mrinfo.c revision 1.29 1 /* $NetBSD: mrinfo.c,v 1.29 2011/08/31 13:32:38 joerg 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 1.29 2011/08/31 13:32:38 joerg 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 const 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 __dead void usage(void);
115
116 /* logit() prototyped in defs.h */
117
118
119 const char *
120 inet_name(u_int32_t addr)
121 {
122 struct hostent *e;
123 struct in_addr in;
124
125 if (addr == 0)
126 return "local";
127
128 if (nflag ||
129 (e = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET)) == NULL) {
130 in.s_addr = addr;
131 return (inet_ntoa(in));
132 }
133 return (e->h_name);
134 }
135
136 /*
137 * Log errors and other messages to stderr, according to the severity of the
138 * message and the current debug level. For errors of severity LOG_ERR or
139 * worse, terminate the program.
140 */
141 void
142 logit(int severity, int syserr, const char *format, ...)
143 {
144 va_list ap;
145
146 switch (debug) {
147 case 0:
148 if (severity > LOG_WARNING)
149 return;
150 case 1:
151 if (severity > LOG_NOTICE)
152 return;
153 case 2:
154 if (severity > LOG_INFO)
155 return;
156 default:
157 if (severity == LOG_WARNING)
158 fprintf(stderr, "warning - ");
159 va_start(ap, format);
160 vfprintf(stderr, format, ap);
161 va_end(ap);
162 if (syserr == 0)
163 fprintf(stderr, "\n");
164 else
165 fprintf(stderr, ": %s\n", strerror(syserr));
166 }
167
168 if (severity <= LOG_ERR)
169 exit(1);
170 }
171
172 /*
173 * Send a neighbors-list request.
174 */
175 void
176 ask(u_int32_t dst)
177 {
178 send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS,
179 htonl(MROUTED_LEVEL), 0);
180 }
181
182 void
183 ask2(u_int32_t dst)
184 {
185 send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS2,
186 htonl(MROUTED_LEVEL), 0);
187 }
188
189 /*
190 * Process an incoming neighbor-list message.
191 */
192 void
193 accept_neighbors(u_int32_t src, u_int32_t dst, u_char *p, int datalen,
194 u_int32_t level)
195 {
196 u_char *ep = p + datalen;
197 #define GET_ADDR(a) (a = ((u_int32_t)*p++ << 24), a += ((u_int32_t)*p++ << 16),\
198 a += ((u_int32_t)*p++ << 8), a += *p++)
199
200 printf("%s (%s):\n", inet_fmt(src), inet_name(src));
201 while (p < ep) {
202 u_int32_t laddr;
203 u_char metric;
204 u_char thresh;
205 int ncount;
206
207 GET_ADDR(laddr);
208 laddr = htonl(laddr);
209 metric = *p++;
210 thresh = *p++;
211 ncount = *p++;
212 while (--ncount >= 0) {
213 u_int32_t neighbor;
214 GET_ADDR(neighbor);
215 neighbor = htonl(neighbor);
216 printf(" %s -> ", inet_fmt(laddr));
217 printf("%s (%s) [%d/%d]\n",
218 inet_fmt(neighbor),
219 inet_name(neighbor), metric, thresh);
220 }
221 }
222 }
223
224 void
225 accept_neighbors2(u_int32_t src, u_int32_t dst, u_char *p, int datalen,
226 u_int32_t level)
227 {
228 u_char *ep = p + datalen;
229 u_int broken_cisco = ((level & 0xffff) == 0x020a); /* 10.2 */
230 /* well, only possibly_broken_cisco, but that's too long to type. */
231
232 printf("%s (%s) [version %d.%d", inet_fmt(src),
233 inet_name(src), level & 0xff, (level >> 8) & 0xff);
234 if ((level >> 16) & NF_LEAF) { printf (",leaf"); }
