The Tcpdump Group git mirrors - tcpdump/blob - print-ether.c

   1 /*
   2  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000
   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: Ethernet printer */
  23
  24 #ifdef HAVE_CONFIG_H
  25 #include <config.h>
  26 #endif
  27
  28 #include "netdissect-stdinc.h"
  29
  30 #include "netdissect.h"
  31 #include "extract.h"
  32 #include "addrtoname.h"
  33 #include "ethertype.h"
  34
  35 /*
  36  * Structure of an Ethernet header.
  37  */
  38 struct  ether_header {
  39         nd_mac_addr     ether_dhost;
  40         nd_mac_addr     ether_shost;
  41         nd_uint16_t     ether_length_type;
  42 };
  43
  44 /*
  45  * Length of an Ethernet header; note that some compilers may pad
  46  * "struct ether_header" to a multiple of 4 bytes, for example, so
  47  * "sizeof (struct ether_header)" may not give the right answer.
  48  */
  49 #define ETHER_HDRLEN            14
  50
  51 const struct tok ethertype_values[] = {
  52     { ETHERTYPE_IP,             "IPv4" },
  53     { ETHERTYPE_MPLS,           "MPLS unicast" },
  54     { ETHERTYPE_MPLS_MULTI,     "MPLS multicast" },
  55     { ETHERTYPE_IPV6,           "IPv6" },
  56     { ETHERTYPE_8021Q,          "802.1Q" },
  57     { ETHERTYPE_8021Q9100,      "802.1Q-9100" },
  58     { ETHERTYPE_8021QinQ,       "802.1Q-QinQ" },
  59     { ETHERTYPE_8021Q9200,      "802.1Q-9200" },
  60     { ETHERTYPE_VMAN,           "VMAN" },
  61     { ETHERTYPE_PUP,            "PUP" },
  62     { ETHERTYPE_ARP,            "ARP"},
  63     { ETHERTYPE_REVARP,         "Reverse ARP"},
  64     { ETHERTYPE_NS,             "NS" },
  65     { ETHERTYPE_SPRITE,         "Sprite" },
  66     { ETHERTYPE_TRAIL,          "Trail" },
  67     { ETHERTYPE_MOPDL,          "MOP DL" },
  68     { ETHERTYPE_MOPRC,          "MOP RC" },
  69     { ETHERTYPE_DN,             "DN" },
  70     { ETHERTYPE_LAT,            "LAT" },
  71     { ETHERTYPE_SCA,            "SCA" },
  72     { ETHERTYPE_TEB,            "TEB" },
  73     { ETHERTYPE_LANBRIDGE,      "Lanbridge" },
  74     { ETHERTYPE_DECDNS,         "DEC DNS" },
  75     { ETHERTYPE_DECDTS,         "DEC DTS" },
  76     { ETHERTYPE_VEXP,           "VEXP" },
  77     { ETHERTYPE_VPROD,          "VPROD" },
  78     { ETHERTYPE_ATALK,          "Appletalk" },
  79     { ETHERTYPE_AARP,           "Appletalk ARP" },
  80     { ETHERTYPE_IPX,            "IPX" },
  81     { ETHERTYPE_PPP,            "PPP" },
  82     { ETHERTYPE_MPCP,           "MPCP" },
  83     { ETHERTYPE_SLOW,           "Slow Protocols" },
  84     { ETHERTYPE_PPPOED,         "PPPoE D" },
  85     { ETHERTYPE_PPPOES,         "PPPoE S" },
  86     { ETHERTYPE_EAPOL,          "EAPOL" },
  87     { ETHERTYPE_RRCP,           "RRCP" },
  88     { ETHERTYPE_MS_NLB_HB,      "MS NLB heartbeat" },
  89     { ETHERTYPE_JUMBO,          "Jumbo" },
  90     { ETHERTYPE_NSH,            "NSH" },
  91     { ETHERTYPE_LOOPBACK,       "Loopback" },
  92     { ETHERTYPE_ISO,            "OSI" },
  93     { ETHERTYPE_GRE_ISO,        "GRE-OSI" },
  94     { ETHERTYPE_CFM_OLD,        "CFM (old)" },
  95     { ETHERTYPE_CFM,            "CFM" },
  96     { ETHERTYPE_IEEE1905_1,     "IEEE1905.1" },
  97     { ETHERTYPE_LLDP,           "LLDP" },
  98     { ETHERTYPE_TIPC,           "TIPC"},
  99     { ETHERTYPE_GEONET_OLD,     "GeoNet (old)"},
 100     { ETHERTYPE_GEONET,         "GeoNet"},
 101     { ETHERTYPE_CALM_FAST,      "CALM FAST"},
 102     { ETHERTYPE_AOE,            "AoE" },
 103     { 0, NULL}
 104 };
 105
 106 static void
 107 ether_hdr_print(netdissect_options *ndo,
