contrib/tcpdump/print-llc.c

   1 /*
   2  * Copyright (c) 1992, 1993, 1994, 1995, 1996, 1997
   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  * Code by Matt Thomas, Digital Equipment Corporation
  22  *      with an awful lot of hacking by Jeffrey Mogul, DECWRL
  23  *
  24  * $FreeBSD$
  25  */
  26
  27 #ifndef lint
  28 static const char rcsid[] _U_ =
  29     "@(#) $Header: /tcpdump/master/tcpdump/print-llc.c,v 1.61.2.5 2005/09/29 07:40:13 hannes Exp $";
  30 #endif
  31
  32 #ifdef HAVE_CONFIG_H
  33 #include "config.h"
  34 #endif
  35
  36 #include <tcpdump-stdinc.h>
  37
  38 #include <stdio.h>
  39 #include <string.h>
  40
  41 #include "interface.h"
  42 #include "addrtoname.h"
  43 #include "extract.h"                    /* must come after interface.h */
  44
  45 #include "llc.h"
  46 #include "ethertype.h"
  47 #include "oui.h"
  48
  49 static struct tok llc_values[] = {
  50         { LLCSAP_NULL,     "Null" },
  51         { LLCSAP_GLOBAL,   "Global" },
  52         { LLCSAP_8021B_I,  "802.1B I" },
  53         { LLCSAP_8021B_G,  "802.1B G" },
  54         { LLCSAP_IP,       "IP" },
  55         { LLCSAP_SNA,      "SNA" },
  56         { LLCSAP_PROWAYNM, "ProWay NM" },
  57         { LLCSAP_8021D,    "STP" },
  58         { LLCSAP_RS511,    "RS511" },
  59         { LLCSAP_ISO8208,  "ISO8208" },
  60         { LLCSAP_PROWAY,   "ProWay" },
  61         { LLCSAP_SNAP,     "SNAP" },
  62         { LLCSAP_IPX,      "IPX" },
  63         { LLCSAP_NETBEUI,  "NetBeui" },
  64         { LLCSAP_ISONS,    "OSI" },
  65         { 0,               NULL },
  66 };
  67
  68 static struct tok llc_cmd_values[] = {
  69         { LLC_UI,       "ui" },
  70         { LLC_TEST,     "test" },
  71         { LLC_XID,      "xid" },
  72         { LLC_UA,       "ua" },
  73         { LLC_DISC,     "disc" },
  74         { LLC_DM,       "dm" },
  75         { LLC_SABME,    "sabme" },
  76         { LLC_FRMR,     "frmr" },
  77         { 0,            NULL }
  78 };
  79
  80 static const struct tok llc_flag_values[] = {
  81         { 0, "Command" },
  82         { LLC_GSAP, "Response" },
  83         { LLC_U_POLL, "Poll" },
  84         { LLC_GSAP|LLC_U_POLL, "Final" },
  85         { LLC_GSAP|LLC_IS_POLL, "Final" },
  86         { 0, NULL }
  87 };
  88
  89 static const struct tok llc_supervisory_values[] = {
  90         { 0, "Receiver Ready" },
  91         { 1, "Reject" },
  92         { 2, "Receiver not Ready" },
  93         { 0,             NULL }
  94 };
  95
  96
  97 static const struct tok cisco_values[] = {
  98         { PID_CISCO_CDP, "CDP" },
  99         { 0,             NULL }
 100 };
 101
 102 static const struct tok bridged_values[] = {
 103         { PID_RFC2684_ETH_FCS,     "Ethernet + FCS" },
 104         { PID_RFC2684_ETH_NOFCS,   "Ethernet w/o FCS" },
 105         { PID_RFC2684_802_4_FCS,   "802.4 + FCS" },
 106         { PID_RFC2684_802_4_NOFCS, "802.4 w/o FCS" },
 107         { PID_RFC2684_802_5_FCS,   "Token Ring + FCS" },
 108         { PID_RFC2684_802_5_NOFCS, "Token Ring w/o FCS" },
 109         { PID_RFC2684_FDDI_FCS,    "FDDI + FCS" },
 110         { PID_RFC2684_FDDI_NOFCS,  "FDDI w/o FCS" },
 111         { PID_RFC2684_802_6_FCS,   "802.6 + FCS" },
 112         { PID_RFC2684_802_6_NOFCS, "802.6 w/o FCS" },
 113         { PID_RFC2684_BPDU,        "BPDU" },
 114         { 0,                       NULL },
 115 };
 116
 117 struct oui_tok {
 118         u_int32_t       oui;
 119         const struct tok *tok;
 120 };
 121
 122 static const struct oui_tok oui_to_tok[] = {
 123         { OUI_ENCAP_ETHER, ethertype_values },
 124         { OUI_CISCO_90, ethertype_values },     /* uses some Ethertype values */
 125         { OUI_APPLETALK, ethertype_values },    /* uses some Ethertype values */
 126         { OUI_CISCO, cisco_values },
 127         { OUI_RFC2684, bridged_values },        /* bridged, RFC 2427 FR or RFC 2864 ATM */
 128         { 0, NULL }
 129 };
 130
 131 /*
 132  * Returns non-zero IFF it succeeds in printing the header
 133  */
 134 int
 135 llc_print(const u_char *p, u_int length, u_int caplen,
 136           const u_char *esrc, const u_char *edst, u_short *extracted_ethertype)
 137 {
 138         u_int8_t dsap_field, dsap, ssap_field, ssap;
 139         u_int16_t control;
 140         int is_u;
 141         register int ret;
 142
 143         if (caplen < 3) {
 144                 (void)printf("[|llc]");
 145                 default_print((u_char *)p, caplen);
 146                 return(0);
 147         }
 148
 149         dsap_field = *p;
 150         dsap = dsap_field & ~LLC_IG;
 151         ssap_field = *(p + 1);
 152         ssap = ssap_field & ~LLC_GSAP;
 153
 154         /*
 155          * OK, what type of LLC frame is this?  The length
 156          * of the control field depends on that - I frames
 157          * have a two-byte control field, and U frames have
 158          * a one-byte control field.
