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) 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 <string.h> 78 #include <netdb.h> 79 #include <sys/time.h> 80 #include "defs.h" 81 #include <arpa/inet.h> 82 #include <stdarg.h> 83 #include <poll.h> 84 #include <limits.h> 85 #include <err.h> 86 87 #define DEFAULT_TIMEOUT 4 /* How long to wait before retrying requests */ 88 #define DEFAULT_RETRIES 3 /* How many times to ask each router */ 89 90 u_int32_t our_addr, target_addr = 0; /* in NET order */ 91 int debug = 0; 92 int nflag = 0; 93 int retries = DEFAULT_RETRIES; 94 int timeout = DEFAULT_TIMEOUT; 95 int target_level = 0; 96 vifi_t numvifs; /* to keep loader happy */ 97 /* (see COPY_TABLES macro called in kern.c) */ 98 99 char *inet_name(u_int32_t addr); 100 void ask(u_int32_t dst); 101 void ask2(u_int32_t dst); 102 void usage(void); 103 104 char * 105 inet_name(u_int32_t addr) 106 { 107 struct hostent *e; 108 struct in_addr in; 109 110 if (addr == 0) 111 return "local"; 112 113 if (nflag || 114 (e = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET)) == NULL) { 115 in.s_addr = addr; 116 return (inet_ntoa(in)); 117 } 118 return (e->h_name); 119 } 120 121 /* 122 * Log errors and other messages to stderr, according to the severity of the 123 * message and the current debug level. For errors of severity LOG_ERR or 124 * worse, terminate the program. 125 */ 126 void 127 logit(int severity, int syserr, char *format, ...) 128 { 129 va_list ap; 130 131 switch (debug) { 132 case 0: 133 if (severity > LOG_WARNING) 134 return; 135 case 1: 136 if (severity > LOG_NOTICE) 137 return; 138 case 2: 139 if (severity > LOG_INFO) 140 return; 141 default: 142 if (severity == LOG_WARNING) 143 fprintf(stderr, "warning - "); 144 va_start(ap, format); 145 vfprintf(stderr, format, ap); 146 va_end(ap); 147 if (syserr == 0) 148 fputc('\n', stderr); 149 else if (syserr < sys_nerr) 150 fprintf(stderr, ": %s\n", sys_errlist[syserr]); 151 else 152 fprintf(stderr, ": errno %d\n", syserr); 153 } 154 155 if (severity <= LOG_ERR) 156 exit(1); 157 } 158 159 /* 160 * Send a neighbors-list request. 161 */ 162 void 163 ask(u_int32_t dst) 164 { 165 send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS, 166 htonl(MROUTED_LEVEL), 0); 167 } 168 169 void 170 ask2(u_int32_t dst) 171 { 172 send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS2, 173 htonl(MROUTED_LEVEL), 0); 174 } 175 176 /* 177 * Process an incoming neighbor-list message. 178 */ 179 void 180 accept_neighbors(u_int32_t src, u_int32_t dst, u_char *p, int datalen, 181 u_int32_t level) 182 { 183 u_char *ep = p + datalen; 184 185 #define GET_ADDR(a) (a = ((u_int32_t)*p++ << 24), a += ((u_int32_t)*p++ << 16),\ 186 a += ((u_int32_t)*p++ << 8), a += *p++) 187 188 printf("%s (%s):\n", inet_fmt(src, s1), inet_name(src)); 189 while (p < ep) { 190 u_char metric, thresh; 191 u_int32_t laddr; 192 int ncount; 193 194 GET_ADDR(laddr); 195 laddr = htonl(laddr); 196 metric = *p++; 197 thresh = *p++; 198 ncount = *p++; 199 while (--ncount >= 0) { 200 u_int32_t neighbor; 201 202 GET_ADDR(neighbor); 203 neighbor = htonl(neighbor); 204 printf(" %s -> ", inet_fmt(laddr, s1)); 205 printf("%s (%s) [%d/%d]\n", inet_fmt(neighbor, s1), 206 inet_name(neighbor), metric, thresh); 207 } 208 } 209 } 210 211 void 212 accept_neighbors2(u_int32_t src, u_int32_t dst, u_char *p, int datalen, 213 u_int32_t level) 214 { 215 u_char *ep = p + datalen; 216 u_int broken_cisco = ((level & 0xffff) == 0x020a); /* 10.2 */ 217 /* well, only possibly_broken_cisco, but that's too long to type. */ 218 219 printf("%s (%s) [version %d.