235 if ((level >> 16) & NF_PRUNE) { printf (",prune"); }
236 if ((level >> 16) & NF_GENID) { printf (",genid"); }
237 if ((level >> 16) & NF_MTRACE) { printf (",mtrace"); }
238 printf ("]:\n");
239
240 while (p < ep) {
241 u_char metric;
242 u_char thresh;
243 u_char flags;
244 int ncount;
245 u_int32_t laddr = *(u_int32_t*)p;
246
247 p += 4;
248 metric = *p++;
249 thresh = *p++;
250 flags = *p++;
251 ncount = *p++;
252 if (broken_cisco && ncount == 0) /* dumb Ciscos */
253 ncount = 1;
254 if (broken_cisco && ncount > 15) /* dumb Ciscos */
255 ncount = ncount & 0xf;
256 while (--ncount >= 0 && p < ep) {
257 u_int32_t neighbor = *(u_int32_t*)p;
258 p += 4;
259 printf(" %s -> ", inet_fmt(laddr));
260 printf("%s (%s) [%d/%d",
261 inet_fmt(neighbor),
262 inet_name(neighbor), metric, thresh);
263 if (flags & DVMRP_NF_TUNNEL)
264 printf("/tunnel");
265 if (flags & DVMRP_NF_SRCRT)
266 printf("/srcrt");
267 if (flags & DVMRP_NF_PIM)
268 printf("/pim");
269 if (flags & DVMRP_NF_QUERIER)
270 printf("/querier");
271 if (flags & DVMRP_NF_DISABLED)
272 printf("/disabled");
273 if (flags & DVMRP_NF_DOWN)
274 printf("/down");
275 if (flags & DVMRP_NF_LEAF)
276 printf("/leaf");
277 printf("]\n");
278 }
279 }
280 }
281
282 int
283 get_number(int *var, int deflt, char ***pargv, int *pargc)
284 {
285 if ((*pargv)[0][2] == '\0') { /* Get the value from the next
286 * argument */
287 if (*pargc > 1 && isdigit((unsigned char)(*pargv)[1][0])) {
288 (*pargv)++, (*pargc)--;
289 *var = atoi((*pargv)[0]);
290 return 1;
291 } else if (deflt >= 0) {
292 *var = deflt;
293 return 1;
294 } else
295 return 0;
296 } else { /* Get value from the rest of this argument */
297 if (isdigit((unsigned char)(*pargv)[0][2])) {
298 *var = atoi((*pargv)[0] + 2);
299 return 1;
300 } else {
301 return 0;
302 }
303 }
304 }
305
306 void
307 usage(void)
308 {
309 fprintf(stderr,
310 "usage: mrinfo [-n] [-t timeout] [-r retries] [router]\n");
311 exit(1);
312 }
313
314 int
315 main(int argc, char *argv[])
316 {
317 int tries;
318 int trynew;
319 struct timeval et;
320 struct hostent *hp;
321 struct hostent bogus;
322 const char *host;
323 int curaddr;
324
325 if (geteuid() != 0) {
326 fprintf(stderr, "mrinfo: must be root\n");
327 exit(1);
328 }
329 init_igmp();
330 if (setuid(getuid()) == -1)
331 logit(LOG_ERR, errno, "setuid");
332
333 setlinebuf(stderr);
334
335 argv++, argc--;
336 while (argc > 0 && argv[0][0] == '-') {
337 switch (argv[0][1]) {
338 case 'd':
339 if (!get_number(&debug, DEFAULT_DEBUG, &argv, &argc))
340 usage();
341 break;
342 case 'n':
343 ++nflag;
344 break;
345 case 'r':
346 if (!get_number(&retries, -1, &argv, &argc))
347 usage();
348 break;
349 case 't':
350 if (!get_number(&timeout, -1, &argv, &argc))
351 usage();
352 break;
353 default:
354 usage();
355 }
356 argv++, argc--;
357 }
358 if (argc > 1)
359 usage();
360 if (argc == 1)
361 host = argv[0];
362 else
363 host = "127.0.0.1";
364
365 if ((target_addr = inet_addr(host)) != (in_addr_t)-1) {
366 hp = &bogus;
367 hp->h_length = sizeof(target_addr);
368 hp->h_addr_list = (char **)malloc(2 * sizeof(char *));
369 if (hp->h_addr_list == NULL)
