print-icmp.c revision 1.6
1 /* 2 * Copyright (c) 1988, 1989, 1990, 1991, 1993, 1994, 1995, 1996 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that: (1) source code distributions 7 * retain the above copyright notice and this paragraph in its entirety, (2) 8 * distributions including binary code include the above copyright notice and 9 * this paragraph in its entirety in the documentation or other materials 10 * provided with the distribution, and (3) all advertising materials mentioning 11 * features or use of this software display the following acknowledgement: 12 * ``This product includes software developed by the University of California, 13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of 14 * the University nor the names of its contributors may be used to endorse 15 * or promote products derived from this software without specific prior 16 * written permission. 17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED 18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF 19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 20 */ 21 22 #include <sys/cdefs.h> 23 #ifndef lint 24 __RCSID("$NetBSD: print-icmp.c,v 1.6 2015/03/31 21:59:35 christos Exp $"); 25 #endif 26 27 #define NETDISSECT_REWORKED 28 #ifdef HAVE_CONFIG_H 29 #include "config.h" 30 #endif 31 32 #include <tcpdump-stdinc.h> 33 34 #include <stdio.h> 35 #include <string.h> 36 37 #include "interface.h" 38 #include "addrtoname.h" 39 #include "extract.h" /* must come after interface.h */ 40 41 #include "ip.h" 42 #include "udp.h" 43 #include "ipproto.h" 44 #include "mpls.h" 45 46 /* 47 * Interface Control Message Protocol Definitions. 48 * Per RFC 792, September 1981. 49 */ 50 51 /* 52 * Structure of an icmp header. 53 */ 54 struct icmp { 55 uint8_t icmp_type; /* type of message, see below */ 56 uint8_t icmp_code; /* type sub code */ 57 uint16_t icmp_cksum; /* ones complement cksum of struct */ 58 union { 59 uint8_t ih_pptr; /* ICMP_PARAMPROB */ 60 struct in_addr ih_gwaddr; /* ICMP_REDIRECT */ 61 struct ih_idseq { 62 uint16_t icd_id; 63 uint16_t icd_seq; 64 } ih_idseq; 65 uint32_t ih_void; 66 } icmp_hun; 67 #define icmp_pptr icmp_hun.ih_pptr 68 #define icmp_gwaddr icmp_hun.ih_gwaddr 69 #define icmp_id icmp_hun.ih_idseq.icd_id 70 #define icmp_seq icmp_hun.ih_idseq.icd_seq 71 #define icmp_void icmp_hun.ih_void 72 union { 73 struct id_ts { 74 uint32_t its_otime; 75 uint32_t its_rtime; 76 uint32_t its_ttime; 77 } id_ts; 78 struct id_ip { 79 struct ip idi_ip; 80 /* options and then 64 bits of data */ 81 } id_ip; 82 uint32_t id_mask; 83 uint8_t id_data[1]; 84 } icmp_dun; 85 #define icmp_otime icmp_dun.id_ts.its_otime 86 #define icmp_rtime icmp_dun.id_ts.its_rtime 87 #define icmp_ttime icmp_dun.id_ts.its_ttime 88 #define icmp_ip icmp_dun.id_ip.idi_ip 89 #define icmp_mask icmp_dun.id_mask 90 #define icmp_data icmp_dun.id_data 91 }; 92 93 #define ICMP_MPLS_EXT_EXTRACT_VERSION(x) (((x)&0xf0)>>4) 94 #define ICMP_MPLS_EXT_VERSION 2 95 96 /* 97 * Lower bounds on packet lengths for various types. 98 * For the error advice packets must first insure that the 99 * packet is large enought to contain the returned ip header. 