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 logging 33logging.getLogger("scapy").setLevel(logging.CRITICAL) 34import scapy.all as sp 35import socket 36import sys 37from sniffer import Sniffer 38from time import sleep 39 40def check_icmp6_error(args, packet): 41 ip6 = packet.getlayer(sp.IPv6) 42 if not ip6: 43 return False 44 oip6 = sp.IPv6(src=args.src[0], dst=args.to[0]) 45 if ip6.dst != oip6.src: 46 return False 47 icmp6 = packet.getlayer(sp.ICMPv6ParamProblem) 48 if not icmp6: 49 return False 50 # ICMP6_PARAMPROB_HEADER 0 51 if icmp6.code != 0: 52 return False 53 # Should we check the payload as well? 54 # We are running in a very isolated environment and nothing else 55 # should trigger an ICMPv6 Param Prob so leave it. 56 #icmp6.display() 57 return True 58 59def check_icmp6_error_2(args, packet): 60 ip6 = packet.getlayer(sp.IPv6) 61 if not ip6: 62 return False 63 oip6 = sp.IPv6(src=args.src[0], dst=args.to[0]) 64 if ip6.dst != oip6.src: 65 return False 66 icmp6 = packet.getlayer(sp.ICMPv6TimeExceeded) 67 if not icmp6: 68 return False 69 # ICMP6_TIME_EXCEED_REASSEMBLY 1 70 if icmp6.code != 1: 71 return False 72 # Should we check the payload as well? 73 # We are running in a very isolated environment and nothing else 74 # should trigger an ICMPv6 Time Exceeded / Frag reassembly so leave it. 75 #icmp6.display() 76 return True 77 78 79def main(): 80 parser = argparse.ArgumentParser("frag6.py", 81 description="IPv6 fragementation test tool") 82 parser.add_argument('--sendif', nargs=1, 83 required=True, 84 help='The interface through which the packet will be sent') 85 parser.add_argument('--recvif', nargs=1, 86 required=True, 87 help='The interface on which to check for the packet') 88 parser.add_argument('--src', nargs=1, 89 required=True, 90 help='The source IP address') 91 parser.add_argument('--to', nargs=1, 92 required=True, 93 help='The destination IP address') 94 parser.add_argument('--debug', 95 required=False, action='store_true', 96 help='Enable test debugging') 97 98 args = parser.parse_args() 99 100 101 # Start sniffing on recvif 102 sniffer = Sniffer(args, check_icmp6_error) 103 sniffer2 = Sniffer(args, check_icmp6_error_2) 104 105 106 ######################################################################## 107 # 108 # A fragment with payload and offset set to add up to >64k when 109 # another frag with offset=0 arrives and has an unfrag part. 110 # This is us checking for all fragments queued already when the 111 # one with off=0 arrives. Note: unless the off=0 has its own problem 112 # it will be queued and off!=0 ones might be expunged with param prob. 113 # 114 # A: Reassembly failure, timeout after 115 # R: ICMPv6 param prob, param header (1st frag) 116 # R: ICMPv6 time exceeded (2nd frag, as off=0) 117 # 118 data = "6" * 15 119 ip6f01 = \ 120 sp.Ether() / \ 121 sp.IPv6(src=args.src[0], dst=args.to[0]) / \ 122 sp.IPv6ExtHdrFragment(offset=0x1ffc, m=0, id=8) / \ 123 sp.UDP(dport=3456, sport=6543) / \ 124 data 125 data = "6" * 8 126 ip6f02 = \ 127 sp.Ether() / \ 128 sp.IPv6(src=args.src[0], dst=args.to[0]) / \ 129 sp.IPv6ExtHdrDestOpt(options = \ 130 sp.PadN(optdata="\x00\x00\x00\x00\x00\x00")) / \ 131 sp.IPv6ExtHdrFragment(offset=0, m=1, id=8) / \ 132 sp.UDP(dport=3456, sport=6543) / \ 133 data 134 if args.debug : 135 ip6f01.display() 136 ip6f02.display() 137 sp.sendp(ip6f01, iface=args.sendif[0], verbose=False) 138 sp.sendp(ip6f02, iface=args.sendif[0], verbose=False) 139 140 sleep(1.00) 141 sniffer.setEnd() 142 sniffer.join() 143 if not sniffer.foundCorrectPacket: 144 sys.exit(1) 145 sleep(3) 146 sniffer2.setEnd() 147 sniffer2.join() 148 if not sniffer2.foundCorrectPacket: 149 sys.exit(1) 150 151 sys.exit(0) 152 153if __name__ == '__main__': 154 main() 155