epan/dissectors/packet-mrp-mmrp.c

   1 /* packet-mrp_mmrp.c
   2  * Routines for MMRP (MRP Multiple Mac Registration Protocol) dissection
   3  * Copyright 2011, Johannes Jochen <johannes.jochen[AT]belden.com>
   4  *
   5  *
   6  * Based on the code from packet-mrp-msrp.c (MSRP) from
   7  * Torrey Atcitty <tatcitty[AT]harman.com> and Craig Gunther <craig.gunther[AT]harman.com>
   8  * Copyright 2010
   9  *
  10  * $Id$
  11  *
  12  * Wireshark - Network traffic analyzer
  13  * By Gerald Combs <gerald[AT]wireshark.org>
  14  * Copyright 1998 Gerald Combs
  15  *
  16  * This program is free software; you can redistribute it and/or
  17  * modify it under the terms of the GNU General Public License
  18  * as published by the Free Software Foundation; either version 2
  19  * of the License, or (at your option) any later version.
  20  *
  21  * This program is distributed in the hope that it will be useful,
  22  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  23  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  24  * GNU General Public License for more details.
  25  *
  26  * You should have received a copy of the GNU General Public License
  27  * along with this program; if not, write to the Free Software
  28  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  29  *
  30  * The MMRP Protocol specification can be found at the following:
  31  * http://standards.ieee.org/about/get/802/802.1.html
  32  *
  33  */
  34
  35 #include "config.h"
  36
  37 #include <epan/packet.h>
  38 #include <epan/etypes.h>
  39
  40 /* MMRP End Mark Sequence */
  41 #define MMRP_END_MARK       0x0000
  42
  43 /**********************************************************/
  44 /* Offsets of fields within an MMRP packet                */
  45 /**********************************************************/
  46 #define MMRP_PROTOCOL_VERSION_OFFSET        0
  47
  48 /* Next comes the MMRP Message group */
  49 #define MMRP_MESSAGE_GROUP_OFFSET          (MMRP_PROTOCOL_VERSION_OFFSET + 1) /* Message is a group of fields */
  50 #define MMRP_ATTRIBUTE_TYPE_OFFSET         (MMRP_MESSAGE_GROUP_OFFSET)
  51 #define MMRP_ATTRIBUTE_LENGTH_OFFSET       (MMRP_ATTRIBUTE_TYPE_OFFSET + 1)
  52
  53 /* Next comes the MMRP AttributeList group */
  54 #define MMRP_ATTRIBUTE_LIST_GROUP_OFFSET   (MMRP_ATTRIBUTE_LENGTH_OFFSET + 1) /* AttributeList is a group of fields */
  55
  56 /* Next comes the MMRP VectorAttribute group */
  57 #define MMRP_VECTOR_ATTRIBUTE_GROUP_OFFSET (MMRP_ATTRIBUTE_LIST_GROUP_OFFSET) /* VectorAttribute is a group of fields */
  58 #define MMRP_VECTOR_HEADER_OFFSET          (MMRP_VECTOR_ATTRIBUTE_GROUP_OFFSET) /* contains the following two fields */
  59 #define MMRP_LEAVE_ALL_EVENT_OFFSET        (MMRP_VECTOR_HEADER_OFFSET)
  60 #define MMRP_LEAVE_ALL_EVENT_MASK           0xE000
  61 #define MMRP_NUMBER_OF_VALUES_OFFSET       (MMRP_VECTOR_HEADER_OFFSET)
  62 #define MMRP_NUMBER_OF_VALUES_MASK          0x1fff
  63
  64 /* Next comes the MMRP FirstValue group */
  65 #define MMRP_FIRST_VALUE_GROUP_OFFSET      (MMRP_VECTOR_HEADER_OFFSET + 2) /* FirstValue is a group of fields */
  66
  67 #define MMRP_SERVICE_THREE_PACKED_OFFSET   (MMRP_FIRST_VALUE_GROUP_OFFSET + 1)
  68 #define MMRP_MAC_THREE_PACKED_OFFSET       (MMRP_FIRST_VALUE_GROUP_OFFSET + 6)
  69
  70 /**********************************************************/
  71 /* Valid field contents                                   */
  72 /**********************************************************/
  73
  74 /* Attribute Type definitions */
  75 #define MMRP_ATTRIBUTE_TYPE_SERVICE   0x01
  76 #define MMRP_ATTRIBUTE_TYPE_MAC       0x02
  77 static const value_string attribute_type_vals[] = {
  78     { MMRP_ATTRIBUTE_TYPE_SERVICE, "Service Requirement" },
  79     { MMRP_ATTRIBUTE_TYPE_MAC,    "MAC" },
  80     { 0,                                    NULL }
  81 };
  82
  83 /* Leave All Event definitions */
  84 #define MMRP_NULLLEAVEALL   0
  85 #define MMRP_LEAVEALL       1
  86 static const value_string leave_all_vals[] = {
  87     { MMRP_NULLLEAVEALL, "Null" },
  88     { MMRP_LEAVEALL,     "Leave All" },
  89     { 0,                 NULL }
  90 };
  91
  92 /* Three Packed Event definitions */
  93 static const value_string three_packed_vals[] = {