%d", inet_fmt(src, s1), inet_name(src), 220 level & 0xff, (level >> 8) & 0xff); 221 if ((level >> 16) & NF_LEAF) 222 printf (",leaf"); 223 if ((level >> 16) & NF_PRUNE) 224 printf (",prune"); 225 if ((level >> 16) & NF_GENID) 226 printf (",genid"); 227 if ((level >> 16) & NF_MTRACE) 228 printf (",mtrace"); 229 printf ("]:\n"); 230 231 while (p < ep) { 232 u_char metric, thresh, flags; 233 u_int32_t laddr = *(u_int32_t*)p; 234 int ncount; 235 236 p += 4; 237 metric = *p++; 238 thresh = *p++; 239 flags = *p++; 240 ncount = *p++; 241 if (broken_cisco && ncount == 0) /* dumb Ciscos */ 242 ncount = 1; 243 if (broken_cisco && ncount > 15) /* dumb Ciscos */ 244 ncount = ncount & 0xf; 245 while (--ncount >= 0 && p < ep) { 246 u_int32_t neighbor = *(u_int32_t*)p; 247 p += 4; 248 printf(" %s -> ", inet_fmt(laddr, s1)); 249 printf("%s (%s) [%d/%d", inet_fmt(neighbor, s1), 250 inet_name(neighbor), metric, thresh); 251 if (flags & DVMRP_NF_TUNNEL) 252 printf("/tunnel"); 253 if (flags & DVMRP_NF_SRCRT) 254 printf("/srcrt"); 255 if (flags & DVMRP_NF_PIM) 256 printf("/pim"); 257 if (flags & DVMRP_NF_QUERIER) 258 printf("/querier"); 259 if (flags & DVMRP_NF_DISABLED) 260 printf("/disabled"); 261 if (flags & DVMRP_NF_DOWN) 262 printf("/down"); 263 if (flags & DVMRP_NF_LEAF) 264 printf("/leaf"); 265 printf("]\n"); 266 } 267 } 268 } 269 270 void 271 usage() 272 { 273 fprintf(stderr, 274 "Usage: mrinfo [-d[debug_level]] [-n] [-t timeout] [-r retries] [router]\n"); 275 exit(1); 276 } 277 278 int 279 main(int argc, char *argv[]) 280 { 281 int tries, trynew, curaddr, udp, ch; 282 struct hostent *hp, bogus; 283 struct sockaddr_in addr; 284 socklen_t addrlen; 285 struct timeval et; 286 char *host; 287 uid_t uid; 288 const char *errstr; 289 290 if (geteuid() != 0) { 291 fprintf(stderr, "mrinfo: must be root\n"); 292 exit(1); 293 } 294 295 init_igmp(); 296 297 uid = getuid(); 298 if (setresuid(uid, uid, uid) == -1) 299 err(1, "setresuid"); 300 301 setvbuf(stderr, NULL, _IOLBF, 0); 302 303 while ((ch = getopt(argc, argv, "d::nr:t:")) != -1) { 304 switch (ch) { 305 case 'd': 306 if (!optarg) 307 debug = DEFAULT_DEBUG; 308 else { 309 debug = strtonum(optarg, 0, 3, &errstr); 310 if (errstr) { 311 warnx("debug level %s", errstr); 312 debug = DEFAULT_DEBUG; 313 } 314 } 315 break; 316 case 'n': 317 ++nflag; 318 break; 319 case 'r': 320 retries = strtonum(optarg, 0, INT_MAX, &errstr); 321 if (errstr) { 322 warnx("retries %s", errstr); 323 usage(); 324 } 325 break; 326 case 't': 327 timeout = strtonum(optarg, 0, INT_MAX, &errstr); 328 if (errstr) { 329 warnx("timeout %s", errstr); 330 usage(); 331 } 332 break; 333 default: 334 usage(); 335 } 336 } 337 argc -= optind; 338 argv += optind; 339 340 if (argc > 1) 341 usage(); 342 if (argc == 1) 343 host = argv[0]; 344 else 345 host = "127.0.0.1"; 346 347 if ((target_addr = inet_addr(host)) != -1) { 348 hp = &bogus; 349 hp->h_length = sizeof(target_addr); 350 if (!