epan/dissectors/packet-llc.c

   1 /* packet-llc.c
   2  * Routines for IEEE 802.2 LLC layer
   3  * Gilbert Ramirez <gram@alumni.rice.edu>
   4  *
   5  * $Id$
   6  *
   7  * Wireshark - Network traffic analyzer
   8  * By Gerald Combs <gerald@wireshark.org>
   9  * Copyright 1998 Gerald Combs
  10  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public License
  13  * as published by the Free Software Foundation; either version 2
  14  * of the License, or (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  24  */
  25
  26 #ifdef HAVE_CONFIG_H
  27 # include "config.h"
  28 #endif
  29
  30 #include <glib.h>
  31 #include <epan/packet.h>
  32 #include <epan/oui.h>
  33 #include <epan/xdlc.h>
  34 #include <epan/etypes.h>
  35 #include <epan/llcsaps.h>
  36 #include <epan/bridged_pids.h>
  37 #include <epan/ppptypes.h>
  38 #include <epan/arcnet_pids.h>
  39 #include <epan/conversation.h>
  40 #include "packet-scsi.h"
  41 #include "packet-fc.h"
  42 #include "packet-ip.h"
  43 #include "packet-ipx.h"
  44 #include "packet-netbios.h"
  45 #include "packet-vines.h"
  46 #include "packet-sll.h"
  47 #include <epan/sna-utils.h>
  48
  49 #include "packet-llc.h"
  50
  51 #define UDP_PORT_LLC1   12000
  52 #define UDP_PORT_LLC2   12001
  53 #define UDP_PORT_LLC3   12002
  54 #define UDP_PORT_LLC4   12003
  55 #define UDP_PORT_LLC5   12004
  56
  57 static int proto_llc = -1;
  58 static int hf_llc_dsap = -1;
  59 static int hf_llc_ssap = -1;
  60 static int hf_llc_dsap_ig = -1;
  61 static int hf_llc_ssap_cr = -1;
  62 static int hf_llc_ctrl = -1;
  63 static int hf_llc_n_r = -1;
  64 static int hf_llc_n_s = -1;
  65 static int hf_llc_p = -1;
  66 static int hf_llc_p_ext = -1;
  67 static int hf_llc_f = -1;
  68 static int hf_llc_f_ext = -1;
  69 static int hf_llc_s_ftype = -1;
  70 static int hf_llc_u_modifier_cmd = -1;
  71 static int hf_llc_u_modifier_resp = -1;
  72 static int hf_llc_ftype_i = -1;
  73 static int hf_llc_ftype_s_u = -1;
  74 static int hf_llc_ftype_s_u_ext = -1;
  75 static int hf_llc_type = -1;
  76 static int hf_llc_oui = -1;
  77 static int hf_llc_pid = -1;
  78
  79 static int proto_basicxid = -1;
  80 static int hf_llc_xid_format = -1;
  81 static int hf_llc_xid_types = -1;
  82 static int hf_llc_xid_wsize = -1;
  83
  84 static gint ett_llc = -1;
  85 static gint ett_llc_ctrl = -1;
  86 static gint ett_llc_basicxid = -1;
  87
  88 static dissector_table_t dsap_subdissector_table;
  89 static dissector_table_t xid_subdissector_table;
  90
  91 static dissector_table_t ethertype_subdissector_table;
  92 static dissector_table_t hpteam_subdissector_table;
  93
  94 static dissector_handle_t bpdu_handle;
  95 static dissector_handle_t eth_withoutfcs_handle;
  96 static dissector_handle_t eth_withfcs_handle;
  97 static dissector_handle_t fddi_handle;
  98 static dissector_handle_t tr_handle;
  99 static dissector_handle_t turbo_handle;
 100 static dissector_handle_t mesh_handle;
 101 static dissector_handle_t data_handle;
 102
 103 /*
 104  * Group/Individual bit, in the DSAP.
 105  */
 106 #define DSAP_GI_BIT     0x01
 107
 108 /*
 109  * Command/Response bit, in the SSAP.
 110  *
 111  * The low-order bit of the SSAP apparently determines whether this
 112  * is a request or a response.  (RFC 1390, "Transmission of IP and
 113  * ARP over FDDI Networks", says
 114  *
 115  *      Command frames are identified by having the low order
 116  *      bit of the SSAP address reset to zero.  Response frames
 117  *      have the low order bit of the SSAP address set to one.
 118  *
 119  * and a page I've seen seems to imply that's part of 802.2.)
 120  */
 121 #define SSAP_CR_BIT     0x01
 122
 123 /*
 124  * Mask to extrace the SAP number from the DSAP or the SSAP.
 125  */
 126 #define SAP_MASK        0xFE
 127
 128 /*
 129  * These are for SSAP and DSAP, wth last bit always zero.
 130  * XXX - some DSAPs come in separate "individual" and "group" versions,
 131  * with the last bit 0 and 1, respectively (e.g., LLC Sub-layer Management,
 132  * IBM SNA Path Control, IBM Net Management), but, whilst 0xFE is
 133  * the ISO Network Layer Protocol, 0xFF is the Global LSAP.
