#!/usr/bin/env python # coding: utf-8 # Build By LandGrey import time import struct try: import SocketServer except: import socketserver as SocketServer def current_time(): return time.strftime('[%Y.%m.%d %H:%M:%S]', time.localtime()) class SinDNSQuery: def __init__(self, data): i = 1 self.name = '' while True: try: d = ord(data[i]) except: d = data[i] if d == 0: break if d < 32: self.name += '.' else: self.name += chr(d) i += 1 self.querybytes = data[0:i + 1] self.type, self.classify = struct.unpack('>HH', data[i + 1:i + 5]) self.len = i + 5 def getbytes(self): return self.querybytes + struct.pack('>HH', self.type, self.classify) class SinDNSAnswer: def __init__(self, ip): self.type = 1 self.classify = 1 self.name = 49164 self.datalength = 4 self.timetolive = 190 self.ip = ip def getbytes(self): res = struct.pack('>HHHLH', self.name, self.type, self.classify, self.timetolive, self.datalength) s = self.ip.split('.') res += struct.pack('BBBB', int(s[0]), int(s[1]), int(s[2]), int(s[3])) return res class SinDNSFrame: def __init__(self, data): (self.id, self.flags, self.quests, self.answers, self.author, self.addition) = struct.unpack('>HHHHHH', data[0:12]) self.query = SinDNSQuery(data[12:]) def getname(self): return self.query.name def setip(self, ip): self.answer = SinDNSAnswer(ip) self.answers = 1 self.flags = 33152 def getbytes(self): res = struct.pack('>HHHHHH', self.id, self.flags, self.quests, self.answers, self.author, self.addition) res = res + self.query.getbytes() if self.answers != 0: res += self.answer.getbytes() return res class DnsRequestHandler(SocketServer.BaseRequestHandler): def handle(self): global ip_address data = self.request[0].strip() dns = SinDNSFrame(data) conn = self.request[1] query_name = dns.getname() # A record if dns.query.type == 1: response = ip_address if query_name.endswith(dns_domain) else None if response: dns.setip(response) log_format = {'client_ip': self.client_address[0], 'client_port': self.client_address[1], 'query': query_name, 'record-type': 'A', 'response': response} conn.sendto(dns.getbytes(), self.client_address) print('{} {}'.format(current_time(), log_format)) else: dns.setip(default_ip) conn.sendto(dns.getbytes(), self.client_address) # AAAA record elif dns.query.type == 28: response = ip_address if query_name.endswith(dns_domain) else None if response: dns.setip(response) conn.sendto(dns.getbytes(), self.client_address) log_format = {'client_ip': self.client_address[0], 'client_port': self.client_address[1], 'query': query_name, 'record-type': 'AAAA', 'response': response} print('{} {}'.format(current_time(), log_format)) else: dns.setip(default_ip) conn.sendto(dns.getbytes(), self.client_address) else: dns.setip(default_ip) conn.sendto(dns.getbytes(), self.client_address) class SimpleDnsServer: def __init__(self, port=53): self.port = port def start(self): host, port = "0.0.0.0", self.port dns_udp_server = SocketServer.UDPServer((host, port), DnsRequestHandler) dns_udp_server.serve_forever() if __name__ == "__main__": dns_domain = 'test.com' ip_address = '2.2.2.2' default_ip = '192.168.1.1' dns_server = SimpleDnsServer() print("{} Dnslog server start".format(current_time())) try: dns_server.start() except KeyboardInterrupt: print('{} User quit.'.format(current_time()))