print-icmp.c revision 1.5
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 1.5 2014/11/20 03:05:03 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_INFOTYPE(type) \ 154 ((type) == ICMP_ECHOREPLY || (type) == ICMP_ECHO || \ 155 (type) == ICMP_ROUTERADVERT || (type) == ICMP_ROUTERSOLICIT || \ 156 (type) == ICMP_TSTAMP || (type) == ICMP_TSTAMPREPLY || \ 157 (type) == ICMP_IREQ || (type) == ICMP_IREQREPLY || \ 158 (type) == ICMP_MASKREQ || (type) == ICMP_MASKREPLY) 159 #define ICMP_MPLS_EXT_TYPE(type) \ 160 ((type) == ICMP_UNREACH || \ 161 (type) == ICMP_TIMXCEED || \ 162 (type) == ICMP_PARAMPROB) 163 /* rfc1700 */ 164 #ifndef ICMP_UNREACH_NET_UNKNOWN 165 #define ICMP_UNREACH_NET_UNKNOWN 6 /* destination net unknown */ 166 #endif 167 #ifndef ICMP_UNREACH_HOST_UNKNOWN 168 #define ICMP_UNREACH_HOST_UNKNOWN 7 /* destination host unknown */ 169 #endif 170 #ifndef ICMP_UNREACH_ISOLATED 171 #define ICMP_UNREACH_ISOLATED 8 /* source host isolated */ 172 #endif 173 #ifndef ICMP_UNREACH_NET_PROHIB 174 #define ICMP_UNREACH_NET_PROHIB 9 /* admin prohibited net */ 175 #endif 176 #ifndef ICMP_UNREACH_HOST_PROHIB 177 #define ICMP_UNREACH_HOST_PROHIB 10 /* admin prohibited host */ 178 #endif 179 #ifndef ICMP_UNREACH_TOSNET 180 #define ICMP_UNREACH_TOSNET 11 /* tos prohibited net */ 181 #endif 182 #ifndef ICMP_UNREACH_TOSHOST 183 #define ICMP_UNREACH_TOSHOST 12 /* tos prohibited host */ 184 #endif 185 186 /* rfc1716 */ 187 #ifndef ICMP_UNREACH_FILTER_PROHIB 188 #define ICMP_UNREACH_FILTER_PROHIB 13 /* admin prohibited filter */ 189 #endif 190 #ifndef ICMP_UNREACH_HOST_PRECEDENCE 191 #define ICMP_UNREACH_HOST_PRECEDENCE 14 /* host precedence violation */ 192 #endif 193 #ifndef ICMP_UNREACH_PRECEDENCE_CUTOFF 194 #define ICMP_UNREACH_PRECEDENCE_CUTOFF 15 /* precedence cutoff */ 195 #endif 196 197 /* Most of the icmp types */ 198 static const struct tok icmp2str[] = { 199 { ICMP_ECHOREPLY, "echo reply" }, 200 { ICMP_SOURCEQUENCH, "source quench" }, 201 { ICMP_ECHO, "echo request" }, 202 { ICMP_ROUTERSOLICIT, "router solicitation" }, 203 { ICMP_TSTAMP, "time stamp request" }, 204 { ICMP_TSTAMPREPLY, "time stamp reply" }, 205 { ICMP_IREQ, "information request" }, 206 { ICMP_IREQREPLY, "information reply" }, 207 { ICMP_MASKREQ, "address mask request" }, 208 { 0, NULL } 209 }; 210 211 /* Formats for most of the ICMP_UNREACH codes */ 212 static const struct tok unreach2str[] = { 213 { ICMP_UNREACH_NET, "net %s unreachable" }, 214 { ICMP_UNREACH_HOST, "host %s unreachable" }, 215 { ICMP_UNREACH_SRCFAIL, 216 "%s unreachable - source route failed" }, 217 { ICMP_UNREACH_NET_UNKNOWN, "net %s unreachable - unknown" }, 218 { ICMP_UNREACH_HOST_UNKNOWN, "host %s unreachable - unknown" }, 219 { ICMP_UNREACH_ISOLATED, 220 "%s unreachable - source host isolated" }, 221 { ICMP_UNREACH_NET_PROHIB, 222 "net %s unreachable - admin prohibited" }, 223 { ICMP_UNREACH_HOST_PROHIB, 224 "host %s unreachable - admin prohibited" }, 225 { ICMP_UNREACH_TOSNET, 226 "net %s unreachable - tos prohibited" }, 227 { ICMP_UNREACH_TOSHOST, 228 "host %s unreachable - tos prohibited" }, 229 { ICMP_UNREACH_FILTER_PROHIB, 230 "host %s unreachable - admin prohibited filter" }, 231 { ICMP_UNREACH_HOST_PRECEDENCE, 232 "host %s unreachable - host precedence violation" }, 233 { ICMP_UNREACH_PRECEDENCE_CUTOFF, 234 "host %s unreachable - precedence cutoff" }, 235 { 0, NULL } 236 }; 237 238 /* Formats for the ICMP_REDIRECT codes */ 239 static const struct tok type2str[] = { 240 { ICMP_REDIRECT_NET, "redirect %s to net %s" }, 241 { ICMP_REDIRECT_HOST, "redirect %s to host %s" }, 242 { ICMP_REDIRECT_TOSNET, "redirect-tos %s to net %s" }, 243 { ICMP_REDIRECT_TOSHOST, "redirect-tos %s to host %s" }, 244 { 0, NULL } 245 }; 246 247 /* rfc1191 */ 248 struct mtu_discovery { 249 uint16_t unused; 250 uint16_t nexthopmtu; 251 }; 252 253 /* rfc1256 */ 254 struct ih_rdiscovery { 255 uint8_t ird_addrnum; 256 uint8_t ird_addrsiz; 257 uint16_t ird_lifetime; 258 }; 259 260 struct id_rdiscovery { 261 uint32_t ird_addr; 262 uint32_t ird_pref; 263 }; 264 265 /* 266 * draft-bonica-internet-icmp-08 267 * 268 * The Destination Unreachable, Time Exceeded 269 * and Parameter Problem messages are slighly changed as per 270 * the above draft. A new Length field gets added to give 271 * the caller an idea about the length of the piggypacked 272 * IP packet before the MPLS extension header starts. 273 * 274 * The Length field represents length of the padded "original datagram" 275 * field measured in 32-bit words. 276 * 277 * 0 1 2 3 278 * 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 1 279 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 280 * | Type | Code | Checksum | 281 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 282 * | unused | Length | unused | 283 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 284 * | Internet Header + leading octets of original datagram | 285 * | | 286 * | // | 287 * | | 288 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 289 */ 290 291 struct icmp_ext_t { 292 uint8_t icmp_type; 293 uint8_t icmp_code; 294 uint8_t icmp_checksum[2]; 295 uint8_t icmp_reserved; 296 uint8_t icmp_length; 297 uint8_t icmp_reserved2[2]; 298 uint8_t icmp_ext_legacy_header[128]; /* extension header starts 128 bytes after ICMP header */ 299 uint8_t icmp_ext_version_res[2]; 300 uint8_t icmp_ext_checksum[2]; 301 uint8_t icmp_ext_data[1]; 302 }; 303 304 struct icmp_mpls_ext_object_header_t { 305 uint8_t length[2]; 306 uint8_t class_num; 307 uint8_t ctype; 308 }; 309 310 static const struct tok icmp_mpls_ext_obj_values[] = { 311 { 1, "MPLS