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/* \summary: Internet Control Message Protocol (ICMP) printer */ 23 24#ifdef HAVE_CONFIG_H 25#include <config.h> 26#endif 27 28#include "netdissect-stdinc.h" 29 30#include <stdio.h> 31#include <string.h> 32 33#include "netdissect.h" 34#include "addrtoname.h" 35#include "extract.h" 36 37#include "ip.h" 38#include "udp.h" 39#include "ipproto.h" 40#include "mpls.h" 41 42/* 43 * Interface Control Message Protocol Definitions. 44 * Per RFC 792, September 1981. 45 */ 46 47/* 48 * Structure of an icmp header. 49 */ 50struct icmp { 51 nd_uint8_t icmp_type; /* type of message, see below */ 52 nd_uint8_t icmp_code; /* type sub code */ 53 nd_uint16_t icmp_cksum; /* ones complement cksum of struct */ 54 union { 55 nd_uint8_t ih_pptr; /* ICMP_PARAMPROB */ 56 nd_ipv4 ih_gwaddr; /* ICMP_REDIRECT */ 57 struct ih_idseq { 58 nd_uint16_t icd_id; 59 nd_uint16_t icd_seq; 60 } ih_idseq; 61 nd_uint32_t ih_void; 62 } icmp_hun; 63#define icmp_pptr icmp_hun.ih_pptr 64#define icmp_gwaddr icmp_hun.ih_gwaddr 65#define icmp_id icmp_hun.ih_idseq.icd_id 66#define icmp_seq icmp_hun.ih_idseq.icd_seq 67#define icmp_void icmp_hun.ih_void 68 union { 69 struct id_ts { 70 nd_uint32_t its_otime; 71 nd_uint32_t its_rtime; 72 nd_uint32_t its_ttime; 73 } id_ts; 74 struct id_ip { 75 struct ip idi_ip; 76 /* options and then 64 bits of data */ 77 } id_ip; 78 nd_uint32_t id_mask; 79 nd_byte id_data[1]; 80 } icmp_dun; 81#define icmp_otime icmp_dun.id_ts.its_otime 82#define icmp_rtime icmp_dun.id_ts.its_rtime 83#define icmp_ttime icmp_dun.id_ts.its_ttime 84#define icmp_ip icmp_dun.id_ip.idi_ip 85#define icmp_mask icmp_dun.id_mask 86#define icmp_data icmp_dun.id_data 87}; 88 89/* 90 * Lower bounds on packet lengths for various types. 91 * For the error advice packets must first insure that the 92 * packet is large enough to contain the returned ip header. 93 * Only then can we do the check to see if 64 bits of packet 94 * data have been returned, since we need to check the returned 95 * ip header length. 96 */ 97#define ICMP_MINLEN 8 /* abs minimum */ 98#define ICMP_EXTD_MINLEN (156 - sizeof (struct ip)) /* draft-bonica-internet-icmp-08 */ 99#define ICMP_TSLEN (8 + 3 * sizeof (uint32_t)) /* timestamp */ 100#define ICMP_MASKLEN 12 /* address mask */ 101#define ICMP_ADVLENMIN (8 + sizeof (struct ip) + 8) /* min */ 102#define ICMP_ADVLEN(p) (8 + (IP_HL(&(p)->icmp_ip) << 2) + 8) 103 /* N.B.: must separately check that ip_hl >= 5 */ 104 105/* 106 * Definition of type and code field values. 