  94     { 0, "New" },
  95     { 1, "JoinIn" },
  96     { 2, "In" },
  97     { 3, "JoinMt" },
  98     { 4, "Mt" },
  99     { 5, "Lv" },
 100     { 0, NULL }
 101 };
 102
 103 /**********************************************************/
 104 /* Initialize the protocol and registered fields          */
 105 /**********************************************************/
 106 static int proto_mmrp = -1;
 107 static int hf_mmrp_proto_id = -1;
 108 static int hf_mmrp_message = -1; /* Message is a group of fields */
 109 static int hf_mmrp_attribute_type = -1;
 110 static int hf_mmrp_attribute_length = -1;
 111 static int hf_mmrp_attribute_list = -1; /* AttributeList is a group of fields */
 112 static int hf_mmrp_vector_attribute = -1; /* VectorAttribute is a group of fields */
 113
 114 /* The following VectorHeader contains the LeaveAllEvent and NumberOfValues */
 115 static int hf_mmrp_vector_header = -1;
 116 static int hf_mmrp_leave_all_event = -1;
 117 static int hf_mmrp_number_of_values = -1;
 118 static gint ett_vector_header = -1;
 119 static const int *vector_header_fields[] = {
 120     &hf_mmrp_leave_all_event,
 121     &hf_mmrp_number_of_values,
 122     NULL
 123 };
 124
 125 static int hf_mmrp_first_value = -1; /* FirstValue is a group of fields */
 126
 127 static int hf_mmrp_three_packed_event = -1;
 128
 129 static int hf_mmrp_end_mark = -1;
 130
 131 /* Initialize the subtree pointers */
 132 static gint ett_mmrp = -1;
 133 static gint ett_msg = -1;
 134 static gint ett_attr_list = -1;
 135 static gint ett_vect_attr = -1;
 136 static gint ett_first_value = -1;
 137
 138
 139
 140 /**********************************************************/
 141 /* Dissector starts here                                  */
 142 /**********************************************************/
 143
 144 /* dissect_mmrp_common1 (called from dissect_mmrp)
 145  *
 146  * dissect the following fields which are common to all MMRP attributes:
 147  *   Attribute Type
 148  *   Attribute Length
 149  *   Attribute List Length
 150  */
 151 static void
 152 dissect_mmrp_common1(proto_tree *msg_tree, tvbuff_t *tvb, int msg_offset)
 153 {
 154     proto_tree_add_item(msg_tree, hf_mmrp_attribute_type, tvb,
 155                         MMRP_ATTRIBUTE_TYPE_OFFSET + msg_offset, 1, ENC_BIG_ENDIAN);
 156     proto_tree_add_item(msg_tree, hf_mmrp_attribute_length, tvb,
 157                         MMRP_ATTRIBUTE_LENGTH_OFFSET + msg_offset, 1, ENC_BIG_ENDIAN);
 158 }
 159
 160
 161 /* dissect_mmrp_common2 (called from dissect_mmrp)
 162  *
 163  * dissect the following fields which are common to all MMRP attributes:
 164  *   Leave All Event
 165  *   Number of Values fields
 166  */
 167 static void
 168 dissect_mmrp_common2(proto_tree *vect_attr_tree, tvbuff_t *tvb, int msg_offset)
 169 {
 170     proto_tree_add_bitmask(vect_attr_tree, tvb, MMRP_VECTOR_HEADER_OFFSET + msg_offset,
 171                            hf_mmrp_vector_header, ett_vector_header, vector_header_fields, ENC_BIG_ENDIAN);
 172 }
 173
 174 /* dissect_mmrp_three_packed_event (called from dissect_mmrp)
 175  *
 176  * dissect one or more ThreePackedEvents
 177  */
 178 static guint
 179 dissect_mmrp_three_packed_event(proto_tree *vect_attr_tree, tvbuff_t *tvb, guint offset, guint16 number_of_values)
 180 {
 181     guint counter;
 182
 183     for ( counter = 0; counter < number_of_values; ) {
 184         guint8 value;
 185         guint8 three_packed_event[3];
 186
 187         value = tvb_get_guint8(tvb, offset);
 188         three_packed_event[0] = value / 36;
 189         value -= 36 * three_packed_event[0];
 190         three_packed_event[1] = value / 6;
 191         value -=  6 * three_packed_event[1];
 192         three_packed_event[2] = value;
 193
 194         proto_tree_add_uint(vect_attr_tree, hf_mmrp_three_packed_event, tvb, offset, sizeof(guint8),
 195                             three_packed_event[0]);
 196         counter++;
 197         if ( counter < number_of_values ) {
 198             proto_tree_add_uint(vect_attr_tree, hf_mmrp_three_packed_event, tvb, offset, sizeof(guint8),
 199                                 three_packed_event[1]);
 200             counter++;
 201         }
 202         if ( counter < number_of_values ) {
