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 1.105 2007-08-03 11:03:19 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     { ETHERTYPE_LLDP,           "LLDP" },
  80     { 0, NULL}
  81 };
  82
  83 static inline void
  84 ether_hdr_print(register const u_char *bp, u_int length)
  85 {
  86         register const struct ether_header *ep;
  87         ep = (const struct ether_header *)bp;
  88
  89         (void)printf("%s > %s",
  90                      etheraddr_string(ESRC(ep)),
  91                      etheraddr_string(EDST(ep)));
  92
  93         if (!qflag) {
  94                 if (ntohs(ep->ether_type) <= ETHERMTU)
  95                           (void)printf(", 802.3");
  96                 else
  97                           (void)printf(", ethertype %s (0x%04x)",
  98                                        tok2str(ethertype_values,"Unknown", ntohs(ep->ether_type)),
  99                                        ntohs(ep->ether_type));
 100         } else {
 101                 if (ntohs(ep->ether_type) <= ETHERMTU)
 102                           (void)printf(", 802.3");
 103                 else
 104                           (void)printf(", %s", tok2str(ethertype_values,"Unknown Ethertype (0x%04x)", ntohs(ep->ether_type)));
 105         }
 106
 107         (void)printf(", length %u: ", length);
 108 }
 109
 110 void
 111 ether_print(const u_char *p, u_int length, u_int caplen)
 112 {
 113         struct ether_header *ep;
 114         u_short ether_type;
 115         u_short extracted_ether_type;
 116
 117         if (caplen < ETHER_HDRLEN) {
 118                 printf("[|ether]");
 119                 return;
 120         }
 121
 122         if (eflag)
 123                 ether_hdr_print(p, length);
 124
 125         length -= ETHER_HDRLEN;
 126         caplen -= ETHER_HDRLEN;
 127         ep = (struct ether_header *)p;
 128         p += ETHER_HDRLEN;
 129
 130         ether_type = ntohs(ep->ether_type);
 131
 132         /*
 133          * Is it (gag) an 802.3 encapsulation?
 134          */
 135         if (ether_type <= ETHERMTU) {
 136                 /* Try to print the LLC-layer header & higher layers */
 137                 if (llc_print(p, length, caplen, ESRC(ep), EDST(ep),
 138                     &extracted_ether_type) == 0) {
 139                         /* ether_type not known, print raw packet */
 140                         if (!eflag)
 141                                 ether_hdr_print((u_char *)ep, length + ETHER_HDRLEN);
 142
 143                         if (!suppress_default_print)
 144                                 default_print(p, caplen);
 145                 }
 146         } else if (ether_encap_print(ether_type, p, length, caplen,
 147             &extracted_ether_type) == 0) {
 148                 /* ether_type not known, print raw packet */
 149                 if (!eflag)
 150                         ether_hdr_print((u_char *)ep, length + ETHER_HDRLEN);
 151
 152                 if (!suppress_default_print)
 153                         default_print(p, caplen);
 154         }
 155 }
 156
 157 /*
 158  * This is the top level routine of the printer.  'p' points
 159  * to the ether header of the packet, 'h->ts' is the timestamp,
 160  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
 161  * is the number of bytes actually captured.
 162  */
 163 u_int
 164 ether_if_print(const struct pcap_pkthdr *h, const u_char *p)
 165 {
 166         ether_print(p, h->len, h->caplen);
 167
 168         return (ETHER_HDRLEN);
 169 }
 170
 171 /*
 172  * Prints the packet encapsulated in an Ethernet data segment
 173  * (or an equivalent encapsulation), given the Ethernet type code.
 174  *
 175  * Returns non-zero if it can do so, zero if the ethertype is unknown.
 176  *
 177  * The Ethernet type code is passed through a pointer; if it was
 178  * ETHERTYPE_8021Q, it gets updated to be the Ethernet type of
 179  * the 802.1Q payload, for the benefit of lower layers that might
 180  * want to know what it is.
