contrib/tcpdump/print-icmp.c

   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  * $FreeBSD$
  22  */
  23
  24 #ifndef lint
  25 static const char rcsid[] _U_ =
  26     "@(#) $Header: /tcpdump/master/tcpdump/print-icmp.c,v 1.81.2.2 2005/07/01 16:13:37 hannes Exp $ (LBL)";
  27 #endif
  28
  29 #ifdef HAVE_CONFIG_H
  30 #include "config.h"
  31 #endif
  32
  33 #include <tcpdump-stdinc.h>
  34
  35 #include <stdio.h>
  36 #include <string.h>
  37
  38 #include "interface.h"
  39 #include "addrtoname.h"
  40 #include "extract.h"                    /* must come after interface.h */
  41
  42 #include "ip.h"
  43 #include "udp.h"
  44 #include "ipproto.h"
  45 #include "mpls.h"
  46
  47 /*
  48  * Interface Control Message Protocol Definitions.
  49  * Per RFC 792, September 1981.
  50  */
  51
  52 /*
  53  * Structure of an icmp header.
  54  */
  55 struct icmp {
  56         u_int8_t  icmp_type;            /* type of message, see below */
  57         u_int8_t  icmp_code;            /* type sub code */
  58         u_int16_t icmp_cksum;           /* ones complement cksum of struct */
  59         union {
  60                 u_int8_t ih_pptr;                       /* ICMP_PARAMPROB */
  61                 struct in_addr ih_gwaddr;       /* ICMP_REDIRECT */
  62                 struct ih_idseq {
  63                         u_int16_t icd_id;
  64                         u_int16_t icd_seq;
  65                 } ih_idseq;
  66                 u_int32_t ih_void;
  67
  68                 /* ICMP_UNREACH_NEEDFRAG -- Path MTU Discovery (RFC1191) */
  69                 struct ih_pmtu {
  70                         u_int16_t ipm_void;
  71                         u_int16_t ipm_nextmtu;
  72                 } ih_pmtu;
  73         } icmp_hun;
  74 #define icmp_pptr       icmp_hun.ih_pptr
  75 #define icmp_gwaddr     icmp_hun.ih_gwaddr
  76 #define icmp_id         icmp_hun.ih_idseq.icd_id
  77 #define icmp_seq        icmp_hun.ih_idseq.icd_seq
  78 #define icmp_void       icmp_hun.ih_void
  79 #define icmp_pmvoid     icmp_hun.ih_pmtu.ipm_void
  80 #define icmp_nextmtu    icmp_hun.ih_pmtu.ipm_nextmtu
  81         union {
  82                 struct id_ts {
  83                         u_int32_t its_otime;
  84                         u_int32_t its_rtime;
  85                         u_int32_t its_ttime;
  86                 } id_ts;
  87                 struct id_ip  {
  88                         struct ip idi_ip;
  89                         /* options and then 64 bits of data */
  90                 } id_ip;
  91                 struct mpls_ext {
  92                     u_int8_t legacy_header[128]; /* extension header starts 128 bytes after ICMP header */
  93                     u_int8_t version_res[2];
  94                     u_int8_t checksum[2];
  95                     u_int8_t data[1];
  96                 } mpls_ext;
  97                 u_int32_t id_mask;
  98                 u_int8_t id_data[1];
  99         } icmp_dun;
 100 #define icmp_otime      icmp_dun.id_ts.its_otime
 101 #define icmp_rtime      icmp_dun.id_ts.its_rtime
 102 #define icmp_ttime      icmp_dun.id_ts.its_ttime
 103 #define icmp_ip         icmp_dun.id_ip.idi_ip
 104 #define icmp_mask       icmp_dun.id_mask
 105 #define icmp_data       icmp_dun.id_data
 106 #define icmp_mpls_ext_version   icmp_dun.mpls_ext.version_res
 107 #define icmp_mpls_ext_checksum  icmp_dun.mpls_ext.checksum
 108 #define icmp_mpls_ext_data      icmp_dun.mpls_ext.data
 109 };
 110
 111 #define ICMP_MPLS_EXT_EXTRACT_VERSION(x) (((x)&0xf0)>>4)
 112 #define ICMP_MPLS_EXT_VERSION 2
 113
 114 /*
 115  * Lower bounds on packet lengths for various types.
