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 #ifndef lint
  22 static const char rcsid[] _U_ =
  23     "@(#) $Header: /tcpdump/master/tcpdump/print-ether.c,v 1.106 2008-02-06 10:47:53 guy Exp $ (LBL)";
  24 #endif
  25
  26 #ifdef HAVE_CONFIG_H
  27 #include "config.h"
  28 #endif
  29
  30 #include <tcpdump-stdinc.h>
  31
  32 #include <stdio.h>
  33 #include <pcap.h>
  34
  35 #include "interface.h"
  36 #include "extract.h"
  37 #include "addrtoname.h"
  38 #include "ethertype.h"
  39
  40 #include "ether.h"
  41
  42 const struct tok ethertype_values[] = {
  43     { ETHERTYPE_IP,             "IPv4" },
  44     { ETHERTYPE_MPLS,           "MPLS unicast" },
  45     { ETHERTYPE_MPLS_MULTI,     "MPLS multicast" },
  46     { ETHERTYPE_IPV6,           "IPv6" },
  47     { ETHERTYPE_8021Q,          "802.1Q" },
  48     { ETHERTYPE_VMAN,           "VMAN" },
  49     { ETHERTYPE_PUP,            "PUP" },
  50     { ETHERTYPE_ARP,            "ARP"},
  51     { ETHERTYPE_REVARP,         "Reverse ARP"},
  52     { ETHERTYPE_NS,             "NS" },
  53     { ETHERTYPE_SPRITE,         "Sprite" },
  54     { ETHERTYPE_TRAIL,          "Trail" },
  55     { ETHERTYPE_MOPDL,          "MOP DL" },
  56     { ETHERTYPE_MOPRC,          "MOP RC" },
  57     { ETHERTYPE_DN,             "DN" },
  58     { ETHERTYPE_LAT,            "LAT" },
  59     { ETHERTYPE_SCA,            "SCA" },
  60     { ETHERTYPE_TEB,            "TEB" },
  61     { ETHERTYPE_LANBRIDGE,      "Lanbridge" },
  62     { ETHERTYPE_DECDNS,         "DEC DNS" },
  63     { ETHERTYPE_DECDTS,         "DEC DTS" },
  64     { ETHERTYPE_VEXP,           "VEXP" },
  65     { ETHERTYPE_VPROD,          "VPROD" },
  66     { ETHERTYPE_ATALK,          "Appletalk" },
  67     { ETHERTYPE_AARP,           "Appletalk ARP" },
  68     { ETHERTYPE_IPX,            "IPX" },
  69     { ETHERTYPE_PPP,            "PPP" },
  70     { ETHERTYPE_MPCP,           "MPCP" },
  71     { ETHERTYPE_SLOW,           "Slow Protocols" },
  72     { ETHERTYPE_PPPOED,         "PPPoE D" },
  73     { ETHERTYPE_PPPOES,         "PPPoE S" },
  74     { ETHERTYPE_EAPOL,          "EAPOL" },
  75     { ETHERTYPE_RRCP,           "RRCP" },
  76     { ETHERTYPE_JUMBO,          "Jumbo" },
  77     { ETHERTYPE_LOOPBACK,       "Loopback" },
  78     { ETHERTYPE_ISO,            "OSI" },
  79     { ETHERTYPE_GRE_ISO,        "GRE-OSI" },
  80     { ETHERTYPE_CFM_OLD,        "CFM (old)" },
  81     { ETHERTYPE_CFM,            "CFM" },
  82     { ETHERTYPE_LLDP,           "LLDP" },
  83     { 0, NULL}
  84 };
  85
  86 static inline void
  87 ether_hdr_print(register const u_char *bp, u_int length)
  88 {
  89         register const struct ether_header *ep;
  90         u_int16_t ether_type;
  91
  92         ep = (const struct ether_header *)bp;
  93
  94         (void)printf("%s > %s",
  95                      etheraddr_string(ESRC(ep)),
  96                      etheraddr_string(EDST(ep)));
  97
  98         ether_type = EXTRACT_16BITS(&ep->ether_type);
  99         if (!qflag) {
 100                 if (ether_type <= ETHERMTU)
 101                           (void)printf(", 802.3");
 102                 else
 103                           (void)printf(", ethertype %s (0x%04x)",
 104                                        tok2str(ethertype_values,"Unknown", ether_type),
 105                                        ether_type);
 106         } else {
 107                 if (ether_type <= ETHERMTU)
 108                           (void)printf(", 802.3");
 109                 else
 110                           (void)printf(", %s", tok2str(ethertype_values,"Unknown Ethertype (0x%04x)", ether_type));
 111         }
 112
 113         (void)printf(", length %u: ", length);
 114 }
 115
 116 /*
 117  * Print an Ethernet frame.