 134  */
 135 const value_string sap_vals[] = {
 136         { SAP_NULL,           "NULL LSAP" },
 137         { SAP_LLC_SLMGMT,     "LLC Sub-Layer Management" },
 138         { SAP_SNA_PATHCTRL,   "SNA Path Control" },
 139         { SAP_IP,             "TCP/IP" },
 140         { SAP_SNA1,           "SNA" },
 141         { SAP_SNA2,           "SNA" },
 142         { SAP_PROWAY_NM_INIT, "PROWAY (IEC955) Network Management and Initialization" },
 143         { SAP_NETWARE1,       "NetWare (unofficial?)" },
 144         { SAP_OSINL1,         "ISO Network Layer (OSLAN 1)" },
 145         { SAP_TI,             "Texas Instruments" },
 146         { SAP_OSINL2,         "ISO Network Layer (unofficial?)" },
 147         { SAP_OSINL3,         "ISO Network Layer (unofficial?)" },
 148         { SAP_BPDU,           "Spanning Tree BPDU" },
 149         { SAP_RS511,          "EIA RS-511 Manufacturing Message Service" },
 150         { SAP_OSINL4,         "ISO Network Layer (OSLAN 2)" },
 151         { SAP_X25,            "ISO 8208 (X.25 over 802.2)" },
 152         /*
 153          * XXX - setting the group bit of SAP_X25 make 0x7F; is this just
 154          * a group version of that?
 155          */
 156         { 0x7F,               "ISO 802.2" },
 157         { SAP_XNS,            "XNS" },
 158         { SAP_BACNET,         "BACnet" },
 159         { SAP_NESTAR,         "Nestar" },
 160         { SAP_PROWAY_ASLM,    "PROWAY (IEC955) Active Station List Maintenance" },
 161         { SAP_ARP,            "ARP" },  /* XXX - hand to "dissect_arp()"? */
 162         { SAP_HPJD,           "HP JetDirect Printer" },
 163         { SAP_SNAP,           "SNAP" },
 164         { SAP_VINES1,         "Banyan Vines" },
 165         { SAP_VINES2,         "Banyan Vines" },
 166         { SAP_NETWARE2,       "NetWare" },
 167         { SAP_NETBIOS,        "NetBIOS" },
 168         { SAP_IBMNM,          "IBM Net Management" },
 169         { SAP_HPEXT,          "HP Extended LLC" },
 170         { SAP_UB,             "Ungermann-Bass" },
 171         { SAP_RPL,            "Remote Program Load" },
 172         { SAP_OSINL5,         "ISO Network Layer" },
 173         { SAP_GLOBAL,         "Global LSAP" },
 174         { 0x00,               NULL }
 175 };
 176
 177 /*
 178  * See
 179  *
 180  * http://standards.ieee.org/regauth/oui/oui.txt
 181  *
 182  * http://www.cisco.com/univercd/cc/td/doc/product/lan/trsrb/vlan.htm
 183  *
 184  * for the PIDs for VTP and DRiP that go with an OUI of OUI_CISCO.
 185  */
 186 const value_string oui_vals[] = {
 187         { OUI_ENCAP_ETHER,      "Encapsulated Ethernet" },
 188         { OUI_XEROX,            "Xerox" },
 189 /*
 190 http://www.cisco.com/univercd/cc/td/doc/product/software/ios113ed/113ed_cr/ibm_r/brprt1/brsrb.htm
 191 */
 192         { OUI_CISCO,                    "Cisco" },
 193         { OUI_NORTEL,                   "Nortel Discovery Protocol" },
 194         { OUI_CISCO_90,                 "Cisco IOS 9.0 Compatible" },
 195         { OUI_FORCE10,                  "Force10 Networks" },
 196         { OUI_ERICSSON,                 "Ericsson Group" },
 197         { OUI_CATENA,                   "Catena Networks" },
 198         { OUI_SONY_ERICSSON,    "Sony Ericsson Mobile Communications AB" },
 199         { OUI_SONY_ERICSSON_2,  "Sony Ericsson Mobile Communications AB" },
 200         { OUI_PROFINET,                 "PROFIBUS Nutzerorganisation e.V." },
 201         { OUI_SONY_ERICSSON_3,  "Sony Ericsson Mobile Communications AB" },
 202         { OUI_CIMETRICS,                "Cimetrics" },
 203         { OUI_IEEE_802_3,               "IEEE 802.3" },
 204         { OUI_MEDIA_ENDPOINT,   "Media (TIA TR-41 Committee)" },
 205         { OUI_SONY_ERICSSON_4,  "Sony Ericsson Mobile Communications AB" },
 206         { OUI_ERICSSON_MOBILE,  "Ericsson Mobile Platforms" },
 207         { OUI_SONY_ERICSSON_5,  "Sony Ericsson Mobile Communications AB" },
 208         { OUI_SONY_ERICSSON_6,  "Sony Ericsson Mobile Communications AB" },
 209         { OUI_SONY_ERICSSON_7,  "Sony Ericsson Mobile Communications AB" },
 210         { OUI_SONY_ERICSSON_8,  "Sony Ericsson Mobile Communications AB" },
 211         { OUI_TURBOCELL,                "Karlnet (Turbocell)" },
 212         { OUI_CISCOWL,                  "Cisco Wireless (Aironet) L2" },
 213         { OUI_MARVELL,                  "Marvell Semiconductor" },
 214         { OUI_BRIDGED,                  "Frame Relay or ATM bridged frames" },
 215         { OUI_IEEE_802_1,               "IEEE 802.1 Committee" },
 216         { OUI_ATM_FORUM,                "ATM Forum" },
 217         { OUI_EXTREME,                  "Extreme Networks" },
 218         /* RFC 2427, RFC 2684 */
 219         { OUI_CABLE_BPDU,               "DOCSIS Spanning Tree" }, /* DOCSIS spanning tree BPDU */
 220         { OUI_SIEMENS,                  "Siemens AG" },
 221         { OUI_APPLE_ATALK,              "Apple (AppleTalk)" },
 222         { OUI_HP,                               "Hewlett-Packard" },
 223         { OUI_HP_2,                             "Hewlett-Packard" },
 224         /* Registry Name: PPP Vendor Specific OUI Options */
 225         { OUI_3GPP2,                    "3GPP2 Vendor specific packet ID" },
 226         { OUI_ERICSSON_2,               "Ericsson Group" },
 227         { 0,    NULL }
 228 };
 229
 230 static const value_string format_vals[] = {
 231         { 0x81,        "LLC basic format" },
 232         { 0,           NULL }
 233 };
 234
 235 /*
 236  * Mask to extract the type from XID frame.
