epan/dissectors/packet-mrp-mvrp.c

   1 /* packet-mrp_mvrp.c
   2  * Routines for MVRP (MRP Multiple VLAN Registration Protocol) dissection
   3  * Copyright 2011, Pascal Levesque <plevesque[AT]orthogone.ca>
   4  *
   5  *
   6  * Based on the code from packet-mrp-mmrp.c (MMRP) from
   7  * Johannes Jochen <johannes.jochen[AT]belden.com>
   8  * Copyright 2011
   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 MVRP 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 /* MVRP End Mark Sequence */
  41 #define MVRP_END_MARK       0x0000
  42
  43 /**********************************************************/
  44 /* Offsets of fields within an MVRP packet                */
  45 /**********************************************************/
  46 #define MVRP_PROTOCOL_VERSION_OFFSET        0
  47
  48 /* Next comes the MVRP Message group */
  49 #define MVRP_MESSAGE_GROUP_OFFSET          (MVRP_PROTOCOL_VERSION_OFFSET + 1) /* Message is a group of fields */
  50 #define MVRP_ATTRIBUTE_TYPE_OFFSET         (MVRP_MESSAGE_GROUP_OFFSET)
  51 #define MVRP_ATTRIBUTE_LENGTH_OFFSET       (MVRP_ATTRIBUTE_TYPE_OFFSET + 1)
  52
  53 /* Next comes the MVRP AttributeList group */
  54 #define MVRP_ATTRIBUTE_LIST_GROUP_OFFSET   (MVRP_ATTRIBUTE_LENGTH_OFFSET + 1) /* AttributeList is a group of fields */
  55
  56 /* Next comes the MVRP VectorAttribute group */
  57 #define MVRP_VECTOR_ATTRIBUTE_GROUP_OFFSET (MVRP_ATTRIBUTE_LIST_GROUP_OFFSET) /* VectorAttribute is a group of fields */
  58 #define MVRP_VECTOR_HEADER_OFFSET          (MVRP_VECTOR_ATTRIBUTE_GROUP_OFFSET) /* contains the following two fields */
  59 #define MVRP_LEAVE_ALL_EVENT_OFFSET        (MVRP_VECTOR_HEADER_OFFSET)
  60 #define MVRP_LEAVE_ALL_EVENT_MASK           0xE000
  61 #define MVRP_NUMBER_OF_VALUES_OFFSET       (MVRP_VECTOR_HEADER_OFFSET)
  62 #define MVRP_NUMBER_OF_VALUES_MASK          0x1fff
  63
  64 /* Next comes the MVRP FirstValue group */
  65 #define MVRP_FIRST_VALUE_GROUP_OFFSET      (MVRP_VECTOR_HEADER_OFFSET + 2) /* FirstValue is a group of fields */
  66
  67 #define MVRP_VID_THREE_PACKED_OFFSET       (MVRP_FIRST_VALUE_GROUP_OFFSET + 2)
  68
  69 /**********************************************************/
  70 /* Valid field contents                                   */
  71 /**********************************************************/
  72
  73 /* Attribute Type definitions */
  74 #define MVRP_ATTRIBUTE_TYPE_VID       0x01
  75 static const value_string attribute_type_vals[] = {
  76     { MVRP_ATTRIBUTE_TYPE_VID, "VLAN Identifier" },
  77     { 0,                                    NULL }
  78 };
  79
  80 /* Leave All Event definitions */
  81 #define MVRP_NULLLEAVEALL   0
  82 #define MVRP_LEAVEALL       1
  83 static const value_string leave_all_vals[] = {
  84     { MVRP_NULLLEAVEALL, "Null" },
  85     { MVRP_LEAVEALL,     "Leave All" },
  86     { 0,                 NULL }
  87 };
  88
  89 /* Three Packed Event definitions */
  90 static const value_string three_packed_vals[] = {
  91     { 0, "New" },
  92     { 1, "JoinIn" },
  93     { 2, "In" },
  94     { 3, "JoinMt" },
  95     { 4, "Mt" },
  96     { 5, "Lv" },
  97     { 0, NULL }
  98 };
  99
 100 /**********************************************************/
 101 /* Initialize the protocol and registered fields          */
 102 /**********************************************************/
 103 static int proto_mvrp = -1;
 104 static int hf_mvrp_proto_id = -1;
 105 static int hf_mvrp_message = -1; /* Message is a group of fields */
 106 static int hf_mvrp_attribute_type = -1;
 107 static int hf_mvrp_attribute_length = -1;
 108 static int hf_mvrp_attribute_list = -1; /* AttributeList is a group of fields */
 109 static int hf_mvrp_vector_attribute = -1; /* VectorAttribute is a group of fields */
 110
 111 /* The following VectorHeader contains the LeaveAllEvent and NumberOfValues */