370 logit(LOG_ERR, errno, "malloc");
371 hp->h_addr_list[0] = malloc(hp->h_length);
372 if (hp->h_addr_list[0] == NULL)
373 logit(LOG_ERR, errno, "malloc");
374 memcpy(hp->h_addr_list[0], &target_addr, hp->h_length);
375 hp->h_addr_list[1] = NULL;
376 } else
377 hp = gethostbyname(host);
378
379 if (hp == NULL || hp->h_length != sizeof(target_addr)) {
380 fprintf(stderr, "mrinfo: %s: no such host\n", argv[0]);
381 exit(1);
382 }
383 if (debug)
384 fprintf(stderr, "Debug level %u\n", debug);
385
386 /* Check all addresses; mrouters often have unreachable interfaces */
387 for (curaddr = 0; hp->h_addr_list[curaddr] != NULL; curaddr++) {
388 memcpy(&target_addr, hp->h_addr_list[curaddr], sizeof(target_addr));
389 { /* Find a good local address for us. */
390 int udp;
391 struct sockaddr_in addr;
392 socklen_t addrlen = sizeof(addr);
393
394 memset(&addr, 0, sizeof(addr));
395 addr.sin_family = AF_INET;
396 #if (defined(BSD) && (BSD >= 199103))
397 addr.sin_len = sizeof addr;
398 #endif
399 addr.sin_addr.s_addr = target_addr;
400 addr.sin_port = htons(2000); /* any port over 1024 will
401 * do... */
402 if ((udp = socket(AF_INET, SOCK_DGRAM, 0)) < 0
403 || connect(udp, (struct sockaddr *) & addr, sizeof(addr)) < 0
404 || getsockname(udp, (struct sockaddr *) & addr, &addrlen) < 0) {
405 perror("Determining local address");
406 exit(1);
407 }
408 close(udp);
409 our_addr = addr.sin_addr.s_addr;
410 }
411
412 tries = 0;
413 trynew = 1;
414 /*
415 * New strategy: send 'ask2' for two timeouts, then fall back
416 * to 'ask', since it's not very likely that we are going to
417 * find someone who only responds to 'ask' these days
418 */
419 ask2(target_addr);
420
421 gettimeofday(&et, 0);
422 et.tv_sec += timeout;
423
424 /* Main receive loop */
425 for (;;) {
426 struct pollfd set[1];
427 struct timeval tv, now;
428 int count, recvlen;
429 socklen_t dummy;
430 u_int32_t src, dst, group;
431 struct ip *ip;
432 struct igmp *igmp;
433 int ipdatalen, iphdrlen, igmpdatalen;
434
435 set[0].fd = igmp_socket;
436 set[0].events = POLLIN;
437
438 gettimeofday(&now, 0);
439 tv.tv_sec = et.tv_sec - now.tv_sec;
440 tv.tv_usec = et.tv_usec - now.tv_usec;
441
442 if (tv.tv_usec < 0) {
443 tv.tv_usec += 1000000L;
444 --tv.tv_sec;
445 }
446 if (tv.tv_sec < 0)
447 tv.tv_sec = tv.tv_usec = 0;
448
449 count = poll(set, 1, tv.tv_sec * 1000 + tv.tv_usec / 1000);
450
451 if (count < 0) {
452 if (errno != EINTR)
453 perror("select");
454 continue;
455 } else if (count == 0) {
456 logit(LOG_DEBUG, 0, "Timed out receiving neighbor lists");
457 if (++tries > retries)
458 break;
459 /* If we've tried ASK_NEIGHBORS2 twice with
460 * no response, fall back to ASK_NEIGHBORS
461 */
462 if (tries == 2 && target_level == 0)
463 trynew = 0;
464 if (target_level == 0 && trynew == 0)
465 ask(target_addr);
466 else
467 ask2(target_addr);
468 gettimeofday(&et, 0);
469 et.tv_sec += timeout;
470 continue;
471 }
472 recvlen = recvfrom(igmp_socket, recv_buf, RECV_BUF_SIZE,
473 0, NULL, &dummy);
474 if (recvlen <= 0) {
475 if (recvlen && errno != EINTR)
476 perror("recvfrom");
477 continue;
478 }
479
480 if (recvlen < (int)sizeof(struct ip)) {