 237  */
 238 #define TYPES_MASK      0x1F
 239
 240 static const value_string type_vals[] = {
 241         { 1,           "Type 1 LLC (Class I LLC)" },
 242         { 2,           "Type 2 LLC" },
 243         { 3,           "Type 1 and Type 2 LLCs (Class II LLC)" },
 244         { 4,           "Type 3 LLC" },
 245         { 5,           "Type 1 and Type 3 LLCs (Class III LLC)" },
 246         { 6,           "Type 2 and Type 3 LLCs" },
 247         { 7,           "Type 1 and Type 2 and Type 3 LLCs (Class IV LLC)" },
 248         { 0,           NULL }
 249 };
 250
 251 /*
 252  * Hash table for translating OUIs to an oui_info_t.
 253  */
 254 static GHashTable *oui_info_table = NULL;
 255
 256 /*
 257  * Add an entry for a new OUI.
 258  */
 259 void
 260 llc_add_oui(guint32 oui, const char *table_name, const char *table_ui_name,
 261     hf_register_info *hf_item)
 262 {
 263         oui_info_t *new_info;
 264
 265         new_info = g_malloc(sizeof (oui_info_t));
 266         new_info->table = register_dissector_table(table_name,
 267             table_ui_name, FT_UINT16, BASE_HEX);
 268         new_info->field_info = hf_item;
 269
 270         /*
 271          * Create the hash table for OUI information, if it doesn't
 272          * already exist.
 273          */
 274         if (oui_info_table == NULL) {
 275                 oui_info_table = g_hash_table_new(g_direct_hash,
 276                     g_direct_equal);
 277         }
 278         g_hash_table_insert(oui_info_table, GUINT_TO_POINTER(oui), new_info);
 279 }
 280
 281 void
 282 capture_llc(const guchar *pd, int offset, int len, packet_counts *ld) {
 283
 284         int             is_snap;
 285         guint16         control;
 286         int             llc_header_len;
 287
 288         if (!BYTES_ARE_IN_FRAME(offset, len, 2)) {
 289                 ld->other++;
 290                 return;
 291         }
 292         is_snap = (pd[offset] == SAP_SNAP) && (pd[offset+1] == SAP_SNAP);
 293         llc_header_len = 2;     /* DSAP + SSAP */
 294
 295         /*
 296          * XXX - the page referred to in the comment above about the
 297          * Command/Response bit also implies that LLC Type 2 always
 298          * uses extended operation, so we don't need to determine
 299          * whether it's basic or extended operation; is that the case?
 300          */
 301         control = get_xdlc_control(pd, offset+2, pd[offset+1] & SSAP_CR_BIT);
 302         llc_header_len += XDLC_CONTROL_LEN(control, TRUE);
 303         if (!BYTES_ARE_IN_FRAME(offset, len, llc_header_len)) {
 304                 ld->other++;
 305                 return;
 306         }
 307
 308         if (!XDLC_IS_INFORMATION(control)) {
 309                 ld->other++;
 310                 return;
 311         }
 312         if (is_snap)
 313                 capture_snap(pd, offset+llc_header_len, len, ld);
 314         else {
 315                 /* non-SNAP */
 316                 switch (pd[offset]) {
 317
 318                 case SAP_IP:
 319                         capture_ip(pd, offset + llc_header_len, len, ld);
 320                         break;
 321
 322                 case SAP_NETWARE1:
 323                 case SAP_NETWARE2:
 324                         capture_ipx(ld);
 325                         break;
 326
 327                 case SAP_NETBIOS:
 328                         capture_netbios(ld);
 329                         break;
 330
 331                 case SAP_VINES1:
 332                 case SAP_VINES2:
 333                         capture_vines(ld);
 334                         break;
 335
 336                 default:
 337                         ld->other++;
 338                         break;
 339                 }
 340         }
 341 }
 342
 343 void
 344 capture_snap(const guchar *pd, int offset, int len, packet_counts *ld)
 345 {
 346         guint32         oui;
 347         guint16         etype;
 348
 349         if (!BYTES_ARE_IN_FRAME(offset, len, 5)) {
 350                 ld->other++;
 351                 return;
 352         }
 353
 354         oui = pd[offset] << 16 | pd[offset+1] << 8 | pd[offset+2];
 355         etype = pntohs(&pd[offset+3]);
 356         switch (oui) {
 357
 358         case OUI_ENCAP_ETHER:
 359         case OUI_CISCO_90:
 360         case OUI_APPLE_ATALK:
 361                 /* No, I have no idea why Apple used
 362                    one of their own OUIs, rather than
 363                    OUI_ENCAP_ETHER, and an Ethernet
 364                    packet type as protocol ID, for
 365                    AppleTalk data packets - but used
 366                    OUI_ENCAP_ETHER and an Ethernet
 367                    packet type for AARP packets. */
 368                 capture_ethertype(etype, pd, offset+5, len, ld);
 369                 break;
 370
 371         case OUI_CISCO:
 372                 capture_ethertype(etype, pd, offset+5, len, ld);
 373                 break;
 374
 375         case OUI_MARVELL:
 376                 /*
 377                  * OLPC packet.  The PID is an Ethertype, but
 378                  * there's a mesh header between the PID and
 379                  * the payload.  (We assume the header is
 380                  * 5 bytes, for now).