 116  * For the error advice packets must first insure that the
 117  * packet is large enought to contain the returned ip header.
 118  * Only then can we do the check to see if 64 bits of packet
 119  * data have been returned, since we need to check the returned
 120  * ip header length.
 121  */
 122 #define ICMP_MINLEN     8                               /* abs minimum */
 123 #define ICMP_EXTD_MINLEN (156 - sizeof (struct ip))     /* draft-bonica-icmp-mpls-02 */
 124 #define ICMP_TSLEN      (8 + 3 * sizeof (u_int32_t))    /* timestamp */
 125 #define ICMP_MASKLEN    12                              /* address mask */
 126 #define ICMP_ADVLENMIN  (8 + sizeof (struct ip) + 8)    /* min */
 127 #define ICMP_ADVLEN(p)  (8 + (IP_HL(&(p)->icmp_ip) << 2) + 8)
 128         /* N.B.: must separately check that ip_hl >= 5 */
 129
 130 /*
 131  * Definition of type and code field values.
 132  */
 133 #define ICMP_ECHOREPLY          0               /* echo reply */
 134 #define ICMP_UNREACH            3               /* dest unreachable, codes: */
 135 #define         ICMP_UNREACH_NET        0               /* bad net */
 136 #define         ICMP_UNREACH_HOST       1               /* bad host */
 137 #define         ICMP_UNREACH_PROTOCOL   2               /* bad protocol */
 138 #define         ICMP_UNREACH_PORT       3               /* bad port */
 139 #define         ICMP_UNREACH_NEEDFRAG   4               /* IP_DF caused drop */
 140 #define         ICMP_UNREACH_SRCFAIL    5               /* src route failed */
 141 #define         ICMP_UNREACH_NET_UNKNOWN 6              /* unknown net */
 142 #define         ICMP_UNREACH_HOST_UNKNOWN 7             /* unknown host */
 143 #define         ICMP_UNREACH_ISOLATED   8               /* src host isolated */
 144 #define         ICMP_UNREACH_NET_PROHIB 9               /* prohibited access */
 145 #define         ICMP_UNREACH_HOST_PROHIB 10             /* ditto */
 146 #define         ICMP_UNREACH_TOSNET     11              /* bad tos for net */
 147 #define         ICMP_UNREACH_TOSHOST    12              /* bad tos for host */
 148 #define ICMP_SOURCEQUENCH       4               /* packet lost, slow down */
 149 #define ICMP_REDIRECT           5               /* shorter route, codes: */
 150 #define         ICMP_REDIRECT_NET       0               /* for network */
 151 #define         ICMP_REDIRECT_HOST      1               /* for host */
 152 #define         ICMP_REDIRECT_TOSNET    2               /* for tos and net */
 153 #define         ICMP_REDIRECT_TOSHOST   3               /* for tos and host */
 154 #define ICMP_ECHO               8               /* echo service */
 155 #define ICMP_ROUTERADVERT       9               /* router advertisement */
 156 #define ICMP_ROUTERSOLICIT      10              /* router solicitation */
 157 #define ICMP_TIMXCEED           11              /* time exceeded, code: */
 158 #define         ICMP_TIMXCEED_INTRANS   0               /* ttl==0 in transit */
 159 #define         ICMP_TIMXCEED_REASS     1               /* ttl==0 in reass */
 160 #define ICMP_PARAMPROB          12              /* ip header bad */
 161 #define         ICMP_PARAMPROB_OPTABSENT 1              /* req. opt. absent */
 162 #define ICMP_TSTAMP             13              /* timestamp request */
 163 #define ICMP_TSTAMPREPLY        14              /* timestamp reply */
 164 #define ICMP_IREQ               15              /* information request */
