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/*
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* Copyright (c) 2022-2024, The PurpleI2P Project
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*
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* This file is part of Purple i2pd project and licensed under BSD3
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*
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* See full license text in LICENSE file at top of project tree
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*/
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#include <string.h>
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#include <openssl/rand.h>
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#include "Log.h"
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#include "Transports.h"
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#include "Gzip.h"
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#include "NetDb.hpp"
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#include "SSU2.h"
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#include "SSU2Session.h"
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namespace i2p
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{
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namespace transport
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{
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void SSU2IncompleteMessage::AttachNextFragment (const uint8_t * fragment, size_t fragmentSize)
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{
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if (msg->len + fragmentSize > msg->maxLen)
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{
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LogPrint (eLogInfo, "SSU2: I2NP message size ", msg->maxLen, " is not enough");
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auto newMsg = NewI2NPMessage (msg->len + fragmentSize);
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*newMsg = *msg;
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msg = newMsg;
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}
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if (msg->Concat (fragment, fragmentSize) < fragmentSize)
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LogPrint (eLogError, "SSU2: I2NP buffer overflow ", msg->maxLen);
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nextFragmentNum++;
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}
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bool SSU2IncompleteMessage::ConcatOutOfSequenceFragments ()
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{
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bool isLast = false;
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while (outOfSequenceFragments)
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{
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if (outOfSequenceFragments->fragmentNum == nextFragmentNum)
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{
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AttachNextFragment (outOfSequenceFragments->buf, outOfSequenceFragments->len);
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isLast = outOfSequenceFragments->isLast;
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if (isLast)
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outOfSequenceFragments = nullptr;
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else
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outOfSequenceFragments = outOfSequenceFragments->next;
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}
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else
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break;
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}
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return isLast;
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}
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void SSU2IncompleteMessage::AddOutOfSequenceFragment (std::shared_ptr<SSU2IncompleteMessage::Fragment> fragment)
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{
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if (!fragment || !fragment->fragmentNum) return; // fragment 0 not allowed
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if (fragment->fragmentNum < nextFragmentNum) return; // already processed
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if (!outOfSequenceFragments)
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outOfSequenceFragments = fragment;
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else
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{
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auto frag = outOfSequenceFragments;
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std::shared_ptr<Fragment> prev;
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do
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{
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if (fragment->fragmentNum < frag->fragmentNum) break; // found
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if (fragment->fragmentNum == frag->fragmentNum) return; // duplicate
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prev = frag; frag = frag->next;
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}
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while (frag);
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fragment->next = frag;
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if (prev)
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prev->next = fragment;
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else
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outOfSequenceFragments = fragment;
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}
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lastFragmentInsertTime = i2p::util::GetSecondsSinceEpoch ();
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}
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SSU2Session::SSU2Session (SSU2Server& server, std::shared_ptr<const i2p::data::RouterInfo> in_RemoteRouter,
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std::shared_ptr<const i2p::data::RouterInfo::Address> addr, bool noise):
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TransportSession (in_RemoteRouter, SSU2_CONNECT_TIMEOUT),
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m_Server (server), m_Address (addr), m_RemoteTransports (0), m_RemotePeerTestTransports (0),
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m_DestConnID (0), m_SourceConnID (0), m_State (eSSU2SessionStateUnknown),
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m_SendPacketNum (0), m_ReceivePacketNum (0), m_LastDatetimeSentPacketNum (0),
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m_IsDataReceived (false), m_RTT (SSU2_UNKNOWN_RTT),
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m_MsgLocalExpirationTimeout (I2NP_MESSAGE_LOCAL_EXPIRATION_TIMEOUT_MAX),
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m_MsgLocalSemiExpirationTimeout (I2NP_MESSAGE_LOCAL_EXPIRATION_TIMEOUT_MAX / 2),
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m_WindowSize (SSU2_MIN_WINDOW_SIZE),
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m_RTO (SSU2_INITIAL_RTO), m_RelayTag (0),m_ConnectTimer (server.GetService ()),
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m_TerminationReason (eSSU2TerminationReasonNormalClose),
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m_MaxPayloadSize (SSU2_MIN_PACKET_SIZE - IPV6_HEADER_SIZE - UDP_HEADER_SIZE - 32), // min size
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m_LastResendTime (0), m_LastResendAttemptTime (0)
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{
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if (noise)
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m_NoiseState.reset (new i2p::crypto::NoiseSymmetricState);
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if (in_RemoteRouter && m_Address)
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{
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// outgoing
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if (noise)
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InitNoiseXKState1 (*m_NoiseState, m_Address->s);
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m_RemoteEndpoint = boost::asio::ip::udp::endpoint (m_Address->host, m_Address->port);
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m_RemoteTransports = in_RemoteRouter->GetCompatibleTransports (false);
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if (in_RemoteRouter->IsSSU2PeerTesting (true)) m_RemotePeerTestTransports |= i2p::data::RouterInfo::eSSU2V4;
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if (in_RemoteRouter->IsSSU2PeerTesting (false)) m_RemotePeerTestTransports |= i2p::data::RouterInfo::eSSU2V6;
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RAND_bytes ((uint8_t *)&m_DestConnID, 8);
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RAND_bytes ((uint8_t *)&m_SourceConnID, 8);
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}
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else
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{
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// incoming
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if (noise)
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InitNoiseXKState1 (*m_NoiseState, i2p::context.GetSSU2StaticPublicKey ());
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}
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}
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SSU2Session::~SSU2Session ()
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{
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}
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void SSU2Session::Connect ()
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{
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if (m_State == eSSU2SessionStateUnknown || m_State == eSSU2SessionStateTokenReceived)
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{
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LogPrint(eLogDebug, "SSU2: Connecting to ", GetRemoteEndpoint (),
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" (", i2p::data::GetIdentHashAbbreviation (GetRemoteIdentity ()->GetIdentHash ()), ")");
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ScheduleConnectTimer ();
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auto token = m_Server.FindOutgoingToken (m_RemoteEndpoint);
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if (token)
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SendSessionRequest (token);
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else
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{
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m_State = eSSU2SessionStateUnknown;
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SendTokenRequest ();
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}
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}
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}
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void SSU2Session::ScheduleConnectTimer ()
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{
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m_ConnectTimer.cancel ();
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m_ConnectTimer.expires_from_now (boost::posix_time::seconds(SSU2_CONNECT_TIMEOUT));
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m_ConnectTimer.async_wait (std::bind (&SSU2Session::HandleConnectTimer,
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shared_from_this (), std::placeholders::_1));
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}
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void SSU2Session::HandleConnectTimer (const boost::system::error_code& ecode)
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{
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if (!ecode && m_State != eSSU2SessionStateTerminated)
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{
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// timeout expired
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if (m_State == eSSU2SessionStateIntroduced) // WaitForIntroducer
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LogPrint (eLogWarning, "SSU2: Session was not introduced after ", SSU2_CONNECT_TIMEOUT, " seconds");
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else
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LogPrint (eLogWarning, "SSU2: Session with ", m_RemoteEndpoint, " was not established after ", SSU2_CONNECT_TIMEOUT, " seconds");
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Terminate ();
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}
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}
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bool SSU2Session::Introduce (std::shared_ptr<SSU2Session> session, uint32_t relayTag)
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{
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// we are Alice
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if (!session || !relayTag) return false;
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// find local address to introduce
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auto localAddress = session->FindLocalAddress ();
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if (!localAddress || localAddress->host.is_unspecified () || !localAddress->port)
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{
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// can't introduce invalid endpoint
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LogPrint (eLogWarning, "SSU2: Can't find local address to introduce");
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return false;
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}
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// create nonce
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uint32_t nonce;
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RAND_bytes ((uint8_t *)&nonce, 4);
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auto ts = i2p::util::GetMillisecondsSinceEpoch ();
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// payload
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auto packet = m_Server.GetSentPacketsPool ().AcquireShared ();
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uint8_t * payload = packet->payload;
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payload[0] = eSSU2BlkRelayRequest;
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payload[3] = 0; // flag
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htobe32buf (payload + 4, nonce);
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htobe32buf (payload + 8, relayTag);
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htobe32buf (payload + 12, ts/1000);
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payload[16] = 2; // ver
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size_t asz = CreateEndpoint (payload + 18, m_MaxPayloadSize - 18, boost::asio::ip::udp::endpoint (localAddress->host, localAddress->port));
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if (!asz) return false;
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payload[17] = asz;
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packet->payloadSize = asz + 18;
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SignedData s;
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s.Insert ((const uint8_t *)"RelayRequestData", 16); // prologue
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s.Insert (GetRemoteIdentity ()->GetIdentHash (), 32); // bhash
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s.Insert (session->GetRemoteIdentity ()->GetIdentHash (), 32); // chash
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s.Insert (payload + 4, 14 + asz); // nonce, relay tag, timestamp, ver, asz and Alice's endpoint
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s.Sign (i2p::context.GetPrivateKeys (), payload + packet->payloadSize);
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packet->payloadSize += i2p::context.GetIdentity ()->GetSignatureLen ();
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htobe16buf (payload + 1, packet->payloadSize - 3); // size
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packet->payloadSize += CreatePaddingBlock (payload + packet->payloadSize, m_MaxPayloadSize - packet->payloadSize);
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// send
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m_RelaySessions.emplace (nonce, std::make_pair (session, ts/1000));
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session->m_SourceConnID = htobe64 (((uint64_t)nonce << 32) | nonce);
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session->m_DestConnID = ~session->m_SourceConnID;
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m_Server.AddSession (session);
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int32_t packetNum = SendData (packet->payload, packet->payloadSize);
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packet->sendTime = ts;
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m_SentPackets.emplace (packetNum, packet);
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return true;
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}
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void SSU2Session::WaitForIntroduction ()
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{
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m_State = eSSU2SessionStateIntroduced;
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ScheduleConnectTimer ();
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}
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void SSU2Session::ConnectAfterIntroduction ()
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{
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if (m_State == eSSU2SessionStateIntroduced)
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{
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// we are Alice
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// keep ConnIDs used for introduction, because Charlie waits for SessionRequest from us
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m_State = eSSU2SessionStateTokenReceived;
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// move session to pending outgoing
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if (m_Server.AddPendingOutgoingSession (shared_from_this ()))
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{
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m_Server.RemoveSession (GetConnID ());
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// connect
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LogPrint (eLogDebug, "SSU2: Connecting after introduction to ", GetIdentHashBase64());
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Connect ();
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}
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else
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{
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LogPrint (eLogError, "SSU2: Session ", GetConnID (), " is already pending");
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m_Server.RequestRemoveSession (GetConnID ());
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}
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}
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}
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void SSU2Session::SendPeerTest ()
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{
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// we are Alice
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uint32_t nonce;
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RAND_bytes ((uint8_t *)&nonce, 4);
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auto ts = i2p::util::GetMillisecondsSinceEpoch ();
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// session for message 5
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auto session = std::make_shared<SSU2PeerTestSession> (m_Server,
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htobe64 (((uint64_t)nonce << 32) | nonce), 0);
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m_Server.AddRequestedPeerTest (nonce, session, ts/1000);
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m_Server.AddSession (session);
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// peer test block
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auto packet = m_Server.GetSentPacketsPool ().AcquireShared ();
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packet->payloadSize = CreatePeerTestBlock (packet->payload, m_MaxPayloadSize, nonce);
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if (packet->payloadSize > 0)
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{
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packet->payloadSize += CreatePaddingBlock (packet->payload + packet->payloadSize, m_MaxPayloadSize - packet->payloadSize);
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uint32_t packetNum = SendData (packet->payload, packet->payloadSize, SSU2_FLAG_IMMEDIATE_ACK_REQUESTED);
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packet->sendTime = ts;
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m_SentPackets.emplace (packetNum, packet);
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LogPrint (eLogDebug, "SSU2: PeerTest msg=1 sent to ", i2p::data::GetIdentHashAbbreviation (GetRemoteIdentity ()->GetIdentHash ()));
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}
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}
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void SSU2Session::SendKeepAlive ()
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{
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if (IsEstablished ())
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{
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uint8_t payload[20];
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size_t payloadSize = CreatePaddingBlock (payload, 20, 8);
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SendData (payload, payloadSize, SSU2_FLAG_IMMEDIATE_ACK_REQUESTED);
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}
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}
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void SSU2Session::Terminate ()
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{
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if (m_State != eSSU2SessionStateTerminated)
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{
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m_State = eSSU2SessionStateTerminated;
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m_ConnectTimer.cancel ();
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m_OnEstablished = nullptr;
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if (m_RelayTag)
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m_Server.RemoveRelay (m_RelayTag);
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m_Server.AddConnectedRecently (m_RemoteEndpoint, GetLastActivityTimestamp ());
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m_SentHandshakePacket.reset (nullptr);
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m_SessionConfirmedFragment.reset (nullptr);
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m_PathChallenge.reset (nullptr);
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for (auto& it: m_SendQueue)
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it->Drop ();
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m_SendQueue.clear ();
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SetSendQueueSize (0);
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m_SentPackets.clear ();
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m_IncompleteMessages.clear ();
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m_RelaySessions.clear ();