107 */ 108#define ICMP_ECHOREPLY 0 /* echo reply */ 109#define ICMP_UNREACH 3 /* dest unreachable, codes: */ 110#define ICMP_UNREACH_NET 0 /* bad net */ 111#define ICMP_UNREACH_HOST 1 /* bad host */ 112#define ICMP_UNREACH_PROTOCOL 2 /* bad protocol */ 113#define ICMP_UNREACH_PORT 3 /* bad port */ 114#define ICMP_UNREACH_NEEDFRAG 4 /* IP_DF caused drop */ 115#define ICMP_UNREACH_SRCFAIL 5 /* src route failed */ 116#define ICMP_UNREACH_NET_UNKNOWN 6 /* unknown net */ 117#define ICMP_UNREACH_HOST_UNKNOWN 7 /* unknown host */ 118#define ICMP_UNREACH_ISOLATED 8 /* src host isolated */ 119#define ICMP_UNREACH_NET_PROHIB 9 /* prohibited access */ 120#define ICMP_UNREACH_HOST_PROHIB 10 /* ditto */ 121#define ICMP_UNREACH_TOSNET 11 /* bad tos for net */ 122#define ICMP_UNREACH_TOSHOST 12 /* bad tos for host */ 123#define ICMP_SOURCEQUENCH 4 /* packet lost, slow down */ 124#define ICMP_REDIRECT 5 /* shorter route, codes: */ 125#define ICMP_REDIRECT_NET 0 /* for network */ 126#define ICMP_REDIRECT_HOST 1 /* for host */ 127#define ICMP_REDIRECT_TOSNET 2 /* for tos and net */ 128#define ICMP_REDIRECT_TOSHOST 3 /* for tos and host */ 129#define ICMP_ECHO 8 /* echo service */ 130#define ICMP_ROUTERADVERT 9 /* router advertisement */ 131#define ICMP_ROUTERSOLICIT 10 /* router solicitation */ 132#define ICMP_TIMXCEED 11 /* time exceeded, code: */ 133#define ICMP_TIMXCEED_INTRANS 0 /* ttl==0 in transit */ 134#define ICMP_TIMXCEED_REASS 1 /* ttl==0 in reass */ 135#define ICMP_PARAMPROB 12 /* ip header bad */ 136#define ICMP_PARAMPROB_OPTABSENT 1 /* req. opt. absent */ 137#define ICMP_TSTAMP 13 /* timestamp request */ 138#define ICMP_TSTAMPREPLY 14 /* timestamp reply */ 139#define ICMP_IREQ 15 /* information request */ 140#define ICMP_IREQREPLY 16 /* information reply */ 141#define ICMP_MASKREQ 17 /* address mask request */ 142#define ICMP_MASKREPLY 18 /* address mask reply */ 143 144#define ICMP_MAXTYPE 18 145 146#define ICMP_ERRTYPE(type) \ 147 ((type) == ICMP_UNREACH || (type) == ICMP_SOURCEQUENCH || \ 148 (type) == ICMP_REDIRECT || (type) == ICMP_TIMXCEED || \ 149 (type) == ICMP_PARAMPROB) 150#define ICMP_MULTIPART_EXT_TYPE(type) \ 151 ((type) == ICMP_UNREACH || \ 152 (type) == ICMP_TIMXCEED || \ 153 (type) == ICMP_PARAMPROB) 154/* rfc1700 */ 155#ifndef ICMP_UNREACH_NET_UNKNOWN 156#define ICMP_UNREACH_NET_UNKNOWN 6 /* destination net unknown */ 157#endif 158#ifndef ICMP_UNREACH_HOST_UNKNOWN 159#define ICMP_UNREACH_HOST_UNKNOWN 7 /* destination host unknown */ 160#endif 161#ifndef ICMP_UNREACH_ISOLATED 162#define ICMP_UNREACH_ISOLATED 8 /* source host isolated */ 163#endif 164#ifndef ICMP_UNREACH_NET_PROHIB 165#define ICMP_UNREACH_NET_PROHIB 9 /* admin prohibited net */ 166#endif 167#ifndef ICMP_UNREACH_HOST_PROHIB 168#define ICMP_UNREACH_HOST_PROHIB 10 /* admin prohibited host */ 169#endif 170#ifndef ICMP_UNREACH_TOSNET 171#define ICMP_UNREACH_TOSNET 11 /* tos prohibited net */ 172#endif 173#ifndef ICMP_UNREACH_TOSHOST 174#define ICMP_UNREACH_TOSHOST 12 /* tos prohibited host */ 175#endif 176 177/* rfc1716 */ 178#ifndef ICMP_UNREACH_FILTER_PROHIB 179#define ICMP_UNREACH_FILTER_PROHIB 13 /* admin prohibited filter */ 180#endif 181#ifndef ICMP_UNREACH_HOST_PRECEDENCE 182#define ICMP_UNREACH_HOST_PRECEDENCE 14 /* host precedence violation */ 183#endif 184#ifndef ICMP_UNREACH_PRECEDENCE_CUTOFF 185#define ICMP_UNREACH_PRECEDENCE_CUTOFF 