 181  */
 182
 183 int
 184 ether_encap_print(u_short ether_type, const u_char *p,
 185     u_int length, u_int caplen, u_short *extracted_ether_type)
 186 {
 187  recurse:
 188         *extracted_ether_type = ether_type;
 189
 190         switch (ether_type) {
 191
 192         case ETHERTYPE_IP:
 193                 ip_print(gndo, p, length);
 194                 return (1);
 195
 196 #ifdef INET6
 197         case ETHERTYPE_IPV6:
 198                 ip6_print(p, length);
 199                 return (1);
 200 #endif /*INET6*/
 201
 202         case ETHERTYPE_ARP:
 203         case ETHERTYPE_REVARP:
 204                 arp_print(gndo, p, length, caplen);
 205                 return (1);
 206
 207         case ETHERTYPE_DN:
 208                 decnet_print(p, length, caplen);
 209                 return (1);
 210
 211         case ETHERTYPE_ATALK:
 212                 if (vflag)
 213                         fputs("et1 ", stdout);
 214                 atalk_print(p, length);
 215                 return (1);
 216
 217         case ETHERTYPE_AARP:
 218                 aarp_print(p, length);
 219                 return (1);
 220
 221         case ETHERTYPE_IPX:
 222                 printf("(NOV-ETHII) ");
 223                 ipx_print(p, length);
 224                 return (1);
 225
 226         case ETHERTYPE_8021Q:
 227                 if (eflag)
 228                     printf("vlan %u, p %u%s, ",
 229                            ntohs(*(u_int16_t *)p) & 0xfff,
 230                            ntohs(*(u_int16_t *)p) >> 13,
 231                            (ntohs(*(u_int16_t *)p) & 0x1000) ? ", CFI" : "");
 232
 233                 ether_type = ntohs(*(u_int16_t *)(p + 2));
 234                 p += 4;
 235                 length -= 4;
 236                 caplen -= 4;
 237
 238                 if (ether_type > ETHERMTU) {
 239                         if (eflag)
 240                                 printf("ethertype %s, ",
 241                                        tok2str(ethertype_values,"0x%04x", ether_type));
 242                         goto recurse;
 243                 }
 244
 245                 *extracted_ether_type = 0;
 246
 247                 if (llc_print(p, length, caplen, p - 18, p - 12,
 248                     extracted_ether_type) == 0) {
 249                         ether_hdr_print(p - 18, length + 4);
 250
 251                         if (!suppress_default_print) {
 252                                 default_print(p - 18, caplen + 4);
 253                         }
 254                 }
 255
 256
 257                 return (1);
 258
 259         case ETHERTYPE_JUMBO:
 260                 ether_type = ntohs(*(u_int16_t *)(p));
 261                 p += 2;
 262                 length -= 2;
 263                 caplen -= 2;
 264
 265                 if (ether_type > ETHERMTU) {
 266                     if (eflag)
 267                         printf("ethertype %s, ",
 268                                tok2str(ethertype_values,"0x%04x", ether_type));
 269                     goto recurse;
 270                 }
 271
 272                 *extracted_ether_type = 0;
 273
 274                 if (llc_print(p, length, caplen, p - 16, p - 10,
 275                               extracted_ether_type) == 0) {
 276                     ether_hdr_print(p - 16, length + 2);
 277
 278                     if (!suppress_default_print) {
 279                             default_print(p - 16, caplen + 2);
 280                     }
 281                 }
 282
 283                 return (1);
 284
 285         case ETHERTYPE_ISO:
 286                 isoclns_print(p+1, length-1, length-1);
 287                 return(1);
 288
 289         case ETHERTYPE_PPPOED:
 290         case ETHERTYPE_PPPOES:
 291                 pppoe_print(p, length);
 292                 return (1);
 293
 294         case ETHERTYPE_EAPOL:
 295                 eap_print(gndo, p, length);
 296                 return (1);
 297
 298         case ETHERTYPE_PPP:
 299                 if (length) {
 300                         printf(": ");
 301                         ppp_print(p, length);
 302                 }
 303                 return (1);
 304
 305         case ETHERTYPE_MPCP:
 306                 mpcp_print(p, length);
 307                 return (1);
 308
 309         case ETHERTYPE_SLOW:
 310                 slow_print(p, length);
 311                 return (1);
 312
 313         case ETHERTYPE_CFM:
 314         case ETHERTYPE_CFM_OLD:
 315                 cfm_print(p, length);
 316                 return (1);
 317
 318         case ETHERTYPE_LLDP:
 319                 lldp_print(p, length);
 320                 return (1);
 321
 322         case ETHERTYPE_LOOPBACK:
 323                 return (1);
 324
 325         case ETHERTYPE_MPLS:
 326         case ETHERTYPE_MPLS_MULTI:
 327                 mpls_print(p, length);
 328                 return (1);
 329
 330         case ETHERTYPE_LAT:
 331         case ETHERTYPE_SCA:
 332         case ETHERTYPE_MOPRC:
 333         case ETHERTYPE_MOPDL:
 334                 /* default_print for now */
 335         default:
 336                 return (0);
 337         }
 338 }
 339
 340
 341 /*
 342  * Local Variables:
 343  * c-style: whitesmith
 344  * c-basic-offset: 8
 345  * End:
 346  */
 347