 112 static int hf_mvrp_vector_header = -1;
 113 static int hf_mvrp_leave_all_event = -1;
 114 static int hf_mvrp_number_of_values = -1;
 115 static gint ett_vector_header = -1;
 116 static const int *vector_header_fields[] = {
 117     &hf_mvrp_leave_all_event,
 118     &hf_mvrp_number_of_values,
 119     NULL
 120 };
 121
 122 static int hf_mvrp_first_value = -1; /* FirstValue is a group of fields */
 123 static int hf_mvrp_vid = -1;
 124 static int hf_mvrp_three_packed_event = -1;
 125
 126 static int hf_mvrp_end_mark = -1;
 127
 128 /* Initialize the subtree pointers */
 129 static gint ett_mvrp = -1;
 130 static gint ett_msg = -1;
 131 static gint ett_attr_list = -1;
 132 static gint ett_vect_attr = -1;
 133 static gint ett_first_value = -1;
 134
 135
 136
 137 /**********************************************************/
 138 /* Dissector starts here                                  */
 139 /**********************************************************/
 140
 141 /* dissect_mvrp_common1 (called from dissect_mvrp)
 142  *
 143  * dissect the following fields which are common to all MVRP attributes:
 144  *   Attribute Type
 145  *   Attribute Length
 146  *   Attribute List Length
 147  */
 148 static void
 149 dissect_mvrp_common1(proto_tree *msg_tree, tvbuff_t *tvb, int msg_offset)
 150 {
 151     proto_tree_add_item(msg_tree, hf_mvrp_attribute_type, tvb,
 152                         MVRP_ATTRIBUTE_TYPE_OFFSET + msg_offset, 1, ENC_BIG_ENDIAN);
 153     proto_tree_add_item(msg_tree, hf_mvrp_attribute_length, tvb,
 154                         MVRP_ATTRIBUTE_LENGTH_OFFSET + msg_offset, 1, ENC_BIG_ENDIAN);
 155 }
 156
 157
 158 /* dissect_mvrp_common2 (called from dissect_mvrp)
 159  *
 160  * dissect the following fields which are common to all MVRP attributes:
 161  *   Leave All Event
 162  *   Number of Values fields
 163  */
 164 static void
 165 dissect_mvrp_common2(proto_tree *vect_attr_tree, tvbuff_t *tvb, int msg_offset)
 166 {
 167     proto_tree_add_bitmask(vect_attr_tree, tvb, MVRP_VECTOR_HEADER_OFFSET + msg_offset,
 168                            hf_mvrp_vector_header, ett_vector_header, vector_header_fields, ENC_BIG_ENDIAN);
 169 }
 170
 171 /* dissect_mvrp_three_packed_event (called from dissect_mvrp)
 172  *
 173  * dissect one or more ThreePackedEvents
 174  */
 175 static guint
 176 dissect_mvrp_three_packed_event(proto_tree *vect_attr_tree, tvbuff_t *tvb, guint offset, guint16 number_of_values)
 177 {
 178     guint counter;
 179
 180     for ( counter = 0; counter < number_of_values; ) {
 181         guint8 value;
 182         guint8 three_packed_event[3];
 183
 184         value = tvb_get_guint8(tvb, offset);
 185         three_packed_event[0] = value / 36;
 186         value -= 36 * three_packed_event[0];
 187         three_packed_event[1] = value / 6;
 188         value -=  6 * three_packed_event[1];
 189         three_packed_event[2] = value;
 190
 191         proto_tree_add_uint(vect_attr_tree, hf_mvrp_three_packed_event, tvb, offset, sizeof(guint8),
 192                             three_packed_event[0]);
 193         counter++;
 194         if ( counter < number_of_values ) {
 195             proto_tree_add_uint(vect_attr_tree, hf_mvrp_three_packed_event, tvb, offset, sizeof(guint8),
 196                                 three_packed_event[1]);
 197             counter++;
 198         }
 199         if ( counter < number_of_values ) {
 200             proto_tree_add_uint(vect_attr_tree, hf_mvrp_three_packed_event, tvb, offset, sizeof(guint8),
 201                                 three_packed_event[2]);
 202             counter++;
 203         }
 204
 205         offset++;
 206     }
 207     return( offset );
 208 }
 209
 210 /* dissect_main
 211  *
 212  * main dissect function that calls the other functions listed above as necessary
 213  */
 214 static void
