MRInfo 16 KB
Newer Older
Kevin Bracey's avatar
Kevin Bracey committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70
/*
 * This tool requests configuration info from a multicast router
 * and prints the reply (if any).  Invoke it as:
 *
 *	mrinfo router-name-or-address
 *
 * Written Wed Mar 24 1993 by Van Jacobson (adapted from the
 * multicast mapper written by Pavel Curtis).
 *
 * The lawyers insist we include the following UC copyright notice.
 * The mapper from which this is derived contained a Xerox copyright
 * notice which follows the UC one.  Try not to get depressed noting
 * that the legal gibberish is larger than the program.
 *
 * Copyright (c) 1993 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the Computer Systems
 *	Engineering Group at Lawrence Berkeley Laboratory.
 * 4. Neither the name of the University nor of the Laboratory may be used
 *    to endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ---------------------------------
 * Copyright (c) Xerox Corporation 1992. All rights reserved.
 *
 * License is granted to copy, to use, and to make and to use derivative works
 * for research and evaluation purposes, provided that Xerox is acknowledged
 * in all documentation pertaining to any such copy or derivative work. Xerox
 * grants no other licenses expressed or implied. The Xerox trade name should
 * not be used in any advertising without its written permission.
 *
 * XEROX CORPORATION MAKES NO REPRESENTATIONS CONCERNING EITHER THE
 * MERCHANTABILITY OF THIS SOFTWARE OR THE SUITABILITY OF THIS SOFTWARE FOR
 * ANY PARTICULAR PURPOSE.  The software is provided "as is" without express
 * or implied warranty of any kind.
 *
 * These notices must be retained in any copies of any part of this software.
 */

#ifndef lint
static const char rcsid[] =
    "$Id$";
/*  original rcsid:
    "@(#) Header: mrinfo.c,v 1.6 93/04/08 15:14:16 van Exp (LBL)";
*/
#endif

#include <err.h>
ROOL's avatar
ROOL committed
71
#include <sys/types.h>
Kevin Bracey's avatar
Kevin Bracey committed
72 73 74 75 76 77 78 79 80 81 82
#include <netdb.h>
#include <sys/time.h>
#include "defs.h"
#include <arpa/inet.h>
#ifdef __STDC__
#include <stdarg.h>
#else
#include <varargs.h>
#endif

#ifdef __riscos
83
char *__progname = "mrinfo";
Kevin Bracey's avatar
Kevin Bracey committed
84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146

static void closesockets(void)
{
    if (igmp_socket >= 0) close(igmp_socket);
}
#endif

#define DEFAULT_TIMEOUT	4	/* How long to wait before retrying requests */
#define DEFAULT_RETRIES 3	/* How many times to ask each router */

u_int32	our_addr, target_addr = 0;	/* in NET order */
int     debug = 0;
int	nflag = 0;
int     retries = DEFAULT_RETRIES;
int     timeout = DEFAULT_TIMEOUT;
int	target_level = 0;
vifi_t  numvifs;		/* to keep loader happy */
				/* (see COPY_TABLES macro called in kern.c) */

char *			inet_name __P((u_int32 addr));
void			ask __P((u_int32 dst));
void			ask2 __P((u_int32 dst));
int			get_number __P((int *var, int deflt, char ***pargv,
					int *pargc));
u_int32			host_addr __P((char *name));
static void		usage __P((void));

/* to shut up -Wstrict-prototypes */
int			main __P((int argc, char *argv[]));


char   *
inet_name(addr)
	u_int32  addr;
{
	struct hostent *e;
	struct in_addr in;

	if (addr == 0)
		return "local";

	if (nflag ||
	    (e = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET)) == NULL) {
		in.s_addr = addr;
		return (inet_ntoa(in));
	}
	return (e->h_name);
}

