mirror of
https://github.com/PurpleI2P/i2pd
synced 2024-11-10 08:00:38 +03:00
578 lines
16 KiB
C++
578 lines
16 KiB
C++
#include <fstream>
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#include <algorithm>
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#include <cryptopp/dh.h>
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#include <cryptopp/gzip.h>
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#include "Log.h"
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#include "RouterInfo.h"
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#include "RouterContext.h"
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#include "Tunnel.h"
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#include "Timestamp.h"
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#include "CryptoConst.h"
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#include "Garlic.h"
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#include "Streaming.h"
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namespace i2p
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{
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namespace stream
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{
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Stream::Stream (boost::asio::io_service& service, StreamingDestination * local,
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const i2p::data::LeaseSet& remote): m_Service (service), m_SendStreamID (0),
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m_SequenceNumber (0), m_LastReceivedSequenceNumber (0), m_IsOpen (false),
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m_LeaseSetUpdated (true), m_LocalDestination (local), m_RemoteLeaseSet (remote),
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m_OutboundTunnel (nullptr), m_ReceiveTimer (m_Service)
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{
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m_RecvStreamID = i2p::context.GetRandomNumberGenerator ().GenerateWord32 ();
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UpdateCurrentRemoteLease ();
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}
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Stream::~Stream ()
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{
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m_ReceiveTimer.cancel ();
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while (!m_ReceiveQueue.empty ())
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{
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auto packet = m_ReceiveQueue.front ();
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m_ReceiveQueue.pop ();
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delete packet;
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}
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for (auto it: m_SavedPackets)
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delete it;
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}
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void Stream::HandleNextPacket (Packet * packet)
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{
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if (!m_SendStreamID)
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m_SendStreamID = packet->GetReceiveStreamID ();
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uint32_t receivedSeqn = packet->GetSeqn ();
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LogPrint ("Received seqn=", receivedSeqn);
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if (!receivedSeqn || receivedSeqn == m_LastReceivedSequenceNumber + 1)
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{
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// we have received next in sequence message
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ProcessPacket (packet);
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// we should also try stored messages if any
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for (auto it = m_SavedPackets.begin (); it != m_SavedPackets.end ();)
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{
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if ((*it)->GetSeqn () == m_LastReceivedSequenceNumber + 1)
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{
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Packet * savedPacket = *it;
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m_SavedPackets.erase (it++);
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ProcessPacket (savedPacket);
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}
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else
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break;
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}
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// send ack for last message
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if (m_IsOpen)
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SendQuickAck ();
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}
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else
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{
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if (receivedSeqn <= m_LastReceivedSequenceNumber)
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{
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// we have received duplicate. Most likely our outbound tunnel is dead
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LogPrint ("Duplicate message ", receivedSeqn, " received");
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UpdateCurrentRemoteLease (); // pick another lease
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m_OutboundTunnel = i2p::tunnel::tunnels.GetNextOutboundTunnel (); // pick another tunnel
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if (m_OutboundTunnel)
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SendQuickAck (); // resend ack for previous message again
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delete packet; // packet dropped
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}
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else
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{
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LogPrint ("Missing messages from ", m_LastReceivedSequenceNumber + 1, " to ", receivedSeqn - 1);
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// save message and wait for missing message again
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SavePacket (packet);
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}
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}
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}
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void Stream::SavePacket (Packet * packet)
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{
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m_SavedPackets.insert (packet);
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}
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void Stream::ProcessPacket (Packet * packet)
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{
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// process flags
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uint32_t receivedSeqn = packet->GetSeqn ();
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uint16_t flags = packet->GetFlags ();
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LogPrint ("Process seqn=", receivedSeqn, ", flags=", flags);
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const uint8_t * optionData = packet->GetOptionData ();
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if (flags & PACKET_FLAG_SYNCHRONIZE)
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{
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LogPrint ("Synchronize");
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}
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if (flags & PACKET_FLAG_SIGNATURE_INCLUDED)
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{
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LogPrint ("Signature");
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optionData += 40;
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}
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if (flags & PACKET_FLAG_FROM_INCLUDED)
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{
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LogPrint ("From identity");
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optionData += sizeof (i2p::data::Identity);
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}
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packet->offset = packet->GetPayload () - packet->buf;
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if (packet->GetLength () > 0)
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{
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m_ReceiveQueue.push (packet);
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m_ReceiveTimer.cancel ();
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}
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else
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delete packet;
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m_LastReceivedSequenceNumber = receivedSeqn;
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if (flags & PACKET_FLAG_CLOSE)
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{
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LogPrint ("Closed");
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SendQuickAck (); // send ack for close explicitly?