 203             proto_tree_add_uint(vect_attr_tree, hf_mmrp_three_packed_event, tvb, offset, sizeof(guint8),
 204                                 three_packed_event[2]);
 205             counter++;
 206         }
 207
 208         offset++;
 209     }
 210     return( offset );
 211 }
 212
 213 /* dissect_main
 214  *
 215  * main dissect function that calls the other functions listed above as necessary
 216  */
 217 static void
 218 dissect_mmrp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 219 {
 220     /* Set up structures needed to add the protocol subtrees and manage them */
 221     proto_item *ti, *msg_ti, *attr_list_ti, *vect_attr_ti;
 222     proto_tree *mmrp_tree, *msg_tree, *attr_list_tree, *vect_attr_tree;
 223
 224     /* Make entries in Protocol column and Info column on summary display */
 225     col_set_str(pinfo->cinfo, COL_PROTOCOL, "MRP-MMRP");
 226
 227     col_set_str(pinfo->cinfo, COL_INFO, "Multiple Mac Registration Protocol");
 228
 229     if (tree) {
 230         guint8 attribute_type;
 231         guint8 attribute_length;
 232         guint16 number_of_values;
 233         guint offset = 0;
 234         int vect_attr_len;
 235         int msg_offset;  /* Use when handling multiple messages.  This points to current msg being decoded. */
 236         int vect_offset; /* Use when handling multiple vector attributes.  This points to the current vector attribute being decoded. */
 237
 238         ti = proto_tree_add_item(tree, proto_mmrp, tvb, 0, -1, ENC_NA);
 239         mmrp_tree = proto_item_add_subtree(ti, ett_mmrp);
 240
 241         proto_tree_add_item(mmrp_tree, hf_mmrp_proto_id, tvb, MMRP_PROTOCOL_VERSION_OFFSET, 1, ENC_BIG_ENDIAN);
 242
 243         /* MMRP supports multiple MRP Messages per frame.  Handle those Messages in
 244          * the following while() loop. You will know you are at the end of the list
 245          * of messages when the EndMark (0x0000) is encountered instead of an
 246          * Attribute Type and Attribute Length (guaranteed to not be 0x0000).
 247          */
 248         msg_offset = 0;
 249         while (tvb_get_ntohs(tvb, MMRP_ATTRIBUTE_TYPE_OFFSET + msg_offset) != MMRP_END_MARK) {
 250
 251             attribute_type = tvb_get_guint8(tvb, MMRP_ATTRIBUTE_TYPE_OFFSET + msg_offset);
 252             attribute_length = tvb_get_guint8(tvb, MMRP_ATTRIBUTE_LENGTH_OFFSET + msg_offset);
 253
 254             /* MMRP Message is a group of fields
 255              *
 256              * Contains AttributeType (1 byte)
 257              *        + AttributeLength (1 byte)
 258              *        + AttributeList (AttributeListLength bytes)
 259             *        bytes of data
 260             */
 261             msg_ti = proto_tree_add_item(mmrp_tree, hf_mmrp_message, tvb,
 262                                          MMRP_MESSAGE_GROUP_OFFSET + msg_offset,
 263                                          -1, ENC_NA);
 264             msg_tree = proto_item_add_subtree(msg_ti, ett_msg);
 265
 266             /* Append AttributeType description to the end of the "Message" heading */
 267             proto_item_append_text(msg_tree, ": %s (%d)",
 268                                    val_to_str_const(attribute_type, attribute_type_vals, "<Unknown>"),
 269                                    attribute_type);
 270
 271             dissect_mmrp_common1(msg_tree, tvb, msg_offset);
 272
 273             /* MMRP AttributeList is a group of fields
 274              *
 275              * Contains AttributeListLength bytes of data NOT
 276              */
 277             attr_list_ti = proto_tree_add_item(msg_tree, hf_mmrp_attribute_list, tvb,
 278                                                MMRP_ATTRIBUTE_LIST_GROUP_OFFSET + msg_offset,
 279                                                -1, ENC_NA);
 280             attr_list_tree = proto_item_add_subtree(attr_list_ti, ett_attr_list);
 281
 282
 283             /* MMRP supports multiple MRP Vector Attributes per Attribute List.  Handle those
 284              * Vector Attributes in the following while() loop. You will know you are at the
 285              * end of the list of Vector Attributes when the EndMark (0x0000) is encountered
 286              * instead of a Vector Header (guaranteed to not be 0x0000).
