private void bSend_Click(object sender, RoutedEventArgs e)
{
cs.SendMessage(tbTargetUsername.Text, tbMessage.Text);
}
private void AcceptClient()
{
srReceiver = new System.IO.BinaryReader(tcpClient.GetStream());
swSender = new System.IO.BinaryWriter(tcpClient.GetStream());
byte[] answer;
byte[] response;
Int32 length;
// lese laenge von pub key von client
length = srReceiver.ReadInt32();
// empfange client pub key
response = new byte[length];
response = srReceiver.ReadBytes(length);
string clientPubKey = Converter.fromByteArrayToString(response);
Encryption clientEncryption = new Encryption(clientPubKey);
// sende mit client pub key verschlüsselt rij key + iv
answer = clientEncryption.EncryptRSA(serverEncryption.getRijKey());
sendMessage(answer);
answer = clientEncryption.EncryptRSA(serverEncryption.getRijIV());
sendMessage(answer);
// empfange chatmessage objekt mit usernamen signature und message
length = srReceiver.ReadInt32();
response = new byte[length];
response = srReceiver.ReadBytes(length);
Chatmessage message = (Chatmessage)Converter.fromByteArrayToObject(serverEncryption.DecryptRijndael(response));
int pos = 0;
if (message.Signature != _acceptedSignature)
{
pos = -1;
}
currUser = message.Transmitter;
if (currUser != "")
{
Chatmessage serverResponse = new Chatmessage();
serverResponse.Transmitter = "Administrator";
serverResponse.Receiver = currUser;
if (pos == -1)
{
serverResponse.Message = "0|Wrong Client.";
byte[] msg = serverEncryption.EncryptRijndael(Converter.fromObjectToByteArray(serverResponse));
sendMessage(msg);
CloseConnection();
return;
}
else if (ChatServer.userInfos.ContainsKey(currUser) == true)
{
serverResponse.Message = "0|This username already exists.";
byte[] msg = serverEncryption.EncryptRijndael(Converter.fromObjectToByteArray(serverResponse));
sendMessage(msg);
CloseConnection();
return;
}
else if (currUser == "Administrator")
{
serverResponse.Message = "0|This username is reserved.";
byte[] msg = serverEncryption.EncryptRijndael(Converter.fromObjectToByteArray(serverResponse));
sendMessage(msg);
CloseConnection();
return;
}
else
{
serverResponse.Message = "1|Connected Successfully";
byte[] msg = serverEncryption.EncryptRijndael(Converter.fromObjectToByteArray(serverResponse));
sendMessage(msg);
// send actual user list
MemoryStream stream = new MemoryStream();
BinaryFormatter bf = new BinaryFormatter();
bf.Serialize(stream, ChatServer.users);
msg = stream.ToArray();
sendMessage(msg);
// add new user
ChatServer.AddUser(tcpClient, currUser, serverEncryption, message.OperatingSystem);
}
}
else
{
CloseConnection();
return;
}
try
{
while ((length = Convert.ToInt32(srReceiver.ReadInt32())) != 0)
{
response = new byte[length];
response = srReceiver.ReadBytes(length);
var rawResponse = Converter.fromByteArrayToObject(serverEncryption.DecryptRijndael(response));
Chatmessage chatResponse = (Chatmessage)rawResponse;
switch (chatResponse.MessageType)
{
case Chatmessage.MESSAGE_TYPE_DISCONNECT:
// client wants do disconnect
ChatServer.RemoveUser(currUser);
break;
case Chatmessage.MESSAGE_TYPE_USER_INFO:
// send user info of a user to client
ChatServer.SendMessage(currUser, chatResponse.Message, chatResponse.Receiver, Chatmessage.MESSAGE_TYPE_USER_INFO);
break;
case Chatmessage.MESSAGE_TYPE_MESSAGE:
default:
// normal chat message or default behaviour
if (chatResponse.Message.Length > 0)
{
ChatServer.SendMessage(currUser, chatResponse.Message, chatResponse.Receiver, Chatmessage.MESSAGE_TYPE_MESSAGE);
}
else
{
ChatServer.RemoveUser(currUser);
}
break;
}
}
}
catch
{
ChatServer.RemoveUser(currUser);
}
}