 165 #define ICMP_IREQREPLY          16              /* information reply */
 166 #define ICMP_MASKREQ            17              /* address mask request */
 167 #define ICMP_MASKREPLY          18              /* address mask reply */
 168
 169 #define ICMP_MAXTYPE            18
 170
 171 #define ICMP_INFOTYPE(type) \
 172         ((type) == ICMP_ECHOREPLY || (type) == ICMP_ECHO || \
 173         (type) == ICMP_ROUTERADVERT || (type) == ICMP_ROUTERSOLICIT || \
 174         (type) == ICMP_TSTAMP || (type) == ICMP_TSTAMPREPLY || \
 175         (type) == ICMP_IREQ || (type) == ICMP_IREQREPLY || \
 176         (type) == ICMP_MASKREQ || (type) == ICMP_MASKREPLY)
 177 #define ICMP_MPLS_EXT_TYPE(type) \
 178         ((type) == ICMP_UNREACH || (type) == ICMP_TIMXCEED)
 179 /* rfc1700 */
 180 #ifndef ICMP_UNREACH_NET_UNKNOWN
 181 #define ICMP_UNREACH_NET_UNKNOWN        6       /* destination net unknown */
 182 #endif
 183 #ifndef ICMP_UNREACH_HOST_UNKNOWN
 184 #define ICMP_UNREACH_HOST_UNKNOWN       7       /* destination host unknown */
 185 #endif
 186 #ifndef ICMP_UNREACH_ISOLATED
 187 #define ICMP_UNREACH_ISOLATED           8       /* source host isolated */
 188 #endif
 189 #ifndef ICMP_UNREACH_NET_PROHIB
 190 #define ICMP_UNREACH_NET_PROHIB         9       /* admin prohibited net */
 191 #endif
 192 #ifndef ICMP_UNREACH_HOST_PROHIB
 193 #define ICMP_UNREACH_HOST_PROHIB        10      /* admin prohibited host */
 194 #endif
 195 #ifndef ICMP_UNREACH_TOSNET
 196 #define ICMP_UNREACH_TOSNET             11      /* tos prohibited net */
 197 #endif
 198 #ifndef ICMP_UNREACH_TOSHOST
 199 #define ICMP_UNREACH_TOSHOST            12      /* tos prohibited host */
 200 #endif
 201
 202 /* rfc1716 */
 203 #ifndef ICMP_UNREACH_FILTER_PROHIB
 204 #define ICMP_UNREACH_FILTER_PROHIB      13      /* admin prohibited filter */
 205 #endif
 206 #ifndef ICMP_UNREACH_HOST_PRECEDENCE
 207 #define ICMP_UNREACH_HOST_PRECEDENCE    14      /* host precedence violation */
 208 #endif
 209 #ifndef ICMP_UNREACH_PRECEDENCE_CUTOFF
 210 #define ICMP_UNREACH_PRECEDENCE_CUTOFF  15      /* precedence cutoff */
 211 #endif
 212
 213 /* Most of the icmp types */
 214 static struct tok icmp2str[] = {
 215         { ICMP_ECHOREPLY,               "echo reply" },
 216         { ICMP_SOURCEQUENCH,            "source quench" },
 217         { ICMP_ECHO,                    "echo request" },
 218         { ICMP_ROUTERSOLICIT,           "router solicitation" },
 219         { ICMP_TSTAMP,                  "time stamp request" },
 220         { ICMP_TSTAMPREPLY,             "time stamp reply" },
 221         { ICMP_IREQ,                    "information request" },
 222         { ICMP_IREQREPLY,               "information reply" },
 223         { ICMP_MASKREQ,                 "address mask request" },
 224         { 0,                            NULL }
 225 };
 226
 227 /* Formats for most of the ICMP_UNREACH codes */
 228 static struct tok unreach2str[] = {
 229         { ICMP_UNREACH_NET,             "net %s unreachable" },
 230         { ICMP_UNREACH_HOST,            "host %s unreachable" },
 231         { ICMP_UNREACH_SRCFAIL,
 232             "%s unreachable - source route failed" },
 233         { ICMP_UNREACH_NET_UNKNOWN,     "net %s unreachable - unknown" },
 234         { ICMP_UNREACH_HOST_UNKNOWN,    "host %s unreachable - unknown" },
 235         { ICMP_UNREACH_ISOLATED,
 236             "%s unreachable - source host isolated" },
 237         { ICMP_UNREACH_NET_PROHIB,
