xref: /netbsd-src/usr.sbin/mrinfo/mrinfo.c (revision 274254cdae52594c1aa480a736aef78313d15c9c)
1 /*	$NetBSD: mrinfo.c,v 1.26 2007/02/22 01:29:35 hubertf Exp $	*/
2 
3 /*
4  * This tool requests configuration info from a multicast router
5  * and prints the reply (if any).  Invoke it as:
6  *
7  *	mrinfo router-name-or-address
8  *
9  * Written Wed Mar 24 1993 by Van Jacobson (adapted from the
10  * multicast mapper written by Pavel Curtis).
11  *
12  * The lawyers insist we include the following UC copyright notice.
13  * The mapper from which this is derived contained a Xerox copyright
14  * notice which follows the UC one.  Try not to get depressed noting
15  * that the legal gibberish is larger than the program.
16  *
17  * Copyright (c) 1993 Regents of the University of California.
18  * All rights reserved.
19  *
20  * Redistribution and use in source and binary forms, with or without
21  * modification, are permitted provided that the following conditions
22  * are met:
23  * 1. Redistributions of source code must retain the above copyright
24  *    notice, this list of conditions and the following disclaimer.
25  * 2. Redistributions in binary form must reproduce the above copyright
26  *    notice, this list of conditions and the following disclaimer in the
27  *    documentation and/or other materials provided with the distribution.
28  * 3. All advertising materials mentioning features or use of this software
29  *    must display the following acknowledgement:
30  *	This product includes software developed by the Computer Systems
31  *	Engineering Group at Lawrence Berkeley Laboratory.
32  * 4. Neither the name of the University nor of the Laboratory may be used
33  *    to endorse or promote products derived from this software without
34  *    specific prior written permission.
35  *
36  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
37  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
38  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
39  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
40  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
41  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
42  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
43  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
44  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
45  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
46  * SUCH DAMAGE.
47  * ---------------------------------
48  * Copyright (c) 1992, 2001 Xerox Corporation.  All rights reserved.
49  *
50  * Redistribution and use in source and binary forms, with or without modification,
51  * are permitted provided that the following conditions are met:
52  *
53  * Redistributions of source code must retain the above copyright notice,
54  * this list of conditions and the following disclaimer.
55  *
56  * Redistributions in binary form must reproduce the above copyright notice,
57  * this list of conditions and the following disclaimer in the documentation
58  * and/or other materials provided with the distribution.
59 
60  * Neither name of the Xerox, PARC, nor the names of its contributors may be used
61  * to endorse or promote products derived from this software
62  * without specific prior written permission.
63  *
64  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS''
65  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
66  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
67  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE XEROX CORPORATION OR CONTRIBUTORS
68  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
69  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
70  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
71  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
72  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
73  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
74  * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
75  */
76 
77 #include <sys/cdefs.h>
78 #ifndef lint
79 #if 0
80 static char rcsid[] =
81     "@(#) Header: mrinfo.c,v 1.6 93/04/08 15:14:16 van Exp (LBL)";
82 #else
83 __RCSID("$NetBSD: mrinfo.c,v 1.26 2007/02/22 01:29:35 hubertf Exp $");
84 #endif
85 #endif
86 
87 #include <ctype.h>
88 #include <string.h>
89 #include <netdb.h>
90 #include <sys/time.h>
91 #include <poll.h>
92 #include "defs.h"
93 #include <arpa/inet.h>
94 #include <stdarg.h>
95 
96 #define DEFAULT_TIMEOUT	4	/* How long to wait before retrying requests */
97 #define DEFAULT_RETRIES 3	/* How many times to ask each router */
98 
99 u_int32_t	our_addr, target_addr = 0;	/* in NET order */
100 int     debug = 0;
101 int	nflag = 0;
102 int     retries = DEFAULT_RETRIES;
103 int     timeout = DEFAULT_TIMEOUT;
104 int	target_level = 0;
105 vifi_t  numvifs;		/* to keep loader happy */
106 				/* (see COPY_TABLES macro called in kern.c) */
107 
108 char *			inet_name(u_int32_t addr);
109 void			ask(u_int32_t dst);
110 void			ask2(u_int32_t dst);
111 int			get_number(int *var, int deflt, char ***pargv,
112 				   int *pargc);
113 u_int32_t		host_addr(char *name);
114 void			usage(void);
115 
116 /* to shut up -Wstrict-prototypes */
117 int			main(int argc, char *argv[]);
118 /* logit() prototyped in defs.h */
119 
120 
121 char   *
122 inet_name(u_int32_t addr)
123 {
124 	struct hostent *e;
125 	struct in_addr in;
126 
127 	if (addr == 0)
128 		return "local";
129 
130 	if (nflag ||
131 	    (e = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET)) == NULL) {
132 		in.s_addr = addr;
133 		return (inet_ntoa(in));
134 	}
135 	return (e->h_name);
136 }
137 
138 /*
139  * Log errors and other messages to stderr, according to the severity of the
140  * message and the current debug level.  For errors of severity LOG_ERR or
141  * worse, terminate the program.
