Why Packet sending send no data (handshake with minecraft server)?

Question

I am trying to make a Minecraft fake client a.k.a Minecraft chatbot in c# using packets. I already tried lots of different ways to acomplish this but no luck.

Everytime I send a packet it sends no data (Using a packetsniffer). Although the packetsniffers says that the total size of the packet is: 190 bytes. and the size is: 17 bytes.

Here is my code:

 static TcpClient client = new TcpClient();
    static void Main(string[] args)
    {
        Console.WriteLine("Start GATHERING INFO.....");

        Console.Write("Write a ip: ");
        IPAddress ip = IPAddress.Parse("192.168.178.11");
        try
        {
            ip = IPAddress.Parse(Console.ReadLine());
        }
        catch
        {
            Console.Write("\nUnknown/Wrong ip entered redirecting to :  127.0.0.1 (AKA Localhost)");
            ip = IPAddress.Parse("192.168.178.11");
        }
        Console.Write("\nWrite a port: ");
        int port = int.Parse(Console.ReadLine());

        Console.WriteLine("Connecting.....");

        try
        {
            client.Connect(ip, port);
            client.NoDelay = false;
            Console.WriteLine("Connection succesfull!");
        }catch
        {
            Console.WriteLine("--== ERROR WHILE TRYING TO CONNECT PLEASE RESTART PROGRAM ==--");
            Console.ReadKey();
            client.Close();
            Main(args);
        }

        Stream stream = client.GetStream();

        Console.Write("Please enter a username: ");
        string usrn = Console.ReadLine();
        Console.Write("\n");

        byte[] data = new byte[3 + usrn.Length*2];
        data[0] = (byte)2;
        data[1] = (byte)29;
        gb(usrn).CopyTo(data, 2);

        stream.Write(data, 0, data.Length);

        Console.ReadKey();

    }

    public static byte[] gb(String str)
    {
        return System.Text.ASCIIEncoding.ASCII.GetBytes(str);
    }

Here is how the packet should look like:

http://www.wiki.vg/Protocol#Handshake_.280x02.29

I'm ignoring server host and server port since the other bots didnt use it. (although they didnt work to :/

Here's what the original client packet holds:

'shows weird goto: https://dl.dropbox.com/u/32828727/packetsocketsminecraft.txt '

timboiscool9 (my username) 192.168.178.1 (server ip)

There's more after that but this is what i need.

I am fairly new to sockets and tcpclients

Answer 1

This is a bit old, but I'll still see if I can help you out.

The Minecraft protocol is quite complicated, and you will not be able to connect to Minecraft servers without implementing the vast majority of it. The protocol details can be found here.

I suggest you consider going a different route. Because of how complex Minecraft is, I'd avoid implementing it yourself. Luckily, I'm a Minecraft enthusiast, and I've done most of the work for you. I suggest you take a look at the Craft.Net library. It contains a full protocol implementation and making a chat bot from it would be trivial. In fact, here's an example chat program using Craft.Net for you to peruse.

Answer 2

I cleaned up your code a bit:

    static void Main(string[] args)
    {
        bool keepTrying = true;
        while (keepTrying)
        {
            Console.Write("Enter server IP Address: ");
            IPAddress ip;
            if(!IPAddress.TryParse(Console.ReadLine(), out ip))
            {
                Console.WriteLine("Invalid ip entered, defaulting to 192.168.178.11");
                ip = IPAddress.Parse("192.168.178.11");
            }

            Console.Write("Enter server port: ");
            Int16 port;
            if(!Int16.TryParse(Console.ReadLine(), out port))
            {
                Console.WriteLine("Invalid port entered, defaulting to 1234");
                port = 1234;
            }

            Console.WriteLine("Connecting.....");

            try
            {
                TcpClient client = new TcpClient();
                client.Connect(new IPEndPoint(ip, port));
                client.NoDelay = false;
                Console.WriteLine("Connection succesfull!");

                List<byte> data = new List<byte>() { 2, 29 };
                Console.Write("Please enter a username: ");
                byte[] userName = ASCIIEncoding.ASCII.GetBytes(Console.ReadLine());
                data.AddRange(userName);

                using (var stream = client.GetStream())
                {
                    stream.Write(data.ToArray(), 0, data.Count);
                    Console.Write("Data sent!");
                }
                keepTrying = false;
            }
            catch
            {
                Console.WriteLine("--== ERROR CONNECTING ==--");
                Console.WriteLine();
            }
        }
    }

As for your original question, we need more information. You say that the packet sniffer shows no data but then you say the data has a size. So are you seeing data or not? Are you sure the server is up? The code I posted works for me, meaning it connects to a server on my local system and sends the bytes.