非常简单的DNS信息泄漏检测

using System;

using System.Collections.Generic;

using System.Text;

using System.Text.RegularExpressions;

using System.Collections;

using System.IO;

using System.Net.Sockets;

class Program

    {

         static void Main(string[] args)

        {

            string domain = args[0];

            Whois wis = new Whois();

            string result = wis.LookUp(domain);

            Regex reg = new Regex("name\\sserver:(.*)", RegexOptions.IgnoreCase);

            MatchCollection mcs = reg.Matches(result);

            #region 轻量的DNS协议包

            string name = domain.Substring(0, domain.LastIndexOf("."));

            string suffix = domain.Substring(domain.LastIndexOf(".") + 1);

            byte[] namedata = System.Text.ASCIIEncoding.ASCII.GetBytes(name);

            byte[] suffixdata = System.Text.ASCIIEncoding.ASCII.GetBytes(suffix);

            int totallen = 14 + namedata.Length + suffixdata.Length + 7;

            byte[] dnslisarray = new byte[totallen];

            dnslisarray[1] = 0x00;

            dnslisarray[2] = 0x01;

            dnslisarray[5] = 0x01;

            dnslisarray[12] = (byte)(namedata.Length);

            namedata.CopyTo(dnslisarray, 13);

           dnslisarray[13 + namedata.Length] = (byte)suffixdata.Length;

            suffixdata.CopyTo(dnslisarray, 14 + namedata.Length);

            dnslisarray[14 + namedata.Length + suffixdata.Length + 2] = 0xFC;

            dnslisarray[14 + namedata.Length + suffixdata.Length + 4] = 0x01;

            dnslisarray[14 + namedata.Length + suffixdata.Length + 5] = 0x4D;

            dnslisarray[14 + namedata.Length + suffixdata.Length + 6] = 0x53;

            #endregion

            bool ishavevul = false;

            foreach (Match item in mcs)

            {

                if (ishavevul) break ;

                System.Net.Sockets.TcpClient t = new System.Net.Sockets.TcpClient();

                Console.Write("checking dns " + item.Groups[1].Value.Trim());

                t.Connect(item.Groups[1].Value.Trim(), 53);

                t.Client.Send(new byte[] { 0x0, (byte)totallen });

                byte[] buf = new byte[1024];

                t.Client.Send(dnslisarray);

                buf = new byte[16];

                int len = t.Client.Receive(buf);

                t.Close();

                if (buf.Length > 8 && buf[9] > 0)

                {

                    ishavevul = true;

                    Console.Write("\t find more than " + buf[9] + " answers\r\n");

                }

                else

                {

                    Console.Write("\t refuse list\r\n");

                }

            }

            if (!ishavevul)

            {

                Console.WriteLine( args[0] + " is safe");

            }

            else

            {

                Console.WriteLine( args[0] + " is not safe");

            }

         }

    }

补充：综合编程 , 安全编程 ,