contrib/tcpdump-3.8.3/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
  22 #ifndef lint
  23 static const char rcsid[] _U_ =
  24     "@(#) $Header: /tcpdump/master/tcpdump/print-icmp.c,v 1.73.2.3 2004/03/24 00:56:34 guy Exp $ (LBL)";
  25 #endif
  26
  27 #ifdef HAVE_CONFIG_H
  28 #include "config.h"
  29 #endif
  30
  31 #include <tcpdump-stdinc.h>
  32
  33 #include <stdio.h>
  34 #include <string.h>
  35
  36 #include "interface.h"
  37 #include "addrtoname.h"
  38 #include "extract.h"                    /* must come after interface.h */
  39
  40 #include "ip.h"
  41 #include "udp.h"
  42 #include "ipproto.h"
  43
  44 /*
  45  * Interface Control Message Protocol Definitions.
  46  * Per RFC 792, September 1981.
  47  */
  48
  49 /*
  50  * Structure of an icmp header.
  51  */
  52 struct icmp {
  53         u_int8_t  icmp_type;            /* type of message, see below */
  54         u_int8_t  icmp_code;            /* type sub code */
  55         u_int16_t icmp_cksum;           /* ones complement cksum of struct */
  56         union {
  57                 u_int8_t ih_pptr;                       /* ICMP_PARAMPROB */
  58                 struct in_addr ih_gwaddr;       /* ICMP_REDIRECT */
  59                 struct ih_idseq {
  60                         u_int16_t icd_id;
  61                         u_int16_t icd_seq;
  62                 } ih_idseq;
  63                 u_int32_t ih_void;
  64
  65                 /* ICMP_UNREACH_NEEDFRAG -- Path MTU Discovery (RFC1191) */
  66                 struct ih_pmtu {
  67                         u_int16_t ipm_void;
  68                         u_int16_t ipm_nextmtu;
  69                 } ih_pmtu;
  70         } icmp_hun;
  71 #define icmp_pptr       icmp_hun.ih_pptr
  72 #define icmp_gwaddr     icmp_hun.ih_gwaddr
  73 #define icmp_id         icmp_hun.ih_idseq.icd_id
  74 #define icmp_seq        icmp_hun.ih_idseq.icd_seq
  75 #define icmp_void       icmp_hun.ih_void
  76 #define icmp_pmvoid     icmp_hun.ih_pmtu.ipm_void
  77 #define icmp_nextmtu    icmp_hun.ih_pmtu.ipm_nextmtu
  78         union {
  79                 struct id_ts {
  80                         u_int32_t its_otime;
  81                         u_int32_t its_rtime;
  82                         u_int32_t its_ttime;
  83                 } id_ts;
  84                 struct id_ip  {
  85                         struct ip idi_ip;
  86                         /* options and then 64 bits of data */
  87                 } id_ip;
  88                 u_int32_t id_mask;
  89                 u_int8_t id_data[1];
  90         } icmp_dun;
  91 #define icmp_otime      icmp_dun.id_ts.its_otime
  92 #define icmp_rtime      icmp_dun.id_ts.its_rtime
  93 #define icmp_ttime      icmp_dun.id_ts.its_ttime
  94 #define icmp_ip         icmp_dun.id_ip.idi_ip
  95 #define icmp_mask       icmp_dun.id_mask
  96 #define icmp_data       icmp_dun.id_data
  97 };
  98
  99 /*
 100  * Lower bounds on packet lengths for various types.
 101  * For the error advice packets must first insure that the
 102  * packet is large enought to contain the returned ip header.
 103  * Only then can we do the check to see if 64 bits of packet
 104  * data have been returned, since we need to check the returned
 105  * ip header length.
 106  */
 107 #define ICMP_MINLEN     8                               /* abs minimum */
 108 #define ICMP_TSLEN      (8 + 3 * sizeof (u_int32_t))    /* timestamp */
 109 #define ICMP_MASKLEN    12                              /* address mask */
 110 #define ICMP_ADVLENMIN  (8 + sizeof (struct ip) + 8)    /* min */
 111 #define ICMP_ADVLEN(p)  (8 + (IP_HL(&(p)->icmp_ip) << 2) + 8)
 112         /* N.B.: must separately check that ip_hl >= 5 */
 113
 114 /*
 115  * Definition of type and code field values.
