private Package ProcessMessage(Package pck)
{
// Console.WriteLine("#Get Message Client: ");
// pck.Print();
Package response = new Package();
RSA certRSA = new RSA(certificateKey);
string[] respCertf = certRSA.decrypt(pck.GetHeader("Certificate")).Split(';');
BigInteger n = BigInteger.Parse(respCertf[2]);
BigInteger e = BigInteger.Parse(respCertf[3]);
int idUser = GetUserByPublicKey(n, e);
switch (pck.GetHeader("Command"))
{
case "Connect":
UserData user = new UserData(n, e, pck.GetHeader("Username"));
users.Add(user);
response.SetHeader("Certificate", certificate);
break;
case "Disconnect":
users.RemoveAt(idUser);
break;
case "DES":
string desEnc = pck.GetHeader("DES Key");
users[idUser].desKey = rsa.decrypt(desEnc);
RSA resRSA = new RSA(users[idUser].key);
response.SetHeader("DES Key", resRSA.encrypt(ecbKey));
break;
case "Message":
Message msg = new Message(users[idUser], ECB.decrypt(pck.GetContent(), users[idUser].desKey));
bufferMessage.Add(msg);
break;
case "New Message":
string lastIndex = ECB.decrypt(pck.GetContent(), users[idUser].desKey);
int index = int.Parse(lastIndex);
if (index < bufferMessage.Count)
{
response.SetContent(bufferMessage[index].user.username + " = " + bufferMessage[index].message);
}
break;
}
if (response.GetContent() != "")
{
response.SetContent(ECB.encrypt(response.GetContent(), ecbKey));
}
return(response);
}
private Package SendCommand(Package pck, int port)
{
TcpClient client = new TcpClient();
IPEndPoint serverEndPoint = new IPEndPoint(IPAddress.Parse("127.0.0.1"), port);
client.Connect(serverEndPoint);
NetworkStream clientStream = client.GetStream();
ASCIIEncoding encoder = new ASCIIEncoding();
if (pck.GetContent() != "")
{
pck.SetContent(ECB.encrypt(pck.GetContent(), ecbKey));
}
String s = pck.GetString();
byte[] buffer = encoder.GetBytes(s);
clientStream.Write(buffer, 0, buffer.Length);
clientStream.Flush();
byte[] bufferResponse = new byte[4096];
clientStream.Read(bufferResponse, 0, 4096);
String response = encoder.GetString(bufferResponse).Replace("\0", "");
client.Close();
Package resp = new Package();
resp.SetByString(response);
//Console.WriteLine("#Response From Server: ");
//resp.Print();
if (port == 1234 && resp.GetContent() != "")
{
resp.SetContent(ECB.decrypt(resp.GetContent(), publicDes));
}
return(resp);
}
