sqlmap/lib/request/dns.py
2012-04-04 13:24:58 +00:00

138 lines
3.7 KiB
Python

#!/usr/bin/env python
"""
$Id$
Copyright (c) 2006-2012 sqlmap developers (http://www.sqlmap.org/)
See the file 'doc/COPYING' for copying permission
"""
import os
import re
import socket
import threading
import time
class DNSQuery:
"""
Used for making fake DNS resolution responses based on received
raw request
Reference(s):
http://code.activestate.com/recipes/491264-mini-fake-dns-server/
https://code.google.com/p/marlon-tools/source/browse/tools/dnsproxy/dnsproxy.py
"""
def __init__(self, raw):
self._raw = raw
self._query = ""
type_ = (ord(raw[2]) >> 3) & 15 # Opcode bits
if type_ == 0: # Standard query
i = 12
j = ord(raw[i])
while j != 0:
self._query += raw[i+1:i+j+1] + '.'
i = i + j + 1
j = ord(raw[i])
def response(self, resolution):
"""
Crafts raw DNS resolution response packet
"""
retVal = ""
if self._query:
retVal += self._raw[:2] + "\x81\x80"
retVal += self._raw[4:6] + self._raw[4:6] + "\x00\x00\x00\x00" # Questions and Answers Counts
retVal += self._raw[12:] # Original Domain Name Question
retVal += "\xc0\x0c" # Pointer to domain name
retVal += "\x00\x01\x00\x01\x00\x00\x00\x3c\x00\x04" # Response type, ttl and resource data length -> 4 bytes
retVal += "".join(chr(int(_)) for _ in resolution.split('.')) # 4 bytes of IP
return retVal
class DNSServer:
def __init__(self):
self._requests = []
self._lock = threading.Lock()
self._socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
self._socket.bind(("", 53))
self._running = False
def pop(self, prefix=None, suffix=None):
"""
Returns received DNS resolution request (if any) that has given
prefix/suffix combination (e.g. prefix.<query result>.suffix.domain)
"""
retVal = None
with self._lock:
for _ in self._requests:
if prefix is None and suffix is None or re.search("%s\..+\.%s" % (prefix, suffix), _, re.I):
retVal = _
self._requests.remove(_)
break
return retVal
def run(self):
"""
Runs a DNSServer instance as a daemon thread (killed by program exit)
"""
def _():
try:
self._running = True
while True:
data, addr = self._socket.recvfrom(1024)
_ = DNSQuery(data)
self._socket.sendto(_.response("127.0.0.1"), addr)
with self._lock:
self._requests.append(_._query)
except KeyboardInterrupt:
raise
finally:
self._running = False
thread = threading.Thread(target=_)
thread.daemon = True
thread.start()
if __name__ == "__main__":
server = None
try:
server = DNSServer()
server.run()
while server._running:
while True:
_ = server.pop()
if _ is None:
break
else:
print "[i] %s" % _
time.sleep(1)
except socket.error, ex:
if 'Permission' in str(ex):
print "[x] Please run with sudo/Administrator privileges"
else:
raise
except KeyboardInterrupt:
os._exit(0)
finally:
if server:
server._running = False