1#!/usr/bin/env python 2# - 3# SPDX-License-Identifier: BSD-2-Clause 4# 5# Copyright (c) 2020 Alexander V. Chernikov 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# 29 30import argparse 31import logging 32logging.getLogger("scapy").setLevel(logging.CRITICAL) 33import scapy.all as sc 34import socket 35import sys 36import fcntl 37import struct 38 39 40def parse_args(): 41 parser = argparse.ArgumentParser(description='ICMPv6 redirect generator') 42 parser.add_argument('--smac', type=str, required=True, 43 help='eth source mac') 44 parser.add_argument('--dmac', type=str, required=True, 45 help='eth dest mac') 46 parser.add_argument('--sip', type=str, required=True, 47 help='remote router ll source ip') 48 parser.add_argument('--dip', type=str, required=True, 49 help='local router ip') 50 parser.add_argument('--iface', type=str, required=True, 51 help='ifname to send packet to') 52 parser.add_argument('--route', type=str, required=True, 53 help='destination IP to redirect') 54 parser.add_argument('--gw', type=str, required=True, 55 help='redirect GW') 56 return parser.parse_args() 57 58 59def construct_icmp6_redirect(smac, dmac, sip, dip, route_dst, route_gw): 60 e = sc.Ether(src=smac, dst=dmac) 61 l3 = sc.IPv6(src=sip, dst=dip) 62 icmp6 = sc.ICMPv6ND_Redirect(tgt=route_gw, dst=route_dst) 63 return e / l3 / icmp6 64 65 66def send_packet(pkt, iface, feedback=False): 67 if feedback: 68 # Make kernel receive the packet as well 69 BIOCFEEDBACK = 0x8004427c 70 socket = sc.conf.L2socket(iface=args.iface) 71 fcntl.ioctl(socket.ins, BIOCFEEDBACK, struct.pack('I', 1)) 72 sc.sendp(pkt, socket=socket, verbose=True) 73 else: 74 sc.sendp(pkt, iface=iface, verbose=False) 75 76 77def main(): 78 args = parse_args() 79 pkt = construct_icmp6_redirect(args.smac, args.dmac, args.sip, args.dip, 80 args.route, args.gw) 81 send_packet(pkt, args.iface) 82 83 84if __name__ == '__main__': 85 main() 86