xref: /freebsd/usr.sbin/mld6query/mld6.c (revision 59c8e88e72633afbc47a4ace0d2170d00d51f7dc)
1 /*	$KAME: mld6.c,v 1.15 2003/04/02 11:29:54 suz Exp $	*/
2 
3 /*-
4  * SPDX-License-Identifier: BSD-3-Clause
5  *
6  * Copyright (C) 1998 WIDE Project.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. Neither the name of the project nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include <sys/param.h>
35 #include <sys/uio.h>
36 #include <sys/socket.h>
37 #include <sys/types.h>
38 #include <sys/time.h>
39 #include <ifaddrs.h>
40 #include <unistd.h>
41 #include <signal.h>
42 
43 #include <net/if.h>
44 
45 #include <netinet/in.h>
46 #include <netinet/ip6.h>
47 #include <netinet/icmp6.h>
48 
49 #include  <arpa/inet.h>
50 
51 #include <stdlib.h>
52 #include <stdio.h>
53 #include <string.h>
54 #include <err.h>
55 
56 /* portability with older KAME headers */
57 #ifndef MLD_LISTENER_QUERY
58 #define MLD_LISTENER_QUERY	MLD6_LISTENER_QUERY
59 #define MLD_LISTENER_REPORT	MLD6_LISTENER_REPORT
60 #define MLD_LISTENER_DONE	MLD6_LISTENER_DONE
61 #define MLD_MTRACE_RESP		MLD6_MTRACE_RESP
62 #define MLD_MTRACE		MLD6_MTRACE
63 #define mld_hdr		mld6_hdr
64 #define mld_type	mld6_type
65 #define mld_code	mld6_code
66 #define mld_cksum	mld6_cksum
67 #define mld_maxdelay	mld6_maxdelay
68 #define mld_reserved	mld6_reserved
69 #define mld_addr	mld6_addr
70 #endif
71 #ifndef IP6OPT_ROUTER_ALERT
72 #define IP6OPT_ROUTER_ALERT	IP6OPT_RTALERT
73 #endif
74 
75 struct msghdr m;
76 struct sockaddr_in6 dst;
77 struct mld_hdr mldh;
78 struct in6_addr maddr = IN6ADDR_ANY_INIT, any = IN6ADDR_ANY_INIT;
79 struct ipv6_mreq mreq;
80 u_short ifindex;
81 int s;
82 
83 #define QUERY_RESPONSE_INTERVAL 10000
84 
85 void make_msg(int index, struct in6_addr *addr, u_int type, struct in6_addr *qaddr);
86 void usage(void);
87 void dump(int);
88 void quit(int);
89 
90 int
91 main(int argc, char *argv[])
92 {
93 	int i;
94 	struct icmp6_filter filt;
95 	u_int hlim = 1;
96 	fd_set fdset;
97 	struct itimerval itimer;
98 	u_int type;
99 	int ch;
100 	struct in6_addr *qaddr = &maddr;
101 
102 	type = MLD_LISTENER_QUERY;
103 	while ((ch = getopt(argc, argv, "dgr")) != -1) {
104 		switch (ch) {
105 		case 'd':
106 			if (type != MLD_LISTENER_QUERY) {
107 				printf("Can not specify -d with -r\n");
108 				return 1;
109 			}
110 			type = MLD_LISTENER_DONE;
111 			break;
112 		case 'g':
113 			qaddr = &any;
114 			break;
115 		case 'r':
116 			if (type != MLD_LISTENER_QUERY) {
117 				printf("Can not specify -r with -d\n");
118 				return 1;
119 			}
120 			type = MLD_LISTENER_REPORT;
121 			break;
122 		default:
123 			usage();
124 			/*NOTREACHED*/
125 		}
126 	}
127 
128 	argv += optind;
129 	argc -= optind;
130 
131 	if (argc != 1 && argc != 2)
132 		usage();
133 
134 	ifindex = (u_short)if_nametoindex(argv[0]);
135 	if (ifindex == 0)
136 		usage();
137 	if (argc == 2 && inet_pton(AF_INET6, argv[1], &maddr) != 1)
138 		usage();
139 	if (type != MLD_LISTENER_QUERY && qaddr != &maddr) {
140 		printf("Can not specify -g with -d or -r\n");
141 		return 1;
142 	}
143 
144 	if ((s = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0)
145 		err(1, "socket");
146 