15 /* precedence cutoff */ 186#endif 187 188/* Most of the icmp types */ 189static const struct tok icmp2str[] = { 190 { ICMP_ECHOREPLY, "echo reply" }, 191 { ICMP_SOURCEQUENCH, "source quench" }, 192 { ICMP_ECHO, "echo request" }, 193 { ICMP_ROUTERSOLICIT, "router solicitation" }, 194 { ICMP_TSTAMP, "time stamp request" }, 195 { ICMP_TSTAMPREPLY, "time stamp reply" }, 196 { ICMP_IREQ, "information request" }, 197 { ICMP_IREQREPLY, "information reply" }, 198 { ICMP_MASKREQ, "address mask request" }, 199 { 0, NULL } 200}; 201 202/* rfc1191 */ 203struct mtu_discovery { 204 nd_uint16_t unused; 205 nd_uint16_t nexthopmtu; 206}; 207 208/* rfc1256 */ 209struct ih_rdiscovery { 210 nd_uint8_t ird_addrnum; 211 nd_uint8_t ird_addrsiz; 212 nd_uint16_t ird_lifetime; 213}; 214 215struct id_rdiscovery { 216 nd_uint32_t ird_addr; 217 nd_uint32_t ird_pref; 218}; 219 220/* 221 * RFC 4884 - Extended ICMP to Support Multi-Part Messages 222 * 223 * This is a general extension mechanism, based on the mechanism 224 * in draft-bonica-icmp-mpls-02 ICMP Extensions for MultiProtocol 225 * Label Switching. 226 * 227 * The Destination Unreachable, Time Exceeded 228 * and Parameter Problem messages are slightly changed as per 229 * the above RFC. A new Length field gets added to give 230 * the caller an idea about the length of the piggybacked 231 * IP packet before the extension header starts. 232 * 233 * The Length field represents length of the padded "original datagram" 234 * field measured in 32-bit words. 235 * 236 * 0 1 2 3 237 * 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 1 238 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 239 * | Type | Code | Checksum | 240 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 241 * | unused | Length | unused | 242 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 243 * | Internet Header + leading octets of original datagram | 244 * | | 245 * | // | 246 * | | 247 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 248 */ 249 250struct icmp_ext_t { 251 nd_uint8_t icmp_type; 252 nd_uint8_t icmp_code; 253 nd_uint16_t icmp_checksum; 254 nd_byte icmp_reserved; 255 nd_uint8_t icmp_length; 256 nd_byte icmp_reserved2[2]; 257 nd_byte icmp_ext_legacy_header[128]; /* extension header starts 128 bytes after ICMP header */ 258 nd_byte icmp_ext_version_res[2]; 259 nd_uint16_t icmp_ext_checksum; 260 nd_byte icmp_ext_data[1]; 261}; 262 263/* 264 * Extract version from the first octet of icmp_ext_version_res. 265 */ 266#define ICMP_EXT_EXTRACT_VERSION(x) (((x)&0xf0)>>4) 267 268/* 269 * Current version. 270 */ 271#define ICMP_EXT_VERSION 2 272 273/* 274 * Extension object class numbers. 275 * 276 * Class 1 dates back to draft-bonica-icmp-mpls-02. 