/*
 * Log errors and other messages to stderr, according to the severity of the
 * message and the current debug level.  For errors of severity LOG_ERR or
 * worse, terminate the program.
 */
#ifdef __STDC__
void
log(int severity, int syserr, char *format, ...)
#else
void
log(severity, syserr, format, va_alist)
	int     severity, syserr;
	char   *format;
	va_dcl
Robert Sprowson's avatar
Robert Sprowson committed
147
#endif
Kevin Bracey's avatar
Kevin Bracey committed
148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167
{
	va_list ap;
	char    fmt[100];

	switch (debug) {
	case 0:
		if (severity > LOG_WARNING)
			return;
	case 1:
		if (severity > LOG_NOTICE)
			return;
	case 2:
		if (severity > LOG_INFO)
			return;
	default:
		fmt[0] = '\0';
		if (severity == LOG_WARNING)
			strcpy(fmt, "warning - ");
		strncat(fmt, format, sizeof(fmt)-strlen(fmt));
		fmt[sizeof(fmt)-1]='\0';
Robert Sprowson's avatar
Robert Sprowson committed
168 169 170 171 172
#ifdef __STDC__
		va_start(ap, format);
#else
		va_start(ap);
#endif
Kevin Bracey's avatar
Kevin Bracey committed
173
		vfprintf(stderr, fmt, ap);
Robert Sprowson's avatar
Robert Sprowson committed
174
		va_end(ap);
Kevin Bracey's avatar
Kevin Bracey committed
175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335
		if (syserr == 0)
			fprintf(stderr, "\n");
#ifdef __riscos
		else if (syserr == errno)
			fprintf(stderr, ": %s\n", _inet_err());
#else
		else if (syserr < sys_nerr)
			fprintf(stderr, ": %s\n", sys_errlist[syserr]);
#endif
		else
			fprintf(stderr, ": errno %d\n", syserr);
	}

	if (severity <= LOG_ERR)
		exit(1);
}

/*
 * Send a neighbors-list request.
 */
void
ask(dst)
	u_int32  dst;
{
	send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS,
			htonl(MROUTED_LEVEL), 0);
}

void
ask2(dst)
	u_int32  dst;
{
	send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS2,
			htonl(MROUTED_LEVEL), 0);
}

/*
 * Process an incoming neighbor-list message.
 */
void
accept_neighbors(src, dst, p, datalen, level)
	u_int32	src, dst, level;
	u_char	*p;
	int     datalen;
{
	u_char *ep = p + datalen;
#define GET_ADDR(a) (a = ((u_int32)*p++ << 24), a += ((u_int32)*p++ << 16),\
		     a += ((u_int32)*p++ << 8), a += *p++)

	printf("%s (%s):\n", inet_fmt(src, s1), inet_name(src));
	while (p < ep) {
		register u_int32 laddr;
		register u_char metric;
		register u_char thresh;
		register int ncount;

		GET_ADDR(laddr);
		laddr = htonl(laddr);
		metric = *p++;
		thresh = *p++;
		ncount = *p++;
		while (--ncount >= 0) {
			register u_int32 neighbor;
			GET_ADDR(neighbor);
			neighbor = htonl(neighbor);
			printf("  %s -> ", inet_fmt(laddr, s1));
			printf("%s (%s) [%d/%d]\n", inet_fmt(neighbor, s1),
			       inet_name(neighbor), metric, thresh);
		}
	}
}

void
accept_neighbors2(src, dst, p, datalen, level)
	u_int32	src, dst, level;
	u_char	*p;
	int     datalen;
{
	u_char *ep = p + datalen;
	u_int broken_cisco = ((level & 0xffff) == 0x020a); /* 10.2 */
	/* well, only possibly_broken_cisco, but that's too long to type. */
	u_int majvers = level & 0xff;
	u_int minvers = (level >> 8) & 0xff;

	printf("%s (%s) [", inet_fmt(src, s1), inet_name(src));
	if (majvers == 3 && minvers == 0xff)
		printf("DVMRPv3 compliant");
	else
		printf("version %d.%d", majvers, minvers);
	printf ("]:\n");

