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 u_int32_t host_addr(char *name); 103 void usage(void); 104 105 char * 106 inet_name(u_int32_t addr) 107 { 108 struct hostent *e; 109 struct in_addr in; 110 111 if (addr == 0) 112 return "local"; 113 114 if (nflag || 115 (e = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET)) == NULL) { 116 in.s_addr = addr; 117 return (inet_ntoa(in)); 118 } 119 return (e->h_name); 120 } 121 122 /* 123 * Log errors and other messages to stderr, according to the severity of the 124 * message and the current debug level. For errors of severity LOG_ERR or 125 * worse, terminate the program. 126 */ 127 void 128 logit(int severity, int syserr, char *format, ...) 129 { 130 va_list ap; 131 132 switch (debug) { 133 case 0: 134 if (severity > LOG_WARNING) 135 return; 136 case 1: 137 if (severity > LOG_NOTICE) 138 return; 139 case 2: 140 if (severity > LOG_INFO) 141 return; 142 default: 143 if (severity == LOG_WARNING) 144 fprintf(stderr, "warning - "); 145 va_start(ap, format); 146 vfprintf(stderr, format, ap); 147 va_end(ap); 148 if (syserr == 0) 149 fputc('\n', stderr); 150 else if (syserr < sys_nerr) 151 fprintf(stderr, ": %s\n", sys_errlist[syserr]); 152 else 153 fprintf(stderr, ": errno %d\n", syserr); 154 } 155 156 if (severity <= LOG_ERR) 157 exit(1); 158 } 159 160 /* 161 * Send a neighbors-list request. 162 */ 163 void 164 ask(u_int32_t dst) 165 { 166 send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS, 167 htonl(MROUTED_LEVEL), 0); 168 } 169 170 void 171 ask2(u_int32_t dst) 172 { 173 send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS2, 174 htonl(MROUTED_LEVEL), 0); 175 } 176 177 /* 178 * Process an incoming neighbor-list message. 179 */ 180 void 181 accept_neighbors(u_int32_t src, u_int32_t dst, u_char *p, int datalen, 182 u_int32_t level) 183 { 184 u_char *ep = p + datalen; 185 186 #define GET_ADDR(a) (a = ((u_int32_t)*p++ << 24), a += ((u_int32_t)*p++ << 16),\ 187 a += ((u_int32_t)*p++ << 8), a += *p++) 188 189 printf("%s (%s):\n", inet_fmt(src, s1), inet_name(src)); 190 while (p < ep) { 191 u_char metric, thresh; 192 u_int32_t laddr; 193 int ncount; 194 195 GET_ADDR(laddr); 196 laddr = htonl(laddr); 197 metric = *p++; 198 thresh = *p++; 199 ncount = *p++; 200 while (--ncount >= 0) { 201 u_int32_t neighbor; 202 203 GET_ADDR(neighbor); 204 neighbor = htonl(neighbor); 205 printf(" %s -> ", inet_fmt(laddr, s1)); 206 printf("%s (%s) [%d/%d]\n", inet_fmt(neighbor, s1), 207 inet_name(neighbor), metric, thresh); 208 } 209 } 210 } 211 212 void 213 accept_neighbors2(u_int32_t src, u_int32_t dst, u_char *p, int datalen, 214 u_int32_t level) 215 { 216 u_char *ep = p + datalen; 217 u_int broken_cisco = ((level & 0xffff) == 0x020a); /* 10.2 */ 218 /* well, only possibly_broken_cisco, but that's too long to type. */ 219 220 printf("%s (%s) [version %d.