nameserver.py

   1 #!/usr/bin/python3
   2
   3 import asyncio
   4 import hashlib
   5 import os.path
   6
   7 import dns.message
   8
   9 import sqlite3
  10 con = sqlite3.connect("tokens.sqlite")
  11
  12 with con:
  13     con.execute("CREATE TABLE IF NOT EXISTS token (token   CHAR[32], ip   VARCHAR[40])")
  14
  15
  16 class DnsServerProtocol:
  17     def connection_made(self, transport):
  18         self.transport = transport
  19
  20     def datagram_received(self, data, addr):
  21         # with open(os.path.join('packets', hashlib.sha224(data).hexdigest()), 'wb') as fd:
  22         #     fd.write(data)
  23         message = dns.message.from_wire(data)
  24         for question in message.question:
  25             qname = str(question).split('.')[0]
  26
  27             with con:
  28                 con.execute("INSERT INTO token (token, ip) VALUES (?, ?)", (qname, addr[0]))
  29
  30
  31         response = dns.message.make_response(message)
  32         self.transport.sendto(response.to_wire(), addr)
  33
  34 loop = asyncio.get_event_loop()
  35 print("Starting UDP server")
  36 # One protocol instance will be created to serve all client requests
  37 listen = loop.create_datagram_endpoint(
  38     DnsServerProtocol, local_addr=('fda3:c723:abcd:efe1:5054:ff:fec8:148e', 53))
  39 transport, protocol = loop.run_until_complete(listen)
  40 listen = loop.create_datagram_endpoint(
  41     DnsServerProtocol, local_addr=('10.100.96.17', 53))
  42 transport, protocol = loop.run_until_complete(listen)
  43
  44
  45 try:
  46     loop.run_forever()
  47 except KeyboardInterrupt:
  48     pass
  49
  50 transport.close()
  51 loop.close()