 381                  */
 382                 capture_ethertype(etype, pd, offset+5+5, len, ld);
 383                 break;
 384
 385         default:
 386                 ld->other++;
 387                 break;
 388         }
 389 }
 390
 391 /* Used only for U frames */
 392 static const xdlc_cf_items llc_cf_items = {
 393         NULL,
 394         NULL,
 395         &hf_llc_p,
 396         &hf_llc_f,
 397         NULL,
 398         &hf_llc_u_modifier_cmd,
 399         &hf_llc_u_modifier_resp,
 400         NULL,
 401         &hf_llc_ftype_s_u
 402 };
 403
 404 /* Used only for I and S frames */
 405 static const xdlc_cf_items llc_cf_items_ext = {
 406         &hf_llc_n_r,
 407         &hf_llc_n_s,
 408         &hf_llc_p_ext,
 409         &hf_llc_f_ext,
 410         &hf_llc_s_ftype,
 411         NULL,
 412         NULL,
 413         &hf_llc_ftype_i,
 414         &hf_llc_ftype_s_u_ext
 415 };
 416
 417 static void
 418 dissect_basicxid(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 419 {
 420         proto_tree      *xid_tree = NULL;
 421         proto_item      *ti = NULL;
 422         guint8          format, types, wsize;
 423
 424         col_set_str(pinfo->cinfo, COL_PROTOCOL, "XID");
 425         col_clear(pinfo->cinfo, COL_INFO);
 426
 427         format = tvb_get_guint8(tvb, 0);
 428         if (tree) {
 429                 ti = proto_tree_add_item(tree, proto_basicxid, tvb, 0, -1, ENC_NA);
 430                 xid_tree = proto_item_add_subtree(ti, ett_llc_basicxid);
 431                 proto_tree_add_uint(xid_tree, hf_llc_xid_format, tvb, 0,
 432                         1, format);
 433         } else
 434                 xid_tree = NULL;
 435         col_append_str(pinfo->cinfo, COL_INFO,
 436                     "Basic Format");
 437
 438         types = tvb_get_guint8(tvb, 1);
 439         if (tree) {
 440                 proto_tree_add_uint(xid_tree, hf_llc_xid_types, tvb, 1,
 441                         1, types & TYPES_MASK);
 442         }
 443         if (check_col(pinfo->cinfo, COL_INFO)) {
 444                 col_append_fstr(pinfo->cinfo, COL_INFO,
 445                     "; %s", val_to_str(types & TYPES_MASK, type_vals, "0x%02x")
 446                 );
 447         }
 448         wsize = tvb_get_guint8(tvb, 2);
 449         if (tree) {
 450                 proto_tree_add_uint(xid_tree, hf_llc_xid_wsize, tvb, 2,
 451                         1, (wsize & 0xFE) >> 1);
 452         }
 453         if (check_col(pinfo->cinfo, COL_INFO)) {
 454                 col_append_fstr(pinfo->cinfo, COL_INFO,
 455                     "; Window Size %d", (wsize & 0xFE) >> 1);
 456         }
 457 }
 458
 459 static void
 460 dissect_llc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 461 {
 462         proto_tree      *llc_tree = NULL;
 463         proto_item      *ti = NULL;
 464         int             is_snap;
 465         guint16         control;
 466         int             llc_header_len;
 467         guint8          dsap, ssap, format;
 468         tvbuff_t        *next_tvb;
 469
 470         col_set_str(pinfo->cinfo, COL_PROTOCOL, "LLC");
 471         col_clear(pinfo->cinfo, COL_INFO);
 472
 473         dsap = tvb_get_guint8(tvb, 0);
 474         if (tree) {
 475                 ti = proto_tree_add_item(tree, proto_llc, tvb, 0, -1, ENC_NA);
 476                 llc_tree = proto_item_add_subtree(ti, ett_llc);
 477                 proto_tree_add_uint(llc_tree, hf_llc_dsap, tvb, 0,
 478                         1, dsap & SAP_MASK);
 479                 proto_tree_add_boolean(llc_tree, hf_llc_dsap_ig, tvb, 0,
 480                         1, dsap & DSAP_GI_BIT);
 481         } else
 482                 llc_tree = NULL;
 483
 484         ssap = tvb_get_guint8(tvb, 1);
 485         if (tree) {
 486                 proto_tree_add_uint(llc_tree, hf_llc_ssap, tvb, 1,
 487                         1, ssap & SAP_MASK);
 488                 proto_tree_add_boolean(llc_tree, hf_llc_ssap_cr, tvb, 1,
 489                         1, ssap & SSAP_CR_BIT);
 490         } else
 491                 llc_tree = NULL;
 492
 493         is_snap = (dsap == SAP_SNAP) && (ssap == SAP_SNAP);
 494         llc_header_len = 2;     /* DSAP + SSAP */
 495
 496         /*
 497          * XXX - the page referred to in the comment above about the
 498          * Command/Response bit also implies that LLC Type 2 always
 499          * uses extended operation, so we don't need to determine
 500          * whether it's basic or extended operation; is that the case?