481 logit(LOG_WARNING, 0,
482 "packet too short (%u bytes) for IP header",
483 recvlen);
484 continue;
485 }
486 ip = (struct ip *) recv_buf;
487 if (ip->ip_p == 0)
488 continue; /* Request to install cache entry */
489 src = ip->ip_src.s_addr;
490 dst = ip->ip_dst.s_addr;
491 iphdrlen = ip->ip_hl << 2;
492 ipdatalen = ip->ip_len;
493 if (iphdrlen + ipdatalen != recvlen) {
494 logit(LOG_WARNING, 0,
495 "packet shorter (%u bytes) than hdr+data length (%u+%u)",
496 recvlen, iphdrlen, ipdatalen);
497 continue;
498 }
499 igmp = (struct igmp *) (recv_buf + iphdrlen);
500 group = igmp->igmp_group.s_addr;
501 igmpdatalen = ipdatalen - IGMP_MINLEN;
502 if (igmpdatalen < 0) {
503 logit(LOG_WARNING, 0,
504 "IP data field too short (%u bytes) for IGMP, from %s",
505 ipdatalen, inet_fmt(src));
506 continue;
507 }
508 if (igmp->igmp_type != IGMP_DVMRP)
509 continue;
510
511 switch (igmp->igmp_code) {
512 case DVMRP_NEIGHBORS:
513 case DVMRP_NEIGHBORS2:
514 if (src != target_addr) {
515 fprintf(stderr, "mrinfo: got reply from %s",
516 inet_fmt(src));
517 fprintf(stderr, " instead of %s\n",
518 inet_fmt(target_addr));
519 /*continue;*/
520 }
521 break;
522 default:
523 continue; /* ignore all other DVMRP messages */
524 }
525
526 switch (igmp->igmp_code) {
527
528 case DVMRP_NEIGHBORS:
529 if (group) {
530 /* knows about DVMRP_NEIGHBORS2 msg */
531 if (target_level == 0) {
532 target_level = ntohl(group);
533 ask2(target_addr);
534 }
535 } else {
536 accept_neighbors(src, dst, (u_char *)(igmp + 1),
537 igmpdatalen, ntohl(group));
538 exit(0);
539 }
540 break;
541
542 case DVMRP_NEIGHBORS2:
543 accept_neighbors2(src, dst, (u_char *)(igmp + 1),
544 igmpdatalen, ntohl(group));
545 exit(0);
546 }
547 }
548 }
549 exit(1);
550 }
551
552 /* dummies */
553 void accept_probe(u_int32_t src, u_int32_t dst, char *p, int datalen,
554 u_int32_t level)
555 {
556 }
557 void accept_group_report(u_int32_t src, u_int32_t dst, u_int32_t group,
558 int r_type)
559 {
560 }
561 void accept_neighbor_request2(u_int32_t src, u_int32_t dst)
562 {
563 }
564 void accept_report(u_int32_t src, u_int32_t dst, char *p, int datalen,
565 u_int32_t level)
566 {
567 }
568 void accept_neighbor_request(u_int32_t src, u_int32_t dst)
569 {
570 }
571 void accept_prune(u_int32_t src, u_int32_t dst, char *p, int datalen)
572 {
573 }
574 void accept_graft(u_int32_t src, u_int32_t dst, char *p, int datalen)
575 {
576 }
577 void accept_g_ack(u_int32_t src, u_int32_t dst, char *p, int datalen)
578 {
579 }
580 void add_table_entry(u_int32_t origin, u_int32_t mcastgrp)
581 {
582 }
583 void check_vif_state(void)
584 {
585 }
586 void accept_leave_message(u_int32_t src, u_int32_t dst, u_int32_t group)
587 {
588 }
589 void accept_mtrace(u_int32_t src, u_int32_t dst, u_int32_t group, char *data,
590 u_int no, int datalen)
591 {
592 }
593 void accept_membership_query(u_int32_t src, u_int32_t dst, u_int32_t group,
594 int tmo)
595 {
596 }
597 void accept_info_request(u_int32_t src, u_int32_t dst, u_char *p, int datalen)
598 {
599 }
600 void accept_info_reply(u_int32_t src, u_int32_t dst, u_char *p, int datalen)
601 {
602 }
603