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 1.75 2007-04-13 09:43:11 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_IS_POLL, "Poll" },
  86         { LLC_GSAP|LLC_IS_POLL, "Final" },
  87         { 0, NULL }
  88 };
  89
  90
  91 static const struct tok llc_ig_flag_values[] = {
  92         { 0, "Individual" },
  93         { LLC_IG, "Group" },
  94         { 0, NULL }
  95 };
  96
  97
  98 static const struct tok llc_supervisory_values[] = {
  99         { 0, "Receiver Ready" },
 100         { 1, "Receiver not Ready" },
 101         { 2, "Reject" },
 102         { 0,             NULL }
 103 };
 104
 105
 106 static const struct tok cisco_values[] = {
 107         { PID_CISCO_CDP, "CDP" },
 108         { PID_CISCO_VTP, "VTP" },
 109         { PID_CISCO_DTP, "DTP" },
 110         { PID_CISCO_UDLD, "UDLD" },
 111         { PID_CISCO_PVST, "PVST" },
 112         { 0,             NULL }
 113 };
 114
 115 static const struct tok bridged_values[] = {
 116         { PID_RFC2684_ETH_FCS,     "Ethernet + FCS" },
 117         { PID_RFC2684_ETH_NOFCS,   "Ethernet w/o FCS" },
 118         { PID_RFC2684_802_4_FCS,   "802.4 + FCS" },
 119         { PID_RFC2684_802_4_NOFCS, "802.4 w/o FCS" },
 120         { PID_RFC2684_802_5_FCS,   "Token Ring + FCS" },
 121         { PID_RFC2684_802_5_NOFCS, "Token Ring w/o FCS" },
 122         { PID_RFC2684_FDDI_FCS,    "FDDI + FCS" },
 123         { PID_RFC2684_FDDI_NOFCS,  "FDDI w/o FCS" },
 124         { PID_RFC2684_802_6_FCS,   "802.6 + FCS" },
 125         { PID_RFC2684_802_6_NOFCS, "802.6 w/o FCS" },
 126         { PID_RFC2684_BPDU,        "BPDU" },
 127         { 0,                       NULL },
 128 };
 129
 130 static const struct tok null_values[] = {
 131         { 0,             NULL }
 132 };
 133
 134 struct oui_tok {
 135         u_int32_t       oui;
 136         const struct tok *tok;
 137 };
 138
 139 static const struct oui_tok oui_to_tok[] = {
 140         { OUI_ENCAP_ETHER, ethertype_values },
 141         { OUI_CISCO_90, ethertype_values },     /* uses some Ethertype values */
 142         { OUI_APPLETALK, ethertype_values },    /* uses some Ethertype values */
 143         { OUI_CISCO, cisco_values },
 144         { OUI_RFC2684, bridged_values },        /* bridged, RFC 2427 FR or RFC 2864 ATM */
 145         { 0, NULL }
 146 };
 147
 148 /*
 149  * Returns non-zero IFF it succeeds in printing the header
 150  */
 151 int
 152 llc_print(const u_char *p, u_int length, u_int caplen,
 153           const u_char *esrc, const u_char *edst, u_short *extracted_ethertype)
 154 {
 155         u_int8_t dsap_field, dsap, ssap_field, ssap;
 156         u_int16_t control;
 157         int is_u;
 158         register int ret;
 159
 160         *extracted_ethertype = 0;
 161
 162         if (caplen < 3) {
 163                 (void)printf("[|llc]");
 164                 default_print((u_char *)p, caplen);
 165                 return(0);
 166         }
 167
 168         dsap_field = *p;
 169         ssap_field = *(p + 1);
 170
 171         /*
 172          * OK, what type of LLC frame is this?  The length
 173          * of the control field depends on that - I frames
 174          * have a two-byte control field, and U frames have
 175          * a one-byte control field.
 176          */
 177         control = *(p + 2);
 178         if ((control & LLC_U_FMT) == LLC_U_FMT) {
 179                 /*
 180                  * U frame.
 181                  */
 182                 is_u = 1;
 183         } else {
 184                 /*
 185                  * The control field in I and S frames is
 186                  * 2 bytes...
 187                  */
 188                 if (caplen < 4) {
 189                         (void)printf("[|llc]");
 190                         default_print((u_char *)p, caplen);
 191                         return(0);
 192                 }
 193
 194                 /*
 195                  * ...and is little-endian.
