mrinfo.c revision 1.21 1 /* $NetBSD: mrinfo.c,v 1.21 2003/05/16 18:10:37 itojun 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 1.21 2003/05/16 18:10:37 itojun Exp $");
84 #endif
85 #endif
86
87 #include <string.h>
88 #include <netdb.h>
89 #include <sys/time.h>
90 #include <poll.h>
91 #include "defs.h"
92 #include <arpa/inet.h>
93 #include <stdarg.h>
94
95 #define DEFAULT_TIMEOUT 4 /* How long to wait before retrying requests */
96 #define DEFAULT_RETRIES 3 /* How many times to ask each router */
97
98 u_int32_t our_addr, target_addr = 0; /* in NET order */
99 int debug = 0;
100 int nflag = 0;
101 int retries = DEFAULT_RETRIES;
102 int timeout = DEFAULT_TIMEOUT;
103 int target_level = 0;
104 vifi_t numvifs; /* to keep loader happy */
105 /* (see COPY_TABLES macro called in kern.c) */
106
107 char * inet_name(u_int32_t addr);
108 void ask(u_int32_t dst);
109 void ask2(u_int32_t dst);
110 int get_number(int *var, int deflt, char ***pargv,
111 int *pargc);
112 u_int32_t host_addr(char *name);
113 void usage(void);
114
115 /* to shut up -Wstrict-prototypes */
116 int main(int argc, char *argv[]);
117 /* logit() prototyped in defs.h */
118
119
120 char *
121 inet_name(u_int32_t addr)
122 {
123 struct hostent *e;
124 struct in_addr in;
125
126 if (addr == 0)
127 return "local";
128
129 if (nflag ||
130 (e = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET)) == NULL) {
131 in.s_addr = addr;
132 return (inet_ntoa(in));
133 }
134 return (e->h_name);
135 }
136
137 /*
138 * Log errors and other messages to stderr, according to the severity of the
139 * message and the current debug level. For errors of severity LOG_ERR or
140 * worse, terminate the program.
141 */
142 void
143 logit(int severity, int syserr, const char *format, ...)
144 {
145 va_list ap;
146
147 switch (debug) {
148 case 0:
149 if (severity > LOG_WARNING)
150 return;
151 case 1:
152 if (severity > LOG_NOTICE)
153 return;
154 case 2:
155 if (severity > LOG_INFO)
156 return;
157 default:
158 if (severity == LOG_WARNING)
159 fprintf(stderr, "warning - ");
160 va_start(ap, format);
161 vfprintf(stderr, format, ap);
162 va_end(ap);
163 if (syserr == 0)
164 fprintf(stderr, "\n");
165 else
166 fprintf(stderr, ": %s\n", strerror(syserr));
167 }
168
169 if (severity <= LOG_ERR)
170 exit(1);
171 }
172
173 /*
174 * Send a neighbors-list request.
175 */
176 void
177 ask(u_int32_t dst)
178 {
179 send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS,
180 htonl(MROUTED_LEVEL), 0);
181 }
182
183 void
184 ask2(u_int32_t dst)
185 {
186 send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS2,
187 htonl(MROUTED_LEVEL), 0);
188 }
189
190 /*
191 * Process an incoming neighbor-list message.
