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- #! /usr/bin/env python
-
- ########################################
- #
- # wifitap.py --- WiFi injection tool through tun/tap device
- #
- # Copyright (C) 2005 Cedric Blancher <sid@rstack.org>
- #
- # This program is free software; you can redistribute it and/or modify it
- # under the terms of the GNU General Public License version 2 as
- # published by the Free Software Foundation; version 2.
- #
- # This program is distributed in the hope that it will be useful, but
- # WITHOUT ANY WARRANTY; without even the implied warranty of
- # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- # General Public License for more details.
- #
- #########################################
-
- import os,sys,getopt,struct,re,string
-
- # Import Psyco if available to speed up execution
- try:
- import psyco
- psyco.full()
- except ImportError:
- print "Psyco optimizer not installed, running anyway..."
- pass
-
- from socket import *
- from fcntl import ioctl
- from select import select
- from scapy import Raw,Ether,PrismHeader,Dot11,Dot11WEP,LLC,SNAP,sendp,conf
-
- TUNSETIFF = 0x400454ca
- IFF_TAP = 0x0002
- TUNMODE = IFF_TAP
-
- IN_IFACE = "ath0"
- OUT_IFACE = "ath0raw"
- HAS_PRISM = 1
- WEP = 0
- KEYID = 0
- DEBUG = 0
- VERB = 0
- BSSID = ""
- UBSSID = ""
- WEPKEY = ""
-
-
- def usage(status=0):
- print "Usage: wifitap -b <BSSID> [-o <iface>] [-i <iface> [-p]] [-w <WEP key>"
- print " [-k <key id>]] [-d [-v]] [-h]"
- print " -b <BSSID> specify BSSID for injection"
- print " -o <iface> specify interface for injection (default: ath0raw)"
- print " -i <iface> specify interface for listening (default: ath0)"
- print " -p listening interface does not provide Prism Headers"
- print " -w <key> WEP mode and key"
- print " -k <key id> WEP key id (default: 0)"
- print " -d activate debug"
- print " -v verbose debugging"
- print " -h this so helpful output"
- sys.exit(status)
-
- opts = getopt.getopt(sys.argv[1:],"b:o:i:w:k:pdvh")
-
- for opt,optarg in opts[0]:
- if opt == "-b":
- UBSSID = optarg
- elif opt == "-o":
- OUT_IFACE = optarg
- elif opt == "-i":
- IN_IFACE = optarg
- elif opt == "-p":
- HAS_PRISM = 0
- elif opt == "-w":
- WEP += 1
- WEPKEY = optarg
- elif opt == "-k":
- KEYID = int(optarg)
- elif opt == "-d":
- DEBUG += 1
- elif opt == "-v":
- VERB += 1
- elif opt == "-h":
- usage()
-
- if not UBSSID:
- print "\nError: BSSID not defined\n"
- usage()
-
- # Match and parse BSSID
- if re.match('^([0-9a-fA-F]{2}:){5}[0-9a-fA-F]{2}$', UBSSID):
- for i in range(17):
- BSSID += UBSSID[i].lower()
- else:
- print "\nError: Wrong format for BSSID\n"
- usage ()
-
- if HAS_PRISM:
- print "IN_IFACE: %s (Prism headers in capture)" % IN_IFACE
- else:
- print "IN_IFACE: %s (no Prism headers in capture)" % IN_IFACE
- print "OUT_IFACE: %s" % OUT_IFACE
- print "BSSID: %s" % BSSID
-
- if WEP:
- # Match and parse WEP key
- tmp_key = ""
- if re.match('^([0-9a-fA-F]{2}){5}$', WEPKEY) or re.match ('^([0-9a-fA-F]{2}){13}$', WEPKEY):
- tmp_key = WEPKEY
- elif re.match('^([0-9a-fA-F]{2}[:]){4}[0-9a-fA-F]{2}$', WEPKEY) or re.match('^([0-9a-fA-F]{2}[:]){12}[0-9a-fA-F]{2}$', WEPKEY):
- tmp_key = re.sub(':', '', WEPKEY)
- elif re.match ('^([0-9a-fA-F]{4}[-]){2}[0-9a-fA-F]{2}$', WEPKEY) or re.match ('^([0-9a-fA-F]{4}[-]){6}[0-9a-fA-F]{2}$', WEPKEY):
- tmp_key = re.sub('-', '', WEPKEY)
- else:
- print "\nError : Wrong format for WEP key\n"
- usage()
- g = lambda x: chr(int(tmp_key[::2][x],16)*16+int(tmp_key[1::2][x],16))
- for i in range(len(tmp_key)/2):
- conf.wepkey += g(i)
- print "WEP key: %s (%dbits)" % (WEPKEY, len(tmp_key)*4)
- if KEYID > 3 or KEYID < 0:
