xref: /netbsd-src/usr.sbin/mrinfo/mrinfo.c (revision 81b108b45f75f89f1e3ffad9fb6f074e771c0935)
1 /*	$NetBSD: mrinfo.c,v 1.4 1995/12/10 11:00:51 mycroft 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) Xerox Corporation 1992. All rights reserved.
49  *
50  * License is granted to copy, to use, and to make and to use derivative works
51  * for research and evaluation purposes, provided that Xerox is acknowledged
52  * in all documentation pertaining to any such copy or derivative work. Xerox
53  * grants no other licenses expressed or implied. The Xerox trade name should
54  * not be used in any advertising without its written permission.
55  *
56  * XEROX CORPORATION MAKES NO REPRESENTATIONS CONCERNING EITHER THE
57  * MERCHANTABILITY OF THIS SOFTWARE OR THE SUITABILITY OF THIS SOFTWARE FOR
58  * ANY PARTICULAR PURPOSE.  The software is provided "as is" without express
59  * or implied warranty of any kind.
60  *
61  * These notices must be retained in any copies of any part of this software.
62  */
63 
64 #ifndef lint
65 static char rcsid[] =
66     "@(#) $NetBSD: mrinfo.c,v 1.4 1995/12/10 11:00:51 mycroft Exp $";
67 /*  original rcsid:
68     "@(#) Header: mrinfo.c,v 1.6 93/04/08 15:14:16 van Exp (LBL)";
69 */
70 #endif
71 
72 #include <string.h>
73 #include <netdb.h>
74 #include <sys/time.h>
75 #include "defs.h"
76 #include <arpa/inet.h>
77 #ifdef __STDC__
78 #include <stdarg.h>
79 #else
80 #include <varargs.h>
81 #endif
82 
83 #define DEFAULT_TIMEOUT	4	/* How long to wait before retrying requests */
84 #define DEFAULT_RETRIES 3	/* How many times to ask each router */
85 
86 u_int32_t	our_addr, target_addr = 0;	/* in NET order */
87 int     debug = 0;
88 int	nflag = 0;
89 int     retries = DEFAULT_RETRIES;
90 int     timeout = DEFAULT_TIMEOUT;
91 int	target_level = 0;
92 vifi_t  numvifs;		/* to keep loader happy */
93 				/* (see COPY_TABLES macro called in kern.c) */
94 
95 char *			inet_name __P((u_int32_t addr));
96 void			ask __P((u_int32_t dst));
97 void			ask2 __P((u_int32_t dst));
98 int			get_number __P((int *var, int deflt, char ***pargv,
99 					int *pargc));
100 u_int32_t			host_addr __P((char *name));
101 void			usage __P((void));
102 
103 /* to shut up -Wstrict-prototypes */
104 int			main __P((int argc, char *argv[]));
105 
106 
107 char   *
108 inet_name(addr)
109 	u_int32_t  addr;
110 {
111 	struct hostent *e;
112 	struct in_addr in;
113 
114 	if (addr == 0)
115 		return "local";
116 
117 	if (nflag ||
118 	    (e = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET)) == NULL) {
119 		in.s_addr = addr;
120 		return (inet_ntoa(in));
121 	}
122 	return (e->h_name);
123 }
124 
125 /*
126  * Log errors and other messages to stderr, according to the severity of the
127  * message and the current debug level.  For errors of severity LOG_ERR or
128  * worse, terminate the program.
129  */
130 #ifdef __STDC__
131 void
132 log(int severity, int syserr, char *format, ...)
133 {
134 	va_list ap;
135 	char    fmt[100];
136 
137 	va_start(ap, format);
138 #else
139 void
140 log(severity, syserr, format, va_alist)
141 	int     severity, syserr;
142 	char   *format;
143 	va_dcl
144 {
145 	va_list ap;
146 	char    fmt[100];
147 
148 	va_start(ap);
149 #endif
150 	switch (debug) {
151 	case 0:
152 		if (severity > LOG_WARNING)
153 			return;
154 	case 1:
155 		if (severity > LOG_NOTICE)
156 			return;
157 	case 2:
158 		if (severity > LOG_INFO)
159 			return;
160 	default:
161 		fmt[0] = '\0';
162 		if (severity == LOG_WARNING)
163 			strcat(fmt, "warning - ");
164 		strncat(fmt, format, 80);
165 		vfprintf(stderr, fmt, ap);
166 		if (syserr == 0)
167 			fprintf(stderr, "\n");
168 		else if (syserr < sys_nerr)
169 			fprintf(stderr, ": %s\n", sys_errlist[syserr]);
170 		else
171 			fprintf(stderr, ": errno %d\n", syserr);
172 	}
173 
174 	if (severity <= LOG_ERR)
175 		exit(-1);
176 }
177 
178 /*
179  * Send a neighbors-list request.