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m_IsOpen = false;
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}
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}
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size_t Stream::Send (uint8_t * buf, size_t len, int timeout)
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{
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if (!m_IsOpen)
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ConnectAndSend (buf, len);
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else
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{
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// TODO: implement
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}
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return len;
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}
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void Stream::ConnectAndSend (uint8_t * buf, size_t len)
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{
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m_IsOpen = true;
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Packet * p = new Packet ();
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uint8_t * packet = p->GetBuffer ();
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// TODO: implement setters
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size_t size = 0;
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*(uint32_t *)(packet + size) = htobe32 (m_SendStreamID);
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size += 4; // sendStreamID
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*(uint32_t *)(packet + size) = htobe32 (m_RecvStreamID);
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size += 4; // receiveStreamID
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*(uint32_t *)(packet + size) = htobe32 (m_SequenceNumber);
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size += 4; // sequenceNum
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*(uint32_t *)(packet + size) = 0; // TODO
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size += 4; // ack Through
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packet[size] = 0;
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size++; // NACK count
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size++; // resend delay
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// TODO: for initial packet only, following packets have different falgs
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*(uint16_t *)(packet + size) = htobe16 (PACKET_FLAG_SYNCHRONIZE |
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PACKET_FLAG_FROM_INCLUDED | PACKET_FLAG_SIGNATURE_INCLUDED |
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PACKET_FLAG_MAX_PACKET_SIZE_INCLUDED | PACKET_FLAG_NO_ACK);
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size += 2; // flags
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*(uint16_t *)(packet + size) = htobe16 (sizeof (i2p::data::Identity) + 40 + 2); // identity + signature + packet size
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size += 2; // options size
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memcpy (packet + size, &m_LocalDestination->GetIdentity (), sizeof (i2p::data::Identity));
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size += sizeof (i2p::data::Identity); // from
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*(uint16_t *)(packet + size) = htobe16 (STREAMING_MTU);
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size += 2; // max packet size
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uint8_t * signature = packet + size; // set it later
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memset (signature, 0, 40); // zeroes for now
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size += 40; // signature
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memcpy (packet + size, buf, len);
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size += len; // payload
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m_LocalDestination->Sign (packet, size, signature);
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p->len = size;
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m_Service.post (boost::bind (&Stream::SendPacket, this, p));
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}
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void Stream::SendQuickAck ()
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{
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uint8_t packet[MAX_PACKET_SIZE];
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size_t size = 0;
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*(uint32_t *)(packet + size) = htobe32 (m_SendStreamID);
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size += 4; // sendStreamID
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*(uint32_t *)(packet + size) = htobe32 (m_RecvStreamID);
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size += 4; // receiveStreamID
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*(uint32_t *)(packet + size) = 0; // this is plain Ack message
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size += 4; // sequenceNum
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*(uint32_t *)(packet + size) = htobe32 (m_LastReceivedSequenceNumber);
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size += 4; // ack Through
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packet[size] = 0;
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size++; // NACK count
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size++; // resend delay
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*(uint16_t *)(packet + size) = 0; // nof flags set
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size += 2; // flags
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*(uint16_t *)(packet + size) = 0; // no options
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size += 2; // options size
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if (SendPacket (packet, size))
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LogPrint ("Quick Ack sent");
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}
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void Stream::Close ()
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{
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if (m_IsOpen)
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{
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m_IsOpen = false;
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uint8_t packet[MAX_PACKET_SIZE];
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size_t size = 0;
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*(uint32_t *)(packet + size) = htobe32 (m_SendStreamID);
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size += 4; // sendStreamID
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*(uint32_t *)(packet + size) = htobe32 (m_RecvStreamID);
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size += 4; // receiveStreamID
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*(uint32_t *)(packet + size) = htobe32 (m_SequenceNumber);
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size += 4; // sequenceNum
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*(uint32_t *)(packet + size) = htobe32 (m_LastReceivedSequenceNumber);
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size += 4; // ack Through
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packet[size] = 0;
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size++; // NACK count
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size++; // resend delay
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*(uint16_t *)(packet + size) = PACKET_FLAG_CLOSE | PACKET_FLAG_SIGNATURE_INCLUDED;
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size += 2; // flags
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*(uint16_t *)(packet + size) = htobe16 (40); // 40 bytes signature
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size += 2; // options size
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uint8_t * signature = packet + size;
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memset (packet + size, 0, 40);
