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  * Wireshark - Network traffic analyzer
   6  * By Gerald Combs <gerald@wireshark.org>
   7  * Copyright 1998 Gerald Combs
   8  *
   9  * SPDX-License-Identifier: GPL-2.0-or-later
  10  *
  11  */
  12
  13
  14 #include "config.h"
  15
  16 #include <epan/packet.h>
  17 #include <epan/to_str.h>
  18
  19 void proto_register_maap(void);
  20 void proto_reg_handoff_maap(void);
  21
  22 static dissector_handle_t maap_handle;
  23
  24 /* MAAP starts after common 1722 header */
  25 #define MAAP_START_OFFSET                   1
  26
  27 /* MAAP Field Offsets */
  28 #define MAAP_MSG_TYPE_OFFSET                0+MAAP_START_OFFSET
  29 #define MAAP_VERSION_OFFSET                 1+MAAP_START_OFFSET
  30 #define MAAP_STREAM_ID_OFFSET               3+MAAP_START_OFFSET
  31 #define MAAP_REQ_START_ADDR_OFFSET          11+MAAP_START_OFFSET
  32 #define MAAP_REQ_COUNT_OFFSET               17+MAAP_START_OFFSET
  33 #define MAAP_CONFLICT_START_ADDR_OFFSET     19+MAAP_START_OFFSET
  34 #define MAAP_CONFLICT_COUNT_OFFSET          25+MAAP_START_OFFSET
  35
  36 /* Bit Field Masks */
  37 #define MAAP_MSG_TYPE_MASK                  0x0f
  38 #define MAAP_VERSION_MASK                   0xf8
  39 #define MAAP_DATA_LEN_MASK                  0x07ff
  40
  41 /* MAAP message_type */
  42 #define MAAP_MSG_TYPE_RESERVED_0            0x00
  43 #define MAAP_MSG_TYPE_PROBE                 0x01
  44 #define MAAP_MSG_TYPE_DEFEND                0x02
  45 #define MAAP_MSG_TYPE_ANNOUNCE              0x03
  46 #define MAAP_MSG_TYPE_RESERVED_4            0x04
  47 #define MAAP_MSG_TYPE_RESERVED_5            0x05
  48
  49 static const value_string maap_msg_type_vals [] = {
  50     {MAAP_MSG_TYPE_PROBE,       "MAAP_PROBE"},
  51     {MAAP_MSG_TYPE_DEFEND,      "MAAP_DEFEND"},
  52     {MAAP_MSG_TYPE_ANNOUNCE,    "MAAP_ANNOUNCE"},
  53     {0,                         NULL}
  54 };
  55
  56 /**********************************************************/
  57 /* Initialize the protocol and registered fields          */
  58 /**********************************************************/
  59 static int proto_maap;
  60
  61 /* MAAP PDU */
  62 static int hf_maap_message_type;
  63 static int hf_maap_version;
  64 static int hf_maap_data_length;
  65 static int hf_maap_stream_id;
  66 static int hf_maap_req_start_addr;
  67 static int hf_maap_req_count;
  68 static int hf_maap_conflict_start_addr;
  69 static int hf_maap_conflict_count;
  70
  71 /* Initialize the subtree pointers */
  72 static int ett_maap;
  73
  74 static int
  75 dissect_maap(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
  76 {
  77     uint8_t     maap_msg_type;
  78     proto_item *maap_item     = NULL;
  79     proto_tree *maap_tree     = NULL;
  80
  81     col_set_str(pinfo->cinfo, COL_PROTOCOL, "MAAP");
  82     col_clear(pinfo->cinfo, COL_INFO);
  83
  84     /* The maap msg type will be handy in a moment */
  85     maap_msg_type = tvb_get_uint8(tvb, MAAP_MSG_TYPE_OFFSET);
  86     maap_msg_type &= 0x0f;
  87
  88     /* Display the name of the packet type in the info column. */
  89     col_add_fstr(pinfo->cinfo, COL_INFO, "%s:",
  90                 val_to_str(maap_msg_type, maap_msg_type_vals,
  91                             "Unknown Type(0x%02x)"));
  92
  93     /* Now, we'll add the start and conflict addresses and counts to the info column as appropriate */
  94     switch (maap_msg_type)
  95     {
  96     case MAAP_MSG_TYPE_PROBE:
  97     case MAAP_MSG_TYPE_ANNOUNCE:
  98         col_append_fstr(pinfo->cinfo, COL_INFO, " req_start=%s, cnt=%d",
  99                         tvb_ether_to_str(pinfo->pool, tvb, MAAP_REQ_START_ADDR_OFFSET),
 100                         tvb_get_ntohs(tvb, MAAP_REQ_COUNT_OFFSET));
 101
 102         break;
 103     case MAAP_MSG_TYPE_DEFEND:
 104         col_append_fstr(pinfo->cinfo, COL_INFO, " conflict_start=%s, cnt=%d",
 105                         tvb_ether_to_str(pinfo->pool, tvb, MAAP_CONFLICT_START_ADDR_OFFSET),
 106                         tvb_get_ntohs(tvb, MAAP_CONFLICT_COUNT_OFFSET));
 107         break;
 108     default:
 109         /* no info for reserved or unknown msg types */
 110         break;
 111     }
 112
 113
 114     if (tree) {
 115         maap_item = proto_tree_add_item(tree, proto_maap, tvb, MAAP_START_OFFSET, -1, ENC_NA);
