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 1.61.2.4 2005/04/26 07:27:16 guy 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_PROWAYNM, "ProWay NM" },
  56         { LLCSAP_8021D,    "STP" },
  57         { LLCSAP_RS511,    "RS511" },
  58         { LLCSAP_ISO8208,  "ISO8208" },
  59         { LLCSAP_PROWAY,   "ProWay" },
  60         { LLCSAP_SNAP,     "SNAP" },
  61         { LLCSAP_IPX,      "IPX" },
  62         { LLCSAP_NETBEUI,  "NetBeui" },
  63         { LLCSAP_ISONS,    "OSI" },
  64         { 0,               NULL },
  65 };
  66
  67 static struct tok cmd2str[] = {
  68         { LLC_UI,       "ui" },
  69         { LLC_TEST,     "test" },
  70         { LLC_XID,      "xid" },
  71         { LLC_UA,       "ua" },
  72         { LLC_DISC,     "disc" },
  73         { LLC_DM,       "dm" },
  74         { LLC_SABME,    "sabme" },
  75         { LLC_FRMR,     "frmr" },
  76         { 0,            NULL }
  77 };
  78
  79 static const struct tok cisco_values[] = {
  80         { PID_CISCO_CDP, "CDP" },
  81         { 0,             NULL }
  82 };
  83
  84 static const struct tok bridged_values[] = {
  85         { PID_RFC2684_ETH_FCS,     "Ethernet + FCS" },
  86         { PID_RFC2684_ETH_NOFCS,   "Ethernet w/o FCS" },
  87         { PID_RFC2684_802_4_FCS,   "802.4 + FCS" },
  88         { PID_RFC2684_802_4_NOFCS, "802.4 w/o FCS" },
  89         { PID_RFC2684_802_5_FCS,   "Token Ring + FCS" },
  90         { PID_RFC2684_802_5_NOFCS, "Token Ring w/o FCS" },
  91         { PID_RFC2684_FDDI_FCS,    "FDDI + FCS" },
  92         { PID_RFC2684_FDDI_NOFCS,  "FDDI w/o FCS" },
  93         { PID_RFC2684_802_6_FCS,   "802.6 + FCS" },
  94         { PID_RFC2684_802_6_NOFCS, "802.6 w/o FCS" },
  95         { PID_RFC2684_BPDU,        "BPDU" },
  96         { 0,                       NULL },
  97 };
  98
  99 struct oui_tok {
 100         u_int32_t       oui;
 101         const struct tok *tok;
 102 };
 103
 104 static const struct oui_tok oui_to_tok[] = {
 105         { OUI_ENCAP_ETHER, ethertype_values },
 106         { OUI_CISCO_90, ethertype_values },     /* uses some Ethertype values */
 107         { OUI_APPLETALK, ethertype_values },    /* uses some Ethertype values */
 108         { OUI_CISCO, cisco_values },
 109         { OUI_RFC2684, bridged_values },        /* bridged, RFC 2427 FR or RFC 2864 ATM */
 110         { 0, NULL }
 111 };
 112
 113 /*
 114  * Returns non-zero IFF it succeeds in printing the header
 115  */
 116 int
 117 llc_print(const u_char *p, u_int length, u_int caplen,
 118           const u_char *esrc, const u_char *edst, u_short *extracted_ethertype)
 119 {
 120         u_int8_t dsap, ssap;
 121         u_int16_t control;
 122         int is_u;
 123         register int ret;
 124
 125         if (caplen < 3) {
 126                 (void)printf("[|llc]");
 127                 default_print((u_char *)p, caplen);
 128                 return(0);
 129         }
 130
 131         dsap = *p;
 132         ssap = *(p + 1);
 133
 134         /*
 135          * OK, what type of LLC frame is this?  The length
 136          * of the control field depends on that - I frames
 137          * have a two-byte control field, and U frames have
 138          * a one-byte control field.
 139          */
 140         control = *(p + 2);
 141         if ((control & LLC_U_FMT) == LLC_U_FMT) {
 142                 /*
 143                  * U frame.
 144                  */
 145                 is_u = 1;
 146         } else {
 147                 /*
 148                  * The control field in I and S frames is
 149                  * 2 bytes...
 150                  */
 151                 if (caplen < 4) {
 152                         (void)printf("[|llc]");
 153                         default_print((u_char *)p, caplen);
 154                         return(0);
 155                 }
 156
 157                 /*
 158                  * ...and is little-endian.