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size += 40; // signature
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m_LocalDestination->Sign (packet, size, signature);
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if (SendPacket (packet, size))
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LogPrint ("FIN sent");
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}
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}
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size_t Stream::ConcatenatePackets (uint8_t * buf, size_t len)
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{
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size_t pos = 0;
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while (pos < len && !m_ReceiveQueue.empty ())
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{
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Packet * packet = m_ReceiveQueue.front ();
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size_t l = std::min (packet->GetLength (), len - pos);
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memcpy (buf + pos, packet->GetBuffer (), l);
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pos += l;
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packet->offset += l;
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if (!packet->GetLength ())
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{
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m_ReceiveQueue.pop ();
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delete packet;
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}
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}
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return pos;
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}
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bool Stream::SendPacket (Packet * packet)
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{
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if (packet)
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{
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bool ret = SendPacket (packet->GetBuffer (), packet->GetLength ());
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delete packet;
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return ret;
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}
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else
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return false;
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}
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bool Stream::SendPacket (const uint8_t * buf, size_t len)
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{
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const I2NPMessage * leaseSet = nullptr;
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if (m_LeaseSetUpdated)
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{
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leaseSet = m_LocalDestination->GetLeaseSet ();
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m_LeaseSetUpdated = false;
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}
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I2NPMessage * msg = i2p::garlic::routing.WrapMessage (m_RemoteLeaseSet,
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CreateDataMessage (this, buf, len), leaseSet);
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if (!m_OutboundTunnel)
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m_OutboundTunnel = m_LocalDestination->GetTunnelPool ()->GetNextOutboundTunnel ();
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if (m_OutboundTunnel)
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{
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auto ts = i2p::util::GetMillisecondsSinceEpoch ();
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if (ts >= m_CurrentRemoteLease.endDate)
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UpdateCurrentRemoteLease ();
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if (ts < m_CurrentRemoteLease.endDate)
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{
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m_OutboundTunnel->SendTunnelDataMsg (m_CurrentRemoteLease.tunnelGateway, m_CurrentRemoteLease.tunnelID, msg);
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return true;
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}
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else
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{
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LogPrint ("All leases are expired");
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DeleteI2NPMessage (msg);
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}
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}
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else
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{
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LogPrint ("No outbound tunnels in the pool");
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DeleteI2NPMessage (msg);
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}
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return false;
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}
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void Stream::UpdateCurrentRemoteLease ()
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{
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auto leases = m_RemoteLeaseSet.GetNonExpiredLeases ();
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if (!leases.empty ())
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{
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uint32_t i = i2p::context.GetRandomNumberGenerator ().GenerateWord32 (0, leases.size () - 1);
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m_CurrentRemoteLease = leases[i];
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}
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else
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m_CurrentRemoteLease.endDate = 0;
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}
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StreamingDestination::StreamingDestination (): m_LeaseSet (nullptr)
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{
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m_Keys = i2p::data::CreateRandomKeys ();
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m_IdentHash = m_Keys.pub.Hash ();
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m_SigningPrivateKey.Initialize (i2p::crypto::dsap, i2p::crypto::dsaq, i2p::crypto::dsag,
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CryptoPP::Integer (m_Keys.signingPrivateKey, 20));
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CryptoPP::DH dh (i2p::crypto::elgp, i2p::crypto::elgg);
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dh.GenerateKeyPair(i2p::context.GetRandomNumberGenerator (), m_EncryptionPrivateKey, m_EncryptionPublicKey);
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m_Pool = i2p::tunnel::tunnels.CreateTunnelPool (*this);
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}
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StreamingDestination::StreamingDestination (const std::string& fullPath): m_LeaseSet (nullptr)
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{
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std::ifstream s(fullPath.c_str (), std::ifstream::binary);
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if (s.is_open ())
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s.read ((char *)&m_Keys, sizeof (m_Keys));
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else
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LogPrint ("Can't open file ", fullPath);
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CryptoPP::DH dh (i2p::crypto::elgp, i2p::crypto::elgg);
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dh.GenerateKeyPair(i2p::context.GetRandomNumberGenerator (), m_EncryptionPrivateKey, m_EncryptionPublicKey);
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m_Pool = i2p::tunnel::tunnels.CreateTunnelPool (*this);
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}
