/*
C# Network Programming 
by Richard Blum

Publisher: Sybex 
ISBN: 0782141765
*/
using System;
using System.IO;
using System.Net;
using System.Net.Sockets;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Formatters.Soap;
using System.Security;
using System.Security.Cryptography;
using System.Text;

public class CryptoDataRcvr
{
   private SerialEmployee RecvData(NetworkStream strm)
   {
      MemoryStream memstrm = new MemoryStream();

      byte[] Key = {0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,
                    0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16};
      byte[] IV = {0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,
                   0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16};

      TripleDESCryptoServiceProvider tdes = new TripleDESCryptoServiceProvider();
      CryptoStream csw = new CryptoStream(memstrm, tdes.CreateDecryptor(Key, IV),
                         CryptoStreamMode.Write);

      byte[] data = new byte[2048];
      int recv = strm.Read(data, 0, 4);
      int size = BitConverter.ToInt32(data, 0);
      int offset = 0;
      while(size > 0)
      {
         recv = strm.Read(data, 0, size);
         csw.Write(data, offset, recv);
         offset += recv;
         size -= recv;
      }
      csw.FlushFinalBlock();
      IFormatter formatter = new SoapFormatter();
      memstrm.Position = 0;
      SerialEmployee emp = (SerialEmployee)formatter.Deserialize(memstrm);
      memstrm.Close();
      return emp;
   }      

   public CryptoDataRcvr()
   {
      TcpListener server = new TcpListener(9050);
      server.Start();
      Console.WriteLine("Waiting for a client...");
      TcpClient client = server.AcceptTcpClient();
      NetworkStream strm = client.GetStream();

      SerialEmployee emp1 = RecvData(strm);
      Console.WriteLine("emp1.EmployeeID = {0}", emp1.EmployeeID);
      Console.WriteLine("emp1.LastName = {0}", emp1.LastName);
      Console.WriteLine("emp1.FirstName = {0}", emp1.FirstName);
      Console.WriteLine("emp1.YearsService = {0}", emp1.YearsService);
      Console.WriteLine("emp1.Salary = {0}
", emp1.Salary);

      SerialEmployee emp2 = RecvData(strm);
      Console.WriteLine("emp2.EmployeeID = {0}", emp2.EmployeeID);
      Console.WriteLine("emp2.LastName = {0}", emp2.LastName);
      Console.WriteLine("emp2.FirstName = {0}", emp2.FirstName);
      Console.WriteLine("emp2.YearsService = {0}", emp2.YearsService);
      Console.WriteLine("emp2.Salary = {0}", emp2.Salary);
      strm.Close();
      server.Stop();
   }

   public static void Main()
   {
      CryptoDataRcvr cdr = new CryptoDataRcvr();
   }
}

[Serializable]
public class SerialEmployee
{
   public int EmployeeID;
   public string LastName;
   public string FirstName;
   public int YearsService;
   public double Salary;

   public SerialEmployee()
   {
      EmployeeID = 0;
      LastName = null;
      FirstName = null;
      YearsService = 0;
      Salary = 0.0;
   }
}