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 1.103 2006-10-12 10:26:12 hannes 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_LANBRIDGE,      "Lanbridge" },
  60     { ETHERTYPE_DECDNS,         "DEC DNS" },
  61     { ETHERTYPE_DECDTS,         "DEC DTS" },
  62     { ETHERTYPE_VEXP,           "VEXP" },
  63     { ETHERTYPE_VPROD,          "VPROD" },
  64     { ETHERTYPE_ATALK,          "Appletalk" },
  65     { ETHERTYPE_AARP,           "Appletalk ARP" },
  66     { ETHERTYPE_IPX,            "IPX" },
  67     { ETHERTYPE_PPP,            "PPP" },
  68     { ETHERTYPE_MPCP,           "MPCP" },
  69     { ETHERTYPE_SLOW,           "Slow Protocols" },
  70     { ETHERTYPE_PPPOED,         "PPPoE D" },
  71     { ETHERTYPE_PPPOES,         "PPPoE S" },
  72     { ETHERTYPE_EAPOL,          "EAPOL" },
  73     { ETHERTYPE_JUMBO,          "Jumbo" },
  74     { ETHERTYPE_LOOPBACK,       "Loopback" },
  75     { ETHERTYPE_ISO,            "OSI" },
  76     { ETHERTYPE_GRE_ISO,        "GRE-OSI" },
  77     { ETHERTYPE_CFM,            "CFM" },
  78     { 0, NULL}
  79 };
  80
  81 static inline void
  82 ether_hdr_print(register const u_char *bp, u_int length)
  83 {
  84         register const struct ether_header *ep;
  85         ep = (const struct ether_header *)bp;
  86
  87         (void)printf("%s > %s",
  88                      etheraddr_string(ESRC(ep)),
  89                      etheraddr_string(EDST(ep)));
  90
  91         if (!qflag) {
  92                 if (ntohs(ep->ether_type) <= ETHERMTU)
  93                           (void)printf(", 802.3");
  94                 else
  95                           (void)printf(", ethertype %s (0x%04x)",
  96                                        tok2str(ethertype_values,"Unknown", ntohs(ep->ether_type)),
  97                                        ntohs(ep->ether_type));
  98         } else {
  99                 if (ntohs(ep->ether_type) <= ETHERMTU)
 100                           (void)printf(", 802.3");
 101                 else
 102                           (void)printf(", %s", tok2str(ethertype_values,"Unknown Ethertype (0x%04x)", ntohs(ep->ether_type)));
 103         }
 104
 105         (void)printf(", length %u: ", length);
 106 }
 107
 108 void
 109 ether_print(const u_char *p, u_int length, u_int caplen)
 110 {
 111         struct ether_header *ep;
 112         u_short ether_type;
 113         u_short extracted_ether_type;
 114
 115         if (caplen < ETHER_HDRLEN) {
 116                 printf("[|ether]");
 117                 return;
 118         }
 119
 120         if (eflag)
 121                 ether_hdr_print(p, length);
 122
 123         length -= ETHER_HDRLEN;
 124         caplen -= ETHER_HDRLEN;
 125         ep = (struct ether_header *)p;
 126         p += ETHER_HDRLEN;
 127
 128         ether_type = ntohs(ep->ether_type);
 129
 130         /*
 131          * Is it (gag) an 802.3 encapsulation?
 132          */
 133         if (ether_type <= ETHERMTU) {
 134                 /* Try to print the LLC-layer header & higher layers */
 135                 if (llc_print(p, length, caplen, ESRC(ep), EDST(ep),
 136                     &extracted_ether_type) == 0) {
 137                         /* ether_type not known, print raw packet */
 138                         if (!eflag)
 139                                 ether_hdr_print((u_char *)ep, length + ETHER_HDRLEN);
 140
 141                         if (!suppress_default_print)
 142                                 default_print(p, caplen);
 143                 }
 144         } else if (ether_encap_print(ether_type, p, length, caplen,
 145             &extracted_ether_type) == 0) {
 146                 /* ether_type not known, print raw packet */
 147                 if (!eflag)
 148                         ether_hdr_print((u_char *)ep, length + ETHER_HDRLEN);
 149
 150                 if (!suppress_default_print)
 151                         default_print(p, caplen);
 152         }
 153 }
 154
 155 /*
 156  * This is the top level routine of the printer.  'p' points
 157  * to the ether header of the packet, 'h->ts' is the timestamp,
 158  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
 159  * is the number of bytes actually captured.
 160  */
 161 u_int
 162 ether_if_print(const struct pcap_pkthdr *h, const u_char *p)
 163 {
 164         ether_print(p, h->len, h->caplen);
 165
 166         return (ETHER_HDRLEN);
 167 }
 168
 169 /*
 170  * Prints the packet encapsulated in an Ethernet data segment
 171  * (or an equivalent encapsulation), given the Ethernet type code.
 172  *
 173  * Returns non-zero if it can do so, zero if the ethertype is unknown.
 174  *
 175  * The Ethernet type code is passed through a pointer; if it was
 176  * ETHERTYPE_8021Q, it gets updated to be the Ethernet type of
 177  * the 802.1Q payload, for the benefit of lower layers that might
 178  * want to know what it is.