147 	if (setsockopt(s, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &hlim,
148 		       sizeof(hlim)) == -1)
149 		err(1, "setsockopt(IPV6_MULTICAST_HOPS)");
150 
151 	if (IN6_IS_ADDR_UNSPECIFIED(&maddr)) {
152 		if (inet_pton(AF_INET6, "ff02::1", &maddr) != 1)
153 			errx(1, "inet_pton failed");
154 	}
155 
156 	mreq.ipv6mr_multiaddr = maddr;
157 	mreq.ipv6mr_interface = ifindex;
158 	if (setsockopt(s, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq,
159 		       sizeof(mreq)) == -1)
160 		err(1, "setsockopt(IPV6_JOIN_GROUP)");
161 
162 	ICMP6_FILTER_SETBLOCKALL(&filt);
163 	ICMP6_FILTER_SETPASS(ICMP6_MEMBERSHIP_QUERY, &filt);
164 	ICMP6_FILTER_SETPASS(ICMP6_MEMBERSHIP_REPORT, &filt);
165 	ICMP6_FILTER_SETPASS(ICMP6_MEMBERSHIP_REDUCTION, &filt);
166 	if (setsockopt(s, IPPROTO_ICMPV6, ICMP6_FILTER, &filt,
167 			sizeof(filt)) < 0)
168 		err(1, "setsockopt(ICMP6_FILTER)");
169 
170 	make_msg(ifindex, &maddr, type, qaddr);
171 
172 	if (sendmsg(s, &m, 0) < 0)
173 		err(1, "sendmsg");
174 
175 	itimer.it_value.tv_sec =  QUERY_RESPONSE_INTERVAL / 1000;
176 	itimer.it_interval.tv_sec = 0;
177 	itimer.it_interval.tv_usec = 0;
178 	itimer.it_value.tv_usec = 0;
179 
180 	(void)signal(SIGALRM, quit);
181 	(void)setitimer(ITIMER_REAL, &itimer, NULL);
182 
183 	FD_ZERO(&fdset);
184 	if (s >= FD_SETSIZE)
185 		errx(1, "descriptor too big");
186 	for (;;) {
187 		FD_SET(s, &fdset);
188 		if ((i = select(s + 1, &fdset, NULL, NULL, NULL)) < 0)
189 			perror("select");
190 		if (i == 0)
191 			continue;
192 		else
193 			dump(s);
194 	}
195 }
196 
197 void
198 make_msg(int index, struct in6_addr *addr, u_int type, struct in6_addr *qaddr)
199 {
200 	static struct iovec iov[2];
201 	static u_char *cmsgbuf;
202 	int cmsglen, hbhlen = 0;
203 	void *hbhbuf = NULL, *optp = NULL;
204 	int currentlen;
205 	struct in6_pktinfo *pi;
206 	struct cmsghdr *cmsgp;
207 	u_short rtalert_code = htons(IP6OPT_RTALERT_MLD);
208 	struct ifaddrs *ifa, *ifap;
209 	struct in6_addr src;
210 
211 	dst.sin6_len = sizeof(dst);
212 	dst.sin6_family = AF_INET6;
213 	dst.sin6_addr = *addr;
214 	m.msg_name = (caddr_t)&dst;
215 	m.msg_namelen = dst.sin6_len;
216 	iov[0].iov_base = (caddr_t)&mldh;
217 	iov[0].iov_len = sizeof(mldh);
218 	m.msg_iov = iov;
219 	m.msg_iovlen = 1;
220 
221 	bzero(&mldh, sizeof(mldh));
222 	mldh.mld_type = type & 0xff;
223 	mldh.mld_maxdelay = htons(QUERY_RESPONSE_INTERVAL);
224 	mldh.mld_addr = *qaddr;
225 
226 	/* MLD packet should be advertised from linklocal address */
227 	getifaddrs(&ifa);
228 	for (ifap = ifa; ifap; ifap = ifap->ifa_next) {
229 		if (index != if_nametoindex(ifap->ifa_name))
230 			continue;
231 
232 		if (ifap->ifa_addr->sa_family != AF_INET6)
233 			continue;
234 		if (!IN6_IS_ADDR_LINKLOCAL(&((struct sockaddr_in6 *)
235 					    ifap->ifa_addr)->sin6_addr))
236 			continue;
237 		break;
238 	}
239 	if (ifap == NULL)
240 		errx(1, "no linklocal address is available");
241 	memcpy(&src, &((struct sockaddr_in6 *)ifap->ifa_addr)->sin6_addr,
242 	       sizeof(src));
243 	freeifaddrs(ifa);
244 #ifdef __KAME__
245 	/* remove embedded ifindex */
246 	src.s6_addr[2] = src.s6_addr[3] = 0;
247 #endif
248 
249 	if ((hbhlen = inet6_opt_init(NULL, 0)) == -1)