 238             "net %s unreachable - admin prohibited" },
 239         { ICMP_UNREACH_HOST_PROHIB,
 240             "host %s unreachable - admin prohibited" },
 241         { ICMP_UNREACH_TOSNET,
 242             "net %s unreachable - tos prohibited" },
 243         { ICMP_UNREACH_TOSHOST,
 244             "host %s unreachable - tos prohibited" },
 245         { ICMP_UNREACH_FILTER_PROHIB,
 246             "host %s unreachable - admin prohibited filter" },
 247         { ICMP_UNREACH_HOST_PRECEDENCE,
 248             "host %s unreachable - host precedence violation" },
 249         { ICMP_UNREACH_PRECEDENCE_CUTOFF,
 250             "host %s unreachable - precedence cutoff" },
 251         { 0,                            NULL }
 252 };
 253
 254 /* Formats for the ICMP_REDIRECT codes */
 255 static struct tok type2str[] = {
 256         { ICMP_REDIRECT_NET,            "redirect %s to net %s" },
 257         { ICMP_REDIRECT_HOST,           "redirect %s to host %s" },
 258         { ICMP_REDIRECT_TOSNET,         "redirect-tos %s to net %s" },
 259         { ICMP_REDIRECT_TOSHOST,        "redirect-tos %s to host %s" },
 260         { 0,                            NULL }
 261 };
 262
 263 /* rfc1191 */
 264 struct mtu_discovery {
 265         u_int16_t unused;
 266         u_int16_t nexthopmtu;
 267 };
 268
 269 /* rfc1256 */
 270 struct ih_rdiscovery {
 271         u_int8_t ird_addrnum;
 272         u_int8_t ird_addrsiz;
 273         u_int16_t ird_lifetime;
 274 };
 275
 276 struct id_rdiscovery {
 277         u_int32_t ird_addr;
 278         u_int32_t ird_pref;
 279 };
 280
 281 /* draft-bonica-icmp-mpls-02 */
 282 struct icmp_mpls_ext_object_header_t {
 283     u_int8_t length[2];
 284     u_int8_t class_num;
 285     u_int8_t ctype;
 286 };
 287
 288 static const struct tok icmp_mpls_ext_obj_values[] = {
 289     { 1, "MPLS Stack Entry" },
 290     { 2, "Extended Payload" },
 291     { 0, NULL}
 292 };
 293
 294 /* prototypes */
 295 const char *icmp_tstamp_print(u_int);
 296
 297 /* print the milliseconds since midnight UTC */
 298 const char *
 299 icmp_tstamp_print(u_int tstamp) {
 300     u_int msec,sec,min,hrs;
 301
 302     static char buf[64];
 303
 304     msec = tstamp % 1000;
 305     sec = tstamp / 1000;
 306     min = sec / 60; sec -= min * 60;
 307     hrs = min / 60; min -= hrs * 60;
 308     snprintf(buf, sizeof(buf), "%02u:%02u:%02u.%03u",hrs,min,sec,msec);
 309     return buf;
 310 }
 311
 312 void
 313 icmp_print(const u_char *bp, u_int plen, const u_char *bp2, int fragmented)
 314 {
 315         char *cp;
 316         const struct icmp *dp;
 317         const struct ip *ip;
 318         const char *str, *fmt;
 319         const struct ip *oip;
 320         const struct udphdr *ouh;
 321         const u_int8_t *obj_tptr;
 322         u_int32_t raw_label;
 323         const struct icmp_mpls_ext_object_header_t *icmp_mpls_ext_object_header;
 324         u_int hlen, dport, mtu, obj_tlen, obj_class_num, obj_ctype;
 325         char buf[MAXHOSTNAMELEN + 100];
 326
 327         dp = (struct icmp *)bp;
 328         ip = (struct ip *)bp2;
 329         str = buf;
 330
 331         TCHECK(dp->icmp_code);
 332         switch (dp->icmp_type) {
 333
 334         case ICMP_ECHO:
 335         case ICMP_ECHOREPLY:
 336                 TCHECK(dp->icmp_seq);
 337                 (void)snprintf(buf, sizeof(buf), "echo %s, id %u, seq %u",
 338                                dp->icmp_type == ICMP_ECHO ?
