epan/dissectors/packet-dvb-nit.c

   1 /* packet-dvb-nit.c
   2  * Routines for DVB (ETSI EN 300 468) Network Information Table (NIT) dissection
   3  * Copyright 2012, Guy Martin <gmsoft@tuxicoman.be>
   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 #include "config.h"
  13
  14 #include <epan/packet.h>
  15 #include <epan/tfs.h>
  16 #include "packet-mpeg-sect.h"
  17 #include "packet-mpeg-descriptor.h"
  18
  19 void proto_register_dvb_nit(void);
  20 void proto_reg_handoff_dvb_nit(void);
  21
  22 static int proto_dvb_nit;
  23 static int hf_dvb_nit_network_id;
  24 static int hf_dvb_nit_reserved1;
  25 static int hf_dvb_nit_version_number;
  26 static int hf_dvb_nit_current_next_indicator;
  27 static int hf_dvb_nit_section_number;
  28 static int hf_dvb_nit_last_section_number;
  29 static int hf_dvb_nit_reserved2;
  30
  31 static int hf_dvb_nit_network_descriptors_length;
  32 static int hf_dvb_nit_reserved3;
  33 static int hf_dvb_nit_transport_stream_loop_length;
  34
  35 static int hf_dvb_nit_transport_stream_id;
  36 static int hf_dvb_nit_original_network_id;
  37 static int hf_dvb_nit_reserved4;
  38 static int hf_dvb_nit_transport_descriptors_length;
  39
  40 static int ett_dvb_nit;
  41 static int ett_dvb_nit_ts;
  42
  43 static dissector_handle_t dvb_nit_handle;
  44
  45 #define DVB_NIT_RESERVED1_MASK                            0xC0
  46 #define DVB_NIT_VERSION_NUMBER_MASK                       0x3E
  47 #define DVB_NIT_CURRENT_NEXT_INDICATOR_MASK               0x01
  48 #define DVB_NIT_RESERVED2_MASK                          0xF000
  49 #define DVB_NIT_NETWORK_DESCRIPTORS_LENGTH_MASK         0x0FFF
  50 #define DVB_NIT_RESERVED3_MASK                          0xF000
  51 #define DVB_NIT_TRANSPORT_STREAM_LOOP_LENGTH_MASK       0x0FFF
  52 #define DVB_NIT_RESERVED4_MASK                          0xF000
  53 #define DVB_NIT_TRANSPORT_DESCRIPTORS_LENGTH_MASK       0x0FFF
  54
  55 static int
  56 dissect_dvb_nit(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
  57 {
  58
  59     unsigned    offset = 0;
  60     unsigned    ts_desc_len, desc_loop_len, ts_end;
  61
  62     uint16_t    tsid;
  63
  64     proto_item *ti;
  65     proto_tree *dvb_nit_tree;
  66     proto_tree *dvb_nit_ts_tree;
  67
  68     col_set_str(pinfo->cinfo, COL_INFO, "Network Information Table (NIT)");
  69
  70     ti = proto_tree_add_item(tree, proto_dvb_nit, tvb, offset, -1, ENC_NA);
  71     dvb_nit_tree = proto_item_add_subtree(ti, ett_dvb_nit);
  72
  73     offset += packet_mpeg_sect_header(tvb, offset, dvb_nit_tree, NULL, NULL);
  74
  75     proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_network_id,                 tvb, offset, 2, ENC_BIG_ENDIAN);
  76     offset += 2;
  77
  78     proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_reserved1,                  tvb, offset, 1, ENC_BIG_ENDIAN);
  79     proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_version_number,             tvb, offset, 1, ENC_BIG_ENDIAN);
  80     proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_current_next_indicator,     tvb, offset, 1, ENC_BIG_ENDIAN);
  81     offset += 1;
  82
  83     proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_section_number,             tvb, offset, 1, ENC_BIG_ENDIAN);