 501          */
 502         control = dissect_xdlc_control(tvb, 2, pinfo, llc_tree,
 503                                 hf_llc_ctrl, ett_llc_ctrl,
 504                                 &llc_cf_items, &llc_cf_items_ext,
 505                                 NULL, NULL, ssap & SSAP_CR_BIT, TRUE, FALSE);
 506         llc_header_len += XDLC_CONTROL_LEN(control, TRUE);
 507         if (is_snap)
 508                 llc_header_len += 5;    /* 3 bytes of OUI, 2 bytes of protocol ID */
 509
 510         if (tree)
 511                 proto_item_set_len(ti, llc_header_len);
 512
 513         if (is_snap) {
 514                 dissect_snap(tvb, 2+XDLC_CONTROL_LEN(control, TRUE), pinfo, tree, llc_tree, control,
 515                     hf_llc_oui, hf_llc_type, hf_llc_pid, 2);
 516         }
 517         else {
 518                 if (check_col(pinfo->cinfo, COL_INFO)) {
 519                         col_append_fstr(pinfo->cinfo, COL_INFO,
 520                             "; DSAP %s %s, SSAP %s %s",
 521                             val_to_str(dsap & SAP_MASK, sap_vals, "0x%02x"),
 522                             dsap & DSAP_GI_BIT ?
 523                               "Group" : "Individual",
 524                             val_to_str(ssap & SAP_MASK, sap_vals, "0x%02x"),
 525                             ssap & SSAP_CR_BIT ?
 526                               "Response" : "Command"
 527                         );
 528                 }
 529
 530                 if (tvb_length_remaining(tvb, llc_header_len) > 0) {
 531                         next_tvb = tvb_new_subset_remaining(tvb, llc_header_len);
 532                         if (XDLC_IS_INFORMATION(control)) {
 533                                 /*
 534                                  * Non-SNAP I or UI frame.
 535                                  * Try the regular LLC subdissector table
 536                                  * with the DSAP.
 537                                  */
 538                                 if (!dissector_try_uint(dsap_subdissector_table,
 539                                     dsap, next_tvb, pinfo, tree)) {
 540                                         call_dissector(data_handle, next_tvb,
 541                                             pinfo, tree);
 542                                 }
 543                         } else if ((control & (XDLC_U_MODIFIER_MASK|XDLC_U))
 544                             == (XDLC_XID|XDLC_U)) {
 545                                 /*
 546                                  * Non-SNAP XID frame.
 547                                  * Test for LLC basic format first
 548                                  */
 549                                 format = tvb_get_guint8(next_tvb, 0);
 550                                 if (format == 0x81) {
 551                                     dissect_basicxid(next_tvb, pinfo, tree);
 552                                 } else {
 553                                 /*
 554                                  * Try the XID LLC subdissector table
 555                                  * with the DSAP.
 556                                  */
 557                                     if (!dissector_try_uint(
 558                                         xid_subdissector_table, dsap, next_tvb,
 559                                         pinfo, tree)) {
 560                                             call_dissector(data_handle,
 561                                                 next_tvb, pinfo, tree);
 562                                     }
 563                                 }
 564                         } else {
 565                                 call_dissector(data_handle, next_tvb, pinfo,
 566                                     tree);
 567                         }
 568                 }
 569         }
 570 }
 571
 572 /*
 573  * Dissect SNAP header; used elsewhere, e.g. in the Frame Relay dissector.
 574  */
 575 void
 576 dissect_snap(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree,
 577     proto_tree *snap_tree, int control, int hf_oui, int hf_type, int hf_pid,
 578     int bridge_pad)
 579 {
 580         guint32         oui;
 581         guint16         etype;
 582         tvbuff_t        *next_tvb;
 583         oui_info_t      *oui_info;
 584         dissector_table_t subdissector_table;
 585         int             hf;
 586         int             mesh_header_len;
 587
 588         /*
 589          * XXX - what about non-UI frames?
 590          */
 591         oui =   tvb_get_ntoh24(tvb, offset);
 592         etype = tvb_get_ntohs(tvb, offset+3);
 593
 594         if (check_col(pinfo->cinfo, COL_INFO)) {
 595                 col_append_fstr(pinfo->cinfo, COL_INFO,
 596                     "; SNAP, OUI 0x%06X (%s), PID 0x%04X",
 597                     oui, val_to_str(oui, oui_vals, "Unknown"), etype);
 598         }
 599         if (tree) {
 600                 proto_tree_add_uint(snap_tree, hf_oui, tvb, offset, 3, oui);
 601         }
 602
 603         switch (oui) {
 604
 605         case OUI_HP_2:
 606                 oui_info = get_snap_oui_info(oui);
 607                 hf = *oui_info->field_info->p_id;
 608                 subdissector_table = oui_info->table;
 609                 proto_tree_add_uint(snap_tree, hf, tvb, offset+3, 2, etype);
 610                 next_tvb = tvb_new_subset_remaining(tvb, offset+5);
 611
 612                 if(!dissector_try_uint(hpteam_subdissector_table,etype, next_tvb, pinfo, tree))
 613                         call_dissector(data_handle, next_tvb, pinfo, tree);
 614                 break;
 615
 616         case OUI_ENCAP_ETHER:
 617         case OUI_CISCO_90:
 618         case OUI_APPLE_ATALK:
 619                 /* No, I have no idea why Apple used
 620                    one of their own OUIs, rather than
 621                    OUI_ENCAP_ETHER, and an Ethernet
 622                    packet type as protocol ID, for
 623                    AppleTalk data packets - but used
 624                    OUI_ENCAP_ETHER and an Ethernet
 625                    packet type for AARP packets. */
 626                 if (XDLC_IS_INFORMATION(control)) {
 627                         if (tree) {
 628                                 proto_tree_add_uint(snap_tree, hf_type,
 629                                     tvb, offset+3, 2, etype);
 630                         }
 631                         next_tvb = tvb_new_subset_remaining(tvb, offset+5);
 632                         if (!dissector_try_uint(ethertype_subdissector_table,
 633                             etype, next_tvb, pinfo, tree))
 634                                 call_dissector(data_handle, next_tvb, pinfo,
 635                                     tree);
 636                 } else {
 637                         next_tvb = tvb_new_subset_remaining(tvb, offset+5);
 638                         call_dissector(data_handle, next_tvb, pinfo, tree);
 639                 }
 640                 break;
 641
 642         case OUI_BRIDGED:
 643                 /*
 644                  * MAC frames bridged over ATM (RFC 2684) or Frame Relay
 645                  * (RFC 2427).