 159                  */
 160                 control = EXTRACT_LE_16BITS(p + 2);
 161                 is_u = 0;
 162         }
 163
 164         if (ssap == LLCSAP_GLOBAL && dsap == LLCSAP_GLOBAL) {
 165                 /*
 166                  * This is an Ethernet_802.3 IPX frame; it has an
 167                  * 802.3 header (i.e., an Ethernet header where the
 168                  * type/length field is <= ETHERMTU, i.e. it's a length
 169                  * field, not a type field), but has no 802.2 header -
 170                  * the IPX packet starts right after the Ethernet header,
 171                  * with a signature of two bytes of 0xFF (which is
 172                  * LLCSAP_GLOBAL).
 173                  *
 174                  * (It might also have been an Ethernet_802.3 IPX at
 175                  * one time, but got bridged onto another network,
 176                  * such as an 802.11 network; this has appeared in at
 177                  * least one capture file.)
 178                  */
 179
 180             if (eflag)
 181                 printf("IPX-802.3: ");
 182
 183             ipx_print(p, length);
 184             return (1);
 185         }
 186
 187         if (eflag) {
 188                 if (is_u) {
 189                         printf("LLC, dsap %s (0x%02x), ssap %s (0x%02x), cmd 0x%02x: ",
 190                             tok2str(llc_values, "Unknown", dsap),
 191                             dsap,
 192                             tok2str(llc_values, "Unknown", ssap),
 193                             ssap,
 194                             control);
 195                 } else {
 196                         printf("LLC, dsap %s (0x%02x), ssap %s (0x%02x), cmd 0x%04x: ",
 197                             tok2str(llc_values, "Unknown", dsap),
 198                             dsap,
 199                             tok2str(llc_values, "Unknown", ssap),
 200                             ssap,
 201                             control);
 202                 }
 203         }
 204
 205         if (ssap == LLCSAP_8021D && dsap == LLCSAP_8021D &&
 206             control == LLC_UI) {
 207                 stp_print(p+3, length-3);
 208                 return (1);
 209         }
 210
 211         if (ssap == LLCSAP_IP && dsap == LLCSAP_IP &&
 212             control == LLC_UI) {
 213                 ip_print(gndo, p+4, length-4);
 214                 return (1);
 215         }
 216
 217         if (ssap == LLCSAP_IPX && dsap == LLCSAP_IPX &&
 218             control == LLC_UI) {
 219                 /*
 220                  * This is an Ethernet_802.2 IPX frame, with an 802.3
 221                  * header and an 802.2 LLC header with the source and
 222                  * destination SAPs being the IPX SAP.
 223                  *
 224                  * Skip DSAP, LSAP, and control field.
 225                  */
 226                 printf("(NOV-802.2) ");
 227                 ipx_print(p+3, length-3);
 228                 return (1);
 229         }
 230
 231 #ifdef TCPDUMP_DO_SMB
 232         if (ssap == LLCSAP_NETBEUI && dsap == LLCSAP_NETBEUI
 233             && (!(control & LLC_S_FMT) || control == LLC_U_FMT)) {
 234                 /*
 235                  * we don't actually have a full netbeui parser yet, but the
 236                  * smb parser can handle many smb-in-netbeui packets, which
 237                  * is very useful, so we call that
 238                  *
 239                  * We don't call it for S frames, however, just I frames
 240                  * (which are frames that don't have the low-order bit,
 241                  * LLC_S_FMT, set in the first byte of the control field)
 242                  * and UI frames (whose control field is just 3, LLC_U_FMT).
 243                  */
 244
 245                 /*
 246                  * Skip the LLC header.
 247                  */
 248                 if (is_u) {
 249                         p += 3;
 250                         length -= 3;
 251                         caplen -= 3;
 252                 } else {
 253                         p += 4;
 254                         length -= 4;
 255                         caplen -= 4;
 256                 }
 257                 netbeui_print(control, p, length);
 258                 return (1);
 259         }
 260 #endif
 261         if (ssap == LLCSAP_ISONS && dsap == LLCSAP_ISONS
 262             && control == LLC_UI) {
 263                 isoclns_print(p + 3, length - 3, caplen - 3);
 264                 return (1);
 265         }
 266
 267         if (ssap == LLCSAP_SNAP && dsap == LLCSAP_SNAP
 268             && control == LLC_UI) {
 269                 /*
 270                  * XXX - what *is* the right bridge pad value here?
