {
HandleNextFrameSent(ecode, bytes_transferred);
// msgs get destroyed here
}
void NTCP2Session::EncryptAndSendNextBuffer(size_t payloadLen) {
if (IsTerminated()) {
delete[] m_NextSendBuffer;
m_NextSendBuffer = nullptr;
return;
}
// encrypt
uint8_t nonce[12];
CreateNonce(m_SendSequenceNumber, nonce);
m_SendSequenceNumber++;
i2p::crypto::AEADChaCha20Poly1305Encrypt({{m_NextSendBuffer + 2, payloadLen}}, m_SendKey, nonce,
m_NextSendBuffer + payloadLen + 2);
SetNextSentFrameLength(payloadLen + 16, m_NextSendBuffer);
// send
m_IsSending = true;
boost::asio::async_write(m_Socket, boost::asio::buffer(m_NextSendBuffer, payloadLen + 16 + 2),
boost::asio::transfer_all(),
std::bind(&NTCP2Session::HandleNextFrameSent, shared_from_this(),
std::placeholders::_1, std::placeholders::_2));
}
void NTCP2Session::HandleNextFrameSent(const boost::system::error_code &ecode, std::size_t bytes_transferred) {
m_IsSending = false;
delete[] m_NextSendBuffer;
m_NextSendBuffer = nullptr;
if (ecode) {
if (ecode != boost::asio::error::operation_aborted)
LogPrint(eLogWarning, "NTCP2: Couldn't send frame ", ecode.message());
Terminate();
} else {
m_LastActivityTimestamp = i2p::util::GetSecondsSinceEpoch();
m_NumSentBytes += bytes_transferred;
i2p::transport::transports.UpdateSentBytes(bytes_transferred);
LogPrint(eLogDebug, "NTCP2: Next frame sent ", bytes_transferred);
if (m_LastActivityTimestamp > m_NextRouterInfoResendTime) {
m_NextRouterInfoResendTime += NTCP2_ROUTERINFO_RESEND_INTERVAL +
rand() % NTCP2_ROUTERINFO_RESEND_INTERVAL_THRESHOLD;
SendRouterInfo();
} else
SendQueue();
}
}
void NTCP2Session::SendQueue() {
if (!m_SendQueue.empty()) {
std::vector<std::shared_ptr<I2NPMessage> > msgs;
size_t s = 0;
while (!m_SendQueue.empty()) {
auto msg = m_SendQueue.front();
size_t len = msg->GetNTCP2Length();
if (s + len + 3 <= NTCP2_UNENCRYPTED_FRAME_MAX_SIZE) // 3 bytes block header
{
msgs.push_back(msg);
s += (len + 3);
m_SendQueue.pop_front();
} else if (len + 3 > NTCP2_UNENCRYPTED_FRAME_MAX_SIZE) {
LogPrint(eLogError, "NTCP2: I2NP message of size ", len, " can't be sent. Dropped");
m_SendQueue.pop_front();
} else
break;
}
SendI2NPMsgs(msgs);
}
}
size_t NTCP2Session::CreatePaddingBlock(size_t msgLen, uint8_t *buf, size_t len) {
if (len < 3) return 0;
len -= 3;
if (msgLen < 256) msgLen = 256; // for short message padding should not be always zero
size_t paddingSize = (msgLen * NTCP2_MAX_PADDING_RATIO) / 100;
if (msgLen + paddingSize + 3 > NTCP2_UNENCRYPTED_FRAME_MAX_SIZE) paddingSize =
NTCP2_UNENCRYPTED_FRAME_MAX_SIZE -
msgLen - 3;
if (paddingSize > len) paddingSize = len;
if (paddingSize) {
if (m_NextPaddingSize >= 16) {
RAND_bytes((uint8_t *) m_PaddingSizes, sizeof(m_PaddingSizes));
m_NextPaddingSize = 0;
}
paddingSize = m_PaddingSizes[m_NextPaddingSize++] % paddingSize;
}
buf[0] = eNTCP2BlkPadding; // blk
htobe16buf(buf + 1, paddingSize); // size
memset(buf + 3, 0, paddingSize);
return paddingSize + 3;
}
void NTCP2Session::SendRouterInfo() {
if (!IsEstablished()) return;
auto riLen = i2p::context.GetRouterInfo().GetBufferLen();