277 */ 278 279/* rfc4950 */ 280#define MPLS_STACK_ENTRY_OBJECT_CLASS 1 281 282struct icmp_multipart_ext_object_header_t { 283 nd_uint16_t length; 284 nd_uint8_t class_num; 285 nd_uint8_t ctype; 286}; 287 288static const struct tok icmp_multipart_ext_obj_values[] = { 289 { 1, "MPLS Stack Entry" }, 290 { 2, "Interface Identification" }, 291 { 0, NULL} 292}; 293 294/* prototypes */ 295const char *icmp_tstamp_print(u_int); 296 297/* print the milliseconds since midnight UTC */ 298const char * 299icmp_tstamp_print(u_int tstamp) 300{ 301 u_int msec,sec,min,hrs; 302 303 static char buf[64]; 304 305 msec = tstamp % 1000; 306 sec = tstamp / 1000; 307 min = sec / 60; sec -= min * 60; 308 hrs = min / 60; min -= hrs * 60; 309 snprintf(buf, sizeof(buf), "%02u:%02u:%02u.%03u",hrs,min,sec,msec); 310 return buf; 311} 312 313void 314icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *bp2, 315 int fragmented) 316{ 317 char *cp; 318 const struct icmp *dp; 319 uint8_t icmp_type, icmp_code; 320 const struct icmp_ext_t *ext_dp; 321 const struct ip *ip; 322 const char *str; 323 const struct ip *oip; 324 uint8_t ip_proto; 325 const struct udphdr *ouh; 326 const uint8_t *obj_tptr; 327 uint32_t raw_label; 328 const struct icmp_multipart_ext_object_header_t *icmp_multipart_ext_object_header; 329 u_int hlen, mtu, obj_tlen, obj_class_num, obj_ctype; 330 uint16_t dport; 331 char buf[MAXHOSTNAMELEN + 100]; 332 struct cksum_vec vec[1]; 333 334 ndo->ndo_protocol = "icmp"; 335 dp = (const struct icmp *)bp; 336 ext_dp = (const struct icmp_ext_t *)bp; 337 ip = (const struct ip *)bp2; 338 str = buf; 339 340 icmp_type = GET_U_1(dp->icmp_type); 341 icmp_code = GET_U_1(dp->icmp_code); 342 switch (icmp_type) { 343 344 case ICMP_ECHO: 345 case ICMP_ECHOREPLY: 346 (void)snprintf(buf, sizeof(buf), "echo %s, id %u, seq %u", 347 icmp_type == ICMP_ECHO ? 348 "request" : "reply", 349 GET_BE_U_2(dp->icmp_id), 350 GET_BE_U_2(dp->icmp_seq)); 351 break; 352 353 case ICMP_UNREACH: 354 switch (icmp_code) { 355 356 case ICMP_UNREACH_NET: 357 (void)snprintf(buf, sizeof(buf), 358 "net %s unreachable", 359 GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); 360 break; 361 362 case ICMP_UNREACH_HOST: 363 (void)snprintf(buf, sizeof(buf), 364 "host %s unreachable", 365 GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); 366 break; 367 368 case ICMP_UNREACH_PROTOCOL: 369 (void)snprintf(buf, sizeof(buf), 370 "%s protocol %u unreachable", 371 GET_IPADDR_STRING(dp->icmp_ip.ip_dst), 372 GET_U_1(dp->icmp_ip.ip_p)); 373 break; 374 375 case ICMP_UNREACH_PORT: 376 ND_TCHECK_1(dp->icmp_ip.ip_p); 377 oip = &dp->icmp_ip; 378 hlen = IP_HL(oip) * 4; 379 ouh = (const struct udphdr *)(((const u_char *)oip) + hlen); 380 dport = GET_BE_U_2(ouh->uh_dport); 381 ip_proto = GET_U_1(oip->ip_p); 382 switch (ip_proto) { 383 384 case IPPROTO_TCP: 385 (void)snprintf(buf, sizeof(buf), 386 "%s tcp port %s unreachable", 387 GET_IPADDR_STRING(oip->ip_dst), 388 tcpport_string(ndo, dport)); 389 break; 390 391 case IPPROTO_UDP: 392 (void)snprintf(buf, sizeof(buf), 393 "%s udp port %s unreachable", 394 GET_IPADDR_STRING(oip->ip_dst), 395 udpport_string(ndo, dport)); 396 break; 397 398 default: 399 (void)snprintf(buf, sizeof(buf), 400 "%s protocol %u port %u unreachable", 401 GET_IPADDR_STRING(oip->ip_dst), 402 ip_proto, dport); 403 break; 404 } 405 break; 406 407 case ICMP_UNREACH_NEEDFRAG: 408 { 409 const struct mtu_discovery *mp; 410 mp = (const struct mtu_discovery *)(const u_char *)&dp->icmp_void; 411 mtu = GET_BE_U_2(mp->nexthopmtu); 412 if (mtu) { 413 (void)snprintf(buf, sizeof(buf), 414 "%s unreachable - need to frag (mtu %u)", 415 GET_IPADDR_STRING(dp->icmp_ip.ip_dst), mtu); 416 } else { 417 (void)snprintf(buf, sizeof(buf), 418 "%s unreachable - need to frag", 419 GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); 420 } 421 } 422 break; 423 424 case ICMP_UNREACH_SRCFAIL: 425 (void)snprintf(buf, sizeof(buf), 426 "%s unreachable - source route failed", 427 GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); 428 break; 429 430 case ICMP_UNREACH_NET_UNKNOWN: 431 (void)snprintf(buf, sizeof(buf), 432 "net %s unreachable - unknown", 433 GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); 434 break; 435 436 case ICMP_UNREACH_HOST_UNKNOWN: 437 (void)snprintf(buf, sizeof(buf), 438 "host %s unreachable - unknown", 439 GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); 440 break; 441 442 case ICMP_UNREACH_ISOLATED: 443 (void)snprintf(buf, sizeof(buf), 444 "%s unreachable - source host isolated", 445 GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); 446 break; 447 448 case ICMP_UNREACH_NET_PROHIB: 449 (void)snprintf(buf, sizeof(buf), 450 "net %s unreachable - admin prohibited", 451 GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); 452 break; 453 454 case ICMP_UNREACH_HOST_PROHIB: 455 (void)snprintf(buf, sizeof(buf), 456 "host %s unreachable - admin prohibited", 457 GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); 458 break; 459 460 case ICMP_UNREACH_TOSNET: 461 (void)snprintf(buf, sizeof(buf), 462 "net %s unreachable - tos prohibited", 463 GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); 464 break; 465 466 case ICMP_UNREACH_TOSHOST: 467 (void)snprintf(buf, sizeof(buf), 468 "host %s unreachable - tos prohibited", 469 GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); 470 break; 471 472 case ICMP_UNREACH_FILTER_PROHIB: 473 (void)snprintf(buf, sizeof(buf), 474 "host %s unreachable - admin prohibited filter", 475 GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); 476 break; 477 478 case ICMP_UNREACH_HOST_PRECEDENCE: 479 (void)snprintf(buf, sizeof(buf), 480 "host %s unreachable - host precedence violation", 481 GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); 482 break; 483 484 case ICMP_UNREACH_PRECEDENCE_CUTOFF: 485 (void)snprintf(buf, sizeof(buf), 486 "host %s unreachable - precedence cutoff", 487 GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); 488 break; 489 490 default: 491 (void)snprintf(buf, sizeof(buf), 492 "%s unreachable - #%u", 493 GET_IPADDR_STRING(dp->icmp_ip.ip_dst), 494 icmp_code); 495 break; 496 } 497 break; 498 499 case