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 1.104 2007-07-23 09:01:09 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_OLD,        "CFM (old)" },
  78     { ETHERTYPE_CFM,            "CFM" },
  79     { 0, NULL}
  80 };
  81
  82 static inline void
  83 ether_hdr_print(register const u_char *bp, u_int length)
  84 {
  85         register const struct ether_header *ep;
  86         ep = (const struct ether_header *)bp;
  87
  88         (void)printf("%s > %s",
  89                      etheraddr_string(ESRC(ep)),
  90                      etheraddr_string(EDST(ep)));
  91
  92         if (!qflag) {
  93                 if (ntohs(ep->ether_type) <= ETHERMTU)
  94                           (void)printf(", 802.3");
  95                 else
  96                           (void)printf(", ethertype %s (0x%04x)",
  97                                        tok2str(ethertype_values,"Unknown", ntohs(ep->ether_type)),
  98                                        ntohs(ep->ether_type));
  99         } else {
 100                 if (ntohs(ep->ether_type) <= ETHERMTU)
 101                           (void)printf(", 802.3");
 102                 else
 103                           (void)printf(", %s", tok2str(ethertype_values,"Unknown Ethertype (0x%04x)", ntohs(ep->ether_type)));
 104         }
 105
 106         (void)printf(", length %u: ", length);
 107 }
 108
 109 void
 110 ether_print(const u_char *p, u_int length, u_int caplen)
 111 {
 112         struct ether_header *ep;
 113         u_short ether_type;
 114         u_short extracted_ether_type;
 115
 116         if (caplen < ETHER_HDRLEN) {
 117                 printf("[|ether]");
 118                 return;
 119         }
 120
 121         if (eflag)
 122                 ether_hdr_print(p, length);
 123
 124         length -= ETHER_HDRLEN;
 125         caplen -= ETHER_HDRLEN;
 126         ep = (struct ether_header *)p;
 127         p += ETHER_HDRLEN;
 128
 129         ether_type = ntohs(ep->ether_type);
 130
 131         /*
 132          * Is it (gag) an 802.3 encapsulation?
 133          */
 134         if (ether_type <= ETHERMTU) {
 135                 /* Try to print the LLC-layer header & higher layers */
 136                 if (llc_print(p, length, caplen, ESRC(ep), EDST(ep),
 137                     &extracted_ether_type) == 0) {
 138                         /* ether_type not known, print raw packet */
 139                         if (!eflag)
 140                                 ether_hdr_print((u_char *)ep, length + ETHER_HDRLEN);
 141
 142                         if (!suppress_default_print)
 143                                 default_print(p, caplen);
 144                 }
 145         } else if (ether_encap_print(ether_type, p, length, caplen,
 146             &extracted_ether_type) == 0) {
 147                 /* ether_type not known, print raw packet */
 148                 if (!eflag)
 149                         ether_hdr_print((u_char *)ep, length + ETHER_HDRLEN);
 150
 151                 if (!suppress_default_print)
 152                         default_print(p, caplen);
 153         }
 154 }
 155
 156 /*
 157  * This is the top level routine of the printer.  'p' points
 158  * to the ether header of the packet, 'h->ts' is the timestamp,
 159  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
 160  * is the number of bytes actually captured.
 161  */
 162 u_int
 163 ether_if_print(const struct pcap_pkthdr *h, const u_char *p)
 164 {
 165         ether_print(p, h->len, h->caplen);
 166
 167         return (ETHER_HDRLEN);
 168 }
 169
 170 /*
 171  * Prints the packet encapsulated in an Ethernet data segment
 172  * (or an equivalent encapsulation), given the Ethernet type code.
 173  *
 174  * Returns non-zero if it can do so, zero if the ethertype is unknown.
 175  *
 176  * The Ethernet type code is passed through a pointer; if it was
 177  * ETHERTYPE_8021Q, it gets updated to be the Ethernet type of
 178  * the 802.1Q payload, for the benefit of lower layers that might
 179  * want to know what it is.