 108                 const u_char *bp, u_int length,
 109                 u_int hdrlen)
 110 {
 111         const struct ether_header *ehp;
 112         uint16_t length_type;
 113
 114         ehp = (const struct ether_header *)bp;
 115
 116         ND_PRINT("%s > %s",
 117                  etheraddr_string(ndo, ehp->ether_shost),
 118                  etheraddr_string(ndo, ehp->ether_dhost));
 119
 120         length_type = GET_BE_U_2(bp + (hdrlen - sizeof(ehp->ether_length_type)));
 121         if (!ndo->ndo_qflag) {
 122                 if (length_type <= MAX_ETHERNET_LENGTH_VAL) {
 123                         ND_PRINT(", 802.3");
 124                         length = length_type;
 125                 } else
 126                         ND_PRINT(", ethertype %s (0x%04x)",
 127                                  tok2str(ethertype_values,"Unknown", length_type),
 128                                  length_type);
 129         } else {
 130                 if (length_type <= MAX_ETHERNET_LENGTH_VAL) {
 131                         ND_PRINT(", 802.3");
 132                         length = length_type;
 133                 } else
 134                         ND_PRINT(", %s", tok2str(ethertype_values,"Unknown Ethertype (0x%04x)", length_type));
 135         }
 136
 137         ND_PRINT(", length %u: ", length);
 138 }
 139
 140 /*
 141  * Print an Ethernet frame while specyfing a non-standard Ethernet header
 142  * length.
 143  * This might be encapsulated within another frame; we might be passed
 144  * a pointer to a function that can print header information for that
 145  * frame's protocol, and an argument to pass to that function.
 146  *
 147  * FIXME: caplen can and should be derived from ndo->ndo_snapend and p.
 148  */
 149 u_int
 150 ether_hdr_len_print(netdissect_options *ndo,
 151                     const u_char *p, u_int length, u_int caplen,
 152                     void (*print_encap_header)(netdissect_options *ndo, const u_char *),
 153                     const u_char *encap_header_arg, u_int hdrlen)
 154 {
 155         const struct ether_header *ehp;
 156         u_int orig_length;
 157         u_short length_type;
 158         int llc_hdrlen;
 159         struct lladdr_info src, dst;
 160
 161         /* Unless specified otherwise, assume a standard Ethernet header */
 162         if (hdrlen == ETHER_HDRLEN)
 163                 ndo->ndo_protocol = "ether";
 164
 165         if (caplen < hdrlen) {
 166                 nd_print_trunc(ndo);
 167                 return (caplen);
 168         }
 169         if (length < hdrlen) {
 170                 nd_print_trunc(ndo);
 171                 return (length);
 172         }
 173
 174         /* If the offset is set, then the upper printer is responsible for
 175          * printing the relevant part of the Ethernet header.
 176          */
 177         if (ndo->ndo_eflag) {
 178                 if (print_encap_header != NULL)
 179                         (*print_encap_header)(ndo, encap_header_arg);
 180                 ether_hdr_print(ndo, p, length, hdrlen);
 181         }
 182
 183         orig_length = length;
 184
 185         length -= hdrlen;
 186         caplen -= hdrlen;
 187         ehp = (const struct ether_header *)p;
 188         p += hdrlen;
 189
 190         src.addr = ehp->ether_shost;
 191         src.addr_string = etheraddr_string;
 192         dst.addr = ehp->ether_dhost;
 193         dst.addr_string = etheraddr_string;
 194         length_type = GET_BE_U_2((const u_char *)ehp + (hdrlen - sizeof(ehp->ether_length_type)));
 195
 196 recurse:
 197         /*
 198          * Is it (gag) an 802.3 encapsulation?
