Your goal is to connect to port 5842 on vortex.labs.overthewire.org and read in 4 unsigned integers in host byte order. Add these integers together and send back the results to get a username and password for vortex1. This information can be used to log in using SSH. Note: vortex is on an 32bit x86 machine (meaning, a little endian architecture)…

vortex0.cs

using System;
using System.Text;
using System.Net.Sockets;

namespace WG
{
    class Program
    {
        static void Main(string[] args)
        {
            TcpClient client = new TcpClient();

            client.Connect("vortex.labs.overthewire.org", 5842);

            NetworkStream stream = client.GetStream();

            int i = 0;
            uint sum = 0;

            while (i++ < 4)
            {
                byte[] buff = new byte[sizeof(uint)];
                stream.Read(buff, 0, buff.Length);

                // data already comes in little endian, so don't
                // need to check for that
                uint num = BitConverter.ToUInt32(buff, 0);

                sum += num;

            }


            byte[] snd = BitConverter.GetBytes(sum);
            stream.Write(snd, 0, snd.Length);


            byte[] authBytes = new byte[512];
            stream.Read(authBytes, 0, authBytes.Length);
            Console.WriteLine(Encoding.ASCII.GetString(authBytes));

            stream.Close();
            client.Close();
        }
    }
}