180  */
181 void
182 ask(dst)
183 	u_int32_t  dst;
184 {
185 	send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS,
186 			htonl(MROUTED_LEVEL), 0);
187 }
188 
189 void
190 ask2(dst)
191 	u_int32_t  dst;
192 {
193 	send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS2,
194 			htonl(MROUTED_LEVEL), 0);
195 }
196 
197 /*
198  * Process an incoming neighbor-list message.
199  */
200 void
201 accept_neighbors(src, dst, p, datalen, level)
202 	u_int32_t	src, dst, level;
203 	u_char	*p;
204 	int     datalen;
205 {
206 	u_char *ep = p + datalen;
207 #define GET_ADDR(a) (a = ((u_int32_t)*p++ << 24), a += ((u_int32_t)*p++ << 16),\
208 		     a += ((u_int32_t)*p++ << 8), a += *p++)
209 
210 	printf("%s (%s):\n", inet_fmt(src, s1), inet_name(src));
211 	while (p < ep) {
212 		register u_int32_t laddr;
213 		register u_char metric;
214 		register u_char thresh;
215 		register int ncount;
216 
217 		GET_ADDR(laddr);
218 		laddr = htonl(laddr);
219 		metric = *p++;
220 		thresh = *p++;
221 		ncount = *p++;
222 		while (--ncount >= 0) {
223 			register u_int32_t neighbor;
224 			GET_ADDR(neighbor);
225 			neighbor = htonl(neighbor);
226 			printf("  %s -> ", inet_fmt(laddr, s1));
227 			printf("%s (%s) [%d/%d]\n", inet_fmt(neighbor, s1),
228 			       inet_name(neighbor), metric, thresh);
229 		}
230 	}
231 }
232 
233 void
234 accept_neighbors2(src, dst, p, datalen, level)
235 	u_int32_t	src, dst, level;
236 	u_char	*p;
237 	int     datalen;
238 {
239 	u_char *ep = p + datalen;
240 	u_int broken_cisco = ((level & 0xffff) == 0x020a); /* 10.2 */
241 	/* well, only possibly_broken_cisco, but that's too long to type. */
242 
243 	printf("%s (%s) [version %d.%d", inet_fmt(src, s1), inet_name(src),
244 	       level & 0xff, (level >> 8) & 0xff);
245 	if ((level >> 16) & NF_LEAF)   { printf (",leaf"); }
246 	if ((level >> 16) & NF_PRUNE)  { printf (",prune"); }
247 	if ((level >> 16) & NF_GENID)  { printf (",genid"); }
248 	if ((level >> 16) & NF_MTRACE) { printf (",mtrace"); }
249 	printf ("]:\n");
250 
251 	while (p < ep) {
252 		register u_char metric;
253 		register u_char thresh;
254 		register u_char flags;
255 		register int ncount;
256 		register u_int32_t laddr = *(u_int32_t*)p;
257 
258 		p += 4;
259 		metric = *p++;
260 		thresh = *p++;
261 		flags = *p++;
262 		ncount = *p++;
263 		if (broken_cisco && ncount == 0)	/* dumb Ciscos */
264 			ncount = 1;
265 		if (broken_cisco && ncount > 15)	/* dumb Ciscos */
266 			ncount = ncount & 0xf;
267 		while (--ncount >= 0 && p < ep) {
268 			register u_int32_t neighbor = *(u_int32_t*)p;
269 			p += 4;
270 			printf("  %s -> ", inet_fmt(laddr, s1));
271 			printf("%s (%s) [%d/%d", inet_fmt(neighbor, s1),
272 			       inet_name(neighbor), metric, thresh);
273 			if (flags & DVMRP_NF_TUNNEL)
274 				printf("/tunnel");
275 			if (flags & DVMRP_NF_SRCRT)
276 				printf("/srcrt");
277 			if (flags & DVMRP_NF_PIM)
278 				printf("/pim");
279 			if (flags & DVMRP_NF_QUERIER)
280 				printf("/querier");