 215 dissect_mvrp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 216 {
 217     /* Set up structures needed to add the protocol subtrees and manage them */
 218     proto_item *ti, *msg_ti, *attr_list_ti, *vect_attr_ti, *first_value_ti;
 219     proto_tree *mvrp_tree, *msg_tree, *attr_list_tree, *vect_attr_tree, *first_value_tree;
 220
 221     /* Make entries in Protocol column and Info column on summary display */
 222     col_set_str(pinfo->cinfo, COL_PROTOCOL, "MRP-MVRP");
 223
 224     col_set_str(pinfo->cinfo, COL_INFO, "Multiple VLAN Registration Protocol");
 225
 226     if (tree) {
 227         guint8 attribute_type;
 228         guint8 attribute_length;
 229         guint16 number_of_values;
 230         guint offset = 0;
 231         int vect_attr_len;
 232         int msg_offset;  /* Use when handling multiple messages.  This points to current msg being decoded. */
 233         int vect_offset; /* Use when handling multiple vector attributes.  This points to the current vector attribute being decoded. */
 234
 235         ti = proto_tree_add_item(tree, proto_mvrp, tvb, 0, -1, ENC_NA);
 236         mvrp_tree = proto_item_add_subtree(ti, ett_mvrp);
 237
 238         proto_tree_add_item(mvrp_tree, hf_mvrp_proto_id, tvb, MVRP_PROTOCOL_VERSION_OFFSET, 1, ENC_BIG_ENDIAN);
 239
 240         /* MVRP supports multiple MRP Messages per frame.  Handle those Messages in
 241          * the following while() loop. You will know you are at the end of the list
 242          * of messages when the EndMark (0x0000) is encountered instead of an
 243          * Attribute Type and Attribute Length (guaranteed to not be 0x0000).
 244          */
 245         msg_offset = 0;
 246         while (tvb_get_ntohs(tvb, MVRP_ATTRIBUTE_TYPE_OFFSET + msg_offset) != MVRP_END_MARK) {
 247
 248             attribute_type = tvb_get_guint8(tvb, MVRP_ATTRIBUTE_TYPE_OFFSET + msg_offset);
 249             attribute_length = tvb_get_guint8(tvb, MVRP_ATTRIBUTE_LENGTH_OFFSET + msg_offset);
 250
 251             /* MVRP Message is a group of fields
 252              *
 253              * Contains AttributeType (1 byte)
 254              *        + AttributeLength (1 byte)
 255              *        + AttributeList (AttributeListLength bytes)
 256             *        bytes of data
 257             */
 258             msg_ti = proto_tree_add_item(mvrp_tree, hf_mvrp_message, tvb,
 259                                          MVRP_MESSAGE_GROUP_OFFSET + msg_offset,
 260                                          -1, ENC_NA);
 261             msg_tree = proto_item_add_subtree(msg_ti, ett_msg);
 262
 263             /* Append AttributeType description to the end of the "Message" heading */
 264             proto_item_append_text(msg_tree, ": %s (%d)",
 265                                    val_to_str_const(attribute_type, attribute_type_vals, "<Unknown>"),
 266                                    attribute_type);
 267
 268             dissect_mvrp_common1(msg_tree, tvb, msg_offset);
 269
 270             /* MVRP AttributeList is a group of fields
 271              *
 272              * Contains AttributeListLength bytes of data NOT
 273              */
 274             attr_list_ti = proto_tree_add_item(msg_tree, hf_mvrp_attribute_list, tvb,
 275                                                MVRP_ATTRIBUTE_LIST_GROUP_OFFSET + msg_offset,
 276                                                -1, ENC_NA);
 277             attr_list_tree = proto_item_add_subtree(attr_list_ti, ett_attr_list);
 278
 279
 280             /* MVRP supports multiple MRP Vector Attributes per Attribute List.  Handle those
 281              * Vector Attributes in the following while() loop. You will know you are at the
 282              * end of the list of Vector Attributes when the EndMark (0x0000) is encountered
 283              * instead of a Vector Header (guaranteed to not be 0x0000).