100 * Only then can we do the check to see if 64 bits of packet 101 * data have been returned, since we need to check the returned 102 * ip header length. 103 */ 104 #define ICMP_MINLEN 8 /* abs minimum */ 105 #define ICMP_EXTD_MINLEN (156 - sizeof (struct ip)) /* draft-bonica-internet-icmp-08 */ 106 #define ICMP_TSLEN (8 + 3 * sizeof (uint32_t)) /* timestamp */ 107 #define ICMP_MASKLEN 12 /* address mask */ 108 #define ICMP_ADVLENMIN (8 + sizeof (struct ip) + 8) /* min */ 109 #define ICMP_ADVLEN(p) (8 + (IP_HL(&(p)->icmp_ip) << 2) + 8) 110 /* N.B.: must separately check that ip_hl >= 5 */ 111 112 /* 113 * Definition of type and code field values. 114 */ 115 #define ICMP_ECHOREPLY 0 /* echo reply */ 116 #define ICMP_UNREACH 3 /* dest unreachable, codes: */ 117 #define ICMP_UNREACH_NET 0 /* bad net */ 118 #define ICMP_UNREACH_HOST 1 /* bad host */ 119 #define ICMP_UNREACH_PROTOCOL 2 /* bad protocol */ 120 #define ICMP_UNREACH_PORT 3 /* bad port */ 121 #define ICMP_UNREACH_NEEDFRAG 4 /* IP_DF caused drop */ 122 #define ICMP_UNREACH_SRCFAIL 5 /* src route failed */ 123 #define ICMP_UNREACH_NET_UNKNOWN 6 /* unknown net */ 124 #define ICMP_UNREACH_HOST_UNKNOWN 7 /* unknown host */ 125 #define ICMP_UNREACH_ISOLATED 8 /* src host isolated */ 126 #define ICMP_UNREACH_NET_PROHIB 9 /* prohibited access */ 127 #define ICMP_UNREACH_HOST_PROHIB 10 /* ditto */ 128 #define ICMP_UNREACH_TOSNET 11 /* bad tos for net */ 129 #define ICMP_UNREACH_TOSHOST 12 /* bad tos for host */ 130 #define ICMP_SOURCEQUENCH 4 /* packet lost, slow down */ 131 #define ICMP_REDIRECT 5 /* shorter route, codes: */ 132 #define ICMP_REDIRECT_NET 0 /* for network */ 133 #define ICMP_REDIRECT_HOST 1 /* for host */ 134 #define ICMP_REDIRECT_TOSNET 2 /* for tos and net */ 135 #define ICMP_REDIRECT_TOSHOST 3 /* for tos and host */ 136 #define ICMP_ECHO 8 /* echo service */ 137 #define ICMP_ROUTERADVERT 9 /* router advertisement */ 138 #define ICMP_ROUTERSOLICIT 10 /* router solicitation */ 139 #define ICMP_TIMXCEED 11 /* time exceeded, code: */ 140 #define ICMP_TIMXCEED_INTRANS 0 /* ttl==0 in transit */ 141 #define ICMP_TIMXCEED_REASS 1 /* ttl==0 in reass */ 142 #define ICMP_PARAMPROB 12 /* ip header bad */ 143 #define ICMP_PARAMPROB_OPTABSENT 1 /* req. opt. absent */ 144 #define ICMP_TSTAMP 13 /* timestamp request */ 145 #define ICMP_TSTAMPREPLY 14 /* timestamp reply */ 146 #define ICMP_IREQ 15 /* information request */ 147 #define ICMP_IREQREPLY 16 /* information reply */ 148 #define ICMP_MASKREQ 17 /* address mask request */ 149 #define ICMP_MASKREPLY 18 /* address mask reply */ 150 151 #define ICMP_MAXTYPE 18 152 153 #define ICMP_ERRTYPE(type) \ 154 ((type) == ICMP_UNREACH || (type) == ICMP_SOURCEQUENCH || \ 155 (type) == ICMP_REDIRECT || (type) == ICMP_TIMXCEED || \ 156 (type) == ICMP_PARAMPROB) 157 #define ICMP_MPLS_EXT_TYPE(type) \ 158 ((type) == ICMP_UNREACH || \ 159 (type) == ICMP_TIMXCEED || \ 160 (type) == ICMP_PARAMPROB) 161 /* rfc1700 */ 162 #ifndef ICMP_UNREACH_NET_UNKNOWN 163 #define ICMP_UNREACH_NET_UNKNOWN 6 /* destination net unknown */ 164 #endif 165 #ifndef ICMP_UNREACH_HOST_UNKNOWN 166 #define ICMP_UNREACH_HOST_UNKNOWN 7 /* destination host unknown */ 167 #endif 168 #ifndef