 196                  */
 197                 control = EXTRACT_LE_16BITS(p + 2);
 198                 is_u = 0;
 199         }
 200
 201         if (ssap_field == LLCSAP_GLOBAL && dsap_field == LLCSAP_GLOBAL) {
 202                 /*
 203                  * This is an Ethernet_802.3 IPX frame; it has an
 204                  * 802.3 header (i.e., an Ethernet header where the
 205                  * type/length field is <= ETHERMTU, i.e. it's a length
 206                  * field, not a type field), but has no 802.2 header -
 207                  * the IPX packet starts right after the Ethernet header,
 208                  * with a signature of two bytes of 0xFF (which is
 209                  * LLCSAP_GLOBAL).
 210                  *
 211                  * (It might also have been an Ethernet_802.3 IPX at
 212                  * one time, but got bridged onto another network,
 213                  * such as an 802.11 network; this has appeared in at
 214                  * least one capture file.)
 215                  */
 216
 217             if (eflag)
 218                 printf("IPX 802.3: ");
 219
 220             ipx_print(p, length);
 221             return (1);
 222         }
 223
 224         dsap = dsap_field & ~LLC_IG;
 225         ssap = ssap_field & ~LLC_GSAP;
 226
 227         if (eflag) {
 228                 printf("LLC, dsap %s (0x%02x) %s, ssap %s (0x%02x) %s",
 229                        tok2str(llc_values, "Unknown", dsap),
 230                        dsap,
 231                        tok2str(llc_ig_flag_values, "Unknown", dsap_field & LLC_IG),
 232                        tok2str(llc_values, "Unknown", ssap),
 233                        ssap,
 234                        tok2str(llc_flag_values, "Unknown", ssap_field & LLC_GSAP));
 235
 236                 if (is_u) {
 237                         printf(", ctrl 0x%02x: ", control);
 238                 } else {
 239                         printf(", ctrl 0x%04x: ", control);
 240                 }
 241         }
 242
 243         if (ssap == LLCSAP_8021D && dsap == LLCSAP_8021D &&
 244             control == LLC_UI) {
 245                 stp_print(p+3, length-3);
 246                 return (1);
 247         }
 248
 249         if (ssap == LLCSAP_IP && dsap == LLCSAP_IP &&
 250             control == LLC_UI) {
 251                 ip_print(gndo, p+4, length-4);
 252                 return (1);
 253         }
 254
 255         if (ssap == LLCSAP_IPX && dsap == LLCSAP_IPX &&
 256             control == LLC_UI) {
 257                 /*
 258                  * This is an Ethernet_802.2 IPX frame, with an 802.3
 259                  * header and an 802.2 LLC header with the source and
 260                  * destination SAPs being the IPX SAP.
 261                  *
 262                  * Skip DSAP, LSAP, and control field.
 263                  */
 264                 if (eflag)
 265                         printf("IPX 802.2: ");
 266
 267                 ipx_print(p+3, length-3);
 268                 return (1);
 269         }
 270
 271 #ifdef TCPDUMP_DO_SMB
 272         if (ssap == LLCSAP_NETBEUI && dsap == LLCSAP_NETBEUI
 273             && (!(control & LLC_S_FMT) || control == LLC_U_FMT)) {
 274                 /*
 275                  * we don't actually have a full netbeui parser yet, but the
 276                  * smb parser can handle many smb-in-netbeui packets, which
 277                  * is very useful, so we call that
 278                  *
 279                  * We don't call it for S frames, however, just I frames
 280                  * (which are frames that don't have the low-order bit,
 281                  * LLC_S_FMT, set in the first byte of the control field)
 282                  * and UI frames (whose control field is just 3, LLC_U_FMT).
 283                  */
 284
 285                 /*
 286                  * Skip the LLC header.
 287                  */
 288                 if (is_u) {
 289                         p += 3;
 290                         length -= 3;
 291                         caplen -= 3;
 292                 } else {
 293                         p += 4;
 294                         length -= 4;
 295                         caplen -= 4;
 296                 }
 297                 netbeui_print(control, p, length);
 298                 return (1);
 299         }
 300 #endif
 301         if (ssap == LLCSAP_ISONS && dsap == LLCSAP_ISONS
 302             && control == LLC_UI) {
 303                 isoclns_print(p + 3, length - 3, caplen - 3);
 304                 return (1);
 305         }
 306
 307         if (ssap == LLCSAP_SNAP && dsap == LLCSAP_SNAP
 308             && control == LLC_UI) {
 309                 /*
 310                  * XXX - what *is* the right bridge pad value here?
