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 "addrtoname.h"
  37 #include "ethertype.h"
  38
  39 #include "ether.h"
  40
  41 const struct tok ethertype_values[] = {
  42     { ETHERTYPE_IP,             "IPv4" },
  43     { ETHERTYPE_MPLS,           "MPLS unicast" },
  44     { ETHERTYPE_MPLS_MULTI,     "MPLS multicast" },
  45     { ETHERTYPE_IPV6,           "IPv6" },
  46     { ETHERTYPE_8021Q,          "802.1Q" },
  47     { ETHERTYPE_VMAN,           "VMAN" },
  48     { ETHERTYPE_PUP,            "PUP" },
  49     { ETHERTYPE_ARP,            "ARP"},
  50     { ETHERTYPE_REVARP,         "Reverse ARP"},
  51     { ETHERTYPE_NS,             "NS" },
  52     { ETHERTYPE_SPRITE,         "Sprite" },
  53     { ETHERTYPE_TRAIL,          "Trail" },
  54     { ETHERTYPE_MOPDL,          "MOP DL" },
  55     { ETHERTYPE_MOPRC,          "MOP RC" },
  56     { ETHERTYPE_DN,             "DN" },
  57     { ETHERTYPE_LAT,            "LAT" },
  58     { ETHERTYPE_SCA,            "SCA" },
  59     { ETHERTYPE_TEB,            "TEB" },
  60     { ETHERTYPE_LANBRIDGE,      "Lanbridge" },
  61     { ETHERTYPE_DECDNS,         "DEC DNS" },
  62     { ETHERTYPE_DECDTS,         "DEC DTS" },
  63     { ETHERTYPE_VEXP,           "VEXP" },
  64     { ETHERTYPE_VPROD,          "VPROD" },
  65     { ETHERTYPE_ATALK,          "Appletalk" },
  66     { ETHERTYPE_AARP,           "Appletalk ARP" },
  67     { ETHERTYPE_IPX,            "IPX" },
  68     { ETHERTYPE_PPP,            "PPP" },
  69     { ETHERTYPE_MPCP,           "MPCP" },
  70     { ETHERTYPE_SLOW,           "Slow Protocols" },
  71     { ETHERTYPE_PPPOED,         "PPPoE D" },
  72     { ETHERTYPE_PPPOES,         "PPPoE S" },
  73     { ETHERTYPE_EAPOL,          "EAPOL" },
  74     { ETHERTYPE_RRCP,           "RRCP" },
  75     { ETHERTYPE_JUMBO,          "Jumbo" },
  76     { ETHERTYPE_LOOPBACK,       "Loopback" },
  77     { ETHERTYPE_ISO,            "OSI" },
  78     { ETHERTYPE_GRE_ISO,        "GRE-OSI" },
  79     { ETHERTYPE_CFM_OLD,        "CFM (old)" },
  80     { ETHERTYPE_CFM,            "CFM" },
  81     { ETHERTYPE_LLDP,           "LLDP" },
  82     { 0, NULL}
  83 };
  84
  85 static inline void
  86 ether_hdr_print(register const u_char *bp, u_int length)
  87 {
  88         register const struct ether_header *ep;
  89         ep = (const struct ether_header *)bp;
  90
  91         (void)printf("%s > %s",
  92                      etheraddr_string(ESRC(ep)),
  93                      etheraddr_string(EDST(ep)));
  94
  95         if (!qflag) {
  96                 if (ntohs(ep->ether_type) <= ETHERMTU)
  97                           (void)printf(", 802.3");
  98                 else
  99                           (void)printf(", ethertype %s (0x%04x)",
 100                                        tok2str(ethertype_values,"Unknown", ntohs(ep->ether_type)),
 101                                        ntohs(ep->ether_type));
 102         } else {
 103                 if (ntohs(ep->ether_type) <= ETHERMTU)
 104                           (void)printf(", 802.3");
 105                 else
 106                           (void)printf(", %s", tok2str(ethertype_values,"Unknown Ethertype (0x%04x)", ntohs(ep->ether_type)));
 107         }
 108
 109         (void)printf(", length %u: ", length);
 110 }
 111
 112 void
 113 ether_print(const u_char *p, u_int length, u_int caplen)
 114 {
 115         struct ether_header *ep;
 116         u_short ether_type;
 117         u_short extracted_ether_type;
 118
 119         if (caplen < ETHER_HDRLEN) {
 120                 printf("[|ether]");
 121                 return;
 122         }
 123
 124         if (eflag)
 125                 ether_hdr_print(p, length);
 126
 127         length -= ETHER_HDRLEN;
 128         caplen -= ETHER_HDRLEN;
 129         ep = (struct ether_header *)p;
 130         p += ETHER_HDRLEN;
 131
 132         ether_type = ntohs(ep->ether_type);
 133
 134         /*
 135          * Is it (gag) an 802.3 encapsulation?