ICMP_UNREACH_ISOLATED 169 #define ICMP_UNREACH_ISOLATED 8 /* source host isolated */ 170 #endif 171 #ifndef ICMP_UNREACH_NET_PROHIB 172 #define ICMP_UNREACH_NET_PROHIB 9 /* admin prohibited net */ 173 #endif 174 #ifndef ICMP_UNREACH_HOST_PROHIB 175 #define ICMP_UNREACH_HOST_PROHIB 10 /* admin prohibited host */ 176 #endif 177 #ifndef ICMP_UNREACH_TOSNET 178 #define ICMP_UNREACH_TOSNET 11 /* tos prohibited net */ 179 #endif 180 #ifndef ICMP_UNREACH_TOSHOST 181 #define ICMP_UNREACH_TOSHOST 12 /* tos prohibited host */ 182 #endif 183 184 /* rfc1716 */ 185 #ifndef ICMP_UNREACH_FILTER_PROHIB 186 #define ICMP_UNREACH_FILTER_PROHIB 13 /* admin prohibited filter */ 187 #endif 188 #ifndef ICMP_UNREACH_HOST_PRECEDENCE 189 #define ICMP_UNREACH_HOST_PRECEDENCE 14 /* host precedence violation */ 190 #endif 191 #ifndef ICMP_UNREACH_PRECEDENCE_CUTOFF 192 #define ICMP_UNREACH_PRECEDENCE_CUTOFF 15 /* precedence cutoff */ 193 #endif 194 195 /* Most of the icmp types */ 196 static const struct tok icmp2str[] = { 197 { ICMP_ECHOREPLY, "echo reply" }, 198 { ICMP_SOURCEQUENCH, "source quench" }, 199 { ICMP_ECHO, "echo request" }, 200 { ICMP_ROUTERSOLICIT, "router solicitation" }, 201 { ICMP_TSTAMP, "time stamp request" }, 202 { ICMP_TSTAMPREPLY, "time stamp reply" }, 203 { ICMP_IREQ, "information request" }, 204 { ICMP_IREQREPLY, "information reply" }, 205 { ICMP_MASKREQ, "address mask request" }, 206 { 0, NULL } 207 }; 208 209 /* Formats for most of the ICMP_UNREACH codes */ 210 static const struct tok unreach2str[] = { 211 { ICMP_UNREACH_NET, "net %s unreachable" }, 212 { ICMP_UNREACH_HOST, "host %s unreachable" }, 213 { ICMP_UNREACH_SRCFAIL, 214 "%s unreachable - source route failed" }, 215 { ICMP_UNREACH_NET_UNKNOWN, "net %s unreachable - unknown" }, 216 { ICMP_UNREACH_HOST_UNKNOWN, "host %s unreachable - unknown" }, 217 { ICMP_UNREACH_ISOLATED, 218 "%s unreachable - source host isolated" }, 219 { ICMP_UNREACH_NET_PROHIB, 220 "net %s unreachable - admin prohibited" }, 221 { ICMP_UNREACH_HOST_PROHIB, 222 "host %s unreachable - admin prohibited" }, 223 { ICMP_UNREACH_TOSNET, 224 "net %s unreachable - tos prohibited" }, 225 { ICMP_UNREACH_TOSHOST, 226 "host %s unreachable - tos prohibited" }, 227 { ICMP_UNREACH_FILTER_PROHIB, 228 "host %s unreachable - admin prohibited filter" }, 229 { ICMP_UNREACH_HOST_PRECEDENCE, 230 "host %s unreachable - host precedence violation" }, 231 { ICMP_UNREACH_PRECEDENCE_CUTOFF, 232 "host %s unreachable - precedence cutoff" }, 233 { 0, NULL } 234 }; 235 236 /* Formats for the ICMP_REDIRECT codes */ 237 static const struct tok type2str[] = { 238 { ICMP_REDIRECT_NET, "redirect %s to net %s" }, 239 { ICMP_REDIRECT_HOST, "redirect %s to host %s" }, 240 { ICMP_REDIRECT_TOSNET, "redirect-tos %s to net %s" }, 241 { ICMP_REDIRECT_TOSHOST, "redirect-tos %s to host %s" }, 242 { 0, NULL } 243 }; 244 245 /* rfc1191 */ 246 struct mtu_discovery { 247 uint16_t unused; 248 uint16_t nexthopmtu; 249 }; 250 251 /* rfc1256 */ 252 struct ih_rdiscovery { 253 uint8_t ird_addrnum; 254 uint8_t ird_addrsiz; 255 uint16_t ird_lifetime; 256 }; 257 258 struct id_rdiscovery { 259 uint32_t ird_addr; 260 uint32_t ird_pref; 261 }; 262 263 /* 264 * draft-bonica-internet-icmp-08 265 * 266 * The Destination Unreachable, Time Exceeded 267 * and Parameter Problem messages are slighly changed as per 268 * the above draft. A new Length field gets added to give 269 * the caller an idea about the length of the piggypacked 270 * IP packet before the MPLS extension header starts. 