 339                                "request" : "reply",
 340                                EXTRACT_16BITS(&dp->icmp_id),
 341                                EXTRACT_16BITS(&dp->icmp_seq));
 342                 break;
 343
 344         case ICMP_UNREACH:
 345                 TCHECK(dp->icmp_ip.ip_dst);
 346                 switch (dp->icmp_code) {
 347
 348                 case ICMP_UNREACH_PROTOCOL:
 349                         TCHECK(dp->icmp_ip.ip_p);
 350                         (void)snprintf(buf, sizeof(buf),
 351                             "%s protocol %d unreachable",
 352                             ipaddr_string(&dp->icmp_ip.ip_dst),
 353                             dp->icmp_ip.ip_p);
 354                         break;
 355
 356                 case ICMP_UNREACH_PORT:
 357                         TCHECK(dp->icmp_ip.ip_p);
 358                         oip = &dp->icmp_ip;
 359                         hlen = IP_HL(oip) * 4;
 360                         ouh = (struct udphdr *)(((u_char *)oip) + hlen);
 361                         TCHECK(ouh->uh_dport);
 362                         dport = EXTRACT_16BITS(&ouh->uh_dport);
 363                         switch (oip->ip_p) {
 364
 365                         case IPPROTO_TCP:
 366                                 (void)snprintf(buf, sizeof(buf),
 367                                         "%s tcp port %s unreachable",
 368                                         ipaddr_string(&oip->ip_dst),
 369                                         tcpport_string(dport));
 370                                 break;
 371
 372                         case IPPROTO_UDP:
 373                                 (void)snprintf(buf, sizeof(buf),
 374                                         "%s udp port %s unreachable",
 375                                         ipaddr_string(&oip->ip_dst),
 376                                         udpport_string(dport));
 377                                 break;
 378
 379                         default:
 380                                 (void)snprintf(buf, sizeof(buf),
 381                                         "%s protocol %d port %d unreachable",
 382                                         ipaddr_string(&oip->ip_dst),
 383                                         oip->ip_p, dport);
 384                                 break;
 385                         }
 386                         break;
 387
 388                 case ICMP_UNREACH_NEEDFRAG:
 389                     {
 390                         register const struct mtu_discovery *mp;
 391                         mp = (struct mtu_discovery *)&dp->icmp_void;
 392                         mtu = EXTRACT_16BITS(&mp->nexthopmtu);
 393                         if (mtu) {
 394                                 (void)snprintf(buf, sizeof(buf),
 395                                     "%s unreachable - need to frag (mtu %d)",
 396                                     ipaddr_string(&dp->icmp_ip.ip_dst), mtu);
 397                         } else {
 398                                 (void)snprintf(buf, sizeof(buf),
 399                                     "%s unreachable - need to frag",
 400                                     ipaddr_string(&dp->icmp_ip.ip_dst));
 401                         }
 402                     }
 403                         break;
 404
 405                 default:
 406                         fmt = tok2str(unreach2str, "#%d %%s unreachable",
 407                             dp->icmp_code);
 408                         (void)snprintf(buf, sizeof(buf), fmt,
 409                             ipaddr_string(&dp->icmp_ip.ip_dst));
 410                         break;
 411                 }
 412                 break;
 413
 414         case ICMP_REDIRECT:
 415                 TCHECK(dp->icmp_ip.ip_dst);
 416                 fmt = tok2str(type2str, "redirect-#%d %%s to net %%s",
 417                     dp->icmp_code);
 418                 (void)snprintf(buf, sizeof(buf), fmt,
 419                     ipaddr_string(&dp->icmp_ip.ip_dst),
 420                     ipaddr_string(&dp->icmp_gwaddr));
 421                 break;
 422
 423         case ICMP_ROUTERADVERT:
 424             {
 425                 register const struct ih_rdiscovery *ihp;
 426                 register const struct id_rdiscovery *idp;
 427                 u_int lifetime, num, size;
 428
 429                 (void)snprintf(buf, sizeof(buf), "router advertisement");
 430                 cp = buf + strlen(buf);
 431
 432                 ihp = (struct ih_rdiscovery *)&dp->icmp_void;
 433                 TCHECK(*ihp);
 434                 (void)strncpy(cp, " lifetime ", sizeof(buf) - (cp - buf));
 435                 cp = buf + strlen(buf);
 436                 lifetime = EXTRACT_16BITS(&ihp->ird_lifetime);
 437                 if (lifetime < 60) {
 438                         (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u",
 439                             lifetime);
 440                 } else if (lifetime < 60 * 60) {
 441                         (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u:%02u",
 442                             lifetime / 60, lifetime % 60);
 443                 } else {
 444                         (void)snprintf(cp, sizeof(buf) - (cp - buf),
 445                             "%u:%02u:%02u",
