mirror of
https://github.com/PurpleI2P/i2pd.git
synced 2024-11-02 09:40:18 +00:00
1225 lines
37 KiB
C++
1225 lines
37 KiB
C++
#include <string.h>
|
|
#include <boost/bind.hpp>
|
|
#include <cryptopp/dh.h>
|
|
#include <cryptopp/sha.h>
|
|
#include "CryptoConst.h"
|
|
#include "Log.h"
|
|
#include "Timestamp.h"
|
|
#include "RouterContext.h"
|
|
#include "Transports.h"
|
|
#include "hmac.h"
|
|
#include "SSU.h"
|
|
|
|
namespace i2p
|
|
{
|
|
namespace ssu
|
|
{
|
|
|
|
SSUSession::SSUSession (SSUServer& server, boost::asio::ip::udp::endpoint& remoteEndpoint,
|
|
const i2p::data::RouterInfo * router, bool peerTest ):
|
|
m_Server (server), m_RemoteEndpoint (remoteEndpoint), m_RemoteRouter (router),
|
|
m_Timer (m_Server.GetService ()), m_DHKeysPair (nullptr), m_PeerTest (peerTest),
|
|
m_State (eSessionStateUnknown), m_IsSessionKey (false), m_RelayTag (0),
|
|
m_Data (*this), m_NumSentBytes (0), m_NumReceivedBytes (0)
|
|
{
|
|
m_CreationTime = i2p::util::GetSecondsSinceEpoch ();
|
|
if (!router) // incoming session
|
|
ScheduleConnectTimer ();
|
|
}
|
|
|
|
SSUSession::~SSUSession ()
|
|
{
|
|
delete m_DHKeysPair;
|
|
}
|
|
|
|
void SSUSession::CreateAESandMacKey (const uint8_t * pubKey)
|
|
{
|
|
CryptoPP::DH dh (i2p::crypto::elgp, i2p::crypto::elgg);
|
|
uint8_t sharedKey[256];
|
|
if (!dh.Agree (sharedKey, m_DHKeysPair->privateKey, pubKey))
|
|
{
|
|
LogPrint ("Couldn't create shared key");
|
|
return;
|
|
};
|
|
|
|
if (sharedKey[0] & 0x80)
|
|
{
|
|
m_SessionKey[0] = 0;
|
|
memcpy (m_SessionKey + 1, sharedKey, 31);
|
|
memcpy (m_MacKey, sharedKey + 31, 32);
|
|
}
|
|
else if (sharedKey[0])
|
|
{
|
|
memcpy (m_SessionKey, sharedKey, 32);
|
|
memcpy (m_MacKey, sharedKey + 32, 32);
|
|
}
|
|
else
|
|
{
|
|
// find first non-zero byte
|
|
uint8_t * nonZero = sharedKey + 1;
|
|
while (!*nonZero)
|
|
{
|
|
nonZero++;
|
|
if (nonZero - sharedKey > 32)
|
|
{
|
|
LogPrint ("First 32 bytes of shared key is all zeros. Ignored");
|
|
return;
|
|
}
|
|
}
|
|
|
|
memcpy (m_SessionKey, nonZero, 32);
|
|
CryptoPP::SHA256().CalculateDigest(m_MacKey, nonZero, 64 - (nonZero - sharedKey));
|
|
}
|
|
m_IsSessionKey = true;
|
|
m_SessionKeyEncryption.SetKey (m_SessionKey);
|
|
m_SessionKeyDecryption.SetKey (m_SessionKey);
|
|
}
|
|
|
|
void SSUSession::ProcessNextMessage (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& senderEndpoint)
|
|
{
|
|
m_NumReceivedBytes += len;
|
|
if (m_State == eSessionStateIntroduced)
|
|
{
|
|
// HolePunch received
|
|
LogPrint ("SSU HolePunch of ", len, " bytes received");
|
|
m_State = eSessionStateUnknown;
|
|
Connect ();
|
|
}
|
|
else
|
|
{
|
|
if (!len) return; // ignore zero-length packets
|
|
if (m_State == eSessionStateEstablished)
|
|
ScheduleTermination ();
|
|
|
|
if (m_IsSessionKey && Validate (buf, len, m_MacKey)) // try session key first
|
|
DecryptSessionKey (buf, len);
|
|
else
|
|
{
|
|
// try intro key depending on side
|
|
auto introKey = GetIntroKey ();
|
|
if (introKey && Validate (buf, len, introKey))
|
|
Decrypt (buf, len, introKey);
|
|
else
|
|
{
|
|
// try own intro key
|
|
auto address = i2p::context.GetRouterInfo ().GetSSUAddress ();
|
|
if (!address)
|
|
{
|
|
LogPrint ("SSU is not supported");
|
|
return;
|
|
}
|
|
if (Validate (buf, len, address->key))
|
|
Decrypt (buf, len, address->key);
|
|
else
|
|
{
|
|
LogPrint ("MAC verification failed ", len, " bytes from ", senderEndpoint);
|
|
m_Server.DeleteSession (this);
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
// successfully decrypted
|
|
ProcessMessage (buf, len, senderEndpoint);
|
|
}
|
|
}
|
|
|
|
void SSUSession::ProcessMessage (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& senderEndpoint)
|
|
{
|
|
SSUHeader * header = (SSUHeader *)buf;
|
|
switch (header->GetPayloadType ())
|
|
{
|
|
case PAYLOAD_TYPE_DATA:
|
|
LogPrint ("SSU data received");
|
|
ProcessData (buf + sizeof (SSUHeader), len - sizeof (SSUHeader));
|
|
break;
|
|
case PAYLOAD_TYPE_SESSION_REQUEST:
|
|
ProcessSessionRequest (buf, len, senderEndpoint);
|
|
break;
|
|
case PAYLOAD_TYPE_SESSION_CREATED:
|
|
ProcessSessionCreated (buf, len);
|
|
break;
|
|
case PAYLOAD_TYPE_SESSION_CONFIRMED:
|
|
ProcessSessionConfirmed (buf, len);
|
|
break;
|
|
case PAYLOAD_TYPE_PEER_TEST:
|
|
LogPrint ("SSU peer test received");
|
|
ProcessPeerTest (buf + sizeof (SSUHeader), len - sizeof (SSUHeader), senderEndpoint);
|
|
break;
|
|
case PAYLOAD_TYPE_SESSION_DESTROYED:
|
|
{
|
|
LogPrint ("SSU session destroy received");
|
|
m_Server.DeleteSession (this); // delete this
|
|
break;
|
|
}
|
|
case PAYLOAD_TYPE_RELAY_RESPONSE:
|
|
ProcessRelayResponse (buf, len);
|
|
if (m_State != eSessionStateEstablished)
|
|
m_Server.DeleteSession (this);
|
|
break;
|
|
case PAYLOAD_TYPE_RELAY_REQUEST:
|
|
LogPrint ("SSU relay request received");
|
|
ProcessRelayRequest (buf + sizeof (SSUHeader), len - sizeof (SSUHeader), senderEndpoint);
|
|
break;
|
|
case PAYLOAD_TYPE_RELAY_INTRO:
|
|
LogPrint ("SSU relay intro received");
|
|