271 * 272 * The Length field represents length of the padded "original datagram" 273 * field measured in 32-bit words. 274 * 275 * 0 1 2 3 276 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 277 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 278 * | Type | Code | Checksum | 279 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 280 * | unused | Length | unused | 281 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 282 * | Internet Header + leading octets of original datagram | 283 * | | 284 * | // | 285 * | | 286 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 287 */ 288 289 struct icmp_ext_t { 290 uint8_t icmp_type; 291 uint8_t icmp_code; 292 uint8_t icmp_checksum[2]; 293 uint8_t icmp_reserved; 294 uint8_t icmp_length; 295 uint8_t icmp_reserved2[2]; 296 uint8_t icmp_ext_legacy_header[128]; /* extension header starts 128 bytes after ICMP header */ 297 uint8_t icmp_ext_version_res[2]; 298 uint8_t icmp_ext_checksum[2]; 299 uint8_t icmp_ext_data[1]; 300 }; 301 302 struct icmp_mpls_ext_object_header_t { 303 uint8_t length[2]; 304 uint8_t class_num; 305 uint8_t ctype; 306 }; 307 308 static const struct tok icmp_mpls_ext_obj_values[] = { 309 { 1, "MPLS Stack Entry" }, 310 { 2, "Extended Payload" }, 311 { 0, NULL} 312 }; 313 314 /* prototypes */ 315 const char *icmp_tstamp_print(u_int); 316 317 /* print the milliseconds since midnight UTC */ 318 const char * 319 icmp_tstamp_print(u_int tstamp) 320 { 321 u_int msec,sec,min,hrs; 322 323 static char buf[64]; 324 325 msec = tstamp % 1000; 326 sec = tstamp / 1000; 327 min = sec / 60; sec -= min * 60; 328 hrs = min / 60; min -= hrs * 60; 329 snprintf(buf, sizeof(buf), "%02u:%02u:%02u.%03u",hrs,min,sec,msec); 330 return buf; 331 } 332 333 void 334 icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *bp2, 335 int fragmented) 336 { 337 char *cp; 338 const struct icmp *dp; 339 const struct icmp_ext_t *ext_dp; 340 const struct ip *ip; 341 const char *str, *fmt; 342 const struct ip *oip; 343 const struct udphdr *ouh; 344 const uint8_t *obj_tptr; 345 uint32_t raw_label; 346 const u_char *snapend_save; 347 const struct icmp_mpls_ext_object_header_t *icmp_mpls_ext_object_header; 348 u_int hlen, dport, mtu, obj_tlen, obj_class_num, obj_ctype; 349 char buf[MAXHOSTNAMELEN + 100]; 350 struct cksum_vec vec[1]; 351 352 dp = (struct icmp *)bp; 353 ext_dp = (struct icmp_ext_t *)bp; 354 ip = (struct ip *)bp2; 355 str = buf; 356 357 ND_TCHECK(dp->icmp_code); 358 switch (dp->icmp_type) { 359 360 case ICMP_ECHO: 361 case ICMP_ECHOREPLY: 362 ND_TCHECK(dp->icmp_seq); 363 (void)snprintf(buf, sizeof(buf), "echo %s, id %u, seq %u", 364 dp->icmp_type == ICMP_ECHO ? 