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m_ReceivedI2NPMsgIDs.clear ();
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m_Server.RemoveSession (m_SourceConnID);
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transports.PeerDisconnected (shared_from_this ());
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auto remoteIdentity = GetRemoteIdentity ();
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if (remoteIdentity)
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LogPrint (eLogDebug, "SSU2: Session with ", GetRemoteEndpoint (),
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" (", i2p::data::GetIdentHashAbbreviation (remoteIdentity->GetIdentHash ()), ") terminated");
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else
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LogPrint (eLogDebug, "SSU2: Session with ", GetRemoteEndpoint (), " terminated");
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}
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}
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void SSU2Session::RequestTermination (SSU2TerminationReason reason)
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{
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if (m_State == eSSU2SessionStateEstablished || m_State == eSSU2SessionStateClosing)
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{
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m_TerminationReason = reason;
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SendTermination ();
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m_State = eSSU2SessionStateClosing;
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}
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else
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Done ();
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}
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void SSU2Session::Established ()
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{
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m_State = eSSU2SessionStateEstablished;
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m_EphemeralKeys = nullptr;
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m_NoiseState.reset (nullptr);
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m_SessionConfirmedFragment.reset (nullptr);
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m_SentHandshakePacket.reset (nullptr);
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m_ConnectTimer.cancel ();
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SetTerminationTimeout (SSU2_TERMINATION_TIMEOUT);
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SendQueue ();
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transports.PeerConnected (shared_from_this ());
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if (m_OnEstablished)
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{
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m_OnEstablished ();
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m_OnEstablished = nullptr;
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}
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LogPrint(eLogDebug, "SSU2: Session with ", GetRemoteEndpoint (),
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" (", i2p::data::GetIdentHashAbbreviation (GetRemoteIdentity ()->GetIdentHash ()), ") established");
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}
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void SSU2Session::Done ()
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{
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m_Server.GetService ().post (std::bind (&SSU2Session::Terminate, shared_from_this ()));
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}
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|
|
|
|
|
void SSU2Session::SendLocalRouterInfo (bool update)
|
|
|
|
{
|
|
|
|
if (update || !IsOutgoing ())
|
|
|
|
{
|
|
|
|
auto s = shared_from_this ();
|
|
|
|
m_Server.GetService ().post ([s]()
|
|
|
|
{
|
|
|
|
if (!s->IsEstablished ()) return;
|
|
|
|
uint8_t payload[SSU2_MAX_PACKET_SIZE];
|
|
|
|
size_t payloadSize = s->CreateRouterInfoBlock (payload, s->m_MaxPayloadSize - 32, i2p::context.CopyRouterInfoBuffer ());
|
|
|
|
if (payloadSize)
|
|
|
|
{
|
|
|
|
if (payloadSize < s->m_MaxPayloadSize)
|
|
|
|
payloadSize += s->CreatePaddingBlock (payload + payloadSize, s->m_MaxPayloadSize - payloadSize);
|
|
|
|
s->SendData (payload, payloadSize);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
s->SendFragmentedMessage (CreateDatabaseStoreMsg ());
|
|
|
|
});
|
|
|
|
}
|
|
|
|
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::SendI2NPMessages (const std::vector<std::shared_ptr<I2NPMessage> >& msgs)
|
|
|
|
{
|
|
|
|
m_Server.GetService ().post (std::bind (&SSU2Session::PostI2NPMessages, shared_from_this (), msgs));
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::PostI2NPMessages (std::vector<std::shared_ptr<I2NPMessage> > msgs)
|
|
|
|
{
|
|
|
|
if (m_State == eSSU2SessionStateTerminated) return;
|
|
|
|
uint64_t mts = i2p::util::GetMonotonicMicroseconds ();
|
|
|
|
bool isSemiFull = false;
|
|
|
|
if (m_SendQueue.size ())
|
|
|
|
{
|
|
|
|
int64_t queueLag = (int64_t)mts - (int64_t)m_SendQueue.front ()->GetEnqueueTime ();
|
|
|
|
isSemiFull = queueLag > m_MsgLocalSemiExpirationTimeout;
|
|
|
|
if (isSemiFull)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Outgoing messages queue to ",
|
|
|
|
i2p::data::GetIdentHashAbbreviation (GetRemoteIdentity ()->GetIdentHash ()),
|
|
|
|
" is semi-full (size = ", m_SendQueue.size (), ", lag = ", queueLag / 1000, ", rtt = ", (int)m_RTT, ")");
|
|
|
|
}
|
|
|
|
}
|
|
|
|
for (auto it: msgs)
|
|
|
|
{
|
|
|
|
if (isSemiFull && it->onDrop)
|
|
|
|
it->Drop (); // drop earlier because we can handle it
|
|
|
|
else
|
|
|
|
{
|
|
|
|
it->SetEnqueueTime (mts);
|
|
|
|
m_SendQueue.push_back (std::move (it));
|
|
|
|
}
|
|
|
|
}
|
|
|
|
if (IsEstablished ())
|
|
|
|
{
|
|
|
|
SendQueue ();
|
|
|
|
if (m_SendQueue.size () > 0) // windows is full
|
|
|
|
Resend (i2p::util::GetMillisecondsSinceEpoch ());
|
|
|
|
}
|
|
|
|
SetSendQueueSize (m_SendQueue.size ());
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::MoveSendQueue (std::shared_ptr<SSU2Session> other)
|
|
|
|
{
|
|
|
|
if (!other || m_SendQueue.empty ()) return;
|
|
|
|
std::vector<std::shared_ptr<I2NPMessage> > msgs;
|
|
|
|
auto ts = i2p::util::GetMillisecondsSinceEpoch ();
|
|
|
|
for (auto it: m_SendQueue)
|
|
|
|
if (!it->IsExpired (ts))
|
|
|
|
msgs.push_back (it);
|
|
|
|
else
|
|
|
|
it->Drop ();
|
|
|
|
m_SendQueue.clear ();
|
|
|
|
if (!msgs.empty ())
|
|
|
|
other->PostI2NPMessages (msgs);
|
|
|
|
}
|
|
|
|
|
|
|
|
bool SSU2Session::SendQueue ()
|
|
|
|
{
|
|
|
|
if (!m_SendQueue.empty () && m_SentPackets.size () <= m_WindowSize && IsEstablished ())
|
|
|
|
{
|
|
|
|
auto ts = i2p::util::GetMillisecondsSinceEpoch ();
|
|
|
|
uint64_t mts = i2p::util::GetMonotonicMicroseconds ();
|
|
|
|
auto packet = m_Server.GetSentPacketsPool ().AcquireShared ();
|
|
|
|
size_t ackBlockSize = CreateAckBlock (packet->payload, m_MaxPayloadSize);
|
|
|
|
bool ackBlockSent = false;
|
|
|
|
packet->payloadSize += ackBlockSize;
|
|
|
|
while (!m_SendQueue.empty () && m_SentPackets.size () <= m_WindowSize)
|
|
|
|
{
|
|
|
|
auto msg = m_SendQueue.front ();
|
|
|
|
if (!msg || msg->IsExpired (ts) || msg->GetEnqueueTime() + m_MsgLocalExpirationTimeout < mts)
|
|
|
|
{
|
|
|
|
// drop null or expired message
|
|
|
|
if (msg) msg->Drop ();
|
|
|
|
m_SendQueue.pop_front ();
|
|
|
|
continue;
|
|
|
|
}
|
|
|
|
size_t len = msg->GetNTCP2Length () + 3;
|
|
|
|
if (len > m_MaxPayloadSize) // message too long
|
|
|
|
{
|
|
|
|
m_SendQueue.pop_front ();
|
|
|
|
if (SendFragmentedMessage (msg))
|
|
|
|
ackBlockSent = true;
|
|
|
|
}
|
|
|
|
else if (packet->payloadSize + len <= m_MaxPayloadSize)
|
|
|
|
{
|
|
|
|
m_SendQueue.pop_front ();
|
|
|
|
packet->payloadSize += CreateI2NPBlock (packet->payload + packet->payloadSize, m_MaxPayloadSize - packet->payloadSize, std::move (msg));
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
// create new packet and copy ack block
|
|
|
|
auto newPacket = m_Server.GetSentPacketsPool ().AcquireShared ();
|
|
|
|
memcpy (newPacket->payload, packet->payload, ackBlockSize);
|
|
|
|
newPacket->payloadSize = ackBlockSize;
|
|
|
|
// complete current packet
|
|
|
|
if (packet->payloadSize > ackBlockSize) // more than just ack block
|
|
|
|
{
|
|
|
|
ackBlockSent = true;
|
|
|
|
// try to add padding
|
|
|
|
if (packet->payloadSize + 16 < m_MaxPayloadSize)
|
|
|
|
packet->payloadSize += CreatePaddingBlock (packet->payload + packet->payloadSize, m_MaxPayloadSize - packet->payloadSize);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
// reduce ack block
|
|
|
|
if (len + 8 < m_MaxPayloadSize)
|
|
|
|
{
|
|
|
|
// keep Ack block and drop some ranges
|
|
|
|
ackBlockSent = true;
|
|
|
|
packet->payloadSize = m_MaxPayloadSize - len;
|
|
|
|
if (packet->payloadSize & 0x01) packet->payloadSize--; // make it even
|
|
|
|
htobe16buf (packet->payload + 1, packet->payloadSize - 3); // new block size
|
|
|
|
}
|
|
|
|
else // drop Ack block completely
|
|
|
|
packet->payloadSize = 0;
|
|
|
|
// msg fits single packet
|
|
|
|
m_SendQueue.pop_front ();
|
|
|
|
packet->payloadSize += CreateI2NPBlock (packet->payload + packet->payloadSize, m_MaxPayloadSize - packet->payloadSize, std::move (msg));
|
|
|
|
}
|
|
|
|
// send right a way
|
|
|
|
uint32_t packetNum = SendData (packet->payload, packet->payloadSize);
|
|
|
|
packet->sendTime = ts;
|
|
|
|
m_SentPackets.emplace (packetNum, packet);
|
|
|
|
packet = newPacket; // just ack block
|
|
|
|
}
|
|
|
|
};
|
|
|
|
if (packet->payloadSize > ackBlockSize)
|
|
|
|
{
|
|
|
|
// last
|
|
|
|
ackBlockSent = true;
|
|
|
|
if (packet->payloadSize + 16 < m_MaxPayloadSize)
|
|
|
|
packet->payloadSize += CreatePaddingBlock (packet->payload + packet->payloadSize, m_MaxPayloadSize - packet->payloadSize);
|
|
|
|
uint32_t packetNum = SendData (packet->payload, packet->payloadSize, SSU2_FLAG_IMMEDIATE_ACK_REQUESTED);
|
|
|
|
packet->sendTime = ts;
|
|
|
|
m_SentPackets.emplace (packetNum, packet);
|
|
|
|
}
|
|
|
|
return ackBlockSent;
|
|
|
|
}
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
|
|
|
|
bool SSU2Session::SendFragmentedMessage (std::shared_ptr<I2NPMessage> msg)
|
|
|
|
{
|
|
|
|
if (!msg) return false;
|
|
|
|
size_t lastFragmentSize = (msg->GetNTCP2Length () + 3 - m_MaxPayloadSize) % (m_MaxPayloadSize - 8);
|
|
|
|
size_t extraSize = m_MaxPayloadSize - lastFragmentSize;
|
|
|
|
bool ackBlockSent = false;
|
|
|
|
uint32_t msgID;
|
|
|
|
memcpy (&msgID, msg->GetHeader () + I2NP_HEADER_MSGID_OFFSET, 4);
|
|
|
|
auto ts = i2p::util::GetMillisecondsSinceEpoch ();
|
|
|
|
auto packet = m_Server.GetSentPacketsPool ().AcquireShared ();
|
|
|
|
if (extraSize >= 8)
|
|
|
|
{
|
|
|
|
packet->payloadSize = CreateAckBlock (packet->payload, extraSize);
|
|
|
|
ackBlockSent = true;
|
|
|
|
if (packet->payloadSize + 12 < m_MaxPayloadSize)
|
|
|
|
{
|
|
|
|
uint32_t packetNum = SendData (packet->payload, packet->payloadSize);
|
|
|
|
packet->sendTime = ts;
|
|
|
|
m_SentPackets.emplace (packetNum, packet);
|
|
|
|
packet = m_Server.GetSentPacketsPool ().AcquireShared ();
|
|
|
|
}
|
|
|
|
else
|
|
|
|
extraSize -= packet->payloadSize;
|
|
|
|
}
|
|
|
|
size_t offset = extraSize > 0 ? (m_Server.GetRng ()() % extraSize) : 0;
|
|
|
|
if (offset + packet->payloadSize >= m_MaxPayloadSize) offset = 0;
|
|
|
|
auto size = CreateFirstFragmentBlock (packet->payload + packet->payloadSize, m_MaxPayloadSize - offset - packet->payloadSize, msg);
|
|
|
|
if (!size) return false;
|
|
|
|
extraSize -= offset;
|
|
|
|
packet->payloadSize += size;
|
|
|
|
uint32_t firstPacketNum = SendData (packet->payload, packet->payloadSize);
|
|
|
|
packet->sendTime = ts;
|
|
|
|
m_SentPackets.emplace (firstPacketNum, packet);
|
|
|
|
uint8_t fragmentNum = 0;
|
|
|
|
while (msg->offset < msg->len)
|
|
|
|
{
|
|
|
|
offset = extraSize > 0 ? (m_Server.GetRng ()() % extraSize) : 0;
|
|
|
|
packet = m_Server.GetSentPacketsPool ().AcquireShared ();
|
|
|
|
packet->payloadSize = CreateFollowOnFragmentBlock (packet->payload, m_MaxPayloadSize - offset, msg, fragmentNum, msgID);
|
|
|
|
extraSize -= offset;
|
|
|
|
uint8_t flags = 0;
|
|
|
|
if (msg->offset >= msg->len && packet->payloadSize + 16 < m_MaxPayloadSize) // last fragment
|
|
|
|
{
|
|
|
|
packet->payloadSize += CreatePaddingBlock (packet->payload + packet->payloadSize, m_MaxPayloadSize - packet->payloadSize);
|
|
|
|
if (fragmentNum > 2) // 3 or more fragments
|
|
|
|
flags |= SSU2_FLAG_IMMEDIATE_ACK_REQUESTED;
|
|
|
|
}
|
|
|
|
uint32_t followonPacketNum = SendData (packet->payload, packet->payloadSize, flags);
|
|
|
|
packet->sendTime = ts;
|
|
|
|
m_SentPackets.emplace (followonPacketNum, packet);
|
|
|
|
}
|
|
|
|
return ackBlockSent;
|
|
|
|
}
|
|
|
|
|
|
|
|
size_t SSU2Session::Resend (uint64_t ts)
|
|
|
|
{
|
|
|
|
if (ts + SSU2_RESEND_ATTEMPT_MIN_INTERVAL < m_LastResendAttemptTime) return 0;
|
|
|
|
m_LastResendAttemptTime = ts;
|
|
|
|
// resend handshake packet
|
|
|
|
if (m_SentHandshakePacket && ts >= m_SentHandshakePacket->sendTime + SSU2_HANDSHAKE_RESEND_INTERVAL)
|
|
|
|
{
|
|
|
|
LogPrint (eLogDebug, "SSU2: Resending ", (int)m_State);
|
|
|
|
ResendHandshakePacket ();
|
|
|
|
m_SentHandshakePacket->sendTime = ts;
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
// resend data packets
|
|
|
|
if (m_SentPackets.empty ()) return 0;
|
|
|
|
std::map<uint32_t, std::shared_ptr<SSU2SentPacket> > resentPackets;
|
|
|
|
for (auto it = m_SentPackets.begin (); it != m_SentPackets.end (); )
|
|
|
|
if (ts >= it->second->sendTime + (it->second->numResends + 1) * m_RTO)
|
|
|
|
{
|
|
|
|
if (it->second->numResends > SSU2_MAX_NUM_RESENDS)
|
|
|
|
{
|
|
|
|
LogPrint (eLogInfo, "SSU2: Packet was not Acked after ", it->second->numResends, " attempts. Terminate session");
|
|
|
|
m_SentPackets.clear ();
|
|
|
|
m_SendQueue.clear ();
|
|
|
|
SetSendQueueSize (0);
|
|
|
|
RequestTermination (eSSU2TerminationReasonTimeout);
|
|
|
|
return resentPackets.size ();
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
uint32_t packetNum = SendData (it->second->payload, it->second->payloadSize);
|
|
|
|
it->second->numResends++;
|
|
|
|
it->second->sendTime = ts;
|
|
|
|
resentPackets.emplace (packetNum, it->second);
|
|
|
|
it = m_SentPackets.erase (it);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
else
|
|
|
|
it++;
|
|
|
|
if (!resentPackets.empty ())
|
|
|
|
{
|
|
|
|
m_LastResendTime = ts;
|
|
|
|
m_SentPackets.merge (resentPackets);
|
|
|
|
m_WindowSize >>= 1; // /2
|
|
|
|
if (m_WindowSize < SSU2_MIN_WINDOW_SIZE) m_WindowSize = SSU2_MIN_WINDOW_SIZE;
|
|
|
|
return resentPackets.size ();
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::ResendHandshakePacket ()
|
|
|
|
{
|
|
|
|
if (m_SentHandshakePacket)
|
|
|
|
{
|
|
|
|
m_Server.Send (m_SentHandshakePacket->header.buf, 16, m_SentHandshakePacket->headerX, 48,
|
|
|
|
m_SentHandshakePacket->payload, m_SentHandshakePacket->payloadSize, m_RemoteEndpoint);
|
|
|
|
if (m_SessionConfirmedFragment && m_State == eSSU2SessionStateSessionConfirmedSent)
|
|
|
|
// resend second fragment of SessionConfirmed
|
|
|
|
m_Server.Send (m_SessionConfirmedFragment->header.buf, 16,
|
|
|
|
m_SessionConfirmedFragment->payload, m_SessionConfirmedFragment->payloadSize, m_RemoteEndpoint);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
bool SSU2Session::ProcessFirstIncomingMessage (uint64_t connID, uint8_t * buf, size_t len)
|
|
|
|
{
|
|
|
|
// we are Bob
|
|
|
|
m_SourceConnID = connID;
|
|
|
|
Header header;
|
|
|
|
header.h.connID = connID;
|
|
|
|
memcpy (header.buf + 8, buf + 8, 8);
|
|
|
|
header.ll[1] ^= CreateHeaderMask (i2p::context.GetSSU2IntroKey (), buf + (len - 12));
|
|
|
|
switch (header.h.type)
|
|
|
|
{
|
|
|
|
case eSSU2SessionRequest:
|
|
|
|
ProcessSessionRequest (header, buf, len);
|
|
|
|
break;
|
|
|
|
case eSSU2TokenRequest:
|
|
|
|
ProcessTokenRequest (header, buf, len);
|
|
|
|
break;
|
|
|
|
case eSSU2PeerTest:
|
|
|
|
{
|
|
|
|
// TODO: remove later
|
|
|
|
if (len < 32)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: PeerTest message too short ", len);
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
const uint8_t nonce[12] = {0};
|
|
|
|
uint64_t headerX[2];
|
|
|
|
i2p::crypto::ChaCha20 (buf + 16, 16, i2p::context.GetSSU2IntroKey (), nonce, (uint8_t *)headerX);
|
|
|
|
LogPrint (eLogWarning, "SSU2: Unexpected PeerTest message SourceConnID=", connID, " DestConnID=", headerX[0]);
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
case eSSU2HolePunch:
|
|
|
|
LogPrint (eLogDebug, "SSU2: Late HolePunch for ", connID);
|
|
|
|
break;
|
|
|
|
default:
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Unexpected message type ", (int)header.h.type, " from ", m_RemoteEndpoint, " of ", len, " bytes");
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::SendSessionRequest (uint64_t token)
|
|
|
|
{
|
|
|
|
// we are Alice
|
|
|
|
m_EphemeralKeys = i2p::transport::transports.GetNextX25519KeysPair ();
|
|
|
|
m_SentHandshakePacket.reset (new HandshakePacket);
|
|
|
|
auto ts = i2p::util::GetMillisecondsSinceEpoch ();
|
|
|
|
m_SentHandshakePacket->sendTime = ts;
|
|
|
|
|
|
|
|
Header& header = m_SentHandshakePacket->header;
|
|
|
|
uint8_t * headerX = m_SentHandshakePacket->headerX,
|
|
|
|
* payload = m_SentHandshakePacket->payload;
|
|
|
|
// fill packet
|
|
|
|
header.h.connID = m_DestConnID; // dest id
|
|
|
|
RAND_bytes (header.buf + 8, 4); // random packet num
|
|
|
|
header.h.type = eSSU2SessionRequest;
|
|
|
|
header.h.flags[0] = 2; // ver
|
|
|
|
header.h.flags[1] = (uint8_t)i2p::context.GetNetID (); // netID
|
|
|
|
header.h.flags[2] = 0; // flag
|
|
|
|
memcpy (headerX, &m_SourceConnID, 8); // source id
|
|
|
|
memcpy (headerX + 8, &token, 8); // token
|
|
|
|
memcpy (headerX + 16, m_EphemeralKeys->GetPublicKey (), 32); // X
|
|
|
|
// payload
|
|
|
|
payload[0] = eSSU2BlkDateTime;
|
|
|
|
htobe16buf (payload + 1, 4);
|
|
|
|
htobe32buf (payload + 3, (ts + 500)/1000);
|
|
|
|
size_t payloadSize = 7;
|
|
|
|
if (GetRouterStatus () == eRouterStatusFirewalled && m_Address->IsIntroducer ())
|
|
|
|
{
|
|
|
|
if (!m_Server.IsMaxNumIntroducers (m_RemoteEndpoint.address ().is_v4 ()) ||
|
|
|
|
m_Server.GetRng ()() & 0x01) // request tag with probability 1/2 if we have enough introducers
|
|
|
|
{
|
|
|
|
// relay tag request
|
|
|
|
payload[payloadSize] = eSSU2BlkRelayTagRequest;
|
|
|
|
memset (payload + payloadSize + 1, 0, 2); // size = 0
|
|
|
|
payloadSize += 3;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
payloadSize += CreatePaddingBlock (payload + payloadSize, 40 - payloadSize, 1);
|
|
|
|
// KDF for session request
|
|
|
|
m_NoiseState->MixHash ({ {header.buf, 16}, {headerX, 16} }); // h = SHA256(h || header)
|
|
|
|
m_NoiseState->MixHash (m_EphemeralKeys->GetPublicKey (), 32); // h = SHA256(h || aepk);
|
|
|
|
uint8_t sharedSecret[32];
|
|
|
|
m_EphemeralKeys->Agree (m_Address->s, sharedSecret);
|
|
|
|
m_NoiseState->MixKey (sharedSecret);
|
|
|
|
// encrypt
|
|
|
|
const uint8_t nonce[12] = {0}; // always 0
|
|
|
|
i2p::crypto::AEADChaCha20Poly1305 (payload, payloadSize, m_NoiseState->m_H, 32, m_NoiseState->m_CK + 32, nonce, payload, payloadSize + 16, true);
|
|
|
|
payloadSize += 16;
|
|
|
|
header.ll[0] ^= CreateHeaderMask (m_Address->i, payload + (payloadSize - 24));
|
|
|
|
header.ll[1] ^= CreateHeaderMask (m_Address->i, payload + (payloadSize - 12));
|
|
|
|
i2p::crypto::ChaCha20 (headerX, 48, m_Address->i, nonce, headerX);
|
|
|
|
m_NoiseState->MixHash (payload, payloadSize); // h = SHA256(h || encrypted payload from Session Request) for SessionCreated
|
|
|
|
m_SentHandshakePacket->payloadSize = payloadSize;
|
|
|
|
// send
|
|
|
|
if (m_State == eSSU2SessionStateTokenReceived || m_Server.AddPendingOutgoingSession (shared_from_this ()))
|
|
|
|
{
|
|
|
|
m_State = eSSU2SessionStateSessionRequestSent;
|
|
|
|
m_HandshakeInterval = ts;
|
|
|
|
m_Server.Send (header.buf, 16, headerX, 48, payload, payloadSize, m_RemoteEndpoint);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: SessionRequest request to ", m_RemoteEndpoint, " already pending");
|
|
|
|
Terminate ();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::ProcessSessionRequest (Header& header, uint8_t * buf, size_t len)
|
|
|
|
{
|
|
|
|
// we are Bob
|
|
|
|
if (len < 88)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: SessionRequest message too short ", len);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
const uint8_t nonce[12] = {0};
|
|
|
|
uint8_t headerX[48];
|
|
|
|
i2p::crypto::ChaCha20 (buf + 16, 48, i2p::context.GetSSU2IntroKey (), nonce, headerX);
|
|
|
|
memcpy (&m_DestConnID, headerX, 8);
|
|
|
|
uint64_t token;
|
|
|
|
memcpy (&token, headerX + 8, 8);
|
|
|
|
if (!token || token != m_Server.GetIncomingToken (m_RemoteEndpoint))
|
|
|
|
{
|
|
|
|
LogPrint (eLogDebug, "SSU2: SessionRequest token mismatch. Retry");
|
|
|
|
SendRetry ();
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
// KDF for session request
|
|
|
|
m_NoiseState->MixHash ( { {header.buf, 16}, {headerX, 16} } ); // h = SHA256(h || header)
|
|
|
|
m_NoiseState->MixHash (headerX + 16, 32); // h = SHA256(h || aepk);
|
|
|
|
uint8_t sharedSecret[32];
|
|
|
|
i2p::context.GetSSU2StaticKeys ().Agree (headerX + 16, sharedSecret);
|
|
|
|
m_NoiseState->MixKey (sharedSecret);
|
|
|
|
// decrypt
|
|
|
|
uint8_t * payload = buf + 64;
|
|
|
|
std::vector<uint8_t> decryptedPayload(len - 80);
|
|
|
|
if (!i2p::crypto::AEADChaCha20Poly1305 (payload, len - 80, m_NoiseState->m_H, 32,
|
|
|
|
m_NoiseState->m_CK + 32, nonce, decryptedPayload.data (), decryptedPayload.size (), false))
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: SessionRequest AEAD verification failed ");
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
m_NoiseState->MixHash (payload, len - 64); // h = SHA256(h || encrypted payload from Session Request) for SessionCreated
|
|
|
|
// payload
|
|
|
|
m_State = eSSU2SessionStateSessionRequestReceived;
|
|
|
|
HandlePayload (decryptedPayload.data (), decryptedPayload.size ());
|
|
|
|
|
|
|
|
if (m_TerminationReason == eSSU2TerminationReasonNormalClose)
|
|
|
|
{
|
|
|
|
m_Server.AddSession (shared_from_this ());
|
|
|
|
SendSessionCreated (headerX + 16);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
SendRetry ();
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::SendSessionCreated (const uint8_t * X)
|
|
|
|
{
|
|
|
|
// we are Bob
|
|
|
|
m_EphemeralKeys = i2p::transport::transports.GetNextX25519KeysPair ();
|
|
|
|
m_SentHandshakePacket.reset (new HandshakePacket);
|
|
|
|
auto ts = i2p::util::GetMillisecondsSinceEpoch ();
|
|
|
|
m_SentHandshakePacket->sendTime = ts;
|
|
|
|
|
|
|
|
uint8_t kh2[32];
|
|
|
|
i2p::crypto::HKDF (m_NoiseState->m_CK, nullptr, 0, "SessCreateHeader", kh2, 32); // k_header_2 = HKDF(chainKey, ZEROLEN, "SessCreateHeader", 32)
|
|
|
|
// fill packet
|
|
|
|
Header& header = m_SentHandshakePacket->header;
|
|
|
|
uint8_t * headerX = m_SentHandshakePacket->headerX,
|
|
|
|
* payload = m_SentHandshakePacket->payload;
|
|
|
|
header.h.connID = m_DestConnID; // dest id
|
|
|
|
RAND_bytes (header.buf + 8, 4); // random packet num
|
|
|
|
header.h.type = eSSU2SessionCreated;
|
|
|
|
header.h.flags[0] = 2; // ver
|
|
|
|
header.h.flags[1] = (uint8_t)i2p::context.GetNetID (); // netID
|
|
|
|
header.h.flags[2] = 0; // flag
|
|
|
|
memcpy (headerX, &m_SourceConnID, 8); // source id
|
|
|
|
memset (headerX + 8, 0, 8); // token = 0
|
|
|
|
memcpy (headerX + 16, m_EphemeralKeys->GetPublicKey (), 32); // Y
|
|
|
|
// payload
|
|
|
|
size_t maxPayloadSize = m_MaxPayloadSize - 48;
|
|
|
|
payload[0] = eSSU2BlkDateTime;
|
|
|
|
htobe16buf (payload + 1, 4);
|
|
|
|
htobe32buf (payload + 3, (ts + 500)/1000);
|
|
|
|
size_t payloadSize = 7;
|
|
|
|
payloadSize += CreateAddressBlock (payload + payloadSize, maxPayloadSize - payloadSize, m_RemoteEndpoint);
|
|
|
|
if (m_RelayTag)
|
|
|
|
{
|
|
|
|
payload[payloadSize] = eSSU2BlkRelayTag;
|
|
|
|
htobe16buf (payload + payloadSize + 1, 4);
|
|
|
|
htobe32buf (payload + payloadSize + 3, m_RelayTag);
|
|
|
|
payloadSize += 7;
|
|
|
|
}
|
|
|
|
auto token = m_Server.NewIncomingToken (m_RemoteEndpoint);
|
|
|
|
if (ts + SSU2_TOKEN_EXPIRATION_THRESHOLD > token.second) // not expired?