 116  */
 117 #define ICMP_ECHOREPLY          0               /* echo reply */
 118 #define ICMP_UNREACH            3               /* dest unreachable, codes: */
 119 #define         ICMP_UNREACH_NET        0               /* bad net */
 120 #define         ICMP_UNREACH_HOST       1               /* bad host */
 121 #define         ICMP_UNREACH_PROTOCOL   2               /* bad protocol */
 122 #define         ICMP_UNREACH_PORT       3               /* bad port */
 123 #define         ICMP_UNREACH_NEEDFRAG   4               /* IP_DF caused drop */
 124 #define         ICMP_UNREACH_SRCFAIL    5               /* src route failed */
 125 #define         ICMP_UNREACH_NET_UNKNOWN 6              /* unknown net */
 126 #define         ICMP_UNREACH_HOST_UNKNOWN 7             /* unknown host */
 127 #define         ICMP_UNREACH_ISOLATED   8               /* src host isolated */
 128 #define         ICMP_UNREACH_NET_PROHIB 9               /* prohibited access */
 129 #define         ICMP_UNREACH_HOST_PROHIB 10             /* ditto */
 130 #define         ICMP_UNREACH_TOSNET     11              /* bad tos for net */
 131 #define         ICMP_UNREACH_TOSHOST    12              /* bad tos for host */
 132 #define ICMP_SOURCEQUENCH       4               /* packet lost, slow down */
 133 #define ICMP_REDIRECT           5               /* shorter route, codes: */
 134 #define         ICMP_REDIRECT_NET       0               /* for network */
 135 #define         ICMP_REDIRECT_HOST      1               /* for host */
 136 #define         ICMP_REDIRECT_TOSNET    2               /* for tos and net */
 137 #define         ICMP_REDIRECT_TOSHOST   3               /* for tos and host */
 138 #define ICMP_ECHO               8               /* echo service */
 139 #define ICMP_ROUTERADVERT       9               /* router advertisement */
 140 #define ICMP_ROUTERSOLICIT      10              /* router solicitation */
 141 #define ICMP_TIMXCEED           11              /* time exceeded, code: */
 142 #define         ICMP_TIMXCEED_INTRANS   0               /* ttl==0 in transit */
 143 #define         ICMP_TIMXCEED_REASS     1               /* ttl==0 in reass */
 144 #define ICMP_PARAMPROB          12              /* ip header bad */
 145 #define         ICMP_PARAMPROB_OPTABSENT 1              /* req. opt. absent */
 146 #define ICMP_TSTAMP             13              /* timestamp request */
 147 #define ICMP_TSTAMPREPLY        14              /* timestamp reply */
 148 #define ICMP_IREQ               15              /* information request */
 149 #define ICMP_IREQREPLY          16              /* information reply */
 150 #define ICMP_MASKREQ            17              /* address mask request */
 151 #define ICMP_MASKREPLY          18              /* address mask reply */
 152
 153 #define ICMP_MAXTYPE            18
 154
 155 #define ICMP_INFOTYPE(type) \
 156         ((type) == ICMP_ECHOREPLY || (type) == ICMP_ECHO || \
 157         (type) == ICMP_ROUTERADVERT || (type) == ICMP_ROUTERSOLICIT || \
 158         (type) == ICMP_TSTAMP || (type) == ICMP_TSTAMPREPLY || \
 159         (type) == ICMP_IREQ || (type) == ICMP_IREQREPLY || \
 160         (type) == ICMP_MASKREQ || (type) == ICMP_MASKREPLY)
 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 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 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 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         u_int16_t unused;
 248         u_int16_t nexthopmtu;
 249 };
 250
 251 /* rfc1256 */
 252 struct ih_rdiscovery {
 253         u_int8_t ird_addrnum;
 254         u_int8_t ird_addrsiz;
 255         u_int16_t ird_lifetime;
 256 };
 257
 258 struct id_rdiscovery {
 259         u_int32_t ird_addr;
 260         u_int32_t ird_pref;
 261 };
 262
 263 void
 264 icmp_print(const u_char *bp, u_int plen, const u_char *bp2, int fragmented)
 265 {
 266         char *cp;
 267         const struct icmp *dp;
 268         const struct ip *ip;
 269         const char *str, *fmt;
 270         const struct ip *oip;
 271         const struct udphdr *ouh;
 272         u_int hlen, dport, mtu;
 273         char buf[MAXHOSTNAMELEN + 100];
 274
 275         dp = (struct icmp *)bp;
 276         ip = (struct ip *)bp2;
 277         str = buf;
 278
 279         TCHECK(dp->icmp_code);
 280         switch (dp->icmp_type) {
 281
 282         case ICMP_ECHO:
 283         case ICMP_ECHOREPLY:
 284                 TCHECK(dp->icmp_seq);
 285                 (void)snprintf(buf, sizeof(buf), "echo %s seq %u",
 286                         dp->icmp_type == ICMP_ECHO ?
