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mrinfo.c revision 1.7.10.1
      1 /*	$NetBSD: mrinfo.c,v 1.7.10.1 2000/10/17 19:50:24 tv 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 #include <sys/cdefs.h>
     65 #ifndef lint
     66 #if 0
     67 static char rcsid[] =
     68     "@(#) Header: mrinfo.c,v 1.6 93/04/08 15:14:16 van Exp (LBL)";
     69 #else
     70 __RCSID("$NetBSD: mrinfo.c,v 1.7.10.1 2000/10/17 19:50:24 tv Exp $");
     71 #endif
     72 #endif
     73 
     74 #include <string.h>
     75 #include <netdb.h>
     76 #include <sys/time.h>
     77 #include "defs.h"
     78 #include <arpa/inet.h>
     79 #ifdef __STDC__
     80 #include <stdarg.h>
     81 #else
     82 #include <varargs.h>
     83 #endif
     84 
     85 #define DEFAULT_TIMEOUT	4	/* How long to wait before retrying requests */
     86 #define DEFAULT_RETRIES 3	/* How many times to ask each router */
     87 
     88 u_int32_t	our_addr, target_addr = 0;	/* in NET order */
     89 int     debug = 0;
     90 int	nflag = 0;
     91 int     retries = DEFAULT_RETRIES;
     92 int     timeout = DEFAULT_TIMEOUT;
     93 int	target_level = 0;
     94 vifi_t  numvifs;		/* to keep loader happy */
     95 				/* (see COPY_TABLES macro called in kern.c) */
     96 
     97 char *			inet_name __P((u_int32_t addr));
     98 void			ask __P((u_int32_t dst));
     99 void			ask2 __P((u_int32_t dst));
    100 int			get_number __P((int *var, int deflt, char ***pargv,
    101 					int *pargc));
    102 u_int32_t			host_addr __P((char *name));
    103 void			usage __P((void));
    104 
    105 /* to shut up -Wstrict-prototypes */
    106 int			main __P((int argc, char *argv[]));
    107 
    108 
    109 char   *
    110 inet_name(addr)
    111 	u_int32_t  addr;
    112 {
    113 	struct hostent *e;
    114 	struct in_addr in;
    115 
    116 	if (addr == 0)
    117 		return "local";
    118 
    119 	if (nflag ||
    120 	    (e = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET)) == NULL) {
    121 		in.s_addr = addr;
    122 		return (inet_ntoa(in));
    123 	}
    124 	return (e->h_name);
    125 }
    126 
    127 /*
    128  * Log errors and other messages to stderr, according to the severity of the
    129  * message and the current debug level.  For errors of severity LOG_ERR or
    130  * worse, terminate the program.
    131  */
    132 #ifdef __STDC__
    133 void
    134 log(int severity, int syserr, const char *format, ...)
    135 {
    136 	va_list ap;
    137 	char    fmt[100];
    138 
    139 	va_start(ap, format);
    140 #else
    141 void
    142 log(severity, syserr, format, va_alist)
    143 	int     severity, syserr;
    144 	char   *format;
    145 	va_dcl
    146 {
    147 	va_list ap;
    148 	char    fmt[100];
    149 
    150 	va_start(ap);
    151 #endif
    152 	switch (debug) {
    153 	case 0:
    154 		if (severity > LOG_WARNING)
    155 			return;
    156 	case 1:
    157 		if (severity > LOG_NOTICE)
    158 			return;
    159 	case 2:
    160 		if (severity > LOG_INFO)
    161 			return;
    162 	default:
    163 		fmt[0] = '\0';
    164 		if (severity == LOG_WARNING)
    165 			strcat(fmt, "warning - ");
    166 		strncat(fmt, format, 80);
    167 		format = fmt;
    168 		vfprintf(stderr, format, ap);
    169 		if (syserr == 0)
    170 			fprintf(stderr, "\n");
    171 		else
    172 			fprintf(stderr, ": %s\n", strerror(syserr));
    173 	}
    174 
    175 	if (severity <= LOG_ERR)
    176 		exit(-1);
    177 }
    178 
    179 /*
    180  * Send a neighbors-list request.