ProcessRelayIntro (buf + sizeof (SSUHeader), len - sizeof (SSUHeader));
|
|
break;
|
|
default:
|
|
LogPrint ("Unexpected SSU payload type ", (int)header->GetPayloadType ());
|
|
}
|
|
}
|
|
|
|
void SSUSession::ProcessSessionRequest (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& senderEndpoint)
|
|
{
|
|
LogPrint ("Session request received");
|
|
m_RemoteEndpoint = senderEndpoint;
|
|
if (!m_DHKeysPair)
|
|
m_DHKeysPair = i2p::transports.GetNextDHKeysPair ();
|
|
CreateAESandMacKey (buf + sizeof (SSUHeader));
|
|
SendSessionCreated (buf + sizeof (SSUHeader));
|
|
}
|
|
|
|
void SSUSession::ProcessSessionCreated (uint8_t * buf, size_t len)
|
|
{
|
|
if (!m_RemoteRouter || !m_DHKeysPair)
|
|
{
|
|
LogPrint ("Unsolicited session created message");
|
|
return;
|
|
}
|
|
|
|
LogPrint ("Session created received");
|
|
m_Timer.cancel (); // connect timer
|
|
uint8_t signedData[532]; // x,y, our IP, our port, remote IP, remote port, relayTag, signed on time
|
|
uint8_t * payload = buf + sizeof (SSUHeader);
|
|
uint8_t * y = payload;
|
|
CreateAESandMacKey (y);
|
|
memcpy (signedData, m_DHKeysPair->publicKey, 256); // x
|
|
memcpy (signedData + 256, y, 256); // y
|
|
payload += 256;
|
|
payload += 1; // size, assume 4
|
|
uint8_t * ourAddress = payload;
|
|
boost::asio::ip::address_v4 ourIP (be32toh (*(uint32_t* )ourAddress));
|
|
payload += 4; // address
|
|
uint16_t ourPort = be16toh (*(uint16_t *)payload);
|
|
payload += 2; // port
|
|
memcpy (signedData + 512, ourAddress, 6); // our IP and port
|
|
LogPrint ("Our external address is ", ourIP.to_string (), ":", ourPort);
|
|
i2p::context.UpdateAddress (ourIP.to_string ().c_str ());
|
|
*(uint32_t *)(signedData + 518) = htobe32 (m_RemoteEndpoint.address ().to_v4 ().to_ulong ()); // remote IP
|
|
*(uint16_t *)(signedData + 522) = htobe16 (m_RemoteEndpoint.port ()); // remote port
|
|
memcpy (signedData + 524, payload, 8); // relayTag and signed on time
|
|
m_RelayTag = be32toh (*(uint32_t *)payload);
|
|
payload += 4; // relayTag
|
|
payload += 4; // signed on time
|
|
// decrypt DSA signature
|
|
m_SessionKeyDecryption.SetIV (((SSUHeader *)buf)->iv);
|
|
m_SessionKeyDecryption.Decrypt (payload, 48, payload);
|
|
// verify
|
|
CryptoPP::DSA::PublicKey pubKey;
|
|
pubKey.Initialize (i2p::crypto::dsap, i2p::crypto::dsaq, i2p::crypto::dsag, CryptoPP::Integer (m_RemoteRouter->GetRouterIdentity ().signingKey, 128));
|
|
CryptoPP::DSA::Verifier verifier (pubKey);
|
|
if (!verifier.VerifyMessage (signedData, 532, payload, 40))
|
|
LogPrint ("SSU signature verification failed");
|
|
|
|
SendSessionConfirmed (y, ourAddress);
|
|
}
|
|
|
|
void SSUSession::ProcessSessionConfirmed (uint8_t * buf, size_t len)
|
|
{
|
|
LogPrint ("Session confirmed received");
|
|
uint8_t * payload = buf + sizeof (SSUHeader);
|
|
payload++; // identity fragment info
|
|
uint16_t identitySize = be16toh (*(uint16_t *)payload);
|
|
payload += 2; // size of identity fragment
|
|
if (identitySize == i2p::data::DEFAULT_IDENTITY_SIZE)
|
|
{
|
|
i2p::data::Identity ident;
|
|
ident.FromBuffer (payload, identitySize);
|
|
m_RemoteIdent = ident.Hash ();
|
|
m_Data.UpdatePacketSize (m_RemoteIdent);
|
|
}
|
|
else
|
|
LogPrint ("SSU unexpected identity size ", identitySize);
|
|
payload += identitySize; // identity
|
|
// TODO: verify signature
|
|
SendI2NPMessage (CreateDeliveryStatusMsg (0));
|
|
Established ();
|
|
}
|
|
|
|
void SSUSession::SendSessionRequest ()
|
|
{
|
|
auto introKey = GetIntroKey ();
|
|
if (!introKey)
|
|
{
|
|
LogPrint ("SSU is not supported");
|
|
return;
|
|
}
|
|
|
|
uint8_t buf[304 + 18]; // 304 bytes for ipv4 (320 for ipv6)
|
|
uint8_t * payload = buf + sizeof (SSUHeader);
|
|
memcpy (payload, m_DHKeysPair->publicKey, 256); // x
|
|
payload[256] = 4; // we assume ipv4
|
|
*(uint32_t *)(payload + 257) = htobe32 (m_RemoteEndpoint.address ().to_v4 ().to_ulong ());
|
|
|
|
uint8_t iv[16];
|
|
CryptoPP::RandomNumberGenerator& rnd = i2p::context.GetRandomNumberGenerator ();
|
|
rnd.GenerateBlock (iv, 16); // random iv
|
|
FillHeaderAndEncrypt (PAYLOAD_TYPE_SESSION_REQUEST, buf, 304, introKey, iv, introKey);
|
|
m_Server.Send (buf, 304, m_RemoteEndpoint);
|
|
}
|
|
|
|
void SSUSession::SendRelayRequest (uint32_t iTag, const uint8_t * iKey)
|
|
{
|
|
auto address = i2p::context.GetRouterInfo ().GetSSUAddress ();
|
|
if (!address)
|
|
{
|
|
LogPrint ("SSU is not supported");
|
|
return;
|
|
}
|
|
|
|
uint8_t buf[96 + 18];
|
|
uint8_t * payload = buf + sizeof (SSUHeader);
|
|
*(uint32_t *)payload = htobe32 (iTag);
|
|
payload += 4;
|
|
*payload = 0; // no address
|
|
payload++;
|
|
*(uint16_t *)payload = 0; // port = 0
|
|
payload += 2;
|
|
*payload = 0; // challenge
|
|
payload++;
|
|
memcpy (payload, (const uint8_t *)address->key, 32);
|
|
payload += 32;
|
|
CryptoPP::RandomNumberGenerator& rnd = i2p::context.GetRandomNumberGenerator ();
|
|
*(uint32_t *)payload = htobe32 (rnd.GenerateWord32 ()); // nonce
|
|
|
|
uint8_t iv[16];
|
|
rnd.GenerateBlock (iv, 16); // random iv
|
|
if (m_State == eSessionStateEstablished)