 287                         "request" : "reply",
 288                         EXTRACT_16BITS(&dp->icmp_seq));
 289                 break;
 290
 291         case ICMP_UNREACH:
 292                 TCHECK(dp->icmp_ip.ip_dst);
 293                 switch (dp->icmp_code) {
 294
 295                 case ICMP_UNREACH_PROTOCOL:
 296                         TCHECK(dp->icmp_ip.ip_p);
 297                         (void)snprintf(buf, sizeof(buf),
 298                             "%s protocol %d unreachable",
 299                             ipaddr_string(&dp->icmp_ip.ip_dst),
 300                             dp->icmp_ip.ip_p);
 301                         break;
 302
 303                 case ICMP_UNREACH_PORT:
 304                         TCHECK(dp->icmp_ip.ip_p);
 305                         oip = &dp->icmp_ip;
 306                         hlen = IP_HL(oip) * 4;
 307                         ouh = (struct udphdr *)(((u_char *)oip) + hlen);
 308                         TCHECK(ouh->uh_dport);
 309                         dport = EXTRACT_16BITS(&ouh->uh_dport);
 310                         switch (oip->ip_p) {
 311
 312                         case IPPROTO_TCP:
 313                                 (void)snprintf(buf, sizeof(buf),
 314                                         "%s tcp port %s unreachable",
 315                                         ipaddr_string(&oip->ip_dst),
 316                                         tcpport_string(dport));
 317                                 break;
 318
 319                         case IPPROTO_UDP:
 320                                 (void)snprintf(buf, sizeof(buf),
 321                                         "%s udp port %s unreachable",
 322                                         ipaddr_string(&oip->ip_dst),
 323                                         udpport_string(dport));
 324                                 break;
 325
 326                         default:
 327                                 (void)snprintf(buf, sizeof(buf),
 328                                         "%s protocol %d port %d unreachable",
 329                                         ipaddr_string(&oip->ip_dst),
 330                                         oip->ip_p, dport);
 331                                 break;
 332                         }
 333                         break;
 334
 335                 case ICMP_UNREACH_NEEDFRAG:
 336                     {
 337                         register const struct mtu_discovery *mp;
 338                         mp = (struct mtu_discovery *)&dp->icmp_void;
 339                         mtu = EXTRACT_16BITS(&mp->nexthopmtu);
 340                         if (mtu) {
 341                                 (void)snprintf(buf, sizeof(buf),
 342                                     "%s unreachable - need to frag (mtu %d)",
 343                                     ipaddr_string(&dp->icmp_ip.ip_dst), mtu);
 344                         } else {
 345                                 (void)snprintf(buf, sizeof(buf),
 346                                     "%s unreachable - need to frag",
 347                                     ipaddr_string(&dp->icmp_ip.ip_dst));
 348                         }
 349                     }
 350                         break;
 351
 352                 default:
 353                         fmt = tok2str(unreach2str, "#%d %%s unreachable",
 354                             dp->icmp_code);
 355                         (void)snprintf(buf, sizeof(buf), fmt,
 356                             ipaddr_string(&dp->icmp_ip.ip_dst));
 357                         break;
 358                 }
 359                 break;
 360
 361         case ICMP_REDIRECT:
 362                 TCHECK(dp->icmp_ip.ip_dst);
 363                 fmt = tok2str(type2str, "redirect-#%d %%s to net %%s",
 364                     dp->icmp_code);
 365                 (void)snprintf(buf, sizeof(buf), fmt,
 366                     ipaddr_string(&dp->icmp_ip.ip_dst),
 367                     ipaddr_string(&dp->icmp_gwaddr));
 368                 break;
 369
 370         case ICMP_ROUTERADVERT:
 371             {
 372                 register const struct ih_rdiscovery *ihp;
 373                 register const struct id_rdiscovery *idp;
 374                 u_int lifetime, num, size;
 375
 376                 (void)snprintf(buf, sizeof(buf), "router advertisement");
 377                 cp = buf + strlen(buf);
 378
 379                 ihp = (struct ih_rdiscovery *)&dp->icmp_void;
 380                 TCHECK(*ihp);
 381                 (void)strncpy(cp, " lifetime ", sizeof(buf) - (cp - buf));
 382                 cp = buf + strlen(buf);
 383                 lifetime = EXTRACT_16BITS(&ihp->ird_lifetime);
 384                 if (lifetime < 60) {
 385                         (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u",
 386                             lifetime);
 387                 } else if (lifetime < 60 * 60) {
 388                         (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u:%02u",
