/src/wireshark/epan/dissectors/packet-dvb-nit.c

Source
/* packet-dvb-nit.c
 * Routines for DVB (ETSI EN 300 468) Network Information Table (NIT) dissection
 * Copyright 2012, Guy Martin <gmsoft@tuxicoman.be>
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <gerald@wireshark.org>
 * Copyright 1998 Gerald Combs
 *
 * SPDX-License-Identifier: GPL-2.0-or-later
 */

#include "config.h"

#include <epan/packet.h>
#include <epan/tfs.h>
#include "packet-mpeg-sect.h"
#include "packet-mpeg-descriptor.h"

void proto_register_dvb_nit(void);
void proto_reg_handoff_dvb_nit(void);

static int proto_dvb_nit;
static int hf_dvb_nit_network_id;
static int hf_dvb_nit_reserved1;
static int hf_dvb_nit_version_number;
static int hf_dvb_nit_current_next_indicator;
static int hf_dvb_nit_section_number;
static int hf_dvb_nit_last_section_number;
static int hf_dvb_nit_reserved2;

static int hf_dvb_nit_network_descriptors_length;
static int hf_dvb_nit_reserved3;
static int hf_dvb_nit_transport_stream_loop_length;

static int hf_dvb_nit_transport_stream_id;
static int hf_dvb_nit_original_network_id;
static int hf_dvb_nit_reserved4;
static int hf_dvb_nit_transport_descriptors_length;

static int ett_dvb_nit;
static int ett_dvb_nit_ts;

static dissector_handle_t dvb_nit_handle;

#define DVB_NIT_RESERVED1_MASK                            0xC0
#define DVB_NIT_VERSION_NUMBER_MASK                       0x3E
#define DVB_NIT_CURRENT_NEXT_INDICATOR_MASK               0x01
#define DVB_NIT_RESERVED2_MASK                          0xF000
#define DVB_NIT_NETWORK_DESCRIPTORS_LENGTH_MASK         0x0FFF
#define DVB_NIT_RESERVED3_MASK                          0xF000
#define DVB_NIT_TRANSPORT_STREAM_LOOP_LENGTH_MASK       0x0FFF
#define DVB_NIT_RESERVED4_MASK                          0xF000
#define DVB_NIT_TRANSPORT_DESCRIPTORS_LENGTH_MASK       0x0FFF

static int
dissect_dvb_nit(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
{

    unsigned    offset = 0;
    unsigned    ts_desc_len, desc_loop_len, ts_end;

    uint16_t    tsid;

    proto_item *ti;
    proto_tree *dvb_nit_tree;
    proto_tree *dvb_nit_ts_tree;

    col_set_str(pinfo->cinfo, COL_INFO, "Network Information Table (NIT)");

    ti = proto_tree_add_item(tree, proto_dvb_nit, tvb, offset, -1, ENC_NA);
    dvb_nit_tree = proto_item_add_subtree(ti, ett_dvb_nit);

    offset += packet_mpeg_sect_header(tvb, offset, dvb_nit_tree, NULL, NULL);

    proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_network_id,                 tvb, offset, 2, ENC_BIG_ENDIAN);
    offset += 2;

    proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_reserved1,                  tvb, offset, 1, ENC_BIG_ENDIAN);
    proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_version_number,             tvb, offset, 1, ENC_BIG_ENDIAN);
    proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_current_next_indicator,     tvb, offset, 1, ENC_BIG_ENDIAN);
    offset += 1;

    proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_section_number,             tvb, offset, 1, ENC_BIG_ENDIAN);
    offset += 1;

    proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_last_section_number,        tvb, offset, 1, ENC_BIG_ENDIAN);
    offset += 1;

    proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_reserved2,                  tvb, offset, 2, ENC_BIG_ENDIAN);
    proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_network_descriptors_length, tvb, offset, 2, ENC_BIG_ENDIAN);
    desc_loop_len = tvb_get_ntohs(tvb, offset) & DVB_NIT_NETWORK_DESCRIPTORS_LENGTH_MASK;
    offset += 2;

    offset += proto_mpeg_descriptor_loop_dissect(tvb, pinfo, offset, desc_loop_len, dvb_nit_tree);

    proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_reserved3,                    tvb, offset, 2, ENC_BIG_ENDIAN);
    proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_transport_stream_loop_length, tvb, offset, 2, ENC_BIG_ENDIAN);
    ts_end = offset + (tvb_get_ntohs(tvb, offset) & DVB_NIT_TRANSPORT_STREAM_LOOP_LENGTH_MASK);
    offset += 2;

    while (offset < ts_end) {
        tsid = tvb_get_ntohs(tvb, offset);
        ts_desc_len = 3 + (tvb_get_ntohs(tvb, offset + 4) & DVB_NIT_TRANSPORT_DESCRIPTORS_LENGTH_MASK);

        dvb_nit_ts_tree = proto_tree_add_subtree_format(dvb_nit_tree, tvb, offset, ts_desc_len,
                               ett_dvb_nit_ts, NULL, "Stream ID=0x%04hx", tsid);

        proto_tree_add_item(dvb_nit_ts_tree, hf_dvb_nit_transport_stream_id, tvb, offset, 2, ENC_BIG_ENDIAN);
        offset += 2;

        proto_tree_add_item(dvb_nit_ts_tree, hf_dvb_nit_original_network_id, tvb, offset, 2, ENC_BIG_ENDIAN);
        offset += 2;

        proto_tree_add_item(dvb_nit_ts_tree, hf_dvb_nit_reserved4,                    tvb, offset, 2, ENC_BIG_ENDIAN);
        proto_tree_add_item(dvb_nit_ts_tree, hf_dvb_nit_transport_descriptors_length, tvb, offset, 2, ENC_BIG_ENDIAN);
        desc_loop_len = tvb_get_ntohs(tvb, offset) & DVB_NIT_TRANSPORT_DESCRIPTORS_LENGTH_MASK;
        offset += 2;

        offset += proto_mpeg_descriptor_loop_dissect(tvb, pinfo, offset, desc_loop_len, dvb_nit_ts_tree);
    }

    offset += packet_mpeg_sect_crc(tvb, pinfo, dvb_nit_tree, 0, offset);

    proto_item_set_len(ti, offset);
    return offset;
}


void
proto_register_dvb_nit(void)
{

    static hf_register_info hf[] = {

        { &hf_dvb_nit_network_id, {
            "Network ID", "dvb_nit.sid",
            FT_UINT16, BASE_HEX, NULL, 0, NULL, HFILL
        } },

        { &hf_dvb_nit_reserved1, {
            "Reserved", "dvb_nit.reserved1",
            FT_UINT8, BASE_HEX, NULL, DVB_NIT_RESERVED1_MASK, NULL, HFILL
        } },

        { &hf_dvb_nit_version_number, {
            "Version Number", "dvb_nit.version",
            FT_UINT8, BASE_HEX, NULL, DVB_NIT_VERSION_NUMBER_MASK, NULL, HFILL
        } },

        { &hf_dvb_nit_current_next_indicator, {
            "Current/Next Indicator", "dvb_nit.cur_next_ind",
            FT_BOOLEAN, 8, TFS(&tfs_current_not_yet), DVB_NIT_CURRENT_NEXT_INDICATOR_MASK, NULL, HFILL
        } },

        { &hf_dvb_nit_section_number, {
            "Section Number", "dvb_nit.sect_num",
            FT_UINT8, BASE_DEC, NULL, 0, NULL, HFILL
        } },

        { &hf_dvb_nit_last_section_number, {
            "Last Section Number", "dvb_nit.last_sect_num",
            FT_UINT8, BASE_DEC, NULL, 0, NULL, HFILL
        } },

        { &hf_dvb_nit_reserved2, {
            "Reserved", "dvb_nit.reserved2",
            FT_UINT16, BASE_HEX, NULL, DVB_NIT_RESERVED2_MASK, NULL, HFILL
        } },

        { &hf_dvb_nit_network_descriptors_length, {
            "Network Descriptors Length", "dvb_nit.network_desc_len",
            FT_UINT16, BASE_DEC, NULL, DVB_NIT_NETWORK_DESCRIPTORS_LENGTH_MASK, NULL, HFILL
        } },

        { &hf_dvb_nit_reserved3, {
            "Reserved", "dvb_nit.reserved3",
            FT_UINT16, BASE_HEX, NULL, DVB_NIT_RESERVED3_MASK, NULL, HFILL
        } },