 159          */
 160         control = *(p + 2);
 161         if ((control & LLC_U_FMT) == LLC_U_FMT) {
 162                 /*
 163                  * U frame.
 164                  */
 165                 is_u = 1;
 166         } else {
 167                 /*
 168                  * The control field in I and S frames is
 169                  * 2 bytes...
 170                  */
 171                 if (caplen < 4) {
 172                         (void)printf("[|llc]");
 173                         default_print((u_char *)p, caplen);
 174                         return(0);
 175                 }
 176
 177                 /*
 178                  * ...and is little-endian.
 179                  */
 180                 control = EXTRACT_LE_16BITS(p + 2);
 181                 is_u = 0;
 182         }
 183
 184         if (ssap == LLCSAP_GLOBAL && dsap == LLCSAP_GLOBAL) {
 185                 /*
 186                  * This is an Ethernet_802.3 IPX frame; it has an
 187                  * 802.3 header (i.e., an Ethernet header where the
 188                  * type/length field is <= ETHERMTU, i.e. it's a length
 189                  * field, not a type field), but has no 802.2 header -
 190                  * the IPX packet starts right after the Ethernet header,
 191                  * with a signature of two bytes of 0xFF (which is
 192                  * LLCSAP_GLOBAL).
 193                  *
 194                  * (It might also have been an Ethernet_802.3 IPX at
 195                  * one time, but got bridged onto another network,
 196                  * such as an 802.11 network; this has appeared in at
 197                  * least one capture file.)
 198                  */
 199
 200             if (eflag)
 201                 printf("IPX 802.3: ");
 202
 203             ipx_print(p, length);
 204             return (1);
 205         }
 206
 207         if (eflag) {
 208                 printf("LLC, dsap %s (0x%02x), ssap %s (0x%02x)",
 209                        tok2str(llc_values, "Unknown", dsap),
 210                        dsap,
 211                        tok2str(llc_values, "Unknown", ssap),
 212                        ssap);
 213
 214                 if (is_u) {
 215                         printf(", cmd 0x%02x: ", control);
 216                 } else {
 217                         printf(", cmd 0x%04x: ", control);
 218                 }
 219         }
 220
 221         if (ssap == LLCSAP_8021D && dsap == LLCSAP_8021D &&
 222             control == LLC_UI) {
 223                 stp_print(p+3, length-3);
 224                 return (1);
 225         }
 226
 227         if (ssap == LLCSAP_IP && dsap == LLCSAP_IP &&
 228             control == LLC_UI) {
 229                 ip_print(gndo, p+4, length-4);
 230                 return (1);
 231         }
 232
 233         if (ssap == LLCSAP_IPX && dsap == LLCSAP_IPX &&
 234             control == LLC_UI) {
 235                 /*
 236                  * This is an Ethernet_802.2 IPX frame, with an 802.3
 237                  * header and an 802.2 LLC header with the source and
 238                  * destination SAPs being the IPX SAP.
 239                  *
 240                  * Skip DSAP, LSAP, and control field.