 389                             lifetime / 60, lifetime % 60);
 390                 } else {
 391                         (void)snprintf(cp, sizeof(buf) - (cp - buf),
 392                             "%u:%02u:%02u",
 393                             lifetime / 3600,
 394                             (lifetime % 3600) / 60,
 395                             lifetime % 60);
 396                 }
 397                 cp = buf + strlen(buf);
 398
 399                 num = ihp->ird_addrnum;
 400                 (void)snprintf(cp, sizeof(buf) - (cp - buf), " %d:", num);
 401                 cp = buf + strlen(buf);
 402
 403                 size = ihp->ird_addrsiz;
 404                 if (size != 2) {
 405                         (void)snprintf(cp, sizeof(buf) - (cp - buf),
 406                             " [size %d]", size);
 407                         break;
 408                 }
 409                 idp = (struct id_rdiscovery *)&dp->icmp_data;
 410                 while (num-- > 0) {
 411                         TCHECK(*idp);
 412                         (void)snprintf(cp, sizeof(buf) - (cp - buf), " {%s %u}",
 413                             ipaddr_string(&idp->ird_addr),
 414                             EXTRACT_32BITS(&idp->ird_pref));
 415                         cp = buf + strlen(buf);
 416                         ++idp;
 417                 }
 418             }
 419                 break;
 420
 421         case ICMP_TIMXCEED:
 422                 TCHECK(dp->icmp_ip.ip_dst);
 423                 switch (dp->icmp_code) {
 424
 425                 case ICMP_TIMXCEED_INTRANS:
 426                         str = "time exceeded in-transit";
 427                         break;
 428
 429                 case ICMP_TIMXCEED_REASS:
 430                         str = "ip reassembly time exceeded";
 431                         break;
 432
 433                 default:
 434                         (void)snprintf(buf, sizeof(buf), "time exceeded-#%d",
 435                             dp->icmp_code);
 436                         break;
 437                 }
 438                 break;
 439
 440         case ICMP_PARAMPROB:
 441                 if (dp->icmp_code)
 442                         (void)snprintf(buf, sizeof(buf),
 443                             "parameter problem - code %d", dp->icmp_code);
 444                 else {
 445                         TCHECK(dp->icmp_pptr);
 446                         (void)snprintf(buf, sizeof(buf),
 447                             "parameter problem - octet %d", dp->icmp_pptr);
 448                 }
 449                 break;
 450
 451         case ICMP_MASKREPLY:
 452                 TCHECK(dp->icmp_mask);
 453                 (void)snprintf(buf, sizeof(buf), "address mask is 0x%08x",
 454                     EXTRACT_32BITS(&dp->icmp_mask));
 455                 break;
 456
 457         case ICMP_TSTAMP:
 458                 TCHECK(dp->icmp_seq);
 459                 (void)snprintf(buf, sizeof(buf),
 460                     "time stamp query id %u seq %u",
 461                     EXTRACT_16BITS(&dp->icmp_id),
 462                     EXTRACT_16BITS(&dp->icmp_seq));
 463                 break;
 464
 465         case ICMP_TSTAMPREPLY:
 466                 TCHECK(dp->icmp_ttime);
 467                 (void)snprintf(buf, sizeof(buf),
 468                     "time stamp reply id %u seq %u : org 0x%x recv 0x%x xmit 0x%x",
 469                     EXTRACT_16BITS(&dp->icmp_id),
 470                     EXTRACT_16BITS(&dp->icmp_seq),
 471                     EXTRACT_32BITS(&dp->icmp_otime),
 472                     EXTRACT_32BITS(&dp->icmp_rtime),
 473                     EXTRACT_32BITS(&dp->icmp_ttime));
 474                 break;
 475
 476         default:
 477                 str = tok2str(icmp2str, "type-#%d", dp->icmp_type);
 478                 break;
 479         }
 480         (void)printf("icmp %d: %s", plen, str);
 481         if (vflag && !fragmented) { /* don't attempt checksumming if this is a frag */
 482                 u_int16_t sum, icmp_sum;
 483                 if (TTEST2(*bp, plen)) {
 484                         sum = in_cksum((u_short*)dp, plen, 0);
 485                         if (sum != 0) {
 486                                 icmp_sum = EXTRACT_16BITS(&dp->icmp_cksum);
 487                                 (void)printf(" (wrong icmp cksum %x (->%x)!)",
 488                                              icmp_sum,
 489                                              in_cksum_shouldbe(icmp_sum, sum));
 490                         }
 491                 }
 492         }
 493         if (vflag > 1 && !ICMP_INFOTYPE(dp->icmp_type)) {
 494                 bp += 8;
 495                 (void)printf(" for ");
 496                 ip = (struct ip *)bp;
 497                 snaplen = snapend - bp;
 498                 ip_print(bp, EXTRACT_16BITS(&ip->ip_len));
 499         }
 500         return;
 501 trunc:
 502         fputs("[|icmp]", stdout);
 503 }