365 "request" : "reply", 366 EXTRACT_16BITS(&dp->icmp_id), 367 EXTRACT_16BITS(&dp->icmp_seq)); 368 break; 369 370 case ICMP_UNREACH: 371 ND_TCHECK(dp->icmp_ip.ip_dst); 372 switch (dp->icmp_code) { 373 374 case ICMP_UNREACH_PROTOCOL: 375 ND_TCHECK(dp->icmp_ip.ip_p); 376 (void)snprintf(buf, sizeof(buf), 377 "%s protocol %d unreachable", 378 ipaddr_string(ndo, &dp->icmp_ip.ip_dst), 379 dp->icmp_ip.ip_p); 380 break; 381 382 case ICMP_UNREACH_PORT: 383 ND_TCHECK(dp->icmp_ip.ip_p); 384 oip = &dp->icmp_ip; 385 hlen = IP_HL(oip) * 4; 386 ouh = (struct udphdr *)(((u_char *)oip) + hlen); 387 ND_TCHECK(ouh->uh_dport); 388 dport = EXTRACT_16BITS(&ouh->uh_dport); 389 switch (oip->ip_p) { 390 391 case IPPROTO_TCP: 392 (void)snprintf(buf, sizeof(buf), 393 "%s tcp port %s unreachable", 394 ipaddr_string(ndo, &oip->ip_dst), 395 tcpport_string(dport)); 396 break; 397 398 case IPPROTO_UDP: 399 (void)snprintf(buf, sizeof(buf), 400 "%s udp port %s unreachable", 401 ipaddr_string(ndo, &oip->ip_dst), 402 udpport_string(dport)); 403 break; 404 405 default: 406 (void)snprintf(buf, sizeof(buf), 407 "%s protocol %d port %d unreachable", 408 ipaddr_string(ndo, &oip->ip_dst), 409 oip->ip_p, dport); 410 break; 411 } 412 break; 413 414 case ICMP_UNREACH_NEEDFRAG: 415 { 416 register const struct mtu_discovery *mp; 417 mp = (struct mtu_discovery *)(u_char *)&dp->icmp_void; 418 mtu = EXTRACT_16BITS(&mp->nexthopmtu); 419 if (mtu) { 420 (void)snprintf(buf, sizeof(buf), 421 "%s unreachable - need to frag (mtu %d)", 422 ipaddr_string(ndo, &dp->icmp_ip.ip_dst), mtu); 423 } else { 424 (void)snprintf(buf, sizeof(buf), 425 "%s unreachable - need to frag", 426 ipaddr_string(ndo, &dp->icmp_ip.ip_dst)); 427 } 428 } 429 break; 430 431 default: 432 fmt = tok2str(unreach2str, "#%d %%s unreachable", 433 dp->icmp_code); 434 (void)snprintf(buf, sizeof(buf), fmt, 435 ipaddr_string(ndo, &dp->icmp_ip.ip_dst)); 436 break; 437 } 438 break; 439 440 case ICMP_REDIRECT: 441 ND_TCHECK(dp->icmp_ip.ip_dst); 442 fmt = tok2str(type2str, "redirect-#%d %%s to net %%s", 443 dp->icmp_code); 444 (void)snprintf(buf, sizeof(buf), fmt, 445 ipaddr_string(ndo, &dp->icmp_ip.ip_dst), 446 ipaddr_string(ndo, &dp->icmp_gwaddr)); 447 break; 448 449 case ICMP_ROUTERADVERT: 450 { 451 register const struct ih_rdiscovery *ihp; 452 register const struct id_rdiscovery *idp; 453 u_int lifetime, num, size; 454 455 (void)snprintf(buf, sizeof(buf), "router advertisement"); 456 cp = buf + strlen(buf); 457 458 ihp = (struct ih_rdiscovery *)&dp->icmp_void; 459 ND_TCHECK(*ihp); 460 (void)strncpy(cp, " lifetime ", sizeof(buf) - (cp - buf)); 461 cp = buf + strlen(buf); 462 lifetime = EXTRACT_16BITS(&ihp->ird_lifetime); 463 if (lifetime < 60) { 464 (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u", 465 lifetime); 466 } else if (lifetime < 60 * 60) { 467 (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u:%02u", 468 lifetime / 60, lifetime % 60); 469 } else { 470 (void)snprintf(cp, sizeof(buf) - (cp - buf), 471 "%u:%02u:%02u", 472 lifetime / 3600, 473 (lifetime % 3600) / 60, 474 lifetime % 60); 475 } 476 cp = buf + strlen(buf); 477 478 num = ihp->ird_addrnum; 479 (void)snprintf(cp, sizeof(buf) - (cp - buf), " %d:", num); 480 cp = buf + strlen(buf); 481 482 size = ihp->ird_addrsiz; 483 if (size != 2) { 484 (void)snprintf(cp, sizeof(buf) - (cp - buf), 485 " [size %d]", size); 486 