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