 646                  *
 647                  * We have to figure out how much padding to put
 648                  * into the frame.  We were handed a "bridge_pad"
 649                  * argument which should be 0 for Frame Relay and
 650                  * 2 for ATM; we add to that the amount of padding
 651                  * common to both bridging types.
 652                  */
 653                 if (tree) {
 654                         proto_tree_add_uint(snap_tree, hf_pid, tvb, offset+3, 2,
 655                             etype);
 656                 }
 657
 658                 switch (etype) {
 659
 660                 case BPID_ETH_WITH_FCS:
 661                         next_tvb = tvb_new_subset_remaining(tvb, offset+5+bridge_pad);
 662                         call_dissector(eth_withfcs_handle, next_tvb, pinfo,
 663                             tree);
 664                         break;
 665
 666                 case BPID_ETH_WITHOUT_FCS:
 667                         next_tvb = tvb_new_subset_remaining(tvb, offset+5+bridge_pad);
 668                         call_dissector(eth_withoutfcs_handle, next_tvb, pinfo, tree);
 669                         break;
 670
 671                 case BPID_802_5_WITH_FCS:
 672                 case BPID_802_5_WITHOUT_FCS:
 673                         /*
 674                          * We treat the last padding byte as the Access
 675                          * Control byte, as that's what the Token
 676                          * Ring dissector expects the first byte to
 677                          * be.
 678                          */
 679                         next_tvb = tvb_new_subset_remaining(tvb, offset+5+bridge_pad);
 680                         call_dissector(tr_handle, next_tvb, pinfo, tree);
 681                         break;
 682
 683                 case BPID_FDDI_WITH_FCS:
 684                 case BPID_FDDI_WITHOUT_FCS:
 685                         next_tvb = tvb_new_subset_remaining(tvb, offset+5+1+bridge_pad);
 686                         call_dissector(fddi_handle, next_tvb, pinfo, tree);
 687                         break;
 688
 689                 case BPID_BPDU:
 690                         next_tvb = tvb_new_subset_remaining(tvb, offset+5);
 691                         call_dissector(bpdu_handle, next_tvb, pinfo, tree);
 692                         break;
 693
 694                 default:
 695                         next_tvb = tvb_new_subset_remaining(tvb, offset+5);
 696                         call_dissector(data_handle, next_tvb, pinfo, tree);
 697                         break;
 698                 }
 699                 break;
 700
 701         case OUI_CABLE_BPDU:    /* DOCSIS cable modem spanning tree BPDU */
 702                 if (tree) {
 703                         proto_tree_add_uint(snap_tree, hf_pid, tvb, offset+3, 2,
 704                             etype);
 705                 }
 706                 next_tvb = tvb_new_subset_remaining(tvb, offset+5);
 707                 call_dissector(bpdu_handle, next_tvb, pinfo, tree);
 708                 break;
 709
 710         case OUI_TURBOCELL:
 711                 next_tvb = tvb_new_subset_remaining(tvb, offset+3);
 712                 call_dissector(turbo_handle, next_tvb, pinfo, tree);
 713                 break;
 714
 715         case OUI_MARVELL:
 716                 /*
 717                  * OLPC packet.  The PID is an Ethertype, but
 718                  * there's a mesh header between the PID and
 719                  * the payload.
 720                  */
 721                 if (XDLC_IS_INFORMATION(control)) {
 722                         if (tree) {
 723                                 proto_tree_add_uint(snap_tree, hf_type,
 724                                     tvb, offset+3, 2, etype);
 725                         }
 726                         next_tvb = tvb_new_subset_remaining(tvb, offset+5);
 727                         mesh_header_len = call_dissector(mesh_handle,
 728                             next_tvb, pinfo, tree);
 729                         next_tvb = tvb_new_subset_remaining(tvb, offset+5+mesh_header_len);
 730                         if (!dissector_try_uint(ethertype_subdissector_table,
 731                             etype, next_tvb, pinfo, tree))
 732                                 call_dissector(data_handle, next_tvb, pinfo,
 733                                     tree);
 734                 } else {
 735                         next_tvb = tvb_new_subset_remaining(tvb, offset+5);
 736                         call_dissector(data_handle, next_tvb, pinfo, tree);
 737                 }
 738                 break;
 739
 740         default:
 741                 /*
 742                  * Do we have information for this OUI?
 743                  */
 744                 oui_info = get_snap_oui_info(oui);
 745                 if (oui_info != NULL) {
 746                         /*
 747                          * Yes - use it.
 748                          */
 749                         hf = *oui_info->field_info->p_id;
 750                         subdissector_table = oui_info->table;
 751                 } else {
 752                         /*
 753                          * No, use hf_pid for the PID and just dissect
 754                          * the payload as data.
