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     { ETHERTYPE_MEDSA,          "MEDSA" },
 104     { 0, NULL}
 105 };
 106
 107 static void
 108 ether_hdr_print(netdissect_options *ndo,
 109                 const u_char *bp, u_int length,
 110                 u_int hdrlen)
 111 {
 112         const struct ether_header *ehp;
 113         uint16_t length_type;
 114
 115         ehp = (const struct ether_header *)bp;
 116
 117         ND_PRINT("%s > %s",
 118                  etheraddr_string(ndo, ehp->ether_shost),
 119                  etheraddr_string(ndo, ehp->ether_dhost));
 120
 121         length_type = GET_BE_U_2(bp + (hdrlen - sizeof(ehp->ether_length_type)));
 122         if (!ndo->ndo_qflag) {
 123                 if (length_type <= MAX_ETHERNET_LENGTH_VAL) {
 124                         ND_PRINT(", 802.3");
 125                         length = length_type;
 126                 } else
 127                         ND_PRINT(", ethertype %s (0x%04x)",
 128                                  tok2str(ethertype_values,"Unknown", length_type),
 129                                  length_type);
 130         } else {
 131                 if (length_type <= MAX_ETHERNET_LENGTH_VAL) {
 132                         ND_PRINT(", 802.3");
 133                         length = length_type;
 134                 } else
 135                         ND_PRINT(", %s", tok2str(ethertype_values,"Unknown Ethertype (0x%04x)", length_type));
 136         }
 137
 138         ND_PRINT(", length %u: ", length);
 139 }
 140
 141 /*
 142  * Print an Ethernet frame while specyfing a non-standard Ethernet header
 143  * length.
 144  * This might be encapsulated within another frame; we might be passed
 145  * a pointer to a function that can print header information for that
 146  * frame's protocol, and an argument to pass to that function.
 147  *
 148  * FIXME: caplen can and should be derived from ndo->ndo_snapend and p.
 149  */
 150 u_int
 151 ether_print_hdr_len(netdissect_options *ndo,
 152                     const u_char *p, u_int length, u_int caplen,
 153                     void (*print_encap_header)(netdissect_options *ndo, const u_char *),
 154                     const u_char *encap_header_arg, u_int hdrlen)
 155 {
 156         const struct ether_header *ehp;
 157         u_int orig_length;
 158         u_short length_type;
 159         int llc_hdrlen;
 160         struct lladdr_info src, dst;
 161
 162         /* Unless specified otherwise, assume a standard Ethernet header */
 163         if (hdrlen == ETHER_HDRLEN)
 164                 ndo->ndo_protocol = "ether";
 165
 166         if (caplen < hdrlen) {
 167                 nd_print_trunc(ndo);
 168                 return (caplen);
 169         }
 170         if (length < hdrlen) {
 171                 nd_print_trunc(ndo);
 172                 return (length);
 173         }
 174
 175         /* If the offset is set, then the upper printer is responsible for
 176          * printing the relevant part of the Ethernet header.
 177          */
 178         if (ndo->ndo_eflag) {
 179                 if (print_encap_header != NULL)
 180                         (*print_encap_header)(ndo, encap_header_arg);
 181                 ether_hdr_print(ndo, p, length, hdrlen);
 182         }
 183
 184         orig_length = length;
 185
 186         length -= hdrlen;
 187         caplen -= hdrlen;
 188         ehp = (const struct ether_header *)p;
 189         p += hdrlen;
 190
 191         src.addr = ehp->ether_shost;
 192         src.addr_string = etheraddr_string;
 193         dst.addr = ehp->ether_dhost;
 194         dst.addr_string = etheraddr_string;
 195         length_type = GET_BE_U_2((const u_char *)ehp + (hdrlen - sizeof(ehp->ether_length_type)));
 196
 197 recurse:
 198         /*
 199          * Is it (gag) an 802.3 encapsulation?
