public void Start()
{
Task.Run(() =>
{
TCPFrame tcpFrame;
while (receivedFrameQueue.TryTake(out tcpFrame, TimeSpan.FromSeconds(30)))
{
logger.Debug("{0} receive frame, SEQ: {1}, ACK: {2}", id, tcpFrame.SequenceNumber, tcpFrame.AcknowledgementNumber);
TCPFrame responseTCPFrame;
if (getNextFrame(tcpFrame, out responseTCPFrame))
{
var responseIPFrame = new IPv4Frame();
responseIPFrame.SourceAddress = e.Address;
responseIPFrame.DestinationAddress = s.Address;
responseIPFrame.Protocol = IPProtocol.TCP;
responseIPFrame.EncapsulatedFrame = responseTCPFrame;
responseTCPFrame.Checksum = responseTCPFrame.CalculateChecksum(responseIPFrame.GetPseudoHeader());
logger.Debug("{0} send frame to {1}:{2} from {3}:{4}",
id,
responseIPFrame.DestinationAddress, responseTCPFrame.DestinationPort,
responseIPFrame.SourceAddress, responseTCPFrame.SourcePort);
tap.Write(responseIPFrame.FrameBytes, 0, responseIPFrame.Length);
tap.Flush();
}
}
});
}
public void forwardFrame(IPFrame frame)
{
var id = RandomString(10);
var udpFrame = (UDPFrame)frame.EncapsulatedFrame;
var e = new System.Net.IPEndPoint(System.Net.IPAddress.Parse("192.168.1.220"), udpFrame.DestinationPort);
logger.Debug("{0} Source Port: {1}", id, udpFrame.SourcePort);
logger.Debug("{0} Dest Port: {1}", id, udpFrame.DestinationPort);
ProxySocket socket;
var cacheKey = string.Format("{0}:{1}->{2}", udpFrame.SourcePort, udpFrame.DestinationPort, e.ToString());
if (!natTable.TryGetValue(cacheKey, out socket))
{
socket = new ProxySocket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
socket.ProxyEndPoint = new System.Net.IPEndPoint(System.Net.IPAddress.Parse("192.168.1.150"), 1080);
socket.ProxyType = ProxyTypes.Socks5;
socket.Connect(e);
Task.Run(() =>
{
try
{
logger.Debug("{0} Create a new UDP Receive Task", id);
var buffer = new byte[8192];
ProxySocket tmp;
while (natTable.TryGetValue(cacheKey, out tmp))
{
logger.Debug("start receive");
var bytesReceived = socket.Receive(buffer);
logger.Debug("{0} Received packet", id);
natTable.Add(cacheKey, socket);
var receivedIPFrame = new IPv4Frame();
receivedIPFrame.SourceAddress = frame.DestinationAddress;
receivedIPFrame.DestinationAddress = frame.SourceAddress;
receivedIPFrame.Protocol = IPProtocol.UDP;
var receivedUDPFrame = new UDPFrame();
receivedUDPFrame.SourcePort = udpFrame.DestinationPort;
receivedUDPFrame.DestinationPort = udpFrame.SourcePort;
logger.Debug("{0} RSource Port: {1}", id, receivedUDPFrame.SourcePort);
logger.Debug("{0} RDest Port: {1}", id, receivedUDPFrame.DestinationPort);
receivedUDPFrame.EncapsulatedFrame = new RawDataFrame(buffer, 0, bytesReceived);
receivedIPFrame.EncapsulatedFrame = receivedUDPFrame;
receivedUDPFrame.Checksum = receivedUDPFrame.CalculateChecksum(receivedIPFrame.GetPseudoHeader());
tap.Write(receivedIPFrame.FrameBytes, 0, receivedIPFrame.Length);
tap.Flush();
logger.Debug("{0} wrote", id);
}
}
catch (SocketException err)
{
logger.Error(err);
}
});
}
natTable.Add(cacheKey, socket);
socket.BeginSend(udpFrame.EncapsulatedFrame.FrameBytes, 0, udpFrame.EncapsulatedFrame.FrameBytes.Length, 0, ar =>
{
socket.EndSend(ar);
logger.Debug("{0} Sent to Dest", id);
}, null);
}