 755                          */
 756                         hf = hf_pid;
 757                         subdissector_table = NULL;
 758                 }
 759                 if (tree) {
 760                         proto_tree_add_uint(snap_tree, hf, tvb, offset+3, 2,
 761                             etype);
 762                 }
 763                 next_tvb = tvb_new_subset_remaining(tvb, offset+5);
 764                 if (XDLC_IS_INFORMATION(control)) {
 765                         if (subdissector_table != NULL) {
 766                                 /* do lookup with the subdissector table */
 767                                 if (dissector_try_uint(subdissector_table,
 768                                     etype, next_tvb, pinfo, tree))
 769                                         break;
 770                         }
 771                 }
 772                 call_dissector(data_handle, next_tvb, pinfo, tree);
 773                 break;
 774         }
 775 }
 776
 777 /*
 778  * Return the oui_info_t for the PID for a particular OUI value, or NULL
 779  * if there isn't one.
 780  */
 781 oui_info_t *
 782 get_snap_oui_info(guint32 oui)
 783 {
 784         if (oui_info_table != NULL) {
 785                 return g_hash_table_lookup(oui_info_table,
 786                     GUINT_TO_POINTER(oui));
 787         } else
 788                 return NULL;
 789 }
 790
 791 void
 792 proto_register_llc(void)
 793 {
 794         static struct true_false_string ig_bit = { "Group", "Individual" };
 795         static struct true_false_string cr_bit = { "Response", "Command" };
 796
 797         static hf_register_info hf[] = {
 798                 { &hf_llc_dsap,
 799                 { "DSAP",       "llc.dsap", FT_UINT8, BASE_HEX,
 800                         VALS(sap_vals), 0x0, "DSAP - 7 Most Significant Bits only", HFILL }},
 801
 802                 { &hf_llc_dsap_ig,
 803                 { "IG Bit",     "llc.dsap.ig", FT_BOOLEAN, BASE_NONE,
 804                         TFS(&ig_bit), 0x0, "Individual/Group - Least Significant Bit only", HFILL }},
 805
 806                 { &hf_llc_ssap,
 807                 { "SSAP", "llc.ssap", FT_UINT8, BASE_HEX,
 808                         VALS(sap_vals), 0x0, "SSAP - 7 Most Significant Bits only", HFILL }},
 809
 810                 { &hf_llc_ssap_cr,
 811                 { "CR Bit", "llc.ssap.cr", FT_BOOLEAN, BASE_NONE,
 812                         TFS(&cr_bit), 0x0, "Command/Response - Least Significant Bit only", HFILL }},
 813
 814                 { &hf_llc_ctrl,
 815                 { "Control", "llc.control", FT_UINT16, BASE_HEX,
 816                         NULL, 0x0, NULL, HFILL }},
 817
 818                 { &hf_llc_n_r,
 819                 { "N(R)", "llc.control.n_r", FT_UINT16, BASE_DEC,
 820                         NULL, XDLC_N_R_EXT_MASK, NULL, HFILL }},
 821
 822                 { &hf_llc_n_s,
 823                 { "N(S)", "llc.control.n_s", FT_UINT16, BASE_DEC,
 824                         NULL, XDLC_N_S_EXT_MASK, NULL, HFILL }},
 825
 826                 { &hf_llc_p,
 827                 { "Poll", "llc.control.p", FT_BOOLEAN, 8,
 828                         TFS(&tfs_set_notset), XDLC_P_F, NULL, HFILL }},
 829
 830                 { &hf_llc_p_ext,
 831                 { "Poll", "llc.control.p", FT_BOOLEAN, 16,
 832                         TFS(&tfs_set_notset), XDLC_P_F_EXT, NULL, HFILL }},
 833
 834                 { &hf_llc_f,
 835                 { "Final", "llc.control.f", FT_BOOLEAN, 8,
 836                         TFS(&tfs_set_notset), XDLC_P_F, NULL, HFILL }},
 837
 838                 { &hf_llc_f_ext,
 839                 { "Final", "llc.control.f", FT_BOOLEAN, 16,
 840                         TFS(&tfs_set_notset), XDLC_P_F_EXT, NULL, HFILL }},
 841
 842                 { &hf_llc_s_ftype,
 843                 { "Supervisory frame type", "llc.control.s_ftype", FT_UINT16, BASE_HEX,
 844                         VALS(stype_vals), XDLC_S_FTYPE_MASK, NULL, HFILL }},
 845
 846                 { &hf_llc_u_modifier_cmd,
 847                 { "Command", "llc.control.u_modifier_cmd", FT_UINT8, BASE_HEX,
 848                         VALS(modifier_vals_cmd), XDLC_U_MODIFIER_MASK, NULL, HFILL }},
 849
 850                 { &hf_llc_u_modifier_resp,
 851                 { "Response", "llc.control.u_modifier_resp", FT_UINT8, BASE_HEX,
 852                         VALS(modifier_vals_resp), XDLC_U_MODIFIER_MASK, NULL, HFILL }},
 853
 854                 { &hf_llc_ftype_i,
 855                 { "Frame type", "llc.control.ftype", FT_UINT16, BASE_HEX,
 856                         VALS(ftype_vals), XDLC_I_MASK, NULL, HFILL }},
 857
 858                 { &hf_llc_ftype_s_u,
 859                 { "Frame type", "llc.control.ftype", FT_UINT8, BASE_HEX,
 860                         VALS(ftype_vals), XDLC_S_U_MASK, NULL, HFILL }},
 861
 862                 { &hf_llc_ftype_s_u_ext,
 863                 { "Frame type", "llc.control.ftype", FT_UINT16, BASE_HEX,
 864                         VALS(ftype_vals), XDLC_S_U_MASK, NULL, HFILL }},