size_t payloadLen = riLen + 4; // 3 bytes block header + 1 byte RI flag
m_NextSendBuffer = new uint8_t[payloadLen + 16 + 2 + 64]; // up to 64 bytes padding
m_NextSendBuffer[2] = eNTCP2BlkRouterInfo;
htobe16buf(m_NextSendBuffer + 3, riLen + 1); // size
m_NextSendBuffer[5] = 0; // flag
memcpy(m_NextSendBuffer + 6, i2p::context.GetRouterInfo().GetBuffer(), riLen);
// padding block
auto paddingSize = CreatePaddingBlock(payloadLen, m_NextSendBuffer + 2 + payloadLen, 64);
payloadLen += paddingSize;
// encrypt and send
EncryptAndSendNextBuffer(payloadLen);
}
void NTCP2Session::SendTermination(NTCP2TerminationReason reason) {
if (!m_SendKey ||
#if OPENSSL_SIPHASH
!m_SendMDCtx
#else
!m_SendSipKey
#endif
)
return;
m_NextSendBuffer = new uint8_t[49]; // 49 = 12 bytes message + 16 bytes MAC + 2 bytes size + up to 19 padding block
// termination block
m_NextSendBuffer[2] = eNTCP2BlkTermination;
m_NextSendBuffer[3] = 0;
m_NextSendBuffer[4] = 9; // 9 bytes block size
htobe64buf(m_NextSendBuffer + 5, m_ReceiveSequenceNumber);
m_NextSendBuffer[13] = (uint8_t) reason;
// padding block
auto paddingSize = CreatePaddingBlock(12, m_NextSendBuffer + 14, 19);
// encrypt and send
EncryptAndSendNextBuffer(paddingSize + 12);
}
void NTCP2Session::SendTerminationAndTerminate(NTCP2TerminationReason reason) {
SendTermination(reason);
m_Server.GetService().post(
std::bind(&NTCP2Session::Terminate, shared_from_this())); // let termination message go
}
void NTCP2Session::SendI2NPMessages(const std::vector<std::shared_ptr<I2NPMessage> > &msgs) {
m_Server.GetService().post(std::bind(&NTCP2Session::PostI2NPMessages, shared_from_this(), msgs));
}
void NTCP2Session::PostI2NPMessages(std::vector<std::shared_ptr<I2NPMessage> > msgs) {
if (m_IsTerminated) return;
for (auto it: msgs)
m_SendQueue.push_back(it);
if (!m_IsSending)
SendQueue();
else if (m_SendQueue.size() > NTCP2_MAX_OUTGOING_QUEUE_SIZE) {
LogPrint(eLogWarning, "NTCP2: Outgoing messages queue size to ",
GetIdentHashBase64(), " exceeds ", NTCP2_MAX_OUTGOING_QUEUE_SIZE);
Terminate();
}
}
void NTCP2Session::SendLocalRouterInfo(bool update) {
if (update || !IsOutgoing()) // we send it in SessionConfirmed for ougoing session
m_Server.GetService().post(std::bind(&NTCP2Session::SendRouterInfo, shared_from_this()));
}
NTCP2Server::NTCP2Server() :
RunnableServiceWithWork("NTCP2"), m_TerminationTimer(GetService()),
m_ProxyType(eNoProxy), m_Resolver(GetService()) {
}
NTCP2Server::~NTCP2Server() {
Stop();
}
void NTCP2Server::Start() {
if (!IsRunning()) {
StartIOService();
if (UsingProxy()) {
LogPrint(eLogInfo, "NTCP2: Using proxy to connect to peers");
// TODO: resolve proxy until it is resolved
boost::asio::ip::tcp::resolver::query q(m_ProxyAddress, std::to_string(m_ProxyPort));
boost::system::error_code e;
auto itr = m_Resolver.resolve(q, e);
if (e)
LogPrint(eLogError, "NTCP2: Failed to resolve proxy ", e.message());
else {
m_ProxyEndpoint.reset(new boost::asio::ip::tcp::endpoint(*itr));
if (m_ProxyEndpoint)
LogPrint(eLogDebug, "NTCP2: m_ProxyEndpoint ", *m_ProxyEndpoint);
}
} else