%d", inet_fmt(src, s1), inet_name(src), 221 level & 0xff, (level >> 8) & 0xff); 222 if ((level >> 16) & NF_LEAF) 223 printf (",leaf"); 224 if ((level >> 16) & NF_PRUNE) 225 printf (",prune"); 226 if ((level >> 16) & NF_GENID) 227 printf (",genid"); 228 if ((level >> 16) & NF_MTRACE) 229 printf (",mtrace"); 230 printf ("]:\n"); 231 232 while (p < ep) { 233 u_char metric, thresh, flags; 234 u_int32_t laddr = *(u_int32_t*)p; 235 int ncount; 236 237 p += 4; 238 metric = *p++; 239 thresh = *p++; 240 flags = *p++; 241 ncount = *p++; 242 if (broken_cisco && ncount == 0) /* dumb Ciscos */ 243 ncount = 1; 244 if (broken_cisco && ncount > 15) /* dumb Ciscos */ 245 ncount = ncount & 0xf; 246 while (--ncount >= 0 && p < ep) { 247 u_int32_t neighbor = *(u_int32_t*)p; 248 p += 4; 249 printf(" %s -> ", inet_fmt(laddr, s1)); 250 printf("%s (%s) [%d/%d", inet_fmt(neighbor, s1), 251 inet_name(neighbor), metric, thresh); 252 if (flags & DVMRP_NF_TUNNEL) 253 printf("/tunnel"); 254 if (flags & DVMRP_NF_SRCRT) 255 printf("/srcrt"); 256 if (flags & DVMRP_NF_PIM) 257 printf("/pim"); 258 if (flags & DVMRP_NF_QUERIER) 259 printf("/querier"); 260 if (flags & DVMRP_NF_DISABLED) 261 printf("/disabled"); 262 if (flags & DVMRP_NF_DOWN) 263 printf("/down"); 264 if (flags & DVMRP_NF_LEAF) 265 printf("/leaf"); 266 printf("]\n"); 267 } 268 } 269 } 270 271 void 272 usage() 273 { 274 fprintf(stderr, 275 "Usage: mrinfo [-d [debug_level]] [-n] [-t timeout] [-r retries] [router]\n"); 276 exit(1); 277 } 278 279 int 280 main(int argc, char *argv[]) 281 { 282 int tries, trynew, curaddr, udp, ch; 283 struct hostent *hp, bogus; 284 struct sockaddr_in addr; 285 socklen_t addrlen; 286 struct timeval et; 287 char *host; 288 uid_t uid; 289 const char *errstr; 290 291 if (geteuid() != 0) { 292 fprintf(stderr, "mrinfo: must be root\n"); 293 exit(1); 294 } 295 296 init_igmp(); 297 298 uid = getuid(); 299 if (setresuid(uid, uid, uid) == -1) 300 err(1, "setresuid"); 301 302 setvbuf(stderr, NULL, _IOLBF, 0); 303 304 while ((ch = getopt(argc, argv, "d::nr:t:")) != -1) { 305 switch (ch) { 306 case 'd': 307 if (!optarg) 308 debug = DEFAULT_DEBUG; 309 else { 310 debug = strtonum(optarg, 0, 3, &errstr); 311 if (errstr) { 312 warnx("debug level %s", errstr); 313 debug = DEFAULT_DEBUG; 314 } 315 } 316 break; 317 case 'n': 318 ++nflag; 319 break; 320 case 'r': 321 retries = strtonum(optarg, 0, INT_MAX, &errstr); 322 if (errstr) { 323 warnx("retries %s", errstr); 324 usage(); 325 } 326 break; 327 case 't': 328 timeout = strtonum(optarg, 0, INT_MAX, &errstr); 329 if (errstr) { 330 warnx("timeout %s", errstr); 331 usage(); 332 } 333 break; 334 default: 335 usage(); 336 } 337 } 338 argc -= optind; 339 argv += optind; 340 341 if (argc > 1) 342 usage(); 343 if (argc == 1) 344 host = argv[0]; 345 else 346 host = "127.0.0.1"; 347 348 if ((target_addr = inet_addr(host)) != -1) { 349 hp = &bogus; 350 hp->h_length = sizeof(target_addr); 351 if (!(hp->h_addr_list = calloc(2, sizeof(char *)))) 352 err(1, "can't allocate memory"); 353 if (!