break; 487 } 488 idp = (struct id_rdiscovery *)&dp->icmp_data; 489 while (num-- > 0) { 490 ND_TCHECK(*idp); 491 (void)snprintf(cp, sizeof(buf) - (cp - buf), " {%s %u}", 492 ipaddr_string(ndo, &idp->ird_addr), 493 EXTRACT_32BITS(&idp->ird_pref)); 494 cp = buf + strlen(buf); 495 ++idp; 496 } 497 } 498 break; 499 500 case ICMP_TIMXCEED: 501 ND_TCHECK(dp->icmp_ip.ip_dst); 502 switch (dp->icmp_code) { 503 504 case ICMP_TIMXCEED_INTRANS: 505 str = "time exceeded in-transit"; 506 break; 507 508 case ICMP_TIMXCEED_REASS: 509 str = "ip reassembly time exceeded"; 510 break; 511 512 default: 513 (void)snprintf(buf, sizeof(buf), "time exceeded-#%d", 514 dp->icmp_code); 515 break; 516 } 517 break; 518 519 case ICMP_PARAMPROB: 520 if (dp->icmp_code) 521 (void)snprintf(buf, sizeof(buf), 522 "parameter problem - code %d", dp->icmp_code); 523 else { 524 ND_TCHECK(dp->icmp_pptr); 525 (void)snprintf(buf, sizeof(buf), 526 "parameter problem - octet %d", dp->icmp_pptr); 527 } 528 break; 529 530 case ICMP_MASKREPLY: 531 ND_TCHECK(dp->icmp_mask); 532 (void)snprintf(buf, sizeof(buf), "address mask is 0x%08x", 533 EXTRACT_32BITS(&dp->icmp_mask)); 534 break; 535 536 case ICMP_TSTAMP: 537 ND_TCHECK(dp->icmp_seq); 538 (void)snprintf(buf, sizeof(buf), 539 "time stamp query id %u seq %u", 540 EXTRACT_16BITS(&dp->icmp_id), 541 EXTRACT_16BITS(&dp->icmp_seq)); 542 break; 543 544 case ICMP_TSTAMPREPLY: 545 ND_TCHECK(dp->icmp_ttime); 546 (void)snprintf(buf, sizeof(buf), 547 "time stamp reply id %u seq %u: org %s", 548 EXTRACT_16BITS(&dp->icmp_id), 549 EXTRACT_16BITS(&dp->icmp_seq), 550 icmp_tstamp_print(EXTRACT_32BITS(&dp->icmp_otime))); 551 552 (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", recv %s", 553 icmp_tstamp_print(EXTRACT_32BITS(&dp->icmp_rtime))); 554 (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", xmit %s", 555 icmp_tstamp_print(EXTRACT_32BITS(&dp->icmp_ttime))); 556 break; 557 558 default: 559 str = tok2str(icmp2str, "type-#%d", dp->icmp_type); 560 break; 561 } 562 ND_PRINT((ndo, "ICMP %s, length %u", str, plen)); 563 if (ndo->ndo_vflag && !fragmented) { /* don't attempt checksumming if this is a frag */ 564 uint16_t sum, icmp_sum; 565 struct cksum_vec vec[1]; 566 if (ND_TTEST2(*bp, plen)) { 567 vec[0].ptr = (const uint8_t *)(void *)dp; 568 vec[0].len = plen; 569 sum = in_cksum(vec, 1); 570 if (sum != 0) { 571 icmp_sum = EXTRACT_16BITS(&dp->icmp_cksum); 572 ND_PRINT((ndo, " (wrong icmp cksum %x (->%x)!)", 573 icmp_sum, 574 in_cksum_shouldbe(icmp_sum, sum))); 575 } 576 } 577 } 578 579 /* 580 * print the remnants of the IP packet. 581 * save the snaplength as this may get overidden in the IP printer. 582 */ 583 if (ndo->ndo_vflag >= 1 && ICMP_ERRTYPE(dp->icmp_type)) { 584 bp += 8; 585 ND_PRINT((ndo, "\n\t")); 586 ip = (struct ip *)bp; 587 ndo->ndo_snaplen = ndo->ndo_snapend - bp; 588 snapend_save = ndo->ndo_snapend; 589 ip_print(ndo, bp, EXTRACT_16BITS(&ip->ip_len)); 590 ndo->ndo_snapend = snapend_save; 591 } 592 593 /* 594 * Attempt to decode the MPLS extensions only for some ICMP types. 595 */ 596 if (ndo->ndo_vflag >= 1 && plen > ICMP_EXTD_MINLEN && ICMP_MPLS_EXT_TYPE(dp->icmp_type)) { 597 598 ND_TCHECK(*ext_dp); 599 600 /* 601 * Check first if the mpls extension header shows a non-zero length. 