epan/dissectors/packet-maap.c

   1 /* packet-maap.c
   2  * Routines for 802.3 MAC Address Allocation Protocol defined by IEEE1722
   3  * Copyright 2012, Jason Damori, Biamp Systems <jdamori at biamp dot com>
   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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  24  *
  25  */
  26
  27
  28 #include "config.h"
  29
  30 #include <epan/packet.h>
  31 #include <epan/to_str.h>
  32 #include <epan/etypes.h>
  33
  34 /* MAAP starts after common 1722 header */
  35 #define MAAP_START_OFFSET                   1
  36
  37 /* MAAP Field Offsets */
  38 #define MAAP_MSG_TYPE_OFFSET                0+MAAP_START_OFFSET
  39 #define MAAP_VERSION_OFFSET                 1+MAAP_START_OFFSET
  40 #define MAAP_STREAM_ID_OFFSET               3+MAAP_START_OFFSET
  41 #define MAAP_REQ_START_ADDR_OFFSET          11+MAAP_START_OFFSET
  42 #define MAAP_REQ_COUNT_OFFSET               17+MAAP_START_OFFSET
  43 #define MAAP_CONFLICT_START_ADDR_OFFSET     19+MAAP_START_OFFSET
  44 #define MAAP_CONFLICT_COUNT_OFFSET          25+MAAP_START_OFFSET
  45
  46 /* Bit Field Masks */
  47 #define MAAP_MSG_TYPE_MASK                  0x0f
  48 #define MAAP_VERSION_MASK                   0xf8
  49 #define MAAP_DATA_LEN_MASK                  0x07ff
  50
  51 /* MAAP message_type */
  52 #define MAAP_MSG_TYPE_RESERVED_0            0x00
  53 #define MAAP_MSG_TYPE_PROBE                 0x01
  54 #define MAAP_MSG_TYPE_DEFEND                0x02
  55 #define MAAP_MSG_TYPE_ANNOUNCE              0x03
  56 #define MAAP_MSG_TYPE_RESERVED_4            0x04
  57 #define MAAP_MSG_TYPE_RESERVED_5            0x05
  58
  59 static const value_string maap_msg_type_vals [] = {
  60     {MAAP_MSG_TYPE_PROBE,       "MAAP_PROBE"},
  61     {MAAP_MSG_TYPE_DEFEND,      "MAAP_DEFEND"},
  62     {MAAP_MSG_TYPE_ANNOUNCE,    "MAAP_ANNOUNCE"},
  63     {0,                         NULL}
  64 };
  65
  66 /**********************************************************/
  67 /* Initialize the protocol and registered fields          */
  68 /**********************************************************/
  69 static int proto_maap = -1;
  70
  71 /* MAAP PDU */
  72 static int hf_maap_message_type = -1;
  73 static int hf_maap_version = -1;
  74 static int hf_maap_data_length = -1;
  75 static int hf_maap_stream_id = -1;
  76 static int hf_maap_req_start_addr = -1;
  77 static int hf_maap_req_count = -1;
  78 static int hf_maap_conflict_start_addr = -1;
  79 static int hf_maap_conflict_count = -1;
  80
  81 /* Initialize the subtree pointers */
  82 static int ett_maap = -1;
  83
  84 static void
  85 dissect_maap(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
  86 {
  87     guint8      maap_msg_type;
  88     proto_item *maap_item     = NULL;
  89     proto_tree *maap_tree     = NULL;
  90
  91     col_set_str(pinfo->cinfo, COL_PROTOCOL, "MAAP");
  92     col_clear(pinfo->cinfo, COL_INFO);
  93
  94     /* The maap msg type will be handy in a moment */
  95     maap_msg_type = tvb_get_guint8(tvb, MAAP_MSG_TYPE_OFFSET);
  96     maap_msg_type &= 0x0f;
  97
  98     /* Display the name of the packet type in the info column. */
  99     col_add_fstr(pinfo->cinfo, COL_INFO, "%s:",
 100                 val_to_str(maap_msg_type, maap_msg_type_vals,
 101                             "Unknown Type(0x%02x)"));
 102
 103     /* Now, we'll add the start and conflict addresses and counts to the info column as appropriate */
 104     switch (maap_msg_type)
 105     {
 106     case MAAP_MSG_TYPE_PROBE:
 107     case MAAP_MSG_TYPE_ANNOUNCE:
 108         col_append_fstr(pinfo->cinfo, COL_INFO, " req_start=%s, cnt=%d",
 109                         tvb_ether_to_str(tvb, MAAP_REQ_START_ADDR_OFFSET),
 110                         tvb_get_ntohs(tvb, MAAP_REQ_COUNT_OFFSET));
 111
 112         break;
 113     case MAAP_MSG_TYPE_DEFEND:
 114         col_append_fstr(pinfo->cinfo, COL_INFO, " conflict_start=%s, cnt=%d",
 115                         tvb_ether_to_str(tvb, MAAP_CONFLICT_START_ADDR_OFFSET),
 116                         tvb_get_ntohs(tvb, MAAP_CONFLICT_COUNT_OFFSET));
 117         break;
 118     default:
