mrinfo.c revision 1.2
1 /* 2 * This tool requests configuration info from a multicast router 3 * and prints the reply (if any). Invoke it as: 4 * 5 * mrinfo router-name-or-address 6 * 7 * Written Wed Mar 24 1993 by Van Jacobson (adapted from the 8 * multicast mapper written by Pavel Curtis). 9 * 10 * The lawyers insist we include the following UC copyright notice. 11 * The mapper from which this is derived contained a Xerox copyright 12 * notice which follows the UC one. Try not to get depressed noting 13 * that the legal gibberish is larger than the program. 14 * 15 * Copyright (c) 1993 Regents of the University of California. 16 * All rights reserved. 17 * 18 * Redistribution and use in source and binary forms, with or without 19 * modification, are permitted provided that the following conditions 20 * are met: 21 * 1. Redistributions of source code must retain the above copyright 22 * notice, this list of conditions and the following disclaimer. 23 * 2. Redistributions in binary form must reproduce the above copyright 24 * notice, this list of conditions and the following disclaimer in the 25 * documentation and/or other materials provided with the distribution. 26 * 3. All advertising materials mentioning features or use of this software 27 * must display the following acknowledgement: 28 * This product includes software developed by the Computer Systems 29 * Engineering Group at Lawrence Berkeley Laboratory. 30 * 4. Neither the name of the University nor of the Laboratory may be used 31 * to endorse or promote products derived from this software without 32 * specific prior written permission. 33 * 34 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 35 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 36 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 37 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 38 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 39 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 40 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 41 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 42 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 43 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 44 * SUCH DAMAGE. 45 * --------------------------------- 46 * Copyright (c) Xerox Corporation 1992. All rights reserved. 47 * 48 * License is granted to copy, to use, and to make and to use derivative works 49 * for research and evaluation purposes, provided that Xerox is acknowledged 50 * in all documentation pertaining to any such copy or derivative work. Xerox 51 * grants no other licenses expressed or implied. The Xerox trade name should 52 * not be used in any advertising without its written permission. 53 * 54 * XEROX CORPORATION MAKES NO REPRESENTATIONS CONCERNING EITHER THE 55 * MERCHANTABILITY OF THIS SOFTWARE OR THE SUITABILITY OF THIS SOFTWARE FOR 56 * ANY PARTICULAR PURPOSE. The software is provided "as is" without express 57 * or implied warranty of any kind. 58 * 59 * These notices must be retained in any copies of any part of this software. 