 241                  */
 242                 if (eflag)
 243                         printf("IPX 802.2: ");
 244
 245                 ipx_print(p+3, length-3);
 246                 return (1);
 247         }
 248
 249 #ifdef TCPDUMP_DO_SMB
 250         if (ssap == LLCSAP_NETBEUI && dsap == LLCSAP_NETBEUI
 251             && (!(control & LLC_S_FMT) || control == LLC_U_FMT)) {
 252                 /*
 253                  * we don't actually have a full netbeui parser yet, but the
 254                  * smb parser can handle many smb-in-netbeui packets, which
 255                  * is very useful, so we call that
 256                  *
 257                  * We don't call it for S frames, however, just I frames
 258                  * (which are frames that don't have the low-order bit,
 259                  * LLC_S_FMT, set in the first byte of the control field)
 260                  * and UI frames (whose control field is just 3, LLC_U_FMT).
 261                  */
 262
 263                 /*
 264                  * Skip the LLC header.
 265                  */
 266                 if (is_u) {
 267                         p += 3;
 268                         length -= 3;
 269                         caplen -= 3;
 270                 } else {
 271                         p += 4;
 272                         length -= 4;
 273                         caplen -= 4;
 274                 }
 275                 netbeui_print(control, p, length);
 276                 return (1);
 277         }
 278 #endif
 279         if (ssap == LLCSAP_ISONS && dsap == LLCSAP_ISONS
 280             && control == LLC_UI) {
 281                 isoclns_print(p + 3, length - 3, caplen - 3);
 282                 return (1);
 283         }
 284
 285         if (ssap == LLCSAP_SNAP && dsap == LLCSAP_SNAP
 286             && control == LLC_UI) {
 287                 /*
 288                  * XXX - what *is* the right bridge pad value here?
 289                  * Does anybody ever bridge one form of LAN traffic
 290                  * over a networking type that uses 802.2 LLC?
 291                  */
 292                 ret = snap_print(p+3, length-3, caplen-3, extracted_ethertype,
 293                     2);
 294                 if (ret)
 295                         return (ret);
 296         }
 297
 298         if (!eflag) {
 299                 if (ssap == dsap) {
 300                         if (esrc == NULL || edst == NULL)
 301                                 (void)printf("%s ", tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
 302                         else
 303                                 (void)printf("%s > %s %s ",
 304                                                 etheraddr_string(esrc),
 305                                                 etheraddr_string(edst),
 306                                                 tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
 307                 } else {
 308                         if (esrc == NULL || edst == NULL)
 309                                 (void)printf("%s > %s ",
 310                                         tok2str(llc_values, "Unknown SSAP 0x%02x", ssap),
 311                                         tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
 312                         else
 313                                 (void)printf("%s %s > %s %s ",
 314                                         etheraddr_string(esrc),
 315                                         tok2str(llc_values, "Unknown SSAP 0x%02x", ssap),
 316                                         etheraddr_string(edst),
 317                                         tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
 318                 }
 319         }
 320
 321         if (is_u) {
 322                 printf("Unnumbered, %s, Flags [%s], length %u",
 323                        tok2str(llc_cmd_values, "%02x", LLC_U_CMD(control)),
 324                        bittok2str(llc_flag_values,"?",(ssap) | (control & LLC_U_POLL)),
 325                        length);
 326
 327                 p += 3;
 328                 length -= 3;
 329                 caplen -= 3;
 330
 331                 if ((control & ~LLC_U_POLL) == LLC_XID) {
 332                         if (*p == LLC_XID_FI) {
 333                                 printf(": %02x %02x", p[1], p[2]);
 334                                 p += 3;
 335                                 length -= 3;
 336                                 caplen -= 3;
 337                         }
 338                 }
 339         } else {
 340
 341                 if ((control & LLC_S_FMT) == LLC_S_FMT) {
 342                         (void)printf("Supervisory, %s, rcv seq %u, Flags [%s], length %u",
 343                                 tok2str(llc_supervisory_values,"?",LLC_S_CMD(control)),
 344                                 LLC_IS_NR(control),
 345                                 bittok2str(llc_flag_values,"?",(ssap) | (control & LLC_IS_POLL)),
 346                                 length);
 347                 } else {
 348                         (void)printf("Information, send seq %u, rcv seq %u, Flags [%s], length %u",
 349                                 LLC_I_NS(control),
 350                                 LLC_IS_NR(control),
 351                                 bittok2str(llc_flag_values,"?",(ssap) | (control & LLC_IS_POLL)),
 352                                 length);
 353                 }
 354                 p += 4;
 355                 length -= 4;
 356                 caplen -= 4;
 357         }
 358         return(1);
 359 }
 360
 361 int
 362 snap_print(const u_char *p, u_int length, u_int caplen,
 363     u_short *extracted_ethertype, u_int bridge_pad)
 364 {
 365         u_int32_t orgcode;
 366         register u_short et;
 367         register int ret;
 368
 369         TCHECK2(*p, 5);
 370         orgcode = EXTRACT_24BITS(p);
 371         et = EXTRACT_16BITS(p + 3);
 372
 373         if (eflag) {
 374                 const struct tok *tok = NULL;
 375                 const struct oui_tok *otp;
 376
 377                 for (otp = &oui_to_tok[0]; otp->tok != NULL; otp++) {
 378                         if (otp->oui == orgcode) {
 379                                 tok = otp->tok;
 380                                 break;
 381                         }
 382                 }
 383                 (void)printf("oui %s (0x%06x), %s %s (0x%04x): ",
 384                      tok2str(oui_values, "Unknown", orgcode),
 385                      orgcode,
 386                      (orgcode == 0x000000 ? "ethertype" : "pid"),
 387                      tok2str(tok, "Unknown", et),
 388                      et);
 389         }
 390         p += 5;
 391         length -= 5;
 392         caplen -= 5;
 393
 394         switch (orgcode) {
 395         case OUI_ENCAP_ETHER:
 396         case OUI_CISCO_90:
 397                 /*
 398                  * This is an encapsulated Ethernet packet,
 399                  * or a packet bridged by some piece of
 400                  * Cisco hardware; the protocol ID is
 401                  * an Ethernet protocol type.