- print "Key id: %s (defaulted to 0 due to wrong -k argument)" % KEYID
- KEYID = 0
- else:
- print "Key id: %s" % KEYID
- else:
- if KEYID != 0:
- print "WEP not activated, key id ignored"
-
- if not DEBUG:
- if VERB:
- print "DEBUG not activated, verbosity ignored"
- else:
- print "DEBUG activated"
- if VERB:
- print "Verbose debugging"
-
- conf.iface = OUT_IFACE
-
- # Here we put a BPF filter so only 802.11 Data/to-DS frames are captured
- # We need to know if PrismHeaders are present so we can shift lookup index
- if HAS_PRISM:
- s = conf.L2listen(iface = IN_IFACE,
- filter = "link[144]&0xc == 8 and link[145]&0xf == 1")
- else:
- s = conf.L2listen(iface = IN_IFACE,
- filter = "link[0]&0xc == 8 and link[1]&0xf == 1")
-
- # Open /dev/net/tun in TAP (ether) mode
- f = os.open("/dev/net/tun", os.O_RDWR)
- ifs = ioctl(f, TUNSETIFF, struct.pack("16sH", "wj%d", TUNMODE))
- ifname = ifs[:16].strip("\x00")
- print "Interface %s created. Configure it and use it" % ifname
-
-
- try:
- while 1:
- r = select([f,s],[],[])[0][0]
-
- # frame from /dev/net/tun
- if r == f:
-
- # tuntap frame max. size is 1522 (ethernet, see RFC3580) + 4
- buf = os.read(f,1526)
- eth_rcvd_frame=Ether(buf[4:])
-
- if DEBUG:
- os.write(1,"Received from %s\n" % ifname)
- if VERB:
- os.write(1,"%s\n" % eth_rcvd_frame.summary())
-
- # Prepare Dot11 frame for injection
- dot11_sent_frame = Dot11(type = "Data",
- FCfield = "from-DS",
- addr1 = eth_rcvd_frame.getlayer(Ether).dst,
- addr2 = BSSID,
- addr3 = eth_rcvd_frame.getlayer(Ether).src)
- if WEP:
- dot11_sent_frame.FCfield |= 0x40
- dot11_sent_frame /= Dot11WEP(iv = "111",
- keyid = KEYID)
- dot11_sent_frame /= LLC(ctrl = 3)/SNAP()/eth_rcvd_frame.getlayer(Ether).payload
-
- if DEBUG:
- os.write(1,"Sending from-DS to %s\n" % OUT_IFACE)
- if VERB:
- os.write(1,"%s\n" % dot11_sent_frame.summary())
-
- # Frame injection :
- sendp(dot11_sent_frame,verbose=0) # Send from-DS frame
-
- # Frame from WiFi network
- else:
-
- # 802.11 maximum frame size is 2346 bytes (cf. RFC3580)
- # However, WiFi interfaces are always MTUed to 1500
- dot11_rcvd_frame = s.recv(2346)
-
- # WEP handling is automagicly done by Scapy if conf.wepkey is set
- # Nothing to do to decrypt (although not yet tested)
- # WEP frames have Dot11WEP layer, others don't
-
- if DEBUG:
- if dot11_rcvd_frame.haslayer(Dot11WEP): # WEP frame
- os.write(1,"Received WEP from %s\n" % IN_IFACE)
- else: # Cleartext frame
- os.write(1,"Received from %s\n" % IN_IFACE)
- if VERB:
- os.write(1,"%s\n" % dot11_rcvd_frame.summary())
-
- # if dot11_frame.getlayer(Dot11).FCfield & 1: # Frame is to-DS
- # For now, we only take care of to-DS frames...
-
- if dot11_rcvd_frame.getlayer(Dot11).addr1 != BSSID:
- continue
-
- # One day, we'll try to take care of AP to DS trafic (cf. TODO)
- # else: # Frame is from-DS
- # if dot11_frame.getlayer(Dot11).addr2 != BSSID:
- # continue
- # eth_frame = Ether(dst=dot11_frame.getlayer(Dot11).addr1,
- # src=dot11_frame.getlayer(Dot11).addr3)
-
- if dot11_rcvd_frame.haslayer(SNAP):
- eth_sent_frame = Ether(dst=dot11_rcvd_frame.getlayer(Dot11).addr3,
- src=dot11_rcvd_frame.getlayer(Dot11).addr2)
- eth_sent_frame.payload = dot11_rcvd_frame.getlayer(SNAP).payload
- eth_sent_frame.type = dot11_rcvd_frame.getlayer(SNAP).code
-
- if DEBUG:
- os.write(1, "Sending to %s\n" % ifname)
- if VERB:
- os.write(1, "%s\n" % eth_sent_frame.summary())
-
- # Add Tun/Tap header to frame, convert to string and send
- buf = "\x00\x00" + struct.pack("!H",eth_sent_frame.type) + str(eth_sent_frame)
- os.write(f, buf)
-
- # Program killed
- except KeyboardInterrupt:
- print "Stopped by user."
-
- s.close()
- os.close(f)
-
- sys.exit()
-