 271                  * Does anybody ever bridge one form of LAN traffic
 272                  * over a networking type that uses 802.2 LLC?
 273                  */
 274                 ret = snap_print(p+3, length-3, caplen-3, extracted_ethertype,
 275                     2);
 276                 if (ret)
 277                         return (ret);
 278         }
 279
 280         if (!eflag) {
 281                 if ((ssap & ~LLC_GSAP) == dsap) {
 282                         if (esrc == NULL || edst == NULL)
 283                                 (void)printf("%s ", llcsap_string(dsap));
 284                         else
 285                                 (void)printf("%s > %s %s ",
 286                                                 etheraddr_string(esrc),
 287                                                 etheraddr_string(edst),
 288                                                 llcsap_string(dsap));
 289                 } else {
 290                         if (esrc == NULL || edst == NULL)
 291                                 (void)printf("%s > %s ",
 292                                         llcsap_string(ssap & ~LLC_GSAP),
 293                                         llcsap_string(dsap));
 294                         else
 295                                 (void)printf("%s %s > %s %s ",
 296                                         etheraddr_string(esrc),
 297                                         llcsap_string(ssap & ~LLC_GSAP),
 298                                         etheraddr_string(edst),
 299                                         llcsap_string(dsap));
 300                 }
 301         }
 302
 303         if (is_u) {
 304                 const char *m;
 305                 char f;
 306
 307                 m = tok2str(cmd2str, "%02x", LLC_U_CMD(control));
 308                 switch ((ssap & LLC_GSAP) | (control & LLC_U_POLL)) {
 309                         case 0:                 f = 'C'; break;
 310                         case LLC_GSAP:          f = 'R'; break;
 311                         case LLC_U_POLL:        f = 'P'; break;
 312                         case LLC_GSAP|LLC_U_POLL: f = 'F'; break;
 313                         default:                f = '?'; break;
 314                 }
 315
 316                 printf("%s/%c", m, f);
 317
 318                 p += 3;
 319                 length -= 3;
 320                 caplen -= 3;
 321
 322                 if ((control & ~LLC_U_POLL) == LLC_XID) {
 323                         if (*p == LLC_XID_FI) {
 324                                 printf(": %02x %02x", p[1], p[2]);
 325                                 p += 3;
 326                                 length -= 3;
 327                                 caplen -= 3;
 328                         }
 329                 }
 330         } else {
 331                 char f;
 332
 333                 switch ((ssap & LLC_GSAP) | (control & LLC_IS_POLL)) {
 334                         case 0:                 f = 'C'; break;
 335                         case LLC_GSAP:          f = 'R'; break;
 336                         case LLC_IS_POLL:       f = 'P'; break;
 337                         case LLC_GSAP|LLC_IS_POLL: f = 'F'; break;
 338                         default:                f = '?'; break;
 339                 }
 340
 341                 if ((control & LLC_S_FMT) == LLC_S_FMT) {
 342                         static const char *llc_s[] = { "rr", "rej", "rnr", "03" };
 343                         (void)printf("%s (r=%d,%c)",
 344                                 llc_s[LLC_S_CMD(control)],
 345                                 LLC_IS_NR(control),
 346                                 f);
 347                 } else {
 348                         (void)printf("I (s=%d,r=%d,%c)",
 349                                 LLC_I_NS(control),
 350                                 LLC_IS_NR(control),
 351                                 f);
 352                 }
 353                 p += 4;
 354                 length -= 4;
 355                 caplen -= 4;
 356         }
 357         return(1);
 358 }
 359
 360 int
 361 snap_print(const u_char *p, u_int length, u_int caplen,
 362     u_short *extracted_ethertype, u_int bridge_pad)
 363 {
 364         u_int32_t orgcode;
 365         register u_short et;
 366         register int ret;
 367
 368         TCHECK2(*p, 5);
 369         orgcode = EXTRACT_24BITS(p);
 370         et = EXTRACT_16BITS(p + 3);
 371
 372         if (eflag) {
 373                 const struct tok *tok = NULL;
 374                 const struct oui_tok *otp;
 375
 376                 for (otp = &oui_to_tok[0]; otp->tok != NULL; otp++) {
 377                         if (otp->oui == orgcode) {
 378                                 tok = otp->tok;
 379                                 break;
 380                         }
 381                 }
 382                 (void)printf("oui %s (0x%06x), %s %s (0x%04x): ",
 383                      tok2str(oui_values, "Unknown", orgcode),
 384                      orgcode,
 385                      (orgcode == 0x000000 ? "ethertype" : "pid"),
 386                      tok2str(tok, "Unknown", et),
 387                      et);
 388         }
 389         p += 5;
 390         length -= 5;
 391         caplen -= 5;
 392
 393         switch (orgcode) {
 394         case OUI_ENCAP_ETHER:
 395         case OUI_CISCO_90:
 396                 /*
 397                  * This is an encapsulated Ethernet packet,
 398                  * or a packet bridged by some piece of
 399                  * Cisco hardware; the protocol ID is
 400                  * an Ethernet protocol type.