|
|
|
|
{
|
|
|
|
payload[payloadSize] = eSSU2BlkNewToken;
|
|
|
|
htobe16buf (payload + payloadSize + 1, 12);
|
|
|
|
htobe32buf (payload + payloadSize + 3, token.second - SSU2_TOKEN_EXPIRATION_THRESHOLD); // expires
|
|
|
|
memcpy (payload + payloadSize + 7, &token.first, 8); // token
|
|
|
|
payloadSize += 15;
|
|
|
|
}
|
|
|
|
payloadSize += CreatePaddingBlock (payload + payloadSize, maxPayloadSize - payloadSize);
|
|
|
|
// KDF for SessionCreated
|
|
|
|
m_NoiseState->MixHash ( { {header.buf, 16}, {headerX, 16} } ); // h = SHA256(h || header)
|
|
|
|
m_NoiseState->MixHash (headerX + 16, 32); // h = SHA256(h || bepk);
|
|
|
|
uint8_t sharedSecret[32];
|
|
|
|
m_EphemeralKeys->Agree (X, sharedSecret);
|
|
|
|
m_NoiseState->MixKey (sharedSecret);
|
|
|
|
// encrypt
|
|
|
|
const uint8_t nonce[12] = {0}; // always zero
|
|
|
|
i2p::crypto::AEADChaCha20Poly1305 (payload, payloadSize, m_NoiseState->m_H, 32, m_NoiseState->m_CK + 32, nonce, payload, payloadSize + 16, true);
|
|
|
|
payloadSize += 16;
|
|
|
|
m_NoiseState->MixHash (payload, payloadSize); // h = SHA256(h || encrypted Noise payload from Session Created)
|
|
|
|
header.ll[0] ^= CreateHeaderMask (i2p::context.GetSSU2IntroKey (), payload + (payloadSize - 24));
|
|
|
|
header.ll[1] ^= CreateHeaderMask (kh2, payload + (payloadSize - 12));
|
|
|
|
i2p::crypto::ChaCha20 (headerX, 48, kh2, nonce, headerX);
|
|
|
|
m_State = eSSU2SessionStateSessionCreatedSent;
|
|
|
|
m_SentHandshakePacket->payloadSize = payloadSize;
|
|
|
|
// send
|
|
|
|
m_HandshakeInterval = ts;
|
|
|
|
m_Server.Send (header.buf, 16, headerX, 48, payload, payloadSize, m_RemoteEndpoint);
|
|
|
|
}
|
|
|
|
|
|
|
|
bool SSU2Session::ProcessSessionCreated (uint8_t * buf, size_t len)
|
|
|
|
{
|
|
|
|
// we are Alice
|
|
|
|
Header header;
|
|
|
|
memcpy (header.buf, buf, 16);
|
|
|
|
header.ll[0] ^= CreateHeaderMask (m_Address->i, buf + (len - 24));
|
|
|
|
uint8_t kh2[32];
|
|
|
|
i2p::crypto::HKDF (m_NoiseState->m_CK, nullptr, 0, "SessCreateHeader", kh2, 32); // k_header_2 = HKDF(chainKey, ZEROLEN, "SessCreateHeader", 32)
|
|
|
|
header.ll[1] ^= CreateHeaderMask (kh2, buf + (len - 12));
|
|
|
|
if (header.h.type != eSSU2SessionCreated)
|
|
|
|
// this situation is valid, because it might be Retry with different encryption
|
|
|
|
return false;
|
|
|
|
if (len < 80)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: SessionCreated message too short ", len);
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
m_HandshakeInterval = i2p::util::GetMillisecondsSinceEpoch () - m_HandshakeInterval;
|
|
|
|
const uint8_t nonce[12] = {0};
|
|
|
|
uint8_t headerX[48];
|
|
|
|
i2p::crypto::ChaCha20 (buf + 16, 48, kh2, nonce, headerX);
|
|
|
|
// KDF for SessionCreated
|
|
|
|
m_NoiseState->MixHash ( { {header.buf, 16}, {headerX, 16} } ); // h = SHA256(h || header)
|
|
|
|
m_NoiseState->MixHash (headerX + 16, 32); // h = SHA256(h || bepk);
|
|
|
|
uint8_t sharedSecret[32];
|
|
|
|
m_EphemeralKeys->Agree (headerX + 16, sharedSecret);
|
|
|
|
m_NoiseState->MixKey (sharedSecret);
|
|
|
|
// decrypt
|
|
|
|
uint8_t * payload = buf + 64;
|
|
|
|
std::vector<uint8_t> decryptedPayload(len - 80);
|
|
|
|
if (!i2p::crypto::AEADChaCha20Poly1305 (payload, len - 80, m_NoiseState->m_H, 32,
|
|
|
|
m_NoiseState->m_CK + 32, nonce, decryptedPayload.data (), decryptedPayload.size (), false))
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: SessionCreated AEAD verification failed ");
|
|
|
|
if (GetRemoteIdentity ())
|
|
|
|
i2p::data::netdb.SetUnreachable (GetRemoteIdentity ()->GetIdentHash (), true); // assume wrong s key
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
m_NoiseState->MixHash (payload, len - 64); // h = SHA256(h || encrypted payload from SessionCreated) for SessionConfirmed
|
|
|
|
// payload
|
|
|
|
m_State = eSSU2SessionStateSessionCreatedReceived;
|
|
|
|
HandlePayload (decryptedPayload.data (), decryptedPayload.size ());
|
|
|
|
|
|
|
|
m_Server.AddSession (shared_from_this ());
|
|
|
|
AdjustMaxPayloadSize ();
|
|
|
|
SendSessionConfirmed (headerX + 16);
|
|
|
|
KDFDataPhase (m_KeyDataSend, m_KeyDataReceive);
|
|
|
|
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::SendSessionConfirmed (const uint8_t * Y)
|
|
|
|
{
|
|
|
|
// we are Alice
|
|
|
|
m_SentHandshakePacket.reset (new HandshakePacket);
|
|
|
|
m_SentHandshakePacket->sendTime = i2p::util::GetMillisecondsSinceEpoch ();
|
|
|
|
|
|
|
|
uint8_t kh2[32];
|
|
|
|
i2p::crypto::HKDF (m_NoiseState->m_CK, nullptr, 0, "SessionConfirmed", kh2, 32); // k_header_2 = HKDF(chainKey, ZEROLEN, "SessionConfirmed", 32)
|
|
|
|
// fill packet
|
|
|
|
Header& header = m_SentHandshakePacket->header;
|
|
|
|
header.h.connID = m_DestConnID; // dest id
|
|
|
|
header.h.packetNum = 0; // always zero
|
|
|
|
header.h.type = eSSU2SessionConfirmed;
|
|
|
|
memset (header.h.flags, 0, 3);
|
|
|
|
header.h.flags[0] = 1; // frag, total fragments always 1
|
|
|
|
// payload
|
|
|
|
size_t maxPayloadSize = m_MaxPayloadSize - 48; // for part 2, 48 is part1
|
|
|
|
uint8_t * payload = m_SentHandshakePacket->payload;
|
|
|
|
size_t payloadSize = CreateRouterInfoBlock (payload, maxPayloadSize, i2p::context.CopyRouterInfoBuffer ());
|
|
|
|
if (!payloadSize)
|
|
|
|
{
|
|
|
|
// split by two fragments
|
|
|
|
maxPayloadSize += m_MaxPayloadSize;
|
|
|
|
payloadSize = CreateRouterInfoBlock (payload, maxPayloadSize, i2p::context.CopyRouterInfoBuffer ());
|
|
|
|
header.h.flags[0] = 0x02; // frag 0, total fragments 2
|
|
|
|
// TODO: check if we need more fragments
|
|
|
|
}
|
|
|
|
if (payloadSize < maxPayloadSize)
|
|
|
|
payloadSize += CreatePaddingBlock (payload + payloadSize, maxPayloadSize - payloadSize);
|
|
|
|
// KDF for Session Confirmed part 1
|
|
|
|
m_NoiseState->MixHash (header.buf, 16); // h = SHA256(h || header)
|
|
|
|
// Encrypt part 1
|
|
|
|
uint8_t * part1 = m_SentHandshakePacket->headerX;
|
|
|
|
uint8_t nonce[12];
|
|
|
|
CreateNonce (1, nonce); // always one
|
|
|
|
i2p::crypto::AEADChaCha20Poly1305 (i2p::context.GetSSU2StaticPublicKey (), 32, m_NoiseState->m_H, 32, m_NoiseState->m_CK + 32, nonce, part1, 48, true);
|
|
|
|
m_NoiseState->MixHash (part1, 48); // h = SHA256(h || ciphertext);
|
|
|
|
// KDF for Session Confirmed part 2
|
|
|
|
uint8_t sharedSecret[32];
|
|
|
|
i2p::context.GetSSU2StaticKeys ().Agree (Y, sharedSecret);
|
|
|
|
m_NoiseState->MixKey (sharedSecret);
|
|
|
|
// Encrypt part2
|
|
|
|
memset (nonce, 0, 12); // always zero
|
|
|
|
i2p::crypto::AEADChaCha20Poly1305 (payload, payloadSize, m_NoiseState->m_H, 32, m_NoiseState->m_CK + 32, nonce, payload, payloadSize + 16, true);
|
|
|
|
payloadSize += 16;
|
|
|
|
m_NoiseState->MixHash (payload, payloadSize); // h = SHA256(h || ciphertext);
|
|
|
|
m_SentHandshakePacket->payloadSize = payloadSize;
|
|
|
|
if (header.h.flags[0] > 1)
|
|
|
|
{
|
|
|
|
if (payloadSize > m_MaxPayloadSize - 48)
|
|
|
|
{
|
|
|
|
payloadSize = m_MaxPayloadSize - 48 - (m_Server.GetRng ()() % 16);
|
|
|
|
if (m_SentHandshakePacket->payloadSize - payloadSize < 24)
|
|
|
|
payloadSize -= 24;
|
|
|
|
}
|
|
|
|
else
|
|
|
|
header.h.flags[0] = 1;
|
|
|
|
}
|
|
|
|
// Encrypt header
|
|
|
|
header.ll[0] ^= CreateHeaderMask (m_Address->i, payload + (payloadSize - 24));
|
|
|
|
header.ll[1] ^= CreateHeaderMask (kh2, payload + (payloadSize - 12));
|
|
|
|
m_State = eSSU2SessionStateSessionConfirmedSent;
|
|
|
|
// send
|
|
|
|
m_Server.Send (header.buf, 16, part1, 48, payload, payloadSize, m_RemoteEndpoint);
|
|
|
|
m_SendPacketNum++;
|
|
|
|
if (m_SentHandshakePacket->payloadSize > payloadSize)
|
|
|
|
{
|
|
|
|
// send second fragment
|
|
|
|
m_SessionConfirmedFragment.reset (new HandshakePacket);
|
|
|
|
Header& header = m_SessionConfirmedFragment->header;
|
|
|
|
header.h.connID = m_DestConnID; // dest id
|
|
|
|
header.h.packetNum = 0;
|
|
|
|
header.h.type = eSSU2SessionConfirmed;
|
|
|
|
memset (header.h.flags, 0, 3);
|
|
|
|
header.h.flags[0] = 0x12; // frag 1, total fragments 2
|
|
|
|
m_SessionConfirmedFragment->payloadSize = m_SentHandshakePacket->payloadSize - payloadSize;
|
|
|
|
memcpy (m_SessionConfirmedFragment->payload, m_SentHandshakePacket->payload + payloadSize, m_SessionConfirmedFragment->payloadSize);
|
|
|
|
m_SentHandshakePacket->payloadSize = payloadSize;
|
|
|
|
header.ll[0] ^= CreateHeaderMask (m_Address->i, m_SessionConfirmedFragment->payload + (m_SessionConfirmedFragment->payloadSize - 24));
|
|
|
|
header.ll[1] ^= CreateHeaderMask (kh2, m_SessionConfirmedFragment->payload + (m_SessionConfirmedFragment->payloadSize - 12));
|
|
|
|
m_Server.Send (header.buf, 16, m_SessionConfirmedFragment->payload, m_SessionConfirmedFragment->payloadSize, m_RemoteEndpoint);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
bool SSU2Session::ProcessSessionConfirmed (uint8_t * buf, size_t len)
|
|
|
|
{
|
|
|
|
// we are Bob
|
|
|
|
Header header;
|
|
|
|
memcpy (header.buf, buf, 16);
|
|
|
|
header.ll[0] ^= CreateHeaderMask (i2p::context.GetSSU2IntroKey (), buf + (len - 24));
|
|
|
|
uint8_t kh2[32];
|
|
|
|
i2p::crypto::HKDF (m_NoiseState->m_CK, nullptr, 0, "SessionConfirmed", kh2, 32); // k_header_2 = HKDF(chainKey, ZEROLEN, "SessionConfirmed", 32)
|
|
|
|
header.ll[1] ^= CreateHeaderMask (kh2, buf + (len - 12));
|
|
|
|
if (header.h.type != eSSU2SessionConfirmed)
|
|
|
|
{
|
|
|
|
LogPrint (eLogInfo, "SSU2: Unexpected message type ", (int)header.h.type, " instead ", (int)eSSU2SessionConfirmed);
|
|
|
|
// TODO: queue up
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
// packet num must be always zero
|
|
|
|
if (header.h.packetNum)
|
|
|
|
{
|
|
|
|
LogPrint (eLogError, "SSU2: Non zero packet number in SessionConfirmed");
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
// check if fragmented
|
|
|
|
uint8_t numFragments = header.h.flags[0] & 0x0F;
|
|
|
|
if (numFragments > 1)
|
|
|
|
{
|
|
|
|
// fragmented
|
|
|
|
if (numFragments > 2)
|
|
|
|
{
|
|
|
|
LogPrint (eLogError, "SSU2: Too many fragments ", (int)numFragments, " in SessionConfirmed from ", m_RemoteEndpoint);
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
if (len < 32)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: SessionConfirmed fragment too short ", len);
|
|
|
|
if (m_SessionConfirmedFragment) m_SessionConfirmedFragment.reset (nullptr);
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
if (!(header.h.flags[0] & 0xF0))
|
|
|
|
{
|
|
|
|
// first fragment
|
|
|
|
if (!m_SessionConfirmedFragment)
|
|
|
|
{
|
|
|
|
m_SessionConfirmedFragment.reset (new HandshakePacket);
|
|
|
|
m_SessionConfirmedFragment->header = header;
|
|
|
|
memcpy (m_SessionConfirmedFragment->payload, buf + 16, len - 16);
|
|
|
|
m_SessionConfirmedFragment->payloadSize = len - 16;
|
|
|
|
return true; // wait for second fragment
|
|
|
|
}
|
|
|
|
else if (m_SessionConfirmedFragment->isSecondFragment)
|
|
|
|
{
|
|
|
|
// we have second fragment
|
|
|
|
m_SessionConfirmedFragment->header = header;
|
|
|
|
memmove (m_SessionConfirmedFragment->payload + (len - 16), m_SessionConfirmedFragment->payload, m_SessionConfirmedFragment->payloadSize);
|
|
|
|
memcpy (m_SessionConfirmedFragment->payload, buf + 16, len - 16);
|
|
|
|
m_SessionConfirmedFragment->payloadSize += (len - 16);
|
|
|
|
m_SessionConfirmedFragment->isSecondFragment = false;
|
|
|
|
buf = m_SessionConfirmedFragment->payload - 16;
|
|
|
|
len = m_SessionConfirmedFragment->payloadSize + 16;
|
|
|
|
}
|
|
|
|
else
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
// second fragment
|
|
|
|
if (!m_SessionConfirmedFragment)
|
|
|
|
{
|
|
|
|
// out of sequence, save it
|
|
|
|
m_SessionConfirmedFragment.reset (new HandshakePacket);
|
|
|
|
memcpy (m_SessionConfirmedFragment->payload, buf + 16, len - 16);
|
|
|
|
m_SessionConfirmedFragment->payloadSize = len - 16;
|
|
|
|
m_SessionConfirmedFragment->isSecondFragment = true;
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
header = m_SessionConfirmedFragment->header;
|
|
|
|
if (m_SessionConfirmedFragment->payloadSize + (len - 16) <= SSU2_MAX_PACKET_SIZE*2)
|
|
|
|
{
|
|
|
|
memcpy (m_SessionConfirmedFragment->payload + m_SessionConfirmedFragment->payloadSize, buf + 16, len - 16);
|
|
|
|
m_SessionConfirmedFragment->payloadSize += (len - 16);
|
|
|
|
}
|
|
|
|
buf = m_SessionConfirmedFragment->payload - 16;
|
|
|
|
len = m_SessionConfirmedFragment->payloadSize + 16;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
if (len < 80)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: SessionConfirmed message too short ", len);
|
|
|
|
if (m_SessionConfirmedFragment) m_SessionConfirmedFragment.reset (nullptr);
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
m_HandshakeInterval = i2p::util::GetMillisecondsSinceEpoch () - m_HandshakeInterval;
|
|
|
|
// KDF for Session Confirmed part 1
|
|
|
|
m_NoiseState->MixHash (header.buf, 16); // h = SHA256(h || header)
|
|
|
|
// decrypt part1
|
|
|
|
uint8_t nonce[12];
|
|
|
|
CreateNonce (1, nonce);
|
|
|
|
uint8_t S[32];
|
|
|
|
if (!i2p::crypto::AEADChaCha20Poly1305 (buf + 16, 32, m_NoiseState->m_H, 32,
|
|
|
|
m_NoiseState->m_CK + 32, nonce, S, 32, false))
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: SessionConfirmed part 1 AEAD verification failed ");
|
|
|
|
if (m_SessionConfirmedFragment) m_SessionConfirmedFragment.reset (nullptr);
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
m_NoiseState->MixHash (buf + 16, 48); // h = SHA256(h || ciphertext);
|
|
|
|
// KDF for Session Confirmed part 2 and data phase
|
|
|
|
uint8_t sharedSecret[32];
|
|
|
|
m_EphemeralKeys->Agree (S, sharedSecret);
|
|
|
|
m_NoiseState->MixKey (sharedSecret);
|
|
|
|
KDFDataPhase (m_KeyDataReceive, m_KeyDataSend);
|
|
|
|
// decrypt part2
|
|
|
|
memset (nonce, 0, 12);
|
|
|
|
uint8_t * payload = buf + 64;
|
|
|
|
std::vector<uint8_t> decryptedPayload(len - 80);
|
|
|
|
if (!i2p::crypto::AEADChaCha20Poly1305 (payload, len - 80, m_NoiseState->m_H, 32,
|
|
|
|
m_NoiseState->m_CK + 32, nonce, decryptedPayload.data (), decryptedPayload.size (), false))
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: SessionConfirmed part 2 AEAD verification failed ");
|
|
|
|
if (m_SessionConfirmedFragment) m_SessionConfirmedFragment.reset (nullptr);
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
m_NoiseState->MixHash (payload, len - 64); // h = SHA256(h || ciphertext);
|
|
|
|
if (m_SessionConfirmedFragment) m_SessionConfirmedFragment.reset (nullptr);
|
|
|
|
// payload
|
|
|
|
// handle RouterInfo block that must be first
|
|
|
|
if (decryptedPayload[0] != eSSU2BlkRouterInfo)
|
|
|
|
{
|
|
|
|
LogPrint (eLogError, "SSU2: SessionConfirmed unexpected first block type ", (int)decryptedPayload[0]);
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
size_t riSize = bufbe16toh (decryptedPayload.data () + 1);
|
|
|
|
if (riSize + 3 > decryptedPayload.size ())
|
|
|
|
{
|
|
|
|
LogPrint (eLogError, "SSU2: SessionConfirmed RouterInfo block is too long ", riSize);
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
LogPrint (eLogDebug, "SSU2: RouterInfo in SessionConfirmed");
|
|
|
|
auto ri = ExtractRouterInfo (decryptedPayload.data () + 3, riSize);
|
|
|
|
if (!ri)
|
|
|
|
{
|
|
|
|
LogPrint (eLogError, "SSU2: SessionConfirmed malformed RouterInfo block");
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
auto ts = i2p::util::GetMillisecondsSinceEpoch();
|
|
|
|
if (ts > ri->GetTimestamp () + i2p::data::NETDB_MIN_EXPIRATION_TIMEOUT*1000LL) // 90 minutes
|
|
|
|
{
|
|
|
|
LogPrint (eLogError, "SSU2: RouterInfo in SessionConfirmed is too old for ", (ts - ri->GetTimestamp ())/1000LL, " seconds");
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
if (ts + i2p::data::NETDB_EXPIRATION_TIMEOUT_THRESHOLD*1000LL < ri->GetTimestamp ()) // 2 minutes
|
|
|
|
{
|
|
|
|
LogPrint (eLogError, "SSU2: RouterInfo in SessionConfirmed is from future for ", (ri->GetTimestamp () - ts)/1000LL, " seconds");
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
// update RouterInfo in netdb
|
|
|
|
auto ri1 = i2p::data::netdb.AddRouterInfo (ri->GetBuffer (), ri->GetBufferLen ()); // ri points to one from netdb now
|
|
|
|
if (!ri1)
|
|
|
|
{
|
|
|
|
LogPrint (eLogError, "SSU2: Couldn't update RouterInfo from SessionConfirmed in netdb");
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
std::shared_ptr<i2p::data::RouterProfile> profile; // not null if older
|
|
|
|
if (ri->GetTimestamp () + i2p::data::NETDB_EXPIRATION_TIMEOUT_THRESHOLD*1000LL < ri1->GetTimestamp ())
|
|
|
|
{
|
|
|
|
// received RouterInfo is older than one in netdb
|
|
|
|
profile = i2p::data::GetRouterProfile (ri->GetIdentHash ()); // retrieve profile
|
|
|
|
if (profile && profile->IsDuplicated ())
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
ri = ri1;
|
|
|
|
|
|
|
|
m_Address = m_RemoteEndpoint.address ().is_v6 () ? ri->GetSSU2V6Address () : ri->GetSSU2V4Address ();
|
|
|
|
if (!m_Address || memcmp (S, m_Address->s, 32))
|
|
|
|
{
|
|
|
|
LogPrint (eLogError, "SSU2: Wrong static key in SessionConfirmed from ", i2p::data::GetIdentHashAbbreviation (ri->GetIdentHash ()));
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
if (m_Address->published && m_RemoteEndpoint.address () != m_Address->host &&
|
|
|
|
(!m_RemoteEndpoint.address ().is_v6 () ||
|
|
|
|
memcmp (m_RemoteEndpoint.address ().to_v6 ().to_bytes ().data (), m_Address->host.to_v6 ().to_bytes ().data (), 8))) // temporary address
|
|
|
|
{
|
|
|
|
if (profile) // older router?