 311                  * Does anybody ever bridge one form of LAN traffic
 312                  * over a networking type that uses 802.2 LLC?
 313                  */
 314                 ret = snap_print(p+3, length-3, caplen-3, extracted_ethertype,
 315                     2);
 316                 if (ret)
 317                         return (ret);
 318         }
 319
 320         if (!eflag) {
 321                 if (ssap == dsap) {
 322                         if (esrc == NULL || edst == NULL)
 323                                 (void)printf("%s ", tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
 324                         else
 325                                 (void)printf("%s > %s %s ",
 326                                                 etheraddr_string(esrc),
 327                                                 etheraddr_string(edst),
 328                                                 tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
 329                 } else {
 330                         if (esrc == NULL || edst == NULL)
 331                                 (void)printf("%s > %s ",
 332                                         tok2str(llc_values, "Unknown SSAP 0x%02x", ssap),
 333                                         tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
 334                         else
 335                                 (void)printf("%s %s > %s %s ",
 336                                         etheraddr_string(esrc),
 337                                         tok2str(llc_values, "Unknown SSAP 0x%02x", ssap),
 338                                         etheraddr_string(edst),
 339                                         tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
 340                 }
 341         }
 342
 343         if (is_u) {
 344                 printf("Unnumbered, %s, Flags [%s], length %u",
 345                        tok2str(llc_cmd_values, "%02x", LLC_U_CMD(control)),
 346                        tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_U_POLL)),
 347                        length);
 348
 349                 p += 3;
 350                 length -= 3;
 351                 caplen -= 3;
 352
 353                 if ((control & ~LLC_U_POLL) == LLC_XID) {
 354                         if (*p == LLC_XID_FI) {
 355                                 printf(": %02x %02x", p[1], p[2]);
 356                                 p += 3;
 357                                 length -= 3;
 358                                 caplen -= 3;
 359                         }
 360                 }
 361         } else {
 362                 if ((control & LLC_S_FMT) == LLC_S_FMT) {
 363                         (void)printf("Supervisory, %s, rcv seq %u, Flags [%s], length %u",
 364                                 tok2str(llc_supervisory_values,"?",LLC_S_CMD(control)),
 365                                 LLC_IS_NR(control),
 366                                 tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_IS_POLL)),
 367                                 length);
 368                 } else {
 369                         (void)printf("Information, send seq %u, rcv seq %u, Flags [%s], length %u",
 370                                 LLC_I_NS(control),
 371                                 LLC_IS_NR(control),
 372                                 tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_IS_POLL)),
 373                                 length);
 374                 }
 375                 p += 4;
 376                 length -= 4;
 377                 caplen -= 4;
 378         }
 379         return(1);
 380 }
 381
 382 int
 383 snap_print(const u_char *p, u_int length, u_int caplen,
 384     u_short *extracted_ethertype, u_int bridge_pad)
 385 {
 386         u_int32_t orgcode;
 387         register u_short et;
 388         register int ret;
 389
 390         TCHECK2(*p, 5);
 391         orgcode = EXTRACT_24BITS(p);
 392         et = EXTRACT_16BITS(p + 3);
 393
 394         if (eflag) {
 395                 const struct tok *tok = null_values;
 396                 const struct oui_tok *otp;
 397
 398                 for (otp = &oui_to_tok[0]; otp->tok != NULL; otp++) {
 399                         if (otp->oui == orgcode) {
 400                                 tok = otp->tok;
 401                                 break;
 402                         }
 403                 }
 404                 (void)printf("oui %s (0x%06x), %s %s (0x%04x): ",
 405                      tok2str(oui_values, "Unknown", orgcode),
 406                      orgcode,
 407                      (orgcode == 0x000000 ? "ethertype" : "pid"),
 408                      tok2str(tok, "Unknown", et),
 409                      et);
 410         }
 411         p += 5;
 412         length -= 5;
 413         caplen -= 5;
 414
 415         switch (orgcode) {
 416         case OUI_ENCAP_ETHER:
 417         case OUI_CISCO_90:
 418                 /*
 419                  * This is an encapsulated Ethernet packet,
 420                  * or a packet bridged by some piece of
 421                  * Cisco hardware; the protocol ID is
 422                  * an Ethernet protocol type.