|
|
FillHeaderAndEncrypt (PAYLOAD_TYPE_RELAY_REQUEST, buf, 96, m_SessionKey, iv, m_MacKey);
|
|
else
|
|
FillHeaderAndEncrypt (PAYLOAD_TYPE_RELAY_REQUEST, buf, 96, iKey, iv, iKey);
|
|
m_Server.Send (buf, 96, m_RemoteEndpoint);
|
|
}
|
|
|
|
void SSUSession::SendSessionCreated (const uint8_t * x)
|
|
{
|
|
auto introKey = GetIntroKey ();
|
|
auto address = i2p::context.GetRouterInfo ().GetSSUAddress ();
|
|
if (!introKey || !address)
|
|
{
|
|
LogPrint ("SSU is not supported");
|
|
return;
|
|
}
|
|
CryptoPP::RandomNumberGenerator& rnd = i2p::context.GetRandomNumberGenerator ();
|
|
uint8_t signedData[532]; // x,y, remote IP, remote port, our IP, our port, relayTag, signed on time
|
|
memcpy (signedData, x, 256); // x
|
|
|
|
uint8_t buf[368 + 18];
|
|
uint8_t * payload = buf + sizeof (SSUHeader);
|
|
memcpy (payload, m_DHKeysPair->publicKey, 256);
|
|
memcpy (signedData + 256, payload, 256); // y
|
|
payload += 256;
|
|
*payload = 4; // we assume ipv4
|
|
payload++;
|
|
*(uint32_t *)(payload) = htobe32 (m_RemoteEndpoint.address ().to_v4 ().to_ulong ());
|
|
payload += 4;
|
|
*(uint16_t *)(payload) = htobe16 (m_RemoteEndpoint.port ());
|
|
payload += 2;
|
|
memcpy (signedData + 512, payload - 6, 6); // remote endpoint IP and port
|
|
*(uint32_t *)(signedData + 518) = htobe32 (address->host.to_v4 ().to_ulong ()); // our IP
|
|
*(uint16_t *)(signedData + 522) = htobe16 (address->port); // our port
|
|
uint32_t relayTag = 0;
|
|
if (i2p::context.GetRouterInfo ().IsIntroducer ())
|
|
{
|
|
relayTag = rnd.GenerateWord32 ();
|
|
if (!relayTag) relayTag = 1;
|
|
m_Server.AddRelay (relayTag, m_RemoteEndpoint);
|
|
}
|
|
*(uint32_t *)(payload) = htobe32 (relayTag);
|
|
payload += 4; // relay tag
|
|
*(uint32_t *)(payload) = htobe32 (i2p::util::GetSecondsSinceEpoch ()); // signed on time
|
|
payload += 4;
|
|
memcpy (signedData + 524, payload - 8, 8); // relayTag and signed on time
|
|
i2p::context.Sign (signedData, 532, payload); // DSA signature
|
|
// TODO: fill padding with random data
|
|
|
|
uint8_t iv[16];
|
|
rnd.GenerateBlock (iv, 16); // random iv
|
|
// encrypt signature and 8 bytes padding with newly created session key
|
|
m_SessionKeyEncryption.SetIV (iv);
|
|
m_SessionKeyEncryption.Encrypt (payload, 48, payload);
|
|
|
|
// encrypt message with intro key
|
|
FillHeaderAndEncrypt (PAYLOAD_TYPE_SESSION_CREATED, buf, 368, introKey, iv, introKey);
|
|
Send (buf, 368);
|
|
}
|
|
|
|
void SSUSession::SendSessionConfirmed (const uint8_t * y, const uint8_t * ourAddress)
|
|
{
|
|
uint8_t buf[480 + 18];
|
|
uint8_t * payload = buf + sizeof (SSUHeader);
|
|
*payload = 1; // 1 fragment
|
|
payload++; // info
|
|
size_t identLen = sizeof (i2p::context.GetRouterIdentity ()); // 387 bytes
|
|
*(uint16_t *)(payload) = htobe16 (identLen);
|
|
payload += 2; // cursize
|
|
memcpy (payload, (uint8_t *)&i2p::context.GetRouterIdentity (), identLen);
|
|
payload += identLen;
|
|
uint32_t signedOnTime = i2p::util::GetSecondsSinceEpoch ();
|
|
*(uint32_t *)(payload) = htobe32 (signedOnTime); // signed on time
|
|
payload += 4;
|
|
size_t paddingSize = ((payload - buf) + 40)%16;
|
|
if (paddingSize > 0) paddingSize = 16 - paddingSize;
|
|
// TODO: fill padding
|
|
payload += paddingSize; // padding size
|
|
|
|
// signature
|
|
uint8_t signedData[532]; // x,y, our IP, our port, remote IP, remote port, relayTag, our signed on time
|
|
memcpy (signedData, m_DHKeysPair->publicKey, 256); // x
|
|
memcpy (signedData + 256, y, 256); // y
|
|
memcpy (signedData + 512, ourAddress, 6); // our address/port as seem by party
|
|
*(uint32_t *)(signedData + 518) = htobe32 (m_RemoteEndpoint.address ().to_v4 ().to_ulong ()); // remote IP
|
|
*(uint16_t *)(signedData + 522) = htobe16 (m_RemoteEndpoint.port ()); // remote port
|
|
*(uint32_t *)(signedData + 524) = htobe32 (m_RelayTag); // relay tag
|
|
*(uint32_t *)(signedData + 528) = htobe32 (signedOnTime); // signed on time
|
|
i2p::context.Sign (signedData, 532, payload); // DSA signature
|
|
|
|
uint8_t iv[16];
|
|
CryptoPP::RandomNumberGenerator& rnd = i2p::context.GetRandomNumberGenerator ();
|
|
rnd.GenerateBlock (iv, 16); // random iv
|
|
// encrypt message with session key
|
|
FillHeaderAndEncrypt (PAYLOAD_TYPE_SESSION_CONFIRMED, buf, 480, m_SessionKey, iv, m_MacKey);
|
|
Send (buf, 480);
|
|
}
|
|
|
|
void SSUSession::ProcessRelayRequest (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& from)
|
|
{
|
|
uint32_t relayTag = be32toh (*(uint32_t *)buf);
|
|
auto session = m_Server.FindRelaySession (relayTag);
|
|
if (session)
|
|
{
|
|
buf += 4; // relay tag
|
|
uint8_t size = *buf;
|
|
buf++; // size
|
|
buf += size; // address
|
|
buf += 2; // port
|
|
uint8_t challengeSize = *buf;
|
|
buf++; // challenge size
|
|
buf += challengeSize;
|
|
uint8_t * introKey = buf;
|
|
buf += 32; // introkey
|
|
uint32_t nonce = be32toh (*(uint32_t *)buf);
|
|
SendRelayResponse (nonce, from, introKey, session->m_RemoteEndpoint);
|
|
SendRelayIntro (session, from);
|
|
}
|
|
}
|
|
|
|
