xref: /freebsd/usr.sbin/mld6query/mld6.c (revision c1839039b193b48c8eb7520c75487f0bd4340c3b)
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/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #include <sys/param.h>
38 #include <sys/uio.h>
39 #include <sys/socket.h>
40 #include <sys/types.h>
41 #include <sys/time.h>
42 #include <ifaddrs.h>
43 #include <unistd.h>
44 #include <signal.h>
45 
46 #include <net/if.h>
47 
48 #include <netinet/in.h>
49 #include <netinet/ip6.h>
50 #include <netinet/icmp6.h>
51 
52 #include  <arpa/inet.h>
53 
54 #include <stdlib.h>
55 #include <stdio.h>
56 #include <string.h>
57 #include <err.h>
58 
59 /* portability with older KAME headers */
60 #ifndef MLD_LISTENER_QUERY
61 #define MLD_LISTENER_QUERY	MLD6_LISTENER_QUERY
62 #define MLD_LISTENER_REPORT	MLD6_LISTENER_REPORT
63 #define MLD_LISTENER_DONE	MLD6_LISTENER_DONE
64 #define MLD_MTRACE_RESP		MLD6_MTRACE_RESP
65 #define MLD_MTRACE		MLD6_MTRACE
66 #define mld_hdr		mld6_hdr
67 #define mld_type	mld6_type
68 #define mld_code	mld6_code
69 #define mld_cksum	mld6_cksum
70 #define mld_maxdelay	mld6_maxdelay
71 #define mld_reserved	mld6_reserved
72 #define mld_addr	mld6_addr
73 #endif
74 #ifndef IP6OPT_ROUTER_ALERT
75 #define IP6OPT_ROUTER_ALERT	IP6OPT_RTALERT
76 #endif
77 
78 struct msghdr m;
79 struct sockaddr_in6 dst;
80 struct mld_hdr mldh;
81 struct in6_addr maddr = IN6ADDR_ANY_INIT, any = IN6ADDR_ANY_INIT;
82 struct ipv6_mreq mreq;
83 u_short ifindex;
84 int s;
85 
86 #define QUERY_RESPONSE_INTERVAL 10000
87 
88 void make_msg(int index, struct in6_addr *addr, u_int type, struct in6_addr *qaddr);
89 void usage(void);
90 void dump(int);
91 void quit(int);
92 
93 int
94 main(int argc, char *argv[])
95 {
96 	int i;
97 	struct icmp6_filter filt;
98 	u_int hlim = 1;
99 	fd_set fdset;
100 	struct itimerval itimer;
101 	u_int type;
102 	int ch;
103 	struct in6_addr *qaddr = &maddr;
104 
105 	type = MLD_LISTENER_QUERY;
106 	while ((ch = getopt(argc, argv, "dgr")) != -1) {
107 		switch (ch) {
108 		case 'd':
109 			if (type != MLD_LISTENER_QUERY) {
110 				printf("Can not specify -d with -r\n");
111 				return 1;
112 			}
113 			type = MLD_LISTENER_DONE;
114 			break;
115 		case 'g':
116 			qaddr = &any;
117 			break;
118 		case 'r':
119 			if (type != MLD_LISTENER_QUERY) {
120 				printf("Can not specify -r with -d\n");
121 				return 1;
122 			}
123 			type = MLD_LISTENER_REPORT;
124 			break;
125 		default:
126 			usage();
127 			/*NOTREACHED*/
128 		}
129 	}
130 
131 	argv += optind;
132 	argc -= optind;
133 
134 	if (argc != 1 && argc != 2)
135 		usage();
136 
137 	ifindex = (u_short)if_nametoindex(argv[0]);
138 	if (ifindex == 0)
139 		usage();
140 	if (argc == 2 && inet_pton(AF_INET6, argv[1], &maddr) != 1)
141 		usage();
142 	if (type != MLD_LISTENER_QUERY && qaddr != &maddr) {
143 		printf("Can not specify -g with -d or -r\n");
144 		return 1;
145 	}
146 
147 	if ((s = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0)
148 		err(1, "socket");
149 
150 	if (setsockopt(s, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &hlim,
151 		       sizeof(hlim)) == -1)
152 		err(1, "setsockopt(IPV6_MULTICAST_HOPS)");
