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 = EXTRACT_BE_U_2(bp +
 122                                      (hdrlen - sizeof(ehp->ether_length_type)));
 123         if (!ndo->ndo_qflag) {
 124                 if (length_type <= MAX_ETHERNET_LENGTH_VAL) {
 125                         ND_PRINT(", 802.3");
 126                         length = length_type;
 127                 } else
 128                         ND_PRINT(", ethertype %s (0x%04x)",
 129                                        tok2str(ethertype_values,"Unknown", length_type),
 130                                        length_type);
 131         } else {
 132                 if (length_type <= MAX_ETHERNET_LENGTH_VAL) {
 133                         ND_PRINT(", 802.3");
 134                         length = length_type;
 135                 } else
 136                         ND_PRINT(", %s", tok2str(ethertype_values,"Unknown Ethertype (0x%04x)", length_type));
 137         }
 138
 139         ND_PRINT(", length %u: ", length);
 140 }
 141
 142 /*
 143  * Print an Ethernet frame while specyfing a non-standard Ethernet header
 144  * length.
 145  * This might be encapsulated within another frame; we might be passed
 146  * a pointer to a function that can print header information for that
 147  * frame's protocol, and an argument to pass to that function.
 148  *
 149  * FIXME: caplen can and should be derived from ndo->ndo_snapend and p.
 150  */
 151 u_int
 152 ether_print_hdr_len(netdissect_options *ndo,
 153             const u_char *p, u_int length, u_int caplen,
 154             void (*print_encap_header)(netdissect_options *ndo, const u_char *),
 155             const u_char *encap_header_arg, u_int hdrlen)
 156 {
 157         const struct ether_header *ehp;
 158         u_int orig_length;
 159         u_short length_type;
 160         int llc_hdrlen;
 161         struct lladdr_info src, dst;
 162
 163         /* Unless specified otherwise, assume a standard Ethernet header */
 164         if (hdrlen == ETHER_HDRLEN)
 165                 ndo->ndo_protocol = "ether";
 166
 167         if (caplen < hdrlen) {
 168                 nd_print_trunc(ndo);
 169                 return (caplen);
 170         }
 171         if (length < hdrlen) {
 172                 nd_print_trunc(ndo);
 173                 return (length);
 174         }
 175
 176         /* If the offset is set, then the upper printer is responsible for
 177          * printing the relevant part of the Ethernet header.
 178          */
 179         if (ndo->ndo_eflag) {
 180                 if (print_encap_header != NULL)
 181                         (*print_encap_header)(ndo, encap_header_arg);
 182                 ether_hdr_print(ndo, p, length, hdrlen);
 183         }
 184
 185         orig_length = length;
 186
 187         length -= hdrlen;
 188         caplen -= hdrlen;
 189         ehp = (const struct ether_header *)p;
 190         p += hdrlen;
 191
 192         src.addr = ehp->ether_shost;
 193         src.addr_string = etheraddr_string;
 194         dst.addr = ehp->ether_dhost;
 195         dst.addr_string = etheraddr_string;
 196         length_type = EXTRACT_BE_U_2((const u_char *)ehp +
 197                                      (hdrlen - sizeof(ehp->ether_length_type)));
 198
 199 recurse:
 200         /*
 201          * Is it (gag) an 802.3 encapsulation?
 202          */
 203         if (length_type <= MAX_ETHERNET_LENGTH_VAL) {
 204                 /* Try to print the LLC-layer header & higher layers */
 205                 llc_hdrlen = llc_print(ndo, p, length, caplen, &src, &dst);
 206                 if (llc_hdrlen < 0) {
 207                         /* packet type not known, print raw packet */
 208                         if (!ndo->ndo_suppress_default_print)
 209                                 ND_DEFAULTPRINT(p, caplen);
 210                         llc_hdrlen = -llc_hdrlen;
 211                 }
 212                 hdrlen += llc_hdrlen;
 213         } else if (length_type == ETHERTYPE_8021Q  ||
 214                 length_type == ETHERTYPE_8021Q9100 ||
 215                 length_type == ETHERTYPE_8021Q9200 ||
 216                 length_type == ETHERTYPE_8021QinQ) {
 217                 /*
 218                  * Print VLAN information, and then go back and process
 219                  * the enclosed type field.
 220                  */
 221                 if (caplen < 4) {
 222                         ndo->ndo_protocol = "vlan";
 223                         nd_print_trunc(ndo);
 224                         return (hdrlen + caplen);
 225                 }
 226                 if (length < 4) {
 227                         ndo->ndo_protocol = "vlan";
 228                         nd_print_trunc(ndo);
 229                         return (hdrlen + length);
 230                 }
 231                 if (ndo->ndo_eflag) {
 232                         uint16_t tag = EXTRACT_BE_U_2(p);
 233
 234                         ND_PRINT("%s, ", ieee8021q_tci_string(tag));
 235                 }
 236
 237                 length_type = EXTRACT_BE_U_2(p + 2);
 238                 if (ndo->ndo_eflag && length_type > MAX_ETHERNET_LENGTH_VAL)
 239                         ND_PRINT("ethertype %s, ", tok2str(ethertype_values,"0x%04x", length_type));
 240                 p += 4;
 241                 length -= 4;
 242                 caplen -= 4;
 243                 hdrlen += 4;
 244                 goto recurse;
 245         } else if (length_type == ETHERTYPE_JUMBO) {
 246                 /*
 247                  * Alteon jumbo frames.