 136          */
 137         if (ether_type <= ETHERMTU) {
 138                 /* Try to print the LLC-layer header & higher layers */
 139                 if (llc_print(p, length, caplen, ESRC(ep), EDST(ep),
 140                     &extracted_ether_type) == 0) {
 141                         /* ether_type not known, print raw packet */
 142                         if (!eflag)
 143                                 ether_hdr_print((u_char *)ep, length + ETHER_HDRLEN);
 144
 145                         if (!suppress_default_print)
 146                                 default_print(p, caplen);
 147                 }
 148         } else if (ether_encap_print(ether_type, p, length, caplen,
 149             &extracted_ether_type) == 0) {
 150                 /* ether_type not known, print raw packet */
 151                 if (!eflag)
 152                         ether_hdr_print((u_char *)ep, length + ETHER_HDRLEN);
 153
 154                 if (!suppress_default_print)
 155                         default_print(p, caplen);
 156         }
 157 }
 158
 159 /*
 160  * This is the top level routine of the printer.  'p' points
 161  * to the ether header of the packet, 'h->ts' is the timestamp,
 162  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
 163  * is the number of bytes actually captured.
 164  */
 165 u_int
 166 ether_if_print(const struct pcap_pkthdr *h, const u_char *p)
 167 {
 168         ether_print(p, h->len, h->caplen);
 169
 170         return (ETHER_HDRLEN);
 171 }
 172
 173 /*
 174  * Prints the packet encapsulated in an Ethernet data segment
 175  * (or an equivalent encapsulation), given the Ethernet type code.
 176  *
 177  * Returns non-zero if it can do so, zero if the ethertype is unknown.
 178  *
 179  * The Ethernet type code is passed through a pointer; if it was
 180  * ETHERTYPE_8021Q, it gets updated to be the Ethernet type of
 181  * the 802.1Q payload, for the benefit of lower layers that might
 182  * want to know what it is.
 183  */
 184
 185 int
 186 ether_encap_print(u_short ether_type, const u_char *p,
 187     u_int length, u_int caplen, u_short *extracted_ether_type)
 188 {
 189  recurse:
 190         *extracted_ether_type = ether_type;
 191
 192         switch (ether_type) {
 193
 194         case ETHERTYPE_IP:
 195                 ip_print(gndo, p, length);
 196                 return (1);
 197
 198 #ifdef INET6
 199         case ETHERTYPE_IPV6:
 200                 ip6_print(p, length);
 201                 return (1);
 202 #endif /*INET6*/
 203
 204         case ETHERTYPE_ARP:
 205         case ETHERTYPE_REVARP:
 206                 arp_print(gndo, p, length, caplen);
 207                 return (1);
 208
 209         case ETHERTYPE_DN:
 210                 decnet_print(p, length, caplen);
 211                 return (1);
 212
 213         case ETHERTYPE_ATALK:
 214                 if (vflag)
 215                         fputs("et1 ", stdout);
 216                 atalk_print(p, length);
 217                 return (1);
 218
 219         case ETHERTYPE_AARP:
 220                 aarp_print(p, length);
 221                 return (1);
 222
 223         case ETHERTYPE_IPX:
 224                 printf("(NOV-ETHII) ");
 225                 ipx_print(p, length);
 226                 return (1);
 227
 228         case ETHERTYPE_8021Q:
 229                 if (eflag)
 230                     printf("vlan %u, p %u%s, ",
 231                            ntohs(*(u_int16_t *)p) & 0xfff,
 232                            ntohs(*(u_int16_t *)p) >> 13,
 233                            (ntohs(*(u_int16_t *)p) & 0x1000) ? ", CFI" : "");
 234
 235                 ether_type = ntohs(*(u_int16_t *)(p + 2));
 236                 p += 4;
 237                 length -= 4;