 199          */
 200         if (length_type <= MAX_ETHERNET_LENGTH_VAL) {
 201                 /* Try to print the LLC-layer header & higher layers */
 202                 llc_hdrlen = llc_print(ndo, p, length, caplen, &src, &dst);
 203                 if (llc_hdrlen < 0) {
 204                         /* packet type not known, print raw packet */
 205                         if (!ndo->ndo_suppress_default_print)
 206                                 ND_DEFAULTPRINT(p, caplen);
 207                         llc_hdrlen = -llc_hdrlen;
 208                 }
 209                 hdrlen += llc_hdrlen;
 210         } else if (length_type == ETHERTYPE_8021Q  ||
 211                 length_type == ETHERTYPE_8021Q9100 ||
 212                 length_type == ETHERTYPE_8021Q9200 ||
 213                 length_type == ETHERTYPE_8021QinQ) {
 214                 /*
 215                  * Print VLAN information, and then go back and process
 216                  * the enclosed type field.
 217                  */
 218                 if (caplen < 4) {
 219                         ndo->ndo_protocol = "vlan";
 220                         nd_print_trunc(ndo);
 221                         return (hdrlen + caplen);
 222                 }
 223                 if (length < 4) {
 224                         ndo->ndo_protocol = "vlan";
 225                         nd_print_trunc(ndo);
 226                         return (hdrlen + length);
 227                 }
 228                 if (ndo->ndo_eflag) {
 229                         uint16_t tag = GET_BE_U_2(p);
 230
 231                         ND_PRINT("%s, ", ieee8021q_tci_string(tag));
 232                 }
 233
 234                 length_type = GET_BE_U_2(p + 2);
 235                 if (ndo->ndo_eflag && length_type > MAX_ETHERNET_LENGTH_VAL)
 236                         ND_PRINT("ethertype %s, ", tok2str(ethertype_values,"0x%04x", length_type));
 237                 p += 4;
 238                 length -= 4;
 239                 caplen -= 4;
 240                 hdrlen += 4;
 241                 goto recurse;
 242         } else if (length_type == ETHERTYPE_JUMBO) {
 243                 /*
 244                  * Alteon jumbo frames.
 245                  * See
 246                  *
 247                  *      http://tools.ietf.org/html/draft-ietf-isis-ext-eth-01
 248                  *
 249                  * which indicates that, following the type field,
 250                  * there's an LLC header and payload.
 251                  */
 252                 /* Try to print the LLC-layer header & higher layers */
 253                 llc_hdrlen = llc_print(ndo, p, length, caplen, &src, &dst);
 254                 if (llc_hdrlen < 0) {
 255                         /* packet type not known, print raw packet */
 256                         if (!ndo->ndo_suppress_default_print)
 257                                 ND_DEFAULTPRINT(p, caplen);
 258                         llc_hdrlen = -llc_hdrlen;
 259                 }
 260                 hdrlen += llc_hdrlen;
 261         } else {
 262                 if (ethertype_print(ndo, length_type, p, length, caplen, &src, &dst) == 0) {
 263                         /* type not known, print raw packet */
 264                         if (!ndo->ndo_eflag) {
 265                                 if (print_encap_header != NULL)
 266                                         (*print_encap_header)(ndo, encap_header_arg);
 267                                 ether_hdr_print(ndo, (const u_char *)ehp, orig_length,
 268                                                 hdrlen);
 269                         }
 270
 271                         if (!ndo->ndo_suppress_default_print)
 272                                 ND_DEFAULTPRINT(p, caplen);
 273                 }
 274         }
 275         return (hdrlen);
 276 }
 277
 278 /*
 279  * Print an Ethernet frame.
