private async Task StartConnect(int port)
{
SaeaAwaitable tcpSaea = null;
try
{
tcpSaea = _argsPool.Rent();
var realSaea = tcpSaea.Saea;
realSaea.RemoteEndPoint = SocketUtil.GetEndPoint("127.0.0.1", port);
tcpSaea.PrepareSAEABuffer(_firstPacket, _firstPacketLength);
var ret = await _remote.ConnectAsync(tcpSaea);
if (ret != SocketError.Success)
{
Close();
return;
}
Task.Factory.StartNew(StartPipe, TaskCreationOptions.PreferFairness).Forget();
}
catch (Exception e)
{
Logging.LogUsefulException(e);
Close();
}
finally
{
_argsPool.Return(tcpSaea);
tcpSaea = null;
}
}
private async Task HandshakeSendResponse()
{
SaeaAwaitable tcpSaea = null;
try
{
if (_firstPacketLength <= 1)
{
Logging.Debug("Invalid first packet length");
Close();
return;
}
byte[] response = TCPRelay.Sock5HandshakeResponseSuccess;
if (_firstPacket[0] != 5)
{
// reject socks 4
response = TCPRelay.Sock5HandshakeResponseReject;
Logging.Error("socks 5 protocol error");
}
tcpSaea = _argsPool.Rent();
tcpSaea.PrepareSAEABuffer(response, response.Length);
var token = await _localSocket.FullSendTaskAsync(tcpSaea, response.Length);
var err = token.SocketError;
var bytesSent = token.BytesTotalTransferred;
Logging.Debug($"HandshakeSendResponse: {err},{bytesSent}");
if (err != SocketError.Success)
{
Close();
return;
}
_argsPool.Return(tcpSaea);
tcpSaea = null;
Debug.Assert(bytesSent == response.Length);
Task.Factory.StartNew(async() => { await Sock5RequestRecv(); }).Forget();
}
catch (Exception e)
{
Logging.LogUsefulException(e);
Close();
}
finally
{
_argsPool.Return(tcpSaea);
tcpSaea = null;
}
}
private async Task Sock5ConnectResponseSend()
{
SaeaAwaitable tcpSaea = null;
try
{
tcpSaea = _argsPool.Rent();
tcpSaea.PrepareSAEABuffer(TCPRelay.Sock5ConnectRequestReplySuccess,
TCPRelay.Sock5ConnectRequestReplySuccess.Length);
var token = await _localSocket.FullSendTaskAsync(tcpSaea,
TCPRelay.Sock5ConnectRequestReplySuccess.Length);
var err = token.SocketError;
var bytesSent = token.BytesTotalTransferred;
Logging.Debug($"Sock5ConnectResponseSend: {err},{bytesSent}");
if (err != SocketError.Success)
{
Close();
return;
}
_argsPool.Return(tcpSaea);
tcpSaea = null;
Debug.Assert(bytesSent == TCPRelay.Sock5ConnectRequestReplySuccess.Length);
Task.Factory.StartNew(async() => { await StartConnect(); }).Forget();
}
catch (Exception e)
{
Logging.LogUsefulException(e);
Close();
}
finally
{
_argsPool.Return(tcpSaea);
tcpSaea = null;
}
}
private async Task HandleUDPAssociate()
{
IPEndPoint endPoint = (IPEndPoint)_localSocket.LocalEndPoint;
IPAddress endPointAddress = endPoint.Address;
if (endPointAddress.IsIPv4MappedToIPv6)
{
endPointAddress = endPointAddress.MapToIPv4();
}
byte[] address = endPointAddress.GetAddressBytes();
int port = endPoint.Port;
byte[] response = new byte[4 + address.Length + ADDR_PORT_LEN];
response[0] = 5;
switch (endPointAddress.AddressFamily)
{
case AddressFamily.InterNetwork:
response[3] = ATYP_IPv4;
break;
case AddressFamily.InterNetworkV6:
response[3] = ATYP_IPv6;
break;
}
Array.Copy(address, 0, response, 4, address.Length);
response[response.Length - 1] = (byte)(port & 0xFF);
response[response.Length - 2] = (byte)((port >> 8) & 0xFF);
SaeaAwaitable tcpSaea = null;
SaeaAwaitable circularRecvSaea = null;
try
{
tcpSaea = _argsPool.Rent();
tcpSaea.PrepareSAEABuffer(response, response.Length);
var token = await _localSocket.FullSendTaskAsync(tcpSaea, response.Length);
var err = token.SocketError;
var sentSize = token.BytesTotalTransferred;
Logging.Debug($"Udp assoc local send: {err},{sentSize}");
if (err != SocketError.Success)
{
Close();
return;
}
Debug.Assert(sentSize == response.Length);
_argsPool.Return(tcpSaea);
tcpSaea = null;
circularRecvSaea = _argsPool.Rent();
while (IsRunning)
{
// UDP Assoc: Read all from socket and wait until client closes the connection
token = await _localSocket.FullReceiveTaskAsync(circularRecvSaea, TCPRelay.RecvSize);
Logging.Debug($"udp assoc local recv: {err}");
var ret = token.SocketError;
var bytesRecved = token.BytesTotalTransferred;
if (ret != SocketError.Success)
{
Logging.Error($"udp assoc: {ret},{bytesRecved}");
Close();
return;
}
if (bytesRecved <= 0)
{
Close();
return;
}
circularRecvSaea.ClearAndResetSaeaProperties();
}
_argsPool.Return(circularRecvSaea);
circularRecvSaea = null;
}
catch (Exception e)
{
Logging.LogUsefulException(e);
Close();
}
finally
{
_argsPool.Return(tcpSaea);
tcpSaea = null;
_argsPool.Return(circularRecvSaea);
circularRecvSaea = null;
}
}