(hp->h_addr_list[0] = malloc(hp->h_length))) 354 err(1, "can't allocate memory"); 355 memcpy(hp->h_addr_list[0], &target_addr, hp->h_length); 356 hp->h_addr_list[1] = 0; 357 } else 358 hp = gethostbyname(host); 359 360 if (hp == NULL || hp->h_length != sizeof(target_addr)) { 361 fprintf(stderr, "mrinfo: %s: no such host\n", argv[0]); 362 exit(1); 363 } 364 if (debug) 365 fprintf(stderr, "Debug level %u\n", debug); 366 367 /* Check all addresses; mrouters often have unreachable interfaces */ 368 for (curaddr = 0; hp->h_addr_list[curaddr] != NULL; curaddr++) { 369 memcpy(&target_addr, hp->h_addr_list[curaddr], hp->h_length); 370 /* Find a good local address for us. */ 371 addrlen = sizeof(addr); 372 memset(&addr, 0, sizeof addr); 373 addr.sin_family = AF_INET; 374 addr.sin_len = sizeof addr; 375 addr.sin_addr.s_addr = target_addr; 376 addr.sin_port = htons(2000); /* any port over 1024 will 377 * do... */ 378 if ((udp = socket(AF_INET, SOCK_DGRAM, 0)) < 0 || 379 connect(udp, (struct sockaddr *) & addr, sizeof(addr)) < 0 || 380 getsockname(udp, (struct sockaddr *) & addr, &addrlen) < 0) { 381 perror("Determining local address"); 382 exit(1); 383 } 384 close(udp); 385 our_addr = addr.sin_addr.s_addr; 386 387 tries = 0; 388 trynew = 1; 389 /* 390 * New strategy: send 'ask2' for two timeouts, then fall back 391 * to 'ask', since it's not very likely that we are going to 392 * find someone who only responds to 'ask' these days 393 */ 394 ask2(target_addr); 395 396 gettimeofday(&et, 0); 397 et.tv_sec += timeout; 398 399 /* Main receive loop */ 400 for (;;) { 401 int count, recvlen, ipdatalen, iphdrlen, igmpdatalen; 402 u_int32_t src, dst, group; 403 struct timeval tv, now; 404 socklen_t dummy = 0; 405 struct igmp *igmp; 406 struct ip *ip; 407 struct pollfd pfd[1]; 408 409 pfd[0].fd = igmp_socket; 410 pfd[0].events = POLLIN; 411 412 gettimeofday(&now, 0); 413 tv.tv_sec = et.tv_sec - now.tv_sec; 414 tv.tv_usec = et.tv_usec - now.tv_usec; 415 416 if (tv.tv_usec < 0) { 417 tv.tv_usec += 1000000L; 418 --tv.tv_sec; 419 } 420 if (tv.tv_sec < 0) 421 timerclear(&tv); 422 423 count = poll(pfd, 1, tv.tv_sec * 1000); 424 425 if (count < 0) { 426 if (errno != EINTR) 427 perror("select"); 428 continue; 429 } else if (count == 0) { 430 logit(LOG_DEBUG, 0, 431 "Timed out receiving neighbor lists"); 432 if (++tries > retries) 433 break; 434 /* If we've tried ASK_NEIGHBORS2 twice with 435 * no response, fall back to ASK_NEIGHBORS 436 */ 437 if (tries == 2 && target_level == 0) 438 trynew = 0; 439 if (target_level == 0 && trynew == 0) 440 ask(target_addr); 441 else 442 ask2(target_addr); 443 gettimeofday(&et, 0); 444 et.tv_sec += timeout; 445 continue; 446 } 447 recvlen = recvfrom(igmp_socket, recv_buf, RECV_BUF_SIZE, 448 0, NULL, &dummy); 449 if (recvlen <= 0) { 450 if (recvlen && errno != EINTR) 451 perror("recvfrom"); 452 continue; 453 } 454 455 if (recvlen < sizeof(struct ip)) { 456 logit(LOG_WARNING, 0, 457 "packet too short (%u bytes) for IP header", 458 recvlen); 459 continue; 460 } 461 ip = (struct ip *) recv_buf; 462 if (ip->ip_p == 0) 463 continue; /* Request to install cache entry */ 464 src = ip->ip_src.s_addr; 465 