  84     offset += 1;
  85
  86     proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_last_section_number,        tvb, offset, 1, ENC_BIG_ENDIAN);
  87     offset += 1;
  88
  89     proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_reserved2,                  tvb, offset, 2, ENC_BIG_ENDIAN);
  90     proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_network_descriptors_length, tvb, offset, 2, ENC_BIG_ENDIAN);
  91     desc_loop_len = tvb_get_ntohs(tvb, offset) & DVB_NIT_NETWORK_DESCRIPTORS_LENGTH_MASK;
  92     offset += 2;
  93
  94     offset += proto_mpeg_descriptor_loop_dissect(tvb, offset, desc_loop_len, dvb_nit_tree);
  95
  96     proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_reserved3,                    tvb, offset, 2, ENC_BIG_ENDIAN);
  97     proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_transport_stream_loop_length, tvb, offset, 2, ENC_BIG_ENDIAN);
  98     ts_end = offset + (tvb_get_ntohs(tvb, offset) & DVB_NIT_TRANSPORT_STREAM_LOOP_LENGTH_MASK);
  99     offset += 2;
 100
 101     while (offset < ts_end) {
 102         tsid = tvb_get_ntohs(tvb, offset);
 103         ts_desc_len = 3 + (tvb_get_ntohs(tvb, offset + 4) & DVB_NIT_TRANSPORT_DESCRIPTORS_LENGTH_MASK);
 104
 105         dvb_nit_ts_tree = proto_tree_add_subtree_format(dvb_nit_tree, tvb, offset, ts_desc_len,
 106                                ett_dvb_nit_ts, NULL, "Stream ID=0x%04hx", tsid);
 107
 108         proto_tree_add_item(dvb_nit_ts_tree, hf_dvb_nit_transport_stream_id, tvb, offset, 2, ENC_BIG_ENDIAN);
 109         offset += 2;
 110
 111         proto_tree_add_item(dvb_nit_ts_tree, hf_dvb_nit_original_network_id, tvb, offset, 2, ENC_BIG_ENDIAN);
 112         offset += 2;
 113
 114         proto_tree_add_item(dvb_nit_ts_tree, hf_dvb_nit_reserved4,                    tvb, offset, 2, ENC_BIG_ENDIAN);
 115         proto_tree_add_item(dvb_nit_ts_tree, hf_dvb_nit_transport_descriptors_length, tvb, offset, 2, ENC_BIG_ENDIAN);
 116         desc_loop_len = tvb_get_ntohs(tvb, offset) & DVB_NIT_TRANSPORT_DESCRIPTORS_LENGTH_MASK;
 117         offset += 2;
 118
 119         offset += proto_mpeg_descriptor_loop_dissect(tvb, offset, desc_loop_len, dvb_nit_ts_tree);
 120     }
 121
 122     offset += packet_mpeg_sect_crc(tvb, pinfo, dvb_nit_tree, 0, offset);
 123
 124     proto_item_set_len(ti, offset);
 125     return offset;
 126 }
 127
 128
 129 void
 130 proto_register_dvb_nit(void)
 131 {
 132
 133     static hf_register_info hf[] = {
 134
 135         { &hf_dvb_nit_network_id, {
 136             "Network ID", "dvb_nit.sid",
 137             FT_UINT16, BASE_HEX, NULL, 0, NULL, HFILL
 138         } },
 139
 140         { &hf_dvb_nit_reserved1, {
 141             "Reserved", "dvb_nit.reserved1",
 142             FT_UINT8, BASE_HEX, NULL, DVB_NIT_RESERVED1_MASK, NULL, HFILL
 143         } },
 144
 145         { &hf_dvb_nit_version_number, {
 146             "Version Number", "dvb_nit.version",
 147             FT_UINT8, BASE_HEX, NULL, DVB_NIT_VERSION_NUMBER_MASK, NULL, HFILL
 148         } },
 149
 150         { &hf_dvb_nit_current_next_indicator, {
 151             "Current/Next Indicator", "dvb_nit.cur_next_ind",