142  */
143 void
144 logit(int severity, int syserr, const char *format, ...)
145 {
146 	va_list ap;
147 
148 	switch (debug) {
149 	case 0:
150 		if (severity > LOG_WARNING)
151 			return;
152 	case 1:
153 		if (severity > LOG_NOTICE)
154 			return;
155 	case 2:
156 		if (severity > LOG_INFO)
157 			return;
158 	default:
159 		if (severity == LOG_WARNING)
160 			fprintf(stderr, "warning - ");
161 		va_start(ap, format);
162 		vfprintf(stderr, format, ap);
163 		va_end(ap);
164 		if (syserr == 0)
165 			fprintf(stderr, "\n");
166 		else
167 			fprintf(stderr, ": %s\n", strerror(syserr));
168 	}
169 
170 	if (severity <= LOG_ERR)
171 		exit(1);
172 }
173 
174 /*
175  * Send a neighbors-list request.
176  */
177 void
178 ask(u_int32_t dst)
179 {
180 	send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS,
181 			htonl(MROUTED_LEVEL), 0);
182 }
183 
184 void
185 ask2(u_int32_t dst)
186 {
187 	send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS2,
188 			htonl(MROUTED_LEVEL), 0);
189 }
190 
191 /*
192  * Process an incoming neighbor-list message.
193  */
194 void
195 accept_neighbors(u_int32_t src, u_int32_t dst, u_char *p, int datalen,
196 		 u_int32_t level)
197 {
198 	u_char *ep = p + datalen;
199 #define GET_ADDR(a) (a = ((u_int32_t)*p++ << 24), a += ((u_int32_t)*p++ << 16),\
200 		     a += ((u_int32_t)*p++ << 8), a += *p++)
201 
202 	printf("%s (%s):\n", inet_fmt(src), inet_name(src));
203 	while (p < ep) {
204 		u_int32_t laddr;
205 		u_char metric;
206 		u_char thresh;
207 		int ncount;
208 
209 		GET_ADDR(laddr);
210 		laddr = htonl(laddr);
211 		metric = *p++;
212 		thresh = *p++;
213 		ncount = *p++;
214 		while (--ncount >= 0) {
215 			u_int32_t neighbor;
216 			GET_ADDR(neighbor);
217 			neighbor = htonl(neighbor);
218 			printf("  %s -> ", inet_fmt(laddr));
219 			printf("%s (%s) [%d/%d]\n",
220 				inet_fmt(neighbor),
221 			       inet_name(neighbor), metric, thresh);
222 		}
223 	}
224 }
225 
226 void
227 accept_neighbors2(u_int32_t src, u_int32_t dst, u_char *p, int datalen,
228 		  u_int32_t level)
229 {
230 	u_char *ep = p + datalen;
231 	u_int broken_cisco = ((level & 0xffff) == 0x020a); /* 10.2 */
232 	/* well, only possibly_broken_cisco, but that's too long to type. */
233 
234 	printf("%s (%s) [version %d.%d", inet_fmt(src),
235 		inet_name(src), level & 0xff, (level >> 8) & 0xff);
236 	if ((level >> 16) & NF_LEAF)   { printf (",leaf"); }
237 	if ((level >> 16) & NF_PRUNE)  { printf (",prune"); }
238 	if ((level >> 16) & NF_GENID)  { printf (",genid"); }
239 	if ((level >> 16) & NF_MTRACE) { printf (",mtrace"); }
240 	printf ("]:\n");
241 
242 	while (p < ep) {
243 		u_char metric;
244 		u_char thresh;
245 		u_char flags;
246 		int ncount;
247 		u_int32_t laddr = *(u_int32_t*)p;
248 
249 		p += 4;
250 		metric = *p++;
251 		thresh = *p++;
252 		flags = *p++;
253 		ncount = *p++;
254 		if (broken_cisco && ncount == 0)	/* dumb Ciscos */
255 			ncount = 1;
256 		if (broken_cisco && ncount > 15)	/* dumb Ciscos */
257 			ncount = ncount & 0xf;
258 		while (--ncount >= 0 && p < ep) {
259 			u_int32_t neighbor = *(u_int32_t*)p;
260 			p += 4;
261 			printf("  %s -> ", inet_fmt(laddr));