 200          */
 201         if (length_type <= MAX_ETHERNET_LENGTH_VAL) {
 202                 /* Try to print the LLC-layer header & higher layers */
 203                 llc_hdrlen = llc_print(ndo, p, length, caplen, &src, &dst);
 204                 if (llc_hdrlen < 0) {
 205                         /* packet type not known, print raw packet */
 206                         if (!ndo->ndo_suppress_default_print)
 207                                 ND_DEFAULTPRINT(p, caplen);
 208                         llc_hdrlen = -llc_hdrlen;
 209                 }
 210                 hdrlen += llc_hdrlen;
 211         } else if (length_type == ETHERTYPE_8021Q  ||
 212                 length_type == ETHERTYPE_8021Q9100 ||
 213                 length_type == ETHERTYPE_8021Q9200 ||
 214                 length_type == ETHERTYPE_8021QinQ) {
 215                 /*
 216                  * Print VLAN information, and then go back and process
 217                  * the enclosed type field.
 218                  */
 219                 if (caplen < 4) {
 220                         ndo->ndo_protocol = "vlan";
 221                         nd_print_trunc(ndo);
 222                         return (hdrlen + caplen);
 223                 }
 224                 if (length < 4) {
 225                         ndo->ndo_protocol = "vlan";
 226                         nd_print_trunc(ndo);
 227                         return (hdrlen + length);
 228                 }
 229                 if (ndo->ndo_eflag) {
 230                         uint16_t tag = GET_BE_U_2(p);
 231
 232                         ND_PRINT("%s, ", ieee8021q_tci_string(tag));
 233                 }
 234
 235                 length_type = GET_BE_U_2(p + 2);
 236                 if (ndo->ndo_eflag && length_type > MAX_ETHERNET_LENGTH_VAL)
 237                         ND_PRINT("ethertype %s, ", tok2str(ethertype_values,"0x%04x", length_type));
 238                 p += 4;
 239                 length -= 4;
 240                 caplen -= 4;
 241                 hdrlen += 4;
 242                 goto recurse;
 243         } else if (length_type == ETHERTYPE_JUMBO) {
 244                 /*
 245                  * Alteon jumbo frames.
 246                  * See
 247                  *
 248                  *      http://tools.ietf.org/html/draft-ietf-isis-ext-eth-01
 249                  *
 250                  * which indicates that, following the type field,
 251                  * there's an LLC header and payload.
 252                  */
 253                 /* Try to print the LLC-layer header & higher layers */
 254                 llc_hdrlen = llc_print(ndo, p, length, caplen, &src, &dst);
 255                 if (llc_hdrlen < 0) {
 256                         /* packet type not known, print raw packet */
 257                         if (!ndo->ndo_suppress_default_print)
 258                                 ND_DEFAULTPRINT(p, caplen);
 259                         llc_hdrlen = -llc_hdrlen;
 260                 }
 261                 hdrlen += llc_hdrlen;
 262         } else {
 263                 if (ethertype_print(ndo, length_type, p, length, caplen, &src, &dst) == 0) {
 264                         /* type not known, print raw packet */
 265                         if (!ndo->ndo_eflag) {
 266                                 if (print_encap_header != NULL)
 267                                         (*print_encap_header)(ndo, encap_header_arg);
 268                                 ether_hdr_print(ndo, (const u_char *)ehp, orig_length,
 269                                                 hdrlen);
 270                         }
 271
 272                         if (!ndo->ndo_suppress_default_print)
 273                                 ND_DEFAULTPRINT(p, caplen);
 274                 }
 275         }
 276         return (hdrlen);
 277 }
 278
 279 /*
 280  * Print an Ethernet frame.
 281  * This might be encapsulated within another frame; we might be passed
 282  * a pointer to a function that can print header information for that
 283  * frame's protocol, and an argument to pass to that function.
 284  *
 285  * FIXME: caplen can and should be derived from ndo->ndo_snapend and p.