250 		errx(1, "inet6_opt_init(0) failed");
251 	if ((hbhlen = inet6_opt_append(NULL, 0, hbhlen, IP6OPT_ROUTER_ALERT, 2,
252 				       2, NULL)) == -1)
253 		errx(1, "inet6_opt_append(0) failed");
254 	if ((hbhlen = inet6_opt_finish(NULL, 0, hbhlen)) == -1)
255 		errx(1, "inet6_opt_finish(0) failed");
256 	cmsglen = CMSG_SPACE(sizeof(struct in6_pktinfo)) + CMSG_SPACE(hbhlen);
257 
258 	if ((cmsgbuf = malloc(cmsglen)) == NULL)
259 		errx(1, "can't allocate enough memory for cmsg");
260 	cmsgp = (struct cmsghdr *)cmsgbuf;
261 	m.msg_control = (caddr_t)cmsgbuf;
262 	m.msg_controllen = cmsglen;
263 	/* specify the outgoing interface */
264 	cmsgp->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
265 	cmsgp->cmsg_level = IPPROTO_IPV6;
266 	cmsgp->cmsg_type = IPV6_PKTINFO;
267 	pi = (struct in6_pktinfo *)CMSG_DATA(cmsgp);
268 	pi->ipi6_ifindex = index;
269 	memcpy(&pi->ipi6_addr, &src, sizeof(pi->ipi6_addr));
270 	/* specify to insert router alert option in a hop-by-hop opt hdr. */
271 	cmsgp = CMSG_NXTHDR(&m, cmsgp);
272 	cmsgp->cmsg_len = CMSG_LEN(hbhlen);
273 	cmsgp->cmsg_level = IPPROTO_IPV6;
274 	cmsgp->cmsg_type = IPV6_HOPOPTS;
275 	hbhbuf = CMSG_DATA(cmsgp);
276 	if ((currentlen = inet6_opt_init(hbhbuf, hbhlen)) == -1)
277 		errx(1, "inet6_opt_init(len = %d) failed", hbhlen);
278 	if ((currentlen = inet6_opt_append(hbhbuf, hbhlen, currentlen,
279 					   IP6OPT_ROUTER_ALERT, 2,
280 					   2, &optp)) == -1)
281 		errx(1, "inet6_opt_append(currentlen = %d, hbhlen = %d) failed",
282 		     currentlen, hbhlen);
283 	(void)inet6_opt_set_val(optp, 0, &rtalert_code, sizeof(rtalert_code));
284 	if ((currentlen = inet6_opt_finish(hbhbuf, hbhlen, currentlen)) == -1)
285 		errx(1, "inet6_opt_finish(buf) failed");
286 }
287 
288 void
289 dump(int s)
290 {
291 	int i;
292 	struct mld_hdr *mld;
293 	u_char buf[1024];
294 	struct sockaddr_in6 from;
295 	int from_len = sizeof(from);
296 	char ntop_buf[256];
297 
298 	if ((i = recvfrom(s, buf, sizeof(buf), 0,
299 			  (struct sockaddr *)&from,
300 			  &from_len)) < 0)
301 		return;
302 
303 	if (i < sizeof(struct mld_hdr)) {
304 		printf("too short!\n");
305 		return;
306 	}
307 
308 	mld = (struct mld_hdr *)buf;
309 
310 	printf("from %s, ", inet_ntop(AF_INET6, &from.sin6_addr,
311 				      ntop_buf, sizeof(ntop_buf)));
312 
313 	switch (mld->mld_type) {
314 	case ICMP6_MEMBERSHIP_QUERY:
315 		printf("type=Multicast Listener Query, ");
316 		break;
317 	case ICMP6_MEMBERSHIP_REPORT:
318 		printf("type=Multicast Listener Report, ");
319 		break;
320 	case ICMP6_MEMBERSHIP_REDUCTION:
321 		printf("type=Multicast Listener Done, ");
322 		break;
323 	}
324 	printf("addr=%s\n", inet_ntop(AF_INET6, &mld->mld_addr,
325 				    ntop_buf, sizeof(ntop_buf)));
326 
327 	fflush(stdout);
328 }
329 
330 void
331 quit(int signum __unused)
332 {
333 	mreq.ipv6mr_multiaddr = maddr;
334 	mreq.ipv6mr_interface = ifindex;
335 	if (setsockopt(s, IPPROTO_IPV6, IPV6_LEAVE_GROUP, &mreq,
336 		       sizeof(mreq)) == -1)
337 		err(1, "setsockopt(IPV6_LEAVE_GROUP)");
338 
339 	exit(0);
340 }
341 
342 void
343 usage(void)
344 {
345 	(void)fprintf(stderr, "usage: mld6query [-dgr] ifname [addr]\n");
346 	exit(1);
347 }
348