262 			printf("%s (%s) [%d/%d",
263 				inet_fmt(neighbor),
264 				inet_name(neighbor), metric, thresh);
265 			if (flags & DVMRP_NF_TUNNEL)
266 				printf("/tunnel");
267 			if (flags & DVMRP_NF_SRCRT)
268 				printf("/srcrt");
269 			if (flags & DVMRP_NF_PIM)
270 				printf("/pim");
271 			if (flags & DVMRP_NF_QUERIER)
272 				printf("/querier");
273 			if (flags & DVMRP_NF_DISABLED)
274 				printf("/disabled");
275 			if (flags & DVMRP_NF_DOWN)
276 				printf("/down");
277 			if (flags & DVMRP_NF_LEAF)
278 				printf("/leaf");
279 			printf("]\n");
280 		}
281 	}
282 }
283 
284 int
285 get_number(int *var, int deflt, char ***pargv, int *pargc)
286 {
287 	if ((*pargv)[0][2] == '\0') {	/* Get the value from the next
288 					 * argument */
289 		if (*pargc > 1 && isdigit((unsigned char)(*pargv)[1][0])) {
290 			(*pargv)++, (*pargc)--;
291 			*var = atoi((*pargv)[0]);
292 			return 1;
293 		} else if (deflt >= 0) {
294 			*var = deflt;
295 			return 1;
296 		} else
297 			return 0;
298 	} else {		/* Get value from the rest of this argument */
299 		if (isdigit((unsigned char)(*pargv)[0][2])) {
300 			*var = atoi((*pargv)[0] + 2);
301 			return 1;
302 		} else {
303 			return 0;
304 		}
305 	}
306 }
307 
308 void
309 usage(void)
310 {
311 	fprintf(stderr,
312 	    "usage: mrinfo [-n] [-t timeout] [-r retries] [router]\n");
313 	exit(1);
314 }
315 
316 int
317 main(int argc, char *argv[])
318 {
319 	int tries;
320 	int trynew;
321 	struct timeval et;
322 	struct hostent *hp;
323 	struct hostent bogus;
324 	char *host;
325 	int curaddr;
326 
327 	if (geteuid() != 0) {
328 		fprintf(stderr, "mrinfo: must be root\n");
329 		exit(1);
330 	}
331 	init_igmp();
332 	if (setuid(getuid()) == -1)
333 		logit(LOG_ERR, errno, "setuid");
334 
335 	setlinebuf(stderr);
336 
337 	argv++, argc--;
338 	while (argc > 0 && argv[0][0] == '-') {
339 		switch (argv[0][1]) {
340 		case 'd':
341 			if (!get_number(&debug, DEFAULT_DEBUG, &argv, &argc))
342 				usage();
343 			break;
344 		case 'n':
345 			++nflag;
346 			break;
347 		case 'r':
348 			if (!get_number(&retries, -1, &argv, &argc))
349 				usage();
350 			break;
351 		case 't':
352 			if (!get_number(&timeout, -1, &argv, &argc))
353 				usage();
354 			break;
355 		default:
356 			usage();
357 		}
358 		argv++, argc--;
359 	}
360 	if (argc > 1)
361 		usage();
362 	if (argc == 1)
363 		host = argv[0];
364 	else
365 		host = "127.0.0.1";
366 
367 	if ((target_addr = inet_addr(host)) != -1) {
368 		hp = &bogus;
369 		hp->h_length = sizeof(target_addr);
370 		hp->h_addr_list = (char **)malloc(2 * sizeof(char *));
371 		if (hp->h_addr_list == NULL)
372 			logit(LOG_ERR, errno, "malloc");
373 		hp->h_addr_list[0] = malloc(hp->h_length);
374 		if (hp->h_addr_list[0] == NULL)
375 			logit(LOG_ERR, errno, "malloc");
376 		memcpy(hp->h_addr_list[0], &target_addr, sizeof(hp->h_addr_list[0]));
377 		hp->h_addr_list[1] = NULL;
378 	} else
379 		hp = gethostbyname(host);
380 
381 	if (hp == NULL || hp->h_length != sizeof(target_addr)) {
382 		fprintf(stderr, "mrinfo: %s: no such host\n", argv[0]);
383 		exit(1);
384 	}
385 	if (debug)
386 		fprintf(stderr, "Debug level %u\n", debug);