 287              */
 288             vect_offset = 0;
 289             while (tvb_get_ntohs(tvb, MMRP_VECTOR_HEADER_OFFSET + msg_offset + vect_offset) != MMRP_END_MARK) {
 290                 /* MMRP VectorAttribute is a group of fields
 291                  *
 292                  * Contains VectorHeader (2 bytes)
 293                  *        + FirstValue (AttributeLength bytes)
 294                  *        + VectorThreePacked (NumberOfValues @ 3/vector bytes)
 295                  *        + VectorFourPacked (NumberOfValues @ 4/vector bytes only for Listener attributes)
 296                  *        bytes of data
 297                  */
 298                 number_of_values = tvb_get_ntohs(tvb, MMRP_NUMBER_OF_VALUES_OFFSET + msg_offset + vect_offset)
 299                                    & MMRP_NUMBER_OF_VALUES_MASK;
 300
 301                 vect_attr_len = 2 + attribute_length + (number_of_values + 2)/3; /* stores 3 values per byte */
 302
 303                 vect_attr_ti = proto_tree_add_item(attr_list_tree, hf_mmrp_vector_attribute, tvb,
 304                                                    MMRP_VECTOR_ATTRIBUTE_GROUP_OFFSET + msg_offset + vect_offset,
 305                                                    vect_attr_len, ENC_NA);
 306
 307                 vect_attr_tree = proto_item_add_subtree(vect_attr_ti, ett_vect_attr);
 308
 309                 dissect_mmrp_common2(vect_attr_tree, tvb, msg_offset + vect_offset);
 310
 311                 if (attribute_type == MMRP_ATTRIBUTE_TYPE_MAC) {
 312                     /* MMRP FirstValue is a Mac Adress*/
 313                     proto_tree_add_item(vect_attr_tree, hf_mmrp_first_value, tvb,
 314                                         MMRP_FIRST_VALUE_GROUP_OFFSET + msg_offset + vect_offset,
 315                                         attribute_length, ENC_NA);
 316                     /* Decode three packed events. */
 317                     offset = dissect_mmrp_three_packed_event(vect_attr_tree, tvb,
 318                                                              MMRP_MAC_THREE_PACKED_OFFSET + msg_offset + vect_offset,
 319                                                              number_of_values);
 320
 321                 }
 322                 else if (attribute_type == MMRP_ATTRIBUTE_TYPE_SERVICE) {
 323                     /* MMRP Service Requierment*/
 324                     proto_tree_add_item(vect_attr_tree, hf_mmrp_first_value, tvb,
 325                                         MMRP_FIRST_VALUE_GROUP_OFFSET + msg_offset + vect_offset,
 326                                         attribute_length, ENC_NA);
 327                     offset = dissect_mmrp_three_packed_event(vect_attr_tree, tvb,
 328                                                              MMRP_MAC_THREE_PACKED_OFFSET + msg_offset + vect_offset,
 329                                                              number_of_values);
 330
 331                 }
 332
 333                 vect_offset += vect_attr_len; /* Move to next Vector Attribute, if there is one */
 334             } /* Multiple VectorAttribute while() */
 335
 336             proto_tree_add_item(attr_list_tree, hf_mmrp_end_mark, tvb, offset, 2, ENC_NA); /* VectorAttribute EndMark */
 337
 338             proto_item_set_len(attr_list_ti, vect_offset); /*without an endmark*/
 339             msg_offset += vect_offset + 2; /*  + endmark; Move to next Message, if there is one */
 340             proto_item_set_len(msg_ti, vect_offset + 2); /*length of message*/
 341
 342         } /* Multiple Message while() */
 343
 344         proto_tree_add_item(mmrp_tree, hf_mmrp_end_mark, tvb, offset+2, 2, ENC_NA); /* Message EndMark */
