2 * Sony OpenMG (OMA) demuxer
4 * Copyright (c) 2008 Maxim Poliakovski
5 * 2008 Benjamin Larsson
8 * This file is part of Libav.
10 * Libav is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU Lesser General Public
12 * License as published by the Free Software Foundation; either
13 * version 2.1 of the License, or (at your option) any later version.
15 * Libav is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * Lesser General Public License for more details.
20 * You should have received a copy of the GNU Lesser General Public
21 * License along with Libav; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
27 * This is a demuxer for Sony OpenMG Music files
29 * Known file extensions: ".oma", "aa3"
30 * The format of such files consists of three parts:
31 * - "ea3" header carrying overall info and metadata. Except for starting with
32 * "ea" instead of "ID", it's an ID3v2 header.
33 * - "EA3" header is a Sony-specific header containing information about
34 * the OpenMG file: codec type (usually ATRAC, can also be MP3 or WMA),
35 * codec specific info (packet size, sample rate, channels and so on)
36 * and DRM related info (file encryption, content id).
37 * - Sound data organized in packets follow the EA3 header
38 * (can be encrypted using the Sony DRM!).
40 * CODEC SUPPORT: Only ATRAC3 codec is currently supported!
45 #include "libavutil/intreadwrite.h"
46 #include "libavutil/des.h"
51 #define EA3_HEADER_SIZE 96
52 #define ID3v2_EA3_MAGIC "ea3"
53 #define OMA_ENC_HEADER_SIZE 16
56 OMA_CODECID_ATRAC3 = 0,
57 OMA_CODECID_ATRAC3P = 1,
63 static const AVCodecTag codec_oma_tags[] = {
64 { CODEC_ID_ATRAC3, OMA_CODECID_ATRAC3 },
65 { CODEC_ID_ATRAC3P, OMA_CODECID_ATRAC3P },
66 { CODEC_ID_MP3, OMA_CODECID_MP3 },
67 { CODEC_ID_PCM_S16BE, OMA_CODECID_LPCM },
70 static const uint64_t leaf_table[] = {
71 0xd79e8283acea4620, 0x7a9762f445afd0d8,
72 0x354d60a60b8c79f1, 0x584e1cde00b07aee,
73 0x1573cd93da7df623, 0x47f98d79620dd535
76 typedef struct OMAContext {
77 uint64_t content_start;
94 static void hex_log(AVFormatContext *s, int level, const char *name, const uint8_t *value, int len)
98 if (av_log_get_level() < level)
100 ff_data_to_hex(buf, value, len, 1);
102 av_log(s, level, "%s: %s\n", name, buf);
105 static int kset(AVFormatContext *s, const uint8_t *r_val, const uint8_t *n_val, int len)
107 OMAContext *oc = s->priv_data;
109 if (!r_val && !n_val)
112 len = FFMIN(len, 16);
114 /* use first 64 bits in the third round again */
116 if (r_val != oc->r_val) {
117 memset(oc->r_val, 0, 24);
118 memcpy(oc->r_val, r_val, len);
120 memcpy(&oc->r_val[16], r_val, 8);
123 if (n_val != oc->n_val) {
124 memset(oc->n_val, 0, 24);
125 memcpy(oc->n_val, n_val, len);
127 memcpy(&oc->n_val[16], n_val, 8);
133 static int rprobe(AVFormatContext *s, uint8_t *enc_header, const uint8_t *r_val)
135 OMAContext *oc = s->priv_data;
139 if (!enc_header || !r_val)
143 av_des_init(&av_des, r_val, 192, 1);
144 av_des_crypt(&av_des, oc->m_val, &enc_header[48], 1, NULL, 1);
147 av_des_init(&av_des, oc->m_val, 64, 0);
148 av_des_crypt(&av_des, oc->s_val, NULL, 1, NULL, 0);
151 pos = OMA_ENC_HEADER_SIZE + oc->k_size + oc->e_size;
152 av_des_init(&av_des, oc->s_val, 64, 0);
153 av_des_mac(&av_des, oc->sm_val, &enc_header[pos], (oc->i_size >> 3));
157 return memcmp(&enc_header[pos], oc->sm_val, 8) ? -1 : 0;
160 static int nprobe(AVFormatContext *s, uint8_t *enc_header, const uint8_t *n_val)
162 OMAContext *oc = s->priv_data;