387 
388 	/* Check all addresses; mrouters often have unreachable interfaces */
389 	for (curaddr = 0; hp->h_addr_list[curaddr] != NULL; curaddr++) {
390 	    memcpy(&target_addr, hp->h_addr_list[curaddr], sizeof(target_addr));
391 	    {			/* Find a good local address for us. */
392 		int     udp;
393 		struct sockaddr_in addr;
394 		socklen_t addrlen = sizeof(addr);
395 
396 		memset(&addr, 0, sizeof(addr));
397 		addr.sin_family = AF_INET;
398 #if (defined(BSD) && (BSD >= 199103))
399 		addr.sin_len = sizeof addr;
400 #endif
401 		addr.sin_addr.s_addr = target_addr;
402 		addr.sin_port = htons(2000);	/* any port over 1024 will
403 						 * do... */
404 		if ((udp = socket(AF_INET, SOCK_DGRAM, 0)) < 0
405 		|| connect(udp, (struct sockaddr *) & addr, sizeof(addr)) < 0
406 		    || getsockname(udp, (struct sockaddr *) & addr, &addrlen) < 0) {
407 			perror("Determining local address");
408 			exit(1);
409 		}
410 		close(udp);
411 		our_addr = addr.sin_addr.s_addr;
412 	    }
413 
414 	    tries = 0;
415 	    trynew = 1;
416 	    /*
417 	     * New strategy: send 'ask2' for two timeouts, then fall back
418 	     * to 'ask', since it's not very likely that we are going to
419 	     * find someone who only responds to 'ask' these days
420 	     */
421 	    ask2(target_addr);
422 
423 	    gettimeofday(&et, 0);
424 	    et.tv_sec += timeout;
425 
426 	    /* Main receive loop */
427 	    for (;;) {
428 		struct pollfd set[1];
429 		struct timeval tv, now;
430 		int     count, recvlen;
431 		socklen_t dummy;
432 		u_int32_t src, dst, group;
433 		struct ip *ip;
434 		struct igmp *igmp;
435 		int     ipdatalen, iphdrlen, igmpdatalen;
436 
437 		set[0].fd = igmp_socket;
438 		set[0].events = POLLIN;
439 
440 		gettimeofday(&now, 0);
441 		tv.tv_sec = et.tv_sec - now.tv_sec;
442 		tv.tv_usec = et.tv_usec - now.tv_usec;
443 
444 		if (tv.tv_usec < 0) {
445 			tv.tv_usec += 1000000L;
446 			--tv.tv_sec;
447 		}
448 		if (tv.tv_sec < 0)
449 			tv.tv_sec = tv.tv_usec = 0;
450 
451 		count = poll(set, 1, tv.tv_sec * 1000 + tv.tv_usec / 1000);
452 
453 		if (count < 0) {
454 			if (errno != EINTR)
455 				perror("select");
456 			continue;
457 		} else if (count == 0) {
458 			logit(LOG_DEBUG, 0, "Timed out receiving neighbor lists");
459 			if (++tries > retries)
460 				break;
461 			/* If we've tried ASK_NEIGHBORS2 twice with
462 			 * no response, fall back to ASK_NEIGHBORS
463 			 */
464 			if (tries == 2 && target_level == 0)
465 				trynew = 0;
466 			if (target_level == 0 && trynew == 0)
467 				ask(target_addr);
468 			else
469 				ask2(target_addr);
470 			gettimeofday(&et, 0);
471 			et.tv_sec += timeout;
472 			continue;
473 		}
474 		recvlen = recvfrom(igmp_socket, recv_buf, RECV_BUF_SIZE,
475 				   0, NULL, &dummy);
476 		if (recvlen <= 0) {
477 			if (recvlen && errno != EINTR)
478 				perror("recvfrom");
479 			continue;
480 		}
481 
482 		if (recvlen < sizeof(struct ip)) {
483 			logit(LOG_WARNING, 0,
484 			    "packet too short (%u bytes) for IP header",
485 			    recvlen);
486 			continue;
487 		}
488 		ip = (struct ip *) recv_buf;
489 		if (ip->ip_p == 0)