void SSUSession::SendRelayResponse (uint32_t nonce, const boost::asio::ip::udp::endpoint& from,
|
|
const uint8_t * introKey, const boost::asio::ip::udp::endpoint& to)
|
|
{
|
|
uint8_t buf[64 + 18];
|
|
uint8_t * payload = buf + sizeof (SSUHeader);
|
|
// Charlie
|
|
*payload = 4;
|
|
payload++; // size
|
|
*(uint32_t *)payload = htobe32 (to.address ().to_v4 ().to_ulong ()); // Charlie's IP
|
|
payload += 4; // address
|
|
*(uint16_t *)payload = htobe16 (to.port ()); // Charlie's port
|
|
payload += 2; // port
|
|
// Alice
|
|
*payload = 4;
|
|
payload++; // size
|
|
*(uint32_t *)payload = htobe32 (from.address ().to_v4 ().to_ulong ()); // Alice's IP
|
|
payload += 4; // address
|
|
*(uint16_t *)payload = htobe16 (from.port ()); // Alice's port
|
|
payload += 2; // port
|
|
*(uint32_t *)payload = htobe32 (nonce);
|
|
|
|
if (m_State == eSessionStateEstablished)
|
|
{
|
|
// encrypt with session key
|
|
FillHeaderAndEncrypt (PAYLOAD_TYPE_RELAY_RESPONSE, buf, 64);
|
|
Send (buf, 64);
|
|
}
|
|
else
|
|
{
|
|
// ecrypt with Alice's intro key
|
|
uint8_t iv[16];
|
|
CryptoPP::RandomNumberGenerator& rnd = i2p::context.GetRandomNumberGenerator ();
|
|
rnd.GenerateBlock (iv, 16); // random iv
|
|
FillHeaderAndEncrypt (PAYLOAD_TYPE_RELAY_RESPONSE, buf, 64, introKey, iv, introKey);
|
|
m_Server.Send (buf, 64, from);
|
|
}
|
|
LogPrint ("SSU relay response sent");
|
|
}
|
|
|
|
void SSUSession::SendRelayIntro (SSUSession * session, const boost::asio::ip::udp::endpoint& from)
|
|
{
|
|
if (!session) return;
|
|
uint8_t buf[48 + 18];
|
|
uint8_t * payload = buf + sizeof (SSUHeader);
|
|
*payload = 4;
|
|
payload++; // size
|
|
*(uint32_t *)payload = htobe32 (from.address ().to_v4 ().to_ulong ()); // Alice's IP
|
|
payload += 4; // address
|
|
*(uint16_t *)payload = htobe16 (from.port ()); // Alice's port
|
|
payload += 2; // port
|
|
*payload = 0; // challenge size
|
|
uint8_t iv[16];
|
|
CryptoPP::RandomNumberGenerator& rnd = i2p::context.GetRandomNumberGenerator ();
|
|
rnd.GenerateBlock (iv, 16); // random iv
|
|
FillHeaderAndEncrypt (PAYLOAD_TYPE_RELAY_INTRO, buf, 48, session->m_SessionKey, iv, session->m_MacKey);
|
|
m_Server.Send (buf, 48, session->m_RemoteEndpoint);
|
|
LogPrint ("SSU relay intro sent");
|
|
}
|
|
|
|
void SSUSession::ProcessRelayResponse (uint8_t * buf, size_t len)
|
|
{
|
|
LogPrint ("Relay response received");
|
|
uint8_t * payload = buf + sizeof (SSUHeader);
|
|
payload++; // remote size
|
|
//boost::asio::ip::address_v4 remoteIP (be32toh (*(uint32_t* )(payload)));
|
|
payload += 4; // remote address
|
|
//uint16_t remotePort = be16toh (*(uint16_t *)(payload));
|
|
payload += 2; // remote port
|
|
payload++; // our size
|
|
boost::asio::ip::address_v4 ourIP (be32toh (*(uint32_t* )(payload)));
|
|
payload += 4; // our address
|
|
uint16_t ourPort = be16toh (*(uint16_t *)(payload));
|
|
payload += 2; // our port
|
|
LogPrint ("Our external address is ", ourIP.to_string (), ":", ourPort);
|
|
i2p::context.UpdateAddress (ourIP.to_string ().c_str ());
|
|
}
|
|
|
|
void SSUSession::ProcessRelayIntro (uint8_t * buf, size_t len)
|
|
{
|
|
uint8_t size = *buf;
|
|
if (size == 4)
|
|
{
|
|
buf++; // size
|
|
boost::asio::ip::address_v4 address (be32toh (*(uint32_t* )buf));
|
|
buf += 4; // address
|
|
uint16_t port = be16toh (*(uint16_t *)buf);
|
|
// send hole punch of 1 byte
|
|
m_Server.Send (buf, 0, boost::asio::ip::udp::endpoint (address, port));
|
|
}
|
|
else
|
|
LogPrint ("Address size ", size, " is not supported");
|
|
}
|
|
|
|
void SSUSession::FillHeaderAndEncrypt (uint8_t payloadType, uint8_t * buf, size_t len,
|
|
const uint8_t * aesKey, const uint8_t * iv, const uint8_t * macKey)
|
|
{
|
|
if (len < sizeof (SSUHeader))
|
|
{
|
|
LogPrint ("Unexpected SSU packet length ", len);
|
|
return;
|
|
}
|
|
SSUHeader * header = (SSUHeader *)buf;
|
|
memcpy (header->iv, iv, 16);
|
|
header->flag = payloadType << 4; // MSB is 0
|
|
header->time = htobe32 (i2p::util::GetSecondsSinceEpoch ());
|
|
uint8_t * encrypted = &header->flag;
|
|
uint16_t encryptedLen = len - (encrypted - buf);
|
|
i2p::crypto::CBCEncryption encryption;
|
|
encryption.SetKey (aesKey);
|
|
encryption.SetIV (iv);
|
|
encryption.Encrypt (encrypted, encryptedLen, encrypted);
|
|
// assume actual buffer size is 18 (16 + 2) bytes more
|
|
memcpy (buf + len, iv, 16);
|
|
*(uint16_t *)(buf + len + 16) = htobe16 (encryptedLen);
|
|
i2p::crypto::HMACMD5Digest (encrypted, encryptedLen + 18, macKey, header->mac);
|
|
}
|
|
|
|
void SSUSession::FillHeaderAndEncrypt (uint8_t payloadType, uint8_t * buf, size_t len)
|
|
{
|
|
if (len < sizeof (SSUHeader))
|
|
{
|
|
LogPrint ("Unexpected SSU packet length ", len);
|
|
return;
|
|
}
|
|
SSUHeader * header = (SSUHeader *)buf;
|
|
i2p::context.GetRandomNumberGenerator ().GenerateBlock (header->iv, 16); // random iv
|
|
m_SessionKeyEncryption.SetIV (header->iv);
|
|
header->flag = payloadType << 4; // MSB is 0
|
|
header->time = htobe32 (i2p::util::GetSecondsSinceEpoch ());
|
|
uint8_t * encrypted = &header->flag;
|
|
