public static void MessageTransmissionHandler(Message message)
{
byte[] messageBytes = ChatTwo_Protocol.MessageTransmissionHandler(message);
string sharedSecret;
if (message.Type == ChatTwo_Protocol.MessageType.CreateUser)
{
sharedSecret = ChatTwo_Protocol.DefaultSharedSecret;
}
else if (message.Type == ChatTwo_Protocol.MessageType.Login)
{
ServerSharedSecret = ByteHelper.GetHashString(messageBytes);
sharedSecret = ServerSharedSecret;
}
else if (message.To == ChatTwo_Protocol.ServerReserrvedUserID)
{
sharedSecret = ServerSharedSecret;
}
else
{
int userId = message.To;
sharedSecret = _contacts.Find(x => x.ID == userId).Secret;
// Testing!!!! REMOVE THIS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
sharedSecret = ChatTwo_Protocol.DefaultSharedSecret;
}
messageBytes = ChatTwo_Protocol.AddSignatureAndMac(messageBytes, sharedSecret);
// Fire an OnMessageTransmission event.
PacketTransmissionEventArgs args = new PacketTransmissionEventArgs();
args.Destination = message.Ip;
args.PacketContent = messageBytes;
OnMessageTransmission(args);
}
private static string CreateMac(byte[] messageBytes, string sharedSecret)
{
return(ByteHelper.GetHashString(ByteHelper.ConcatinateArray(ByteHelper.GetHashBytes(messageBytes), Convert.FromBase64String(sharedSecret))));
}
/// <summary>
/// This is a threaded method that keeps looping while _online is true.
/// It will receive UDP messages on the UdpClient's port number and forward them to the OnPacketReceived event.
/// </summary>
public void ReceivePacket() // Threaded looping method.
{
while (_online)
{
try
{
IPEndPoint remoteSender = new IPEndPoint(IPAddress.Any, 0);
byte[] receivedBytes = _client.Receive(ref remoteSender);
if (receivedBytes != null && receivedBytes.Length != 0)
{
if (receivedBytes.Length == ByteHelper.HashByteLength + 2 && receivedBytes[0] == 0xCE && receivedBytes[receivedBytes.Length - 1] == 0xCE)
{
if (_messageSendingControlList.Count != 0)
{
// The received message is a ACK message.
string hash = OpenAck(receivedBytes);
ControlledPacket packet = _messageSendingControlList.Find(x => x.Hash == hash);
if (packet != null)
{
_messageSendingControlList.Remove(packet);
}
}
}
else if (receivedBytes.Length == 1 && receivedBytes[0] == 0xEC)
{
// Fire an OnEtherConnectionReply event.
OnEtherConnectionReply(null);
}
else
{
// Send back an ACK packet.
string hash = ByteHelper.GetHashString(receivedBytes);
byte[] ackBytes = CreateAck(hash);
_client.Send(ackBytes, ackBytes.Length, remoteSender);
// Check if the message is a duplicate.
if (!_messageReceivingControlList.Any(x => x == hash))
{
// Add the message's hash to a list so we don't react on the same message twice.
_messageReceivingControlList.Add(hash);
if (_messageReceivingControlList.Count > 5) // Only keep the latest 5 messages.
{
_messageReceivingControlList.RemoveAt(0);
}
// Fire an OnPacketReceived event.
PacketReceivedEventArgs args = new PacketReceivedEventArgs();
args.Sender = remoteSender;
args.Data = receivedBytes;
OnPacketReceived(args);
}
}
}
}
catch (SocketException ex)
{
if (ex.SocketErrorCode != SocketError.TimedOut)
{
System.Diagnostics.Debug.WriteLine("### " + _threadPacketListener.Name + " has crashed:");
System.Diagnostics.Debug.WriteLine("### " + ex.Message);
System.Diagnostics.Debug.WriteLine("### " + ex.ToString());
break;
}
else
{
continue;
}
}
}
}