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StreamingDestination::~StreamingDestination ()
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{
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if (m_LeaseSet)
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DeleteI2NPMessage (m_LeaseSet);
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if (m_Pool)
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i2p::tunnel::tunnels.DeleteTunnelPool (m_Pool);
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}
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void StreamingDestination::HandleNextPacket (Packet * packet)
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{
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uint32_t sendStreamID = packet->GetSendStreamID ();
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auto it = m_Streams.find (sendStreamID);
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if (it != m_Streams.end ())
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it->second->HandleNextPacket (packet);
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else
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{
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LogPrint ("Unknown stream ", sendStreamID);
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delete packet;
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}
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}
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Stream * StreamingDestination::CreateNewStream (boost::asio::io_service& service,
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const i2p::data::LeaseSet& remote)
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{
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Stream * s = new Stream (service, this, remote);
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m_Streams[s->GetRecvStreamID ()] = s;
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return s;
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}
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void StreamingDestination::DeleteStream (Stream * stream)
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{
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if (stream)
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{
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m_Streams.erase (stream->GetRecvStreamID ());
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delete stream;
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}
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}
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void StreamingDestination::UpdateLeaseSet ()
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{
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auto newLeaseSet = CreateLeaseSet ();
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// TODO: make it atomic
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auto oldLeaseSet = m_LeaseSet;
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m_LeaseSet = newLeaseSet;
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if (oldLeaseSet)
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DeleteI2NPMessage (oldLeaseSet);
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for (auto it: m_Streams)
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it.second->SetLeaseSetUpdated ();
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}
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const I2NPMessage * StreamingDestination::GetLeaseSet ()
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{
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if (!m_LeaseSet)
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m_LeaseSet = CreateLeaseSet ();
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else
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RenewI2NPMessageHeader (m_LeaseSet);
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return m_LeaseSet;
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}
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I2NPMessage * StreamingDestination::CreateLeaseSet () const
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{
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I2NPMessage * m = NewI2NPMessage ();
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I2NPDatabaseStoreMsg * msg = (I2NPDatabaseStoreMsg *)m->GetPayload ();
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memcpy (msg->key, (const uint8_t *)m_IdentHash, 32);
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msg->type = 1; // LeaseSet
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msg->replyToken = 0;
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uint8_t * buf = m->GetPayload () + sizeof (I2NPDatabaseStoreMsg);
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size_t size = 0;
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memcpy (buf + size, &m_Keys.pub, sizeof (m_Keys.pub));
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size += sizeof (m_Keys.pub); // destination
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memcpy (buf + size, m_Pool->GetEncryptionPublicKey (), 256);
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size += 256; // encryption key
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memset (buf + size, 0, 128);
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size += 128; // signing key
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auto tunnels = m_Pool->GetInboundTunnels (5); // 5 tunnels maximum
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buf[size] = tunnels.size (); // num leases
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size++; // num
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for (auto it: tunnels)
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{
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auto tunnel = it;
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memcpy (buf + size, (const uint8_t *)tunnel->GetNextIdentHash (), 32);
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size += 32; // tunnel_gw
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*(uint32_t *)(buf + size) = htobe32 (tunnel->GetNextTunnelID ());
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size += 4; // tunnel_id
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uint64_t ts = tunnel->GetCreationTime () + i2p::tunnel::TUNNEL_EXPIRATION_TIMEOUT - 60; // 1 minute before expiration
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ts *= 1000; // in milliseconds
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*(uint64_t *)(buf + size) = htobe64 (ts);
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size += 8; // end_date
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}
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Sign (buf, size, buf+ size);
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size += 40; // signature
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LogPrint ("Local LeaseSet of ", tunnels.size (), " leases created");
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m->len += size + sizeof (I2NPDatabaseStoreMsg);
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FillI2NPMessageHeader (m, eI2NPDatabaseStore);
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return m;
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}
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void StreamingDestination::Sign (uint8_t * buf, int len, uint8_t * signature) const
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{
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CryptoPP::DSA::Signer signer (m_SigningPrivateKey);
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signer.SignMessage (i2p::context.GetRandomNumberGenerator (), buf, len, signature);
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}
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StreamingDestinations destinations;
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void StreamingDestinations::Start ()
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{
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if (!m_SharedLocalDestination)
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m_SharedLocalDestination = new StreamingDestination ();
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m_IsRunning = true;