uint16_t encryptedLen = len - (encrypted - buf);
|
|
m_SessionKeyEncryption.Encrypt (encrypted, encryptedLen, encrypted);
|
|
// assume actual buffer size is 18 (16 + 2) bytes more
|
|
memcpy (buf + len, header->iv, 16);
|
|
*(uint16_t *)(buf + len + 16) = htobe16 (encryptedLen);
|
|
i2p::crypto::HMACMD5Digest (encrypted, encryptedLen + 18, m_MacKey, header->mac);
|
|
}
|
|
|
|
void SSUSession::Decrypt (uint8_t * buf, size_t len, const uint8_t * aesKey)
|
|
{
|
|
if (len < sizeof (SSUHeader))
|
|
{
|
|
LogPrint ("Unexpected SSU packet length ", len);
|
|
return;
|
|
}
|
|
SSUHeader * header = (SSUHeader *)buf;
|
|
uint8_t * encrypted = &header->flag;
|
|
uint16_t encryptedLen = len - (encrypted - buf);
|
|
i2p::crypto::CBCDecryption decryption;
|
|
decryption.SetKey (aesKey);
|
|
decryption.SetIV (header->iv);
|
|
decryption.Decrypt (encrypted, encryptedLen, encrypted);
|
|
}
|
|
|
|
void SSUSession::DecryptSessionKey (uint8_t * buf, size_t len)
|
|
{
|
|
if (len < sizeof (SSUHeader))
|
|
{
|
|
LogPrint ("Unexpected SSU packet length ", len);
|
|
return;
|
|
}
|
|
SSUHeader * header = (SSUHeader *)buf;
|
|
uint8_t * encrypted = &header->flag;
|
|
uint16_t encryptedLen = len - (encrypted - buf);
|
|
if (encryptedLen > 0)
|
|
{
|
|
m_SessionKeyDecryption.SetIV (header->iv);
|
|
m_SessionKeyDecryption.Decrypt (encrypted, encryptedLen, encrypted);
|
|
}
|
|
}
|
|
|
|
bool SSUSession::Validate (uint8_t * buf, size_t len, const uint8_t * macKey)
|
|
{
|
|
if (len < sizeof (SSUHeader))
|
|
{
|
|
LogPrint ("Unexpected SSU packet length ", len);
|
|
return false;
|
|
}
|
|
SSUHeader * header = (SSUHeader *)buf;
|
|
uint8_t * encrypted = &header->flag;
|
|
uint16_t encryptedLen = len - (encrypted - buf);
|
|
// assume actual buffer size is 18 (16 + 2) bytes more
|
|
memcpy (buf + len, header->iv, 16);
|
|
*(uint16_t *)(buf + len + 16) = htobe16 (encryptedLen);
|
|
uint8_t digest[16];
|
|
i2p::crypto::HMACMD5Digest (encrypted, encryptedLen + 18, macKey, digest);
|
|
return !memcmp (header->mac, digest, 16);
|
|
}
|
|
|
|
void SSUSession::Connect ()
|
|
{
|
|
if (m_State == eSessionStateUnknown)
|
|
{
|
|
// set connect timer
|
|
ScheduleConnectTimer ();
|
|
m_DHKeysPair = i2p::transports.GetNextDHKeysPair ();
|
|
SendSessionRequest ();
|
|
}
|
|
}
|
|
|
|
void SSUSession::ScheduleConnectTimer ()
|
|
{
|
|
m_Timer.cancel ();
|
|
m_Timer.expires_from_now (boost::posix_time::seconds(SSU_CONNECT_TIMEOUT));
|
|
m_Timer.async_wait (boost::bind (&SSUSession::HandleConnectTimer,
|
|
this, boost::asio::placeholders::error));
|
|
}
|
|
|
|
void SSUSession::HandleConnectTimer (const boost::system::error_code& ecode)
|
|
{
|
|
if (!ecode)
|
|
{
|
|
// timeout expired
|
|
LogPrint ("SSU session was not established after ", SSU_CONNECT_TIMEOUT, " second");
|
|
Failed ();
|
|
}
|
|
}
|
|
|
|
void SSUSession::Introduce (uint32_t iTag, const uint8_t * iKey)
|
|
{
|
|
if (m_State == eSessionStateUnknown)
|
|
{
|
|
// set connect timer
|
|
m_Timer.expires_from_now (boost::posix_time::seconds(SSU_CONNECT_TIMEOUT));
|
|
m_Timer.async_wait (boost::bind (&SSUSession::HandleConnectTimer,
|
|
this, boost::asio::placeholders::error));
|
|
}
|
|
SendRelayRequest (iTag, iKey);
|
|
}
|
|
|
|
void SSUSession::WaitForIntroduction ()
|
|
{
|
|
m_State = eSessionStateIntroduced;
|
|
// set connect timer
|
|
m_Timer.expires_from_now (boost::posix_time::seconds(SSU_CONNECT_TIMEOUT));
|
|
m_Timer.async_wait (boost::bind (&SSUSession::HandleConnectTimer,
|
|
this, boost::asio::placeholders::error));
|
|
}
|
|
|
|
void SSUSession::Close ()
|
|
{
|
|
SendSesionDestroyed ();
|
|
if (!m_DelayedMessages.empty ())
|
|
{
|
|
for (auto it :m_DelayedMessages)
|
|
DeleteI2NPMessage (it);
|
|
m_DelayedMessages.clear ();
|
|
}
|
|
}
|
|
|
|
void SSUSession::Established ()
|
|
{
|
|
m_State = eSessionStateEstablished;
|
|
if (m_DHKeysPair)
|
|
{
|
|
delete m_DHKeysPair;
|
|
m_DHKeysPair = nullptr;
|
|
}
|
|
SendI2NPMessage (CreateDatabaseStoreMsg ());
|
|
if (!m_DelayedMessages.empty ())
|
|
{
|
|
for (auto it :m_DelayedMessages)
|
|
m_Data.Send (it);
|
|
m_DelayedMessages.clear ();
|
|
}
|
|
if (m_PeerTest && (m_RemoteRouter && m_RemoteRouter->IsPeerTesting ()))
|
|
SendPeerTest ();
|
|
ScheduleTermination ();
|
|
}
|
|
|
|
void SSUSession::Failed ()
|
|
{
|
|
if (m_State != eSessionStateFailed)
|
|
{
|
|
m_State = eSessionStateFailed;
|
|
m_Server.DeleteSession (this); // delete this
|
|
}
|
|
}
|
|
|
|
void SSUSession::ScheduleTermination ()
|
|
{
|
|
m_Timer.cancel ();
|
|
m_Timer.expires_from_now (boost::posix_time::seconds(SSU_TERMINATION_TIMEOUT));
|
|
m_Timer.async_wait (boost::bind (&SSUSession::HandleTerminationTimer,
|
|
this, boost::asio::placeholders::error));
|
|
}
|
|
|
|
void SSUSession::HandleTerminationTimer (const boost::system::error_code& ecode)
|
|
{
|
|
if (ecode != boost::asio::error::operation_aborted)
|
|
{
|
|
LogPrint ("SSU no activity fo ", SSU_TERMINATION_TIMEOUT, " seconds");
|
|
Failed ();
|
|
}
|
|
}
|
|
|
|
const uint8_t * SSUSession::GetIntroKey () const