281 			if (flags & DVMRP_NF_DISABLED)
282 				printf("/disabled");
283 			if (flags & DVMRP_NF_DOWN)
284 				printf("/down");
285 			if (flags & DVMRP_NF_LEAF)
286 				printf("/leaf");
287 			printf("]\n");
288 		}
289 	}
290 }
291 
292 int
293 get_number(var, deflt, pargv, pargc)
294 	int    *var, *pargc, deflt;
295 	char ***pargv;
296 {
297 	if ((*pargv)[0][2] == '\0') {	/* Get the value from the next
298 					 * argument */
299 		if (*pargc > 1 && isdigit((*pargv)[1][0])) {
300 			(*pargv)++, (*pargc)--;
301 			*var = atoi((*pargv)[0]);
302 			return 1;
303 		} else if (deflt >= 0) {
304 			*var = deflt;
305 			return 1;
306 		} else
307 			return 0;
308 	} else {		/* Get value from the rest of this argument */
309 		if (isdigit((*pargv)[0][2])) {
310 			*var = atoi((*pargv)[0] + 2);
311 			return 1;
312 		} else {
313 			return 0;
314 		}
315 	}
316 }
317 
318 void
319 usage()
320 {
321 	fprintf(stderr,
322 	    "Usage: mrinfo [-n] [-t timeout] [-r retries] [router]\n");
323 	exit(1);
324 }
325 
326 int
327 main(argc, argv)
328 	int     argc;
329 	char   *argv[];
330 {
331 	int tries;
332 	int trynew;
333 	struct timeval et;
334 	struct hostent *hp;
335 	struct hostent bogus;
336 	char *host;
337 	int curaddr;
338 
339 	setlinebuf(stderr);
340 
341 	if (geteuid() != 0) {
342 		fprintf(stderr, "mrinfo: must be root\n");
343 		exit(1);
344 	}
345 	argv++, argc--;
346 	while (argc > 0 && argv[0][0] == '-') {
347 		switch (argv[0][1]) {
348 		case 'd':
349 			if (!get_number(&debug, DEFAULT_DEBUG, &argv, &argc))
350 				usage();
351 			break;
352 		case 'n':
353 			++nflag;
354 			break;
355 		case 'r':
356 			if (!get_number(&retries, -1, &argv, &argc))
357 				usage();
358 			break;
359 		case 't':
360 			if (!get_number(&timeout, -1, &argv, &argc))
361 				usage();
362 			break;
363 		default:
364 			usage();
365 		}
366 		argv++, argc--;
367 	}
368 	if (argc > 1)
369 		usage();
370 	if (argc == 1)
371 		host = argv[0];
372 	else
373 		host = "127.0.0.1";
374 
375 	if ((target_addr = inet_addr(host)) != -1) {
376 		hp = &bogus;
377 		hp->h_length = sizeof(target_addr);
378 		hp->h_addr_list = (char **)malloc(2 * sizeof(char *));
379 		hp->h_addr_list[0] = malloc(hp->h_length);
380 		memcpy(hp->h_addr_list[0], &target_addr, hp->h_length);
381 		hp->h_addr_list[1] = 0;
382 	} else
383 		hp = gethostbyname(host);
384 
385 	if (hp == NULL) {
386 		fprintf(stderr, "mrinfo: %s: no such host\n", argv[0]);
387 		exit(1);
388 	}
389 	if (debug)
390 		fprintf(stderr, "Debug level %u\n", debug);
391 
392 	init_igmp();
393 
394 	/* Check all addresses; mrouters often have unreachable interfaces */
395 	for (curaddr = 0; hp->h_addr_list[curaddr] != NULL; curaddr++) {
396 	    memcpy(&target_addr, hp->h_addr_list[curaddr], hp->h_length);
397 	    {			/* Find a good local address for us. */
398 		int     udp;
399 		struct sockaddr_in addr;
400 		int     addrlen = sizeof(addr);
401 
402 		addr.sin_family = AF_INET;
403 #if (defined(BSD) && (BSD >= 199103))