 286  */
 287 u_int
 288 ether_print(netdissect_options *ndo,
 289             const u_char *p, u_int length, u_int caplen,
 290             void (*print_encap_header)(netdissect_options *ndo, const u_char *),
 291             const u_char *encap_header_arg)
 292 {
 293         return (ether_print_hdr_len(ndo, p, length, caplen,
 294                                     print_encap_header, encap_header_arg,
 295                                     ETHER_HDRLEN));
 296 }
 297
 298 /*
 299  * This is the top level routine of the printer.  'p' points
 300  * to the ether header of the packet, 'h->len' is the length
 301  * of the packet off the wire, and 'h->caplen' is the number
 302  * of bytes actually captured.
 303  */
 304 u_int
 305 ether_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h,
 306                const u_char *p)
 307 {
 308         ndo->ndo_protocol = "ether_if";
 309         return (ether_print(ndo, p, h->len, h->caplen, NULL, NULL));
 310 }
 311
 312 /*
 313  * This is the top level routine of the printer.  'p' points
 314  * to the ether header of the packet, 'h->len' is the length
 315  * of the packet off the wire, and 'h->caplen' is the number
 316  * of bytes actually captured.
 317  *
 318  * This is for DLT_NETANALYZER, which has a 4-byte pseudo-header
 319  * before the Ethernet header.
 320  */
 321 u_int
 322 netanalyzer_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h,
 323                      const u_char *p)
 324 {
 325         /*
 326          * Fail if we don't have enough data for the Hilscher pseudo-header.
 327          */
 328         ndo->ndo_protocol = "netanalyzer_if";
 329         if (h->caplen < 4) {
 330                 nd_print_trunc(ndo);
 331                 return (h->caplen);
 332         }
 333
 334         /* Skip the pseudo-header. */
 335         return (4 + ether_print(ndo, p + 4, h->len - 4, h->caplen - 4, NULL, NULL));
 336 }
 337
 338 /*
 339  * This is the top level routine of the printer.  'p' points
 340  * to the ether header of the packet, 'h->len' is the length
 341  * of the packet off the wire, and 'h->caplen' is the number
 342  * of bytes actually captured.
 343  *
 344  * This is for DLT_NETANALYZER_TRANSPARENT, which has a 4-byte
 345  * pseudo-header, a 7-byte Ethernet preamble, and a 1-byte Ethernet SOF
 346  * before the Ethernet header.
 347  */
 348 u_int
 349 netanalyzer_transparent_if_print(netdissect_options *ndo,
 350                                  const struct pcap_pkthdr *h,
 351                                  const u_char *p)
 352 {
 353         /*
 354          * Fail if we don't have enough data for the Hilscher pseudo-header,
 355          * preamble, and SOF.
 356          */
 357         ndo->ndo_protocol = "netanalyzer_transparent_if";
 358         if (h->caplen < 12) {
 359                 nd_print_trunc(ndo);
 360                 return (h->caplen);
 361         }
 362
 363         /* Skip the pseudo-header, preamble, and SOF. */
 364         return (12 + ether_print(ndo, p + 12, h->len - 12, h->caplen - 12, NULL, NULL));
 365 }
 366
 367 /*
 368  * Prints the packet payload, given an Ethernet type code for the payload's
 369  * protocol.
 370  *
 371  * Returns non-zero if it can do so, zero if the ethertype is unknown.