|
|
|
|
profile->Duplicated (); // mark router as duplicated in profile
|
|
|
|
else
|
|
|
|
LogPrint (eLogInfo, "SSU2: Host mismatch between published address ", m_Address->host,
|
|
|
|
" and actual endpoint ", m_RemoteEndpoint.address (), " from ", i2p::data::GetIdentHashAbbreviation (ri->GetIdentHash ()));
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
SetRemoteIdentity (ri->GetRouterIdentity ());
|
|
|
|
AdjustMaxPayloadSize ();
|
|
|
|
m_Server.AddSessionByRouterHash (shared_from_this ()); // we know remote router now
|
|
|
|
m_RemoteTransports = ri->GetCompatibleTransports (false);
|
|
|
|
m_RemotePeerTestTransports = 0;
|
|
|
|
if (ri->IsSSU2PeerTesting (true)) m_RemotePeerTestTransports |= i2p::data::RouterInfo::eSSU2V4;
|
|
|
|
if (ri->IsSSU2PeerTesting (false)) m_RemotePeerTestTransports |= i2p::data::RouterInfo::eSSU2V6;
|
|
|
|
|
|
|
|
// handle other blocks
|
|
|
|
HandlePayload (decryptedPayload.data () + riSize + 3, decryptedPayload.size () - riSize - 3);
|
|
|
|
Established ();
|
|
|
|
|
|
|
|
SendQuickAck ();
|
|
|
|
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::KDFDataPhase (uint8_t * keydata_ab, uint8_t * keydata_ba)
|
|
|
|
{
|
|
|
|
uint8_t keydata[64];
|
|
|
|
i2p::crypto::HKDF (m_NoiseState->m_CK, nullptr, 0, "", keydata); // keydata = HKDF(chainKey, ZEROLEN, "", 64)
|
|
|
|
// ab
|
|
|
|
i2p::crypto::HKDF (keydata, nullptr, 0, "HKDFSSU2DataKeys", keydata_ab); // keydata_ab = HKDF(keydata, ZEROLEN, "HKDFSSU2DataKeys", 64)
|
|
|
|
// ba
|
|
|
|
i2p::crypto::HKDF (keydata + 32, nullptr, 0, "HKDFSSU2DataKeys", keydata_ba); // keydata_ba = HKDF(keydata + 32, ZEROLEN, "HKDFSSU2DataKeys", 64)
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::SendTokenRequest ()
|
|
|
|
{
|
|
|
|
// we are Alice
|
|
|
|
Header header;
|
|
|
|
uint8_t h[32], payload[41];
|
|
|
|
// fill packet
|
|
|
|
header.h.connID = m_DestConnID; // dest id
|
|
|
|
RAND_bytes (header.buf + 8, 4); // random packet num
|
|
|
|
header.h.type = eSSU2TokenRequest;
|
|
|
|
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);
|
|
|
|
memcpy (h + 16, &m_SourceConnID, 8); // source id
|
|
|
|
memset (h + 24, 0, 8); // zero token
|
|
|
|
// payload
|
|
|
|
payload[0] = eSSU2BlkDateTime;
|
|
|
|
htobe16buf (payload + 1, 4);
|
|
|
|
htobe32buf (payload + 3, (i2p::util::GetMillisecondsSinceEpoch () + 500)/1000);
|
|
|
|
size_t payloadSize = 7;
|
|
|
|
payloadSize += CreatePaddingBlock (payload + payloadSize, 25 - payloadSize, 1);
|
|
|
|
// encrypt
|
|
|
|
uint8_t nonce[12];
|
|
|
|
CreateNonce (be32toh (header.h.packetNum), nonce);
|
|
|
|
i2p::crypto::AEADChaCha20Poly1305 (payload, payloadSize, h, 32, m_Address->i, nonce, payload, payloadSize + 16, true);
|
|
|
|
payloadSize += 16;
|
|
|
|
header.ll[0] ^= CreateHeaderMask (m_Address->i, payload + (payloadSize - 24));
|
|
|
|
header.ll[1] ^= CreateHeaderMask (m_Address->i, payload + (payloadSize - 12));
|
|
|
|
memset (nonce, 0, 12);
|
|
|
|
i2p::crypto::ChaCha20 (h + 16, 16, m_Address->i, nonce, h + 16);
|
|
|
|
// send
|
|
|
|
if (m_Server.AddPendingOutgoingSession (shared_from_this ()))
|
|
|
|
m_Server.Send (header.buf, 16, h + 16, 16, payload, payloadSize, m_RemoteEndpoint);
|
|
|
|
else
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: TokenRequest request to ", m_RemoteEndpoint, " already pending");
|
|
|
|
Terminate ();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::ProcessTokenRequest (Header& header, uint8_t * buf, size_t len)
|
|
|
|
{
|
|
|
|
// we are Bob
|
|
|
|
if (len < 48)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Incorrect TokenRequest len ", len);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
uint8_t nonce[12] = {0};
|
|
|
|
uint8_t h[32];
|
|
|
|
memcpy (h, header.buf, 16);
|
|
|
|
i2p::crypto::ChaCha20 (buf + 16, 16, i2p::context.GetSSU2IntroKey (), nonce, h + 16);
|
|
|
|
memcpy (&m_DestConnID, h + 16, 8);
|
|
|
|
// decrypt
|
|
|
|
CreateNonce (be32toh (header.h.packetNum), nonce);
|
|
|
|
uint8_t * payload = buf + 32;
|
|
|
|
if (!i2p::crypto::AEADChaCha20Poly1305 (payload, len - 48, h, 32,
|
|
|
|
i2p::context.GetSSU2IntroKey (), nonce, payload, len - 48, false))
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: TokenRequest AEAD verification failed ");
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
// payload
|
|
|
|
m_State = eSSU2SessionStateTokenRequestReceived;
|
|
|
|
HandlePayload (payload, len - 48);
|
|
|
|
SendRetry ();
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::SendRetry ()
|
|
|
|
{
|
|
|
|
// we are Bob
|
|
|
|
Header header;
|
|
|
|
uint8_t h[32], payload[72];
|
|
|
|
// fill packet
|
|
|
|
header.h.connID = m_DestConnID; // dest id
|
|
|
|
RAND_bytes (header.buf + 8, 4); // random packet num
|
|
|
|
header.h.type = eSSU2Retry;
|
|
|
|
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);
|
|
|
|
memcpy (h + 16, &m_SourceConnID, 8); // source id
|
|
|
|
uint64_t token = 0;
|
|
|
|
if (m_TerminationReason == eSSU2TerminationReasonNormalClose)
|
|
|
|
token = m_Server.GetIncomingToken (m_RemoteEndpoint);
|
|
|
|
memcpy (h + 24, &token, 8); // token
|
|
|
|
// payload
|
|
|
|
payload[0] = eSSU2BlkDateTime;
|
|
|
|
htobe16buf (payload + 1, 4);
|
|
|
|
htobe32buf (payload + 3, (i2p::util::GetMillisecondsSinceEpoch () + 500)/1000);
|
|
|
|
size_t payloadSize = 7;
|
|
|
|
payloadSize += CreateAddressBlock (payload + payloadSize, 56 - payloadSize, m_RemoteEndpoint);
|
|
|
|
if (m_TerminationReason != eSSU2TerminationReasonNormalClose)
|
|
|
|
payloadSize += CreateTerminationBlock (payload + payloadSize, 56 - payloadSize);
|
|
|
|
payloadSize += CreatePaddingBlock (payload + payloadSize, 56 - payloadSize);
|
|
|
|
// encrypt
|
|
|
|
uint8_t nonce[12];
|
|
|
|
CreateNonce (be32toh (header.h.packetNum), nonce);
|
|
|
|
i2p::crypto::AEADChaCha20Poly1305 (payload, payloadSize, h, 32, i2p::context.GetSSU2IntroKey (), nonce, payload, payloadSize + 16, true);
|
|
|
|
payloadSize += 16;
|
|
|
|
header.ll[0] ^= CreateHeaderMask (i2p::context.GetSSU2IntroKey (), payload + (payloadSize - 24));
|
|
|
|
header.ll[1] ^= CreateHeaderMask (i2p::context.GetSSU2IntroKey (), payload + (payloadSize - 12));
|
|
|
|
memset (nonce, 0, 12);
|
|
|
|
i2p::crypto::ChaCha20 (h + 16, 16, i2p::context.GetSSU2IntroKey (), nonce, h + 16);
|
|
|
|
// send
|
|
|
|
m_Server.Send (header.buf, 16, h + 16, 16, payload, payloadSize, m_RemoteEndpoint);
|
|
|
|
}
|
|
|
|
|
|
|
|
bool SSU2Session::ProcessRetry (uint8_t * buf, size_t len)
|
|
|
|
{
|
|
|
|
// we are Alice
|
|
|
|
Header header;
|
|
|
|
memcpy (header.buf, buf, 16);
|
|
|
|
header.ll[0] ^= CreateHeaderMask (m_Address->i, buf + (len - 24));
|
|
|
|
header.ll[1] ^= CreateHeaderMask (m_Address->i, buf + (len - 12));
|
|
|
|
if (header.h.type != eSSU2Retry)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Unexpected message type ", (int)header.h.type, " instead ", (int)eSSU2Retry);
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
if (len < 48)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Retry message too short ", len);
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
uint8_t nonce[12] = {0};
|
|
|
|
uint64_t headerX[2]; // sourceConnID, token
|
|
|
|
i2p::crypto::ChaCha20 (buf + 16, 16, m_Address->i, nonce, (uint8_t *)headerX);
|
|
|
|
uint64_t token = headerX[1];
|
|
|
|
if (token)
|
|
|
|
m_Server.UpdateOutgoingToken (m_RemoteEndpoint, token, i2p::util::GetSecondsSinceEpoch () + SSU2_TOKEN_EXPIRATION_TIMEOUT);
|
|
|
|
// 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,
|
|
|
|
m_Address->i, nonce, payload, len - 48, false))
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Retry AEAD verification failed");
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
m_State = eSSU2SessionStateTokenReceived;
|
|
|
|
HandlePayload (payload, len - 48);
|
|
|
|
if (!token)
|
|
|
|
{
|
|
|
|
// we should handle payload even for zero token to handle Datetime block and adjust clock in case of clock skew
|
|
|
|
LogPrint (eLogWarning, "SSU2: Retry token is zero");
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
InitNoiseXKState1 (*m_NoiseState, m_Address->s); // reset Noise TODO: check state
|
|
|
|
SendSessionRequest (token);
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::SendHolePunch (uint32_t nonce, const boost::asio::ip::udp::endpoint& ep,
|
|
|
|
const uint8_t * introKey, uint64_t token)
|
|
|
|
{
|
|
|
|
// we are Charlie
|
|
|
|
LogPrint (eLogDebug, "SSU2: Sending HolePunch to ", ep);
|
|
|
|
Header header;
|
|
|
|
uint8_t h[32], payload[SSU2_MAX_PACKET_SIZE];
|
|
|
|
// fill packet
|
|
|
|
header.h.connID = htobe64 (((uint64_t)nonce << 32) | nonce); // 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);
|
|
|
|
uint64_t c = ~header.h.connID;
|
|
|
|
memcpy (h + 16, &c, 8); // source id
|
|
|
|
RAND_bytes (h + 24, 8); // token
|
|
|
|
// payload
|
|
|
|
payload[0] = eSSU2BlkDateTime;
|
|
|
|
htobe16buf (payload + 1, 4);
|
|
|
|
htobe32buf (payload + 3, (i2p::util::GetMillisecondsSinceEpoch () + 500)/1000);
|
|
|
|
size_t payloadSize = 7;
|
|
|
|
payloadSize += CreateAddressBlock (payload + payloadSize, m_MaxPayloadSize - payloadSize, ep);
|
|
|
|
payloadSize += CreateRelayResponseBlock (payload + payloadSize, m_MaxPayloadSize - payloadSize,
|
|
|
|
eSSU2RelayResponseCodeAccept, nonce, token, ep.address ().is_v4 ());
|
|
|
|
payloadSize += CreatePaddingBlock (payload + payloadSize, m_MaxPayloadSize - payloadSize);
|
|
|
|
// encrypt
|
|
|
|
uint8_t n[12];
|
|
|
|
CreateNonce (be32toh (header.h.packetNum), n);
|
|
|
|
i2p::crypto::AEADChaCha20Poly1305 (payload, payloadSize, h, 32, introKey, n, payload, payloadSize + 16, true);
|
|
|
|
payloadSize += 16;
|
|
|
|
header.ll[0] ^= CreateHeaderMask (introKey, payload + (payloadSize - 24));
|
|
|
|
header.ll[1] ^= CreateHeaderMask (introKey, payload + (payloadSize - 12));
|
|
|
|
memset (n, 0, 12);
|
|
|
|
i2p::crypto::ChaCha20 (h + 16, 16, introKey, n, h + 16);
|
|
|
|
// send
|
|
|
|
m_Server.Send (header.buf, 16, h + 16, 16, payload, payloadSize, ep);
|
|
|
|
}
|
|
|
|
|
|
|
|
bool SSU2Session::ProcessHolePunch (uint8_t * buf, size_t len)
|
|
|
|
{
|
|
|
|
// we are Alice
|
|
|
|
LogPrint (eLogDebug, "SSU2: HolePunch");
|
|
|
|
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 != eSSU2HolePunch)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Unexpected message type ", (int)header.h.type, " instead ", (int)eSSU2HolePunch);
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
if (len < 48)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: HolePunch 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);
|
|
|
|
m_DestConnID = 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: HolePunch AEAD verification failed ");
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
HandlePayload (payload, len - 48);
|
|
|
|
m_IsDataReceived = false;
|
|
|
|
// connect to Charlie
|
|
|
|
ConnectAfterIntroduction ();
|
|
|
|
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
|
|
|
|
bool SSU2Session::ProcessPeerTest (uint8_t * buf, size_t len)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Unexpected peer test message for this session type");
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
|
|
|
|
uint32_t SSU2Session::SendData (const uint8_t * buf, size_t len, uint8_t flags)
|
|
|
|
{
|
|
|
|
if (len < 8)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Data message payload is too short ", (int)len);
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
Header header;
|
|
|
|
header.h.connID = m_DestConnID;
|
|
|
|
header.h.packetNum = htobe32 (m_SendPacketNum);
|
|
|
|
header.h.type = eSSU2Data;
|
|
|
|
memset (header.h.flags, 0, 3);
|
|
|
|
if (flags) header.h.flags[0] = flags;
|
|
|
|
uint8_t nonce[12];
|
|
|
|
CreateNonce (m_SendPacketNum, nonce);
|
|
|
|
uint8_t payload[SSU2_MAX_PACKET_SIZE];
|
|
|
|
i2p::crypto::AEADChaCha20Poly1305 (buf, len, header.buf, 16, m_KeyDataSend, nonce, payload, SSU2_MAX_PACKET_SIZE, true);
|
|
|
|
header.ll[0] ^= CreateHeaderMask (m_Address->i, payload + (len - 8));
|
|
|
|
header.ll[1] ^= CreateHeaderMask (m_KeyDataSend + 32, payload + (len + 4));
|
|
|
|
m_Server.Send (header.buf, 16, payload, len + 16, m_RemoteEndpoint);
|
|
|
|
m_SendPacketNum++;
|
|
|
|
UpdateNumSentBytes (len + 32);
|
|
|
|
return m_SendPacketNum - 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::ProcessData (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& from)
|
|
|
|
{
|
|
|
|
Header header;
|
|
|
|
header.ll[0] = m_SourceConnID;
|
|
|
|
memcpy (header.buf + 8, buf + 8, 8);
|
|
|
|
header.ll[1] ^= CreateHeaderMask (m_KeyDataReceive + 32, buf + (len - 12));
|
|
|
|
if (header.h.type != eSSU2Data)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Unexpected message type ", (int)header.h.type, " instead ", (int)eSSU2Data);
|
|
|
|
if (IsEstablished ())
|
|
|
|
SendQuickAck (); // in case it was SessionConfirmed
|
|
|
|
else
|
|
|
|
ResendHandshakePacket (); // assume we receive
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
if (from != m_RemoteEndpoint && !i2p::transport::transports.IsInReservedRange (from.address ()))
|
|
|
|
{
|
|
|
|
LogPrint (eLogInfo, "SSU2: Remote endpoint update ", m_RemoteEndpoint, "->", from);
|
|
|
|
m_RemoteEndpoint = from;
|
|
|
|
SendPathChallenge ();
|
|
|
|
}
|
|
|
|
if (len < 32)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Data message too short ", len);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
uint8_t payload[SSU2_MAX_PACKET_SIZE];
|
|
|
|
size_t payloadSize = len - 32;
|
|
|
|
uint32_t packetNum = be32toh (header.h.packetNum);
|
|
|
|
uint8_t nonce[12];
|
|
|
|
CreateNonce (packetNum, nonce);
|
|
|
|
if (!i2p::crypto::AEADChaCha20Poly1305 (buf + 16, payloadSize, header.buf, 16,
|
|
|
|
m_KeyDataReceive, nonce, payload, payloadSize, false))
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Data AEAD verification failed ");
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
UpdateNumReceivedBytes (len);
|
|
|
|
if (header.h.flags[0] & SSU2_FLAG_IMMEDIATE_ACK_REQUESTED) m_IsDataReceived = true;
|
|
|
|
if (!packetNum || UpdateReceivePacketNum (packetNum))
|
|
|
|
HandlePayload (payload, payloadSize);
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::HandlePayload (const uint8_t * buf, size_t len)
|
|
|
|
{
|
|
|
|
size_t offset = 0;
|
|
|
|
while (offset < len)
|
|
|
|
{
|
|
|
|
uint8_t blk = buf[offset];
|
|
|
|
offset++;
|
|
|
|
auto size = bufbe16toh (buf + offset);
|
|
|
|
offset += 2;
|
|
|
|
LogPrint (eLogDebug, "SSU2: Block type ", (int)blk, " of size ", size);
|
|
|
|
if (offset + size > len)
|
|
|
|
{
|
|
|
|
LogPrint (eLogError, "SSU2: Unexpected block length ", size);
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
switch (blk)
|
|
|
|
{
|
|
|
|
case eSSU2BlkDateTime:
|
|
|
|
LogPrint (eLogDebug, "SSU2: Datetime");
|
|
|
|
HandleDateTime (buf + offset, size);
|
|
|
|
break;
|
|
|
|
case eSSU2BlkOptions:
|
|
|
|
LogPrint (eLogDebug, "SSU2: Options");
|
|
|
|
break;
|
|
|
|
case eSSU2BlkRouterInfo:
|
|
|
|
LogPrint (eLogDebug, "SSU2: RouterInfo");
|
|
|
|
HandleRouterInfo (buf + offset, size);
|
|
|
|
break;
|
|
|
|
case eSSU2BlkI2NPMessage:
|
|
|
|
{
|
|
|
|
LogPrint (eLogDebug, "SSU2: I2NP message");
|
|
|
|
auto nextMsg = (buf[offset] == eI2NPTunnelData) ? NewI2NPTunnelMessage (true) : NewI2NPShortMessage ();
|
|
|
|
nextMsg->len = nextMsg->offset + size + 7; // 7 more bytes for full I2NP header