    181  */
    182 void
    183 ask(dst)
    184 	u_int32_t  dst;
    185 {
    186 	send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS,
    187 			htonl(MROUTED_LEVEL), 0);
    188 }
    189 
    190 void
    191 ask2(dst)
    192 	u_int32_t  dst;
    193 {
    194 	send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS2,
    195 			htonl(MROUTED_LEVEL), 0);
    196 }
    197 
    198 /*
    199  * Process an incoming neighbor-list message.
    200  */
    201 void
    202 accept_neighbors(src, dst, p, datalen, level)
    203 	u_int32_t	src, dst, level;
    204 	u_char	*p;
    205 	int     datalen;
    206 {
    207 	u_char *ep = p + datalen;
    208 #define GET_ADDR(a) (a = ((u_int32_t)*p++ << 24), a += ((u_int32_t)*p++ << 16),\
    209 		     a += ((u_int32_t)*p++ << 8), a += *p++)
    210 
    211 	printf("%s (%s):\n", inet_fmt(src, s1), inet_name(src));
    212 	while (p < ep) {
    213 		register u_int32_t laddr;
    214 		register u_char metric;
    215 		register u_char thresh;
    216 		register int ncount;
    217 
    218 		GET_ADDR(laddr);
    219 		laddr = htonl(laddr);
    220 		metric = *p++;
    221 		thresh = *p++;
    222 		ncount = *p++;
    223 		while (--ncount >= 0) {
    224 			register u_int32_t neighbor;
    225 			GET_ADDR(neighbor);
    226 			neighbor = htonl(neighbor);
    227 			printf("  %s -> ", inet_fmt(laddr, s1));
    228 			printf("%s (%s) [%d/%d]\n", inet_fmt(neighbor, s1),
    229 			       inet_name(neighbor), metric, thresh);
    230 		}
    231 	}
    232 }
    233 
    234 void
    235 accept_neighbors2(src, dst, p, datalen, level)
    236 	u_int32_t	src, dst, level;
    237 	u_char	*p;
    238 	int     datalen;
    239 {
    240 	u_char *ep = p + datalen;
    241 	u_int broken_cisco = ((level & 0xffff) == 0x020a); /* 10.2 */
    242 	/* well, only possibly_broken_cisco, but that's too long to type. */
    243 
    244 	printf("%s (%s) [version %d.%d", inet_fmt(src, s1), inet_name(src),
    245 	       level & 0xff, (level >> 8) & 0xff);
    246 	if ((level >> 16) & NF_LEAF)   { printf (",leaf"); }
    247 	if ((level >> 16) & NF_PRUNE)  { printf (",prune"); }
    248 	if ((level >> 16) & NF_GENID)  { printf (",genid"); }
    249 	if ((level >> 16) & NF_MTRACE) { printf (",mtrace"); }
    250 	printf ("]:\n");
    251 
    252 	while (p < ep) {
    253 		register u_char metric;
    254 		register u_char thresh;
    255 		register u_char flags;
    256 		register int ncount;
    257 		register u_int32_t laddr = *(u_int32_t*)p;
    258 
    259 		p += 4;
    260 		metric = *p++;
    261 		thresh = *p++;
    262 		flags = *p++;
    263 		ncount = *p++;
    264 		if (broken_cisco && ncount == 0)	/* dumb Ciscos */
    265 			ncount = 1;
    266 		if (broken_cisco && ncount > 15)	/* dumb Ciscos */
    267 			ncount = ncount & 0xf;
    268 		while (--ncount >= 0 && p < ep) {
    269 			register u_int32_t neighbor = *(u_int32_t*)p;
    270 			p += 4;
    271 			printf("  %s -> ", inet_fmt(laddr, s1));
    272 			printf("%s (%s) [%d/%d", inet_fmt(neighbor, s1),
    273 			       inet_name(neighbor), metric, thresh);
    274 			if (flags & DVMRP_NF_TUNNEL)
    275 				printf("/tunnel");
    276 			if (flags & DVMRP_NF_SRCRT)
    277 				printf("/srcrt");
    278 			if (flags & DVMRP_NF_PIM)
    279 				printf("/pim");
    280 			if (flags & DVMRP_NF_QUERIER)
    281 				printf("/querier");
    282 			if (flags & DVMRP_NF_DISABLED)
    283 				printf("/disabled");