dst = ip->ip_dst.s_addr; 466 iphdrlen = ip->ip_hl << 2; 467 ipdatalen = ntohs(ip->ip_len) - iphdrlen; 468 if (iphdrlen + ipdatalen != recvlen) { 469 logit(LOG_WARNING, 0, 470 "packet shorter (%u bytes) than " 471 "hdr+data length (%u+%u)", 472 recvlen, iphdrlen, ipdatalen); 473 continue; 474 } 475 igmp = (struct igmp *) (recv_buf + iphdrlen); 476 group = igmp->igmp_group.s_addr; 477 igmpdatalen = ipdatalen - IGMP_MINLEN; 478 if (igmpdatalen < 0) { 479 logit(LOG_WARNING, 0, 480 "IP data field too short (%u bytes) " 481 "for IGMP, from %s", 482 ipdatalen, inet_fmt(src, s1)); 483 continue; 484 } 485 if (igmp->igmp_type != IGMP_DVMRP) 486 continue; 487 488 switch (igmp->igmp_code) { 489 case DVMRP_NEIGHBORS: 490 case DVMRP_NEIGHBORS2: 491 if (src != target_addr) { 492 fprintf(stderr, "mrinfo: got reply from %s", 493 inet_fmt(src, s1)); 494 fprintf(stderr, " instead of %s\n", 495 inet_fmt(target_addr, s1)); 496 /*continue;*/ 497 } 498 break; 499 default: 500 continue; /* ignore all other DVMRP messages */ 501 } 502 503 switch (igmp->igmp_code) { 504 case DVMRP_NEIGHBORS: 505 if (group) { 506 /* knows about DVMRP_NEIGHBORS2 msg */ 507 if (target_level == 0) { 508 target_level = ntohl(group); 509 ask2(target_addr); 510 } 511 } else { 512 accept_neighbors(src, dst, (u_char *)(igmp + 1), 513 igmpdatalen, ntohl(group)); 514 exit(0); 515 } 516 break; 517 case DVMRP_NEIGHBORS2: 518 accept_neighbors2(src, dst, (u_char *)(igmp + 1), 519 igmpdatalen, ntohl(group)); 520 exit(0); 521 } 522 } 523 } 524 exit(1); 525 } 526 527 /* dummies */ 528 void 529 accept_probe(u_int32_t src, u_int32_t dst, char *p, int datalen, 530 u_int32_t level) 531 { 532 } 533 534 void 535 accept_group_report(u_int32_t src, u_int32_t dst, u_int32_t group, int r_type) 536 { 537 } 538 539 void 540 accept_neighbor_request2(u_int32_t src, u_int32_t dst) 541 { 542 } 543 544 void 545 accept_report(u_int32_t src, u_int32_t dst, char *p, int datalen, 546 u_int32_t level) 547 { 548 } 549 550 void 551 accept_neighbor_request(u_int32_t src, u_int32_t dst) 552 { 553 } 554 555 void 556 accept_prune(u_int32_t src, u_int32_t dst, char *p, int datalen) 557 { 558 } 559 560 void 561 accept_graft(u_int32_t src, u_int32_t dst, char *p, int datalen) 562 { 563 } 564 565 void 566 accept_g_ack(u_int32_t src, u_int32_t dst, char *p, int datalen) 567 { 568 } 569 570 void 571 add_table_entry(u_int32_t origin, u_int32_t mcastgrp) 572 { 573 } 574 575 void 576 check_vif_state(void) 577 { 578 } 579 580 void 581 accept_leave_message(u_int32_t src, u_int32_t dst, u_int32_t group) 582 { 583 } 584 585 void 586 accept_mtrace(u_int32_t src, u_int32_t dst, u_int32_t group, char *data, 587 u_int no, int datalen) 588 { 589 } 590 591 void 592 accept_membership_query(u_int32_t src, u_int32_t dst, u_int32_t group, int tmo) 593 { 594 } 595 596 void 597 accept_info_request(u_int32_t src, u_int32_t dst, u_char *p, int datalen) 598 { 599 } 600 601 void 602 accept_info_reply(u_int32_t src, u_int32_t dst, u_char *p, int datalen) 603 { 604 } 605