|
|
|
|
memcpy (nextMsg->GetNTCP2Header (), buf + offset, size);
|
|
|
|
nextMsg->FromNTCP2 (); // SSU2 has the same format as NTCP2
|
|
|
|
HandleI2NPMsg (std::move (nextMsg));
|
|
|
|
m_IsDataReceived = true;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
case eSSU2BlkFirstFragment:
|
|
|
|
LogPrint (eLogDebug, "SSU2: First fragment");
|
|
|
|
HandleFirstFragment (buf + offset, size);
|
|
|
|
m_IsDataReceived = true;
|
|
|
|
break;
|
|
|
|
case eSSU2BlkFollowOnFragment:
|
|
|
|
LogPrint (eLogDebug, "SSU2: Follow-on fragment");
|
|
|
|
HandleFollowOnFragment (buf + offset, size);
|
|
|
|
m_IsDataReceived = true;
|
|
|
|
break;
|
|
|
|
case eSSU2BlkTermination:
|
|
|
|
{
|
|
|
|
if (size >= 9)
|
|
|
|
{
|
|
|
|
uint8_t rsn = buf[offset + 8]; // reason
|
|
|
|
LogPrint (eLogDebug, "SSU2: Termination reason=", (int)rsn);
|
|
|
|
if (IsEstablished () && rsn != eSSU2TerminationReasonTerminationReceived)
|
|
|
|
RequestTermination (eSSU2TerminationReasonTerminationReceived);
|
|
|
|
else if (m_State != eSSU2SessionStateTerminated)
|
|
|
|
{
|
|
|
|
if (m_State == eSSU2SessionStateClosing && rsn == eSSU2TerminationReasonTerminationReceived)
|
|
|
|
m_State = eSSU2SessionStateClosingConfirmed;
|
|
|
|
Done ();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
else
|
|
|
|
LogPrint(eLogWarning, "SSU2: Unexpected termination block size ", size);
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
case eSSU2BlkRelayRequest:
|
|
|
|
LogPrint (eLogDebug, "SSU2: RelayRequest");
|
|
|
|
HandleRelayRequest (buf + offset, size);
|
|
|
|
m_IsDataReceived = true;
|
|
|
|
break;
|
|
|
|
case eSSU2BlkRelayResponse:
|
|
|
|
LogPrint (eLogDebug, "SSU2: RelayResponse");
|
|
|
|
HandleRelayResponse (buf + offset, size);
|
|
|
|
m_IsDataReceived = true;
|
|
|
|
break;
|
|
|
|
case eSSU2BlkRelayIntro:
|
|
|
|
LogPrint (eLogDebug, "SSU2: RelayIntro");
|
|
|
|
HandleRelayIntro (buf + offset, size);
|
|
|
|
m_IsDataReceived = true;
|
|
|
|
break;
|
|
|
|
case eSSU2BlkPeerTest:
|
|
|
|
LogPrint (eLogDebug, "SSU2: PeerTest msg=", (int)buf[offset], " code=", (int)buf[offset+1]);
|
|
|
|
HandlePeerTest (buf + offset, size);
|
|
|
|
if (buf[offset] < 5)
|
|
|
|
m_IsDataReceived = true;
|
|
|
|
break;
|
|
|
|
case eSSU2BlkNextNonce:
|
|
|
|
break;
|
|
|
|
case eSSU2BlkAck:
|
|
|
|
LogPrint (eLogDebug, "SSU2: Ack");
|
|
|
|
HandleAck (buf + offset, size);
|
|
|
|
break;
|
|
|
|
case eSSU2BlkAddress:
|
|
|
|
LogPrint (eLogDebug, "SSU2: Address");
|
|
|
|
HandleAddress (buf + offset, size);
|
|
|
|
break;
|
|
|
|
case eSSU2BlkIntroKey:
|
|
|
|
break;
|
|
|
|
case eSSU2BlkRelayTagRequest:
|
|
|
|
LogPrint (eLogDebug, "SSU2: RelayTagRequest");
|
|
|
|
if (!m_RelayTag)
|
|
|
|
{
|
|
|
|
auto addr = FindLocalAddress ();
|
|
|
|
if (addr && addr->IsIntroducer ())
|
|
|
|
{
|
|
|
|
RAND_bytes ((uint8_t *)&m_RelayTag, 4);
|
|
|
|
m_Server.AddRelay (m_RelayTag, shared_from_this ());
|
|
|
|
}
|
|
|
|
}
|
|
|
|
break;
|
|
|
|
case eSSU2BlkRelayTag:
|
|
|
|
LogPrint (eLogDebug, "SSU2: RelayTag");
|
|
|
|
m_RelayTag = bufbe32toh (buf + offset);
|
|
|
|
break;
|
|
|
|
case eSSU2BlkNewToken:
|
|
|
|
{
|
|
|
|
LogPrint (eLogDebug, "SSU2: New token");
|
|
|
|
uint64_t token;
|
|
|
|
memcpy (&token, buf + offset + 4, 8);
|
|
|
|
m_Server.UpdateOutgoingToken (m_RemoteEndpoint, token, bufbe32toh (buf + offset));
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
case eSSU2BlkPathChallenge:
|
|
|
|
LogPrint (eLogDebug, "SSU2: Path challenge");
|
|
|
|
SendPathResponse (buf + offset, size);
|
|
|
|
break;
|
|
|
|
case eSSU2BlkPathResponse:
|
|
|
|
{
|
|
|
|
LogPrint (eLogDebug, "SSU2: Path response");
|
|
|
|
if (m_PathChallenge)
|
|
|
|
{
|
|
|
|
i2p::data::IdentHash hash;
|
|
|
|
SHA256 (buf + offset, size, hash);
|
|
|
|
if (hash == *m_PathChallenge)
|
|
|
|
m_PathChallenge.reset (nullptr);
|
|
|
|
}
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
case eSSU2BlkFirstPacketNumber:
|
|
|
|
break;
|
|
|
|
case eSSU2BlkPadding:
|
|
|
|
LogPrint (eLogDebug, "SSU2: Padding");
|
|
|
|
break;
|
|
|
|
default:
|
|
|
|
LogPrint (eLogWarning, "SSU2: Unknown block type ", (int)blk);
|
|
|
|
}
|
|
|
|
offset += size;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::HandleDateTime (const uint8_t * buf, size_t len)
|
|
|
|
{
|
|
|
|
int64_t offset = (int64_t)i2p::util::GetSecondsSinceEpoch () - (int64_t)bufbe32toh (buf);
|
|
|
|
switch (m_State)
|
|
|
|
{
|
|
|
|
case eSSU2SessionStateSessionRequestReceived:
|
|
|
|
case eSSU2SessionStateTokenRequestReceived:
|
|
|
|
case eSSU2SessionStateEstablished:
|
|
|
|
if (std::abs (offset) > SSU2_CLOCK_SKEW)
|
|
|
|
m_TerminationReason = eSSU2TerminationReasonClockSkew;
|
|
|
|
break;
|
|
|
|
case eSSU2SessionStateSessionCreatedReceived:
|
|
|
|
case eSSU2SessionStateTokenReceived:
|
|
|
|
if ((m_RemoteEndpoint.address ().is_v4 () && i2p::context.GetTesting ()) ||
|
|
|
|
(m_RemoteEndpoint.address ().is_v6 () && i2p::context.GetTestingV6 ()))
|
|
|
|
{
|
|
|
|
if (m_Server.IsSyncClockFromPeers ())
|
|
|
|
{
|
|
|
|
if (std::abs (offset) > SSU2_CLOCK_THRESHOLD)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Time offset ", offset, " from ", m_RemoteEndpoint);
|
|
|
|
m_Server.AdjustTimeOffset (-offset, GetRemoteIdentity ());
|
|
|
|
}
|
|
|
|
else
|
|
|
|
m_Server.AdjustTimeOffset (0, nullptr);
|
|
|
|
}
|
|
|
|
else if (std::abs (offset) > SSU2_CLOCK_SKEW)
|
|
|
|
{
|
|
|
|
LogPrint (eLogError, "SSU2: Clock skew detected ", offset, ". Check your clock");
|
|
|
|
i2p::context.SetError (eRouterErrorClockSkew);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
break;
|
|
|
|
default: ;
|
|
|
|
};
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::HandleRouterInfo (const uint8_t * buf, size_t len)
|
|
|
|
{
|
|
|
|
if (len < 2) return;
|
|
|
|
// not from SessionConfirmed, we must add it instantly to use in next block
|
|
|
|
std::shared_ptr<const i2p::data::RouterInfo> newRi;
|
|
|
|
if (buf[0] & SSU2_ROUTER_INFO_FLAG_GZIP) // compressed?
|
|
|
|
{
|
|
|
|
auto ri = ExtractRouterInfo (buf, len);
|
|
|
|
if (ri)
|
|
|
|
newRi = i2p::data::netdb.AddRouterInfo (ri->GetBuffer (), ri->GetBufferLen ());
|
|
|
|
}
|
|
|
|
else // use buffer directly. TODO: handle frag
|
|
|
|
newRi = i2p::data::netdb.AddRouterInfo (buf + 2, len - 2);
|
|
|
|
|
|
|
|
if (newRi)
|
|
|
|
{
|
|
|
|
auto remoteIdentity = GetRemoteIdentity ();
|
|
|
|
if (remoteIdentity && remoteIdentity->GetIdentHash () == newRi->GetIdentHash ())
|
|
|
|
{
|
|
|
|
// peer's RouterInfo update
|
|
|
|
SetRemoteIdentity (newRi->GetIdentity ());
|
|
|
|
auto address = m_RemoteEndpoint.address ().is_v6 () ? newRi->GetSSU2V6Address () : newRi->GetSSU2V4Address ();
|
|
|
|
if (address)
|
|
|
|
{
|
|
|
|
m_Address = address;
|
|
|
|
if (IsOutgoing () && m_RelayTag && !address->IsIntroducer ())
|
|
|
|
m_RelayTag = 0; // not longer introducer
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::HandleAck (const uint8_t * buf, size_t len)
|
|
|
|
{
|
|
|
|
if (m_State == eSSU2SessionStateSessionConfirmedSent)
|
|
|
|
{
|
|
|
|
Established ();
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
if (m_SentPackets.empty ()) return;
|
|
|
|
if (len < 5) return;
|
|
|
|
// acnt
|
|
|
|
uint32_t ackThrough = bufbe32toh (buf);
|
|
|
|
uint32_t firstPacketNum = ackThrough > buf[4] ? ackThrough - buf[4] : 0;
|
|
|
|
HandleAckRange (firstPacketNum, ackThrough, i2p::util::GetMillisecondsSinceEpoch ()); // acnt
|
|
|
|
// ranges
|
|
|
|
len -= 5;
|
|
|
|
const uint8_t * ranges = buf + 5;
|
|
|
|
while (len > 0 && firstPacketNum && ackThrough - firstPacketNum < SSU2_MAX_NUM_ACK_PACKETS)
|
|
|
|
{
|
|
|
|
uint32_t lastPacketNum = firstPacketNum - 1;
|
|
|
|
if (*ranges > lastPacketNum) break;
|
|
|
|
lastPacketNum -= *ranges; ranges++; // nacks
|
|
|
|
if (*ranges > lastPacketNum + 1) break;
|
|
|
|
firstPacketNum = lastPacketNum - *ranges + 1; ranges++; // acks
|
|
|
|
len -= 2;
|
|
|
|
HandleAckRange (firstPacketNum, lastPacketNum, 0);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::HandleAckRange (uint32_t firstPacketNum, uint32_t lastPacketNum, uint64_t ts)
|
|
|
|
{
|
|
|
|
if (firstPacketNum > lastPacketNum) return;
|
|
|
|
auto it = m_SentPackets.begin ();
|
|
|
|
while (it != m_SentPackets.end () && it->first < firstPacketNum) it++; // find first acked packet
|
|
|
|
if (it == m_SentPackets.end () || it->first > lastPacketNum) return; // not found
|
|
|
|
auto it1 = it;
|
|
|
|
int numPackets = 0;
|
|
|
|
while (it1 != m_SentPackets.end () && it1->first <= lastPacketNum)
|
|
|
|
{
|
|
|
|
if (ts && !it1->second->numResends)
|
|
|
|
{
|
|
|
|
if (ts > it1->second->sendTime)
|
|
|
|
{
|
|
|
|
auto rtt = ts - it1->second->sendTime;
|
|
|
|
if (m_RTT != SSU2_UNKNOWN_RTT)
|
|
|
|
m_RTT = SSU2_RTT_EWMA_ALPHA * rtt + (1.0 - SSU2_RTT_EWMA_ALPHA) * m_RTT;
|
|
|
|
else
|
|
|
|
m_RTT = rtt;
|
|
|
|
m_RTO = m_RTT*SSU2_kAPPA;
|
|
|
|
m_MsgLocalExpirationTimeout = std::max (I2NP_MESSAGE_LOCAL_EXPIRATION_TIMEOUT_MIN,
|
|
|
|
std::min (I2NP_MESSAGE_LOCAL_EXPIRATION_TIMEOUT_MAX,
|
|
|
|
(unsigned int)(m_RTT * 1000 * I2NP_MESSAGE_LOCAL_EXPIRATION_TIMEOUT_FACTOR)));
|
|
|
|
m_MsgLocalSemiExpirationTimeout = m_MsgLocalExpirationTimeout / 2;
|
|
|
|
if (m_RTO < SSU2_MIN_RTO) m_RTO = SSU2_MIN_RTO;
|
|
|
|
if (m_RTO > SSU2_MAX_RTO) m_RTO = SSU2_MAX_RTO;
|
|
|
|
}
|
|
|
|
ts = 0; // update RTT one time per range
|
|
|
|
}
|
|
|
|
it1++;
|
|
|
|
numPackets++;
|
|
|
|
}
|
|
|
|
m_SentPackets.erase (it, it1);
|
|
|
|
if (numPackets > 0)
|
|
|
|
{
|
|
|
|
m_WindowSize += numPackets;
|
|
|
|
if (m_WindowSize > SSU2_MAX_WINDOW_SIZE) m_WindowSize = SSU2_MAX_WINDOW_SIZE;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::HandleAddress (const uint8_t * buf, size_t len)
|
|
|
|
{
|
|
|
|
boost::asio::ip::udp::endpoint ep;
|
|
|
|
if (ExtractEndpoint (buf, len, ep))
|
|
|
|
{
|
|
|
|
LogPrint (eLogInfo, "SSU2: Our external address is ", ep);
|
|
|
|
if (!i2p::transport::transports.IsInReservedRange (ep.address ()))
|
|
|
|
{
|
|
|
|
i2p::context.UpdateAddress (ep.address ());
|
|
|
|
// check our port
|
|
|
|
bool isV4 = ep.address ().is_v4 ();
|
|
|
|
if (ep.port () != m_Server.GetPort (isV4))
|
|
|
|
{
|
|
|
|
LogPrint (eLogInfo, "SSU2: Our port ", ep.port (), " received from ", m_RemoteEndpoint, " is different from ", m_Server.GetPort (isV4));
|
|
|
|
if (isV4)
|
|
|
|
{
|
|
|
|
if (i2p::context.GetTesting ())
|
|
|
|
i2p::context.SetError (eRouterErrorSymmetricNAT);
|
|
|
|
else if (m_State == eSSU2SessionStatePeerTest)
|
|
|
|
i2p::context.SetError (eRouterErrorFullConeNAT);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
if (i2p::context.GetTestingV6 ())
|
|
|
|
i2p::context.SetErrorV6 (eRouterErrorSymmetricNAT);
|
|
|
|
else if (m_State == eSSU2SessionStatePeerTest)
|
|
|
|
i2p::context.SetErrorV6 (eRouterErrorFullConeNAT);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
if (isV4)
|
|
|
|
{
|
|
|
|
if (i2p::context.GetError () == eRouterErrorSymmetricNAT)
|
|
|
|
{
|
|
|
|
if (m_State == eSSU2SessionStatePeerTest)
|
|
|
|
i2p::context.SetStatus (eRouterStatusOK);
|
|
|
|
i2p::context.SetError (eRouterErrorNone);
|
|
|
|
}
|
|
|
|
else if (i2p::context.GetError () == eRouterErrorFullConeNAT)
|
|
|
|
i2p::context.SetError (eRouterErrorNone);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
if (i2p::context.GetErrorV6 () == eRouterErrorSymmetricNAT)
|
|
|
|
{
|
|
|
|
if (m_State == eSSU2SessionStatePeerTest)
|
|
|
|
i2p::context.SetStatusV6 (eRouterStatusOK);
|
|
|
|
i2p::context.SetErrorV6 (eRouterErrorNone);
|
|
|
|
}
|
|
|
|
else if (i2p::context.GetErrorV6 () == eRouterErrorFullConeNAT)
|
|
|
|
i2p::context.SetErrorV6 (eRouterErrorNone);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::HandleFirstFragment (const uint8_t * buf, size_t len)
|
|
|
|
{
|
|
|
|
auto msg = (buf[0] == eI2NPTunnelData) ? NewI2NPTunnelMessage (true) : NewI2NPShortMessage ();
|
|
|
|
uint32_t msgID; memcpy (&msgID, buf + 1, 4);
|
|
|
|
// same format as I2NP message block
|
|
|
|
msg->len = msg->offset + len + 7;
|
|
|
|
memcpy (msg->GetNTCP2Header (), buf, len);
|
|
|
|
std::shared_ptr<SSU2IncompleteMessage> m;
|
|
|
|
bool found = false;
|
|
|
|
auto it = m_IncompleteMessages.find (msgID);
|
|
|
|
if (it != m_IncompleteMessages.end ())
|
|
|
|
{
|
|
|
|
found = true;
|
|
|
|
m = it->second;
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
m = m_Server.GetIncompleteMessagesPool ().AcquireShared ();
|
|
|
|
m_IncompleteMessages.emplace (msgID, m);
|
|
|
|
}
|
|
|
|
m->msg = msg;
|
|
|
|
m->nextFragmentNum = 1;
|
|
|
|
m->lastFragmentInsertTime = i2p::util::GetSecondsSinceEpoch ();
|
|
|
|
if (found && m->ConcatOutOfSequenceFragments ())
|
|
|
|
{
|
|
|
|
// we have all follow-on fragments already
|
|
|
|
m->msg->FromNTCP2 ();
|
|
|
|
HandleI2NPMsg (std::move (m->msg));
|
|
|
|
m_IncompleteMessages.erase (it);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::HandleFollowOnFragment (const uint8_t * buf, size_t len)
|
|
|
|
{
|
|
|
|
if (len < 5) return;
|
|
|
|
uint8_t fragmentNum = buf[0] >> 1;
|
|
|
|
if (!fragmentNum || fragmentNum >= SSU2_MAX_NUM_FRAGMENTS)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Invalid follow-on fragment num ", fragmentNum);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
bool isLast = buf[0] & 0x01;
|
|
|
|
uint32_t msgID; memcpy (&msgID, buf + 1, 4);
|
|
|
|
auto it = m_IncompleteMessages.find (msgID);
|
|
|
|
if (it != m_IncompleteMessages.end ())
|
|
|
|
{
|
|
|
|
if (fragmentNum < it->second->nextFragmentNum) return; // duplicate
|
|
|
|
if (it->second->nextFragmentNum == fragmentNum && fragmentNum < SSU2_MAX_NUM_FRAGMENTS &&
|
|
|
|
it->second->msg)
|
|
|
|
{
|
|
|
|
// in sequence
|
|
|
|
it->second->AttachNextFragment (buf + 5, len - 5);
|
|
|
|
if (isLast)
|
|
|
|
{
|
|
|
|
it->second->msg->FromNTCP2 ();
|
|
|
|
HandleI2NPMsg (std::move (it->second->msg));
|
|
|
|
m_IncompleteMessages.erase (it);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
if (it->second->ConcatOutOfSequenceFragments ())
|
|
|
|
{
|
|
|
|
HandleI2NPMsg (std::move (it->second->msg));
|
|
|
|
m_IncompleteMessages.erase (it);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
it->second->lastFragmentInsertTime = i2p::util::GetSecondsSinceEpoch ();
|
|
|
|
}
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
// follow-on fragment before first fragment
|
|
|
|
auto msg = m_Server.GetIncompleteMessagesPool ().AcquireShared ();
|
|
|
|
msg->nextFragmentNum = 0;
|
|
|
|
it = m_IncompleteMessages.emplace (msgID, msg).first;
|
|
|
|
}
|
|
|
|
// insert out of sequence fragment
|
|
|
|
auto fragment = m_Server.GetFragmentsPool ().AcquireShared ();
|
|
|
|
memcpy (fragment->buf, buf + 5, len -5);
|
|
|
|
fragment->len = len - 5;
|
|
|
|
fragment->fragmentNum = fragmentNum;
|
|
|
|
fragment->isLast = isLast;
|
|
|
|
it->second->AddOutOfSequenceFragment (fragment);
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::HandleRelayRequest (const uint8_t * buf, size_t len)
|
|
|
|
{
|
|
|
|
// we are Bob
|
|
|
|
uint32_t relayTag = bufbe32toh (buf + 5); // relay tag
|
|
|
|
auto session = m_Server.FindRelaySession (relayTag);
|
|
|
|
if (!session)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: RelayRequest session with relay tag ", relayTag, " not found");
|
|
|
|
// send relay response back to Alice
|
|
|
|
uint8_t payload[SSU2_MAX_PACKET_SIZE];
|
|
|
|
size_t payloadSize = CreateRelayResponseBlock (payload, m_MaxPayloadSize,
