mirror of https://github.com/PurpleI2P/i2pd.git
I2P: End-to-End encrypted and anonymous Internet
https://i2pd.website/
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
330 lines
12 KiB
330 lines
12 KiB
/* |
|
* Copyright (c) 2024, 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 "Log.h" |
|
#include "SSU2.h" |
|
#include "SSU2OutOfSession.h" |
|
|
|
namespace i2p |
|
{ |
|
namespace transport |
|
{ |
|
SSU2PeerTestSession::SSU2PeerTestSession (SSU2Server& server, uint64_t sourceConnID, uint64_t destConnID): |
|
SSU2Session (server, nullptr, nullptr, false), |
|
m_MsgNumReceived (0), m_NumResends (0),m_IsConnectedRecently (false), m_IsStatusChanged (false), |
|
m_PeerTestResendTimer (server.GetService ()) |
|
{ |
|
if (!sourceConnID) sourceConnID = ~destConnID; |
|
if (!destConnID) destConnID = ~sourceConnID; |
|
SetSourceConnID (sourceConnID); |
|
SetDestConnID (destConnID); |
|
SetState (eSSU2SessionStatePeerTest); |
|
SetTerminationTimeout (SSU2_PEER_TEST_EXPIRATION_TIMEOUT); |
|
} |
|
|
|
bool SSU2PeerTestSession::ProcessPeerTest (uint8_t * buf, size_t len) |
|
{ |
|
// we are Alice or Charlie, msgs 5,6,7 |
|
Header header; |
|
memcpy (header.buf, buf, 16); |
|
header.ll[0] ^= CreateHeaderMask (i2p::context.GetSSU2IntroKey (), buf + (len - 24)); |
|
header.ll[1] ^= CreateHeaderMask (i2p::context.GetSSU2IntroKey (), buf + (len - 12)); |
|
if (header.h.type != eSSU2PeerTest) |
|
{ |
|
LogPrint (eLogWarning, "SSU2: Unexpected message type ", (int)header.h.type, " instead ", (int)eSSU2PeerTest); |
|
return false; |
|
} |
|
if (len < 48) |
|
{ |
|
LogPrint (eLogWarning, "SSU2: PeerTest message too short ", len); |
|
return false; |
|
} |
|
uint8_t nonce[12] = {0}; |
|
uint64_t headerX[2]; // sourceConnID, token |
|
i2p::crypto::ChaCha20 (buf + 16, 16, i2p::context.GetSSU2IntroKey (), nonce, (uint8_t *)headerX); |
|
SetDestConnID (headerX[0]); |
|
// decrypt and handle payload |
|
uint8_t * payload = buf + 32; |
|
CreateNonce (be32toh (header.h.packetNum), nonce); |
|
uint8_t h[32]; |
|
memcpy (h, header.buf, 16); |
|
memcpy (h + 16, &headerX, 16); |
|
if (!i2p::crypto::AEADChaCha20Poly1305 (payload, len - 48, h, 32, |
|
i2p::context.GetSSU2IntroKey (), nonce, payload, len - 48, false)) |
|
{ |
|
LogPrint (eLogWarning, "SSU2: PeerTest AEAD verification failed "); |
|
return false; |
|
} |
|
HandlePayload (payload, len - 48); |
|
SetIsDataReceived (false); |
|
return true; |
|
} |
|
|
|
void SSU2PeerTestSession::HandlePeerTest (const uint8_t * buf, size_t len) |
|
{ |
|
// msgs 5-7 |
|
if (len < 8) return; |
|
uint8_t msg = buf[0]; |
|
if (msg <= m_MsgNumReceived) |
|
{ |
|
LogPrint (eLogDebug, "SSU2: PeerTest msg num ", msg, " received after ", m_MsgNumReceived, ". Ignored"); |
|
return; |
|
} |
|
size_t offset = 3; // points to signed data after msg + code + flag |
|
uint32_t nonce = bufbe32toh (buf + offset + 1); // 1 - ver |
|
switch (msg) // msg |
|
{ |
|
case 5: // Alice from Charlie 1 |
|
{ |
|
if (htobe64 (((uint64_t)nonce << 32) | nonce) == GetSourceConnID ()) |
|
{ |
|
m_IsConnectedRecently = GetServer ().IsConnectedRecently (GetRemoteEndpoint ()); |