60 */ 61 62 #ifndef lint 63 static char rcsid[] = 64 "@(#) $Id: mrinfo.c,v 1.2 1995/06/07 17:38:35 cgd Exp $"; 65 /* original rcsid: 66 "@(#) Header: mrinfo.c,v 1.6 93/04/08 15:14:16 van Exp (LBL)"; 67 */ 68 #endif 69 70 #include <string.h> 71 #include <netdb.h> 72 #include <sys/time.h> 73 #include "defs.h" 74 #include <arpa/inet.h> 75 76 #define DEFAULT_TIMEOUT 4 /* How long to wait before retrying requests */ 77 #define DEFAULT_RETRIES 3 /* How many times to ask each router */ 78 79 u_int32_t our_addr, target_addr = 0; /* in NET order */ 80 int debug = 0; 81 int nflag = 0; 82 int retries = DEFAULT_RETRIES; 83 int timeout = DEFAULT_TIMEOUT; 84 int target_level; 85 vifi_t numvifs; /* to keep loader happy */ 86 /* (see COPY_TABLES macro called in kern.c) */ 87 88 char * 89 inet_name(addr) 90 u_int32_t addr; 91 { 92 struct hostent *e; 93 struct in_addr in; 94 95 if (addr == 0) 96 return "local"; 97 98 if (nflag || 99 (e = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET)) == NULL) { 100 in.s_addr = addr; 101 return (inet_ntoa(in)); 102 } 103 return (e->h_name); 104 } 105 106 /* 107 * Log errors and other messages to stderr, according to the severity of the 108 * message and the current debug level. For errors of severity LOG_ERR or 109 * worse, terminate the program. 110 */ 111 void 112 log(severity, syserr, format, a, b, c, d, e) 113 int severity, syserr; 114 char *format; 115 int a, b, c, d, e; 116 { 117 char fmt[100]; 118 119 switch (debug) { 120 case 0: 121 if (severity > LOG_WARNING) 122 return; 123 case 1: 124 if (severity > LOG_NOTICE) 125 return; 126 case 2: 127 if (severity > LOG_INFO) 128 return; 129 default: 130 fmt[0] = '\0'; 131 if (severity == LOG_WARNING) 132 strcat(fmt, "warning - "); 133 strncat(fmt, format, 80); 134 fprintf(stderr, fmt, a, b, c, d, e); 135 if (syserr == 0) 136 fprintf(stderr, "\n"); 137 else if (syserr < sys_nerr) 138 fprintf(stderr, ": %s\n", sys_errlist[syserr]); 139 else 140 fprintf(stderr, ": errno %d\n", syserr); 141 } 142 143 if (severity <= LOG_ERR) 144 exit(-1); 145 } 146 147 /* 148 * Send a neighbors-list request. 149 */ 150 void 151 ask(dst) 152 u_int32_t dst; 153 { 154 send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS, 155 htonl(MROUTED_LEVEL), 0); 156 } 157 158 void 159 ask2(dst) 160 u_int32_t dst; 161 { 162 send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS2, 163 htonl(MROUTED_LEVEL), 0); 164 } 165 166 /* 167 * Process an incoming neighbor-list message. 168 */ 169 void 170 accept_neighbors(src, dst, p, datalen) 171 u_int32_t src, dst; 172 u_char *p; 173 int datalen; 174 { 175 u_char *ep = p + datalen; 176 #define GET_ADDR(a) (a = ((u_int32_t)*p++ << 24), a += ((u_int32_t)*p++ << 16),\ 177 a += ((u_int32_t)*p++ << 8), a += *p++) 178 179 printf("%s (%s):\n", inet_fmt(src, s1), inet_name(src)); 180 while (p < ep) { 181 register u_int32_t laddr; 182 register u_char metric; 183 register u_char thresh; 184 register int ncount; 185 186 GET_ADDR(laddr); 187 laddr = htonl(laddr); 188 metric = *p++; 189 thresh = *p++; 190 ncount = *p++; 191 while (--ncount >= 0) { 192 register u_int32_t neighbor; 193 GET_ADDR(neighbor); 194 neighbor = htonl(neighbor); 195 printf(" %s -> ", inet_fmt(laddr, s1)); 196 printf("%s (%s) [%d/%d]\n", inet_fmt(neighbor, s1), 197 inet_name(neighbor), metric, thresh); 198 } 199 } 200 } 201 202 void 203 accept_neighbors2(src, dst, p, datalen) 204 u_int32_t src, dst; 205 u_char *p; 206 int datalen; 207 { 208 u_char *ep = p + datalen; 209 u_int broken_cisco = ((target_level & 0xffff) == 0x020a); /* 10.2 */ 210 /* well, only possibly_broken_cisco, but that's too long to type. */ 211 212 printf("%s (%s) [version %d.