 179  */
 180
 181 int
 182 ether_encap_print(u_short ether_type, const u_char *p,
 183     u_int length, u_int caplen, u_short *extracted_ether_type)
 184 {
 185  recurse:
 186         *extracted_ether_type = ether_type;
 187
 188         switch (ether_type) {
 189
 190         case ETHERTYPE_IP:
 191                 ip_print(gndo, p, length);
 192                 return (1);
 193
 194 #ifdef INET6
 195         case ETHERTYPE_IPV6:
 196                 ip6_print(p, length);
 197                 return (1);
 198 #endif /*INET6*/
 199
 200         case ETHERTYPE_ARP:
 201         case ETHERTYPE_REVARP:
 202                 arp_print(gndo, p, length, caplen);
 203                 return (1);
 204
 205         case ETHERTYPE_DN:
 206                 decnet_print(p, length, caplen);
 207                 return (1);
 208
 209         case ETHERTYPE_ATALK:
 210                 if (vflag)
 211                         fputs("et1 ", stdout);
 212                 atalk_print(p, length);
 213                 return (1);
 214
 215         case ETHERTYPE_AARP:
 216                 aarp_print(p, length);
 217                 return (1);
 218
 219         case ETHERTYPE_IPX:
 220                 printf("(NOV-ETHII) ");
 221                 ipx_print(p, length);
 222                 return (1);
 223
 224         case ETHERTYPE_8021Q:
 225                 if (eflag)
 226                     printf("vlan %u, p %u%s, ",
 227                            ntohs(*(u_int16_t *)p) & 0xfff,
 228                            ntohs(*(u_int16_t *)p) >> 13,
 229                            (ntohs(*(u_int16_t *)p) & 0x1000) ? ", CFI" : "");
 230
 231                 ether_type = ntohs(*(u_int16_t *)(p + 2));
 232                 p += 4;
 233                 length -= 4;
 234                 caplen -= 4;
 235
 236                 if (ether_type > ETHERMTU) {
 237                         if (eflag)
 238                                 printf("ethertype %s, ",
 239                                        tok2str(ethertype_values,"0x%04x", ether_type));
 240                         goto recurse;
 241                 }
 242
 243                 *extracted_ether_type = 0;
 244
 245                 if (llc_print(p, length, caplen, p - 18, p - 12,
 246                     extracted_ether_type) == 0) {
 247                         ether_hdr_print(p - 18, length + 4);
 248
 249                         if (!suppress_default_print) {
 250                                 default_print(p - 18, caplen + 4);
 251                         }
 252                 }
 253
 254
 255                 return (1);
 256
 257         case ETHERTYPE_JUMBO:
 258                 ether_type = ntohs(*(u_int16_t *)(p));
 259                 p += 2;
 260                 length -= 2;
 261                 caplen -= 2;
 262
 263                 if (ether_type > ETHERMTU) {
 264                     if (eflag)
 265                         printf("ethertype %s, ",
 266                                tok2str(ethertype_values,"0x%04x", ether_type));
 267                     goto recurse;
 268                 }
 269
 270                 *extracted_ether_type = 0;
 271
 272                 if (llc_print(p, length, caplen, p - 16, p - 10,
 273                               extracted_ether_type) == 0) {
 274                     ether_hdr_print(p - 16, length + 2);
 275
 276                     if (!suppress_default_print) {
 277                             default_print(p - 16, caplen + 2);
 278                     }
 279                 }
 280
 281                 return (1);
 282
 283         case ETHERTYPE_ISO:
 284                 isoclns_print(p+1, length-1, length-1);
 285                 return(1);
 286
 287         case ETHERTYPE_PPPOED:
 288         case ETHERTYPE_PPPOES:
 289                 pppoe_print(p, length);
 290                 return (1);
 291
 292         case ETHERTYPE_EAPOL:
 293                 eap_print(gndo, p, length);
 294                 return (1);
 295
 296         case ETHERTYPE_PPP:
 297                 if (length) {
 298                         printf(": ");
 299                         ppp_print(p, length);
 300                 }
 301                 return (1);
 302
 303         case ETHERTYPE_MPCP:
 304                 mpcp_print(p, length);
 305                 return (1);
 306
 307         case ETHERTYPE_SLOW:
 308                 slow_print(p, length);
 309                 return (1);
 310
 311         case ETHERTYPE_CFM:
 312                 cfm_print(p, length);
 313                 return (1);
 314
 315         case ETHERTYPE_LOOPBACK:
 316                 return (1);
 317
 318         case ETHERTYPE_MPLS:
 319         case ETHERTYPE_MPLS_MULTI:
 320                 mpls_print(p, length);
 321                 return (1);
 322
 323         case ETHERTYPE_LAT:
 324         case ETHERTYPE_SCA:
 325         case ETHERTYPE_MOPRC:
 326         case ETHERTYPE_MOPDL:
 327                 /* default_print for now */
 328         default:
 329                 return (0);
 330         }
 331 }
 332
 333
 334 /*
 335  * Local Variables:
 336  * c-style: whitesmith
 337  * c-basic-offset: 8
 338  * End:
 339  */
 340