|
if (GetAddress ()) |
|
{ |
|
if (!m_IsConnectedRecently) |
|
SetRouterStatus (eRouterStatusOK); |
|
else if (m_IsStatusChanged && GetRouterStatus () == eRouterStatusFirewalled) |
|
SetRouterStatus (eRouterStatusUnknown); |
|
SendPeerTest (6, buf + offset, len - offset); |
|
} |
|
} |
|
else |
|
LogPrint (eLogWarning, "SSU2: Peer test 5 nonce mismatch ", nonce, " connID=", GetSourceConnID ()); |
|
break; |
|
} |
|
case 6: // Charlie from Alice |
|
{ |
|
m_PeerTestResendTimer.cancel (); // no more msg 5 resends |
|
if (GetAddress ()) |
|
SendPeerTest (7, buf + offset, len - offset); |
|
else |
|
LogPrint (eLogWarning, "SSU2: Unknown address for peer test 6"); |
|
GetServer ().AddConnectedRecently (GetRemoteEndpoint (), i2p::util::GetSecondsSinceEpoch ()); |
|
GetServer ().RequestRemoveSession (GetConnID ()); |
|
break; |
|
} |
|
case 7: // Alice from Charlie 2 |
|
{ |
|
m_PeerTestResendTimer.cancel (); // no more msg 6 resends |
|
auto addr = GetAddress (); |
|
if (addr && addr->IsV6 ()) |
|
i2p::context.SetStatusV6 (eRouterStatusOK); // set status OK for ipv6 even if from SSU2 |
|
GetServer ().AddConnectedRecently (GetRemoteEndpoint (), i2p::util::GetSecondsSinceEpoch ()); |
|
GetServer ().RequestRemoveSession (GetConnID ()); |
|
break; |
|
} |
|
default: |
|
LogPrint (eLogWarning, "SSU2: PeerTest unexpected msg num ", msg); |
|
return; |
|
} |
|
m_MsgNumReceived = msg; |
|
} |
|
|
|
void SSU2PeerTestSession::SendPeerTest (uint8_t msg) |
|
{ |
|
auto addr = GetAddress (); |
|
if (!addr) return; |
|
Header header; |
|
uint8_t h[32], payload[SSU2_MAX_PACKET_SIZE]; |
|
// fill packet |
|
header.h.connID = GetDestConnID (); // dest id |
|
RAND_bytes (header.buf + 8, 4); // random packet num |
|
header.h.type = eSSU2PeerTest; |
|
header.h.flags[0] = 2; // ver |
|
header.h.flags[1] = (uint8_t)i2p::context.GetNetID (); // netID |
|
header.h.flags[2] = 0; // flag |
|
memcpy (h, header.buf, 16); |
|
htobuf64 (h + 16, GetSourceConnID ()); // source id |
|
// payload |
|
payload[0] = eSSU2BlkDateTime; |
|
htobe16buf (payload + 1, 4); |
|
htobe32buf (payload + 3, (i2p::util::GetMillisecondsSinceEpoch () + 500)/1000); |
|
size_t payloadSize = 7; |
|
if (msg == 6 || msg == 7) |
|
payloadSize += CreateAddressBlock (payload + payloadSize, GetMaxPayloadSize () - payloadSize, GetRemoteEndpoint ()); |
|
payloadSize += CreatePeerTestBlock (payload + payloadSize, GetMaxPayloadSize () - payloadSize, |
|
msg, eSSU2PeerTestCodeAccept, nullptr, m_SignedData.data (), m_SignedData.size ()); |
|
payloadSize += CreatePaddingBlock (payload + payloadSize, GetMaxPayloadSize () - payloadSize); |
|
// encrypt |
|
uint8_t n[12]; |
|
CreateNonce (be32toh (header.h.packetNum), n); |
|
i2p::crypto::AEADChaCha20Poly1305 (payload, payloadSize, h, 32, addr->i, n, payload, payloadSize + 16, true); |
|
payloadSize += 16; |
|
header.ll[0] ^= CreateHeaderMask (addr->i, payload + (payloadSize - 24)); |
|
header.ll[1] ^= CreateHeaderMask (addr->i, payload + (payloadSize - 12)); |
|
memset (n, 0, 12); |
|
i2p::crypto::ChaCha20 (h + 16, 16, addr->i, n, h + 16); |
|
// send |
|