153 
154 	if (IN6_IS_ADDR_UNSPECIFIED(&maddr)) {
155 		if (inet_pton(AF_INET6, "ff02::1", &maddr) != 1)
156 			errx(1, "inet_pton failed");
157 	}
158 
159 	mreq.ipv6mr_multiaddr = maddr;
160 	mreq.ipv6mr_interface = ifindex;
161 	if (setsockopt(s, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq,
162 		       sizeof(mreq)) == -1)
163 		err(1, "setsockopt(IPV6_JOIN_GROUP)");
164 
165 	ICMP6_FILTER_SETBLOCKALL(&filt);
166 	ICMP6_FILTER_SETPASS(ICMP6_MEMBERSHIP_QUERY, &filt);
167 	ICMP6_FILTER_SETPASS(ICMP6_MEMBERSHIP_REPORT, &filt);
168 	ICMP6_FILTER_SETPASS(ICMP6_MEMBERSHIP_REDUCTION, &filt);
169 	if (setsockopt(s, IPPROTO_ICMPV6, ICMP6_FILTER, &filt,
170 			sizeof(filt)) < 0)
171 		err(1, "setsockopt(ICMP6_FILTER)");
172 
173 	make_msg(ifindex, &maddr, type, qaddr);
174 
175 	if (sendmsg(s, &m, 0) < 0)
176 		err(1, "sendmsg");
177 
178 	itimer.it_value.tv_sec =  QUERY_RESPONSE_INTERVAL / 1000;
179 	itimer.it_interval.tv_sec = 0;
180 	itimer.it_interval.tv_usec = 0;
181 	itimer.it_value.tv_usec = 0;
182 
183 	(void)signal(SIGALRM, quit);
184 	(void)setitimer(ITIMER_REAL, &itimer, NULL);
185 
186 	FD_ZERO(&fdset);
187 	if (s >= FD_SETSIZE)
188 		errx(1, "descriptor too big");
189 	for (;;) {
190 		FD_SET(s, &fdset);
191 		if ((i = select(s + 1, &fdset, NULL, NULL, NULL)) < 0)
192 			perror("select");
193 		if (i == 0)
194 			continue;
195 		else
196 			dump(s);
197 	}
198 }
199 
200 void
201 make_msg(int index, struct in6_addr *addr, u_int type, struct in6_addr *qaddr)
202 {
203 	static struct iovec iov[2];
204 	static u_char *cmsgbuf;
205 	int cmsglen, hbhlen = 0;
206 	void *hbhbuf = NULL, *optp = NULL;
207 	int currentlen;
208 	struct in6_pktinfo *pi;
209 	struct cmsghdr *cmsgp;
210 	u_short rtalert_code = htons(IP6OPT_RTALERT_MLD);
211 	struct ifaddrs *ifa, *ifap;
212 	struct in6_addr src;
213 
214 	dst.sin6_len = sizeof(dst);
215 	dst.sin6_family = AF_INET6;
216 	dst.sin6_addr = *addr;
217 	m.msg_name = (caddr_t)&dst;
218 	m.msg_namelen = dst.sin6_len;
219 	iov[0].iov_base = (caddr_t)&mldh;
220 	iov[0].iov_len = sizeof(mldh);
221 	m.msg_iov = iov;
222 	m.msg_iovlen = 1;
223 
224 	bzero(&mldh, sizeof(mldh));
225 	mldh.mld_type = type & 0xff;
226 	mldh.mld_maxdelay = htons(QUERY_RESPONSE_INTERVAL);
227 	mldh.mld_addr = *qaddr;
228 
229 	/* MLD packet should be advertised from linklocal address */
230 	getifaddrs(&ifa);
231 	for (ifap = ifa; ifap; ifap = ifap->ifa_next) {
232 		if (index != if_nametoindex(ifap->ifa_name))
233 			continue;
234 
235 		if (ifap->ifa_addr->sa_family != AF_INET6)
236 			continue;
237 		if (!IN6_IS_ADDR_LINKLOCAL(&((struct sockaddr_in6 *)
238 					    ifap->ifa_addr)->sin6_addr))
239 			continue;
240 		break;
241 	}
242 	if (ifap == NULL)
243 		errx(1, "no linklocal address is available");
244 	memcpy(&src, &((struct sockaddr_in6 *)ifap->ifa_addr)->sin6_addr,
245 	       sizeof(src));
246 	freeifaddrs(ifa);
247 #ifdef __KAME__
248 	/* remove embedded ifindex */
249 	src.s6_addr[2] = src.s6_addr[3] = 0;
250 #endif
251 
252 	if ((hbhlen = inet6_opt_init(NULL, 0)) == -1)
253 		errx(1, "inet6_opt_init(0) failed");