LogPrint(eLogInfo, "NTCP2: Proxy is not used");
// start acceptors
auto &addresses = context.GetRouterInfo().GetAddresses();
for (const auto &address: addresses) {
if (!address) continue;
if (address->IsPublishedNTCP2() && address->port) {
if (address->IsV4()) {
try {
auto ep = m_Address4 ? boost::asio::ip::tcp::endpoint(m_Address4->address(),
address->port) :
boost::asio::ip::tcp::endpoint(boost::asio::ip::tcp::v4(), address->port);
m_NTCP2Acceptor.reset(new boost::asio::ip::tcp::acceptor(GetService(), ep));
}
catch (std::exception &ex) {
LogPrint(eLogError, "NTCP2: Failed to bind to v4 port ", address->port, ex.what());
ThrowFatal("Unable to start IPv4 NTCP2 transport at port ", address->port, ": ",
ex.what());
continue;
}
LogPrint(eLogInfo, "NTCP2: Start listening v4 TCP port ", address->port);
auto conn = std::make_shared<NTCP2Session>(*this);
m_NTCP2Acceptor->async_accept(conn->GetSocket(),
std::bind(&NTCP2Server::HandleAccept, this, conn,
std::placeholders::_1));
} else if (address->IsV6() && (context.SupportsV6() || context.SupportsMesh())) {
m_NTCP2V6Acceptor.reset(new boost::asio::ip::tcp::acceptor(GetService()));
try {
m_NTCP2V6Acceptor->open(boost::asio::ip::tcp::v6());
m_NTCP2V6Acceptor->set_option(boost::asio::ip::v6_only(true));
m_NTCP2V6Acceptor->set_option(boost::asio::socket_base::reuse_address(true));
#if defined(__linux__) && !defined(_NETINET_IN_H)
if (!m_Address6 && !m_YggdrasilAddress) // only if not binded to address
{
// Set preference to use public IPv6 address -- tested on linux, not works on windows, and not tested on others
#if (BOOST_VERSION >= 105500)
typedef boost::asio::detail::socket_option::integer<BOOST_ASIO_OS_DEF(IPPROTO_IPV6), IPV6_ADDR_PREFERENCES> ipv6PreferAddr;
#else
typedef boost::asio::detail::socket_option::integer<IPPROTO_IPV6, IPV6_ADDR_PREFERENCES> ipv6PreferAddr;
#endif
m_NTCP2V6Acceptor->set_option (ipv6PreferAddr(IPV6_PREFER_SRC_PUBLIC | IPV6_PREFER_SRC_HOME | IPV6_PREFER_SRC_NONCGA));
}
#endif
auto ep = boost::asio::ip::tcp::endpoint(boost::asio::ip::tcp::v6(), address->port);
if (m_Address6 && !context.SupportsMesh())
ep = boost::asio::ip::tcp::endpoint(m_Address6->address(), address->port);
else if (m_YggdrasilAddress && !context.SupportsV6())
ep = boost::asio::ip::tcp::endpoint(m_YggdrasilAddress->address(), address->port);
m_NTCP2V6Acceptor->bind(ep);
m_NTCP2V6Acceptor->listen();
LogPrint(eLogInfo, "NTCP2: Start listening v6 TCP port ", address->port);
auto conn = std::make_shared<NTCP2Session>(*this);
m_NTCP2V6Acceptor->async_accept(conn->GetSocket(),
std::bind(&NTCP2Server::HandleAcceptV6, this, conn,
std::placeholders::_1));
}
catch (std::exception &ex) {
LogPrint(eLogError, "NTCP2: Failed to bind to v6 port ", address->port, ": ",
ex.what());
ThrowFatal("Unable to start IPv6 NTCP2 transport at port ", address->port, ": ",
ex.what());
continue;
}
}
}
}
ScheduleTermination();
}
}
void NTCP2Server::Stop() {
{
// we have to copy it because Terminate changes m_NTCP2Sessions
auto ntcpSessions = m_NTCP2Sessions;
for (auto &it: ntcpSessions)
it.second->Terminate();