GetServer ().Send (header.buf, 16, h + 16, 16, payload, payloadSize, GetRemoteEndpoint ()); |
|
} |
|
|
|
void SSU2PeerTestSession::SendPeerTest (uint8_t msg, const uint8_t * signedData, size_t signedDataLen) |
|
{ |
|
#if __cplusplus >= 202002L // C++20 |
|
m_SignedData.assign (signedData, signedData + signedDataLen); |
|
#else |
|
m_SignedData.resize (signedDataLen); |
|
memcpy (m_SignedData.data (), signedData, signedDataLen); |
|
#endif |
|
SendPeerTest (msg); |
|
// schedule resend for msgs 5 or 6 |
|
if (msg == 5 || msg == 6) |
|
ScheduleResend (); |
|
} |
|
|
|
void SSU2PeerTestSession::SendPeerTest (uint8_t msg, const uint8_t * signedData, size_t signedDataLen, |
|
std::shared_ptr<const i2p::data::RouterInfo::Address> addr) |
|
{ |
|
if (!addr) return; |
|
SetAddress (addr); |
|
SendPeerTest (msg, signedData, signedDataLen); |
|
} |
|
|
|
void SSU2PeerTestSession::Connect () |
|
{ |
|
LogPrint (eLogError, "SSU2: Can't connect peer test session"); |
|
} |
|
|
|
bool SSU2PeerTestSession::ProcessFirstIncomingMessage (uint64_t connID, uint8_t * buf, size_t len) |
|
{ |
|
LogPrint (eLogError, "SSU2: Can't handle incoming message in peer test session"); |
|
return false; |
|
} |
|
|
|
void SSU2PeerTestSession::ScheduleResend () |
|
{ |
|
if (m_NumResends < SSU2_PEER_TEST_MAX_NUM_RESENDS) |
|
{ |
|
m_PeerTestResendTimer.expires_from_now (boost::posix_time::milliseconds( |
|
SSU2_PEER_TEST_RESEND_INTERVAL + GetServer ().GetRng ()() % SSU2_PEER_TEST_RESEND_INTERVAL_VARIANCE)); |
|
std::weak_ptr<SSU2PeerTestSession> s(std::static_pointer_cast<SSU2PeerTestSession>(shared_from_this ())); |
|
m_PeerTestResendTimer.async_wait ([s](const boost::system::error_code& ecode) |
|
{ |
|
if (ecode != boost::asio::error::operation_aborted) |
|
{ |
|
auto s1 = s.lock (); |
|
if (s1) |
|
{ |
|
int msg = 0; |
|
if (s1->m_MsgNumReceived < 6) |
|
msg = (s1->m_MsgNumReceived == 5) ? 6 : 5; |
|
if (msg) // 5 or 6 |
|
{ |
|
s1->SendPeerTest (msg); |
|
s1->ScheduleResend (); |
|
} |
|
} |
|
} |
|
}); |
|
m_NumResends++; |
|
} |
|
} |
|
|
|
SSU2HolePunchSession::SSU2HolePunchSession (SSU2Server& server, uint32_t nonce, |
|
const boost::asio::ip::udp::endpoint& remoteEndpoint, |
|
std::shared_ptr<const i2p::data::RouterInfo::Address> addr): |
|
SSU2Session (server), // we create full incoming session |
|
m_Nonce (nonce), m_NumResends (0), m_HolePunchResendTimer (server.GetService ()) |
|
{ |
|
// we are Charlie |
|
uint64_t destConnID = htobe64 (((uint64_t)nonce << 32) | nonce); // dest id |
|
uint32_t sourceConnID = ~destConnID; |
|
SetSourceConnID (sourceConnID); |
|
SetDestConnID (destConnID); |
|
SetState (eSSU2SessionStateHolePunch); |
|
SetRemoteEndpoint (remoteEndpoint); |
|
SetAddress (addr); |
|
SetTerminationTimeout (SSU2_RELAY_NONCE_EXPIRATION_TIMEOUT); |
|
} |
|
|
|
void SSU2HolePunchSession::SendHolePunch () |
|
{ |
|
auto addr = GetAddress (); |
|
if (!addr) return; |
|
auto& ep = GetRemoteEndpoint (); |
|
LogPrint (eLogDebug, "SSU2: Sending HolePunch to ", ep); |
|
Header header; |
|
uint8_t h[32], payload[SSU2_MAX_PACKET_SIZE]; |
|
// fill packet |
|
header.h.connID = GetDestConnID (); // dest id |