192 */
193 void
194 accept_neighbors(u_int32_t src, u_int32_t dst, u_char *p, int datalen,
195 u_int32_t level)
196 {
197 u_char *ep = p + datalen;
198 #define GET_ADDR(a) (a = ((u_int32_t)*p++ << 24), a += ((u_int32_t)*p++ << 16),\
199 a += ((u_int32_t)*p++ << 8), a += *p++)
200
201 printf("%s (%s):\n", inet_fmt(src, s1, sizeof(s1)), inet_name(src));
202 while (p < ep) {
203 u_int32_t laddr;
204 u_char metric;
205 u_char thresh;
206 int ncount;
207
208 GET_ADDR(laddr);
209 laddr = htonl(laddr);
210 metric = *p++;
211 thresh = *p++;
212 ncount = *p++;
213 while (--ncount >= 0) {
214 u_int32_t neighbor;
215 GET_ADDR(neighbor);
216 neighbor = htonl(neighbor);
217 printf(" %s -> ", inet_fmt(laddr, s1, sizeof(s1)));
218 printf("%s (%s) [%d/%d]\n",
219 inet_fmt(neighbor, s1, sizeof(s1)),
220 inet_name(neighbor), metric, thresh);
221 }
222 }
223 }
224
225 void
226 accept_neighbors2(u_int32_t src, u_int32_t dst, u_char *p, int datalen,
227 u_int32_t level)
228 {
229 u_char *ep = p + datalen;
230 u_int broken_cisco = ((level & 0xffff) == 0x020a); /* 10.2 */
231 /* well, only possibly_broken_cisco, but that's too long to type. */
232
233 printf("%s (%s) [version %d.%d", inet_fmt(src, s1, sizeof(s1)),
234 inet_name(src), level & 0xff, (level >> 8) & 0xff);
235 if ((level >> 16) & NF_LEAF) { printf (",leaf"); }
236 if ((level >> 16) & NF_PRUNE) { printf (",prune"); }
237 if ((level >> 16) & NF_GENID) { printf (",genid"); }
238 if ((level >> 16) & NF_MTRACE) { printf (",mtrace"); }
239 printf ("]:\n");
240
241 while (p < ep) {
242 u_char metric;
243 u_char thresh;
244 u_char flags;
245 int ncount;
246 u_int32_t laddr = *(u_int32_t*)p;
247
248 p += 4;
249 metric = *p++;
250 thresh = *p++;
251 flags = *p++;
252 ncount = *p++;
253 if (broken_cisco && ncount == 0) /* dumb Ciscos */
254 ncount = 1;
255 if (broken_cisco && ncount > 15) /* dumb Ciscos */
256 ncount = ncount & 0xf;
257 while (--ncount >= 0 && p < ep) {
258 u_int32_t neighbor = *(u_int32_t*)p;
259 p += 4;
260 printf(" %s -> ", inet_fmt(laddr, s1, sizeof(s1)));
261 printf("%s (%s) [%d/%d",
262 inet_fmt(neighbor, s1, sizeof(s1)),
263 inet_name(neighbor), metric, thresh);
264 if (flags & DVMRP_NF_TUNNEL)
265 printf("/tunnel");
266 if (flags & DVMRP_NF_SRCRT)
267 printf("/srcrt");
268 if (flags & DVMRP_NF_PIM)
269 printf("/pim");
270 if (flags & DVMRP_NF_QUERIER)
271 printf("/querier");
272 if (flags & DVMRP_NF_DISABLED)
273 printf("/disabled");
274 if (flags & DVMRP_NF_DOWN)
275 printf("/down");
276 if (flags & DVMRP_NF_LEAF)
277 printf("/leaf");
278 printf("]\n");
279 }
280 }
281 }
282
283 int
284 get_number(int *var, int deflt, char ***pargv, int *pargc)
285 {
286 if ((*pargv)[0][2] == '\0') { /* Get the value from the next
287 * argument */
288 if (*pargc > 1 && isdigit((*pargv)[1][0])) {
289 (*pargv)++, (*pargc)--;
290 *var = atoi((*pargv)[0]);
291 return 1;
292 } else if (deflt >= 0) {
293 *var = deflt;
294 return 1;
295 } else
296 return 0;
297 } else { /* Get value from the rest of this argument */
298 if (isdigit((*pargv)[0][2])) {
299 *var = atoi((*pargv)[0] + 2);
300 return 1;
301 } else {
302 return 0;
303 }
304 }
305 }
306
307 void
308 usage(void)
309 {
310 fprintf(stderr,
311 "Usage: mrinfo [-n] [-t timeout] [-r retries] [router]\n");
312 exit(1);
313 }
314
315 int
316 main(int argc, char *argv[])
317 {