        { &hf_dvb_nit_transport_stream_loop_length, {
            "Transport Stream Loop Length", "dvb_nit.ts_loop_len",
            FT_UINT16, BASE_DEC, NULL, DVB_NIT_TRANSPORT_STREAM_LOOP_LENGTH_MASK, NULL, HFILL
        } },

        { &hf_dvb_nit_transport_stream_id, {
            "Transport Stream ID", "dvb_nit.ts.id",
            FT_UINT16, BASE_HEX, NULL, 0, NULL, HFILL
        } },

        { &hf_dvb_nit_original_network_id, {
            "Original Network ID", "dvb_nit.ts.original_network_id",
            FT_UINT16, BASE_HEX, NULL, 0, NULL, HFILL
        } },

        { &hf_dvb_nit_reserved4, {
            "Reserved", "dvb_nit.ts.reserved",
            FT_UINT16, BASE_HEX, NULL, DVB_NIT_RESERVED4_MASK, NULL, HFILL
        } },

        { &hf_dvb_nit_transport_descriptors_length, {
            "Transport Descriptors Length", "dvb_nit.ts.desc_len",
            FT_UINT16, BASE_DEC, NULL, DVB_NIT_TRANSPORT_DESCRIPTORS_LENGTH_MASK, NULL, HFILL
        } },

    };

    static int *ett[] = {
        &ett_dvb_nit,
        &ett_dvb_nit_ts
    };

    proto_dvb_nit = proto_register_protocol("DVB Network Information Table", "DVB NIT", "dvb_nit");

    proto_register_field_array(proto_dvb_nit, hf, array_length(hf));
    proto_register_subtree_array(ett, array_length(ett));

    dvb_nit_handle = register_dissector("dvb_nit", dissect_dvb_nit, proto_dvb_nit);
}


void proto_reg_handoff_dvb_nit(void)
{
    dissector_add_uint("mpeg_sect.tid", DVB_NIT_TID, dvb_nit_handle);
    dissector_add_uint("mpeg_sect.tid", DVB_NIT_TID_OTHER, dvb_nit_handle);
}


/*
 * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 *
 * Local variables:
 * c-basic-offset: 4
 * tab-width: 8
 * indent-tabs-mode: nil
 * End:
 *
 * vi: set shiftwidth=4 tabstop=8 expandtab:
 * :indentSize=4:tabSize=8:noTabs=true:
 */

