private PortInfo ParsePortInfo(Packet responce)
{
TcpDatagram datagram = responce.Ethernet.IpV4.Tcp;
TcpControlBits bits = responce.Ethernet.IpV4.Tcp.ControlBits;
bool isSynAck = bits.HasFlag(TcpControlBits.Acknowledgment) &&
bits.HasFlag(TcpControlBits.Synchronize);
PortInfo info = new PortInfo(datagram.SourcePort, isSynAck);
return(info);
}
private void ReceivePackets(object arg)
{
CancellationToken ct = (CancellationToken)arg;
using (PacketCommunicator communicator = options.Device.Open(65535, PacketDeviceOpenAttributes.Promiscuous | PacketDeviceOpenAttributes.NoCaptureLocal, 100))
{
communicator.SetFilter("tcp and src " + options.TargetIP + " and dst " + options.SourceIP);
while (true)
{
if (ct.IsCancellationRequested)
{
return;
}
Packet responce;
PacketCommunicatorReceiveResult result = communicator.ReceivePacket(out responce);
if (result == PacketCommunicatorReceiveResult.Ok)
{
PortInfo info = ParsePortInfo(responce);
Packet rstPacket = TcpPacketFactory.CreateRstPacketFor(this.options, info.Number);
communicator.SendPacket(rstPacket);
if (scanResults.Add(info))
{
Console.WriteLine(info.ToString());
}
int totalPorts = options.EndPort - options.StartPort;
if (scanResults.Count == totalPorts)
{
break;
}
}
}
}
}