 345     }
 346 }
 347
 348
 349 /* Register the protocol with Wireshark */
 350 void
 351 proto_register_mrp_mmrp(void)
 352 {
 353     static hf_register_info hf[] = {
 354         { &hf_mmrp_proto_id,
 355             { "Protocol Version",      "mrp-mmrp.protocol_version",
 356               FT_UINT8,  BASE_DEC, NULL, 0x0, NULL, HFILL }
 357         },
 358         { &hf_mmrp_message, /* Message is a group of fields */
 359             { "Message",               "mrp-mmrp.message",
 360               FT_NONE,  BASE_NONE, NULL, 0x0, NULL, HFILL }
 361         },
 362         { &hf_mmrp_attribute_type,
 363             { "Attribute Type",        "mrp-mmrp.attribute_type",
 364               FT_UINT8,  BASE_DEC, VALS(attribute_type_vals), 0x0, NULL, HFILL }
 365         },
 366         { &hf_mmrp_attribute_length,
 367             { "Attribute Length",      "mrp-mmrp.attribute_length",
 368               FT_UINT8,  BASE_DEC, NULL, 0x0, NULL, HFILL }
 369         },
 370         { &hf_mmrp_attribute_list, /* AttributeList is a group of fields */
 371             { "Attribute List",        "mrp-mmrp.attribute_list",
 372               FT_NONE,  BASE_NONE, NULL, 0x0, NULL, HFILL }
 373         },
 374         { &hf_mmrp_vector_attribute, /* VectorAttribute is a group of fields */
 375             { "Vector Attribute",      "mrp-mmrp.vector_attribute",
 376               FT_NONE,  BASE_NONE, NULL, 0x0, NULL, HFILL }
 377         },
 378         { &hf_mmrp_vector_header,
 379             { "Vector Header",         "mrp-mmrp.vector_header",
 380               FT_UINT16, BASE_HEX, NULL, 0x0, NULL, HFILL }
 381         },
 382         { &hf_mmrp_leave_all_event,
 383             { "Leave All Event",       "mrp-mmrp.leave_all_event",
 384               FT_UINT16, BASE_DEC, VALS(leave_all_vals), MMRP_LEAVE_ALL_EVENT_MASK, NULL, HFILL }
 385         },
 386         { &hf_mmrp_number_of_values,
 387             { "Number of Values",      "mrp-mmrp.number_of_values",
 388               FT_UINT16, BASE_DEC, NULL, MMRP_NUMBER_OF_VALUES_MASK, NULL, HFILL }
 389         },
 390         { &hf_mmrp_first_value, /* FirstValue is a group of fields */
 391             { "First Value",           "mrp-mmrp.first_value",
 392               FT_NONE,  BASE_NONE, NULL, 0x0, NULL, HFILL }
 393         },
 394         { &hf_mmrp_three_packed_event,
 395             { "Attribute Event",       "mrp-msrp.three_packed_event",
 396               FT_UINT8, BASE_DEC,  VALS(three_packed_vals), 0x0, NULL, HFILL }
 397         },
 398         { &hf_mmrp_end_mark,
 399             { "End Mark",              "mrp-mmrp.end_mark",
 400               FT_UINT16, BASE_HEX, NULL, 0x0, NULL, HFILL }
 401         },
 402     };
 403
 404     /* Setup protocol subtree array */
 405     static gint *ett[] = {
 406         &ett_mmrp,
 407         &ett_msg,
 408         &ett_attr_list,
 409         &ett_vect_attr,
 410         &ett_vector_header,
 411         &ett_first_value
 412     };
 413
 414     /* Register the protocol name and description */
 415     proto_mmrp = proto_register_protocol("Multiple Mac Registration Protocol",
 416                                          "MRP-MMRP", "mrp-mmrp");
 417
 418     /* Required function calls to register the header fields and subtrees used */
 419     proto_register_field_array(proto_mmrp, hf, array_length(hf));
 420     proto_register_subtree_array(ett, array_length(ett));
 421 }
 422
 423 void
 424 proto_reg_handoff_mrp_mmrp(void)
 425 {
 426     dissector_handle_t mmrp_handle;
 427
 428     mmrp_handle = create_dissector_handle(dissect_mmrp, proto_mmrp);
 429     dissector_add_uint("ethertype", ETHERTYPE_MMRP, mmrp_handle);
 430 }