404 		addr.sin_len = sizeof addr;
405 #endif
406 		addr.sin_addr.s_addr = target_addr;
407 		addr.sin_port = htons(2000);	/* any port over 1024 will
408 						 * do... */
409 		if ((udp = socket(AF_INET, SOCK_DGRAM, 0)) < 0
410 		|| connect(udp, (struct sockaddr *) & addr, sizeof(addr)) < 0
411 		    || getsockname(udp, (struct sockaddr *) & addr, &addrlen) < 0) {
412 			perror("Determining local address");
413 			exit(-1);
414 		}
415 		close(udp);
416 		our_addr = addr.sin_addr.s_addr;
417 	    }
418 
419 	    tries = 0;
420 	    trynew = 1;
421 	    /*
422 	     * New strategy: send 'ask2' for two timeouts, then fall back
423 	     * to 'ask', since it's not very likely that we are going to
424 	     * find someone who only responds to 'ask' these days
425 	     */
426 	    ask2(target_addr);
427 
428 	    gettimeofday(&et, 0);
429 	    et.tv_sec += timeout;
430 
431 	    /* Main receive loop */
432 	    for (;;) {
433 		fd_set  fds;
434 		struct timeval tv, now;
435 		int     count, recvlen, dummy = 0;
436 		register u_int32_t src, dst, group;
437 		struct ip *ip;
438 		struct igmp *igmp;
439 		int     ipdatalen, iphdrlen, igmpdatalen;
440 
441 		FD_ZERO(&fds);
442 		FD_SET(igmp_socket, &fds);
443 
444 		gettimeofday(&now, 0);
445 		tv.tv_sec = et.tv_sec - now.tv_sec;
446 		tv.tv_usec = et.tv_usec - now.tv_usec;
447 
448 		if (tv.tv_usec < 0) {
449 			tv.tv_usec += 1000000L;
450 			--tv.tv_sec;
451 		}
452 		if (tv.tv_sec < 0)
453 			tv.tv_sec = tv.tv_usec = 0;
454 
455 		count = select(igmp_socket + 1, &fds, 0, 0, &tv);
456 
457 		if (count < 0) {
458 			if (errno != EINTR)
459 				perror("select");
460 			continue;
461 		} else if (count == 0) {
462 			log(LOG_DEBUG, 0, "Timed out receiving neighbor lists");
463 			if (++tries > retries)
464 				break;
465 			/* If we've tried ASK_NEIGHBORS2 twice with
466 			 * no response, fall back to ASK_NEIGHBORS
467 			 */
468 			if (tries == 2 && target_level == 0)
469 				trynew = 0;
470 			if (target_level == 0 && trynew == 0)
471 				ask(target_addr);
472 			else
473 				ask2(target_addr);
474 			gettimeofday(&et, 0);
475 			et.tv_sec += timeout;
476 			continue;
477 		}
478 		recvlen = recvfrom(igmp_socket, recv_buf, RECV_BUF_SIZE,
479 				   0, NULL, &dummy);
480 		if (recvlen <= 0) {
481 			if (recvlen && errno != EINTR)
482 				perror("recvfrom");
483 			continue;
484 		}
485 
486 		if (recvlen < sizeof(struct ip)) {
487 			log(LOG_WARNING, 0,
488 			    "packet too short (%u bytes) for IP header",
489 			    recvlen);
490 			continue;
491 		}
492 		ip = (struct ip *) recv_buf;
493 		if (ip->ip_p == 0)
494 			continue;	/* Request to install cache entry */
495 		src = ip->ip_src.s_addr;
496 		dst = ip->ip_dst.s_addr;
497 		iphdrlen = ip->ip_hl << 2;
498 		ipdatalen = ip->ip_len;
499 		if (iphdrlen + ipdatalen != recvlen) {
500 		    log(LOG_WARNING, 0,
501 		      "packet shorter (%u bytes) than hdr+data length (%u+%u)",
502 		      recvlen, iphdrlen, ipdatalen);
503 		    continue;
504 		}