	while (p < ep) {
		register u_char metric;
		register u_char thresh;
		register u_char flags;
		register int ncount;
		register u_int32 laddr = *(u_int32*)p;

		p += 4;
		metric = *p++;
		thresh = *p++;
		flags = *p++;
		ncount = *p++;
		if (broken_cisco && ncount == 0)	/* dumb Ciscos */
			ncount = 1;
		if (broken_cisco && ncount > 15)	/* dumb Ciscos */
			ncount = ncount & 0xf;
		while (--ncount >= 0 && p < ep) {
			register u_int32 neighbor = *(u_int32*)p;
			p += 4;
			printf("  %s -> ", inet_fmt(laddr, s1));
			printf("%s (%s) [%d/%d", inet_fmt(neighbor, s1),
			       inet_name(neighbor), metric, thresh);
			if (flags & DVMRP_NF_TUNNEL)
				printf("/tunnel");
			if (flags & DVMRP_NF_SRCRT)
				printf("/srcrt");
			if (flags & DVMRP_NF_PIM)
				printf("/pim");
			if (flags & DVMRP_NF_QUERIER)
				printf("/querier");
			if (flags & DVMRP_NF_DISABLED)
				printf("/disabled");
			if (flags & DVMRP_NF_DOWN)
				printf("/down");
			if (flags & DVMRP_NF_LEAF)
				printf("/leaf");
			printf("]\n");
		}
	}
}

int
get_number(var, deflt, pargv, pargc)
	int    *var, *pargc, deflt;
	char ***pargv;
{
	if ((*pargv)[0][2] == '\0') {	/* Get the value from the next
					 * argument */
		if (*pargc > 1 && isdigit((*pargv)[1][0])) {
			(*pargv)++, (*pargc)--;
			*var = atoi((*pargv)[0]);
			return 1;
		} else if (deflt >= 0) {
			*var = deflt;
			return 1;
		} else
			return 0;
	} else {		/* Get value from the rest of this argument */
		if (isdigit((*pargv)[0][2])) {
			*var = atoi((*pargv)[0] + 2);
			return 1;
		} else {
			return 0;
		}
	}
}

static void
usage()
{
336 337 338 339 340
	fprintf(stderr,"Usage:   mrinfo [-n] [-t timeout] [-r retries] [router]\n");
	fprintf(stderr,"         displays configuration info for a multicast router\n");
	fprintf(stderr,"Options: -n  do not attempt to lookup names using DNS\n");
	fprintf(stderr,"         -t  set the retry timeout (default 4s)\n");
	fprintf(stderr,"         -r  set the neighbour retry limit (default 3)\n");
Kevin Bracey's avatar
Kevin Bracey committed
341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663
	exit(1);
}

int
main(argc, argv)
	int     argc;
	char   *argv[];
{
	int tries;
	int trynew;
	struct timeval et;
	struct hostent *hp;
	struct hostent bogus;
	char *host;
	int curaddr;

#ifdef __riscos
	atexit(closesockets);
#else
	if (geteuid() != 0)
		errx(1, "must be root");
#endif

	init_igmp();
	setuid(getuid());

	setlinebuf(stderr);

	argv++, argc--;
	while (argc > 0 && argv[0][0] == '-') {
		switch (argv[0][1]) {
		case 'd':
			if (!get_number(&debug, DEFAULT_DEBUG, &argv, &argc))
				usage();
			break;
		case 'n':
			++nflag;
			break;
		case 'r':
			if (!get_number(&retries, -1, &argv, &argc))
				usage();
			break;
		case 't':
			if (!get_number(&timeout, -1, &argv, &argc))
				usage();
			break;
		default:
			usage();
		}
		argv++, argc--;
	}
	if (argc > 1)
		usage();
	if (argc == 1)
		host = argv[0];
	else
		host = "127.0.0.1";

	if ((target_addr = inet_addr(host)) != -1) {
		hp = &bogus;
		hp->h_length = sizeof(target_addr);
		hp->h_addr_list = (char **)malloc(2 * sizeof(char *));
		hp->h_addr_list[0] = malloc(hp->h_length);
		memcpy(hp->h_addr_list[0], &target_addr, hp->h_length);
		hp->h_addr_list[1] = 0;
	} else
		hp = gethostbyname(host);

	if (hp == NULL || hp->h_length != sizeof(target_addr))
		errx(1, "%s: no such host", argv[0]);
	if (debug)
		fprintf(stderr, "Debug level %u\n", debug);

