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