(hp->h_addr_list = calloc(2, sizeof(char *)))) 351 err(1, "can't allocate memory"); 352 if (!(hp->h_addr_list[0] = malloc(hp->h_length))) 353 err(1, "can't allocate memory"); 354 memcpy(hp->h_addr_list[0], &target_addr, hp->h_length); 355 hp->h_addr_list[1] = 0; 356 } else 357 hp = gethostbyname(host); 358 359 if (hp == NULL || hp->h_length != sizeof(target_addr)) { 360 fprintf(stderr, "mrinfo: %s: no such host\n", argv[0]); 361 exit(1); 362 } 363 if (debug) 364 fprintf(stderr, "Debug level %u\n", debug); 365 366 /* Check all addresses; mrouters often have unreachable interfaces */ 367 for (curaddr = 0; hp->h_addr_list[curaddr] != NULL; curaddr++) { 368 memcpy(&target_addr, hp->h_addr_list[curaddr], hp->h_length); 369 /* Find a good local address for us. */ 370 addrlen = sizeof(addr); 371 memset(&addr, 0, sizeof addr); 372 addr.sin_family = AF_INET; 373 addr.sin_len = sizeof addr; 374 addr.sin_addr.s_addr = target_addr; 375 addr.sin_port = htons(2000); /* any port over 1024 will 376 * do... */ 377 if ((udp = socket(AF_INET, SOCK_DGRAM, 0)) == -1 || 378 connect(udp, (struct sockaddr *) & addr, sizeof(addr)) == -1 || 379 getsockname(udp, (struct sockaddr *) & addr, &addrlen) == -1) { 380 perror("Determining local address"); 381 exit(1); 382 } 383 close(udp); 384 our_addr = addr.sin_addr.s_addr; 385 386 tries = 0; 387 trynew = 1; 388 /* 389 * New strategy: send 'ask2' for two timeouts, then fall back 390 * to 'ask', since it's not very likely that we are going to 391 * find someone who only responds to 'ask' these days 392 */ 393 ask2(target_addr); 394 395 gettimeofday(&et, 0); 396 et.tv_sec += timeout; 397 398 /* Main receive loop */ 399 for (;;) { 400 int count, recvlen, ipdatalen, iphdrlen, igmpdatalen; 401 u_int32_t src, dst, group; 402 struct timeval tv, now; 403 socklen_t dummy = 0; 404 struct igmp *igmp; 405 struct ip *ip; 406 struct pollfd pfd[1]; 407 408 pfd[0].fd = igmp_socket; 409 pfd[0].events = POLLIN; 410 411 gettimeofday(&now, 0); 412 tv.tv_sec = et.tv_sec - now.tv_sec; 413 tv.tv_usec = et.tv_usec - now.tv_usec; 414 415 if (tv.tv_usec < 0) { 416 tv.tv_usec += 1000000L; 417 --tv.tv_sec; 418 } 419 if (tv.tv_sec < 0) 420 timerclear(&tv); 421 422 count = poll(pfd, 1, tv.tv_sec * 1000); 423 424 if (count == -1) { 425 if (errno != EINTR) 426 perror("select"); 427 continue; 428 } else if (count == 0) { 429 logit(LOG_DEBUG, 0, 430 "Timed out receiving neighbor lists"); 431 if (++tries > retries) 432 break; 433 /* If we've tried ASK_NEIGHBORS2 twice with 434 * no response, fall back to ASK_NEIGHBORS 435 */ 436 if (tries == 2 && target_level == 0) 437 trynew = 0; 438 if (target_level == 0 && trynew == 0) 439 ask(target_addr); 440 else 441 ask2(target_addr); 442 gettimeofday(&et, 0); 443 et.tv_sec += timeout; 444 continue; 445 } 446 recvlen = recvfrom(igmp_socket, recv_buf, RECV_BUF_SIZE, 447 0, NULL, &dummy); 448 if (recvlen <= 0) { 449 if (recvlen && errno != EINTR) 450 perror("recvfrom"); 451 continue; 452 } 453 454 if (recvlen < sizeof(struct ip)) { 455 logit(LOG_WARNING, 0, 456 "packet too short (%u bytes) for