 118  * This might be encapsulated within another frame; we might be passed
 119  * a pointer to a function that can print header information for that
 120  * frame's protocol, and an argument to pass to that function.
 121  */
 122 void
 123 ether_print(const u_char *p, u_int length, u_int caplen,
 124     void (*print_encap_header)(const u_char *), const u_char *encap_header_arg)
 125 {
 126         struct ether_header *ep;
 127         u_int orig_length;
 128         u_short ether_type;
 129         u_short extracted_ether_type;
 130
 131         if (caplen < ETHER_HDRLEN || length < ETHER_HDRLEN) {
 132                 printf("[|ether]");
 133                 return;
 134         }
 135
 136         if (eflag) {
 137                 if (print_encap_header != NULL)
 138                         (*print_encap_header)(encap_header_arg);
 139                 ether_hdr_print(p, length);
 140         }
 141         orig_length = length;
 142
 143         length -= ETHER_HDRLEN;
 144         caplen -= ETHER_HDRLEN;
 145         ep = (struct ether_header *)p;
 146         p += ETHER_HDRLEN;
 147
 148         ether_type = EXTRACT_16BITS(&ep->ether_type);
 149
 150 recurse:
 151         /*
 152          * Is it (gag) an 802.3 encapsulation?
 153          */
 154         if (ether_type <= ETHERMTU) {
 155                 /* Try to print the LLC-layer header & higher layers */
 156                 if (llc_print(p, length, caplen, ESRC(ep), EDST(ep),
 157                     &extracted_ether_type) == 0) {
 158                         /* ether_type not known, print raw packet */
 159                         if (!eflag) {
 160                                 if (print_encap_header != NULL)
 161                                         (*print_encap_header)(encap_header_arg);
 162                                 ether_hdr_print((u_char *)ep, orig_length);
 163                         }
 164
 165                         if (!suppress_default_print)
 166                                 default_print(p, caplen);
 167                 }
 168         } else if (ether_type == ETHERTYPE_8021Q) {
 169                 /*
 170                  * Print VLAN information, and then go back and process
 171                  * the enclosed type field.
 172                  */
 173                 if (caplen < 4 || length < 4) {
 174                         printf("[|vlan]");
 175                         return;
 176                 }
 177                 if (eflag) {
 178                         u_int16_t tag = EXTRACT_16BITS(p);
 179
 180                         printf("vlan %u, p %u%s, ",
 181                             tag & 0xfff,
 182                             tag >> 13,
 183                             (tag & 0x1000) ? ", CFI" : "");
 184                 }
 185
 186                 ether_type = EXTRACT_16BITS(p + 2);
 187                 if (eflag && ether_type > ETHERMTU)
 188                         printf("ethertype %s, ", tok2str(ethertype_values,"0x%04x", ether_type));
 189                 p += 4;
 190                 length -= 4;
 191                 caplen -= 4;
 192                 goto recurse;
 193         } else if (ether_type == ETHERTYPE_JUMBO) {
 194                 /*
 195                  * Alteon jumbo frames.
 196                  * See
 197                  *
 198                  *      http://tools.ietf.org/html/draft-ietf-isis-ext-eth-01
 199                  *
 200                  * which indicates that, following the type field,
 201                  * there's an LLC header and payload.
 202                  */
 203                 /* Try to print the LLC-layer header & higher layers */
 204                 if (llc_print(p, length, caplen, ESRC(ep), EDST(ep),
 205                     &extracted_ether_type) == 0) {
 206                         /* ether_type not known, print raw packet */
 207                         if (!eflag) {
 208                                 if (print_encap_header != NULL)
 209                                         (*print_encap_header)(encap_header_arg);
 210                                 ether_hdr_print((u_char *)ep, orig_length);
 211                         }
 212
 213                         if (!suppress_default_print)
 214                                 default_print(p, caplen);
 215                 }
 216         } else {
 217                 if (ethertype_print(ether_type, p, length, caplen) == 0) {
 218                         /* ether_type not known, print raw packet */
 219                         if (!eflag) {
 220                                 if (print_encap_header != NULL)
 221                                         (*print_encap_header)(encap_header_arg);
 222                                 ether_hdr_print((u_char *)ep, orig_length);
 223                         }
 224
 225                         if (!suppress_default_print)
 226                                 default_print(p, caplen);
 227                 }
 228         }
 229 }
 230
 231 /*
 232  * This is the top level routine of the printer.  'p' points
 233  * to the ether header of the packet, 'h->ts' is the timestamp,
 234  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
 235  * is the number of bytes actually captured.