	/* Check all addresses; mrouters often have unreachable interfaces */
	for (curaddr = 0; hp->h_addr_list[curaddr] != NULL; curaddr++) {
	    memcpy(&target_addr, hp->h_addr_list[curaddr], hp->h_length);
	    {			/* Find a good local address for us. */
		int     udp;
		struct sockaddr_in addr;
		int     addrlen = sizeof(addr);

		addr.sin_family = AF_INET;
#ifdef HAVE_SA_LEN
		addr.sin_len = sizeof addr;
#endif
		addr.sin_addr.s_addr = target_addr;
		addr.sin_port = htons(2000);	/* any port over 1024 will
						 * do... */
		if ((udp = socket(AF_INET, SOCK_DGRAM, 0)) < 0
		|| connect(udp, (struct sockaddr *) & addr, sizeof(addr)) < 0
		|| getsockname(udp, (struct sockaddr *) & addr, &addrlen) < 0)
#ifdef __riscos
		{
			if (udp >= 0) close(udp);
			err(-1, "determining local address");
		}
#else
			err(-1, "determining local address");
#endif
		close(udp);
		our_addr = addr.sin_addr.s_addr;
	    }

	    tries = 0;
	    trynew = 1;
	    /*
	     * New strategy: send 'ask2' for two timeouts, then fall back
	     * to 'ask', since it's not very likely that we are going to
	     * find someone who only responds to 'ask' these days
	     */
	    ask2(target_addr);

	    gettimeofday(&et, 0);
	    et.tv_sec += timeout;

	    /* Main receive loop */
	    for (;;) {
		fd_set  fds;
		struct timeval tv, now;
		int     count, recvlen, dummy = 0;
		register u_int32 src, dst, group;
		struct ip *ip;
		struct igmp *igmp;
		int     ipdatalen, iphdrlen, igmpdatalen;

		FD_ZERO(&fds);
		FD_SET(igmp_socket, &fds);

		gettimeofday(&now, 0);
		tv.tv_sec = et.tv_sec - now.tv_sec;
		tv.tv_usec = et.tv_usec - now.tv_usec;

		if (tv.tv_usec < 0) {
			tv.tv_usec += 1000000L;
			--tv.tv_sec;
		}
		if (tv.tv_sec < 0)
			tv.tv_sec = tv.tv_usec = 0;

		count = select(igmp_socket + 1, &fds, 0, 0, &tv);

		if (count < 0) {
			if (errno != EINTR)
				warn("select");
			continue;
		} else if (count == 0) {
			log(LOG_DEBUG, 0, "Timed out receiving neighbor lists");
			if (++tries > retries)
				break;
			/* If we've tried ASK_NEIGHBORS2 twice with
			 * no response, fall back to ASK_NEIGHBORS
			 */
			if (tries == 2 && target_level == 0)
				trynew = 0;
			if (target_level == 0 && trynew == 0)
				ask(target_addr);
			else
				ask2(target_addr);
			gettimeofday(&et, 0);
			et.tv_sec += timeout;
			continue;
		}
		recvlen = recvfrom(igmp_socket, recv_buf, RECV_BUF_SIZE,
				   0, NULL, &dummy);
		if (recvlen <= 0) {
			if (recvlen && errno != EINTR)
				warn("recvfrom");
			continue;
		}