|
|
{
|
|
if (m_RemoteRouter)
|
|
{
|
|
// we are client
|
|
auto address = m_RemoteRouter->GetSSUAddress ();
|
|
return address ? (const uint8_t *)address->key : nullptr;
|
|
}
|
|
else
|
|
{
|
|
// we are server
|
|
auto address = i2p::context.GetRouterInfo ().GetSSUAddress ();
|
|
return address ? (const uint8_t *)address->key : nullptr;
|
|
}
|
|
}
|
|
|
|
void SSUSession::SendI2NPMessage (I2NPMessage * msg)
|
|
{
|
|
m_Server.GetService ().post (boost::bind (&SSUSession::PostI2NPMessage, this, msg));
|
|
}
|
|
|
|
void SSUSession::PostI2NPMessage (I2NPMessage * msg)
|
|
{
|
|
if (msg)
|
|
{
|
|
if (m_State == eSessionStateEstablished)
|
|
m_Data.Send (msg);
|
|
else
|
|
m_DelayedMessages.push_back (msg);
|
|
}
|
|
}
|
|
|
|
void SSUSession::ProcessData (uint8_t * buf, size_t len)
|
|
{
|
|
m_Data.ProcessMessage (buf, len);
|
|
}
|
|
|
|
|
|
void SSUSession::ProcessPeerTest (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& senderEndpoint)
|
|
{
|
|
uint8_t * buf1 = buf;
|
|
uint32_t nonce = be32toh (*(uint32_t *)buf);
|
|
buf += 4; // nonce
|
|
uint8_t size = *buf;
|
|
buf++; // size
|
|
uint8_t * address = (size == 4) ? buf : nullptr;
|
|
buf += size; // address
|
|
uint16_t port = *(uint16_t *)buf; // use it as is
|
|
buf += 2; // port
|
|
uint8_t * introKey = buf;
|
|
if (port && !address)
|
|
{
|
|
LogPrint ("Address of ", size, " bytes not supported");
|
|
return;
|
|
}
|
|
if (m_PeerTestNonces.count (nonce) > 0)
|
|
{
|
|
// existing test
|
|
if (m_PeerTest)
|
|
{
|
|
LogPrint ("SSU peer test from Bob. We are Alice");
|
|
m_PeerTestNonces.erase (nonce);
|
|
m_PeerTest = false;
|
|
}
|
|
else if (port)
|
|
{
|
|
LogPrint ("SSU peer test from Charlie. We are Bob");
|
|
boost::asio::ip::udp::endpoint ep (boost::asio::ip::address_v4 (be32toh (*(uint32_t *)address)), be16toh (port)); // Alice's address/port
|
|
auto session = m_Server.FindSession (ep); // find session with Alice
|
|
if (session)
|
|
session->Send (PAYLOAD_TYPE_PEER_TEST, buf1, len); // back to Alice
|
|
}
|
|
else
|
|
{
|
|
LogPrint ("SSU peer test from Alice. We are Charlie");
|
|
SendPeerTest (nonce, senderEndpoint.address ().to_v4 ().to_ulong (),
|
|
senderEndpoint.port (), introKey); // to Alice
|
|
}
|
|
}
|
|
else
|
|
{
|
|
// new test
|
|
m_PeerTestNonces.insert (nonce);
|
|
if (port)
|
|
{
|
|
LogPrint ("SSU peer test from Bob. We are Charlie");
|
|
Send (PAYLOAD_TYPE_PEER_TEST, buf1, len); // back to Bob
|
|
SendPeerTest (nonce, be32toh (*(uint32_t *)address), be16toh (port), introKey); // to Alice
|
|
}
|
|
else
|
|
{
|
|
LogPrint ("SSU peer test from Alice. We are Bob");
|
|
auto session = m_Server.GetRandomEstablishedSession (this); // charlie
|
|
if (session)
|
|
session->SendPeerTest (nonce, senderEndpoint.address ().to_v4 ().to_ulong (),
|
|
senderEndpoint.port (), introKey, false);
|
|
}
|
|
}
|
|
}
|
|
|
|
void SSUSession::SendPeerTest (uint32_t nonce, uint32_t address, uint16_t port,
|
|
const uint8_t * introKey, bool toAddress)
|
|
{
|
|
uint8_t buf[80 + 18];
|
|
uint8_t iv[16];
|
|
uint8_t * payload = buf + sizeof (SSUHeader);
|
|
*(uint32_t *)payload = htobe32 (nonce);
|
|
payload += 4; // nonce
|
|
*payload = 4;
|
|
payload++; // size
|
|
*(uint32_t *)payload = htobe32 (address);
|
|
payload += 4; // address
|
|
*(uint16_t *)payload = htobe16 (port);
|
|
payload += 2; // port
|
|
memcpy (payload, introKey, 32); // intro key
|
|
|
|
CryptoPP::RandomNumberGenerator& rnd = i2p::context.GetRandomNumberGenerator ();
|
|
rnd.GenerateBlock (iv, 16); // random iv
|
|
if (toAddress)
|
|
{
|
|
// encrypt message with specified intro key
|
|
FillHeaderAndEncrypt (PAYLOAD_TYPE_PEER_TEST, buf, 80, introKey, iv, introKey);
|
|
boost::asio::ip::udp::endpoint e (boost::asio::ip::address_v4 (address), port);
|
|
m_Server.Send (buf, 80, e);
|
|
}
|
|
else
|
|
{
|
|
// encrypt message with session key
|
|
FillHeaderAndEncrypt (PAYLOAD_TYPE_PEER_TEST, buf, 80);
|
|
Send (buf, 80);
|
|
}
|
|
}
|
|
|
|
void SSUSession::SendPeerTest ()
|
|
{
|
|
LogPrint ("SSU sending peer test");
|
|
auto address = i2p::context.GetRouterInfo ().GetSSUAddress ();
|
|
if (!address)
|
|
{
|
|
LogPrint ("SSU is not supported. Can't send peer test");
|
|
return;
|
|
}
|
|
uint32_t nonce = i2p::context.GetRandomNumberGenerator ().GenerateWord32 ();
|
|
if (!nonce) nonce = 1;
|
|
m_PeerTestNonces.insert (nonce);
|
|
SendPeerTest (nonce, 0, 0, address->key, false); // address and port always zero for Alice
|
|
}
|
|
|
|
void SSUSession::SendKeepAlive ()
|
|
{
|
|
if (m_State == eSessionStateEstablished)
|
|
{
|
|
uint8_t buf[48 + 18];
|
|
uint8_t * payload = buf + sizeof (SSUHeader);
|
|
*payload = 0; // flags
|
|
payload++;
|
|
*payload = 0; // num fragments
|
|
// encrypt message with session key
|
|
FillHeaderAndEncrypt (PAYLOAD_TYPE_DATA, buf, 48);
|
|
Send (buf, 48);
|
|
LogPrint ("SSU keep-alive sent");
|
|
ScheduleTermination ();
|
|
}
|
|
}
|
|
|
|
void SSUSession::SendSesionDestroyed ()
|
|
{
|
|
if (m_IsSessionKey)
|
|
{
|
|
uint8_t buf[48 + 18];
|
|
