wireshark/epan/dissectors/packet-dvb-nit.c
Michael Mann f4b0abc729 Dissectors don't need a journey of self discovery.
They already know who they are when they register themselves.  Saving the
handle then to avoid finding it later.
Not sure if this will increase unnecessary register_dissector functions
(instead of using create_dissector_handle in proto_reg_handoff function)
when other dissectors copy/paste, but it should make startup time
a few microseconds better.

Change-Id: I3839be791b32b84887ac51a6a65fb5733e9f1f43
Reviewed-on: https://code.wireshark.org/review/19481
Petri-Dish: Michael Mann <mmann78@netscape.net>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Anders Broman <a.broman58@gmail.com>
2016-12-31 07:31:42 +00:00

259 lines
9.3 KiB
C

/* 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
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "config.h"
#include <epan/packet.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 = -1;
static int hf_dvb_nit_network_id = -1;
static int hf_dvb_nit_reserved1 = -1;
static int hf_dvb_nit_version_number = -1;
static int hf_dvb_nit_current_next_indicator = -1;
static int hf_dvb_nit_section_number = -1;
static int hf_dvb_nit_last_section_number = -1;
static int hf_dvb_nit_reserved2 = -1;
static int hf_dvb_nit_network_descriptors_length = -1;
static int hf_dvb_nit_reserved3 = -1;
static int hf_dvb_nit_transport_stream_loop_length = -1;
static int hf_dvb_nit_transport_stream_id = -1;
static int hf_dvb_nit_original_network_id = -1;
static int hf_dvb_nit_reserved4 = -1;
static int hf_dvb_nit_transport_descriptors_length = -1;
static gint ett_dvb_nit = -1;
static gint ett_dvb_nit_ts = -1;
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 const value_string dvb_nit_cur_next_vals[] = {
{ 0, "Not yet applicable" },
{ 1, "Currently applicable" },
{ 0, NULL }
};
static int
dissect_dvb_nit(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
{
guint offset = 0;
guint ts_desc_len, desc_loop_len, ts_end;
guint16 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, 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, 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_UINT8, BASE_DEC, VALS(dvb_nit_cur_next_vals), 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 gint *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 - http://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:
*/