epan/dissectors/packet-dvb-sit.c

   1 /* packet-dvb-sit.c
   2  * Routines for DVB (ETSI EN 300 468) Selection Information Table (SIT) dissection
   3  * Copyright 2021, Roman Volkov <volkoff_roman@ukr.net>
   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_sit(void);
  20 void proto_reg_handoff_dvb_sit(void);
  21
  22 static dissector_handle_t dvb_sit_handle;
  23
  24 static int proto_dvb_sit;
  25
  26 static int hf_dvb_sit_reserved_future_use1;
  27 static int hf_dvb_sit_reserved;
  28 static int hf_dvb_sit_version_number;
  29 static int hf_dvb_sit_current_next_indicator;
  30 static int hf_dvb_sit_section_number;
  31 static int hf_dvb_sit_last_section_number;
  32 static int hf_dvb_sit_reserved_future_use2;
  33 static int hf_dvb_sit_transmission_info_len;
  34 static int hf_dvb_sit_service_id;
  35 static int hf_dvb_sit_reserved_future_use3;
  36 static int hf_dvb_sit_running_status;
  37 static int hf_dvb_sit_service_descriptors_length;
  38
  39 static int ett_dvb_sit;
  40 static int ett_dvb_sit_service;
  41
  42 #define DVB_SIT_RESERVED_MASK                   0xC0
  43 #define DVB_SIT_VERSION_NUMBER_MASK             0x3E
  44 #define DVB_SIT_CURRENT_NEXT_INDICATOR_MASK     0x01
  45
  46 #define DVB_SIT_RESERVED_FUTURE_USE2_MASK       0xF000
  47 #define DVB_SIT_TRANSMISSION_INFO_MASK          0x0FFF
  48
  49 #define DVB_SIT_RESERVED_FUTURE_USE3_MASK       0x8000
  50 #define DVB_SIT_RUNNING_STATUS_MASK             0x7000
  51 #define DVB_SIT_SERVICE_DESCRIPTORS_LENGTH_MASK 0x0FFF
  52
  53 static const value_string dvb_sit_running_status_vals[] = {
  54     { 0, "Undefined" },
  55     { 1, "Not Running" },
  56     { 2, "Starts in a few seconds" },
  57     { 3, "Pausing" },
  58     { 4, "Running" },
  59     { 5, "Service off-air" },
  60
  61     { 0, NULL }
  62 };
  63
  64 static int
  65 dissect_dvb_sit(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
  66 {
  67
  68     unsigned    offset = 0, length = 0;
  69     unsigned    descriptor_len;
  70     uint16_t    svc_id;
  71
  72     proto_item *ti;
  73     proto_tree *dvb_sit_tree;
  74     proto_tree *dvb_sit_service_tree;
  75
  76     /* The TVB should start right after the section_length in the Section packet */
  77
  78     col_set_str(pinfo->cinfo, COL_INFO, "Selection Information Table (SIT)");
  79
  80     ti = proto_tree_add_item(tree, proto_dvb_sit, tvb, offset, -1, ENC_NA);
  81     dvb_sit_tree = proto_item_add_subtree(ti, ett_dvb_sit);
  82
  83     offset += packet_mpeg_sect_header(tvb, offset, dvb_sit_tree, &length, NULL);
  84     length -= 4;
  85
  86     proto_tree_add_item(dvb_sit_tree, hf_dvb_sit_reserved_future_use1,   tvb, offset, 2, ENC_BIG_ENDIAN);
  87     offset += 2;
  88
  89     proto_tree_add_item(dvb_sit_tree, hf_dvb_sit_reserved,               tvb, offset, 1, ENC_BIG_ENDIAN);
  90     proto_tree_add_item(dvb_sit_tree, hf_dvb_sit_version_number,         tvb, offset, 1, ENC_BIG_ENDIAN);
  91     proto_tree_add_item(dvb_sit_tree, hf_dvb_sit_current_next_indicator, tvb, offset, 1, ENC_BIG_ENDIAN);
  92     offset += 1;
  93
  94     proto_tree_add_item(dvb_sit_tree, hf_dvb_sit_section_number,         tvb, offset, 1, ENC_BIG_ENDIAN);
  95     offset += 1;
  96
  97     proto_tree_add_item(dvb_sit_tree, hf_dvb_sit_last_section_number,    tvb, offset, 1, ENC_BIG_ENDIAN);
  98     offset += 1;
  99
 100     descriptor_len = tvb_get_ntohs(tvb, offset) & DVB_SIT_TRANSMISSION_INFO_MASK;
 101     proto_tree_add_item(dvb_sit_tree, hf_dvb_sit_reserved_future_use2,   tvb, offset, 2, ENC_BIG_ENDIAN);
 102     proto_tree_add_item(dvb_sit_tree, hf_dvb_sit_transmission_info_len,  tvb, offset, 2, ENC_BIG_ENDIAN);
 103     offset += 2;
 104
 105     offset += proto_mpeg_descriptor_loop_dissect(tvb, offset, descriptor_len, dvb_sit_tree);
 106
 107     if (offset >= length)
 108         return offset;
 109
 110     /* Parse all the services */
 111     while (offset < length) {
 112
 113         svc_id = tvb_get_ntohs(tvb, offset);
 114         dvb_sit_service_tree = proto_tree_add_subtree_format(dvb_sit_tree, tvb, offset, 5,
 115                     ett_dvb_sit_service, NULL, "Service 0x%04hx", svc_id);
 116
 117         proto_tree_add_item(dvb_sit_service_tree, hf_dvb_sit_service_id,                 tvb, offset, 2, ENC_BIG_ENDIAN);
 118         offset += 2;
 119