for (auto &it: m_PendingIncomingSessions)
it->Terminate();
}
m_NTCP2Sessions.clear();
if (IsRunning()) {
m_TerminationTimer.cancel();
m_ProxyEndpoint = nullptr;
}
StopIOService();
}
bool NTCP2Server::AddNTCP2Session(std::shared_ptr<NTCP2Session> session, bool incoming) {
if (!session) return false;
if (incoming)
m_PendingIncomingSessions.remove(session);
if (!session->GetRemoteIdentity()) return false;
auto &ident = session->GetRemoteIdentity()->GetIdentHash();
auto it = m_NTCP2Sessions.find(ident);
if (it != m_NTCP2Sessions.end()) {
LogPrint(eLogWarning, "NTCP2: Session to ", ident.ToBase64(), " already exists");
if (incoming)
// replace by new session
it->second->Terminate();
else
return false;
}
m_NTCP2Sessions.insert(std::make_pair(ident, session));
return true;
}
void NTCP2Server::RemoveNTCP2Session(std::shared_ptr<NTCP2Session> session) {
if (session && session->GetRemoteIdentity())
m_NTCP2Sessions.erase(session->GetRemoteIdentity()->GetIdentHash());
}
std::shared_ptr<NTCP2Session> NTCP2Server::FindNTCP2Session(const i2p::data::IdentHash &ident) {
auto it = m_NTCP2Sessions.find(ident);
if (it != m_NTCP2Sessions.end())
return it->second;
return nullptr;
}
void NTCP2Server::Connect(std::shared_ptr<NTCP2Session> conn) {
if (!conn || conn->GetRemoteEndpoint().address().is_unspecified()) {
LogPrint(eLogError, "NTCP2: Can't connect to unspecified address");
return;
}
LogPrint(eLogDebug, "NTCP2: Connecting to ", conn->GetRemoteEndpoint());
GetService().post([this, conn]() {
if (this->AddNTCP2Session(conn)) {
auto timer = std::make_shared<boost::asio::deadline_timer>(GetService());
auto timeout = NTCP2_CONNECT_TIMEOUT * 5;
conn->SetTerminationTimeout(timeout * 2);
timer->expires_from_now(boost::posix_time::seconds(timeout));
timer->async_wait([conn, timeout](const boost::system::error_code &ecode) {
if (ecode != boost::asio::error::operation_aborted) {
LogPrint(eLogInfo, "NTCP2: Not connected in ", timeout, " seconds");
conn->Terminate();
}
});
// bind to local address
std::shared_ptr<boost::asio::ip::tcp::endpoint> localAddress;
if (conn->GetRemoteEndpoint().address().is_v6()) {
if (i2p::util::net::IsYggdrasilAddress(conn->GetRemoteEndpoint().address()))
localAddress = m_YggdrasilAddress;
else
localAddress = m_Address6;
conn->GetSocket().open(boost::asio::ip::tcp::v6());
} else {
localAddress = m_Address4;
conn->GetSocket().open(boost::asio::ip::tcp::v4());
}
if (localAddress) {
boost::system::error_code ec;
conn->GetSocket().bind(*localAddress, ec);
if (ec)
LogPrint(eLogError, "NTCP2: Can't bind to ", localAddress->address().to_string(), ": ",
ec.message());
}
conn->GetSocket().async_connect(conn->GetRemoteEndpoint(),
std::bind(&NTCP2Server::HandleConnect, this, std::placeholders::_1,
conn, timer));
} else
conn->Terminate();
});
}
void NTCP2Server::HandleConnect(const boost::system::error_code &ecode, std::shared_ptr<NTCP2Session> conn,
std::shared_ptr<boost::asio::deadline_timer> timer) {
timer->cancel();
if (ecode) {
LogPrint(eLogInfo, "NTCP2: Connect error ", ecode.message());