		if (recvlen < sizeof(struct ip)) {
			log(LOG_WARNING, 0,
			    "packet too short (%u bytes) for IP header",
			    recvlen);
			continue;
		}
		ip = (struct ip *) recv_buf;
		if (ip->ip_p == 0)
			continue;	/* Request to install cache entry */
		src = ip->ip_src.s_addr;
		dst = ip->ip_dst.s_addr;
		iphdrlen = ip->ip_hl << 2;
#ifdef RAW_INPUT_IS_RAW
		ipdatalen = ntohs(ip->ip_len) - iphdrlen;
#else
		ipdatalen = ip->ip_len;
#endif
		if (iphdrlen + ipdatalen != recvlen) {
		    log(LOG_WARNING, 0,
		      "packet shorter (%u bytes) than hdr+data length (%u+%u)",
		      recvlen, iphdrlen, ipdatalen);
		    continue;
		}
		igmp = (struct igmp *) (recv_buf + iphdrlen);
		group = igmp->igmp_group.s_addr;
		igmpdatalen = ipdatalen - IGMP_MINLEN;
		if (igmpdatalen < 0) {
		    log(LOG_WARNING, 0,
			"IP data field too short (%u bytes) for IGMP, from %s",
			ipdatalen, inet_fmt(src, s1));
		    continue;
		}
		if (igmp->igmp_type != IGMP_DVMRP)
			continue;

		switch (igmp->igmp_code) {
		case DVMRP_NEIGHBORS:
		case DVMRP_NEIGHBORS2:
			if (src != target_addr) {
				warnx("got reply from %s instead of %s",
				inet_fmt(src, s1), inet_fmt(target_addr, s2));
				/*continue;*/
			}
			break;
		default:
			continue;	/* ignore all other DVMRP messages */
		}

		switch (igmp->igmp_code) {

		case DVMRP_NEIGHBORS:
			if (group) {
				/* knows about DVMRP_NEIGHBORS2 msg */
				if (target_level == 0) {
					target_level = ntohl(group);
					ask2(target_addr);
				}
			} else {
				accept_neighbors(src, dst, (u_char *)(igmp + 1),
						 igmpdatalen, ntohl(group));
				exit(0);
			}
			break;

		case DVMRP_NEIGHBORS2:
			accept_neighbors2(src, dst, (u_char *)(igmp + 1),
					  igmpdatalen, ntohl(group));
			exit(0);
		}
	    }
	}
	exit(1);
}

/* dummies */
void accept_probe(src, dst, p, datalen, level)
	u_int32 src, dst, level;
	char *p;
	int datalen;
{
}
void accept_group_report(src, dst, group, r_type)
	u_int32 src, dst, group;
	int r_type;
{
}
void accept_neighbor_request2(src, dst)
	u_int32 src, dst;
{
}
void accept_report(src, dst, p, datalen, level)
	u_int32 src, dst, level;
	char *p;
	int datalen;
{
}
void accept_neighbor_request(src, dst)
	u_int32 src, dst;
{
}
void accept_prune(src, dst, p, datalen)
	u_int32 src, dst;
	char *p;
	int datalen;
{
}
void accept_graft(src, dst, p, datalen)
	u_int32 src, dst;
	char *p;
	int datalen;
{
}
void accept_g_ack(src, dst, p, datalen)
	u_int32 src, dst;
	char *p;
	int datalen;
{
}
void add_table_entry(origin, mcastgrp)
	u_int32 origin, mcastgrp;
{
}
void check_vif_state()
{
}
void accept_leave_message(src, dst, group)
	u_int32 src, dst, group;
{
}
void accept_mtrace(src, dst, group, data, no, datalen)
	u_int32 src, dst, group;
	char *data;
	u_int no;
	int datalen;
{
}
void accept_membership_query(src, dst, group, tmo)
	u_int32 src, dst, group;
	int tmo;
{
}
void accept_info_request(src, dst, p, datalen)
	u_int32 src, dst;
	u_char *p;
	int datalen;
{
}
void accept_info_reply(src, dst, p, datalen)
	u_int32 src, dst;
	u_char *p;
	int datalen;
{
}