xref: /freebsd/tests/sys/netinet6/redirect.py (revision e17f5b1d) 
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# $FreeBSD$
29#
30
31import argparse
32import scapy.all as sc
33import socket
34import sys
35import fcntl
36import struct
37
38
39def parse_args():
40    parser = argparse.ArgumentParser(description='ICMPv6 redirect generator')
41    parser.add_argument('--smac', type=str, required=True,
42                        help='eth source mac')
43    parser.add_argument('--dmac', type=str, required=True,
44                        help='eth dest mac')
45    parser.add_argument('--sip', type=str, required=True,
46                        help='remote router ll source ip')
47    parser.add_argument('--dip', type=str, required=True,
48                        help='local router ip')
49    parser.add_argument('--iface', type=str, required=True,
50                        help='ifname to send packet to')
51    parser.add_argument('--route', type=str, required=True,
52                        help='destination IP to redirect')
53    parser.add_argument('--gw', type=str, required=True,
54                        help='redirect GW')
55    return parser.parse_args()
56
57
58def construct_icmp6_redirect(smac, dmac, sip, dip, route_dst, route_gw):
59    e = sc.Ether(src=smac, dst=dmac)
60    l3 = sc.IPv6(src=sip, dst=dip)
61    icmp6 = sc.ICMPv6ND_Redirect(tgt=route_gw, dst=route_dst)
62    return e / l3 / icmp6
63
64
65def send_packet(pkt, iface, feedback=False):
66    if feedback:
67        # Make kernel receive the packet as well
68        BIOCFEEDBACK = 0x8004427c
69        socket = sc.conf.L2socket(iface=args.iface)
70        fcntl.ioctl(socket.ins, BIOCFEEDBACK, struct.pack('I', 1))
71        sc.sendp(pkt, socket=socket, verbose=True)
72    else:
73        sc.sendp(pkt, iface=iface, verbose=False)
74
75
76def main():
77    args = parse_args()
78    pkt = construct_icmp6_redirect(args.smac, args.dmac, args.sip, args.dip,
79                                   args.route, args.gw)
80    send_packet(pkt, args.iface)
81
82
83if __name__ == '__main__':
84    main()
85