// encrypt message with session key
|
|
FillHeaderAndEncrypt (PAYLOAD_TYPE_SESSION_DESTROYED, buf, 48);
|
|
Send (buf, 48);
|
|
LogPrint ("SSU session destroyed sent");
|
|
}
|
|
}
|
|
|
|
void SSUSession::Send (uint8_t type, const uint8_t * payload, size_t len)
|
|
{
|
|
uint8_t buf[SSU_MTU + 18];
|
|
size_t msgSize = len + sizeof (SSUHeader);
|
|
if (msgSize > SSU_MTU)
|
|
{
|
|
LogPrint ("SSU payload size ", msgSize, " exceeds MTU");
|
|
return;
|
|
}
|
|
memcpy (buf + sizeof (SSUHeader), payload, len);
|
|
// encrypt message with session key
|
|
FillHeaderAndEncrypt (type, buf, msgSize);
|
|
Send (buf, msgSize);
|
|
}
|
|
|
|
void SSUSession::Send (const uint8_t * buf, size_t size)
|
|
{
|
|
m_NumSentBytes += size;
|
|
m_Server.Send (buf, size, m_RemoteEndpoint);
|
|
}
|
|
|
|
|
|
SSUServer::SSUServer (int port): m_Thread (nullptr), m_Work (m_Service),
|
|
m_Endpoint (boost::asio::ip::udp::v4 (), port), m_Socket (m_Service, m_Endpoint),
|
|
m_IntroducersUpdateTimer (m_Service)
|
|
{
|
|
m_Socket.set_option (boost::asio::socket_base::receive_buffer_size (65535));
|
|
m_Socket.set_option (boost::asio::socket_base::send_buffer_size (65535));
|
|
}
|
|
|
|
SSUServer::~SSUServer ()
|
|
{
|
|
for (auto it: m_Sessions)
|
|
delete it.second;
|
|
}
|
|
|
|
void SSUServer::Start ()
|
|
{
|
|
m_IsRunning = true;
|
|
m_Thread = new std::thread (std::bind (&SSUServer::Run, this));
|
|
m_Service.post (boost::bind (&SSUServer::Receive, this));
|
|
if (i2p::context.IsUnreachable ())
|
|
ScheduleIntroducersUpdateTimer ();
|
|
}
|
|
|
|
void SSUServer::Stop ()
|
|
{
|
|
DeleteAllSessions ();
|
|
m_IsRunning = false;
|
|
m_Service.stop ();
|
|
m_Socket.close ();
|
|
if (m_Thread)
|
|
{
|
|
m_Thread->join ();
|
|
delete m_Thread;
|
|
m_Thread = 0;
|
|
}
|
|
}
|
|
|
|
void SSUServer::Run ()
|
|
{
|
|
while (m_IsRunning)
|
|
{
|
|
try
|
|
{
|
|
m_Service.run ();
|
|
}
|
|
catch (std::exception& ex)
|
|
{
|
|
LogPrint ("SSU server: ", ex.what ());
|
|
}
|
|
}
|
|
}
|
|
|
|
void SSUServer::AddRelay (uint32_t tag, const boost::asio::ip::udp::endpoint& relay)
|
|
{
|
|
m_Relays[tag] = relay;
|
|
}
|
|
|
|
SSUSession * SSUServer::FindRelaySession (uint32_t tag)
|
|
{
|
|
auto it = m_Relays.find (tag);
|
|
if (it != m_Relays.end ())
|
|
return FindSession (it->second);
|
|
return nullptr;
|
|
}
|
|
|
|
void SSUServer::Send (const uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& to)
|
|
{
|
|
m_Socket.send_to (boost::asio::buffer (buf, len), to);
|
|
}
|
|
|
|
void SSUServer::Receive ()
|
|
{
|
|
m_Socket.async_receive_from (boost::asio::buffer (m_ReceiveBuffer, SSU_MTU), m_SenderEndpoint,
|
|
boost::bind (&SSUServer::HandleReceivedFrom, this, boost::asio::placeholders::error, boost::asio::placeholders::bytes_transferred));
|
|
}
|
|
|
|
void SSUServer::HandleReceivedFrom (const boost::system::error_code& ecode, std::size_t bytes_transferred)
|
|
{
|
|
if (!ecode)
|
|
{
|
|
SSUSession * session = nullptr;
|
|
auto it = m_Sessions.find (m_SenderEndpoint);
|
|
if (it != m_Sessions.end ())
|
|
session = it->second;
|
|
if (!session)
|
|
{
|
|
session = new SSUSession (*this, m_SenderEndpoint);
|
|
m_Sessions[m_SenderEndpoint] = session;
|
|
LogPrint ("New SSU session from ", m_SenderEndpoint.address ().to_string (), ":", m_SenderEndpoint.port (), " created");
|
|
}
|
|
session->ProcessNextMessage (m_ReceiveBuffer, bytes_transferred, m_SenderEndpoint);
|
|
Receive ();
|
|
}
|
|
else
|
|
LogPrint ("SSU receive error: ", ecode.message ());
|
|
}
|
|
|
|
SSUSession * SSUServer::FindSession (const i2p::data::RouterInfo * router)
|
|
{
|
|
if (!router) return nullptr;
|
|
auto address = router->GetSSUAddress ();
|
|
if (!address) return nullptr;
|
|
return FindSession (boost::asio::ip::udp::endpoint (address->host, address->port));
|
|
}
|
|
|
|
SSUSession * SSUServer::FindSession (const boost::asio::ip::udp::endpoint& e)
|
|
{
|
|
auto it = m_Sessions.find (e);
|
|
if (it != m_Sessions.end ())
|
|
return it->second;
|
|
else
|
|
return nullptr;
|
|
}
|
|
|
|
SSUSession * SSUServer::GetSession (const i2p::data::RouterInfo * router, bool peerTest)
|
|
{
|
|
SSUSession * session = nullptr;
|
|
if (router)
|
|
{
|
|
auto address = router->GetSSUAddress ();
|
|
if (address)
|
|
{
|
|
boost::asio::ip::udp::endpoint remoteEndpoint (address->host, address->port);
|
|
auto it = m_Sessions.find (remoteEndpoint);
|
|
if (it != m_Sessions.end ())
|
|
session = it->second;
|
|
else
|
|
{
|
|
// otherwise create new session
|
|
session = new SSUSession (*this, remoteEndpoint, router, peerTest);
|
|
m_Sessions[remoteEndpoint] = session;
|
|
|
|
if (!router->UsesIntroducer ())
|
|
{
|
|
// connect directly
|
|
LogPrint ("Creating new SSU session to [", router->GetIdentHashAbbreviation (), "] ",
|
|
remoteEndpoint.address ().to_string (), ":", remoteEndpoint.port ());
|
|
session->Connect ();
|
|
}
|
|
else
|
|
{
|
|
// connect through introducer
|
|
int numIntroducers = address->introducers.size ();
|
|
if (numIntroducers > 0)
|
|
{
|
|
SSUSession * introducerSession = nullptr;