Stack Entry" }, 312 { 2, "Extended Payload" }, 313 { 0, NULL} 314 }; 315 316 /* prototypes */ 317 const char *icmp_tstamp_print(u_int); 318 319 /* print the milliseconds since midnight UTC */ 320 const char * 321 icmp_tstamp_print(u_int tstamp) { 322 u_int msec,sec,min,hrs; 323 324 static char buf[64]; 325 326 msec = tstamp % 1000; 327 sec = tstamp / 1000; 328 min = sec / 60; sec -= min * 60; 329 hrs = min / 60; min -= hrs * 60; 330 snprintf(buf, sizeof(buf), "%02u:%02u:%02u.%03u",hrs,min,sec,msec); 331 return buf; 332 } 333 334 void 335 icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *bp2, 336 int fragmented) 337 { 338 char *cp; 339 const struct icmp *dp; 340 const struct icmp_ext_t *ext_dp; 341 const struct ip *ip; 342 const char *str, *fmt; 343 const struct ip *oip; 344 const struct udphdr *ouh; 345 const uint8_t *obj_tptr; 346 uint32_t raw_label; 347 const u_char *snapend_save; 348 const struct icmp_mpls_ext_object_header_t *icmp_mpls_ext_object_header; 349 u_int hlen, dport, mtu, obj_tlen, obj_class_num, obj_ctype; 350 char buf[MAXHOSTNAMELEN + 100]; 351 struct cksum_vec vec[1]; 352 353 dp = (struct icmp *)bp; 354 ext_dp = (struct icmp_ext_t *)bp; 355 ip = (struct ip *)bp2; 356 str = buf; 357 358 ND_TCHECK(dp->icmp_code); 359 switch (dp->icmp_type) { 360 361 case ICMP_ECHO: 362 case ICMP_ECHOREPLY: 363 ND_TCHECK(dp->icmp_seq); 364 (void)snprintf(buf, sizeof(buf), "echo %s, id %u, seq %u", 365 dp->icmp_type == ICMP_ECHO ? 366 "request" : "reply", 367 EXTRACT_16BITS(&dp->icmp_id), 368 EXTRACT_16BITS(&dp->icmp_seq)); 369 break; 370 371 case ICMP_UNREACH: 372 ND_TCHECK(dp->icmp_ip.ip_dst); 373 switch (dp->icmp_code) { 374 375 case ICMP_UNREACH_PROTOCOL: 376 ND_TCHECK(dp->icmp_ip.ip_p); 377 (void)snprintf(buf, sizeof(buf), 378 "%s protocol %d unreachable", 379 ipaddr_string(ndo, &dp->icmp_ip.ip_dst), 380 dp->icmp_ip.ip_p); 381 break; 382 383 case ICMP_UNREACH_PORT: 384 ND_TCHECK(dp->icmp_ip.ip_p); 385 oip = &dp->icmp_ip; 386 hlen = IP_HL(oip) * 4; 387 ouh = (struct udphdr *)(((u_char *)oip) + hlen); 388 ND_TCHECK(ouh->uh_dport); 389 dport = EXTRACT_16BITS(&ouh->uh_dport); 390 switch (oip->ip_p) { 391 392 case IPPROTO_TCP: 393 (void)snprintf(buf, sizeof(buf), 394 "%s tcp port %s unreachable", 395 ipaddr_string(ndo, &oip->ip_dst), 396 tcpport_string(dport)); 397 break; 398 399 case IPPROTO_UDP: 400 (void)snprintf(buf, sizeof(buf), 401 "%s udp port %s unreachable", 402 ipaddr_string(ndo, &oip->ip_dst), 403 udpport_string(dport)); 404 break; 405 406 default: 407 (void)snprintf(buf, sizeof(buf), 408 "%s protocol %d port %d unreachable", 409 ipaddr_string(ndo, &oip->ip_dst), 410 oip->ip_p, dport); 411 break; 412 } 413 break; 414 415 case ICMP_UNREACH_NEEDFRAG: 416 { 417 register const struct mtu_discovery *mp; 418 mp = (struct mtu_discovery *)(u_char *)&dp->icmp_void; 419 mtu = EXTRACT_16BITS(&mp->nexthopmtu); 420 if (mtu) { 421 (void)snprintf(buf, sizeof(buf), 422 "%s unreachable - need to frag (mtu %d)", 423 ipaddr_string(ndo, &dp->icmp_ip.ip_dst), mtu); 424 } else { 425 (void)snprintf(buf, sizeof(buf), 426 "%s unreachable - need to frag", 427 ipaddr_string(ndo, &dp->icmp_ip.ip_dst)); 428 } 429 } 430 break; 431 432 default: 433 fmt = tok2str(unreach2str, "#%d %%s unreachable", 434 dp->icmp_code); 435 (void)snprintf(buf, sizeof(buf), fmt, 436 ipaddr_string(ndo, &dp->icmp_ip.ip_dst)); 437 break; 438 } 439 break; 440 441 case ICMP_REDIRECT: 442 ND_TCHECK(dp->icmp_ip.ip_dst); 443 fmt = tok2str(type2str, "redirect-#%d %%s to net %%s", 444 dp->icmp_code); 445 (void)snprintf(buf, sizeof(buf), fmt, 446 ipaddr_string(ndo, &dp->icmp_ip.ip_dst), 447 ipaddr_string(ndo, &dp->icmp_gwaddr)); 448 break; 449 450 case ICMP_ROUTERADVERT: 451 { 452 register const struct ih_rdiscovery *ihp; 453 register const struct id_rdiscovery *idp; 454 u_int lifetime, num, size; 455 456 (void)snprintf(buf, sizeof(buf), "router advertisement"); 457 cp = buf + strlen(buf); 458 459 ihp = (struct ih_rdiscovery *)&dp->icmp_void; 460 ND_TCHECK(*ihp); 461 (void)strncpy(cp, " lifetime ", sizeof(buf) - (cp - buf)); 462 cp = buf + strlen(buf); 463 lifetime = EXTRACT_16BITS(&ihp->ird_lifetime); 464 if (lifetime < 60) { 465 (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u", 466 lifetime); 467 } else if (lifetime < 60 * 60) { 468 (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u:%02u", 469 lifetime / 60, lifetime % 60); 470 } else { 471 (void)snprintf(cp, sizeof(buf) - (cp - buf), 472 "%u:%02u:%02u", 473 lifetime / 3600, 474 (lifetime % 3600) / 60, 475 lifetime % 60); 476 } 477 cp = buf + strlen(buf); 478 479 num = ihp->ird_addrnum; 480 (void)snprintf(cp, sizeof(buf) - (cp - buf), " %d:", num); 481 cp = buf + strlen(buf); 482 483 size = ihp->ird_addrsiz; 484 if (size != 2) { 485 (void)snprintf(cp, sizeof(buf) - (cp - buf), 486 " [size %d]", size); 487 break; 488 } 489 idp = (struct id_rdiscovery *)&dp->icmp_data; 490 while (num-- > 0) { 491 ND_TCHECK(*idp); 492 (void)snprintf(cp, sizeof(buf) - (cp - buf), " {%s %u}", 493 ipaddr_string(ndo, &idp->ird_addr), 494 EXTRACT_32BITS(&idp->ird_pref)); 495 cp = buf + strlen(buf); 496 ++idp; 497 } 498 } 499 break; 500 501 case ICMP_TIMXCEED: 502 ND_TCHECK(dp->icmp_ip.ip_dst); 503 switch (dp->icmp_code) { 504 505 case ICMP_TIMXCEED_INTRANS: 506 str = "time exceeded in-transit"; 507 break; 508 509 case ICMP_TIMXCEED_REASS: 510 str = "ip reassembly time exceeded"; 511 break; 512 513 default: 514 (void)snprintf(buf, sizeof(buf), "time exceeded-#%d", 515 dp->icmp_code); 516 break; 517 } 518 break; 519 520 case ICMP_PARAMPROB: 521 if (dp->icmp_code) 522 (void)snprintf(buf, sizeof(buf), 523 "parameter problem - code %d", dp->icmp_code); 524 else { 525 ND_TCHECK(dp->icmp_pptr); 526 (void)snprintf(buf, sizeof(buf), 527 "parameter problem - octet %d", dp->icmp_pptr); 528 } 529 break; 530 531 case ICMP_MASKREPLY: 532 ND_TCHECK(dp->icmp_mask); 533 (void)snprintf(buf, sizeof(buf), "address mask is 0x%08x", 534 EXTRACT_32BITS(&dp->icmp_mask)); 535 break; 536 537 case ICMP_TSTAMP: 538 ND_TCHECK(dp->icmp_seq); 539 (void)snprintf(buf, sizeof(buf), 540 "time stamp query id %u seq %u", 541 EXTRACT_16BITS(&dp->icmp_id), 542 EXTRACT_16BITS(&dp->icmp_seq)); 543 break; 544 545 case ICMP_TSTAMPREPLY: 546 ND_TCHECK(dp->icmp_ttime); 547 (void)snprintf(buf, sizeof(buf), 548 "time stamp reply id %u seq %u: org %s", 549 EXTRACT_16BITS(&dp->icmp_id), 550 EXTRACT_16BITS(&dp->icmp_seq), 551 icmp_tstamp_print(EXTRACT_32BITS(&dp->icmp_otime))); 552 553 (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", recv %s", 554 icmp_tstamp_print(EXTRACT_32BITS(&dp->icmp_rtime))); 555 (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", xmit %s", 556 icmp_tstamp_print(EXTRACT_32BITS(&dp->icmp_ttime))); 557 break; 558 559 default: 560 str = tok2str(icmp2str, "type-#%d", dp->icmp_type); 561 break; 562 } 563 ND_PRINT((ndo, "ICMP %s, length %u", str, plen)); 564 if (ndo->ndo_vflag && !fragmented) { /* don't attempt checksumming if this is a frag */ 565 uint16_t sum, icmp_sum; 566 struct cksum_vec vec[1]; 567 if (ND_TTEST2(*bp, plen)) { 568 vec[0].ptr = (const uint8_t *)(void *)dp; 569 vec[0].len = plen; 570 sum = in_cksum(vec, 1); 571 if (sum != 0) { 572 icmp_sum = EXTRACT_16BITS(&dp->icmp_cksum); 573 ND_PRINT((ndo, " (wrong icmp cksum %x (->%x)!)", 574 icmp_sum, 575 in_cksum_shouldbe(icmp_sum, sum))); 576 } 577 } 578 } 579 580 /* 581 * print the remnants of the IP packet. 582 * save the snaplength as this may get overidden in the IP printer. 583 */ 584 if (ndo->ndo_vflag >= 1 && !ICMP_INFOTYPE(dp->icmp_type)) { 585 bp += 8; 586 ND_PRINT((ndo, "\n\t")); 587 ip = (struct ip *)bp; 588 ndo->ndo_snaplen = ndo->ndo_snapend - bp; 589 snapend_save = ndo->ndo_snapend; 590 ip_print(ndo, bp, EXTRACT_16BITS(&ip->ip_len)); 591 ndo->ndo_snapend = snapend_save; 592 } 593 594 /* 595 * Attempt to decode the MPLS extensions only for some ICMP types. 596 */ 597 if (ndo->ndo_vflag >= 1 && plen > ICMP_EXTD_MINLEN && ICMP_MPLS_EXT_TYPE(dp->icmp_type)) { 598 599 ND_TCHECK(*ext_dp); 600 601 /* 602 * Check first if the mpls extension header shows a non-zero length. 603 * If the length field is not set then silently verify the checksum 604 * to check if an extension header is present. This is expedient, 605 * however not all implementations set the length field proper. 