conn->Terminate();
} else {
LogPrint(eLogDebug, "NTCP2: Connected to ", conn->GetRemoteEndpoint());
conn->ClientLogin();
}
}
void NTCP2Server::HandleAccept(std::shared_ptr<NTCP2Session> conn, const boost::system::error_code &error) {
if (!error) {
boost::system::error_code ec;
auto ep = conn->GetSocket().remote_endpoint(ec);
if (!ec) {
LogPrint(eLogDebug, "NTCP2: Connected from ", ep);
if (conn) {
conn->SetRemoteEndpoint(ep);
conn->ServerLogin();
m_PendingIncomingSessions.push_back(conn);
conn = nullptr;
}
} else
LogPrint(eLogError, "NTCP2: Connected from error ", ec.message());
} else
LogPrint(eLogError, "NTCP2: Accept error ", error.message());
if (error != boost::asio::error::operation_aborted) {
if (!conn) // connection is used, create new one
conn = std::make_shared<NTCP2Session>(*this);
else // reuse failed
conn->Close();
m_NTCP2Acceptor->async_accept(conn->GetSocket(), std::bind(&NTCP2Server::HandleAccept, this,
conn, std::placeholders::_1));
}
}
void NTCP2Server::HandleAcceptV6(std::shared_ptr<NTCP2Session> conn, const boost::system::error_code &error) {
if (!error) {
boost::system::error_code ec;
auto ep = conn->GetSocket().remote_endpoint(ec);
if (!ec) {
LogPrint(eLogDebug, "NTCP2: Connected from ", ep);
if (conn) {
conn->SetRemoteEndpoint(ep);
conn->ServerLogin();
m_PendingIncomingSessions.push_back(conn);
}
} else
LogPrint(eLogError, "NTCP2: Connected from error ", ec.message());
}
if (error != boost::asio::error::operation_aborted) {
conn = std::make_shared<NTCP2Session>(*this);
m_NTCP2V6Acceptor->async_accept(conn->GetSocket(), std::bind(&NTCP2Server::HandleAcceptV6, this,
conn, std::placeholders::_1));
}
}
void NTCP2Server::ScheduleTermination() {
m_TerminationTimer.expires_from_now(boost::posix_time::seconds(NTCP2_TERMINATION_CHECK_TIMEOUT));
m_TerminationTimer.async_wait(std::bind(&NTCP2Server::HandleTerminationTimer,
this, std::placeholders::_1));
}
void NTCP2Server::HandleTerminationTimer(const boost::system::error_code &ecode) {
if (ecode != boost::asio::error::operation_aborted) {
auto ts = i2p::util::GetSecondsSinceEpoch();
// established
for (auto &it: m_NTCP2Sessions)
if (it.second->IsTerminationTimeoutExpired(ts)) {
auto session = it.second;
LogPrint(eLogDebug, "NTCP2: No activity for ", session->GetTerminationTimeout(), " seconds");
session->TerminateByTimeout(); // it doesn't change m_NTCP2Session right a way
} else
it.second->DeleteNextReceiveBuffer(ts);
// pending
for (auto it = m_PendingIncomingSessions.begin(); it != m_PendingIncomingSessions.end();) {
if ((*it)->IsEstablished() || (*it)->IsTerminationTimeoutExpired(ts)) {
(*it)->Terminate();
it = m_PendingIncomingSessions.erase(it); // established of expired
} else if ((*it)->IsTerminated())
it = m_PendingIncomingSessions.erase(it); // already terminated
else
it++;
}
ScheduleTermination();
}
}
void NTCP2Server::ConnectWithProxy(std::shared_ptr<NTCP2Session> conn) {
if (!m_ProxyEndpoint) return;
if (!conn || conn->GetRemoteEndpoint().address().is_unspecified()) {
LogPrint(eLogError, "NTCP2: Can't connect to unspecified address");