    284 			if (flags & DVMRP_NF_DOWN)
    285 				printf("/down");
    286 			if (flags & DVMRP_NF_LEAF)
    287 				printf("/leaf");
    288 			printf("]\n");
    289 		}
    290 	}
    291 }
    292 
    293 int
    294 get_number(var, deflt, pargv, pargc)
    295 	int    *var, *pargc, deflt;
    296 	char ***pargv;
    297 {
    298 	if ((*pargv)[0][2] == '\0') {	/* Get the value from the next
    299 					 * argument */
    300 		if (*pargc > 1 && isdigit((*pargv)[1][0])) {
    301 			(*pargv)++, (*pargc)--;
    302 			*var = atoi((*pargv)[0]);
    303 			return 1;
    304 		} else if (deflt >= 0) {
    305 			*var = deflt;
    306 			return 1;
    307 		} else
    308 			return 0;
    309 	} else {		/* Get value from the rest of this argument */
    310 		if (isdigit((*pargv)[0][2])) {
    311 			*var = atoi((*pargv)[0] + 2);
    312 			return 1;
    313 		} else {
    314 			return 0;
    315 		}
    316 	}
    317 }
    318 
    319 void
    320 usage()
    321 {
    322 	fprintf(stderr,
    323 	    "Usage: mrinfo [-n] [-t timeout] [-r retries] [router]\n");
    324 	exit(1);
    325 }
    326 
    327 int
    328 main(argc, argv)
    329 	int     argc;
    330 	char   *argv[];
    331 {
    332 	int tries;
    333 	int trynew;
    334 	struct timeval et;
    335 	struct hostent *hp;
    336 	struct hostent bogus;
    337 	char *host;
    338 	int curaddr;
    339 
    340 	setlinebuf(stderr);
    341 
    342 	if (geteuid() != 0) {
    343 		fprintf(stderr, "mrinfo: must be root\n");
    344 		exit(1);
    345 	}
    346 	argv++, argc--;
    347 	while (argc > 0 && argv[0][0] == '-') {
    348 		switch (argv[0][1]) {
    349 		case 'd':
    350 			if (!get_number(&debug, DEFAULT_DEBUG, &argv, &argc))
    351 				usage();
    352 			break;
    353 		case 'n':
    354 			++nflag;
    355 			break;
    356 		case 'r':
    357 			if (!get_number(&retries, -1, &argv, &argc))
    358 				usage();
    359 			break;
    360 		case 't':
    361 			if (!get_number(&timeout, -1, &argv, &argc))
    362 				usage();
    363 			break;
    364 		default:
    365 			usage();
    366 		}
    367 		argv++, argc--;
    368 	}
    369 	if (argc > 1)
    370 		usage();
    371 	if (argc == 1)
    372 		host = argv[0];
    373 	else
    374 		host = "127.0.0.1";
    375 
    376 	if ((target_addr = inet_addr(host)) != -1) {
    377 		hp = &bogus;
    378 		hp->h_length = sizeof(target_addr);
    379 		hp->h_addr_list = (char **)malloc(2 * sizeof(char *));
    380 		hp->h_addr_list[0] = malloc(hp->h_length);
    381 		memcpy(hp->h_addr_list[0], &target_addr, sizeof(hp->h_addr_list[0]));
    382 		hp->h_addr_list[1] = 0;
    383 	} else
    384 		hp = gethostbyname(host);
    385 
    386 	if (hp == NULL) {
    387 		fprintf(stderr, "mrinfo: %s: no such host\n", argv[0]);
    388 		exit(1);
    389 	}
    390 	if (debug)
    391 		fprintf(stderr, "Debug level %u\n", debug);
    392 
    393 	init_igmp();
    394 
    395 	/* Check all addresses; mrouters often have unreachable interfaces */
    396 	for (curaddr = 0; hp->h_addr_list[curaddr] != NULL; curaddr++) {
    397 	    memcpy(&target_addr, hp->h_addr_list[curaddr], sizeof(target_addr));
    398 	    {			/* Find a good local address for us. */
    399 		int     udp;
    400 		struct sockaddr_in addr;
    401 		int     addrlen = sizeof(addr);
    402 
    403 		addr.sin_family = AF_INET;
    404 #if (defined(BSD) && (BSD >= 199103))