 119         /* no info for reserved or unknown msg types */
 120         break;
 121     }
 122
 123
 124     if (tree) {
 125         maap_item = proto_tree_add_item(tree, proto_maap, tvb, MAAP_START_OFFSET, -1, ENC_NA);
 126         maap_tree = proto_item_add_subtree(maap_item, ett_maap);
 127
 128         proto_tree_add_item(maap_tree, hf_maap_message_type,        tvb, MAAP_MSG_TYPE_OFFSET,            1, ENC_BIG_ENDIAN);
 129         proto_tree_add_item(maap_tree, hf_maap_version,             tvb, MAAP_VERSION_OFFSET,             1, ENC_BIG_ENDIAN);
 130         proto_tree_add_item(maap_tree, hf_maap_data_length,         tvb, MAAP_VERSION_OFFSET,             2, ENC_BIG_ENDIAN);
 131         proto_tree_add_item(maap_tree, hf_maap_stream_id,           tvb, MAAP_STREAM_ID_OFFSET,           8, ENC_BIG_ENDIAN);
 132         proto_tree_add_item(maap_tree, hf_maap_req_start_addr,      tvb, MAAP_REQ_START_ADDR_OFFSET,      6, ENC_NA);
 133         proto_tree_add_item(maap_tree, hf_maap_req_count,           tvb, MAAP_REQ_COUNT_OFFSET,           2, ENC_BIG_ENDIAN);
 134         proto_tree_add_item(maap_tree, hf_maap_conflict_start_addr, tvb, MAAP_CONFLICT_START_ADDR_OFFSET, 6, ENC_NA);
 135         proto_tree_add_item(maap_tree, hf_maap_conflict_count,      tvb, MAAP_CONFLICT_COUNT_OFFSET,      2, ENC_BIG_ENDIAN);
 136     }
 137 } /* end dissect_maap() */
 138
 139 /* Register the protocol with Wireshark */
 140 void
 141 proto_register_maap(void)
 142 {
 143     static hf_register_info hf[] = {
 144         { &hf_maap_message_type,
 145             { "Message Type", "maap.message_type",
 146                 FT_UINT8, BASE_HEX,
 147                 VALS(maap_msg_type_vals), MAAP_MSG_TYPE_MASK,
 148                 NULL, HFILL }},
 149
 150         { &hf_maap_version,
 151             { "MAAP Version", "maap.version",
 152                 FT_UINT8, BASE_HEX,
 153                 NULL, MAAP_VERSION_MASK,
 154                 NULL, HFILL }},
 155
 156         { &hf_maap_data_length,
 157             { "Data Length", "maap.data_length",
 158                 FT_UINT16, BASE_HEX,
 159                 NULL, MAAP_DATA_LEN_MASK,
 160                 NULL, HFILL }},
 161
 162         { &hf_maap_stream_id,
 163             { "Stream ID", "maap.stream_id",
 164                 FT_UINT64, BASE_HEX,
 165                 NULL, 0x00,
 166                 NULL, HFILL }},
 167
 168         { &hf_maap_req_start_addr,
 169             { "Requested Start Address", "maap.req_start_addr",
 170                 FT_ETHER, BASE_NONE,
 171                 NULL, 0x00,
 172                 NULL, HFILL }},
 173
 174         { &hf_maap_req_count,
 175             { "Request Count", "maap.req_count",
 176                 FT_UINT16, BASE_HEX,
 177                 NULL, 0x00,
 178                 NULL, HFILL }},
 179
 180         { &hf_maap_conflict_start_addr,
 181             { "Conflict Start Address", "maap.conflict_start_addr",
 182                 FT_ETHER, BASE_NONE,
 183                 NULL, 0x00,
 184                 NULL, HFILL }},
 185
 186         { &hf_maap_conflict_count,
 187             { "Conflict Count", "maap.conflict_count",
 188                 FT_UINT16, BASE_HEX,
 189                 NULL, 0x00,
 190                 NULL, HFILL }}
 191     }; /* end of static hf_register_info hf[] = */
 192
 193     /* Setup protocol subtree array */
 194     static gint *ett[] = { &ett_maap };
 195
 196     /* Register the protocol name and description */
 197     proto_maap = proto_register_protocol (
 198         "IEEE 1722 MAAP Protocol", /* name */
 199         "MAAP", /* short name */
 200         "maap" /* abbrev */
 201         );
 202
 203     /* Required function calls to register the header fields and subtrees used */
 204     proto_register_field_array(proto_maap, hf, array_length(hf));
 205     proto_register_subtree_array(ett, array_length(ett));
 206
 207 } /* end proto_register_maap() */
 208
 209 void
 210 proto_reg_handoff_maap(void)
 211 {
 212     dissector_handle_t maap_handle;
 213
 214     maap_handle = create_dissector_handle(dissect_maap, proto_maap);
 215     dissector_add_uint("ieee1722.subtype", 0x7E, maap_handle);
 216 }