602 * If the length field is not set then silently verify the checksum 603 * to check if an extension header is present. This is expedient, 604 * however not all implementations set the length field proper. 605 */ 606 if (!ext_dp->icmp_length) { 607 vec[0].ptr = (const uint8_t *)(void *)&ext_dp->icmp_ext_version_res; 608 vec[0].len = plen - ICMP_EXTD_MINLEN; 609 if (in_cksum(vec, 1)) { 610 return; 611 } 612 } 613 614 ND_PRINT((ndo, "\n\tMPLS extension v%u", 615 ICMP_MPLS_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res)))); 616 617 /* 618 * Sanity checking of the header. 619 */ 620 if (ICMP_MPLS_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res)) != 621 ICMP_MPLS_EXT_VERSION) { 622 ND_PRINT((ndo, " packet not supported")); 623 return; 624 } 625 626 hlen = plen - ICMP_EXTD_MINLEN; 627 vec[0].ptr = (const uint8_t *)(void *)&ext_dp->icmp_ext_version_res; 628 vec[0].len = hlen; 629 ND_PRINT((ndo, ", checksum 0x%04x (%scorrect), length %u", 630 EXTRACT_16BITS(ext_dp->icmp_ext_checksum), 631 in_cksum(vec, 1) ? "in" : "", 632 hlen)); 633 634 hlen -= 4; /* subtract common header size */ 635 obj_tptr = (uint8_t *)ext_dp->icmp_ext_data; 636 637 while (hlen > sizeof(struct icmp_mpls_ext_object_header_t)) { 638 639 icmp_mpls_ext_object_header = (struct icmp_mpls_ext_object_header_t *)obj_tptr; 640 ND_TCHECK(*icmp_mpls_ext_object_header); 641 obj_tlen = EXTRACT_16BITS(icmp_mpls_ext_object_header->length); 642 obj_class_num = icmp_mpls_ext_object_header->class_num; 643 obj_ctype = icmp_mpls_ext_object_header->ctype; 644 obj_tptr += sizeof(struct icmp_mpls_ext_object_header_t); 645 646 ND_PRINT((ndo, "\n\t %s Object (%u), Class-Type: %u, length %u", 647 tok2str(icmp_mpls_ext_obj_values,"unknown",obj_class_num), 648 obj_class_num, 649 obj_ctype, 650 obj_tlen)); 651 652 hlen-=sizeof(struct icmp_mpls_ext_object_header_t); /* length field includes tlv header */ 653 654 /* infinite loop protection */ 655 if ((obj_class_num == 0) || 656 (obj_tlen < sizeof(struct icmp_mpls_ext_object_header_t))) { 657 return; 658 } 659 obj_tlen-=sizeof(struct icmp_mpls_ext_object_header_t); 660 661 switch (obj_class_num) { 662 case 1: 663 switch(obj_ctype) { 664 case 1: 665 ND_TCHECK2(*obj_tptr, 4); 666 raw_label = EXTRACT_32BITS(obj_tptr); 667 ND_PRINT((ndo, "\n\t label %u, exp %u", MPLS_LABEL(raw_label), MPLS_EXP(raw_label))); 668 if (MPLS_STACK(raw_label)) 669 ND_PRINT((ndo, ", [S]")); 670 ND_PRINT((ndo, ", ttl %u", MPLS_TTL(raw_label))); 671 break; 672 default: 673 print_unknown_data(ndo, obj_tptr, "\n\t ", obj_tlen); 674 } 675 break; 676 677 /* 678 * FIXME those are the defined objects that lack a decoder 679 * you are welcome to contribute code ;-) 680 */ 681 case 2: 682 default: 683 print_unknown_data(ndo, obj_tptr, "\n\t ", obj_tlen); 684 break; 685 } 686 if (hlen < obj_tlen) 687 break; 688 hlen -= obj_tlen; 689 obj_tptr += obj_tlen; 690 } 691 } 692 693 return; 694 trunc: 695 ND_PRINT((ndo, "[|icmp]")); 696 } 697 /* 698 * Local Variables: 699 * c-style: whitesmith 700 * c-basic-offset: 8 701 * End: 702 */ 703
Indexes created Wed Jul 01 00:25:26 UTC 2026