|
RAND_bytes (header.buf + 8, 4); // random packet num |
|
header.h.type = eSSU2HolePunch; |
|
header.h.flags[0] = 2; // ver |
|
header.h.flags[1] = (uint8_t)i2p::context.GetNetID (); // netID |
|
header.h.flags[2] = 0; // flag |
|
memcpy (h, header.buf, 16); |
|
htobuf64 (h + 16, GetSourceConnID ()); // source id |
|
RAND_bytes (h + 24, 8); // header token, to be ignored by Alice |
|
// payload |
|
payload[0] = eSSU2BlkDateTime; |
|
htobe16buf (payload + 1, 4); |
|
htobe32buf (payload + 3, (i2p::util::GetMillisecondsSinceEpoch () + 500)/1000); |
|
size_t payloadSize = 7; |
|
payloadSize += CreateAddressBlock (payload + payloadSize, GetMaxPayloadSize () - payloadSize, ep); |
|
// relay response block |
|
if (payloadSize + m_RelayResponseBlock.size () < GetMaxPayloadSize ()) |
|
{ |
|
memcpy (payload + payloadSize, m_RelayResponseBlock.data (), m_RelayResponseBlock.size ()); |
|
payloadSize += m_RelayResponseBlock.size (); |
|
} |
|
payloadSize += CreatePaddingBlock (payload + payloadSize, GetMaxPayloadSize () - payloadSize); |
|
// encrypt |
|
uint8_t n[12]; |
|
CreateNonce (be32toh (header.h.packetNum), n); |
|
i2p::crypto::AEADChaCha20Poly1305 (payload, payloadSize, h, 32, addr->i, n, payload, payloadSize + 16, true); |
|
payloadSize += 16; |
|
header.ll[0] ^= CreateHeaderMask (addr->i, payload + (payloadSize - 24)); |
|
header.ll[1] ^= CreateHeaderMask (addr->i, payload + (payloadSize - 12)); |
|
memset (n, 0, 12); |
|
i2p::crypto::ChaCha20 (h + 16, 16, addr->i, n, h + 16); |
|
// send |
|
GetServer ().Send (header.buf, 16, h + 16, 16, payload, payloadSize, ep); |
|
} |
|
|
|
void SSU2HolePunchSession::SendHolePunch (const uint8_t * relayResponseBlock, size_t relayResponseBlockLen) |
|
{ |
|
#if __cplusplus >= 202002L // C++20 |
|
m_RelayResponseBlock.assign (relayResponseBlock, relayResponseBlock + relayResponseBlockLen); |
|
#else |
|
m_RelayResponseBlock.resize (relayResponseBlockLen); |
|
memcpy (m_RelayResponseBlock.data (), relayResponseBlock, relayResponseBlockLen); |
|
#endif |
|
SendHolePunch (); |
|
ScheduleResend (); |
|
} |
|
|
|
void SSU2HolePunchSession::ScheduleResend () |
|
{ |
|
if (m_NumResends < SSU2_HOLE_PUNCH_MAX_NUM_RESENDS) |
|
{ |
|
m_HolePunchResendTimer.expires_from_now (boost::posix_time::milliseconds( |
|
SSU2_HOLE_PUNCH_RESEND_INTERVAL + GetServer ().GetRng ()() % SSU2_HOLE_PUNCH_RESEND_INTERVAL_VARIANCE)); |
|
std::weak_ptr<SSU2HolePunchSession> s(std::static_pointer_cast<SSU2HolePunchSession>(shared_from_this ())); |
|
m_HolePunchResendTimer.async_wait ([s](const boost::system::error_code& ecode) |
|
{ |
|
if (ecode != boost::asio::error::operation_aborted) |
|
{ |
|
auto s1 = s.lock (); |
|
if (s1 && s1->GetState () == eSSU2SessionStateHolePunch) |
|
{ |
|
s1->SendHolePunch (); |
|
s1->ScheduleResend (); |
|
} |
|
} |
|
}); |
|
m_NumResends++; |
|
} |
|
} |
|
|
|
bool SSU2HolePunchSession::ProcessFirstIncomingMessage (uint64_t connID, uint8_t * buf, size_t len) |
|
{ |
|
m_HolePunchResendTimer.cancel (); |
|
return SSU2Session::ProcessFirstIncomingMessage (connID, buf, len); |
|
} |
|
} |
|
}
|
|
|