 284              */
 285             vect_offset = 0;
 286             while (tvb_get_ntohs(tvb, MVRP_VECTOR_HEADER_OFFSET + msg_offset + vect_offset) != MVRP_END_MARK) {
 287                 /* MVRP VectorAttribute is a group of fields
 288                  *
 289                  * Contains VectorHeader (2 bytes)
 290                  *        + FirstValue (AttributeLength bytes)
 291                  *        + VectorThreePacked (NumberOfValues @ 3/vector bytes)
 292                  *        + VectorFourPacked (NumberOfValues @ 4/vector bytes only for Listener attributes)
 293                  *        bytes of data
 294                  */
 295                 number_of_values = tvb_get_ntohs(tvb, MVRP_NUMBER_OF_VALUES_OFFSET + msg_offset + vect_offset)
 296                                    & MVRP_NUMBER_OF_VALUES_MASK;
 297
 298                 vect_attr_len = 2 + attribute_length + (number_of_values + 2)/3; /* stores 3 values per byte */
 299
 300                 vect_attr_ti = proto_tree_add_item(attr_list_tree, hf_mvrp_vector_attribute, tvb,
 301                                                    MVRP_VECTOR_ATTRIBUTE_GROUP_OFFSET + msg_offset + vect_offset,
 302                                                    vect_attr_len, ENC_NA);
 303
 304                 vect_attr_tree = proto_item_add_subtree(vect_attr_ti, ett_vect_attr);
 305
 306                 dissect_mvrp_common2(vect_attr_tree, tvb, msg_offset + vect_offset);
 307
 308                 if (attribute_type == MVRP_ATTRIBUTE_TYPE_VID) {
 309                     /* MVRP VLAN ID FirstValue is a group of fields
 310                      *
 311                      * Contains VID (2 bytes)
 312                      *        bytes of data
 313                      */
 314                     first_value_ti = proto_tree_add_item(vect_attr_tree, hf_mvrp_first_value, tvb,
 315                                                          MVRP_FIRST_VALUE_GROUP_OFFSET + msg_offset + vect_offset,
 316                                                          attribute_length, ENC_NA);
 317                     first_value_tree = proto_item_add_subtree(first_value_ti, ett_first_value);
 318
 319                     /* Add VLAN components to First Value tree */
 320                     proto_tree_add_item(first_value_tree, hf_mvrp_vid, tvb,
 321                                         MVRP_FIRST_VALUE_GROUP_OFFSET + msg_offset + vect_offset, 2, ENC_BIG_ENDIAN);
 322
 323                     /* Decode three packed events. */
 324                     offset = dissect_mvrp_three_packed_event(vect_attr_tree, tvb,
 325                                                              MVRP_VID_THREE_PACKED_OFFSET + msg_offset + vect_offset,
 326                                                              number_of_values);
 327
 328                 }
 329
 330                 vect_offset += vect_attr_len; /* Move to next Vector Attribute, if there is one */
 331             } /* Multiple VectorAttribute while() */
 332
 333             proto_tree_add_item(attr_list_tree, hf_mvrp_end_mark, tvb, offset, 2, ENC_NA); /* VectorAttribute EndMark */
 334
 335             proto_item_set_len(attr_list_ti, vect_offset); /*without an endmark*/
 336             msg_offset += vect_offset + 2; /*  + endmark; Move to next Message, if there is one */
 337             proto_item_set_len(msg_ti, vect_offset + 2); /*length of message*/
 338
 339         } /* Multiple Message while() */
 340
 341         proto_tree_add_item(mvrp_tree, hf_mvrp_end_mark, tvb, offset+2, 2, ENC_NA); /* Message EndMark */
 342     }
 343 }
 344
 345
 346 /* Register the protocol with Wireshark */
 347 void
 348 proto_register_mrp_mvrp(void)
 349 {
 350     static hf_register_info hf[] = {
 351         { &hf_mvrp_proto_id,
 352             { "Protocol Version",      "mrp-mvrp.protocol_version",