 236  */
 237 u_int
 238 ether_if_print(const struct pcap_pkthdr *h, const u_char *p)
 239 {
 240         ether_print(p, h->len, h->caplen, NULL, NULL);
 241
 242         return (ETHER_HDRLEN);
 243 }
 244
 245 /*
 246  * Prints the packet payload, given an Ethernet type code for the payload's
 247  * protocol.
 248  *
 249  * Returns non-zero if it can do so, zero if the ethertype is unknown.
 250  */
 251
 252 int
 253 ethertype_print(u_short ether_type, const u_char *p, u_int length, u_int caplen)
 254 {
 255         switch (ether_type) {
 256
 257         case ETHERTYPE_IP:
 258                 ip_print(gndo, p, length);
 259                 return (1);
 260
 261 #ifdef INET6
 262         case ETHERTYPE_IPV6:
 263                 ip6_print(p, length);
 264                 return (1);
 265 #endif /*INET6*/
 266
 267         case ETHERTYPE_ARP:
 268         case ETHERTYPE_REVARP:
 269                 arp_print(gndo, p, length, caplen);
 270                 return (1);
 271
 272         case ETHERTYPE_DN:
 273                 decnet_print(p, length, caplen);
 274                 return (1);
 275
 276         case ETHERTYPE_ATALK:
 277                 if (vflag)
 278                         fputs("et1 ", stdout);
 279                 atalk_print(p, length);
 280                 return (1);
 281
 282         case ETHERTYPE_AARP:
 283                 aarp_print(p, length);
 284                 return (1);
 285
 286         case ETHERTYPE_IPX:
 287                 printf("(NOV-ETHII) ");
 288                 ipx_print(p, length);
 289                 return (1);
 290
 291         case ETHERTYPE_ISO:
 292                 isoclns_print(p+1, length-1, length-1);
 293                 return(1);
 294
 295         case ETHERTYPE_PPPOED:
 296         case ETHERTYPE_PPPOES:
 297         case ETHERTYPE_PPPOED2:
 298         case ETHERTYPE_PPPOES2:
 299                 pppoe_print(p, length);
 300                 return (1);
 301
 302         case ETHERTYPE_EAPOL:
 303                 eap_print(gndo, p, length);
 304                 return (1);
 305
 306         case ETHERTYPE_RRCP:
 307                 rrcp_print(gndo, p - 14 , length + 14);
 308                 return (1);
 309
 310         case ETHERTYPE_PPP:
 311                 if (length) {
 312                         printf(": ");
 313                         ppp_print(p, length);
 314                 }
 315                 return (1);
 316
 317         case ETHERTYPE_MPCP:
 318                 mpcp_print(p, length);
 319                 return (1);
 320
 321         case ETHERTYPE_SLOW:
 322                 slow_print(p, length);
 323                 return (1);
 324
 325         case ETHERTYPE_CFM:
 326         case ETHERTYPE_CFM_OLD:
 327                 cfm_print(p, length);
 328                 return (1);
 329
 330         case ETHERTYPE_LLDP:
 331                 lldp_print(p, length);
 332                 return (1);
 333
 334         case ETHERTYPE_LOOPBACK:
 335                 return (1);
 336
 337         case ETHERTYPE_MPLS:
 338         case ETHERTYPE_MPLS_MULTI:
 339                 mpls_print(p, length);
 340                 return (1);
 341
 342         case ETHERTYPE_LAT:
 343         case ETHERTYPE_SCA:
 344         case ETHERTYPE_MOPRC:
 345         case ETHERTYPE_MOPDL:
 346                 /* default_print for now */
 347         default:
 348                 return (0);
 349         }
 350 }
 351
 352
 353 /*
 354  * Local Variables:
 355  * c-style: whitesmith
 356  * c-basic-offset: 8
 357  * End:
 358  */
 359