epan/dissectors/packet-mpeg-ca.c

   1 /* packet-mpeg-ca.c
   2  * Routines for MPEG2 (ISO/ISO 13818-1) Conditional Access Table (CA) 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 <wsutil/array.h>
  17 #include "packet-mpeg-sect.h"
  18 #include "packet-mpeg-descriptor.h"
  19
  20 void proto_register_mpeg_ca(void);
  21 void proto_reg_handoff_mpeg_ca(void);
  22
  23 static dissector_handle_t mpeg_ca_handle;
  24
  25 static int proto_mpeg_ca;
  26 static int hf_mpeg_ca_reserved;
  27 static int hf_mpeg_ca_version_number;
  28 static int hf_mpeg_ca_current_next_indicator;
  29 static int hf_mpeg_ca_section_number;
  30 static int hf_mpeg_ca_last_section_number;
  31
  32 static int ett_mpeg_ca;
  33
  34 #define MPEG_CA_RESERVED_MASK                   0xFFFFC0
  35 #define MPEG_CA_VERSION_NUMBER_MASK             0x00003E
  36 #define MPEG_CA_CURRENT_NEXT_INDICATOR_MASK     0x000001
  37
  38 static int
  39 dissect_mpeg_ca(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
  40 {
  41     unsigned offset = 0, length = 0;
  42
  43     proto_item *ti;
  44     proto_tree *mpeg_ca_tree;
  45
  46     /* The TVB should start right after the section_length in the Section packet */
  47
  48     col_set_str(pinfo->cinfo, COL_INFO, "Conditional Access Table (CA)");
  49
  50     ti = proto_tree_add_item(tree, proto_mpeg_ca, tvb, offset, -1, ENC_NA);
  51     mpeg_ca_tree = proto_item_add_subtree(ti, ett_mpeg_ca);
  52
  53     offset += packet_mpeg_sect_header(tvb, offset, mpeg_ca_tree, &length, NULL);
  54     length -= 4;
  55
  56     proto_tree_add_item(mpeg_ca_tree, hf_mpeg_ca_reserved, tvb, offset, 3, ENC_BIG_ENDIAN);
  57     proto_tree_add_item(mpeg_ca_tree, hf_mpeg_ca_version_number, tvb, offset, 3, ENC_BIG_ENDIAN);
  58     proto_tree_add_item(mpeg_ca_tree, hf_mpeg_ca_current_next_indicator, tvb, offset, 3, ENC_BIG_ENDIAN);
  59     offset += 3;
  60
  61     proto_tree_add_item(mpeg_ca_tree, hf_mpeg_ca_section_number, tvb, offset, 1, ENC_BIG_ENDIAN);
  62     offset += 1;
  63
  64     proto_tree_add_item(mpeg_ca_tree, hf_mpeg_ca_last_section_number, tvb, offset, 1, ENC_BIG_ENDIAN);
  65     offset += 1;
  66
  67     /* Parse all the programs */
  68     while (offset < length)
  69         offset += proto_mpeg_descriptor_dissect(tvb, offset, mpeg_ca_tree);
  70
  71     offset += packet_mpeg_sect_crc(tvb, pinfo, mpeg_ca_tree, 0, offset);
  72
  73     proto_item_set_len(ti, offset);
  74     return tvb_captured_length(tvb);
  75 }
  76
  77
  78 void
  79 proto_register_mpeg_ca(void)
  80 {
  81
  82     static hf_register_info hf[] = {
  83
  84         { &hf_mpeg_ca_reserved, {
  85             "Reserved", "mpeg_ca.reserved",
  86             FT_UINT24, BASE_HEX, NULL, MPEG_CA_RESERVED_MASK,
  87                         NULL, HFILL
  88         } },
  89
  90         { &hf_mpeg_ca_version_number, {
  91             "Version Number", "mpeg_ca.version",
  92             FT_UINT24, BASE_HEX, NULL, MPEG_CA_VERSION_NUMBER_MASK,
  93                         NULL, HFILL
  94         } },
  95
  96         { &hf_mpeg_ca_current_next_indicator, {
  97             "Current/Next Indicator", "mpeg_ca.cur_next_ind",
  98             FT_BOOLEAN, 24, TFS(&tfs_current_not_yet), MPEG_CA_CURRENT_NEXT_INDICATOR_MASK,
  99                         NULL, HFILL
 100         } },
 101
 102         { &hf_mpeg_ca_section_number, {
 103             "Section Number", "mpeg_ca.sect_num",
 104             FT_UINT8, BASE_DEC, NULL, 0,
 105                         NULL, HFILL
 106         } },
 107
 108         { &hf_mpeg_ca_last_section_number, {
 109             "Last Section Number", "mpeg_ca.last_sect_num",
 110             FT_UINT8, BASE_DEC, NULL, 0,
 111                         NULL, HFILL
 112         } },
 113
 114     };
 115
 116     static int *ett[] = {
 117         &ett_mpeg_ca,
 118     };
 119
 120     proto_mpeg_ca = proto_register_protocol("MPEG2 Conditional Access Table", "MPEG CA", "mpeg_ca");
 121
 122     proto_register_field_array(proto_mpeg_ca, hf, array_length(hf));
 123     proto_register_subtree_array(ett, array_length(ett));
 124
 125     mpeg_ca_handle = register_dissector("mpeg_ca", dissect_mpeg_ca, proto_mpeg_ca);
 126 }
 127
 128
 129 void proto_reg_handoff_mpeg_ca(void)
 130 {
 131     dissector_add_uint("mpeg_sect.tid", MPEG_CA_TID, mpeg_ca_handle);
 132 }
 133
 134 /*
 135  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 136  *
 137  * Local variables:
 138  * c-basic-offset: 4
 139  * tab-width: 8
 140  * indent-tabs-mode: nil
 141  * End:
 142  *
 143  * vi: set shiftwidth=4 tabstop=8 expandtab:
 144  * :indentSize=4:tabSize=8:noTabs=true:
 145  */