return;
}
GetService().post([this, conn]() {
if (this->AddNTCP2Session(conn)) {
auto timer = std::make_shared<boost::asio::deadline_timer>(GetService());
auto timeout = NTCP2_CONNECT_TIMEOUT * 5;
conn->SetTerminationTimeout(timeout * 2);
timer->expires_from_now(boost::posix_time::seconds(timeout));
timer->async_wait([conn, timeout](const boost::system::error_code &ecode) {
if (ecode != boost::asio::error::operation_aborted) {
LogPrint(eLogInfo, "NTCP2: Not connected in ", timeout, " seconds");
conn->Terminate();
}
});
conn->GetSocket().async_connect(*m_ProxyEndpoint, std::bind(&NTCP2Server::HandleProxyConnect, this,
std::placeholders::_1, conn, timer));
}
});
}
void NTCP2Server::UseProxy(ProxyType proxytype, const std::string &addr, uint16_t port,
const std::string &user, const std::string &pass) {
m_ProxyType = proxytype;
m_ProxyAddress = addr;
m_ProxyPort = port;
if (m_ProxyType == eHTTPProxy)
m_ProxyAuthorization = i2p::http::CreateBasicAuthorizationString(user, pass);
}
void NTCP2Server::HandleProxyConnect(const boost::system::error_code &ecode, std::shared_ptr<NTCP2Session> conn,
std::shared_ptr<boost::asio::deadline_timer> timer) {
if (ecode) {
LogPrint(eLogWarning, "NTCP2: Failed to connect to proxy ", ecode.message());
timer->cancel();
conn->Terminate();
return;
}
switch (m_ProxyType) {
case eSocksProxy: {
// TODO: support username/password auth etc
static const uint8_t buff[3] = {0x05, 0x01, 0x00};
boost::asio::async_write(conn->GetSocket(), boost::asio::buffer(buff, 3),
boost::asio::transfer_all(),
[](const boost::system::error_code &ec, std::size_t transferred) {
(void) transferred;
if (ec) {
LogPrint(eLogWarning, "NTCP2: SOCKS5 write error ", ec.message());
}
});
auto readbuff = std::make_shared<std::vector<uint8_t> >(2);
boost::asio::async_read(conn->GetSocket(), boost::asio::buffer(readbuff->data(), 2),
[this, readbuff, timer, conn](const boost::system::error_code &ec,
std::size_t transferred) {
if (ec) {
LogPrint(eLogError, "NTCP2: SOCKS5 read error ", ec.message());
timer->cancel();
conn->Terminate();
return;
} else if (transferred == 2) {
if ((*readbuff)[1] == 0x00) {
AfterSocksHandshake(conn, timer);
return;
} else if ((*readbuff)[1] == 0xff) {
LogPrint(eLogError,
"NTCP2: SOCKS5 proxy rejected authentication");
timer->cancel();
conn->Terminate();
return;
}
LogPrint(eLogError, "NTCP2:", (int) (*readbuff)[1]);
}
LogPrint(eLogError, "NTCP2: SOCKS5 server gave invalid response");
timer->cancel();
conn->Terminate();
});
break;
}
case eHTTPProxy: {
auto &ep = conn->GetRemoteEndpoint();
i2p::http::HTTPReq req;
req.method = "CONNECT";
req.version = "HTTP/1.1";
if (ep.address().is_v6())
req.uri = "[" + ep.address().to_string() + "]:" + std::to_string(ep.port());
else
req.uri = ep.address().to_string() + ":" + std::to_string(ep.port());
if (!m_ProxyAuthorization.empty())
req.AddHeader("Proxy-Authorization", m_ProxyAuthorization);
boost::asio::streambuf writebuff;
std::ostream out(&writebuff);
out << req.to_string();
boost::asio::async_write(conn->GetSocket(), writebuff.data(), boost::asio::transfer_all(),