490 			continue;	/* Request to install cache entry */
491 		src = ip->ip_src.s_addr;
492 		dst = ip->ip_dst.s_addr;
493 		iphdrlen = ip->ip_hl << 2;
494 		ipdatalen = ip->ip_len;
495 		if (iphdrlen + ipdatalen != recvlen) {
496 		    logit(LOG_WARNING, 0,
497 		      "packet shorter (%u bytes) than hdr+data length (%u+%u)",
498 		      recvlen, iphdrlen, ipdatalen);
499 		    continue;
500 		}
501 		igmp = (struct igmp *) (recv_buf + iphdrlen);
502 		group = igmp->igmp_group.s_addr;
503 		igmpdatalen = ipdatalen - IGMP_MINLEN;
504 		if (igmpdatalen < 0) {
505 		    logit(LOG_WARNING, 0,
506 			"IP data field too short (%u bytes) for IGMP, from %s",
507 			ipdatalen, inet_fmt(src));
508 		    continue;
509 		}
510 		if (igmp->igmp_type != IGMP_DVMRP)
511 			continue;
512 
513 		switch (igmp->igmp_code) {
514 		case DVMRP_NEIGHBORS:
515 		case DVMRP_NEIGHBORS2:
516 			if (src != target_addr) {
517 				fprintf(stderr, "mrinfo: got reply from %s",
518 					inet_fmt(src));
519 				fprintf(stderr, " instead of %s\n",
520 					inet_fmt(target_addr));
521 				/*continue;*/
522 			}
523 			break;
524 		default:
525 			continue;	/* ignore all other DVMRP messages */
526 		}
527 
528 		switch (igmp->igmp_code) {
529 
530 		case DVMRP_NEIGHBORS:
531 			if (group) {
532 				/* knows about DVMRP_NEIGHBORS2 msg */
533 				if (target_level == 0) {
534 					target_level = ntohl(group);
535 					ask2(target_addr);
536 				}
537 			} else {
538 				accept_neighbors(src, dst, (u_char *)(igmp + 1),
539 						 igmpdatalen, ntohl(group));
540 				exit(0);
541 			}
542 			break;
543 
544 		case DVMRP_NEIGHBORS2:
545 			accept_neighbors2(src, dst, (u_char *)(igmp + 1),
546 					  igmpdatalen, ntohl(group));
547 			exit(0);
548 		}
549 	    }
550 	}
551 	exit(1);
552 }
553 
554 /* dummies */
555 void accept_probe(u_int32_t src, u_int32_t dst, char *p, int datalen,
556 		  u_int32_t level)
557 {
558 }
559 void accept_group_report(u_int32_t src, u_int32_t dst, u_int32_t group,
560 			 int r_type)
561 {
562 }
563 void accept_neighbor_request2(u_int32_t src, u_int32_t dst)
564 {
565 }
566 void accept_report(u_int32_t src, u_int32_t dst, char *p, int datalen,
567 		   u_int32_t level)
568 {
569 }
570 void accept_neighbor_request(u_int32_t src, u_int32_t dst)
571 {
572 }
573 void accept_prune(u_int32_t src, u_int32_t dst, char *p, int datalen)
574 {
575 }
576 void accept_graft(u_int32_t src, u_int32_t dst, char *p, int datalen)
577 {
578 }
579 void accept_g_ack(u_int32_t src, u_int32_t dst, char *p, int datalen)
580 {
581 }
582 void add_table_entry(u_int32_t origin, u_int32_t mcastgrp)
583 {
584 }
585 void check_vif_state(void)
586 {
587 }
588 void accept_leave_message(u_int32_t src, u_int32_t dst, u_int32_t group)
589 {
590 }
591 void accept_mtrace(u_int32_t src, u_int32_t dst, u_int32_t group, char *data,
592 		   u_int no, int datalen)
593 {
594 }
595 void accept_membership_query(u_int32_t src, u_int32_t dst, u_int32_t group,
596 			     int tmo)
597 {
598 }
599 void accept_info_request(u_int32_t src, u_int32_t dst, u_char *p, int datalen)
600 {
601 }
602 void accept_info_reply(u_int32_t src, u_int32_t dst, u_char *p, int datalen)
603 {
604 }
605