 353               FT_UINT8,  BASE_DEC, NULL, 0x0, NULL, HFILL }
 354         },
 355         { &hf_mvrp_message, /* Message is a group of fields */
 356             { "Message",               "mrp-mvrp.message",
 357               FT_NONE,  BASE_NONE, NULL, 0x0, NULL, HFILL }
 358         },
 359         { &hf_mvrp_attribute_type,
 360             { "Attribute Type",        "mrp-mvrp.attribute_type",
 361               FT_UINT8,  BASE_DEC, VALS(attribute_type_vals), 0x0, NULL, HFILL }
 362         },
 363         { &hf_mvrp_attribute_length,
 364             { "Attribute Length",      "mrp-mvrp.attribute_length",
 365               FT_UINT8,  BASE_DEC, NULL, 0x0, NULL, HFILL }
 366         },
 367         { &hf_mvrp_attribute_list, /* AttributeList is a group of fields */
 368             { "Attribute List",        "mrp-mvrp.attribute_list",
 369               FT_NONE,  BASE_NONE, NULL, 0x0, NULL, HFILL }
 370         },
 371         { &hf_mvrp_vector_attribute, /* VectorAttribute is a group of fields */
 372             { "Vector Attribute",      "mrp-mvrp.vector_attribute",
 373               FT_NONE,  BASE_NONE, NULL, 0x0, NULL, HFILL }
 374         },
 375         { &hf_mvrp_vector_header,
 376             { "Vector Header",         "mrp-mvrp.vector_header",
 377               FT_UINT16, BASE_HEX, NULL, 0x0, NULL, HFILL }
 378         },
 379         { &hf_mvrp_leave_all_event,
 380             { "Leave All Event",       "mrp-mvrp.leave_all_event",
 381               FT_UINT16, BASE_DEC, VALS(leave_all_vals), MVRP_LEAVE_ALL_EVENT_MASK, NULL, HFILL }
 382         },
 383         { &hf_mvrp_number_of_values,
 384             { "Number of Values",      "mrp-mvrp.number_of_values",
 385               FT_UINT16, BASE_DEC, NULL, MVRP_NUMBER_OF_VALUES_MASK, NULL, HFILL }
 386         },
 387         { &hf_mvrp_first_value, /* FirstValue is a group of fields */
 388             { "First Value",           "mrp-mvrp.first_value",
 389               FT_NONE,  BASE_NONE, NULL, 0x0, NULL, HFILL }
 390         },
 391         { &hf_mvrp_vid,
 392             { "VLAN ID",               "mrp-mvrp.vid",
 393               FT_UINT16, BASE_DEC,  NULL, 0x0, NULL, HFILL }
 394         },
 395         { &hf_mvrp_three_packed_event,
 396             { "Attribute Event",       "mrp-msrp.three_packed_event",
 397               FT_UINT8, BASE_DEC,  VALS(three_packed_vals), 0x0, NULL, HFILL }
 398         },
 399         { &hf_mvrp_end_mark,
 400             { "End Mark",              "mrp-mvrp.end_mark",
 401               FT_UINT16, BASE_HEX, NULL, 0x0, NULL, HFILL }
 402         },
 403     };
 404
 405     /* Setup protocol subtree array */
 406     static gint *ett[] = {
 407         &ett_mvrp,
 408         &ett_msg,
 409         &ett_attr_list,
 410         &ett_vect_attr,
 411         &ett_vector_header,
 412         &ett_first_value
 413     };
 414
 415     /* Register the protocol name and description */
 416     proto_mvrp = proto_register_protocol("Multiple VLAN Registration Protocol",
 417                                          "MRP-MVRP", "mrp-mvrp");
 418
 419     /* Required function calls to register the header fields and subtrees used */
 420     proto_register_field_array(proto_mvrp, hf, array_length(hf));
 421     proto_register_subtree_array(ett, array_length(ett));
 422 }
 423
 424 void
 425 proto_reg_handoff_mrp_mvrp(void)
 426 {
 427     dissector_handle_t mvrp_handle;
 428
 429     mvrp_handle = create_dissector_handle(dissect_mvrp, proto_mvrp);
 430     dissector_add_uint("ethertype", ETHERTYPE_MVRP, mvrp_handle);
 431 }
 432 /*
 433 * Editor modelines - http://www.wireshark.org/tools/modelines.html
 434 *
 435 * Local variables:
 436 * c-basic-offset: 4
 437 * tab-width: 8
 438 * indent-tabs-mode: nil
 439 * End:
 440 *
 441 * ex: set shiftwidth=4 tabstop=8 expandtab:
 442 * :indentSize=4:tabSize=8:noTabs=true:
 443 */