 423                  */
 424                 ret = ether_encap_print(et, p, length, caplen,
 425                     extracted_ethertype);
 426                 if (ret)
 427                         return (ret);
 428                 break;
 429
 430         case OUI_APPLETALK:
 431                 if (et == ETHERTYPE_ATALK) {
 432                         /*
 433                          * No, I have no idea why Apple used one
 434                          * of their own OUIs, rather than
 435                          * 0x000000, and an Ethernet packet
 436                          * type, for Appletalk data packets,
 437                          * but used 0x000000 and an Ethernet
 438                          * packet type for AARP packets.
 439                          */
 440                         ret = ether_encap_print(et, p, length, caplen,
 441                             extracted_ethertype);
 442                         if (ret)
 443                                 return (ret);
 444                 }
 445                 break;
 446
 447         case OUI_CISCO:
 448                 switch (et) {
 449                 case PID_CISCO_CDP:
 450                         cdp_print(p, length, caplen);
 451                         return (1);
 452                 case PID_CISCO_DTP:
 453                         dtp_print(p, length);
 454                         return (1);
 455                 case PID_CISCO_UDLD:
 456                         udld_print(p, length);
 457                         return (1);
 458                 case PID_CISCO_VTP:
 459                         vtp_print(p, length);
 460                         return (1);
 461                 case PID_CISCO_PVST:
 462                         stp_print(p, length);
 463                         return (1);
 464                 default:
 465                         break;
 466                 }
 467
 468         case OUI_RFC2684:
 469                 switch (et) {
 470
 471                 case PID_RFC2684_ETH_FCS:
 472                 case PID_RFC2684_ETH_NOFCS:
 473                         /*
 474                          * XXX - remove the last two bytes for
 475                          * PID_RFC2684_ETH_FCS?
 476                          */
 477                         /*
 478                          * Skip the padding.
 479                          */
 480                         TCHECK2(*p, bridge_pad);
 481                         caplen -= bridge_pad;
 482                         length -= bridge_pad;
 483                         p += bridge_pad;
 484
 485                         /*
 486                          * What remains is an Ethernet packet.
 487                          */
 488                         ether_print(p, length, caplen);
 489                         return (1);
 490
 491                 case PID_RFC2684_802_5_FCS:
 492                 case PID_RFC2684_802_5_NOFCS:
 493                         /*
 494                          * XXX - remove the last two bytes for
 495                          * PID_RFC2684_ETH_FCS?
 496                          */
 497                         /*
 498                          * Skip the padding, but not the Access
 499                          * Control field.
 500                          */
 501                         TCHECK2(*p, bridge_pad);
 502                         caplen -= bridge_pad;
 503                         length -= bridge_pad;
 504                         p += bridge_pad;
 505
 506                         /*
 507                          * What remains is an 802.5 Token Ring
 508                          * packet.
 509                          */
 510                         token_print(p, length, caplen);
 511                         return (1);
 512
 513                 case PID_RFC2684_FDDI_FCS:
 514                 case PID_RFC2684_FDDI_NOFCS:
 515                         /*
 516                          * XXX - remove the last two bytes for
 517                          * PID_RFC2684_ETH_FCS?
 518                          */
 519                         /*
 520                          * Skip the padding.
 521                          */
 522                         TCHECK2(*p, bridge_pad + 1);
 523                         caplen -= bridge_pad + 1;
 524                         length -= bridge_pad + 1;
 525                         p += bridge_pad + 1;
 526
 527                         /*
 528                          * What remains is an FDDI packet.
 529                          */
 530                         fddi_print(p, length, caplen);
 531                         return (1);
 532
 533                 case PID_RFC2684_BPDU:
 534                         stp_print(p, length);
 535                         return (1);
 536                 }
 537         }
 538         return (0);
 539
 540 trunc:
 541         (void)printf("[|snap]");
 542         return (1);
 543 }
 544
 545
 546 /*
 547  * Local Variables:
 548  * c-style: whitesmith
 549  * c-basic-offset: 8
 550  * End:
 551  */