254 	if ((hbhlen = inet6_opt_append(NULL, 0, hbhlen, IP6OPT_ROUTER_ALERT, 2,
255 				       2, NULL)) == -1)
256 		errx(1, "inet6_opt_append(0) failed");
257 	if ((hbhlen = inet6_opt_finish(NULL, 0, hbhlen)) == -1)
258 		errx(1, "inet6_opt_finish(0) failed");
259 	cmsglen = CMSG_SPACE(sizeof(struct in6_pktinfo)) + CMSG_SPACE(hbhlen);
260 
261 	if ((cmsgbuf = malloc(cmsglen)) == NULL)
262 		errx(1, "can't allocate enough memory for cmsg");
263 	cmsgp = (struct cmsghdr *)cmsgbuf;
264 	m.msg_control = (caddr_t)cmsgbuf;
265 	m.msg_controllen = cmsglen;
266 	/* specify the outgoing interface */
267 	cmsgp->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
268 	cmsgp->cmsg_level = IPPROTO_IPV6;
269 	cmsgp->cmsg_type = IPV6_PKTINFO;
270 	pi = (struct in6_pktinfo *)CMSG_DATA(cmsgp);
271 	pi->ipi6_ifindex = index;
272 	memcpy(&pi->ipi6_addr, &src, sizeof(pi->ipi6_addr));
273 	/* specify to insert router alert option in a hop-by-hop opt hdr. */
274 	cmsgp = CMSG_NXTHDR(&m, cmsgp);
275 	cmsgp->cmsg_len = CMSG_LEN(hbhlen);
276 	cmsgp->cmsg_level = IPPROTO_IPV6;
277 	cmsgp->cmsg_type = IPV6_HOPOPTS;
278 	hbhbuf = CMSG_DATA(cmsgp);
279 	if ((currentlen = inet6_opt_init(hbhbuf, hbhlen)) == -1)
280 		errx(1, "inet6_opt_init(len = %d) failed", hbhlen);
281 	if ((currentlen = inet6_opt_append(hbhbuf, hbhlen, currentlen,
282 					   IP6OPT_ROUTER_ALERT, 2,
283 					   2, &optp)) == -1)
284 		errx(1, "inet6_opt_append(currentlen = %d, hbhlen = %d) failed",
285 		     currentlen, hbhlen);
286 	(void)inet6_opt_set_val(optp, 0, &rtalert_code, sizeof(rtalert_code));
287 	if ((currentlen = inet6_opt_finish(hbhbuf, hbhlen, currentlen)) == -1)
288 		errx(1, "inet6_opt_finish(buf) failed");
289 }
290 
291 void
292 dump(int s)
293 {
294 	int i;
295 	struct mld_hdr *mld;
296 	u_char buf[1024];
297 	struct sockaddr_in6 from;
298 	int from_len = sizeof(from);
299 	char ntop_buf[256];
300 
301 	if ((i = recvfrom(s, buf, sizeof(buf), 0,
302 			  (struct sockaddr *)&from,
303 			  &from_len)) < 0)
304 		return;
305 
306 	if (i < sizeof(struct mld_hdr)) {
307 		printf("too short!\n");
308 		return;
309 	}
310 
311 	mld = (struct mld_hdr *)buf;
312 
313 	printf("from %s, ", inet_ntop(AF_INET6, &from.sin6_addr,
314 				      ntop_buf, sizeof(ntop_buf)));
315 
316 	switch (mld->mld_type) {
317 	case ICMP6_MEMBERSHIP_QUERY:
318 		printf("type=Multicast Listener Query, ");
319 		break;
320 	case ICMP6_MEMBERSHIP_REPORT:
321 		printf("type=Multicast Listener Report, ");
322 		break;
323 	case ICMP6_MEMBERSHIP_REDUCTION:
324 		printf("type=Multicast Listener Done, ");
325 		break;
326 	}
327 	printf("addr=%s\n", inet_ntop(AF_INET6, &mld->mld_addr,
328 				    ntop_buf, sizeof(ntop_buf)));
329 
330 	fflush(stdout);
331 }
332 
333 void
334 quit(int signum __unused)
335 {
336 	mreq.ipv6mr_multiaddr = maddr;
337 	mreq.ipv6mr_interface = ifindex;
338 	if (setsockopt(s, IPPROTO_IPV6, IPV6_LEAVE_GROUP, &mreq,
339 		       sizeof(mreq)) == -1)
340 		err(1, "setsockopt(IPV6_LEAVE_GROUP)");
341 
342 	exit(0);
343 }
344 
345 void
346 usage(void)
347 {
348 	(void)fprintf(stderr, "usage: mld6query [-dgr] ifname [addr]\n");
349 	exit(1);
350 }
351