 248                  * See
 249                  *
 250                  *      http://tools.ietf.org/html/draft-ietf-isis-ext-eth-01
 251                  *
 252                  * which indicates that, following the type field,
 253                  * there's an LLC header and payload.
 254                  */
 255                 /* Try to print the LLC-layer header & higher layers */
 256                 llc_hdrlen = llc_print(ndo, p, length, caplen, &src, &dst);
 257                 if (llc_hdrlen < 0) {
 258                         /* packet type not known, print raw packet */
 259                         if (!ndo->ndo_suppress_default_print)
 260                                 ND_DEFAULTPRINT(p, caplen);
 261                         llc_hdrlen = -llc_hdrlen;
 262                 }
 263                 hdrlen += llc_hdrlen;
 264         } else {
 265                 if (ethertype_print(ndo, length_type, p, length, caplen, &src, &dst) == 0) {
 266                         /* type not known, print raw packet */
 267                         if (!ndo->ndo_eflag) {
 268                                 if (print_encap_header != NULL)
 269                                         (*print_encap_header)(ndo, encap_header_arg);
 270                                 ether_hdr_print(ndo, (const u_char *)ehp, orig_length,
 271                                                 hdrlen);
 272                         }
 273
 274                         if (!ndo->ndo_suppress_default_print)
 275                                 ND_DEFAULTPRINT(p, caplen);
 276                 }
 277         }
 278         return (hdrlen);
 279 }
 280
 281 /*
 282  * Print an Ethernet frame.
 283  * This might be encapsulated within another frame; we might be passed
 284  * a pointer to a function that can print header information for that
 285  * frame's protocol, and an argument to pass to that function.
 286  *
 287  * FIXME: caplen can and should be derived from ndo->ndo_snapend and p.
 288  */
 289 u_int
 290 ether_print(netdissect_options *ndo,
 291             const u_char *p, u_int length, u_int caplen,
 292             void (*print_encap_header)(netdissect_options *ndo, const u_char *),
 293             const u_char *encap_header_arg)
 294 {
 295         return (ether_print_hdr_len(ndo, p, length, caplen,
 296                                           print_encap_header, encap_header_arg,
 297                                           ETHER_HDRLEN));
 298 }
 299
 300 /*
 301  * This is the top level routine of the printer.  'p' points
 302  * to the ether header of the packet, 'h->len' is the length
 303  * of the packet off the wire, and 'h->caplen' is the number
 304  * of bytes actually captured.
 305  */
 306 u_int
 307 ether_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h,
 308                const u_char *p)
 309 {
 310         ndo->ndo_protocol = "ether_if";
 311         return (ether_print(ndo, p, h->len, h->caplen, NULL, NULL));
 312 }
 313
 314 /*
 315  * This is the top level routine of the printer.  'p' points
 316  * to the ether header of the packet, 'h->len' is the length
 317  * of the packet off the wire, and 'h->caplen' is the number
 318  * of bytes actually captured.
 319  *
 320  * This is for DLT_NETANALYZER, which has a 4-byte pseudo-header
 321  * before the Ethernet header.
 322  */
 323 u_int
 324 netanalyzer_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h,
 325                      const u_char *p)
 326 {
 327         /*
 328          * Fail if we don't have enough data for the Hilscher pseudo-header.
 329          */
 330         ndo->ndo_protocol = "netanalyzer_if";
 331         if (h->caplen < 4) {
 332                 nd_print_trunc(ndo);
 333                 return (h->caplen);
 334         }
 335
 336         /* Skip the pseudo-header. */
 337         return (4 + ether_print(ndo, p + 4, h->len - 4, h->caplen - 4, NULL, NULL));
 338 }
 339
 340 /*
 341  * This is the top level routine of the printer.  'p' points
 342  * to the ether header of the packet, 'h->len' is the length
 343  * of the packet off the wire, and 'h->caplen' is the number
 344  * of bytes actually captured.
 345  *
 346  * This is for DLT_NETANALYZER_TRANSPARENT, which has a 4-byte
 347  * pseudo-header, a 7-byte Ethernet preamble, and a 1-byte Ethernet SOF
 348  * before the Ethernet header.
 349  */
 350 u_int
 351 netanalyzer_transparent_if_print(netdissect_options *ndo,
 352                                  const struct pcap_pkthdr *h,
 353                                  const u_char *p)
 354 {
 355         /*
 356          * Fail if we don't have enough data for the Hilscher pseudo-header,
 357          * preamble, and SOF.