ICMP_REDIRECT: 500 switch (icmp_code) { 501 502 case ICMP_REDIRECT_NET: 503 (void)snprintf(buf, sizeof(buf), 504 "redirect %s to net %s", 505 GET_IPADDR_STRING(dp->icmp_ip.ip_dst), 506 GET_IPADDR_STRING(dp->icmp_gwaddr)); 507 break; 508 509 case ICMP_REDIRECT_HOST: 510 (void)snprintf(buf, sizeof(buf), 511 "redirect %s to host %s", 512 GET_IPADDR_STRING(dp->icmp_ip.ip_dst), 513 GET_IPADDR_STRING(dp->icmp_gwaddr)); 514 break; 515 516 case ICMP_REDIRECT_TOSNET: 517 (void)snprintf(buf, sizeof(buf), 518 "redirect-tos %s to net %s", 519 GET_IPADDR_STRING(dp->icmp_ip.ip_dst), 520 GET_IPADDR_STRING(dp->icmp_gwaddr)); 521 break; 522 523 case ICMP_REDIRECT_TOSHOST: 524 (void)snprintf(buf, sizeof(buf), 525 "redirect-tos %s to host %s", 526 GET_IPADDR_STRING(dp->icmp_ip.ip_dst), 527 GET_IPADDR_STRING(dp->icmp_gwaddr)); 528 break; 529 530 default: 531 (void)snprintf(buf, sizeof(buf), 532 "redirect-#%u %s to %s", icmp_code, 533 GET_IPADDR_STRING(dp->icmp_ip.ip_dst), 534 GET_IPADDR_STRING(dp->icmp_gwaddr)); 535 break; 536 } 537 break; 538 539 case ICMP_ROUTERADVERT: 540 { 541 const struct ih_rdiscovery *ihp; 542 const struct id_rdiscovery *idp; 543 u_int lifetime, num, size; 544 545 (void)snprintf(buf, sizeof(buf), "router advertisement"); 546 cp = buf + strlen(buf); 547 548 ihp = (const struct ih_rdiscovery *)&dp->icmp_void; 549 ND_TCHECK_SIZE(ihp); 550 (void)strncpy(cp, " lifetime ", sizeof(buf) - (cp - buf)); 551 cp = buf + strlen(buf); 552 lifetime = GET_BE_U_2(ihp->ird_lifetime); 553 if (lifetime < 60) { 554 (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u", 555 lifetime); 556 } else if (lifetime < 60 * 60) { 557 (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u:%02u", 558 lifetime / 60, lifetime % 60); 559 } else { 560 (void)snprintf(cp, sizeof(buf) - (cp - buf), 561 "%u:%02u:%02u", 562 lifetime / 3600, 563 (lifetime % 3600) / 60, 564 lifetime % 60); 565 } 566 cp = buf + strlen(buf); 567 568 num = GET_U_1(ihp->ird_addrnum); 569 (void)snprintf(cp, sizeof(buf) - (cp - buf), " %u:", num); 570 cp = buf + strlen(buf); 571 572 size = GET_U_1(ihp->ird_addrsiz); 573 if (size != 2) { 574 (void)snprintf(cp, sizeof(buf) - (cp - buf), 575 " [size %u]", size); 576 break; 577 } 578 idp = (const struct id_rdiscovery *)&dp->icmp_data; 579 while (num > 0) { 580 ND_TCHECK_SIZE(idp); 581 (void)snprintf(cp, sizeof(buf) - (cp - buf), " {%s %u}", 582 GET_IPADDR_STRING(idp->ird_addr), 583 GET_BE_U_4(idp->ird_pref)); 584 cp = buf + strlen(buf); 585 ++idp; 586 num--; 587 } 588 } 589 break; 590 591 case ICMP_TIMXCEED: 592 ND_TCHECK_4(dp->icmp_ip.ip_dst); 593 switch (icmp_code) { 594 595 case ICMP_TIMXCEED_INTRANS: 596 str = "time exceeded in-transit"; 597 break; 598 599 case ICMP_TIMXCEED_REASS: 600 str = "ip reassembly time exceeded"; 601 break; 602 603 default: 604 (void)snprintf(buf, sizeof(buf), "time exceeded-#%u", 605 icmp_code); 606 break; 607 } 608 break; 609 610 case ICMP_PARAMPROB: 611 if (icmp_code) 612 (void)snprintf(buf, sizeof(buf), 613 "parameter problem - code %u", icmp_code); 614 else { 615 (void)snprintf(buf, sizeof(buf), 616 "parameter problem - octet %u", 617 GET_U_1(dp->icmp_pptr)); 618 } 619 break; 620 621 case ICMP_MASKREPLY: 622 (void)snprintf(buf, sizeof(buf), "address mask is 0x%08x", 623 GET_BE_U_4(dp->icmp_mask)); 624 break; 625 626 case ICMP_TSTAMP: 627 (void)snprintf(buf, sizeof(buf), 628 "time stamp query id %u seq %u", 629 GET_BE_U_2(dp->icmp_id), 630 GET_BE_U_2(dp->icmp_seq)); 631 break; 632 633 case ICMP_TSTAMPREPLY: 634 ND_TCHECK_4(dp->icmp_ttime); 635 (void)snprintf(buf, sizeof(buf), 636 "time stamp reply id %u seq %u: org %s", 637 GET_BE_U_2(dp->icmp_id), 638 GET_BE_U_2(dp->icmp_seq), 639 icmp_tstamp_print(GET_BE_U_4(dp->icmp_otime))); 640 641 (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", recv %s", 642 icmp_tstamp_print(GET_BE_U_4(dp->icmp_rtime))); 643 (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", xmit %s", 644 icmp_tstamp_print(GET_BE_U_4(dp->icmp_ttime))); 645 break; 646 647 default: 648 str = tok2str(icmp2str, "type-#%u", icmp_type); 649 break; 650 } 651 ND_PRINT("ICMP %s, length %u", str, plen); 652 if (ndo->ndo_vflag && !fragmented) { /* don't attempt checksumming if this is a frag */ 653 if (ND_TTEST_LEN(bp, plen)) { 654 uint16_t sum; 655 656 vec[0].ptr = (const uint8_t *)(const void *)dp; 657 vec[0].len = plen; 658 sum = in_cksum(vec, 1); 659 if (sum != 0) { 660 uint16_t icmp_sum = GET_BE_U_2(dp->icmp_cksum); 661 ND_PRINT(" (wrong icmp cksum %x (->%x)!)", 662 icmp_sum, 663 in_cksum_shouldbe(icmp_sum, sum)); 664 } 665 } 666 } 667 668 /* 669 * print the remnants of the IP packet. 670 * save the snaplength as this may get overridden in the IP printer. 671 */ 672 if (ndo->ndo_vflag >= 1 && ICMP_ERRTYPE(icmp_type)) { 673 const u_char *snapend_save; 674 675 bp += 8; 676 ND_PRINT("\n\t"); 677 ip = (const struct ip *)bp; 678 snapend_save = ndo->ndo_snapend; 679 /* 680 * Update the snapend because extensions (MPLS, ...) may be 681 * present after the IP packet. In this case the current 682 * (outer) packet's snapend is not what ip_print() needs to 683 * decode an IP packet nested in the middle of an ICMP payload. 684 * 685 * This prevents that, in ip_print(), for the nested IP packet, 686 * the remaining length < remaining caplen. 687 */ 688 ndo->ndo_snapend = ND_MIN(bp + GET_BE_U_2(ip->ip_len), 689 ndo->ndo_snapend); 690 ip_print(ndo, bp, GET_BE_U_2(ip->ip_len)); 691 ndo->ndo_snapend = snapend_save; 692 } 693 694 /* ndo_protocol reassignment after ip_print() call */ 695 ndo->ndo_protocol = "icmp"; 696 697 /* 698 * Attempt to decode multi-part message extensions (rfc4884) only for some ICMP types. 699 */ 700 if (ndo->ndo_vflag >= 1 && plen > ICMP_EXTD_MINLEN && ICMP_MULTIPART_EXT_TYPE(icmp_type)) { 701 702 ND_TCHECK_SIZE(ext_dp); 703 704 /* 705 * Check first if the multi-part extension header shows a non-zero length. 