diff options
Diffstat (limited to 'epan/dissectors/asn1/mpeg-audio/packet-mpeg-audio-template.c')
| -rw-r--r-- | epan/dissectors/asn1/mpeg-audio/packet-mpeg-audio-template.c | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/epan/dissectors/asn1/mpeg-audio/packet-mpeg-audio-template.c b/epan/dissectors/asn1/mpeg-audio/packet-mpeg-audio-template.c new file mode 100644 index 0000000000..ce7cc90d35 --- /dev/null +++ b/epan/dissectors/asn1/mpeg-audio/packet-mpeg-audio-template.c @@ -0,0 +1,178 @@ +/* MPEG audio packet decoder. + * Written by Shaun Jackman <sjackman@gmail.com>. + * Copyright 2007 Shaun Jackman + * + * Wireshark - Network traffic analyzer + * By Gerald Combs <gerald@wireshark.org> + * + * 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 <epan/asn1.h> + +#include <wsutil/mpeg-audio.h> + +#include "packet-per.h" + +#include "packet-mpeg-audio-hf.c" +#include "packet-mpeg-audio-ett.c" +#include "packet-mpeg-audio-fn.c" + +void proto_register_mpeg_audio(void); +void proto_reg_handoff_mpeg_audio(void); + +static int proto_mpeg_audio = -1; + +static int hf_mpeg_audio_data = -1; +static int hf_mpeg_audio_padbytes = -1; +static int hf_id3v1 = -1; +static int hf_id3v2 = -1; + +static gboolean +dissect_mpeg_audio_frame(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) +{ + guint32 h; + struct mpa mpa; + int data_size = 0; + asn1_ctx_t asn1_ctx; + int offset = 0; + static const char *version_names[] = { "1", "2", "2.5" }; + + if (!tvb_bytes_exist(tvb, 0, 4)) + return FALSE; /* not enough data for an MPEG audio frame */ + + h = tvb_get_ntohl(tvb, 0); + MPA_UNMARSHAL(&mpa, h); + if (!MPA_SYNC_VALID(&mpa)) + return FALSE; + if (!MPA_VERSION_VALID(&mpa)) + return FALSE; + if (!MPA_LAYER_VALID(&mpa)) + return FALSE; + + col_add_fstr(pinfo->cinfo, COL_PROTOCOL, + "MPEG-%s", version_names[mpa_version(&mpa)]); + col_add_fstr(pinfo->cinfo, COL_INFO, + "Audio Layer %d", mpa_layer(&mpa) + 1); + if (MPA_BITRATE_VALID(&mpa) && MPA_FREQUENCY_VALID(&mpa)) { + data_size = (int)(MPA_DATA_BYTES(&mpa) - sizeof mpa); + col_append_fstr(pinfo->cinfo, COL_INFO, + ", %d kb/s, %g kHz", + mpa_bitrate(&mpa) / 1000, + mpa_frequency(&mpa) / (float)1000); + } + + if (tree == NULL) + return TRUE; + + asn1_ctx_init(&asn1_ctx, ASN1_ENC_PER, TRUE, pinfo); + offset = dissect_mpeg_audio_Audio(tvb, offset, &asn1_ctx, + tree, proto_mpeg_audio); + if (data_size > 0) { + unsigned int padding; + + proto_tree_add_item(tree, hf_mpeg_audio_data, tvb, + offset / 8, data_size, ENC_NA); + offset += data_size * 8; + padding = mpa_padding(&mpa); + if (padding > 0) { + proto_tree_add_item(tree, hf_mpeg_audio_padbytes, tvb, + offset / 8, padding, ENC_NA); + } + } + return TRUE; +} + +static void +dissect_id3v1(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) +{ + asn1_ctx_t asn1_ctx; + + col_set_str(pinfo->cinfo, COL_PROTOCOL, "ID3v1"); + col_clear(pinfo->cinfo, COL_INFO); + if (tree == NULL) + return; + asn1_ctx_init(&asn1_ctx, ASN1_ENC_PER, TRUE, pinfo); + dissect_mpeg_audio_ID3v1(tvb, 0, &asn1_ctx, + tree, hf_id3v1); +} + +static void +dissect_id3v2(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) +{ + col_set_str(pinfo->cinfo, COL_PROTOCOL, "ID3v2"); + col_clear(pinfo->cinfo, COL_INFO); + proto_tree_add_item(tree, hf_id3v2, tvb, + 0, -1, ENC_NA); +} + +static gboolean +dissect_mpeg_audio(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_) +{ + int magic; + + if (!tvb_bytes_exist(tvb, 0, 3)) + return FALSE; /* not enough data for an ID tag or audio frame */ + magic = tvb_get_ntoh24(tvb, 0); + switch (magic) { + case 0x544147: /* TAG */ + dissect_id3v1(tvb, pinfo, tree); + return TRUE; + case 0x494433: /* ID3 */ + dissect_id3v2(tvb, pinfo, tree); + return TRUE; + default: + return dissect_mpeg_audio_frame(tvb, pinfo, tree); + } +} + +void +proto_register_mpeg_audio(void) +{ + static hf_register_info hf[] = { +#include "packet-mpeg-audio-hfarr.c" + { &hf_mpeg_audio_data, + { "Data", "mpeg-audio.data", + FT_BYTES, BASE_NONE, NULL, 0, NULL, HFILL }}, + { &hf_mpeg_audio_padbytes, + { "Padding", "mpeg-audio.padbytes", + FT_BYTES, BASE_NONE, NULL, 0, NULL, HFILL }}, + + { &hf_id3v1, + { "ID3v1", "mpeg-audio.id3v1", + FT_NONE, BASE_NONE, NULL, 0, NULL, HFILL }}, + { &hf_id3v2, + { "ID3v2", "mpeg-audio.id3v2", + FT_NONE, BASE_NONE, NULL, 0, NULL, HFILL }}, + }; + + static gint *ett[] = { +#include "packet-mpeg-audio-ettarr.c" + }; + + proto_mpeg_audio = proto_register_protocol( + "Moving Picture Experts Group Audio", "MPEG Audio", "mpeg-audio"); + proto_register_field_array(proto_mpeg_audio, hf, array_length(hf)); + proto_register_subtree_array(ett, array_length(ett)); +} + +void +proto_reg_handoff_mpeg_audio(void) +{ + heur_dissector_add("mpeg", dissect_mpeg_audio, "MPEG Audio", "mpeg_audio", proto_mpeg_audio, HEURISTIC_ENABLE); +} |