163 uint32_t pos, taglen, datalen;
166 if (!enc_header || !n_val)
169 pos = OMA_ENC_HEADER_SIZE + oc->k_size;
170 if (!memcmp(&enc_header[pos], "EKB ", 4))
173 if (AV_RB32(&enc_header[pos]) != oc->rid)
174 av_log(s, AV_LOG_DEBUG, "Mismatching RID\n");
176 taglen = AV_RB32(&enc_header[pos+32]);
177 datalen = AV_RB32(&enc_header[pos+36]) >> 4;
181 av_des_init(&av_des, n_val, 192, 1);
182 while (datalen-- > 0) {
183 av_des_crypt(&av_des, oc->r_val, &enc_header[pos], 2, NULL, 1);
184 kset(s, oc->r_val, NULL, 16);
185 if (!rprobe(s, enc_header, oc->r_val))
193 static int decrypt_init(AVFormatContext *s, ID3v2ExtraMeta *em, uint8_t *header)
195 OMAContext *oc = s->priv_data;
196 ID3v2ExtraMetaGEOB *geob = NULL;
200 av_log(s, AV_LOG_INFO, "File is encrypted\n");
202 /* find GEOB metadata */
204 if (!strcmp(em->tag, "GEOB") &&
206 (!strcmp(geob->description, "OMG_LSI") ||
207 !strcmp(geob->description, "OMG_BKLSI"))) {
213 av_log(s, AV_LOG_ERROR, "No encryption header found\n");
217 if (geob->datasize < 64) {
218 av_log(s, AV_LOG_ERROR, "Invalid GEOB data size: %u\n", geob->datasize);
224 if (AV_RB16(gdata) != 1)
225 av_log(s, AV_LOG_WARNING, "Unknown version in encryption header\n");
227 oc->k_size = AV_RB16(&gdata[2]);
228 oc->e_size = AV_RB16(&gdata[4]);
229 oc->i_size = AV_RB16(&gdata[6]);
230 oc->s_size = AV_RB16(&gdata[8]);
232 if (memcmp(&gdata[OMA_ENC_HEADER_SIZE], "KEYRING ", 12)) {
233 av_log(s, AV_LOG_ERROR, "Invalid encryption header\n");
236 oc->rid = AV_RB32(&gdata[OMA_ENC_HEADER_SIZE + 28]);
237 av_log(s, AV_LOG_DEBUG, "RID: %.8x\n", oc->rid);
239 memcpy(oc->iv, &header[0x58], 8);
240 hex_log(s, AV_LOG_DEBUG, "IV", oc->iv, 8);
242 hex_log(s, AV_LOG_DEBUG, "CBC-MAC", &gdata[OMA_ENC_HEADER_SIZE+oc->k_size+oc->e_size+oc->i_size], 8);
245 kset(s, s->key, s->key, s->keylen);
247 if (!memcmp(oc->r_val, (const uint8_t[8]){0}, 8) ||
248 rprobe(s, gdata, oc->r_val) < 0 &&
249 nprobe(s, gdata, oc->n_val) < 0) {
251 for (i = 0; i < sizeof(leaf_table); i += 2) {
253 AV_WL64(buf, leaf_table[i]);
254 AV_WL64(&buf[8], leaf_table[i+1]);
255 kset(s, buf, buf, 16);
256 if (!rprobe(s, gdata, oc->r_val) || !nprobe(s, gdata, oc->n_val))
259 if (i >= sizeof(leaf_table)) {
260 av_log(s, AV_LOG_ERROR, "Invalid key\n");
266 av_des_init(&oc->av_des, oc->m_val, 64, 0);
267 av_des_crypt(&oc->av_des, oc->e_val, &gdata[OMA_ENC_HEADER_SIZE + 40], 1, NULL, 0);
268 hex_log(s, AV_LOG_DEBUG, "EK", oc->e_val, 8);
271 av_des_init(&oc->av_des, oc->e_val, 64, 1);
276 static int oma_read_header(AVFormatContext *s,
277 AVFormatParameters *ap)
279 static const uint16_t srate_tab[6] = {320,441,480,882,960,0};
280 int ret, framesize, jsflag, samplerate;
281 uint32_t codec_params;
283 uint8_t buf[EA3_HEADER_SIZE];
286 ID3v2ExtraMeta *extra_meta = NULL;
287 OMAContext *oc = s->priv_data;
289 ff_id3v2_read_all(s, ID3v2_EA3_MAGIC, &extra_meta);
290 ret = avio_read(s->pb, buf, EA3_HEADER_SIZE);
291 if (ret < EA3_HEADER_SIZE)
294 if (memcmp(buf, ((const uint8_t[]){'E', 'A', '3'}),3) || buf[4] != 0 || buf[5] != EA3_HEADER_SIZE) {
295 av_log(s, AV_LOG_ERROR, "Couldn't find the EA3 header !\n");
299 oc->content_start = avio_tell(s->pb);
302 eid = AV_RB16(&buf[6]);
303 if (eid != -1 && eid != -128 && decrypt_init(s, extra_meta, buf) < 0) {
304 ff_id3v2_free_extra_meta(&extra_meta);
308 ff_id3v2_free_extra_meta(&extra_meta);
310 codec_params = AV_RB24(&buf[33]);
312 st = avformat_new_stream(s, NULL);
314 return AVERROR(ENOMEM);