|
|
|
|
eSSU2RelayResponseCodeBobRelayTagNotFound, bufbe32toh (buf + 1), 0, false);
|
|
|
|
payloadSize += CreatePaddingBlock (payload + payloadSize, m_MaxPayloadSize - payloadSize);
|
|
|
|
SendData (payload, payloadSize);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
auto mts = i2p::util::GetMillisecondsSinceEpoch ();
|
|
|
|
session->m_RelaySessions.emplace (bufbe32toh (buf + 1), // nonce
|
|
|
|
std::make_pair (shared_from_this (), mts/1000) );
|
|
|
|
|
|
|
|
// send relay intro to Charlie
|
|
|
|
auto r = i2p::data::netdb.FindRouter (GetRemoteIdentity ()->GetIdentHash ()); // Alice's RI
|
|
|
|
if (r && (r->IsUnreachable () || !i2p::data::netdb.PopulateRouterInfoBuffer (r))) r = nullptr;
|
|
|
|
if (!r) LogPrint (eLogWarning, "SSU2: RelayRequest Alice's router info not found");
|
|
|
|
|
|
|
|
auto packet = m_Server.GetSentPacketsPool ().AcquireShared ();
|
|
|
|
packet->payloadSize = r ? CreateRouterInfoBlock (packet->payload, m_MaxPayloadSize - len - 32, r) : 0;
|
|
|
|
if (!packet->payloadSize && r)
|
|
|
|
session->SendFragmentedMessage (CreateDatabaseStoreMsg (r));
|
|
|
|
packet->payloadSize += CreateRelayIntroBlock (packet->payload + packet->payloadSize, m_MaxPayloadSize - packet->payloadSize, buf + 1, len -1);
|
|
|
|
if (packet->payloadSize < m_MaxPayloadSize)
|
|
|
|
packet->payloadSize += CreatePaddingBlock (packet->payload + packet->payloadSize, m_MaxPayloadSize - packet->payloadSize);
|
|
|
|
uint32_t packetNum = session->SendData (packet->payload, packet->payloadSize);
|
|
|
|
packet->sendTime = mts;
|
|
|
|
// Charlie always responds with RelayResponse
|
|
|
|
session->m_SentPackets.emplace (packetNum, packet);
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::HandleRelayIntro (const uint8_t * buf, size_t len, int attempts)
|
|
|
|
{
|
|
|
|
// we are Charlie
|
|
|
|
SSU2RelayResponseCode code = eSSU2RelayResponseCodeAccept;
|
|
|
|
uint64_t token = 0;
|
|
|
|
bool isV4 = false;
|
|
|
|
auto r = i2p::data::netdb.FindRouter (buf + 1); // Alice
|
|
|
|
if (r)
|
|
|
|
{
|
|
|
|
SignedData s;
|
|
|
|
s.Insert ((const uint8_t *)"RelayRequestData", 16); // prologue
|
|
|
|
s.Insert (GetRemoteIdentity ()->GetIdentHash (), 32); // bhash
|
|
|
|
s.Insert (i2p::context.GetIdentHash (), 32); // chash
|
|
|
|
s.Insert (buf + 33, 14); // nonce, relay tag, timestamp, ver, asz
|
|
|
|
uint8_t asz = buf[46];
|
|
|
|
s.Insert (buf + 47, asz); // Alice Port, Alice IP
|
|
|
|
if (s.Verify (r->GetIdentity (), buf + 47 + asz))
|
|
|
|
{
|
|
|
|
// send HolePunch
|
|
|
|
boost::asio::ip::udp::endpoint ep;
|
|
|
|
if (ExtractEndpoint (buf + 47, asz, ep))
|
|
|
|
{
|
|
|
|
std::shared_ptr<const i2p::data::RouterInfo::Address> addr;
|
|
|
|
if (!ep.address ().is_unspecified () && ep.port ())
|
|
|
|
addr = ep.address ().is_v6 () ? r->GetSSU2V6Address () : r->GetSSU2V4Address ();
|
|
|
|
if (addr)
|
|
|
|
{
|
|
|
|
if (m_Server.IsSupported (ep.address ()))
|
|
|
|
{
|
|
|
|
token = m_Server.GetIncomingToken (ep);
|
|
|
|
isV4 = ep.address ().is_v4 ();
|
|
|
|
SendHolePunch (bufbe32toh (buf + 33), ep, addr->i, token);
|
|
|
|
m_Server.AddConnectedRecently (ep, i2p::util::GetSecondsSinceEpoch ());
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: RelayIntro unsupported address");
|
|
|
|
code = eSSU2RelayResponseCodeCharlieUnsupportedAddress;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: RelayIntro unknown address");
|
|
|
|
code = eSSU2RelayResponseCodeCharlieAliceIsUnknown;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: RelayIntro can't extract endpoint");
|
|
|
|
code = eSSU2RelayResponseCodeCharlieAliceIsUnknown;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: RelayIntro signature verification failed");
|
|
|
|
code = eSSU2RelayResponseCodeCharlieSignatureFailure;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
else if (!attempts)
|
|
|
|
{
|
|
|
|
// RouterInfo might come in the next packet, try again
|
|
|
|
auto vec = std::make_shared<std::vector<uint8_t> >(len);
|
|
|
|
memcpy (vec->data (), buf, len);
|
|
|
|
auto s = shared_from_this ();
|
|
|
|
m_Server.GetService ().post ([s, vec, attempts]()
|
|
|
|
{
|
|
|
|
LogPrint (eLogDebug, "SSU2: RelayIntro attempt ", attempts + 1);
|
|
|
|
s->HandleRelayIntro (vec->data (), vec->size (), attempts + 1);
|
|
|
|
});
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: RelayIntro unknown router to introduce");
|
|
|
|
code = eSSU2RelayResponseCodeCharlieAliceIsUnknown;
|
|
|
|
}
|
|
|
|
// send relay response to Bob
|
|
|
|
auto packet = m_Server.GetSentPacketsPool ().AcquireShared ();
|
|
|
|
packet->payloadSize = CreateRelayResponseBlock (packet->payload, m_MaxPayloadSize,
|
|
|
|
code, bufbe32toh (buf + 33), token, isV4);
|
|
|
|
packet->payloadSize += CreatePaddingBlock (packet->payload + packet->payloadSize, m_MaxPayloadSize - packet->payloadSize);
|
|
|
|
/*uint32_t packetNum = */SendData (packet->payload, packet->payloadSize);
|
|
|
|
// sometimes Bob doesn't ack this RelayResponse
|
|
|
|
// TODO: uncomment line below once the problem is resolved
|
|
|
|
//packet->sendTime = mts;
|
|
|
|
//m_SentPackets.emplace (packetNum, packet);
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::HandleRelayResponse (const uint8_t * buf, size_t len)
|
|
|
|
{
|
|
|
|
uint32_t nonce = bufbe32toh (buf + 2);
|
|
|
|
if (m_State == eSSU2SessionStateIntroduced)
|
|
|
|
{
|
|
|
|
// HolePunch from Charlie
|
|
|
|
// TODO: verify address and signature
|
|
|
|
// verify nonce
|
|
|
|
if (~htobe64 (((uint64_t)nonce << 32) | nonce) != m_DestConnID)
|
|
|
|
LogPrint (eLogWarning, "SSU2: Relay response nonce mismatch ", nonce, " connID=", m_DestConnID);
|
|
|
|
if (len >= 8)
|
|
|
|
{
|
|
|
|
// new token
|
|
|
|
uint64_t token;
|
|
|
|
memcpy (&token, buf + len - 8, 8);
|
|
|
|
m_Server.UpdateOutgoingToken (m_RemoteEndpoint, token, i2p::util::GetSecondsSinceEpoch () + SSU2_TOKEN_EXPIRATION_TIMEOUT);
|
|
|
|
}
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
auto it = m_RelaySessions.find (nonce);
|
|
|
|
if (it != m_RelaySessions.end ())
|
|
|
|
{
|
|
|
|
if (it->second.first && it->second.first->IsEstablished ())
|
|
|
|
{
|
|
|
|
// we are Bob, message from Charlie
|
|
|
|
auto packet = m_Server.GetSentPacketsPool ().AcquireShared ();
|
|
|
|
uint8_t * payload = packet->payload;
|
|
|
|
payload[0] = eSSU2BlkRelayResponse;
|
|
|
|
htobe16buf (payload + 1, len);
|
|
|
|
memcpy (payload + 3, buf, len); // forward to Alice as is
|
|
|
|
packet->payloadSize = len + 3;
|
|
|
|
packet->payloadSize += CreatePaddingBlock (payload + packet->payloadSize, m_MaxPayloadSize - packet->payloadSize);
|
|
|
|
/*uint32_t packetNum = */it->second.first->SendData (packet->payload, packet->payloadSize);
|
|
|
|
// sometimes Alice doesn't ack this RelayResponse
|
|
|
|
// TODO: uncomment line below once the problem is resolved
|
|
|
|
//packet->sendTime = i2p::util::GetMillisecondsSinceEpoch ();
|
|
|
|
//it->second.first->m_SentPackets.emplace (packetNum, packet);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
// we are Alice, message from Bob
|
|
|
|
if (!buf[1]) // status code accepted?
|
|
|
|
{
|
|
|
|
// verify signature
|
|
|
|
uint8_t csz = buf[11];
|
|
|
|
SignedData s;
|
|
|
|
s.Insert ((const uint8_t *)"RelayAgreementOK", 16); // prologue
|
|
|
|
s.Insert (GetRemoteIdentity ()->GetIdentHash (), 32); // bhash
|
|
|
|
s.Insert (buf + 2, 10 + csz); // nonce, timestamp, ver, csz and Charlie's endpoint
|
|
|
|
if (s.Verify (it->second.first->GetRemoteIdentity (), buf + 12 + csz))
|
|
|
|
{
|
|
|
|
if (it->second.first->m_State == eSSU2SessionStateIntroduced) // HolePunch not received yet
|
|
|
|
{
|
|
|
|
// update Charlie's endpoint
|
|
|
|
if (ExtractEndpoint (buf + 12, csz, it->second.first->m_RemoteEndpoint))
|
|
|
|
{
|
|
|
|
// update token
|
|
|
|
uint64_t token;
|
|
|
|
memcpy (&token, buf + len - 8, 8);
|
|
|
|
m_Server.UpdateOutgoingToken (it->second.first->m_RemoteEndpoint,
|
|
|
|
token, i2p::util::GetSecondsSinceEpoch () + SSU2_TOKEN_EXPIRATION_TIMEOUT);
|
|
|
|
// connect to Charlie, HolePunch will be ignored
|
|
|
|
it->second.first->ConnectAfterIntroduction ();
|
|
|
|
}
|
|
|
|
else
|
|
|
|
LogPrint (eLogWarning, "SSU2: RelayResponse can't extract endpoint");
|
|
|
|
}
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: RelayResponse signature verification failed");
|
|
|
|
it->second.first->Done ();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
LogPrint (eLogInfo, "SSU2: RelayResponse status code=", (int)buf[1], " nonce=", bufbe32toh (buf + 2));
|
|
|
|
it->second.first->Done ();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
m_RelaySessions.erase (it);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
LogPrint (eLogDebug, "SSU2: RelayResponse unknown nonce ", bufbe32toh (buf + 2));
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::HandlePeerTest (const uint8_t * buf, size_t len)
|
|
|
|
{
|
|
|
|
// msgs 1-4
|
|
|
|
if (len < 3) return;
|
|
|
|
uint8_t msg = buf[0];
|
|
|
|
size_t offset = 3; // points to signed data
|
|
|
|
if (msg == 2 || msg == 4) offset += 32; // hash is presented for msg 2 and 4 only
|
|
|
|
if (len < offset + 5) return;
|
|
|
|
auto ts = i2p::util::GetMillisecondsSinceEpoch ();
|
|
|
|
uint32_t nonce = bufbe32toh (buf + offset + 1);
|
|
|
|
switch (msg) // msg
|
|
|
|
{
|
|
|
|
case 1: // Bob from Alice
|
|
|
|
{
|
|
|
|
auto session = m_Server.GetRandomPeerTestSession ((buf[12] == 6) ? i2p::data::RouterInfo::eSSU2V4 : i2p::data::RouterInfo::eSSU2V6,
|
|
|
|
GetRemoteIdentity ()->GetIdentHash ());
|
|
|
|
if (session) // session with Charlie
|
|
|
|
{
|
|
|
|
m_Server.AddPeerTest (nonce, shared_from_this (), ts/1000);
|
|
|
|
auto packet = m_Server.GetSentPacketsPool ().AcquireShared ();
|
|
|
|
// Alice's RouterInfo
|
|
|
|
auto r = i2p::data::netdb.FindRouter (GetRemoteIdentity ()->GetIdentHash ());
|
|
|
|
if (r && (r->IsUnreachable () || !i2p::data::netdb.PopulateRouterInfoBuffer (r))) r = nullptr;
|
|
|
|
packet->payloadSize = r ? CreateRouterInfoBlock (packet->payload, m_MaxPayloadSize - len - 32, r) : 0;
|
|
|
|
if (!packet->payloadSize && r)
|
|
|
|
session->SendFragmentedMessage (CreateDatabaseStoreMsg (r));
|
|
|
|
if (packet->payloadSize + len + 48 > m_MaxPayloadSize)
|
|
|
|
{
|
|
|
|
// doesn't fit one message, send RouterInfo in separate message
|
|
|
|
uint32_t packetNum = session->SendData (packet->payload, packet->payloadSize, SSU2_FLAG_IMMEDIATE_ACK_REQUESTED);
|
|
|
|
packet->sendTime = ts;
|
|
|
|
session->m_SentPackets.emplace (packetNum, packet);
|
|
|
|
packet = m_Server.GetSentPacketsPool ().AcquireShared (); // new packet
|
|
|
|
}
|
|
|
|
// PeerTest to Charlie
|
|
|
|
packet->payloadSize += CreatePeerTestBlock (packet->payload + packet->payloadSize, m_MaxPayloadSize - packet->payloadSize, 2,
|
|
|
|
eSSU2PeerTestCodeAccept, GetRemoteIdentity ()->GetIdentHash (), buf + offset, len - offset);
|
|
|
|
packet->payloadSize += CreatePaddingBlock (packet->payload + packet->payloadSize, m_MaxPayloadSize - packet->payloadSize);
|
|
|
|
uint32_t packetNum = session->SendData (packet->payload, packet->payloadSize, SSU2_FLAG_IMMEDIATE_ACK_REQUESTED);
|
|
|
|
packet->sendTime = ts;
|
|
|
|
session->m_SentPackets.emplace (packetNum, packet);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
// Charlie not found, send error back to Alice
|
|
|
|
auto packet = m_Server.GetSentPacketsPool ().AcquireShared ();
|
|
|
|
uint8_t zeroHash[32] = {0};
|
|
|
|
packet->payloadSize = CreatePeerTestBlock (packet->payload, m_MaxPayloadSize, 4,
|
|
|
|
eSSU2PeerTestCodeBobNoCharlieAvailable, zeroHash, buf + offset, len - offset);
|
|
|
|
packet->payloadSize += CreatePaddingBlock (packet->payload + packet->payloadSize, m_MaxPayloadSize - packet->payloadSize);
|
|
|
|
uint32_t packetNum = SendData (packet->payload, packet->payloadSize);
|
|
|
|
packet->sendTime = ts;
|
|
|
|
m_SentPackets.emplace (packetNum, packet);
|
|
|
|
}
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
case 2: // Charlie from Bob
|
|
|
|
{
|
|
|
|
// sign with Charlie's key
|
|
|
|
uint8_t asz = buf[offset + 9];
|
|
|
|
std::vector<uint8_t> newSignedData (asz + 10 + i2p::context.GetIdentity ()->GetSignatureLen ());
|
|
|
|
memcpy (newSignedData.data (), buf + offset, asz + 10);
|
|
|
|
SignedData s;
|
|
|
|
s.Insert ((const uint8_t *)"PeerTestValidate", 16); // prologue
|
|
|
|
s.Insert (GetRemoteIdentity ()->GetIdentHash (), 32); // bhash
|
|
|
|
s.Insert (buf + 3, 32); // ahash
|
|
|
|
s.Insert (newSignedData.data (), asz + 10); // ver, nonce, ts, asz, Alice's endpoint
|
|
|
|
s.Sign (i2p::context.GetPrivateKeys (), newSignedData.data () + 10 + asz);
|
|
|
|
// send response (msg 3) back and msg 5 if accepted
|
|
|
|
SSU2PeerTestCode code = eSSU2PeerTestCodeAccept;
|
|
|
|
auto r = i2p::data::netdb.FindRouter (buf + 3); // find Alice
|
|
|
|
if (r)
|
|
|
|
{
|
|
|
|
size_t signatureLen = r->GetIdentity ()->GetSignatureLen ();
|
|
|
|
if (len >= offset + asz + 10 + signatureLen)
|
|
|
|
{
|
|
|
|
s.Reset ();
|
|
|
|
s.Insert ((const uint8_t *)"PeerTestValidate", 16); // prologue
|
|
|
|
s.Insert (GetRemoteIdentity ()->GetIdentHash (), 32); // bhash
|
|
|
|
s.Insert (buf + offset, asz + 10); // signed data
|
|
|
|
if (s.Verify (r->GetIdentity (), buf + offset + asz + 10))
|
|
|
|
{
|
|
|
|
if (!m_Server.FindSession (r->GetIdentity ()->GetIdentHash ()))
|
|
|
|
{
|
|
|
|
boost::asio::ip::udp::endpoint ep;
|
|
|
|
std::shared_ptr<const i2p::data::RouterInfo::Address> addr;
|
|
|
|
if (ExtractEndpoint (buf + offset + 10, asz, ep) && !ep.address ().is_unspecified () && ep.port ())
|
|
|
|
addr = r->GetSSU2Address (ep.address ().is_v4 ());
|
|
|
|
if (addr && m_Server.IsSupported (ep.address ()) &&
|
|
|
|
i2p::context.GetRouterInfo ().IsSSU2PeerTesting (ep.address ().is_v4 ()))
|
|
|
|
{
|
|
|
|
if (!m_Server.IsConnectedRecently (ep)) // no alive hole punch
|
|
|
|
{
|
|
|
|
// send msg 5 to Alice
|
|
|
|
auto session = std::make_shared<SSU2PeerTestSession> (m_Server,
|
|
|
|
0, htobe64 (((uint64_t)nonce << 32) | nonce));
|
|
|
|
session->m_RemoteEndpoint = ep; // might be different
|
|
|
|
m_Server.AddSession (session);
|
|
|
|
session->SendPeerTest (5, newSignedData.data (), newSignedData.size (), addr);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
code = eSSU2PeerTestCodeCharlieAliceIsAlreadyConnected;
|
|
|
|
}
|
|
|
|
else
|
|
|
|
code = eSSU2PeerTestCodeCharlieUnsupportedAddress;
|
|
|
|
}
|
|
|
|
else
|
|
|
|
code = eSSU2PeerTestCodeCharlieAliceIsAlreadyConnected;
|
|
|
|
}
|
|
|
|
else
|
|
|
|
code = eSSU2PeerTestCodeCharlieSignatureFailure;
|
|
|
|
}
|
|
|
|
else // maformed message
|
|
|
|
code = eSSU2PeerTestCodeCharlieReasonUnspecified;
|
|
|
|
}
|
|
|
|
else
|
|
|
|
code = eSSU2PeerTestCodeCharlieAliceIsUnknown;
|
|
|
|
// send msg 3 back to Bob
|
|
|
|
auto packet = m_Server.GetSentPacketsPool ().AcquireShared ();
|
|
|
|
packet->payloadSize = CreatePeerTestBlock (packet->payload, m_MaxPayloadSize, 3,
|
|
|
|
code, nullptr, newSignedData.data (), newSignedData.size ());
|
|
|
|
packet->payloadSize += CreatePaddingBlock (packet->payload + packet->payloadSize, m_MaxPayloadSize - packet->payloadSize);
|
|
|
|
uint32_t packetNum = SendData (packet->payload, packet->payloadSize);
|
|
|
|
packet->sendTime = ts;
|
|
|
|
m_SentPackets.emplace (packetNum, packet);
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