Coverage Report

Created: 2025-08-04 07:15

Line	Count	Source
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	14	#define DVB_NIT_RESERVED1_MASK 0xC0
46	14	#define DVB_NIT_VERSION_NUMBER_MASK 0x3E
47	14	#define DVB_NIT_CURRENT_NEXT_INDICATOR_MASK 0x01
48	14	#define DVB_NIT_RESERVED2_MASK 0xF000
49	30	#define DVB_NIT_NETWORK_DESCRIPTORS_LENGTH_MASK 0x0FFF
50	14	#define DVB_NIT_RESERVED3_MASK 0xF000
51	30	#define DVB_NIT_TRANSPORT_STREAM_LOOP_LENGTH_MASK 0x0FFF
52	14	#define DVB_NIT_RESERVED4_MASK 0xF000
53	32	#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	16	{
58
59	16	unsigned offset = 0;
60	16	unsigned ts_desc_len, desc_loop_len, ts_end;
61
62	16	uint16_t tsid;
63
64	16	proto_item *ti;
65	16	proto_tree *dvb_nit_tree;
66	16	proto_tree *dvb_nit_ts_tree;
67
68	16	col_set_str(pinfo->cinfo, COL_INFO, "Network Information Table (NIT)");
69
70	16	ti = proto_tree_add_item(tree, proto_dvb_nit, tvb, offset, -1, ENC_NA);
71	16	dvb_nit_tree = proto_item_add_subtree(ti, ett_dvb_nit);
72
73	16	offset += packet_mpeg_sect_header(tvb, offset, dvb_nit_tree, NULL, NULL);
74
75	16	proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_network_id, tvb, offset, 2, ENC_BIG_ENDIAN);
76	16	offset += 2;
77
78	16	proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_reserved1, tvb, offset, 1, ENC_BIG_ENDIAN);
79	16	proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_version_number, tvb, offset, 1, ENC_BIG_ENDIAN);
80	16	proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_current_next_indicator, tvb, offset, 1, ENC_BIG_ENDIAN);
81	16	offset += 1;
82
83	16	proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_section_number, tvb, offset, 1, ENC_BIG_ENDIAN);
84	16	offset += 1;
85
86	16	proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_last_section_number, tvb, offset, 1, ENC_BIG_ENDIAN);
87	16	offset += 1;
88
89	16	proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_reserved2, tvb, offset, 2, ENC_BIG_ENDIAN);
90	16	proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_network_descriptors_length, tvb, offset, 2, ENC_BIG_ENDIAN);
91	16	desc_loop_len = tvb_get_ntohs(tvb, offset) & DVB_NIT_NETWORK_DESCRIPTORS_LENGTH_MASK;
92	16	offset += 2;
93
94	16	offset += proto_mpeg_descriptor_loop_dissect(tvb, pinfo, offset, desc_loop_len, dvb_nit_tree);
95
96	16	proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_reserved3, tvb, offset, 2, ENC_BIG_ENDIAN);
97	16	proto_tree_add_item(dvb_nit_tree, hf_dvb_nit_transport_stream_loop_length, tvb, offset, 2, ENC_BIG_ENDIAN);
98	16	ts_end = offset + (tvb_get_ntohs(tvb, offset) & DVB_NIT_TRANSPORT_STREAM_LOOP_LENGTH_MASK);
99	16	offset += 2;
100
101	25	while (offset < ts_end) {
102	9	tsid = tvb_get_ntohs(tvb, offset);
103	9	ts_desc_len = 3 + (tvb_get_ntohs(tvb, offset + 4) & DVB_NIT_TRANSPORT_DESCRIPTORS_LENGTH_MASK);
104
105	9	dvb_nit_ts_tree = proto_tree_add_subtree_format(dvb_nit_tree, tvb, offset, ts_desc_len,
106	9	ett_dvb_nit_ts, NULL, "Stream ID=0x%04hx", tsid);
107
108	9	proto_tree_add_item(dvb_nit_ts_tree, hf_dvb_nit_transport_stream_id, tvb, offset, 2, ENC_BIG_ENDIAN);
109	9	offset += 2;
110
111	9	proto_tree_add_item(dvb_nit_ts_tree, hf_dvb_nit_original_network_id, tvb, offset, 2, ENC_BIG_ENDIAN);
112	9	offset += 2;
113
114	9	proto_tree_add_item(dvb_nit_ts_tree, hf_dvb_nit_reserved4, tvb, offset, 2, ENC_BIG_ENDIAN);
115	9	proto_tree_add_item(dvb_nit_ts_tree, hf_dvb_nit_transport_descriptors_length, tvb, offset, 2, ENC_BIG_ENDIAN);
116	9	desc_loop_len = tvb_get_ntohs(tvb, offset) & DVB_NIT_TRANSPORT_DESCRIPTORS_LENGTH_MASK;
117	9	offset += 2;