 152             FT_BOOLEAN, 8, TFS(&tfs_current_not_yet), DVB_NIT_CURRENT_NEXT_INDICATOR_MASK, NULL, HFILL
 153         } },
 154
 155         { &hf_dvb_nit_section_number, {
 156             "Section Number", "dvb_nit.sect_num",
 157             FT_UINT8, BASE_DEC, NULL, 0, NULL, HFILL
 158         } },
 159
 160         { &hf_dvb_nit_last_section_number, {
 161             "Last Section Number", "dvb_nit.last_sect_num",
 162             FT_UINT8, BASE_DEC, NULL, 0, NULL, HFILL
 163         } },
 164
 165         { &hf_dvb_nit_reserved2, {
 166             "Reserved", "dvb_nit.reserved2",
 167             FT_UINT16, BASE_HEX, NULL, DVB_NIT_RESERVED2_MASK, NULL, HFILL
 168         } },
 169
 170         { &hf_dvb_nit_network_descriptors_length, {
 171             "Network Descriptors Length", "dvb_nit.network_desc_len",
 172             FT_UINT16, BASE_DEC, NULL, DVB_NIT_NETWORK_DESCRIPTORS_LENGTH_MASK, NULL, HFILL
 173         } },
 174
 175         { &hf_dvb_nit_reserved3, {
 176             "Reserved", "dvb_nit.reserved3",
 177             FT_UINT16, BASE_HEX, NULL, DVB_NIT_RESERVED3_MASK, NULL, HFILL
 178         } },
 179
 180         { &hf_dvb_nit_transport_stream_loop_length, {
 181             "Transport Stream Loop Length", "dvb_nit.ts_loop_len",
 182             FT_UINT16, BASE_DEC, NULL, DVB_NIT_TRANSPORT_STREAM_LOOP_LENGTH_MASK, NULL, HFILL
 183         } },
 184
 185         { &hf_dvb_nit_transport_stream_id, {
 186             "Transport Stream ID", "dvb_nit.ts.id",
 187             FT_UINT16, BASE_HEX, NULL, 0, NULL, HFILL
 188         } },
 189
 190         { &hf_dvb_nit_original_network_id, {
 191             "Original Network ID", "dvb_nit.ts.original_network_id",
 192             FT_UINT16, BASE_HEX, NULL, 0, NULL, HFILL
 193         } },
 194
 195         { &hf_dvb_nit_reserved4, {
 196             "Reserved", "dvb_nit.ts.reserved",
 197             FT_UINT16, BASE_HEX, NULL, DVB_NIT_RESERVED4_MASK, NULL, HFILL
 198         } },
 199
 200         { &hf_dvb_nit_transport_descriptors_length, {
 201             "Transport Descriptors Length", "dvb_nit.ts.desc_len",
 202             FT_UINT16, BASE_DEC, NULL, DVB_NIT_TRANSPORT_DESCRIPTORS_LENGTH_MASK, NULL, HFILL
 203         } },
 204
 205     };
 206
 207     static int *ett[] = {
 208         &ett_dvb_nit,
 209         &ett_dvb_nit_ts
 210     };
 211
 212     proto_dvb_nit = proto_register_protocol("DVB Network Information Table", "DVB NIT", "dvb_nit");
 213
 214     proto_register_field_array(proto_dvb_nit, hf, array_length(hf));
 215     proto_register_subtree_array(ett, array_length(ett));
 216
 217     dvb_nit_handle = register_dissector("dvb_nit", dissect_dvb_nit, proto_dvb_nit);
 218 }
 219
 220
 221 void proto_reg_handoff_dvb_nit(void)
 222 {
 223     dissector_add_uint("mpeg_sect.tid", DVB_NIT_TID, dvb_nit_handle);
 224     dissector_add_uint("mpeg_sect.tid", DVB_NIT_TID_OTHER, dvb_nit_handle);
 225 }
 226
 227
 228 /*
 229  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 230  *
 231  * Local variables:
 232  * c-basic-offset: 4
 233  * tab-width: 8
 234  * indent-tabs-mode: nil
 235  * End:
 236  *
 237  * vi: set shiftwidth=4 tabstop=8 expandtab:
 238  * :indentSize=4:tabSize=8:noTabs=true:
 239  */