 238                 caplen -= 4;
 239
 240                 if (ether_type > ETHERMTU) {
 241                         if (eflag)
 242                                 printf("ethertype %s, ",
 243                                        tok2str(ethertype_values,"0x%04x", ether_type));
 244                         goto recurse;
 245                 }
 246
 247                 *extracted_ether_type = 0;
 248
 249                 if (llc_print(p, length, caplen, p - 18, p - 12,
 250                     extracted_ether_type) == 0) {
 251                         ether_hdr_print(p - 18, length + 4);
 252
 253                         if (!suppress_default_print) {
 254                                 default_print(p - 18, caplen + 4);
 255                         }
 256                 }
 257
 258
 259                 return (1);
 260
 261         case ETHERTYPE_JUMBO:
 262                 ether_type = ntohs(*(u_int16_t *)(p));
 263                 p += 2;
 264                 length -= 2;
 265                 caplen -= 2;
 266
 267                 if (ether_type > ETHERMTU) {
 268                     if (eflag)
 269                         printf("ethertype %s, ",
 270                                tok2str(ethertype_values,"0x%04x", ether_type));
 271                     goto recurse;
 272                 }
 273
 274                 *extracted_ether_type = 0;
 275
 276                 if (llc_print(p, length, caplen, p - 16, p - 10,
 277                               extracted_ether_type) == 0) {
 278                     ether_hdr_print(p - 16, length + 2);
 279
 280                     if (!suppress_default_print) {
 281                             default_print(p - 16, caplen + 2);
 282                     }
 283                 }
 284
 285                 return (1);
 286
 287         case ETHERTYPE_ISO:
 288                 isoclns_print(p+1, length-1, length-1);
 289                 return(1);
 290
 291         case ETHERTYPE_PPPOED:
 292         case ETHERTYPE_PPPOES:
 293         case ETHERTYPE_PPPOED2:
 294         case ETHERTYPE_PPPOES2:
 295                 pppoe_print(p, length);
 296                 return (1);
 297
 298         case ETHERTYPE_EAPOL:
 299                 eap_print(gndo, p, length);
 300                 return (1);
 301
 302         case ETHERTYPE_RRCP:
 303                 rrcp_print(gndo, p - 14 , length + 14);
 304                 return (1);
 305
 306         case ETHERTYPE_PPP:
 307                 if (length) {
 308                         printf(": ");
 309                         ppp_print(p, length);
 310                 }
 311                 return (1);
 312
 313         case ETHERTYPE_MPCP:
 314                 mpcp_print(p, length);
 315                 return (1);
 316
 317         case ETHERTYPE_SLOW:
 318                 slow_print(p, length);
 319                 return (1);
 320
 321         case ETHERTYPE_CFM:
 322         case ETHERTYPE_CFM_OLD:
 323                 cfm_print(p, length);
 324                 return (1);
 325
 326         case ETHERTYPE_LLDP:
 327                 lldp_print(p, length);
 328                 return (1);
 329
 330         case ETHERTYPE_LOOPBACK:
 331                 return (1);
 332
 333         case ETHERTYPE_MPLS:
 334         case ETHERTYPE_MPLS_MULTI:
 335                 mpls_print(p, length);
 336                 return (1);
 337
 338         case ETHERTYPE_LAT:
 339         case ETHERTYPE_SCA:
 340         case ETHERTYPE_MOPRC:
 341         case ETHERTYPE_MOPDL:
 342                 /* default_print for now */
 343         default:
 344                 return (0);
 345         }
 346 }
 347
 348
 349 /*
 350  * Local Variables:
 351  * c-style: whitesmith
 352  * c-basic-offset: 8
 353  * End:
 354  */
 355