 401                  */
 402                 ret = ether_encap_print(et, p, length, caplen,
 403                     extracted_ethertype);
 404                 if (ret)
 405                         return (ret);
 406                 break;
 407
 408         case OUI_APPLETALK:
 409                 if (et == ETHERTYPE_ATALK) {
 410                         /*
 411                          * No, I have no idea why Apple used one
 412                          * of their own OUIs, rather than
 413                          * 0x000000, and an Ethernet packet
 414                          * type, for Appletalk data packets,
 415                          * but used 0x000000 and an Ethernet
 416                          * packet type for AARP packets.
 417                          */
 418                         ret = ether_encap_print(et, p, length, caplen,
 419                             extracted_ethertype);
 420                         if (ret)
 421                                 return (ret);
 422                 }
 423                 break;
 424
 425         case OUI_CISCO:
 426                 if (et == PID_CISCO_CDP) {
 427                         cdp_print(p, length, caplen);
 428                         return (1);
 429                 }
 430                 break;
 431
 432         case OUI_RFC2684:
 433                 switch (et) {
 434
 435                 case PID_RFC2684_ETH_FCS:
 436                 case PID_RFC2684_ETH_NOFCS:
 437                         /*
 438                          * XXX - remove the last two bytes for
 439                          * PID_RFC2684_ETH_FCS?
 440                          */
 441                         /*
 442                          * Skip the padding.
 443                          */
 444                         TCHECK2(*p, bridge_pad);
 445                         caplen -= bridge_pad;
 446                         length -= bridge_pad;
 447                         p += bridge_pad;
 448
 449                         /*
 450                          * What remains is an Ethernet packet.
 451                          */
 452                         ether_print(p, length, caplen);
 453                         return (1);
 454
 455                 case PID_RFC2684_802_5_FCS:
 456                 case PID_RFC2684_802_5_NOFCS:
 457                         /*
 458                          * XXX - remove the last two bytes for
 459                          * PID_RFC2684_ETH_FCS?
 460                          */
 461                         /*
 462                          * Skip the padding, but not the Access
 463                          * Control field.
 464                          */
 465                         TCHECK2(*p, bridge_pad);
 466                         caplen -= bridge_pad;
 467                         length -= bridge_pad;
 468                         p += bridge_pad;
 469
 470                         /*
 471                          * What remains is an 802.5 Token Ring
 472                          * packet.
 473                          */
 474                         token_print(p, length, caplen);
 475                         return (1);
 476
 477                 case PID_RFC2684_FDDI_FCS:
 478                 case PID_RFC2684_FDDI_NOFCS:
 479                         /*
 480                          * XXX - remove the last two bytes for
 481                          * PID_RFC2684_ETH_FCS?
 482                          */
 483                         /*
 484                          * Skip the padding.
 485                          */
 486                         TCHECK2(*p, bridge_pad + 1);
 487                         caplen -= bridge_pad + 1;
 488                         length -= bridge_pad + 1;
 489                         p += bridge_pad + 1;
 490
 491                         /*
 492                          * What remains is an FDDI packet.
 493                          */
 494                         fddi_print(p, length, caplen);
 495                         return (1);
 496
 497                 case PID_RFC2684_BPDU:
 498                         stp_print(p, length);
 499                         return (1);
 500                 }
 501         }
 502         return (0);
 503
 504 trunc:
 505         (void)printf("[|snap]");
 506         return (1);
 507 }
 508
 509
 510 /*
 511  * Local Variables:
 512  * c-style: whitesmith
 513  * c-basic-offset: 8
 514  * End:
 515  */