 120         proto_tree_add_item(dvb_sit_service_tree, hf_dvb_sit_reserved_future_use3,       tvb, offset, 2, ENC_BIG_ENDIAN);
 121         proto_tree_add_item(dvb_sit_service_tree, hf_dvb_sit_running_status,             tvb, offset, 2, ENC_BIG_ENDIAN);
 122         proto_tree_add_item(dvb_sit_service_tree, hf_dvb_sit_service_descriptors_length, tvb, offset, 2, ENC_BIG_ENDIAN);
 123         descriptor_len = tvb_get_ntohs(tvb, offset) & DVB_SIT_SERVICE_DESCRIPTORS_LENGTH_MASK;
 124         offset += 2;
 125
 126         offset += proto_mpeg_descriptor_loop_dissect(tvb, offset, descriptor_len, dvb_sit_service_tree);
 127     }
 128
 129     offset += packet_mpeg_sect_crc(tvb, pinfo, dvb_sit_tree, 0, offset);
 130     proto_item_set_len(ti, offset);
 131     return tvb_captured_length(tvb);
 132 }
 133
 134
 135 void
 136 proto_register_dvb_sit(void)
 137 {
 138
 139     static hf_register_info hf[] = {
 140
 141         { &hf_dvb_sit_reserved_future_use1, {
 142             "Reserved", "dvb_sit.reserved_future_use1",
 143             FT_UINT16, BASE_HEX, NULL, 0, NULL, HFILL
 144         } },
 145
 146         { &hf_dvb_sit_reserved, {
 147             "Reserved", "dvb_sit.reserved",
 148             FT_UINT8, BASE_HEX, NULL, DVB_SIT_RESERVED_MASK, NULL, HFILL
 149         } },
 150
 151         { &hf_dvb_sit_version_number, {
 152             "Version Number", "dvb_sit.version",
 153             FT_UINT8, BASE_HEX, NULL, DVB_SIT_VERSION_NUMBER_MASK, NULL, HFILL
 154         } },
 155
 156         { &hf_dvb_sit_current_next_indicator, {
 157             "Current/Next Indicator", "dvb_sit.cur_next_ind",
 158             FT_BOOLEAN, 8, TFS(&tfs_current_not_yet), DVB_SIT_CURRENT_NEXT_INDICATOR_MASK, NULL, HFILL
 159         } },
 160
 161         { &hf_dvb_sit_section_number, {
 162             "Section Number", "dvb_sit.sect_num",
 163             FT_UINT8, BASE_DEC, NULL, 0, NULL, HFILL
 164         } },
 165
 166         { &hf_dvb_sit_last_section_number, {
 167             "Last Section Number", "dvb_sit.last_sect_num",
 168             FT_UINT8, BASE_DEC, NULL, 0, NULL, HFILL
 169         } },
 170
 171         { &hf_dvb_sit_reserved_future_use2, {
 172             "Reserved", "dvb_sit.reserved_future_use2",
 173             FT_UINT16, BASE_HEX, NULL, DVB_SIT_RESERVED_FUTURE_USE2_MASK, NULL, HFILL
 174         } },
 175
 176         { &hf_dvb_sit_transmission_info_len, {
 177             "Transmission Info Descriptors Length", "dvb_sit.transmission_info_descriptors_length",
 178             FT_UINT16, BASE_DEC, NULL, DVB_SIT_TRANSMISSION_INFO_MASK, NULL, HFILL
 179         } },
 180
 181         { &hf_dvb_sit_service_id, {
 182             "Service ID", "dvb_sit.svc.id",
 183             FT_UINT16, BASE_HEX, NULL, 0, NULL, HFILL
 184         } },
 185
 186         { &hf_dvb_sit_reserved_future_use3, {
 187             "Reserved", "dvb_sit.svc.reserved_future_use3",
 188             FT_UINT16, BASE_HEX, NULL, DVB_SIT_RESERVED_FUTURE_USE3_MASK, NULL, HFILL
 189         } },
 190
 191         { &hf_dvb_sit_running_status, {
 192             "Running Status", "dvb_sit.svc.running_status",
 193             FT_UINT16, BASE_HEX, VALS(dvb_sit_running_status_vals), DVB_SIT_RUNNING_STATUS_MASK, NULL, HFILL
 194         } },
 195
 196         { &hf_dvb_sit_service_descriptors_length, {
 197             "Service Descriptors Length", "dvb_sit.svc.service_descriptors_length",
 198             FT_UINT16, BASE_DEC, NULL, DVB_SIT_SERVICE_DESCRIPTORS_LENGTH_MASK, NULL, HFILL
 199         } }
 200
 201     };
 202
 203     static int *ett[] = {
 204         &ett_dvb_sit,
 205         &ett_dvb_sit_service
 206     };
 207
 208     proto_dvb_sit = proto_register_protocol("DVB Selection Information Table", "DVB SIT", "dvb_sit");
 209     dvb_sit_handle = register_dissector("dvb_sit", dissect_dvb_sit, proto_dvb_sit);
 210
 211     proto_register_field_array(proto_dvb_sit, hf, array_length(hf));
 212     proto_register_subtree_array(ett, array_length(ett));
 213
 214 }
 215
 216
 217 void proto_reg_handoff_dvb_sit(void)
 218 {
 219     dissector_add_uint("mpeg_sect.tid", DVB_SIT_TID, dvb_sit_handle);
 220 }
 221
 222
 223 /*
 224  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 225  *
 226  * Local variables:
 227  * c-basic-offset: 4
 228  * tab-width: 8
 229  * indent-tabs-mode: nil
 230  * End:
 231  *
 232  * vi: set shiftwidth=4 tabstop=8 expandtab:
 233  * :indentSize=4:tabSize=8:noTabs=true:
 234  */