 116         maap_tree = proto_item_add_subtree(maap_item, ett_maap);
 117
 118         proto_tree_add_item(maap_tree, hf_maap_message_type,        tvb, MAAP_MSG_TYPE_OFFSET,            1, ENC_BIG_ENDIAN);
 119         proto_tree_add_item(maap_tree, hf_maap_version,             tvb, MAAP_VERSION_OFFSET,             1, ENC_BIG_ENDIAN);
 120         proto_tree_add_item(maap_tree, hf_maap_data_length,         tvb, MAAP_VERSION_OFFSET,             2, ENC_BIG_ENDIAN);
 121         proto_tree_add_item(maap_tree, hf_maap_stream_id,           tvb, MAAP_STREAM_ID_OFFSET,           8, ENC_BIG_ENDIAN);
 122         proto_tree_add_item(maap_tree, hf_maap_req_start_addr,      tvb, MAAP_REQ_START_ADDR_OFFSET,      6, ENC_NA);
 123         proto_tree_add_item(maap_tree, hf_maap_req_count,           tvb, MAAP_REQ_COUNT_OFFSET,           2, ENC_BIG_ENDIAN);
 124         proto_tree_add_item(maap_tree, hf_maap_conflict_start_addr, tvb, MAAP_CONFLICT_START_ADDR_OFFSET, 6, ENC_NA);
 125         proto_tree_add_item(maap_tree, hf_maap_conflict_count,      tvb, MAAP_CONFLICT_COUNT_OFFSET,      2, ENC_BIG_ENDIAN);
 126     }
 127
 128     return tvb_captured_length(tvb);
 129 } /* end dissect_maap() */
 130
 131 /* Register the protocol with Wireshark */
 132 void
 133 proto_register_maap(void)
 134 {
 135     static hf_register_info hf[] = {
 136         { &hf_maap_message_type,
 137             { "Message Type", "maap.message_type",
 138                 FT_UINT8, BASE_HEX,
 139                 VALS(maap_msg_type_vals), MAAP_MSG_TYPE_MASK,
 140                 NULL, HFILL }},
 141
 142         { &hf_maap_version,
 143             { "MAAP Version", "maap.version",
 144                 FT_UINT8, BASE_HEX,
 145                 NULL, MAAP_VERSION_MASK,
 146                 NULL, HFILL }},
 147
 148         { &hf_maap_data_length,
 149             { "Data Length", "maap.data_length",
 150                 FT_UINT16, BASE_HEX,
 151                 NULL, MAAP_DATA_LEN_MASK,
 152                 NULL, HFILL }},
 153
 154         { &hf_maap_stream_id,
 155             { "Stream ID", "maap.stream_id",
 156                 FT_UINT64, BASE_HEX,
 157                 NULL, 0x00,
 158                 NULL, HFILL }},
 159
 160         { &hf_maap_req_start_addr,
 161             { "Requested Start Address", "maap.req_start_addr",
 162                 FT_ETHER, BASE_NONE,
 163                 NULL, 0x00,
 164                 NULL, HFILL }},
 165
 166         { &hf_maap_req_count,
 167             { "Request Count", "maap.req_count",
 168                 FT_UINT16, BASE_HEX,
 169                 NULL, 0x00,
 170                 NULL, HFILL }},
 171
 172         { &hf_maap_conflict_start_addr,
 173             { "Conflict Start Address", "maap.conflict_start_addr",
 174                 FT_ETHER, BASE_NONE,
 175                 NULL, 0x00,
 176                 NULL, HFILL }},
 177
 178         { &hf_maap_conflict_count,
 179             { "Conflict Count", "maap.conflict_count",
 180                 FT_UINT16, BASE_HEX,
 181                 NULL, 0x00,
 182                 NULL, HFILL }}
 183     }; /* end of static hf_register_info hf[] = */
 184
 185     /* Setup protocol subtree array */
 186     static int *ett[] = { &ett_maap };
 187
 188     /* Register the protocol name and description */
 189     proto_maap = proto_register_protocol (
 190         "IEEE 1722 MAAP Protocol", /* name */
 191         "MAAP", /* short name */
 192         "maap" /* abbrev */
 193         );
 194
 195     /* Required function calls to register the header fields and subtrees used */
 196     proto_register_field_array(proto_maap, hf, array_length(hf));
 197     proto_register_subtree_array(ett, array_length(ett));
 198
 199     /* Register the dissector */
 200     maap_handle = register_dissector("maap", dissect_maap, proto_maap);
 201
 202 } /* end proto_register_maap() */
 203
 204 void
 205 proto_reg_handoff_maap(void)
 206 {
 207     dissector_add_uint("ieee1722.subtype", 0xFE, maap_handle);
 208 }
 209
 210 /*
 211  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 212  *
 213  * Local variables:
 214  * c-basic-offset: 4
 215  * tab-width: 8
 216  * indent-tabs-mode: nil
 217  * End:
 218  *
 219  * vi: set shiftwidth=4 tabstop=8 expandtab:
 220  * :indentSize=4:tabSize=8:noTabs=true:
 221  */