118
119	9	offset += proto_mpeg_descriptor_loop_dissect(tvb, pinfo, offset, desc_loop_len, dvb_nit_ts_tree);
120	9	}
121
122	16	offset += packet_mpeg_sect_crc(tvb, pinfo, dvb_nit_tree, 0, offset);
123
124	16	proto_item_set_len(ti, offset);
125	16	return offset;
126	16	}
127
128
129		void
130		proto_register_dvb_nit(void)
131	14	{
132
133	14	static hf_register_info hf[] = {
134
135	14	{ &hf_dvb_nit_network_id, {
136	14	"Network ID", "dvb_nit.sid",
137	14	FT_UINT16, BASE_HEX, NULL, 0, NULL, HFILL
138	14	} },
139
140	14	{ &hf_dvb_nit_reserved1, {
141	14	"Reserved", "dvb_nit.reserved1",
142	14	FT_UINT8, BASE_HEX, NULL, DVB_NIT_RESERVED1_MASK, NULL, HFILL
143	14	} },
144
145	14	{ &hf_dvb_nit_version_number, {
146	14	"Version Number", "dvb_nit.version",
147	14	FT_UINT8, BASE_HEX, NULL, DVB_NIT_VERSION_NUMBER_MASK, NULL, HFILL
148	14	} },
149
150	14	{ &hf_dvb_nit_current_next_indicator, {
151	14	"Current/Next Indicator", "dvb_nit.cur_next_ind",
152	14	FT_BOOLEAN, 8, TFS(&tfs_current_not_yet), DVB_NIT_CURRENT_NEXT_INDICATOR_MASK, NULL, HFILL
153	14	} },
154
155	14	{ &hf_dvb_nit_section_number, {
156	14	"Section Number", "dvb_nit.sect_num",
157	14	FT_UINT8, BASE_DEC, NULL, 0, NULL, HFILL
158	14	} },
159
160	14	{ &hf_dvb_nit_last_section_number, {
161	14	"Last Section Number", "dvb_nit.last_sect_num",
162	14	FT_UINT8, BASE_DEC, NULL, 0, NULL, HFILL
163	14	} },
164
165	14	{ &hf_dvb_nit_reserved2, {
166	14	"Reserved", "dvb_nit.reserved2",
167	14	FT_UINT16, BASE_HEX, NULL, DVB_NIT_RESERVED2_MASK, NULL, HFILL
168	14	} },
169
170	14	{ &hf_dvb_nit_network_descriptors_length, {
171	14	"Network Descriptors Length", "dvb_nit.network_desc_len",
172	14	FT_UINT16, BASE_DEC, NULL, DVB_NIT_NETWORK_DESCRIPTORS_LENGTH_MASK, NULL, HFILL
173	14	} },
174
175	14	{ &hf_dvb_nit_reserved3, {
176	14	"Reserved", "dvb_nit.reserved3",
177	14	FT_UINT16, BASE_HEX, NULL, DVB_NIT_RESERVED3_MASK, NULL, HFILL
178	14	} },
179
180	14	{ &hf_dvb_nit_transport_stream_loop_length, {
181	14	"Transport Stream Loop Length", "dvb_nit.ts_loop_len",
182	14	FT_UINT16, BASE_DEC, NULL, DVB_NIT_TRANSPORT_STREAM_LOOP_LENGTH_MASK, NULL, HFILL
183	14	} },
184
185	14	{ &hf_dvb_nit_transport_stream_id, {
186	14	"Transport Stream ID", "dvb_nit.ts.id",
187	14	FT_UINT16, BASE_HEX, NULL, 0, NULL, HFILL
188	14	} },
189
190	14	{ &hf_dvb_nit_original_network_id, {
191	14	"Original Network ID", "dvb_nit.ts.original_network_id",
192	14	FT_UINT16, BASE_HEX, NULL, 0, NULL, HFILL
193	14	} },
194
195	14	{ &hf_dvb_nit_reserved4, {
196	14	"Reserved", "dvb_nit.ts.reserved",
197	14	FT_UINT16, BASE_HEX, NULL, DVB_NIT_RESERVED4_MASK, NULL, HFILL
198	14	} },
199
200	14	{ &hf_dvb_nit_transport_descriptors_length, {
201	14	"Transport Descriptors Length", "dvb_nit.ts.desc_len",
202	14	FT_UINT16, BASE_DEC, NULL, DVB_NIT_TRANSPORT_DESCRIPTORS_LENGTH_MASK, NULL, HFILL
203	14	} },
204
205	14	};
206
207	14	static int *ett[] = {
208	14	&ett_dvb_nit,
209	14	&ett_dvb_nit_ts
210	14	};
211
212	14	proto_dvb_nit = proto_register_protocol("DVB Network Information Table", "DVB NIT", "dvb_nit");
213
214	14	proto_register_field_array(proto_dvb_nit, hf, array_length(hf));
215	14	proto_register_subtree_array(ett, array_length(ett));
216
217	14	dvb_nit_handle = register_dissector("dvb_nit", dissect_dvb_nit, proto_dvb_nit);
218	14	}
219
220
221		void proto_reg_handoff_dvb_nit(void)
222	14	{
223	14	dissector_add_uint("mpeg_sect.tid", DVB_NIT_TID, dvb_nit_handle);
224	14	dissector_add_uint("mpeg_sect.tid", DVB_NIT_TID_OTHER, dvb_nit_handle);
225	14	}
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		*/