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m_Thread = new std::thread (std::bind (&StreamingDestinations::Run, this));
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}
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void StreamingDestinations::Stop ()
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{
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delete m_SharedLocalDestination;
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m_IsRunning = false;
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m_Service.stop ();
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if (m_Thread)
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{
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m_Thread->join ();
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delete m_Thread;
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m_Thread = 0;
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}
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}
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void StreamingDestinations::Run ()
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{
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m_Service.run ();
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}
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Stream * StreamingDestinations::CreateClientStream (const i2p::data::LeaseSet& remote)
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{
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if (!m_SharedLocalDestination) return nullptr;
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return m_SharedLocalDestination->CreateNewStream (m_Service, remote);
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}
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void StreamingDestinations::DeleteClientStream (Stream * stream)
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{
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if (m_SharedLocalDestination)
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m_SharedLocalDestination->DeleteStream (stream);
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else
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delete stream;
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}
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void StreamingDestinations::HandleNextPacket (i2p::data::IdentHash destination, Packet * packet)
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{
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m_Service.post (boost::bind (&StreamingDestinations::PostNextPacket, this, destination, packet));
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}
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void StreamingDestinations::PostNextPacket (i2p::data::IdentHash destination, Packet * packet)
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{
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// TODO: we have onle one destination, might be more
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if (m_SharedLocalDestination)
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m_SharedLocalDestination->HandleNextPacket (packet);
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}
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Stream * CreateStream (const i2p::data::LeaseSet& remote)
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{
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return destinations.CreateClientStream (remote);
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}
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void DeleteStream (Stream * stream)
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{
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destinations.DeleteClientStream (stream);
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}
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void StartStreaming ()
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{
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destinations.Start ();
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}
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void StopStreaming ()
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{
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destinations.Stop ();
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}
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void HandleDataMessage (i2p::data::IdentHash destination, const uint8_t * buf, size_t len)
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{
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uint32_t length = be32toh (*(uint32_t *)buf);
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buf += 4;
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// we assume I2CP payload
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if (buf[9] == 6) // streaming protocol
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{
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// unzip it
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CryptoPP::Gunzip decompressor;
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decompressor.Put (buf, length);
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decompressor.MessageEnd();
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Packet * uncompressed = new Packet;
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uncompressed->offset = 0;
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uncompressed->len = decompressor.MaxRetrievable ();
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if (uncompressed->len > MAX_PACKET_SIZE)
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{
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LogPrint ("Recieved packet size exceeds mac packet size");
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uncompressed->len = MAX_PACKET_SIZE;
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}
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decompressor.Get (uncompressed->buf, uncompressed->len);
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// then forward to streaming engine thread
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destinations.HandleNextPacket (destination, uncompressed);
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}
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else
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LogPrint ("Data: protocol ", buf[9], " is not supported");
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}
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I2NPMessage * CreateDataMessage (Stream * s, const uint8_t * payload, size_t len)
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{
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I2NPMessage * msg = NewI2NPMessage ();
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CryptoPP::Gzip compressor;
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compressor.SetDeflateLevel (CryptoPP::Gzip::MIN_DEFLATE_LEVEL);
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compressor.Put (payload, len);
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compressor.MessageEnd();
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int size = compressor.MaxRetrievable ();
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uint8_t * buf = msg->GetPayload ();
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*(uint32_t *)buf = htobe32 (size); // length
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buf += 4;
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compressor.Get (buf, size);
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memset (buf + 4, 0, 4); // source and destination ports. TODO: fill with proper values later
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buf[9] = 6; // streaming protocol
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msg->len += size + 4;
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FillI2NPMessageHeader (msg, eI2NPData);
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return msg;
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}
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}
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}
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