 180  */
 181
 182 int
 183 ether_encap_print(u_short ether_type, const u_char *p,
 184     u_int length, u_int caplen, u_short *extracted_ether_type)
 185 {
 186  recurse:
 187         *extracted_ether_type = ether_type;
 188
 189         switch (ether_type) {
 190
 191         case ETHERTYPE_IP:
 192                 ip_print(gndo, p, length);
 193                 return (1);
 194
 195 #ifdef INET6
 196         case ETHERTYPE_IPV6:
 197                 ip6_print(p, length);
 198                 return (1);
 199 #endif /*INET6*/
 200
 201         case ETHERTYPE_ARP:
 202         case ETHERTYPE_REVARP:
 203                 arp_print(gndo, p, length, caplen);
 204                 return (1);
 205
 206         case ETHERTYPE_DN:
 207                 decnet_print(p, length, caplen);
 208                 return (1);
 209
 210         case ETHERTYPE_ATALK:
 211                 if (vflag)
 212                         fputs("et1 ", stdout);
 213                 atalk_print(p, length);
 214                 return (1);
 215
 216         case ETHERTYPE_AARP:
 217                 aarp_print(p, length);
 218                 return (1);
 219
 220         case ETHERTYPE_IPX:
 221                 printf("(NOV-ETHII) ");
 222                 ipx_print(p, length);
 223                 return (1);
 224
 225         case ETHERTYPE_8021Q:
 226                 if (eflag)
 227                     printf("vlan %u, p %u%s, ",
 228                            ntohs(*(u_int16_t *)p) & 0xfff,
 229                            ntohs(*(u_int16_t *)p) >> 13,
 230                            (ntohs(*(u_int16_t *)p) & 0x1000) ? ", CFI" : "");
 231
 232                 ether_type = ntohs(*(u_int16_t *)(p + 2));
 233                 p += 4;
 234                 length -= 4;
 235                 caplen -= 4;
 236
 237                 if (ether_type > ETHERMTU) {
 238                         if (eflag)
 239                                 printf("ethertype %s, ",
 240                                        tok2str(ethertype_values,"0x%04x", ether_type));
 241                         goto recurse;
 242                 }
 243
 244                 *extracted_ether_type = 0;
 245
 246                 if (llc_print(p, length, caplen, p - 18, p - 12,
 247                     extracted_ether_type) == 0) {
 248                         ether_hdr_print(p - 18, length + 4);
 249
 250                         if (!suppress_default_print) {
 251                                 default_print(p - 18, caplen + 4);
 252                         }
 253                 }
 254
 255
 256                 return (1);
 257
 258         case ETHERTYPE_JUMBO:
 259                 ether_type = ntohs(*(u_int16_t *)(p));
 260                 p += 2;
 261                 length -= 2;
 262                 caplen -= 2;
 263
 264                 if (ether_type > ETHERMTU) {
 265                     if (eflag)
 266                         printf("ethertype %s, ",
 267                                tok2str(ethertype_values,"0x%04x", ether_type));
 268                     goto recurse;
 269                 }
 270
 271                 *extracted_ether_type = 0;
 272
 273                 if (llc_print(p, length, caplen, p - 16, p - 10,
 274                               extracted_ether_type) == 0) {
 275                     ether_hdr_print(p - 16, length + 2);
 276
 277                     if (!suppress_default_print) {
 278                             default_print(p - 16, caplen + 2);
 279                     }
 280                 }
 281
 282                 return (1);
 283
 284         case ETHERTYPE_ISO:
 285                 isoclns_print(p+1, length-1, length-1);
 286                 return(1);
 287
 288         case ETHERTYPE_PPPOED:
 289         case ETHERTYPE_PPPOES:
 290                 pppoe_print(p, length);
 291                 return (1);
 292
 293         case ETHERTYPE_EAPOL:
 294                 eap_print(gndo, p, length);
 295                 return (1);
 296
 297         case ETHERTYPE_PPP:
 298                 if (length) {
 299                         printf(": ");
 300                         ppp_print(p, length);
 301                 }
 302                 return (1);
 303
 304         case ETHERTYPE_MPCP:
 305                 mpcp_print(p, length);
 306                 return (1);
 307
 308         case ETHERTYPE_SLOW:
 309                 slow_print(p, length);
 310                 return (1);
 311
 312         case ETHERTYPE_CFM:
 313         case ETHERTYPE_CFM_OLD:
 314                 cfm_print(p, length);
 315                 return (1);
 316
 317         case ETHERTYPE_LOOPBACK:
 318                 return (1);
 319
 320         case ETHERTYPE_MPLS:
 321         case ETHERTYPE_MPLS_MULTI:
 322                 mpls_print(p, length);
 323                 return (1);
 324
 325         case ETHERTYPE_LAT:
 326         case ETHERTYPE_SCA:
 327         case ETHERTYPE_MOPRC:
 328         case ETHERTYPE_MOPDL:
 329                 /* default_print for now */
 330         default:
 331                 return (0);
 332         }
 333 }
 334
 335
 336 /*
 337  * Local Variables:
 338  * c-style: whitesmith
 339  * c-basic-offset: 8
 340  * End:
 341  */
 342