    405 		addr.sin_len = sizeof addr;
    406 #endif
    407 		addr.sin_addr.s_addr = target_addr;
    408 		addr.sin_port = htons(2000);	/* any port over 1024 will
    409 						 * do... */
    410 		if ((udp = socket(AF_INET, SOCK_DGRAM, 0)) < 0
    411 		|| connect(udp, (struct sockaddr *) & addr, sizeof(addr)) < 0
    412 		    || getsockname(udp, (struct sockaddr *) & addr, &addrlen) < 0) {
    413 			perror("Determining local address");
    414 			exit(-1);
    415 		}
    416 		close(udp);
    417 		our_addr = addr.sin_addr.s_addr;
    418 	    }
    419 
    420 	    tries = 0;
    421 	    trynew = 1;
    422 	    /*
    423 	     * New strategy: send 'ask2' for two timeouts, then fall back
    424 	     * to 'ask', since it's not very likely that we are going to
    425 	     * find someone who only responds to 'ask' these days
    426 	     */
    427 	    ask2(target_addr);
    428 
    429 	    gettimeofday(&et, 0);
    430 	    et.tv_sec += timeout;
    431 
    432 	    /* Main receive loop */
    433 	    for (;;) {
    434 		fd_set  fds;
    435 		struct timeval tv, now;
    436 		int     count, recvlen, dummy = 0;
    437 		register u_int32_t src, dst, group;
    438 		struct ip *ip;
    439 		struct igmp *igmp;
    440 		int     ipdatalen, iphdrlen, igmpdatalen;
    441 
    442 		FD_ZERO(&fds);
    443 		FD_SET(igmp_socket, &fds);
    444 
    445 		gettimeofday(&now, 0);
    446 		tv.tv_sec = et.tv_sec - now.tv_sec;
    447 		tv.tv_usec = et.tv_usec - now.tv_usec;
    448 
    449 		if (tv.tv_usec < 0) {
    450 			tv.tv_usec += 1000000L;
    451 			--tv.tv_sec;
    452 		}
    453 		if (tv.tv_sec < 0)
    454 			tv.tv_sec = tv.tv_usec = 0;
    455 
    456 		count = select(igmp_socket + 1, &fds, 0, 0, &tv);
    457 
    458 		if (count < 0) {
    459 			if (errno != EINTR)
    460 				perror("select");
    461 			continue;
    462 		} else if (count == 0) {
    463 			log(LOG_DEBUG, 0, "Timed out receiving neighbor lists");
    464 			if (++tries > retries)
    465 				break;
    466 			/* If we've tried ASK_NEIGHBORS2 twice with
    467 			 * no response, fall back to ASK_NEIGHBORS
    468 			 */
    469 			if (tries == 2 && target_level == 0)
    470 				trynew = 0;
    471 			if (target_level == 0 && trynew == 0)
    472 				ask(target_addr);
    473 			else
    474 				ask2(target_addr);
    475 			gettimeofday(&et, 0);
    476 			et.tv_sec += timeout;
    477 			continue;
    478 		}
    479 		recvlen = recvfrom(igmp_socket, recv_buf, RECV_BUF_SIZE,
    480 				   0, NULL, &dummy);
    481 		if (recvlen <= 0) {
    482 			if (recvlen && errno != EINTR)
    483 				perror("recvfrom");
    484 			continue;
    485 		}
    486 
    487 		if (recvlen < sizeof(struct ip)) {
    488 			log(LOG_WARNING, 0,
    489 			    "packet too short (%u bytes) for IP header",
    490 			    recvlen);
    491 			continue;
    492 		}
    493 		ip = (struct ip *) recv_buf;
    494 		if (ip->ip_p == 0)
    495 			continue;	/* Request to install cache entry */
    496 		src = ip->ip_src.s_addr;
    497 		dst = ip->ip_dst.s_addr;
    498 		iphdrlen = ip->ip_hl << 2;
    499 		ipdatalen = ip->ip_len;
    500 		if (iphdrlen + ipdatalen != recvlen) {
    501 		    log(LOG_WARNING, 0,
    502 		      "packet shorter (%u bytes) than hdr+data length (%u+%u)",
    503 		      recvlen, iphdrlen, ipdatalen);
    504 		    continue;
    505 		}
    506 		igmp = (struct igmp *) (recv_buf + iphdrlen);
    507 		group = igmp->igmp_group.s_addr;