case 3: // Bob from Charlie
|
|
|
|
{
|
|
|
|
auto aliceSession = m_Server.GetPeerTest (nonce);
|
|
|
|
if (aliceSession && aliceSession->IsEstablished ())
|
|
|
|
{
|
|
|
|
auto packet = m_Server.GetSentPacketsPool ().AcquireShared ();
|
|
|
|
// Charlie's RouterInfo
|
|
|
|
auto r = i2p::data::netdb.FindRouter (GetRemoteIdentity ()->GetIdentHash ());
|
|
|
|
if (r && (r->IsUnreachable () || !i2p::data::netdb.PopulateRouterInfoBuffer (r))) r = nullptr;
|
|
|
|
packet->payloadSize = r ? CreateRouterInfoBlock (packet->payload, m_MaxPayloadSize - len - 32, r) : 0;
|
|
|
|
if (!packet->payloadSize && r)
|
|
|
|
aliceSession->SendFragmentedMessage (CreateDatabaseStoreMsg (r));
|
|
|
|
if (packet->payloadSize + len + 16 > m_MaxPayloadSize)
|
|
|
|
{
|
|
|
|
// doesn't fit one message, send RouterInfo in separate message
|
|
|
|
uint32_t packetNum = aliceSession->SendData (packet->payload, packet->payloadSize);
|
|
|
|
packet->sendTime = ts;
|
|
|
|
aliceSession->m_SentPackets.emplace (packetNum, packet);
|
|
|
|
packet = m_Server.GetSentPacketsPool ().AcquireShared ();
|
|
|
|
}
|
|
|
|
// PeerTest to Alice
|
|
|
|
packet->payloadSize += CreatePeerTestBlock (packet->payload + packet->payloadSize, m_MaxPayloadSize, 4,
|
|
|
|
(SSU2PeerTestCode)buf[1], GetRemoteIdentity ()->GetIdentHash (), buf + offset, len - offset);
|
|
|
|
if (packet->payloadSize < m_MaxPayloadSize)
|
|
|
|
packet->payloadSize += CreatePaddingBlock (packet->payload + packet->payloadSize, m_MaxPayloadSize - packet->payloadSize);
|
|
|
|
uint32_t packetNum = aliceSession->SendData (packet->payload, packet->payloadSize);
|
|
|
|
packet->sendTime = ts;
|
|
|
|
aliceSession->m_SentPackets.emplace (packetNum, packet);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
LogPrint (eLogDebug, "SSU2: Unknown peer test 3 nonce ", nonce);
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
case 4: // Alice from Bob
|
|
|
|
{
|
|
|
|
auto session = m_Server.GetRequestedPeerTest (nonce);
|
|
|
|
if (session)
|
|
|
|
{
|
|
|
|
if (buf[1] == eSSU2PeerTestCodeAccept)
|
|
|
|
{
|
|
|
|
if (GetRouterStatus () == eRouterStatusUnknown)
|
|
|
|
SetTestingState (true);
|
|
|
|
auto r = i2p::data::netdb.FindRouter (buf + 3); // find Charlie
|
|
|
|
if (r)
|
|
|
|
{
|
|
|
|
uint8_t asz = buf[offset + 9];
|
|
|
|
SignedData s;
|
|
|
|
s.Insert ((const uint8_t *)"PeerTestValidate", 16); // prologue
|
|
|
|
s.Insert (GetRemoteIdentity ()->GetIdentHash (), 32); // bhash
|
|
|
|
s.Insert (i2p::context.GetIdentity ()->GetIdentHash (), 32); // ahash
|
|
|
|
s.Insert (buf + offset, asz + 10); // ver, nonce, ts, asz, Alice's endpoint
|
|
|
|
if (s.Verify (r->GetIdentity (), buf + offset + asz + 10))
|
|
|
|
{
|
|
|
|
session->SetRemoteIdentity (r->GetIdentity ());
|
|
|
|
auto addr = r->GetSSU2Address (m_Address->IsV4 ());
|
|
|
|
if (addr)
|
|
|
|
{
|
|
|
|
if (session->GetMsgNumReceived () >= 5)
|
|
|
|
{
|
|
|
|
// msg 5 already received
|
|
|
|
if (session->GetMsgNumReceived () == 5)
|
|
|
|
{
|
|
|
|
if (!session->IsConnectedRecently ())
|
|
|
|
SetRouterStatus (eRouterStatusOK);
|
|
|
|
// send msg 6
|
|
|
|
session->SendPeerTest (6, buf + offset, len - offset, addr);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
LogPrint (eLogWarning, "SSU2: PeerTest 4 received, but msg ", session->GetMsgNumReceived (), " already received");
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
session->m_Address = addr;
|
|
|
|
if (GetTestingState ())
|
|
|
|
{
|
|
|
|
SetTestingState (false);
|
|
|
|
if (GetRouterStatus () != eRouterStatusFirewalled && addr->IsPeerTesting ())
|
|
|
|
{
|
|
|
|
SetRouterStatus (eRouterStatusFirewalled);
|
|
|
|
session->SetStatusChanged ();
|
|
|
|
if (m_Address->IsV4 ())
|
|
|
|
m_Server.RescheduleIntroducersUpdateTimer ();
|
|
|
|
else
|
|
|
|
m_Server.RescheduleIntroducersUpdateTimerV6 ();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
LogPrint (eLogDebug, "SSU2: Peer test 4 received from ", i2p::data::GetIdentHashAbbreviation (GetRemoteIdentity ()->GetIdentHash ()),
|
|
|
|
" with information about ", i2p::data::GetIdentHashAbbreviation (i2p::data::IdentHash (buf + 3)));
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Peer test 4 address not found");
|
|
|
|
session->Done ();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Peer test 4 signature verification failed");
|
|
|
|
session->Done ();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Peer test 4 router not found");
|
|
|
|
session->Done ();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
LogPrint (eLogInfo, "SSU2: Peer test 4 error code ", (int)buf[1], " from ",
|
|
|
|
i2p::data::GetIdentHashAbbreviation (buf[1] < 64 ? GetRemoteIdentity ()->GetIdentHash () : i2p::data::IdentHash (buf + 3)));
|
|
|
|
if (GetTestingState () && GetRouterStatus () != eRouterStatusFirewalled)
|
|
|
|
SetRouterStatus (eRouterStatusUnknown);
|
|
|
|
session->Done ();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
else
|
|
|
|
LogPrint (eLogDebug, "SSU2: Unknown peer test 4 nonce ", nonce);
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
default:
|
|
|
|
LogPrint (eLogWarning, "SSU2: PeerTest unexpected msg num ", buf[0]);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::HandleI2NPMsg (std::shared_ptr<I2NPMessage>&& msg)
|
|
|
|
{
|
|
|
|
if (!msg) return;
|
|
|
|
uint32_t msgID = msg->GetMsgID ();
|
|
|
|
if (!msg->IsExpired ())
|
|
|
|
{
|
|
|
|
// m_LastActivityTimestamp is updated in ProcessData before
|
|
|
|
if (m_ReceivedI2NPMsgIDs.emplace (msgID, (uint32_t)GetLastActivityTimestamp ()).second)
|
|
|
|
m_Handler.PutNextMessage (std::move (msg));
|
|
|
|
else
|
|
|
|
LogPrint (eLogDebug, "SSU2: Message ", msgID, " already received");
|
|
|
|
}
|
|
|
|
else
|
|
|
|
LogPrint (eLogDebug, "SSU2: Message ", msgID, " expired");
|
|
|
|
}
|
|
|
|
|
|
|
|
bool SSU2Session::ExtractEndpoint (const uint8_t * buf, size_t size, boost::asio::ip::udp::endpoint& ep)
|
|
|
|
{
|
|
|
|
if (size < 2) return false;
|
|
|
|
int port = bufbe16toh (buf);
|
|
|
|
if (size == 6)
|
|
|
|
{
|
|
|
|
boost::asio::ip::address_v4::bytes_type bytes;
|
|
|
|
memcpy (bytes.data (), buf + 2, 4);
|
|
|
|
ep = boost::asio::ip::udp::endpoint (boost::asio::ip::address_v4 (bytes), port);
|
|
|
|
}
|
|
|
|
else if (size == 18)
|
|
|
|
{
|
|
|
|
boost::asio::ip::address_v6::bytes_type bytes;
|
|
|
|
memcpy (bytes.data (), buf + 2, 16);
|
|
|
|
ep = boost::asio::ip::udp::endpoint (boost::asio::ip::address_v6 (bytes), port);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Address size ", int(size), " is not supported");
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
|
|
|
|
size_t SSU2Session::CreateEndpoint (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& ep)
|
|
|
|
{
|
|
|
|
if (len < 6) return 0;
|
|
|
|
htobe16buf (buf, ep.port ());
|
|
|
|
size_t size = 0;
|
|
|
|
if (ep.address ().is_v4 ())
|
|
|
|
{
|
|
|
|
memcpy (buf + 2, ep.address ().to_v4 ().to_bytes ().data (), 4);
|
|
|
|
size = 6;
|
|
|
|
}
|
|
|
|
else if (ep.address ().is_v6 ())
|
|
|
|
{
|
|
|
|
if (len < 18) return 0;
|
|
|
|
memcpy (buf + 2, ep.address ().to_v6 ().to_bytes ().data (), 16);
|
|
|
|
size = 18;
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Wrong address type ", ep.address ().to_string ());
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
return size;
|
|
|
|
}
|
|
|
|
|
|
|
|
std::shared_ptr<const i2p::data::RouterInfo::Address> SSU2Session::FindLocalAddress () const
|
|
|
|
{
|
|
|
|
if (m_Address)
|
|
|
|
return i2p::context.GetRouterInfo ().GetSSU2Address (m_Address->IsV4 ());
|
|
|
|
else if (!m_RemoteEndpoint.address ().is_unspecified ())
|
|
|
|
return i2p::context.GetRouterInfo ().GetSSU2Address (m_RemoteEndpoint.address ().is_v4 ());
|
|
|
|
return nullptr;
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::AdjustMaxPayloadSize ()
|
|
|
|
{
|
|
|
|
auto addr = FindLocalAddress ();
|
|
|
|
if (addr && addr->ssu)
|
|
|
|
{
|
|
|
|
int mtu = addr->ssu->mtu;
|
|
|
|
if (!mtu && addr->IsV4 ()) mtu = SSU2_MAX_PACKET_SIZE;
|
|
|
|
if (m_Address && m_Address->ssu && (!mtu || m_Address->ssu->mtu < mtu))
|
|
|
|
mtu = m_Address->ssu->mtu;
|
|
|
|
if (mtu)
|
|
|
|
{
|
|
|
|
if (mtu < (int)SSU2_MIN_PACKET_SIZE) mtu = SSU2_MIN_PACKET_SIZE;
|
|
|
|
m_MaxPayloadSize = mtu - (addr->IsV6 () ? IPV6_HEADER_SIZE: IPV4_HEADER_SIZE) - UDP_HEADER_SIZE - 32;
|
|
|
|
LogPrint (eLogDebug, "SSU2: Session MTU=", mtu, ", max payload size=", m_MaxPayloadSize);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
RouterStatus SSU2Session::GetRouterStatus () const
|
|
|
|
{
|
|
|
|
if (m_Address)
|
|
|
|
{
|
|
|
|
if (m_Address->IsV4 ())
|
|
|
|
return i2p::context.GetStatus ();
|
|
|
|
if (m_Address->IsV6 ())
|
|
|
|
return i2p::context.GetStatusV6 ();
|
|
|
|
}
|
|
|
|
return eRouterStatusUnknown;
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::SetRouterStatus (RouterStatus status) const
|
|
|
|
{
|
|
|
|
if (m_Address)
|
|
|
|
{
|
|
|
|
if (m_Address->IsV4 ())
|
|
|
|
i2p::context.SetStatus (status);
|
|
|
|
else if (m_Address->IsV6 ())
|
|
|
|
i2p::context.SetStatusV6 (status);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
bool SSU2Session::GetTestingState () const
|
|
|
|
{
|
|
|
|
if (m_Address)
|
|
|
|
{
|
|
|
|
if (m_Address->IsV4 ())
|
|
|
|
return i2p::context.GetTesting ();
|
|
|
|
if (m_Address->IsV6 ())
|
|
|
|
return i2p::context.GetTestingV6 ();
|
|
|
|
}
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::SetTestingState (bool testing) const
|
|
|
|
{
|
|
|
|
if (m_Address)
|
|
|
|
{
|
|
|
|
if (m_Address->IsV4 ())
|
|
|
|
i2p::context.SetTesting (testing);
|
|
|
|
else if (m_Address->IsV6 ())
|
|
|
|
i2p::context.SetTestingV6 (testing);
|
|
|
|
}
|
|
|
|
if (!testing)
|
|
|
|
m_Server.AdjustTimeOffset (0, nullptr); // reset time offset when testing is over
|
|
|
|
}
|
|
|
|
|
|
|
|
size_t SSU2Session::CreateAddressBlock (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& ep)
|
|
|
|
{
|
|
|
|
if (len < 9) return 0;
|
|
|
|
buf[0] = eSSU2BlkAddress;
|
|
|
|
size_t size = CreateEndpoint (buf + 3, len - 3, ep);
|
|
|
|
if (!size) return 0;
|
|
|
|
htobe16buf (buf + 1, size);
|
|
|
|
return size + 3;
|
|
|
|
}
|
|
|
|
|
|
|
|
size_t SSU2Session::CreateRouterInfoBlock (uint8_t * buf, size_t len, std::shared_ptr<const i2p::data::RouterInfo> r)
|
|
|
|
{
|
|
|
|
if (!r || len < 5) return 0;
|
|
|
|
return CreateRouterInfoBlock (buf, len, r->GetSharedBuffer ());
|
|
|
|
}
|
|
|
|
|
|
|
|
size_t SSU2Session::CreateRouterInfoBlock (uint8_t * buf, size_t len, std::shared_ptr<const i2p::data::RouterInfo::Buffer> riBuffer)
|
|
|
|
{
|
|
|
|
if (!riBuffer || len < 5) return 0;
|
|
|
|
buf[0] = eSSU2BlkRouterInfo;
|
|
|
|
size_t size = riBuffer->GetBufferLen ();
|
|
|
|
if (size + 5 < len)
|
|
|
|
{
|
|
|
|
memcpy (buf + 5, riBuffer->data (), size);
|
|
|
|
buf[3] = 0; // flag
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
i2p::data::GzipDeflator deflator;
|
|
|
|
deflator.SetCompressionLevel (9);
|
|
|
|
size = deflator.Deflate (riBuffer->data (), riBuffer->GetBufferLen (), buf + 5, len - 5);
|
|
|
|
if (!size) return 0; // doesn't fit
|
|
|
|
buf[3] = SSU2_ROUTER_INFO_FLAG_GZIP; // flag
|
|
|
|
}
|
|
|
|
htobe16buf (buf + 1, size + 2); // size
|
|
|
|
buf[4] = 1; // frag
|
|
|
|
return size + 5;
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
size_t SSU2Session::CreateAckBlock (uint8_t * buf, size_t len)
|
|
|
|
{
|
|
|
|
if (len < 8) return 0;
|
|
|
|
int maxNumRanges = (len - 8) >> 1;
|
|
|
|
if (maxNumRanges > SSU2_MAX_NUM_ACK_RANGES) maxNumRanges = SSU2_MAX_NUM_ACK_RANGES;
|
|
|
|
buf[0] = eSSU2BlkAck;
|
|
|
|
uint32_t ackThrough = m_OutOfSequencePackets.empty () ? m_ReceivePacketNum : *m_OutOfSequencePackets.rbegin ();
|
|
|
|
htobe32buf (buf + 3, ackThrough); // Ack Through
|
|
|
|
uint16_t acnt = 0;
|
|
|
|
int numRanges = 0;
|
|
|
|
if (ackThrough)
|
|
|
|
{
|
|
|
|
if (m_OutOfSequencePackets.empty ())
|
|
|
|
acnt = std::min ((int)ackThrough, SSU2_MAX_NUM_ACNT); // no gaps
|
|
|
|
else
|
|
|
|
{
|
|
|
|
auto it = m_OutOfSequencePackets.rbegin (); it++; // prev packet num
|
|
|
|
while (it != m_OutOfSequencePackets.rend () && *it == ackThrough - acnt - 1)
|
|
|
|
{
|
|
|
|
acnt++;
|
|
|
|
if (acnt >= SSU2_MAX_NUM_ACK_PACKETS)
|
|
|
|
break;
|
|
|
|
else
|
|
|
|
it++;
|
|
|
|
}
|
|
|
|
// ranges
|
|
|
|
uint32_t lastNum = ackThrough - acnt;
|
|
|
|
if (acnt > SSU2_MAX_NUM_ACNT)
|
|
|
|
{
|
|
|
|
auto d = std::div (acnt - SSU2_MAX_NUM_ACNT, SSU2_MAX_NUM_ACNT);
|
|
|
|
acnt = SSU2_MAX_NUM_ACNT;
|
|
|
|
if (d.quot > maxNumRanges)
|
|
|
|
{
|
|
|
|
d.quot = maxNumRanges;
|
|
|
|
d.rem = 0;
|
|
|
|
}
|
|
|
|
// Acks only ranges for acnt
|
|
|
|
for (int i = 0; i < d.quot; i++)
|
|
|
|
{
|
|
|
|
buf[8 + numRanges*2] = 0; buf[8 + numRanges*2 + 1] = SSU2_MAX_NUM_ACNT; // NACKs 0, Acks 255
|
|
|
|
numRanges++;
|
|
|
|
}
|
|
|
|
if (d.rem > 0)
|
|
|
|
{
|
|
|
|
buf[8 + numRanges*2] = 0; buf[8 + numRanges*2 + 1] = d.rem;
|
|
|
|
numRanges++;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
int numPackets = acnt + numRanges*SSU2_MAX_NUM_ACNT;
|
|
|
|
while (it != m_OutOfSequencePackets.rend () &&
|
|
|
|
numRanges < maxNumRanges && numPackets < SSU2_MAX_NUM_ACK_PACKETS)
|
|
|
|
{
|
|
|
|
if (lastNum - (*it) > SSU2_MAX_NUM_ACNT)
|
|
|
|
{
|
|
|
|
// NACKs only ranges
|
|
|
|
if (lastNum > (*it) + SSU2_MAX_NUM_ACNT*(maxNumRanges - numRanges)) break; // too many NACKs
|
|
|
|
while (lastNum - (*it) > SSU2_MAX_NUM_ACNT)
|
|
|
|
{
|
|
|
|
buf[8 + numRanges*2] = SSU2_MAX_NUM_ACNT; buf[8 + numRanges*2 + 1] = 0; // NACKs 255, Acks 0
|
|
|
|
lastNum -= SSU2_MAX_NUM_ACNT;
|
|
|
|
numRanges++;
|
|
|
|
numPackets += SSU2_MAX_NUM_ACNT;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
// NACKs and Acks ranges
|
|
|
|
buf[8 + numRanges*2] = lastNum - (*it) - 1; // NACKs
|
|
|
|
numPackets += buf[8 + numRanges*2];
|
|
|
|
lastNum = *it; it++;
|
|
|
|
int numAcks = 1;
|
|
|
|
while (it != m_OutOfSequencePackets.rend () && lastNum > 0 && *it == lastNum - 1)
|
|
|
|
{
|
|
|
|
numAcks++; lastNum--;
|
|
|
|
it++;
|
|
|
|
}
|
|
|
|
while (numAcks > SSU2_MAX_NUM_ACNT)
|
|
|
|
{
|
|
|
|
// Acks only ranges
|
|
|
|
buf[8 + numRanges*2 + 1] = SSU2_MAX_NUM_ACNT; // Acks 255
|
|
|
|
numAcks -= SSU2_MAX_NUM_ACNT;
|
|
|
|
numRanges++;
|
|
|
|
numPackets += SSU2_MAX_NUM_ACNT;
|
|
|
|
buf[8 + numRanges*2] = 0; // NACKs 0
|
|
|
|
if (numRanges >= maxNumRanges || numPackets >= SSU2_MAX_NUM_ACK_PACKETS) break;
|
|
|
|
}
|
|
|
|
if (numAcks > SSU2_MAX_NUM_ACNT) numAcks = SSU2_MAX_NUM_ACNT;
|
|
|
|
buf[8 + numRanges*2 + 1] = (uint8_t)numAcks; // Acks
|
|
|
|
numPackets += numAcks;
|
|
|
|
numRanges++;
|
|
|
|
}
|
|
|
|
if (it == m_OutOfSequencePackets.rend () &&
|
|
|
|
numRanges < maxNumRanges && numPackets < SSU2_MAX_NUM_ACK_PACKETS)
|
|
|
|
{
|
|
|
|
// add range between out-of-sequence and received
|
|
|
|
int nacks = *m_OutOfSequencePackets.begin () - m_ReceivePacketNum - 1;
|
|
|
|
if (nacks > 0)
|
|
|
|
{
|
|
|
|
if (nacks > SSU2_MAX_NUM_ACNT) nacks = SSU2_MAX_NUM_ACNT;
|
|
|
|
buf[8 + numRanges*2] = nacks;
|
|
|
|
buf[8 + numRanges*2 + 1] = std::min ((int)m_ReceivePacketNum + 1, SSU2_MAX_NUM_ACNT);
|
|
|
|
numRanges++;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
buf[7] = (uint8_t)acnt; // acnt
|
|
|
|
htobe16buf (buf + 1, 5 + numRanges*2);
|
|
|
|
return 8 + numRanges*2;
|
|
|
|
}
|
|
|
|
|
|
|
|
