1#!/usr/bin/env python 2#- 3# SPDX-License-Identifier: BSD-2-Clause 4# 5# Copyright (c) 2019 Netflix, Inc. 6# 7# Redistribution and use in source and binary forms, with or without 8# modification, are permitted provided that the following conditions 9# are met: 10# 1. Redistributions of source code must retain the above copyright 11# notice, this list of conditions and the following disclaimer. 12# 2. Redistributions in binary form must reproduce the above copyright 13# notice, this list of conditions and the following disclaimer in the 14# documentation and/or other materials provided with the distribution. 15# 16# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26# SUCH DAMAGE. 27# 28# $FreeBSD$ 29# 30 31import argparse 32import scapy.all as sp 33import socket 34import sys 35from sniffer import Sniffer 36from time import sleep 37 38def check_icmp6_error(args, packet): 39 ip6 = packet.getlayer(sp.IPv6) 40 if not ip6: 41 return False 42 oip6 = sp.IPv6(src=args.src[0], dst=args.to[0]) 43 if ip6.dst != oip6.src: 44 return False 45 icmp6 = packet.getlayer(sp.ICMPv6ParamProblem) 46 if not icmp6: 47 return False 48 # ICMP6_PARAMPROB_HEADER 0 49 if icmp6.code != 0: 50 return False 51 # Should we check the payload as well? 52 # We are running in a very isolated environment and nothing else 53 # should trigger an ICMPv6 Param Prob so leave it. 54 #icmp6.display() 55 return True 56 57def main(): 58 parser = argparse.ArgumentParser("frag6.py", 59 description="IPv6 fragementation test tool") 60 parser.add_argument('--sendif', nargs=1, 61 required=True, 62 help='The interface through which the packet will be sent') 63 parser.add_argument('--recvif', nargs=1, 64 required=True, 65 help='The interface on which to check for the packet') 66 parser.add_argument('--src', nargs=1, 67 required=True, 68 help='The source IP address') 69 parser.add_argument('--to', nargs=1, 70 required=True, 71 help='The destination IP address') 72 parser.add_argument('--debug', 73 required=False, action='store_true', 74 help='Enable test debugging') 75 76 args = parser.parse_args() 77 78 79 # Start sniffing on recvif 80 sniffer = Sniffer(args, check_icmp6_error) 81 82 83 ######################################################################## 84 # 85 # 0-byte first fragment. 86 # 87 # A: 0-byte fragment payload not allowed. Discarded. 88 # R: ICMPv6 param prob, paramprob header. 89 # 90 ip6f01 = sp.Ether() / \ 91 sp.IPv6(src=args.src[0], dst=args.to[0]) / \ 92 sp.IPv6ExtHdrFragment(offset=0, m=1, id=4) 93 if args.debug : 94 ip6f01.display() 95 sp.sendp(ip6f01, iface=args.sendif[0], verbose=False) 96 97 sleep(0.10) 98 sniffer.setEnd() 99 sniffer.join() 100 if not sniffer.foundCorrectPacket: 101 sys.exit(1) 102 103 sys.exit(0) 104 105if __name__ == '__main__': 106 main() 107