 358          */
 359         ndo->ndo_protocol = "netanalyzer_transparent_if";
 360         if (h->caplen < 12) {
 361                 nd_print_trunc(ndo);
 362                 return (h->caplen);
 363         }
 364
 365         /* Skip the pseudo-header, preamble, and SOF. */
 366         return (12 + ether_print(ndo, p + 12, h->len - 12, h->caplen - 12, NULL, NULL));
 367 }
 368
 369 /*
 370  * Prints the packet payload, given an Ethernet type code for the payload's
 371  * protocol.
 372  *
 373  * Returns non-zero if it can do so, zero if the ethertype is unknown.
 374  */
 375
 376 int
 377 ethertype_print(netdissect_options *ndo,
 378                 u_short ether_type, const u_char *p,
 379                 u_int length, u_int caplen,
 380                 const struct lladdr_info *src, const struct lladdr_info *dst)
 381 {
 382         switch (ether_type) {
 383
 384         case ETHERTYPE_IP:
 385                 ip_print(ndo, p, length);
 386                 return (1);
 387
 388         case ETHERTYPE_IPV6:
 389                 ip6_print(ndo, p, length);
 390                 return (1);
 391
 392         case ETHERTYPE_ARP:
 393         case ETHERTYPE_REVARP:
 394                 arp_print(ndo, p, length, caplen);
 395                 return (1);
 396
 397         case ETHERTYPE_DN:
 398                 decnet_print(ndo, p, length, caplen);
 399                 return (1);
 400
 401         case ETHERTYPE_ATALK:
 402                 if (ndo->ndo_vflag)
 403                         ND_PRINT("et1 ");
 404                 atalk_print(ndo, p, length);
 405                 return (1);
 406
 407         case ETHERTYPE_AARP:
 408                 aarp_print(ndo, p, length);
 409                 return (1);
 410
 411         case ETHERTYPE_IPX:
 412                 ND_PRINT("(NOV-ETHII) ");
 413                 ipx_print(ndo, p, length);
 414                 return (1);
 415
 416         case ETHERTYPE_ISO:
 417                 if (length == 0 || caplen == 0) {
 418                         ndo->ndo_protocol = "isoclns";
 419                         nd_print_trunc(ndo);
 420                         return (1);
 421                 }
 422                 isoclns_print(ndo, p + 1, length - 1);
 423                 return(1);
 424
 425         case ETHERTYPE_PPPOED:
 426         case ETHERTYPE_PPPOES:
 427         case ETHERTYPE_PPPOED2:
 428         case ETHERTYPE_PPPOES2:
 429                 pppoe_print(ndo, p, length);
 430                 return (1);
 431
 432         case ETHERTYPE_EAPOL:
 433                 eap_print(ndo, p, length);
 434                 return (1);
 435
 436         case ETHERTYPE_RRCP:
 437                 rrcp_print(ndo, p, length, src, dst);
 438                 return (1);
 439
 440         case ETHERTYPE_PPP:
 441                 if (length) {
 442                         ND_PRINT(": ");
 443                         ppp_print(ndo, p, length);
 444                 }
 445                 return (1);
 446
 447         case ETHERTYPE_MPCP:
 448                 mpcp_print(ndo, p, length);
 449                 return (1);
 450
 451         case ETHERTYPE_SLOW:
 452                 slow_print(ndo, p, length);
 453                 return (1);
 454
 455         case ETHERTYPE_CFM:
 456         case ETHERTYPE_CFM_OLD:
 457                 cfm_print(ndo, p, length);
 458                 return (1);
 459
 460         case ETHERTYPE_LLDP:
 461                 lldp_print(ndo, p, length);
 462                 return (1);
 463
 464         case ETHERTYPE_NSH:
 465                 nsh_print(ndo, p, length);
 466                 return (1);
 467
 468         case ETHERTYPE_LOOPBACK:
 469                 loopback_print(ndo, p, length);
 470                 return (1);
 471
 472         case ETHERTYPE_MPLS:
 473         case ETHERTYPE_MPLS_MULTI:
 474                 mpls_print(ndo, p, length);
 475                 return (1);
 476
 477         case ETHERTYPE_TIPC:
 478                 tipc_print(ndo, p, length, caplen);
 479                 return (1);
 480
 481         case ETHERTYPE_MS_NLB_HB:
 482                 msnlb_print(ndo, p);
 483                 return (1);
 484
 485         case ETHERTYPE_GEONET_OLD:
 486         case ETHERTYPE_GEONET:
 487                 geonet_print(ndo, p, length, src);
 488                 return (1);
 489
 490         case ETHERTYPE_CALM_FAST:
 491                 calm_fast_print(ndo, p, length, src);
 492                 return (1);
 493
 494         case ETHERTYPE_AOE:
 495                 aoe_print(ndo, p, length);
 496                 return (1);
 497
 498         case ETHERTYPE_MEDSA:
 499                 medsa_print(ndo, p, length, caplen, src, dst);
 500                 return (1);
 501
 502         case ETHERTYPE_LAT:
 503         case ETHERTYPE_SCA:
 504         case ETHERTYPE_MOPRC:
 505         case ETHERTYPE_MOPDL:
 506         case ETHERTYPE_IEEE1905_1:
 507                 /* default_print for now */
 508         default:
 509                 return (0);
 510         }
 511 }