 446                             lifetime / 3600,
 447                             (lifetime % 3600) / 60,
 448                             lifetime % 60);
 449                 }
 450                 cp = buf + strlen(buf);
 451
 452                 num = ihp->ird_addrnum;
 453                 (void)snprintf(cp, sizeof(buf) - (cp - buf), " %d:", num);
 454                 cp = buf + strlen(buf);
 455
 456                 size = ihp->ird_addrsiz;
 457                 if (size != 2) {
 458                         (void)snprintf(cp, sizeof(buf) - (cp - buf),
 459                             " [size %d]", size);
 460                         break;
 461                 }
 462                 idp = (struct id_rdiscovery *)&dp->icmp_data;
 463                 while (num-- > 0) {
 464                         TCHECK(*idp);
 465                         (void)snprintf(cp, sizeof(buf) - (cp - buf), " {%s %u}",
 466                             ipaddr_string(&idp->ird_addr),
 467                             EXTRACT_32BITS(&idp->ird_pref));
 468                         cp = buf + strlen(buf);
 469                         ++idp;
 470                 }
 471             }
 472                 break;
 473
 474         case ICMP_TIMXCEED:
 475                 TCHECK(dp->icmp_ip.ip_dst);
 476                 switch (dp->icmp_code) {
 477
 478                 case ICMP_TIMXCEED_INTRANS:
 479                         str = "time exceeded in-transit";
 480                         break;
 481
 482                 case ICMP_TIMXCEED_REASS:
 483                         str = "ip reassembly time exceeded";
 484                         break;
 485
 486                 default:
 487                         (void)snprintf(buf, sizeof(buf), "time exceeded-#%d",
 488                             dp->icmp_code);
 489                         break;
 490                 }
 491                 break;
 492
 493         case ICMP_PARAMPROB:
 494                 if (dp->icmp_code)
 495                         (void)snprintf(buf, sizeof(buf),
 496                             "parameter problem - code %d", dp->icmp_code);
 497                 else {
 498                         TCHECK(dp->icmp_pptr);
 499                         (void)snprintf(buf, sizeof(buf),
 500                             "parameter problem - octet %d", dp->icmp_pptr);
 501                 }
 502                 break;
 503
 504         case ICMP_MASKREPLY:
 505                 TCHECK(dp->icmp_mask);
 506                 (void)snprintf(buf, sizeof(buf), "address mask is 0x%08x",
 507                     EXTRACT_32BITS(&dp->icmp_mask));
 508                 break;
 509
 510         case ICMP_TSTAMP:
 511                 TCHECK(dp->icmp_seq);
 512                 (void)snprintf(buf, sizeof(buf),
 513                     "time stamp query id %u seq %u",
 514                     EXTRACT_16BITS(&dp->icmp_id),
 515                     EXTRACT_16BITS(&dp->icmp_seq));
 516                 break;
 517
 518         case ICMP_TSTAMPREPLY:
 519                 TCHECK(dp->icmp_ttime);
 520                 (void)snprintf(buf, sizeof(buf),
 521                     "time stamp reply id %u seq %u: org %s",
 522                                EXTRACT_16BITS(&dp->icmp_id),
 523                                EXTRACT_16BITS(&dp->icmp_seq),
 524                                icmp_tstamp_print(EXTRACT_32BITS(&dp->icmp_otime)));
 525
 526                 (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", recv %s",
 527                          icmp_tstamp_print(EXTRACT_32BITS(&dp->icmp_rtime)));
 528                 (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", xmit %s",
 529                          icmp_tstamp_print(EXTRACT_32BITS(&dp->icmp_ttime)));
 530                 break;
 531
 532         default:
 533                 str = tok2str(icmp2str, "type-#%d", dp->icmp_type);
 534                 break;
 535         }
 536         (void)printf("ICMP %s, length %u", str, plen);
 537         if (vflag && !fragmented) { /* don't attempt checksumming if this is a frag */
 538                 u_int16_t sum, icmp_sum;
 539                 if (TTEST2(*bp, plen)) {
 540                         sum = in_cksum((u_short*)dp, plen, 0);
 541                         if (sum != 0) {
 542                                 icmp_sum = EXTRACT_16BITS(&dp->icmp_cksum);
 543                                 (void)printf(" (wrong icmp cksum %x (->%x)!)",
 544                                              icmp_sum,
 545                                              in_cksum_shouldbe(icmp_sum, sum));
 546                         }
 547                 }
 548         }
 549         if (vflag >= 1 && !ICMP_INFOTYPE(dp->icmp_type)) {
 550                 bp += 8;
 551                 (void)printf("\n\t");
 552                 ip = (struct ip *)bp;
 553                 snaplen = snapend - bp;
 554                 ip_print(gndo, bp, EXTRACT_16BITS(&ip->ip_len));
 555         }
 556
 557         if (vflag >= 1 && plen > ICMP_EXTD_MINLEN && ICMP_MPLS_EXT_TYPE(dp->icmp_type)) {
 558
 559             TCHECK(*(dp->icmp_mpls_ext_version));
 560             printf("\n\tMPLS extension v%u",ICMP_MPLS_EXT_EXTRACT_VERSION(*(dp->icmp_mpls_ext_version)));
 561
 562             /*
 563              * Sanity checking of the header.