318 int tries;
319 int trynew;
320 struct timeval et;
321 struct hostent *hp;
322 struct hostent bogus;
323 char *host;
324 int curaddr;
325
326 if (geteuid() != 0) {
327 fprintf(stderr, "mrinfo: must be root\n");
328 exit(1);
329 }
330 init_igmp();
331 if (setuid(getuid()) == -1)
332 logit(LOG_ERR, errno, "setuid");
333
334 setlinebuf(stderr);
335
336 argv++, argc--;
337 while (argc > 0 && argv[0][0] == '-') {
338 switch (argv[0][1]) {
339 case 'd':
340 if (!get_number(&debug, DEFAULT_DEBUG, &argv, &argc))
341 usage();
342 break;
343 case 'n':
344 ++nflag;
345 break;
346 case 'r':
347 if (!get_number(&retries, -1, &argv, &argc))
348 usage();
349 break;
350 case 't':
351 if (!get_number(&timeout, -1, &argv, &argc))
352 usage();
353 break;
354 default:
355 usage();
356 }
357 argv++, argc--;
358 }
359 if (argc > 1)
360 usage();
361 if (argc == 1)
362 host = argv[0];
363 else
364 host = "127.0.0.1";
365
366 if ((target_addr = inet_addr(host)) != -1) {
367 hp = &bogus;
368 hp->h_length = sizeof(target_addr);
369 hp->h_addr_list = (char **)malloc(2 * sizeof(char *));
370 if (hp->h_addr_list == NULL)
371 logit(LOG_ERR, errno, "malloc");
372 hp->h_addr_list[0] = malloc(hp->h_length);
373 if (hp->h_addr_list[0] == NULL)
374 logit(LOG_ERR, errno, "malloc");
375 memcpy(hp->h_addr_list[0], &target_addr, sizeof(hp->h_addr_list[0]));
376 hp->h_addr_list[1] = NULL;
377 } else
378 hp = gethostbyname(host);
379
380 if (hp == NULL || hp->h_length != sizeof(target_addr)) {
381 fprintf(stderr, "mrinfo: %s: no such host\n", argv[0]);
382 exit(1);
383 }
384 if (debug)
385 fprintf(stderr, "Debug level %u\n", debug);
386
387 /* Check all addresses; mrouters often have unreachable interfaces */
388 for (curaddr = 0; hp->h_addr_list[curaddr] != NULL; curaddr++) {
389 memcpy(&target_addr, hp->h_addr_list[curaddr], sizeof(target_addr));
390 { /* Find a good local address for us. */
391 int udp;
392 struct sockaddr_in addr;
393 int addrlen = sizeof(addr);
394
395 memset(&addr, 0, sizeof(addr));
396 addr.sin_family = AF_INET;
397 #if (defined(BSD) && (BSD >= 199103))
398 addr.sin_len = sizeof addr;
399 #endif
400 addr.sin_addr.s_addr = target_addr;
401 addr.sin_port = htons(2000); /* any port over 1024 will
402 * do... */
403 if ((udp = socket(AF_INET, SOCK_DGRAM, 0)) < 0
404 || connect(udp, (struct sockaddr *) & addr, sizeof(addr)) < 0
405 || getsockname(udp, (struct sockaddr *) & addr, &addrlen) < 0) {
406 perror("Determining local address");
407 exit(1);
408 }
409 close(udp);
410 our_addr = addr.sin_addr.s_addr;
411 }
412
413 tries = 0;
414 trynew = 1;
415 /*
416 * New strategy: send 'ask2' for two timeouts, then fall back
417 * to 'ask', since it's not very likely that we are going to
418 * find someone who only responds to 'ask' these days
419 */
420 ask2(target_addr);
421
422 gettimeofday(&et, 0);
423 et.tv_sec += timeout;
424
425 /* Main receive loop */
426 for (;;) {
427 struct pollfd set[1];
428 struct timeval tv, now;
429 int count, recvlen, dummy = 0;
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 < 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, s1, sizeof(s1)));
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, s1, sizeof(s1)));
517 fprintf(stderr, " instead of %s\n",
518 inet_fmt(target_addr, s1, sizeof(s1)));
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