size_t SSU2Session::CreatePaddingBlock (uint8_t * buf, size_t len, size_t minSize)
|
|
|
|
{
|
|
|
|
if (len < 3 || len < minSize) return 0;
|
|
|
|
size_t paddingSize = m_Server.GetRng ()() & 0x0F; // 0 - 15
|
|
|
|
if (paddingSize + 3 > len) paddingSize = len - 3;
|
|
|
|
else if (paddingSize + 3 < minSize) paddingSize = minSize - 3;
|
|
|
|
buf[0] = eSSU2BlkPadding;
|
|
|
|
htobe16buf (buf + 1, paddingSize);
|
|
|
|
memset (buf + 3, 0, paddingSize);
|
|
|
|
return paddingSize + 3;
|
|
|
|
}
|
|
|
|
|
|
|
|
size_t SSU2Session::CreateI2NPBlock (uint8_t * buf, size_t len, std::shared_ptr<I2NPMessage>&& msg)
|
|
|
|
{
|
|
|
|
msg->ToNTCP2 ();
|
|
|
|
auto msgBuf = msg->GetNTCP2Header ();
|
|
|
|
auto msgLen = msg->GetNTCP2Length ();
|
|
|
|
if (msgLen + 3 > len) msgLen = len - 3;
|
|
|
|
buf[0] = eSSU2BlkI2NPMessage;
|
|
|
|
htobe16buf (buf + 1, msgLen); // size
|
|
|
|
memcpy (buf + 3, msgBuf, msgLen);
|
|
|
|
return msgLen + 3;
|
|
|
|
}
|
|
|
|
|
|
|
|
size_t SSU2Session::CreateFirstFragmentBlock (uint8_t * buf, size_t len, std::shared_ptr<I2NPMessage> msg)
|
|
|
|
{
|
|
|
|
if (len < 12) return 0;
|
|
|
|
msg->ToNTCP2 ();
|
|
|
|
auto msgBuf = msg->GetNTCP2Header ();
|
|
|
|
auto msgLen = msg->GetNTCP2Length ();
|
|
|
|
if (msgLen + 3 <= len) return 0;
|
|
|
|
msgLen = len - 3;
|
|
|
|
buf[0] = eSSU2BlkFirstFragment;
|
|
|
|
htobe16buf (buf + 1, msgLen); // size
|
|
|
|
memcpy (buf + 3, msgBuf, msgLen);
|
|
|
|
msg->offset = (msgBuf - msg->buf) + msgLen;
|
|
|
|
return msgLen + 3;
|
|
|
|
}
|
|
|
|
|
|
|
|
size_t SSU2Session::CreateFollowOnFragmentBlock (uint8_t * buf, size_t len, std::shared_ptr<I2NPMessage> msg, uint8_t& fragmentNum, uint32_t msgID)
|
|
|
|
{
|
|
|
|
if (len < 8) return 0;
|
|
|
|
bool isLast = true;
|
|
|
|
auto msgLen = msg->len - msg->offset;
|
|
|
|
if (msgLen + 8 > len)
|
|
|
|
{
|
|
|
|
msgLen = len - 8;
|
|
|
|
isLast = false;
|
|
|
|
}
|
|
|
|
buf[0] = eSSU2BlkFollowOnFragment;
|
|
|
|
htobe16buf (buf + 1, msgLen + 5); // size
|
|
|
|
fragmentNum++;
|
|
|
|
buf[3] = fragmentNum << 1;
|
|
|
|
if (isLast) buf[3] |= 0x01;
|
|
|
|
memcpy (buf + 4, &msgID, 4);
|
|
|
|
memcpy (buf + 8, msg->buf + msg->offset, msgLen);
|
|
|
|
msg->offset += msgLen;
|
|
|
|
return msgLen + 8;
|
|
|
|
}
|
|
|
|
|
|
|
|
size_t SSU2Session::CreateRelayIntroBlock (uint8_t * buf, size_t len, const uint8_t * introData, size_t introDataLen)
|
|
|
|
{
|
|
|
|
buf[0] = eSSU2BlkRelayIntro;
|
|
|
|
size_t payloadSize = 1/* flag */ + 32/* Alice router hash */ + introDataLen;
|
|
|
|
if (payloadSize + 3 > len) return 0;
|
|
|
|
htobe16buf (buf + 1, payloadSize); // size
|
|
|
|
buf[3] = 0; // flag
|
|
|
|
memcpy (buf + 4, GetRemoteIdentity ()->GetIdentHash (), 32); // Alice router hash
|
|
|
|
memcpy (buf + 36, introData, introDataLen);
|
|
|
|
return payloadSize + 3;
|
|
|
|
}
|
|
|
|
|
|
|
|
size_t SSU2Session::CreateRelayResponseBlock (uint8_t * buf, size_t len,
|
|
|
|
SSU2RelayResponseCode code, uint32_t nonce, uint64_t token, bool v4)
|
|
|
|
{
|
|
|
|
buf[0] = eSSU2BlkRelayResponse;
|
|
|
|
buf[3] = 0; // flag
|
|
|
|
buf[4] = code; // code
|
|
|
|
htobe32buf (buf + 5, nonce); // nonce
|
|
|
|
htobe32buf (buf + 9, i2p::util::GetSecondsSinceEpoch ()); // timestamp
|
|
|
|
buf[13] = 2; // ver
|
|
|
|
size_t csz = 0;
|
|
|
|
if (code == eSSU2RelayResponseCodeAccept)
|
|
|
|
{
|
|
|
|
auto addr = i2p::context.GetRouterInfo ().GetSSU2Address (v4);
|
|
|
|
if (!addr)
|
|
|
|
{
|
|
|
|
LogPrint (eLogError, "SSU2: Can't find local address for RelayResponse");
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
csz = CreateEndpoint (buf + 15, len - 15, boost::asio::ip::udp::endpoint (addr->host, addr->port));
|
|
|
|
if (!csz)
|
|
|
|
{
|
|
|
|
LogPrint (eLogError, "SSU2: Can't create local endpoint for RelayResponse");
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
buf[14] = csz; // csz
|
|
|
|
// signature
|
|
|
|
size_t signatureLen = i2p::context.GetIdentity ()->GetSignatureLen ();
|
|
|
|
if (15 + csz + signatureLen > len)
|
|
|
|
{
|
|
|
|
LogPrint (eLogError, "SSU2: Buffer for RelayResponse signature is too small ", len);
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
SignedData s;
|
|
|
|
s.Insert ((const uint8_t *)"RelayAgreementOK", 16); // prologue
|
|
|
|
if (code == eSSU2RelayResponseCodeAccept || code >= 64) // Charlie
|
|
|
|
s.Insert (GetRemoteIdentity ()->GetIdentHash (), 32); // bhash
|
|
|
|
else // Bob's reject
|
|
|
|
s.Insert (i2p::context.GetIdentity ()->GetIdentHash (), 32); // bhash
|
|
|
|
s.Insert (buf + 5, 10 + csz); // nonce, timestamp, ver, csz and Charlie's endpoint
|
|
|
|
s.Sign (i2p::context.GetPrivateKeys (), buf + 15 + csz);
|
|
|
|
size_t payloadSize = 12 + csz + signatureLen;
|
|
|
|
if (!code)
|
|
|
|
{
|
|
|
|
if (payloadSize + 11 > len)
|
|
|
|
{
|
|
|
|
LogPrint (eLogError, "SSU2: Buffer for RelayResponse token is too small ", len);
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
memcpy (buf + 3 + payloadSize, &token, 8);
|
|
|
|
payloadSize += 8;
|
|
|
|
}
|
|
|
|
htobe16buf (buf + 1, payloadSize); // size
|
|
|
|
return payloadSize + 3;
|
|
|
|
}
|
|
|
|
|
|
|
|
size_t SSU2Session::CreatePeerTestBlock (uint8_t * buf, size_t len, uint8_t msg, SSU2PeerTestCode code,
|
|
|
|
const uint8_t * routerHash, const uint8_t * signedData, size_t signedDataLen)
|
|
|
|
{
|
|
|
|
buf[0] = eSSU2BlkPeerTest;
|
|
|
|
size_t payloadSize = 3/* msg, code, flag */ + signedDataLen;
|
|
|
|
if (routerHash) payloadSize += 32; // router hash
|
|
|
|
if (payloadSize + 3 > len) return 0;
|
|
|
|
htobe16buf (buf + 1, payloadSize); // size
|
|
|
|
buf[3] = msg; // msg
|
|
|
|
buf[4] = (uint8_t)code; // code
|
|
|
|
buf[5] = 0; //flag
|
|
|
|
size_t offset = 6;
|
|
|
|
if (routerHash)
|
|
|
|
{
|
|
|
|
memcpy (buf + offset, routerHash, 32); // router hash
|
|
|
|
offset += 32;
|
|
|
|
}
|
|
|
|
memcpy (buf + offset, signedData, signedDataLen);
|
|
|
|
return payloadSize + 3;
|
|
|
|
}
|
|
|
|
|
|
|
|
size_t SSU2Session::CreatePeerTestBlock (uint8_t * buf, size_t len, uint32_t nonce)
|
|
|
|
{
|
|
|
|
auto localAddress = FindLocalAddress ();
|
|
|
|
if (!localAddress || !localAddress->port || localAddress->host.is_unspecified () ||
|
|
|
|
localAddress->host.is_v4 () != m_RemoteEndpoint.address ().is_v4 ())
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Can't find local address for peer test");
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
// signed data
|
|
|
|
auto ts = i2p::util::GetSecondsSinceEpoch ();
|
|
|
|
uint8_t signedData[96];
|
|
|
|
signedData[0] = 2; // ver
|
|
|
|
htobe32buf (signedData + 1, nonce);
|
|
|
|
htobe32buf (signedData + 5, ts);
|
|
|
|
size_t asz = CreateEndpoint (signedData + 10, 86, boost::asio::ip::udp::endpoint (localAddress->host, localAddress->port));
|
|
|
|
signedData[9] = asz;
|
|
|
|
// signature
|
|
|
|
SignedData s;
|
|
|
|
s.Insert ((const uint8_t *)"PeerTestValidate", 16); // prologue
|
|
|
|
s.Insert (GetRemoteIdentity ()->GetIdentHash (), 32); // bhash
|
|
|
|
s.Insert (signedData, 10 + asz); // ver, nonce, ts, asz, Alice's endpoint
|
|
|
|
s.Sign (i2p::context.GetPrivateKeys (), signedData + 10 + asz);
|
|
|
|
return CreatePeerTestBlock (buf, len, 1, eSSU2PeerTestCodeAccept, nullptr,
|
|
|
|
signedData, 10 + asz + i2p::context.GetIdentity ()->GetSignatureLen ());
|
|
|
|
}
|
|
|
|
|
|
|
|
size_t SSU2Session::CreateTerminationBlock (uint8_t * buf, size_t len)
|
|
|
|
{
|
|
|
|
buf[0] = eSSU2BlkTermination;
|
|
|
|
htobe16buf (buf + 1, 9);
|
|
|
|
htobe64buf (buf + 3, m_ReceivePacketNum);
|
|
|
|
buf[11] = (uint8_t)m_TerminationReason;
|
|
|
|
return 12;
|
|
|
|
}
|
|
|
|
|
|
|
|
std::shared_ptr<const i2p::data::RouterInfo> SSU2Session::ExtractRouterInfo (const uint8_t * buf, size_t size)
|
|
|
|
{
|
|
|
|
if (size < 2) return nullptr;
|
|
|
|
// TODO: handle frag
|
|
|
|
std::shared_ptr<const i2p::data::RouterInfo> ri;
|
|
|
|
if (buf[0] & SSU2_ROUTER_INFO_FLAG_GZIP)
|
|
|
|
{
|
|
|
|
i2p::data::GzipInflator inflator;
|
|
|
|
uint8_t uncompressed[i2p::data::MAX_RI_BUFFER_SIZE];
|
|
|
|
size_t uncompressedSize = inflator.Inflate (buf + 2, size - 2, uncompressed, i2p::data::MAX_RI_BUFFER_SIZE);
|
|
|
|
if (uncompressedSize && uncompressedSize <= i2p::data::MAX_RI_BUFFER_SIZE)
|
|
|
|
ri = std::make_shared<i2p::data::RouterInfo>(uncompressed, uncompressedSize);
|
|
|
|
else
|
|
|
|
LogPrint (eLogInfo, "SSU2: RouterInfo decompression failed ", uncompressedSize);
|
|
|
|
}
|
|
|
|
else if (size <= i2p::data::MAX_RI_BUFFER_SIZE + 2)
|
|
|
|
ri = std::make_shared<i2p::data::RouterInfo>(buf + 2, size - 2);
|
|
|
|
else
|
|
|
|
LogPrint (eLogInfo, "SSU2: RouterInfo is too long ", size);
|
|
|
|
return ri;
|
|
|
|
}
|
|
|
|
|
|
|
|
bool SSU2Session::UpdateReceivePacketNum (uint32_t packetNum)
|
|
|
|
{
|
|
|
|
if (packetNum <= m_ReceivePacketNum) return false; // duplicate
|
|
|
|
if (packetNum == m_ReceivePacketNum + 1)
|
|
|
|
{
|
|
|
|
if (!m_OutOfSequencePackets.empty ())
|
|
|
|
{
|
|
|
|
auto it = m_OutOfSequencePackets.begin ();
|
|
|
|
if (*it == packetNum + 1)
|
|
|
|
{
|
|
|
|
// first out of sequence packet is in sequence now
|
|
|
|
packetNum++; it++;
|
|
|
|
while (it != m_OutOfSequencePackets.end ())
|
|
|
|
{
|
|
|
|
if (*it == packetNum + 1)
|
|
|
|
{
|
|
|
|
packetNum++;
|
|
|
|
it++;
|
|
|
|
}
|
|
|
|
else // next out of sequence
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
m_OutOfSequencePackets.erase (m_OutOfSequencePackets.begin (), it);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
m_ReceivePacketNum = packetNum;
|
|
|
|
}
|
|
|
|
else
|
|
|
|
m_OutOfSequencePackets.insert (packetNum);
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::SendQuickAck ()
|
|
|
|
{
|
|
|
|
uint8_t payload[SSU2_MAX_PACKET_SIZE];
|
|
|
|
size_t payloadSize = 0;
|
|
|
|
if (m_SendPacketNum > m_LastDatetimeSentPacketNum + SSU2_SEND_DATETIME_NUM_PACKETS)
|
|
|
|
{
|
|
|
|
payload[0] = eSSU2BlkDateTime;
|
|
|
|
htobe16buf (payload + 1, 4);
|
|
|
|
htobe32buf (payload + 3, (i2p::util::GetMillisecondsSinceEpoch () + 500)/1000);
|
|
|
|
payloadSize += 7;
|
|
|
|
m_LastDatetimeSentPacketNum = m_SendPacketNum;
|
|
|
|
}
|
|
|
|
payloadSize += CreateAckBlock (payload + payloadSize, m_MaxPayloadSize - payloadSize);
|
|
|
|
payloadSize += CreatePaddingBlock (payload + payloadSize, m_MaxPayloadSize - payloadSize);
|
|
|
|
SendData (payload, payloadSize);
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::SendTermination ()
|
|
|
|
{
|
|
|
|
uint8_t payload[32];
|
|
|
|
size_t payloadSize = CreateTerminationBlock (payload, 32);
|
|
|
|
payloadSize += CreatePaddingBlock (payload + payloadSize, 32 - payloadSize);
|
|
|
|
SendData (payload, payloadSize);
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::SendPathResponse (const uint8_t * data, size_t len)
|
|
|
|
{
|
|
|
|
if (len > m_MaxPayloadSize - 3)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Incorrect data size for path response ", len);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
uint8_t payload[SSU2_MAX_PACKET_SIZE];
|
|
|
|
payload[0] = eSSU2BlkPathResponse;
|
|
|
|
htobe16buf (payload + 1, len);
|
|
|
|
memcpy (payload + 3, data, len);
|
|
|
|
size_t payloadSize = len + 3;
|
|
|
|
if (payloadSize < m_MaxPayloadSize)
|
|
|
|
payloadSize += CreatePaddingBlock (payload + payloadSize, m_MaxPayloadSize - payloadSize, payloadSize < 8 ? 8 : 0);
|
|
|
|
SendData (payload, payloadSize);
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::SendPathChallenge ()
|
|
|
|
{
|
|
|
|
uint8_t payload[SSU2_MAX_PACKET_SIZE];
|
|
|
|
payload[0] = eSSU2BlkPathChallenge;
|
|
|
|
size_t len = m_Server.GetRng ()() % (m_MaxPayloadSize - 3);
|
|
|
|
htobe16buf (payload + 1, len);
|
|
|
|
if (len > 0)
|
|
|
|
{
|
|
|
|
RAND_bytes (payload + 3, len);
|
|
|
|
i2p::data::IdentHash * hash = new i2p::data::IdentHash ();
|
|
|
|
SHA256 (payload + 3, len, *hash);
|
|
|
|
m_PathChallenge.reset (hash);
|
|
|
|
}
|
|
|
|
len += 3;
|
|
|
|
if (len < m_MaxPayloadSize)
|
|
|
|
len += CreatePaddingBlock (payload + len, m_MaxPayloadSize - len, len < 8 ? 8 : 0);
|
|
|
|
SendData (payload, len);
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::CleanUp (uint64_t ts)
|
|
|
|
{
|
|
|
|
for (auto it = m_IncompleteMessages.begin (); it != m_IncompleteMessages.end ();)
|
|
|
|
{
|
|
|
|
if (ts > it->second->lastFragmentInsertTime + SSU2_INCOMPLETE_MESSAGES_CLEANUP_TIMEOUT)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: message ", it->first, " was not completed in ", SSU2_INCOMPLETE_MESSAGES_CLEANUP_TIMEOUT, " seconds, deleted");
|
|
|
|
it = m_IncompleteMessages.erase (it);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
++it;
|
|
|
|
}
|
|
|
|
if (m_ReceivedI2NPMsgIDs.size () > SSU2_MAX_NUM_RECEIVED_I2NP_MSGIDS || ts > GetLastActivityTimestamp () + SSU2_DECAY_INTERVAL)
|
|
|
|
// decay
|
|
|
|
m_ReceivedI2NPMsgIDs.clear ();
|
|
|
|
else
|
|
|
|
{
|
|
|
|
// delete old received msgIDs
|
|
|
|
for (auto it = m_ReceivedI2NPMsgIDs.begin (); it != m_ReceivedI2NPMsgIDs.end ();)
|
|
|
|
{
|
|
|
|
if (ts > it->second + SSU2_RECEIVED_I2NP_MSGIDS_CLEANUP_TIMEOUT)
|
|
|
|
it = m_ReceivedI2NPMsgIDs.erase (it);
|
|
|
|
else
|
|
|
|
++it;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
if (!m_OutOfSequencePackets.empty ())
|
|
|
|
{
|
|
|
|
int ranges = 0;
|
|
|
|
while (ranges < 8 && !m_OutOfSequencePackets.empty () &&
|
|
|
|
(m_OutOfSequencePackets.size () > 2*SSU2_MAX_NUM_ACK_RANGES ||
|
|
|
|
*m_OutOfSequencePackets.rbegin () > m_ReceivePacketNum + SSU2_MAX_NUM_ACK_PACKETS))
|
|
|
|
{
|
|
|
|
uint32_t packet = *m_OutOfSequencePackets.begin ();
|
|
|
|
if (packet > m_ReceivePacketNum + 1)
|
|
|
|
{
|
|
|
|
// like we've just received all packets before first
|
|
|
|
packet--;
|
|
|
|
m_ReceivePacketNum = packet - 1;
|
|
|
|
UpdateReceivePacketNum (packet);
|
|
|
|
ranges++;
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
LogPrint (eLogError, "SSU2: Out of sequence packet ", packet, " is less than last received ", m_ReceivePacketNum);
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
if (m_OutOfSequencePackets.size () > 255*4)
|
|
|
|
{
|
|
|
|
// seems we have a serious network issue
|
|
|
|
m_ReceivePacketNum = *m_OutOfSequencePackets.rbegin ();
|
|
|
|
m_OutOfSequencePackets.clear ();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
for (auto it = m_RelaySessions.begin (); it != m_RelaySessions.end ();)
|
|
|
|
{
|
|
|
|
if (ts > it->second.second + SSU2_RELAY_NONCE_EXPIRATION_TIMEOUT)
|
|
|
|
{
|
|
|
|
LogPrint (eLogWarning, "SSU2: Relay nonce ", it->first, " was not responded in ", SSU2_RELAY_NONCE_EXPIRATION_TIMEOUT, " seconds, deleted");
|
|
|
|
it = m_RelaySessions.erase (it);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
++it;
|
|
|
|
}
|
|
|
|
if (m_PathChallenge)
|
|
|
|
RequestTermination (eSSU2TerminationReasonNormalClose);
|
|
|
|
}
|
|
|
|
|
|
|
|
void SSU2Session::FlushData ()
|
|
|
|
{
|
|
|
|
bool sent = SendQueue (); // if we have something to send
|
|
|
|
if (sent)
|
|
|
|
SetSendQueueSize (m_SendQueue.size ());
|
|
|
|
if (m_IsDataReceived)
|
|
|
|
{
|
|
|
|
if (!sent) SendQuickAck ();
|
|
|
|
m_Handler.Flush ();
|
|
|
|
m_IsDataReceived = false;
|
|
|
|
}
|
|
|
|
else if (!sent && !m_SentPackets.empty ()) // if only acks received, nothing sent and we still have something to resend
|
|
|
|
Resend (i2p::util::GetMillisecondsSinceEpoch ()); // than right time to resend
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|