xref: /aosp_15_r20/external/ot-br-posix/script/reference-device/send_mld_query.py (revision 4a64e381480ef79f0532b2421e44e6ee336b8e0d) 
1#!/usr/bin/env python3
2#
3#  Copyright (c) 2021, The OpenThread Authors.
4#  All rights reserved.
5#
6#  Redistribution and use in source and binary forms, with or without
7#  modification, are permitted provided that the following conditions are met:
8#  1. Redistributions of source code must retain the above copyright
9#     notice, this list of conditions and the following disclaimer.
10#  2. Redistributions in binary form must reproduce the above copyright
11#     notice, this list of conditions and the following disclaimer in the
12#     documentation and/or other materials provided with the distribution.
13#  3. Neither the name of the copyright holder nor the
14#     names of its contributors may be used to endorse or promote products
15#     derived from this software without specific prior written permission.
16#
17#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
18#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
21#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27#  POSSIBILITY OF SUCH DAMAGE.
28#
29#
30#  This script generates and sends MLD Query message on the given interface.
31#
32#  Multicast Listener Query Message (RFC3810):
33#
34#   0                   1                   2                   3
35#   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
36#  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
37#  |  Type = 130   |      Code     |           Checksum            |
38#  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
39#  |    Maximum Response Code      |           Reserved            |
40#  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
41#  |                                                               |
42#  *                                                               *
43#  |                                                               |
44#  *                       Multicast Address                       *
45#  |                                                               |
46#  *                                                               *
47#  |                                                               |
48#  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
49#  | Resv  |S| QRV |     QQIC      |     Number of Sources (N)     |
50#  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
51#
52#  IPv6 Router Alert option (RFC2711) in a Hop-by-Hop Options header:
53#
54#   0                   1                   2                   3
55#   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
56#  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
57#  |  Next Header  |  Hdr Ext Len  |0 0 0|0 0 1 0 1|0 0 0 0 0 0 1 0|
58#  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
59#  |        Value (2 octets)       |             PadN              |
60#  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
61#
62
63import sys
64import socket
65import syslog
66import struct
67
68ICMP6_TYPE_MLD_QUERY = 130
69IPV6_EXT_HBH_ROUTER_ALERT = 5
70
71def main():
72    interface = sys.argv[1]
73    dst = sys.argv[2]
74
75    log = '====otbr-agent=send_mld_query===  send_mld_query.py started'
76    syslog.syslog(syslog.LOG_ERR, log)
77    print(log)
78
79    log = 'interface %s' % interface
80    syslog.syslog(syslog.LOG_ERR, log)
81    print(log)
82
83    log = 'dst %s' % dst
84    syslog.syslog(syslog.LOG_ERR, log)
85    print(log)
86
87    try:
88        sock = socket.socket(socket.AF_INET6, socket.SOCK_RAW, socket.IPPROTO_ICMPV6)
89
90        # Configure SO_BINDTODEVICE to bind the network interface.
91        sock.setsockopt(socket.SOL_SOCKET, 25, interface.encode('utf-8'))
92        sock.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_MULTICAST_HOPS, 1)
93
94        # Build ICMPv6 MLD Query message header
95        query  = struct.pack("B", ICMP6_TYPE_MLD_QUERY) # Type: 130
96        query += struct.pack("B", 0) # Code
97        query += struct.pack("!H", 0) # Checksum
98
99        # Query Response Interval: 10 seconds (RFC 3810, section 9.3)
100        query += struct.pack("!H", 10000)
101
102        # Reserved field
103        query += struct.pack("!H", 0)
104
105        # Multicast address (unspecified)
106        query += struct.pack("!16s", ''.encode())
107
108        # Querier's Robustness Variable: 2 (RFC 3810, section 9.1)
109        query += struct.pack("B", 2)
110
111        # Querier's Query Interval Code: 125 (RFC 3810, section 9.2)
112        query += struct.pack("B", 125)
113
114        # Number of sources
115        query += struct.pack("!H", 0)
116
117        # Build IPv6 Hop-by-Hop header
118        ext_hdr  = struct.pack("B", socket.getprotobyname('ipv6-icmp'))
119        ext_hdr += struct.pack("B", 0)
120
121        # Include Router Alert option (RFC 2711)
122        ext_hdr += struct.pack("B", IPV6_EXT_HBH_ROUTER_ALERT)
123        ext_hdr += struct.pack("B", 2)  # Length
124        ext_hdr += struct.pack("!H", 0) # MLD message
125
126        # Insert PadN option to keep alignment (2-bytes)
127        ext_hdr += struct.pack("B", 1)
128        ext_hdr += struct.pack("B", 0)
129
130        # Send MLD Query message
131        sock.sendmsg([query], [(socket.IPPROTO_IPV6, socket.IPV6_HOPOPTS, ext_hdr)], 0, (dst, 0, 0))
132
133    except Exception as e:
134        log = '====otbr-agent=send_mld_query=== sendmsg %s' % str(e)
135        syslog.syslog(syslog.LOG_ERR, log)
136        print(log)
137
138    sock.close()
139    log = '====otbr-agent=send_mld_query=== close'
140    syslog.syslog(syslog.LOG_ERR, log)
141    print(log)
142
143if __name__ == '__main__':
144    main()
145