 372  */
 373
 374 int
 375 ethertype_print(netdissect_options *ndo,
 376                 u_short ether_type, const u_char *p,
 377                 u_int length, u_int caplen,
 378                 const struct lladdr_info *src, const struct lladdr_info *dst)
 379 {
 380         switch (ether_type) {
 381
 382         case ETHERTYPE_IP:
 383                 ip_print(ndo, p, length);
 384                 return (1);
 385
 386         case ETHERTYPE_IPV6:
 387                 ip6_print(ndo, p, length);
 388                 return (1);
 389
 390         case ETHERTYPE_ARP:
 391         case ETHERTYPE_REVARP:
 392                 arp_print(ndo, p, length, caplen);
 393                 return (1);
 394
 395         case ETHERTYPE_DN:
 396                 decnet_print(ndo, p, length, caplen);
 397                 return (1);
 398
 399         case ETHERTYPE_ATALK:
 400                 if (ndo->ndo_vflag)
 401                         ND_PRINT("et1 ");
 402                 atalk_print(ndo, p, length);
 403                 return (1);
 404
 405         case ETHERTYPE_AARP:
 406                 aarp_print(ndo, p, length);
 407                 return (1);
 408
 409         case ETHERTYPE_IPX:
 410                 ND_PRINT("(NOV-ETHII) ");
 411                 ipx_print(ndo, p, length);
 412                 return (1);
 413
 414         case ETHERTYPE_ISO:
 415                 if (length == 0 || caplen == 0) {
 416                         ndo->ndo_protocol = "isoclns";
 417                         nd_print_trunc(ndo);
 418                         return (1);
 419                 }
 420                 isoclns_print(ndo, p + 1, length - 1);
 421                 return(1);
 422
 423         case ETHERTYPE_PPPOED:
 424         case ETHERTYPE_PPPOES:
 425         case ETHERTYPE_PPPOED2:
 426         case ETHERTYPE_PPPOES2:
 427                 pppoe_print(ndo, p, length);
 428                 return (1);
 429
 430         case ETHERTYPE_EAPOL:
 431                 eap_print(ndo, p, length);
 432                 return (1);
 433
 434         case ETHERTYPE_RRCP:
 435                 rrcp_print(ndo, p, length, src, dst);
 436                 return (1);
 437
 438         case ETHERTYPE_PPP:
 439                 if (length) {
 440                         ND_PRINT(": ");
 441                         ppp_print(ndo, p, length);
 442                 }
 443                 return (1);
 444
 445         case ETHERTYPE_MPCP:
 446                 mpcp_print(ndo, p, length);
 447                 return (1);
 448
 449         case ETHERTYPE_SLOW:
 450                 slow_print(ndo, p, length);
 451                 return (1);
 452
 453         case ETHERTYPE_CFM:
 454         case ETHERTYPE_CFM_OLD:
 455                 cfm_print(ndo, p, length);
 456                 return (1);
 457
 458         case ETHERTYPE_LLDP:
 459                 lldp_print(ndo, p, length);
 460                 return (1);
 461
 462         case ETHERTYPE_NSH:
 463                 nsh_print(ndo, p, length);
 464                 return (1);
 465
 466         case ETHERTYPE_LOOPBACK:
 467                 loopback_print(ndo, p, length);
 468                 return (1);
 469
 470         case ETHERTYPE_MPLS:
 471         case ETHERTYPE_MPLS_MULTI:
 472                 mpls_print(ndo, p, length);
 473                 return (1);
 474
 475         case ETHERTYPE_TIPC:
 476                 tipc_print(ndo, p, length, caplen);
 477                 return (1);
 478
 479         case ETHERTYPE_MS_NLB_HB:
 480                 msnlb_print(ndo, p);
 481                 return (1);
 482
 483         case ETHERTYPE_GEONET_OLD:
 484         case ETHERTYPE_GEONET:
 485                 geonet_print(ndo, p, length, src);
 486                 return (1);
 487
 488         case ETHERTYPE_CALM_FAST:
 489                 calm_fast_print(ndo, p, length, src);
 490                 return (1);
 491
 492         case ETHERTYPE_AOE:
 493                 aoe_print(ndo, p, length);
 494                 return (1);
 495
 496         case ETHERTYPE_MEDSA:
 497                 medsa_print(ndo, p, length, caplen, src, dst);
 498                 return (1);
 499
 500         case ETHERTYPE_LAT:
 501         case ETHERTYPE_SCA:
 502         case ETHERTYPE_MOPRC:
 503         case ETHERTYPE_MOPDL:
 504         case ETHERTYPE_IEEE1905_1:
 505                 /* default_print for now */
 506         default:
 507                 return (0);
 508         }
 509 }