%d]:\n", inet_fmt(src, s1), inet_name(src), 213 target_level & 0xff, (target_level >> 8) & 0xff); 214 215 while (p < ep) { 216 register u_char metric; 217 register u_char thresh; 218 register u_char flags; 219 register int ncount; 220 register u_int32_t laddr = *(u_int32_t*)p; 221 222 p += 4; 223 metric = *p++; 224 thresh = *p++; 225 flags = *p++; 226 ncount = *p++; 227 if (broken_cisco && ncount == 0) /* dumb Ciscos */ 228 ncount = 1; 229 if (broken_cisco && ncount > 15) /* dumb Ciscos */ 230 ncount = ncount & 0xf; 231 while (--ncount >= 0 && p < ep) { 232 register u_int32_t neighbor = *(u_int32_t*)p; 233 p += 4; 234 printf(" %s -> ", inet_fmt(laddr, s1)); 235 printf("%s (%s) [%d/%d", inet_fmt(neighbor, s1), 236 inet_name(neighbor), metric, thresh); 237 if (flags & DVMRP_NF_TUNNEL) 238 printf("/tunnel"); 239 if (flags & DVMRP_NF_SRCRT) 240 printf("/srcrt"); 241 if (flags & DVMRP_NF_PIM) 242 printf("/pim"); 243 if (flags & DVMRP_NF_QUERIER) 244 printf("/querier"); 245 if (flags & DVMRP_NF_DISABLED) 246 printf("/disabled"); 247 if (flags & DVMRP_NF_DOWN) 248 printf("/down"); 249 if (flags & DVMRP_NF_LEAF) 250 printf("/leaf"); 251 printf("]\n"); 252 } 253 } 254 } 255 256 int 257 get_number(var, deflt, pargv, pargc) 258 int *var, *pargc, deflt; 259 char ***pargv; 260 { 261 if ((*pargv)[0][2] == '\0') { /* Get the value from the next 262 * argument */ 263 if (*pargc > 1 && isdigit((*pargv)[1][0])) { 264 (*pargv)++, (*pargc)--; 265 *var = atoi((*pargv)[0]); 266 return 1; 267 } else if (deflt >= 0) { 268 *var = deflt; 269 return 1; 270 } else 271 return 0; 272 } else { /* Get value from the rest of this argument */ 273 if (isdigit((*pargv)[0][2])) { 274 *var = atoi((*pargv)[0] + 2); 275 return 1; 276 } else { 277 return 0; 278 } 279 } 280 } 281 282 u_int32_t 283 host_addr(name) 284 char *name; 285 { 286 struct hostent *e; 287 u_int32_t addr; 288 289 addr = inet_addr(name); 290 if ((int)addr == -1) { 291 e = gethostbyname(name); 292 if (e == NULL || e->h_length != sizeof(addr)) 293 return (0); 294 memcpy(&addr, e->h_addr_list[0], e->h_length); 295 } 296 return(addr); 297 } 298 299 void 300 usage() 301 { 302 fprintf(stderr, 303 "Usage: mrinfo [-n] [-t timeout] [-r retries] [router]\n"); 304 exit(1); 305 } 306 307 int 308 main(argc, argv) 309 int argc; 310 char *argv[]; 311 { 312 setlinebuf(stderr); 313 314 if (geteuid() != 0) { 315 fprintf(stderr, "mrinfo: must be root\n"); 316 exit(1); 317 } 318 argv++, argc--; 319 while (argc > 0 && argv[0][0] == '-') { 320 switch (argv[0][1]) { 321 case 'd': 322 if (!get_number(&debug, DEFAULT_DEBUG, &argv, &argc)) 323 usage(); 324 break; 325 case 'n': 326 ++nflag; 327 break; 328 case 'r': 329 if (!get_number(&retries, -1, &argv, &argc)) 330 usage(); 331 break; 332 case 't': 333 if (!get_number(&timeout, -1, &argv, &argc)) 334 usage(); 335 break; 336 default: 337 usage(); 338 } 339 argv++, argc--; 340 } 341 if (argc > 1) 342 usage(); 343 if (argc == 1) 344 target_addr = host_addr(argv[0]); 345 else 346 target_addr = host_addr("127.0.0.1"); 347 348 if (target_addr == 0) { 349 fprintf(stderr, "mrinfo: %s: no such host\n", argv[0]); 350 exit(1); 351 } 352 if (debug) 353 fprintf(stderr, "Debug level %u\n", debug); 354 355 init_igmp(); 356 357 { /* Find a good local address for us. */ 358 int udp; 359 struct sockaddr_in addr; 360 int addrlen = sizeof(addr); 361 362 addr.sin_family = AF_INET; 363 #if (defined(BSD) && (BSD >= 199103)) 364 addr.sin_len = sizeof addr; 365 #endif 366 addr.sin_addr.s_addr = target_addr; 367 addr.sin_port = htons(2000); /* any port over 1024 will 368 * do... */ 369 if ((udp = socket(AF_INET, SOCK_DGRAM, 0)) < 0 370 || connect(udp, (struct sockaddr *) & addr, sizeof(addr)) < 0 371 || getsockname(udp, (struct sockaddr *) & addr, &addrlen) < 0) { 372 perror("Determining local address"); 373 exit(-1); 374 } 375 close(udp); 376 our_addr = addr.sin_addr.s_addr; 377 } 378 379 ask(target_addr); 380 381 /* Main receive loop */ 382 for (;;) { 383 fd_set fds; 384 struct timeval tv; 385 int count, recvlen, dummy = 0; 386 register u_int32_t src, dst, group; 387 struct ip *ip; 388 struct igmp *igmp; 389 int ipdatalen, iphdrlen, igmpdatalen; 390 391 FD_ZERO(&fds); 392 FD_SET(igmp_socket, &fds); 393 394 tv.tv_sec = timeout; 395 tv.tv_usec = 0; 396 397 count = select(igmp_socket + 1, &fds, 0, 0, &tv); 398 399 if (count < 0) { 400 if (errno != EINTR) 401 perror("select"); 402 continue; 403 } else if (count == 0) { 404 log(LOG_DEBUG, 0, "Timed out receiving neighbor lists"); 405 if (--retries < 0) 406 exit(1); 407 if (target_level == 0) 408 ask(target_addr); 409 else 410 ask2(target_addr); 411 continue; 412 } 413 recvlen = recvfrom(igmp_socket, recv_buf, RECV_BUF_SIZE, 414 0, NULL, &dummy); 415 if (recvlen <= 0) { 416 if (recvlen && errno != EINTR) 417 perror("recvfrom"); 418 continue; 419 } 420 421 if (recvlen < sizeof(struct ip)) { 422 log(LOG_WARNING, 0, 423 "packet too short (%u bytes) for IP header", 424 recvlen); 425 continue; 426 } 427 ip = (struct ip *) recv_buf; 428 if (ip->ip_p == 0) 429 continue; /* Request to install cache entry */ 430 src = ip->ip_src.s_addr; 431 dst = ip->ip_dst.s_addr; 432 iphdrlen = ip->ip_hl << 2; 433 ipdatalen = ip->ip_len; 434 if (iphdrlen + ipdatalen != recvlen) { 435 log(LOG_WARNING, 0, 436 "packet shorter (%u bytes) than hdr+data length (%u+%u)", 437 recvlen, iphdrlen, ipdatalen); 438 continue; 439 } 440 igmp = (struct igmp *) (recv_buf + iphdrlen); 441 group = igmp->igmp_group.s_addr; 442 igmpdatalen = ipdatalen - IGMP_MINLEN; 443 if (igmpdatalen < 0) { 444 log(LOG_WARNING, 0, 445 "IP data field too short (%u bytes) for IGMP, from %s", 446 ipdatalen, inet_fmt(src, s1)); 447 continue; 448 } 449 if (igmp->igmp_type != IGMP_DVMRP) 450 continue; 451 452 switch (igmp->igmp_code) { 453 case DVMRP_NEIGHBORS: 454 case DVMRP_NEIGHBORS2: 455 if (src != target_addr) { 456 fprintf(stderr, "mrinfo: got reply from %s", 457 inet_fmt(src, s1)); 458 fprintf(stderr, " instead of %s\n", 459 inet_fmt(target_addr, s1)); 460 /*continue;*/ 461 } 462 break; 463 default: 464 continue; /* ignore all other DVMRP messages */ 465 } 466 467 switch (igmp->igmp_code) { 468 469 case DVMRP_NEIGHBORS: 470 if (group) { 471 /* knows about DVMRP_NEIGHBORS2 msg */ 472 if (target_level == 0) { 473 target_level = ntohl(group); 474 ask2(target_addr); 475 } 476 } else { 477 accept_neighbors(src, dst, (char *)(igmp + 1), 478 igmpdatalen); 479 exit(0); 480 } 481 break; 482 483 case DVMRP_NEIGHBORS2: 484 accept_neighbors2(src, dst, (char *)(igmp + 1), 485 igmpdatalen); 486 exit(0); 487 } 488 } 489 } 490 491 /* dummies */ 492 void accept_probe() 493 { 494 } 495 void accept_group_report() 496 { 497 } 498 void accept_neighbor_request2() 499 { 500 } 501 void accept_report() 502 { 503 } 504 void accept_neighbor_request() 505 { 506 } 507 void accept_prune() 508 { 509 } 510 void accept_graft() 511 { 512 } 513 void accept_g_ack() 514 { 515 } 516 void add_table_entry() 517 { 518 } 519 void check_vif_state() 520 { 521 } 522 void accept_leave_message() 523 { 524 } 525 void accept_mtrace() 526 { 527 } 528 void accept_membership_query() 529 { 530 } 531
Indexes created Tue Oct 14 01:09:49 GMT 2025