505 		igmp = (struct igmp *) (recv_buf + iphdrlen);
506 		group = igmp->igmp_group.s_addr;
507 		igmpdatalen = ipdatalen - IGMP_MINLEN;
508 		if (igmpdatalen < 0) {
509 		    log(LOG_WARNING, 0,
510 			"IP data field too short (%u bytes) for IGMP, from %s",
511 			ipdatalen, inet_fmt(src, s1));
512 		    continue;
513 		}
514 		if (igmp->igmp_type != IGMP_DVMRP)
515 			continue;
516 
517 		switch (igmp->igmp_code) {
518 		case DVMRP_NEIGHBORS:
519 		case DVMRP_NEIGHBORS2:
520 			if (src != target_addr) {
521 				fprintf(stderr, "mrinfo: got reply from %s",
522 					inet_fmt(src, s1));
523 				fprintf(stderr, " instead of %s\n",
524 					inet_fmt(target_addr, s1));
525 				/*continue;*/
526 			}
527 			break;
528 		default:
529 			continue;	/* ignore all other DVMRP messages */
530 		}
531 
532 		switch (igmp->igmp_code) {
533 
534 		case DVMRP_NEIGHBORS:
535 			if (group) {
536 				/* knows about DVMRP_NEIGHBORS2 msg */
537 				if (target_level == 0) {
538 					target_level = ntohl(group);
539 					ask2(target_addr);
540 				}
541 			} else {
542 				accept_neighbors(src, dst, (u_char *)(igmp + 1),
543 						 igmpdatalen, ntohl(group));
544 				exit(0);
545 			}
546 			break;
547 
548 		case DVMRP_NEIGHBORS2:
549 			accept_neighbors2(src, dst, (u_char *)(igmp + 1),
550 					  igmpdatalen, ntohl(group));
551 			exit(0);
552 		}
553 	    }
554 	}
555 	exit(1);
556 }
557 
558 /* dummies */
559 void accept_probe(src, dst, p, datalen, level)
560 	u_int32_t src, dst, level;
561 	char *p;
562 	int datalen;
563 {
564 }
565 void accept_group_report(src, dst, group, r_type)
566 	u_int32_t src, dst, group;
567 	int r_type;
568 {
569 }
570 void accept_neighbor_request2(src, dst)
571 	u_int32_t src, dst;
572 {
573 }
574 void accept_report(src, dst, p, datalen, level)
575 	u_int32_t src, dst, level;
576 	char *p;
577 	int datalen;
578 {
579 }
580 void accept_neighbor_request(src, dst)
581 	u_int32_t src, dst;
582 {
583 }
584 void accept_prune(src, dst, p, datalen)
585 	u_int32_t src, dst;
586 	char *p;
587 	int datalen;
588 {
589 }
590 void accept_graft(src, dst, p, datalen)
591 	u_int32_t src, dst;
592 	char *p;
593 	int datalen;
594 {
595 }
596 void accept_g_ack(src, dst, p, datalen)
597 	u_int32_t src, dst;
598 	char *p;
599 	int datalen;
600 {
601 }
602 void add_table_entry(origin, mcastgrp)
603 	u_int32_t origin, mcastgrp;
604 {
605 }
606 void check_vif_state()
607 {
608 }
609 void accept_leave_message(src, dst, group)
610 	u_int32_t src, dst, group;
611 {
612 }
613 void accept_mtrace(src, dst, group, data, no, datalen)
614 	u_int32_t src, dst, group;
615 	char *data;
616 	u_int no;
617 	int datalen;
618 {
619 }
620 void accept_membership_query(src, dst, group, tmo)
621 	u_int32_t src, dst, group;
622 	int tmo;
623 {
624 }
625 void accept_info_request(src, dst, p, datalen)
626 	u_int32_t src, dst;
627 	u_char *p;
628 	int datalen;
629 {
630 }
631 void accept_info_reply(src, dst, p, datalen)
632 	u_int32_t src, dst;
633 	u_char *p;
634 	int datalen;
635 {
636 }
637