706 * If the length field is not set then silently verify the checksum 707 * to check if an extension header is present. This is expedient, 708 * however not all implementations set the length field proper. 709 */ 710 if (GET_U_1(ext_dp->icmp_length) == 0 && 711 ND_TTEST_LEN(ext_dp->icmp_ext_version_res, plen - ICMP_EXTD_MINLEN)) { 712 vec[0].ptr = (const uint8_t *)(const void *)&ext_dp->icmp_ext_version_res; 713 vec[0].len = plen - ICMP_EXTD_MINLEN; 714 if (in_cksum(vec, 1)) { 715 return; 716 } 717 } 718 719 ND_PRINT("\n\tICMP Multi-Part extension v%u", 720 ICMP_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res))); 721 722 /* 723 * Sanity checking of the header. 724 */ 725 if (ICMP_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res)) != 726 ICMP_EXT_VERSION) { 727 ND_PRINT(" packet not supported"); 728 return; 729 } 730 731 hlen = plen - ICMP_EXTD_MINLEN; 732 if (ND_TTEST_LEN(ext_dp->icmp_ext_version_res, hlen)) { 733 vec[0].ptr = (const uint8_t *)(const void *)&ext_dp->icmp_ext_version_res; 734 vec[0].len = hlen; 735 ND_PRINT(", checksum 0x%04x (%scorrect), length %u", 736 GET_BE_U_2(ext_dp->icmp_ext_checksum), 737 in_cksum(vec, 1) ? "in" : "", 738 hlen); 739 } 740 741 hlen -= 4; /* subtract common header size */ 742 obj_tptr = (const uint8_t *)ext_dp->icmp_ext_data; 743 744 while (hlen > sizeof(struct icmp_multipart_ext_object_header_t)) { 745 746 icmp_multipart_ext_object_header = (const struct icmp_multipart_ext_object_header_t *)obj_tptr; 747 ND_TCHECK_SIZE(icmp_multipart_ext_object_header); 748 obj_tlen = GET_BE_U_2(icmp_multipart_ext_object_header->length); 749 obj_class_num = GET_U_1(icmp_multipart_ext_object_header->class_num); 750 obj_ctype = GET_U_1(icmp_multipart_ext_object_header->ctype); 751 obj_tptr += sizeof(struct icmp_multipart_ext_object_header_t); 752 753 ND_PRINT("\n\t %s Object (%u), Class-Type: %u, length %u", 754 tok2str(icmp_multipart_ext_obj_values,"unknown",obj_class_num), 755 obj_class_num, 756 obj_ctype, 757 obj_tlen); 758 759 hlen-=sizeof(struct icmp_multipart_ext_object_header_t); /* length field includes tlv header */ 760 761 /* infinite loop protection */ 762 if ((obj_class_num == 0) || 763 (obj_tlen < sizeof(struct icmp_multipart_ext_object_header_t))) { 764 return; 765 } 766 obj_tlen-=sizeof(struct icmp_multipart_ext_object_header_t); 767 768 switch (obj_class_num) { 769 case MPLS_STACK_ENTRY_OBJECT_CLASS: 770 switch(obj_ctype) { 771 case 1: 772 raw_label = GET_BE_U_4(obj_tptr); 773 ND_PRINT("\n\t label %u, tc %u", MPLS_LABEL(raw_label), MPLS_TC(raw_label)); 774 if (MPLS_STACK(raw_label)) 775 ND_PRINT(", [S]"); 776 ND_PRINT(", ttl %u", MPLS_TTL(raw_label)); 777 break; 778 default: 779 print_unknown_data(ndo, obj_tptr, "\n\t ", obj_tlen); 780 } 781 break; 782 783 default: 784 print_unknown_data(ndo, obj_tptr, "\n\t ", obj_tlen); 785 break; 786 } 787 if (hlen < obj_tlen) 788 break; 789 hlen -= obj_tlen; 790 obj_tptr += obj_tlen; 791 } 792 } 793 794 return; 795trunc: 796 nd_print_trunc(ndo); 797} 798