    508 		igmpdatalen = ipdatalen - IGMP_MINLEN;
    509 		if (igmpdatalen < 0) {
    510 		    log(LOG_WARNING, 0,
    511 			"IP data field too short (%u bytes) for IGMP, from %s",
    512 			ipdatalen, inet_fmt(src, s1));
    513 		    continue;
    514 		}
    515 		if (igmp->igmp_type != IGMP_DVMRP)
    516 			continue;
    517 
    518 		switch (igmp->igmp_code) {
    519 		case DVMRP_NEIGHBORS:
    520 		case DVMRP_NEIGHBORS2:
    521 			if (src != target_addr) {
    522 				fprintf(stderr, "mrinfo: got reply from %s",
    523 					inet_fmt(src, s1));
    524 				fprintf(stderr, " instead of %s\n",
    525 					inet_fmt(target_addr, s1));
    526 				/*continue;*/
    527 			}
    528 			break;
    529 		default:
    530 			continue;	/* ignore all other DVMRP messages */
    531 		}
    532 
    533 		switch (igmp->igmp_code) {
    534 
    535 		case DVMRP_NEIGHBORS:
    536 			if (group) {
    537 				/* knows about DVMRP_NEIGHBORS2 msg */
    538 				if (target_level == 0) {
    539 					target_level = ntohl(group);
    540 					ask2(target_addr);
    541 				}
    542 			} else {
    543 				accept_neighbors(src, dst, (u_char *)(igmp + 1),
    544 						 igmpdatalen, ntohl(group));
    545 				exit(0);
    546 			}
    547 			break;
    548 
    549 		case DVMRP_NEIGHBORS2:
    550 			accept_neighbors2(src, dst, (u_char *)(igmp + 1),
    551 					  igmpdatalen, ntohl(group));
    552 			exit(0);
    553 		}
    554 	    }
    555 	}
    556 	exit(1);
    557 }
    558 
    559 /* dummies */
    560 void accept_probe(src, dst, p, datalen, level)
    561 	u_int32_t src, dst, level;
    562 	char *p;
    563 	int datalen;
    564 {
    565 }
    566 void accept_group_report(src, dst, group, r_type)
    567 	u_int32_t src, dst, group;
    568 	int r_type;
    569 {
    570 }
    571 void accept_neighbor_request2(src, dst)
    572 	u_int32_t src, dst;
    573 {
    574 }
    575 void accept_report(src, dst, p, datalen, level)
    576 	u_int32_t src, dst, level;
    577 	char *p;
    578 	int datalen;
    579 {
    580 }
    581 void accept_neighbor_request(src, dst)
    582 	u_int32_t src, dst;
    583 {
    584 }
    585 void accept_prune(src, dst, p, datalen)
    586 	u_int32_t src, dst;
    587 	char *p;
    588 	int datalen;
    589 {
    590 }
    591 void accept_graft(src, dst, p, datalen)
    592 	u_int32_t src, dst;
    593 	char *p;
    594 	int datalen;
    595 {
    596 }
    597 void accept_g_ack(src, dst, p, datalen)
    598 	u_int32_t src, dst;
    599 	char *p;
    600 	int datalen;
    601 {
    602 }
    603 void add_table_entry(origin, mcastgrp)
    604 	u_int32_t origin, mcastgrp;
    605 {
    606 }
    607 void check_vif_state()
    608 {
    609 }
    610 void accept_leave_message(src, dst, group)
    611 	u_int32_t src, dst, group;
    612 {
    613 }
    614 void accept_mtrace(src, dst, group, data, no, datalen)
    615 	u_int32_t src, dst, group;
    616 	char *data;
    617 	u_int no;
    618 	int datalen;
    619 {
    620 }
    621 void accept_membership_query(src, dst, group, tmo)
    622 	u_int32_t src, dst, group;
    623 	int tmo;
    624 {
    625 }
    626 void accept_info_request(src, dst, p, datalen)
    627 	u_int32_t src, dst;
    628 	u_char *p;
    629 	int datalen;
    630 {
    631 }
    632 void accept_info_reply(src, dst, p, datalen)
    633 	u_int32_t src, dst;
    634 	u_char *p;
    635 	int datalen;
    636 {
    637 }
    638