606 */ 607 if (!ext_dp->icmp_length) { 608 vec[0].ptr = (const uint8_t *)(void *)&ext_dp->icmp_ext_version_res; 609 vec[0].len = plen - ICMP_EXTD_MINLEN; 610 if (in_cksum(vec, 1)) { 611 return; 612 } 613 } 614 615 ND_PRINT((ndo, "\n\tMPLS extension v%u", 616 ICMP_MPLS_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res)))); 617 618 /* 619 * Sanity checking of the header. 620 */ 621 if (ICMP_MPLS_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res)) != 622 ICMP_MPLS_EXT_VERSION) { 623 ND_PRINT((ndo, " packet not supported")); 624 return; 625 } 626 627 hlen = plen - ICMP_EXTD_MINLEN; 628 vec[0].ptr = (const uint8_t *)(void *)&ext_dp->icmp_ext_version_res; 629 vec[0].len = hlen; 630 ND_PRINT((ndo, ", checksum 0x%04x (%scorrect), length %u", 631 EXTRACT_16BITS(ext_dp->icmp_ext_checksum), 632 in_cksum(vec, 1) ? "in" : "", 633 hlen)); 634 635 hlen -= 4; /* subtract common header size */ 636 obj_tptr = (uint8_t *)ext_dp->icmp_ext_data; 637 638 while (hlen > sizeof(struct icmp_mpls_ext_object_header_t)) { 639 640 icmp_mpls_ext_object_header = (struct icmp_mpls_ext_object_header_t *)obj_tptr; 641 ND_TCHECK(*icmp_mpls_ext_object_header); 642 obj_tlen = EXTRACT_16BITS(icmp_mpls_ext_object_header->length); 643 obj_class_num = icmp_mpls_ext_object_header->class_num; 644 obj_ctype = icmp_mpls_ext_object_header->ctype; 645 obj_tptr += sizeof(struct icmp_mpls_ext_object_header_t); 646 647 ND_PRINT((ndo, "\n\t %s Object (%u), Class-Type: %u, length %u", 648 tok2str(icmp_mpls_ext_obj_values,"unknown",obj_class_num), 649 obj_class_num, 650 obj_ctype, 651 obj_tlen)); 652 653 hlen-=sizeof(struct icmp_mpls_ext_object_header_t); /* length field includes tlv header */ 654 655 /* infinite loop protection */ 656 if ((obj_class_num == 0) || 657 (obj_tlen < sizeof(struct icmp_mpls_ext_object_header_t))) { 658 return; 659 } 660 obj_tlen-=sizeof(struct icmp_mpls_ext_object_header_t); 661 662 switch (obj_class_num) { 663 case 1: 664 switch(obj_ctype) { 665 case 1: 666 ND_TCHECK2(*obj_tptr, 4); 667 raw_label = EXTRACT_32BITS(obj_tptr); 668 ND_PRINT((ndo, "\n\t label %u, exp %u", MPLS_LABEL(raw_label), MPLS_EXP(raw_label))); 669 if (MPLS_STACK(raw_label)) 670 ND_PRINT((ndo, ", [S]")); 671 ND_PRINT((ndo, ", ttl %u", MPLS_TTL(raw_label))); 672 break; 673 default: 674 print_unknown_data(ndo, obj_tptr, "\n\t ", obj_tlen); 675 } 676 break; 677 678 /* 679 * FIXME those are the defined objects that lack a decoder 680 * you are welcome to contribute code ;-) 681 */ 682 case 2: 683 default: 684 print_unknown_data(ndo, obj_tptr, "\n\t ", obj_tlen); 685 break; 686 } 687 if (hlen < obj_tlen) 688 break; 689 hlen -= obj_tlen; 690 obj_tptr += obj_tlen; 691 } 692 } 693 694 return; 695 trunc: 696 ND_PRINT((ndo, "[|icmp]")); 697 } 698 /* 699 * Local Variables: 700 * c-style: whitesmith 701 * c-basic-offset: 8 702 * End: 703 */ 704
Indexes created Mon Jun 29 00:24:49 UTC 2026