 280  * This might be encapsulated within another frame; we might be passed
 281  * a pointer to a function that can print header information for that
 282  * frame's protocol, and an argument to pass to that function.
 283  *
 284  * FIXME: caplen can and should be derived from ndo->ndo_snapend and p.
 285  */
 286 u_int
 287 ether_print(netdissect_options *ndo,
 288             const u_char *p, u_int length, u_int caplen,
 289             void (*print_encap_header)(netdissect_options *ndo, const u_char *),
 290             const u_char *encap_header_arg)
 291 {
 292         return (ether_hdr_len_print(ndo, p, length, caplen,
 293                                     print_encap_header, encap_header_arg,
 294                                     ETHER_HDRLEN));
 295 }
 296
 297 /*
 298  * This is the top level routine of the printer.  'p' points
 299  * to the ether header of the packet, 'h->len' is the length
 300  * of the packet off the wire, and 'h->caplen' is the number
 301  * of bytes actually captured.
 302  */
 303 u_int
 304 ether_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h,
 305                const u_char *p)
 306 {
 307         ndo->ndo_protocol = "ether_if";
 308         return (ether_print(ndo, p, h->len, h->caplen, NULL, NULL));
 309 }
 310
 311 /*
 312  * This is the top level routine of the printer.  'p' points
 313  * to the ether header of the packet, 'h->len' is the length
 314  * of the packet off the wire, and 'h->caplen' is the number
 315  * of bytes actually captured.
 316  *
 317  * This is for DLT_NETANALYZER, which has a 4-byte pseudo-header
 318  * before the Ethernet header.
 319  */
 320 u_int
 321 netanalyzer_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h,
 322                      const u_char *p)
 323 {
 324         /*
 325          * Fail if we don't have enough data for the Hilscher pseudo-header.
 326          */
 327         ndo->ndo_protocol = "netanalyzer_if";
 328         if (h->caplen < 4) {
 329                 nd_print_trunc(ndo);
 330                 return (h->caplen);
 331         }
 332
 333         /* Skip the pseudo-header. */
 334         return (4 + ether_print(ndo, p + 4, h->len - 4, h->caplen - 4, NULL, NULL));
 335 }
 336
 337 /*
 338  * This is the top level routine of the printer.  'p' points
 339  * to the ether header of the packet, 'h->len' is the length
 340  * of the packet off the wire, and 'h->caplen' is the number
 341  * of bytes actually captured.
 342  *
 343  * This is for DLT_NETANALYZER_TRANSPARENT, which has a 4-byte
 344  * pseudo-header, a 7-byte Ethernet preamble, and a 1-byte Ethernet SOF
 345  * before the Ethernet header.
 346  */
 347 u_int
 348 netanalyzer_transparent_if_print(netdissect_options *ndo,
 349                                  const struct pcap_pkthdr *h,
 350                                  const u_char *p)
 351 {
 352         /*
 353          * Fail if we don't have enough data for the Hilscher pseudo-header,
 354          * preamble, and SOF.
 355          */
 356         ndo->ndo_protocol = "netanalyzer_transparent_if";
 357         if (h->caplen < 12) {
 358                 nd_print_trunc(ndo);
 359                 return (h->caplen);
 360         }
 361
 362         /* Skip the pseudo-header, preamble, and SOF. */
 363         return (12 + ether_print(ndo, p + 12, h->len - 12, h->caplen - 12, NULL, NULL));
 364 }
 365
 366 /*
 367  * Prints the packet payload, given an Ethernet type code for the payload's
 368  * protocol.
 369  *
 370  * Returns non-zero if it can do so, zero if the ethertype is unknown.