[](const boost::system::error_code &ec, std::size_t transferred) {
(void) transferred;
if (ec)
LogPrint(eLogError, "NTCP2: HTTP proxy write error ",
ec.message());
});
boost::asio::streambuf *readbuff = new boost::asio::streambuf;
boost::asio::async_read_until(conn->GetSocket(), *readbuff, "\r\n\r\n",
[readbuff, timer, conn](const boost::system::error_code &ec,
std::size_t transferred) {
if (ec) {
LogPrint(eLogError, "NTCP2: HTTP proxy read error ",
ec.message());
timer->cancel();
conn->Terminate();
} else {
readbuff->commit(transferred);
i2p::http::HTTPRes res;
if (res.parse(boost::asio::buffer_cast<const char *>(
readbuff->data()), readbuff->size()) > 0) {
if (res.code == 200) {
timer->cancel();
conn->ClientLogin();
delete readbuff;
return;
} else
LogPrint(eLogError,
"NTCP2: HTTP proxy rejected request ",
res.code);
} else
LogPrint(eLogError,
"NTCP2: HTTP proxy gave malformed response");
timer->cancel();
conn->Terminate();
delete readbuff;
}
});
break;
}
default:
LogPrint(eLogError, "NTCP2: Unknown proxy type, invalid state");
}
}
void NTCP2Server::AfterSocksHandshake(std::shared_ptr<NTCP2Session> conn,
std::shared_ptr<boost::asio::deadline_timer> timer) {
// build request
size_t sz = 6; // header + port
auto buff = std::make_shared<std::vector<int8_t> >(256);
auto readbuff = std::make_shared<std::vector<int8_t> >(256);
(*buff)[0] = 0x05;
(*buff)[1] = 0x01;
(*buff)[2] = 0x00;
auto &ep = conn->GetRemoteEndpoint();
if (ep.address().is_v4()) {
(*buff)[3] = 0x01;
auto addrbytes = ep.address().to_v4().to_bytes();
sz += 4;
memcpy(buff->data() + 4, addrbytes.data(), 4);
} else if (ep.address().is_v6()) {
(*buff)[3] = 0x04;
auto addrbytes = ep.address().to_v6().to_bytes();
sz += 16;
memcpy(buff->data() + 4, addrbytes.data(), 16);
} else {
// We mustn't really fall here because all connections are made to IP addresses
LogPrint(eLogError, "NTCP2: Tried to connect to unexpected address via proxy");
return;
}
htobe16buf(buff->data() + sz - 2, ep.port());
boost::asio::async_write(conn->GetSocket(), boost::asio::buffer(buff->data(), sz),
boost::asio::transfer_all(),
[buff](const boost::system::error_code &ec, std::size_t written) {
if (ec) {
LogPrint(eLogError, "NTCP2: Failed to write handshake to socks proxy ",
ec.message());
return;
}
});
boost::asio::async_read(conn->GetSocket(), boost::asio::buffer(readbuff->data(), 10),
[timer, conn, sz, readbuff](const boost::system::error_code &e,
std::size_t transferred) {
if (e) {
LogPrint(eLogError, "NTCP2: SOCKS proxy read error ", e.message());
} else if (transferred == sz) {
if ((*readbuff)[1] == 0x00) {
timer->cancel();
conn->ClientLogin();
return;
}
}
timer->cancel();
conn->Terminate();
});
}
void NTCP2Server::SetLocalAddress(const boost::asio::ip::address &localAddress) {
auto addr = std::make_shared<boost::asio::ip::tcp::endpoint>(
boost::asio::ip::tcp::endpoint(localAddress, 0));
if (localAddress.is_v6()) {
if (i2p::util::net::IsYggdrasilAddress(localAddress))
m_YggdrasilAddress = addr;
else
m_Address6 = addr;
} else
m_Address4 = addr;
}
}
}