Steganography 17 - FTP Through a Proxy

using System;
using System.Net;
using System.Net.Sockets;
using System.Threading;

namespace SteganoFTP
{
	public class SessionManager
	{
		private const int FTP_COMMAND_PORT = 42; //21;

		private bool isRunning;
		private Socket mainServerSocket;

		public SessionManager()
		{
			OpenLocalSocket();
			Thread mainServerThread = new Thread(new ThreadStart(Listen));
			mainServerThread.Start();
		}

		private void OpenLocalSocket()
		{
			IPHostEntry localHostEntry = Dns.GetHostEntry(Dns.GetHostName());
			IPEndPoint endPoint = new IPEndPoint(localHostEntry.AddressList[0], FTP_COMMAND_PORT);
			this.mainServerSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
			this.mainServerSocket.Bind(endPoint);

			Console.WriteLine("Waiting on Port {0}", endPoint.Port.ToString());
		}

		private void Listen()
		{
			this.isRunning = true;

			string remoteServerName = System.Configuration.ConfigurationSettings.AppSettings["ftpServerName"];
			int remoteServerPort = int.Parse(System.Configuration.ConfigurationSettings.AppSettings["ftpServerPort"]);
			
			try
			{
				while (this.isRunning)
				{
					// accept for connection
					this.mainServerSocket.Listen(10);
					Socket socketToClient = this.mainServerSocket.Accept();
					CommandChannelSocketSet sockets = new CommandChannelSocketSet(socketToClient, remoteServerName, remoteServerPort);
				}
				this.mainServerSocket.Close();
			}
			catch (SocketException ex)
			{
				Console.WriteLine("Socketfehler: {0}", ex.ToString());
			}
		}
	}
}