IP header", 457 recvlen); 458 continue; 459 } 460 ip = (struct ip *) recv_buf; 461 if (ip->ip_p == 0) 462 continue; /* Request to install cache entry */ 463 src = ip->ip_src.s_addr; 464 dst = ip->ip_dst.s_addr; 465 iphdrlen = ip->ip_hl << 2; 466 ipdatalen = ntohs(ip->ip_len) - iphdrlen; 467 if (iphdrlen + ipdatalen != recvlen) { 468 logit(LOG_WARNING, 0, 469 "packet shorter (%u bytes) than " 470 "hdr+data length (%u+%u)", 471 recvlen, iphdrlen, ipdatalen); 472 continue; 473 } 474 igmp = (struct igmp *) (recv_buf + iphdrlen); 475 group = igmp->igmp_group.s_addr; 476 igmpdatalen = ipdatalen - IGMP_MINLEN; 477 if (igmpdatalen < 0) { 478 logit(LOG_WARNING, 0, 479 "IP data field too short (%u bytes) " 480 "for IGMP, from %s", 481 ipdatalen, inet_fmt(src, s1)); 482 continue; 483 } 484 if (igmp->igmp_type != IGMP_DVMRP) 485 continue; 486 487 switch (igmp->igmp_code) { 488 case DVMRP_NEIGHBORS: 489 case DVMRP_NEIGHBORS2: 490 if (src != target_addr) { 491 fprintf(stderr, "mrinfo: got reply from %s", 492 inet_fmt(src, s1)); 493 fprintf(stderr, " instead of %s\n", 494 inet_fmt(target_addr, s1)); 495 /*continue;*/ 496 } 497 break; 498 default: 499 continue; /* ignore all other DVMRP messages */ 500 } 501 502 switch (igmp->igmp_code) { 503 case DVMRP_NEIGHBORS: 504 if (group) { 505 /* knows about DVMRP_NEIGHBORS2 msg */ 506 if (target_level == 0) { 507 target_level = ntohl(group); 508 ask2(target_addr); 509 } 510 } else { 511 accept_neighbors(src, dst, (u_char *)(igmp + 1), 512 igmpdatalen, ntohl(group)); 513 exit(0); 514 } 515 break; 516 case DVMRP_NEIGHBORS2: 517 accept_neighbors2(src, dst, (u_char *)(igmp + 1), 518 igmpdatalen, ntohl(group)); 519 exit(0); 520 } 521 } 522 } 523 exit(1); 524 } 525 526 /* dummies */ 527 void 528 accept_probe(u_int32_t src, u_int32_t dst, char *p, int datalen, 529 u_int32_t level) 530 { 531 } 532 533 void 534 accept_group_report(u_int32_t src, u_int32_t dst, u_int32_t group, int r_type) 535 { 536 } 537 538 void 539 accept_neighbor_request2(u_int32_t src, u_int32_t dst) 540 { 541 } 542 543 void 544 accept_report(u_int32_t src, u_int32_t dst, char *p, int datalen, 545 u_int32_t level) 546 { 547 } 548 549 void 550 accept_neighbor_request(u_int32_t src, u_int32_t dst) 551 { 552 } 553 554 void 555 accept_prune(u_int32_t src, u_int32_t dst, char *p, int datalen) 556 { 557 } 558 559 void 560 accept_graft(u_int32_t src, u_int32_t dst, char *p, int datalen) 561 { 562 } 563 564 void 565 accept_g_ack(u_int32_t src, u_int32_t dst, char *p, int datalen) 566 { 567 } 568 569 void 570 add_table_entry(u_int32_t origin, u_int32_t mcastgrp) 571 { 572 } 573 574 void 575 check_vif_state(void) 576 { 577 } 578 579 void 580 accept_leave_message(u_int32_t src, u_int32_t dst, u_int32_t group) 581 { 582 } 583 584 void 585 accept_mtrace(u_int32_t src, u_int32_t dst, u_int32_t group, char *data, 586 u_int no, int datalen) 587 { 588 } 589 590 void 591 accept_membership_query(u_int32_t src, u_int32_t dst, u_int32_t group, int tmo) 592 { 593 } 594 595 void 596 accept_info_request(u_int32_t src, u_int32_t dst, u_char *p, int datalen) 597 { 598 } 599 600 void 601 accept_info_reply(u_int32_t src, u_int32_t dst, u_char *p, int datalen) 602 { 603 } 604