 371  */
 372
 373 int
 374 ethertype_print(netdissect_options *ndo,
 375                 u_short ether_type, const u_char *p,
 376                 u_int length, u_int caplen,
 377                 const struct lladdr_info *src, const struct lladdr_info *dst)
 378 {
 379         switch (ether_type) {
 380
 381         case ETHERTYPE_IP:
 382                 ip_print(ndo, p, length);
 383                 return (1);
 384
 385         case ETHERTYPE_IPV6:
 386                 ip6_print(ndo, p, length);
 387                 return (1);
 388
 389         case ETHERTYPE_ARP:
 390         case ETHERTYPE_REVARP:
 391                 arp_print(ndo, p, length, caplen);
 392                 return (1);
 393
 394         case ETHERTYPE_DN:
 395                 decnet_print(ndo, p, length, caplen);
 396                 return (1);
 397
 398         case ETHERTYPE_ATALK:
 399                 if (ndo->ndo_vflag)
 400                         ND_PRINT("et1 ");
 401                 atalk_print(ndo, p, length);
 402                 return (1);
 403
 404         case ETHERTYPE_AARP:
 405                 aarp_print(ndo, p, length);
 406                 return (1);
 407
 408         case ETHERTYPE_IPX:
 409                 ND_PRINT("(NOV-ETHII) ");
 410                 ipx_print(ndo, p, length);
 411                 return (1);
 412
 413         case ETHERTYPE_ISO:
 414                 if (length == 0 || caplen == 0) {
 415                         ndo->ndo_protocol = "isoclns";
 416                         nd_print_trunc(ndo);
 417                         return (1);
 418                 }
 419                 isoclns_print(ndo, p + 1, length - 1);
 420                 return(1);
 421
 422         case ETHERTYPE_PPPOED:
 423         case ETHERTYPE_PPPOES:
 424         case ETHERTYPE_PPPOED2:
 425         case ETHERTYPE_PPPOES2:
 426                 pppoe_print(ndo, p, length);
 427                 return (1);
 428
 429         case ETHERTYPE_EAPOL:
 430                 eap_print(ndo, p, length);
 431                 return (1);
 432
 433         case ETHERTYPE_RRCP:
 434                 rrcp_print(ndo, p, length, src, dst);
 435                 return (1);
 436
 437         case ETHERTYPE_PPP:
 438                 if (length) {
 439                         ND_PRINT(": ");
 440                         ppp_print(ndo, p, length);
 441                 }
 442                 return (1);
 443
 444         case ETHERTYPE_MPCP:
 445                 mpcp_print(ndo, p, length);
 446                 return (1);
 447
 448         case ETHERTYPE_SLOW:
 449                 slow_print(ndo, p, length);
 450                 return (1);
 451
 452         case ETHERTYPE_CFM:
 453         case ETHERTYPE_CFM_OLD:
 454                 cfm_print(ndo, p, length);
 455                 return (1);
 456
 457         case ETHERTYPE_LLDP:
 458                 lldp_print(ndo, p, length);
 459                 return (1);
 460
 461         case ETHERTYPE_NSH:
 462                 nsh_print(ndo, p, length);
 463                 return (1);
 464
 465         case ETHERTYPE_LOOPBACK:
 466                 loopback_print(ndo, p, length);
 467                 return (1);
 468
 469         case ETHERTYPE_MPLS:
 470         case ETHERTYPE_MPLS_MULTI:
 471                 mpls_print(ndo, p, length);
 472                 return (1);
 473
 474         case ETHERTYPE_TIPC:
 475                 tipc_print(ndo, p, length, caplen);
 476                 return (1);
 477
 478         case ETHERTYPE_MS_NLB_HB:
 479                 msnlb_print(ndo, p);
 480                 return (1);
 481
 482         case ETHERTYPE_GEONET_OLD:
 483         case ETHERTYPE_GEONET:
 484                 geonet_print(ndo, p, length, src);
 485                 return (1);
 486
 487         case ETHERTYPE_CALM_FAST:
 488                 calm_fast_print(ndo, p, length, src);
 489                 return (1);
 490
 491         case ETHERTYPE_AOE:
 492                 aoe_print(ndo, p, length);
 493                 return (1);
 494
 495         case ETHERTYPE_LAT:
 496         case ETHERTYPE_SCA:
 497         case ETHERTYPE_MOPRC:
 498         case ETHERTYPE_MOPDL:
 499         case ETHERTYPE_IEEE1905_1:
 500                 /* default_print for now */
 501         default:
 502                 return (0);
 503         }
 504 }