|
|
const i2p::data::RouterInfo::Introducer * introducer = nullptr;
|
|
// we might have a session to introducer already
|
|
for (int i = 0; i < numIntroducers; i++)
|
|
{
|
|
introducer = &(address->introducers[i]);
|
|
it = m_Sessions.find (boost::asio::ip::udp::endpoint (introducer->iHost, introducer->iPort));
|
|
if (it != m_Sessions.end ())
|
|
{
|
|
introducerSession = it->second;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (introducerSession) // session found
|
|
LogPrint ("Session to introducer already exists");
|
|
else // create new
|
|
{
|
|
LogPrint ("Creating new session to introducer");
|
|
introducer = &(address->introducers[0]); // TODO:
|
|
boost::asio::ip::udp::endpoint introducerEndpoint (introducer->iHost, introducer->iPort);
|
|
introducerSession = new SSUSession (*this, introducerEndpoint, router);
|
|
m_Sessions[introducerEndpoint] = introducerSession;
|
|
}
|
|
// introduce
|
|
LogPrint ("Introduce new SSU session to [", router->GetIdentHashAbbreviation (),
|
|
"] through introducer ", introducer->iHost, ":", introducer->iPort);
|
|
session->WaitForIntroduction ();
|
|
if (i2p::context.GetRouterInfo ().UsesIntroducer ()) // if we are unreachable
|
|
Send (m_ReceiveBuffer, 0, remoteEndpoint); // send HolePunch
|
|
introducerSession->Introduce (introducer->iTag, introducer->iKey);
|
|
}
|
|
else
|
|
{
|
|
LogPrint ("Can't connect to unreachable router. No introducers presented");
|
|
m_Sessions.erase (remoteEndpoint);
|
|
delete session;
|
|
session = nullptr;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
else
|
|
LogPrint ("Router ", router->GetIdentHashAbbreviation (), " doesn't have SSU address");
|
|
}
|
|
return session;
|
|
}
|
|
|
|
void SSUServer::DeleteSession (SSUSession * session)
|
|
{
|
|
if (session)
|
|
{
|
|
session->Close ();
|
|
m_Sessions.erase (session->GetRemoteEndpoint ());
|
|
delete session;
|
|
}
|
|
}
|
|
|
|
void SSUServer::DeleteAllSessions ()
|
|
{
|
|
for (auto it: m_Sessions)
|
|
{
|
|
it.second->Close ();
|
|
delete it.second;
|
|
}
|
|
m_Sessions.clear ();
|
|
}
|
|
|
|
template<typename Filter>
|
|
SSUSession * SSUServer::GetRandomSession (Filter filter)
|
|
{
|
|
std::vector<SSUSession *> filteredSessions;
|
|
for (auto s :m_Sessions)
|
|
if (filter (s.second)) filteredSessions.push_back (s.second);
|
|
if (filteredSessions.size () > 0)
|
|
{
|
|
auto ind = i2p::context.GetRandomNumberGenerator ().GenerateWord32 (0, filteredSessions.size ()-1);
|
|
return filteredSessions[ind];
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
SSUSession * SSUServer::GetRandomEstablishedSession (const SSUSession * excluded)
|
|
{
|
|
return GetRandomSession (
|
|
[excluded](SSUSession * session)->bool
|
|
{
|
|
return session->GetState () == eSessionStateEstablished &&
|
|
session != excluded;
|
|
}
|
|
);
|
|
}
|
|
|
|
std::set<SSUSession *> SSUServer::FindIntroducers (int maxNumIntroducers)
|
|
{
|
|
uint32_t ts = i2p::util::GetSecondsSinceEpoch ();
|
|
std::set<SSUSession *> ret;
|
|
for (int i = 0; i < maxNumIntroducers; i++)
|
|
{
|
|
auto session = GetRandomSession (
|
|
[&ret, ts](SSUSession * session)->bool
|
|
{
|
|
return session->GetRelayTag () && !ret.count (session) &&
|
|
session->GetState () == eSessionStateEstablished &&
|
|
ts < session->GetCreationTime () + SSU_TO_INTRODUCER_SESSION_DURATION;
|
|
}
|
|
);
|
|
if (session)
|
|
{
|
|
ret.insert (session);
|
|
break;
|
|
}
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
void SSUServer::ScheduleIntroducersUpdateTimer ()
|
|
{
|
|
m_IntroducersUpdateTimer.expires_from_now (boost::posix_time::seconds(SSU_KEEP_ALIVE_INTERVAL));
|
|
m_IntroducersUpdateTimer.async_wait (boost::bind (&SSUServer::HandleIntroducersUpdateTimer,
|
|
this, boost::asio::placeholders::error));
|
|
}
|
|
|
|
void SSUServer::HandleIntroducersUpdateTimer (const boost::system::error_code& ecode)
|
|
{
|
|
if (!ecode)
|
|
{
|
|
// timeout expired
|
|
std::list<boost::asio::ip::udp::endpoint> newList;
|
|
size_t numIntroducers = 0;
|
|
uint32_t ts = i2p::util::GetSecondsSinceEpoch ();
|
|
for (auto it :m_Introducers)
|
|
{
|
|
auto session = FindSession (it);
|
|
if (session && ts < session->GetCreationTime () + SSU_TO_INTRODUCER_SESSION_DURATION)
|
|
{
|
|
session->SendKeepAlive ();
|
|
newList.push_back (it);
|
|
numIntroducers++;
|
|
}
|
|
else
|
|
i2p::context.RemoveIntroducer (it);
|
|
}
|
|
|
|
if (numIntroducers < SSU_MAX_NUM_INTRODUCERS)
|
|
{
|
|
// create new
|
|
auto introducers = FindIntroducers (SSU_MAX_NUM_INTRODUCERS);
|
|
if (introducers.size () > 0)
|
|
{
|
|
for (auto it1: introducers)
|
|
{
|
|
auto router = it1->GetRemoteRouter ();
|
|
if (router && i2p::context.AddIntroducer (*router, it1->GetRelayTag ()))
|
|
{
|
|
newList.push_back (it1->GetRemoteEndpoint ());
|
|
if (newList.size () >= SSU_MAX_NUM_INTRODUCERS) break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
m_Introducers = newList;
|
|
ScheduleIntroducersUpdateTimer ();
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|