 564              */
 565             if (ICMP_MPLS_EXT_EXTRACT_VERSION(*(dp->icmp_mpls_ext_version)) != ICMP_MPLS_EXT_VERSION) {
 566                 printf(" packet not supported");
 567                 return;
 568             }
 569
 570             hlen = plen - ICMP_EXTD_MINLEN;
 571             TCHECK2(*(dp->icmp_mpls_ext_checksum), 2);
 572             printf(", checksum 0x%04x (unverified), length %u", /* FIXME */
 573                    EXTRACT_16BITS(dp->icmp_mpls_ext_checksum),
 574                    hlen);
 575
 576             hlen -= 4; /* subtract common header size */
 577             obj_tptr = (u_int8_t *)dp->icmp_mpls_ext_data;
 578
 579             while (hlen > sizeof(struct icmp_mpls_ext_object_header_t)) {
 580
 581                 icmp_mpls_ext_object_header = (struct icmp_mpls_ext_object_header_t *)obj_tptr;
 582                 TCHECK(*icmp_mpls_ext_object_header);
 583                 obj_tlen = EXTRACT_16BITS(icmp_mpls_ext_object_header->length);
 584                 obj_class_num = icmp_mpls_ext_object_header->class_num;
 585                 obj_ctype = icmp_mpls_ext_object_header->ctype;
 586                 obj_tptr += sizeof(struct icmp_mpls_ext_object_header_t);
 587
 588                 printf("\n\t  %s Object (%u), Class-Type: %u, length %u",
 589                        tok2str(icmp_mpls_ext_obj_values,"unknown",obj_class_num),
 590                        obj_class_num,
 591                        obj_ctype,
 592                        obj_tlen);
 593
 594                 hlen-=sizeof(struct icmp_mpls_ext_object_header_t); /* length field includes tlv header */
 595                 if (obj_tlen < sizeof(struct icmp_mpls_ext_object_header_t))
 596                     break;
 597                 obj_tlen-=sizeof(struct icmp_mpls_ext_object_header_t);
 598
 599                 switch (obj_class_num) {
 600                 case 1:
 601                     switch(obj_ctype) {
 602                     case 1:
 603                         TCHECK2(*obj_tptr, 4);
 604                         raw_label = EXTRACT_32BITS(obj_tptr);
 605                         printf("\n\t    label %u, exp %u", MPLS_LABEL(raw_label), MPLS_EXP(raw_label));
 606                         if (MPLS_STACK(raw_label))
 607                             printf(", [S]");
 608                         printf(", ttl %u", MPLS_TTL(raw_label));
 609                         break;
 610                     default:
 611                         print_unknown_data(obj_tptr, "\n\t    ", obj_tlen);
 612                     }
 613                     break;
 614
 615                /*
 616                 *  FIXME those are the defined objects that lack a decoder
 617                 *  you are welcome to contribute code ;-)
 618                 */
 619                 case 2:
 620                 default:
 621                     print_unknown_data(obj_tptr, "\n\t    ", obj_tlen);
 622                     break;
 623                 }
 624                 if (hlen < obj_tlen)
 625                     break;
 626                 hlen -= obj_tlen;
 627                 obj_tptr += obj_tlen;
 628             }
 629         }
 630
 631         return;
 632 trunc:
 633         fputs("[|icmp]", stdout);
 634 }