 402                  */
 403                 ret = ether_encap_print(et, p, length, caplen,
 404                     extracted_ethertype);
 405                 if (ret)
 406                         return (ret);
 407                 break;
 408
 409         case OUI_APPLETALK:
 410                 if (et == ETHERTYPE_ATALK) {
 411                         /*
 412                          * No, I have no idea why Apple used one
 413                          * of their own OUIs, rather than
 414                          * 0x000000, and an Ethernet packet
 415                          * type, for Appletalk data packets,
 416                          * but used 0x000000 and an Ethernet
 417                          * packet type for AARP packets.
 418                          */
 419                         ret = ether_encap_print(et, p, length, caplen,
 420                             extracted_ethertype);
 421                         if (ret)
 422                                 return (ret);
 423                 }
 424                 break;
 425
 426         case OUI_CISCO:
 427                 if (et == PID_CISCO_CDP) {
 428                         cdp_print(p, length, caplen);
 429                         return (1);
 430                 }
 431                 break;
 432
 433         case OUI_RFC2684:
 434                 switch (et) {
 435
 436                 case PID_RFC2684_ETH_FCS:
 437                 case PID_RFC2684_ETH_NOFCS:
 438                         /*
 439                          * XXX - remove the last two bytes for
 440                          * PID_RFC2684_ETH_FCS?
 441                          */
 442                         /*
 443                          * Skip the padding.
 444                          */
 445                         TCHECK2(*p, bridge_pad);
 446                         caplen -= bridge_pad;
 447                         length -= bridge_pad;
 448                         p += bridge_pad;
 449
 450                         /*
 451                          * What remains is an Ethernet packet.
 452                          */
 453                         ether_print(p, length, caplen);
 454                         return (1);
 455
 456                 case PID_RFC2684_802_5_FCS:
 457                 case PID_RFC2684_802_5_NOFCS:
 458                         /*
 459                          * XXX - remove the last two bytes for
 460                          * PID_RFC2684_ETH_FCS?
 461                          */
 462                         /*
 463                          * Skip the padding, but not the Access
 464                          * Control field.
 465                          */
 466                         TCHECK2(*p, bridge_pad);
 467                         caplen -= bridge_pad;
 468                         length -= bridge_pad;
 469                         p += bridge_pad;
 470
 471                         /*
 472                          * What remains is an 802.5 Token Ring
 473                          * packet.
 474                          */
 475                         token_print(p, length, caplen);
 476                         return (1);
 477
 478                 case PID_RFC2684_FDDI_FCS:
 479                 case PID_RFC2684_FDDI_NOFCS:
 480                         /*
 481                          * XXX - remove the last two bytes for
 482                          * PID_RFC2684_ETH_FCS?
 483                          */
 484                         /*
 485                          * Skip the padding.
 486                          */
 487                         TCHECK2(*p, bridge_pad + 1);
 488                         caplen -= bridge_pad + 1;
 489                         length -= bridge_pad + 1;
 490                         p += bridge_pad + 1;
 491
 492                         /*
 493                          * What remains is an FDDI packet.
 494                          */
 495                         fddi_print(p, length, caplen);
 496                         return (1);
 497
 498                 case PID_RFC2684_BPDU:
 499                         stp_print(p, length);
 500                         return (1);
 501                 }
 502         }
 503         return (0);
 504
 505 trunc:
 506         (void)printf("[|snap]");
 507         return (1);
 508 }
 509
 510
 511 /*
 512  * Local Variables:
 513  * c-style: whitesmith
 514  * c-basic-offset: 8
 515  * End:
 516  */