 865
 866                 /* registered here but handled in ethertype.c */
 867                 { &hf_llc_type,
 868                 { "Type", "llc.type", FT_UINT16, BASE_HEX,
 869                         VALS(etype_vals), 0x0, NULL, HFILL }},
 870
 871                 { &hf_llc_oui,
 872                 { "Organization Code",  "llc.oui", FT_UINT24, BASE_HEX,
 873                         VALS(oui_vals), 0x0, NULL, HFILL }},
 874
 875                 { &hf_llc_pid,
 876                 { "Protocol ID", "llc.pid", FT_UINT16, BASE_HEX,
 877                         NULL, 0x0, NULL, HFILL }}
 878         };
 879         static gint *ett[] = {
 880                 &ett_llc,
 881                 &ett_llc_ctrl
 882         };
 883
 884         proto_llc = proto_register_protocol("Logical-Link Control", "LLC", "llc");
 885         proto_register_field_array(proto_llc, hf, array_length(hf));
 886         proto_register_subtree_array(ett, array_length(ett));
 887
 888         /* subdissector code */
 889         dsap_subdissector_table = register_dissector_table("llc.dsap",
 890           "LLC SAP", FT_UINT8, BASE_HEX);
 891         xid_subdissector_table = register_dissector_table("llc.xid_dsap",
 892           "LLC XID SAP", FT_UINT8, BASE_HEX);
 893
 894         register_dissector("llc", dissect_llc, proto_llc);
 895 }
 896
 897 void
 898 proto_register_basicxid(void)
 899 {
 900         static hf_register_info hf[] = {
 901                 { &hf_llc_xid_format,
 902                 { "XID Format", "basicxid.llc.xid.format", FT_UINT8, BASE_HEX,
 903                         VALS(format_vals), 0x0, NULL, HFILL }},
 904
 905                 { &hf_llc_xid_types,
 906                 { "LLC Types/Classes", "basicxid.llc.xid.types", FT_UINT8, BASE_HEX,
 907                         VALS(type_vals), 0x0, NULL, HFILL }},
 908
 909                 { &hf_llc_xid_wsize,
 910                 { "Receive Window Size", "basicxid.llc.xid.wsize", FT_UINT8, BASE_DEC,
 911                         NULL, 0x0, NULL, HFILL }}
 912         };
 913         static gint *ett[] = {
 914                 &ett_llc_basicxid
 915         };
 916
 917         proto_basicxid = proto_register_protocol("Logical-Link Control Basic Format XID", "Basic Format XID", "basicxid");
 918         proto_register_field_array(proto_basicxid, hf, array_length(hf));
 919         proto_register_subtree_array(ett, array_length(ett));
 920
 921         register_dissector("basicxid", dissect_basicxid, proto_basicxid);
 922 }
 923
 924 static void
 925 register_hf(gpointer key _U_, gpointer value, gpointer user_data _U_)
 926 {
 927         oui_info_t *info = value;
 928
 929         proto_register_field_array(proto_llc, info->field_info, 1);
 930 }
 931
 932 void
 933 proto_reg_handoff_llc(void)
 934 {
 935         dissector_handle_t llc_handle;
 936
 937         /*
 938          * Get handles for the BPDU, Ethernet, FDDI, Token Ring and
 939          * Turbocell dissectors.
 940          */
 941         bpdu_handle = find_dissector("bpdu");
 942         eth_withoutfcs_handle = find_dissector("eth_withoutfcs");
 943         eth_withfcs_handle = find_dissector("eth_withfcs");
 944         fddi_handle = find_dissector("fddi");
 945         tr_handle = find_dissector("tr");
 946         turbo_handle = find_dissector("turbocell");
 947         mesh_handle = find_dissector("mesh");
 948         data_handle = find_dissector("data");
 949
 950         /*
 951          * Get the Ethertype dissector table.
 952          */
 953         ethertype_subdissector_table = find_dissector_table("ethertype");
 954         hpteam_subdissector_table = find_dissector_table("llc.hpteam_pid");
 955
 956         llc_handle = find_dissector("llc");
 957         dissector_add_uint("wtap_encap", WTAP_ENCAP_ATM_RFC1483, llc_handle);
 958         dissector_add_uint("sll.ltype", LINUX_SLL_P_802_2, llc_handle);
 959         /* RFC 2043 */
 960         dissector_add_uint("ppp.protocol", PPP_LLC, llc_handle);
 961         /* RFC 2353 */
 962         dissector_add_uint("udp.port", UDP_PORT_LLC1, llc_handle);
 963         dissector_add_uint("udp.port", UDP_PORT_LLC2, llc_handle);
 964         dissector_add_uint("udp.port", UDP_PORT_LLC3, llc_handle);
 965         dissector_add_uint("udp.port", UDP_PORT_LLC4, llc_handle);
 966         dissector_add_uint("udp.port", UDP_PORT_LLC5, llc_handle);
 967         /* IP-over-FC when we have the full FC frame */
 968         dissector_add_uint("fc.ftype", FC_FTYPE_IP, llc_handle);
 969
 970         /*
 971          * BACNET-over-ARCNET is really BACNET-over-802.2 LLC-over-ARCNET,
 972          * apparently.
 973          */
 974         dissector_add_uint("arcnet.protocol_id", ARCNET_PROTO_BACNET, llc_handle);
 975         dissector_add_uint("ethertype", ETHERTYPE_JUMBO_LLC, llc_handle);
 976
 977         /*
 978          * Register all the fields for PIDs for various OUIs.
 979          */
 980         if (oui_info_table != NULL)
 981                 g_hash_table_foreach(oui_info_table, register_hf, NULL);
 982 }