317 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
318 st->codec->codec_tag = buf[32];
319 st->codec->codec_id = ff_codec_get_id(codec_oma_tags, st->codec->codec_tag);
322 case OMA_CODECID_ATRAC3:
323 samplerate = srate_tab[(codec_params >> 13) & 7]*100;
324 if (samplerate != 44100)
325 av_log_ask_for_sample(s, "Unsupported sample rate: %d\n",
328 framesize = (codec_params & 0x3FF) * 8;
329 jsflag = (codec_params >> 17) & 1; /* get stereo coding mode, 1 for joint-stereo */
330 st->codec->channels = 2;
331 st->codec->sample_rate = samplerate;
332 st->codec->bit_rate = st->codec->sample_rate * framesize * 8 / 1024;
334 /* fake the atrac3 extradata (wav format, makes stream copy to wav work) */
335 st->codec->extradata_size = 14;
336 edata = av_mallocz(14 + FF_INPUT_BUFFER_PADDING_SIZE);
338 return AVERROR(ENOMEM);
340 st->codec->extradata = edata;
341 AV_WL16(&edata[0], 1); // always 1
342 AV_WL32(&edata[2], samplerate); // samples rate
343 AV_WL16(&edata[6], jsflag); // coding mode
344 AV_WL16(&edata[8], jsflag); // coding mode
345 AV_WL16(&edata[10], 1); // always 1
346 // AV_WL16(&edata[12], 0); // always 0
348 avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
350 case OMA_CODECID_ATRAC3P:
351 st->codec->channels = (codec_params >> 10) & 7;
352 framesize = ((codec_params & 0x3FF) * 8) + 8;
353 st->codec->sample_rate = srate_tab[(codec_params >> 13) & 7]*100;
354 st->codec->bit_rate = st->codec->sample_rate * framesize * 8 / 1024;
355 avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
356 av_log(s, AV_LOG_ERROR, "Unsupported codec ATRAC3+!\n");
358 case OMA_CODECID_MP3:
359 st->need_parsing = AVSTREAM_PARSE_FULL;
362 case OMA_CODECID_LPCM:
363 /* PCM 44.1 kHz 16 bit stereo big-endian */
364 st->codec->channels = 2;
365 st->codec->sample_rate = 44100;
367 /* bit rate = sample rate x PCM block align (= 4) x 8 */
368 st->codec->bit_rate = st->codec->sample_rate * 32;
369 st->codec->bits_per_coded_sample = av_get_bits_per_sample(st->codec->codec_id);
370 avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
373 av_log(s, AV_LOG_ERROR, "Unsupported codec %d!\n",buf[32]);
377 st->codec->block_align = framesize;
383 static int oma_read_packet(AVFormatContext *s, AVPacket *pkt)
385 OMAContext *oc = s->priv_data;
386 int packet_size = s->streams[0]->codec->block_align;
387 int ret = av_get_packet(s->pb, pkt, packet_size);
392 pkt->stream_index = 0;
395 /* previous unencrypted block saved in IV for the next packet (CBC mode) */
396 av_des_crypt(&oc->av_des, pkt->data, pkt->data, (packet_size >> 3), oc->iv, 1);
402 static int oma_read_probe(AVProbeData *p)
405 unsigned tag_len = 0;
409 if (p->buf_size < ID3v2_HEADER_SIZE ||
410 !ff_id3v2_match(buf, ID3v2_EA3_MAGIC) ||
411 buf[3] != 3 || // version must be 3
412 buf[4]) // flags byte zero
415 tag_len = ff_id3v2_tag_len(buf);
417 /* This check cannot overflow as tag_len has at most 28 bits */
418 if (p->buf_size < tag_len + 5)
419 /* EA3 header comes late, might be outside of the probe buffer */
420 return AVPROBE_SCORE_MAX / 2;
424 if (!memcmp(buf, "EA3", 3) && !buf[4] && buf[5] == EA3_HEADER_SIZE)
425 return AVPROBE_SCORE_MAX;
430 static int oma_read_seek(struct AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
432 OMAContext *oc = s->priv_data;
434 pcm_read_seek(s, stream_index, timestamp, flags);
437 /* readjust IV for CBC */
438 int64_t pos = avio_tell(s->pb);
439 if (pos < oc->content_start)
440 memset(oc->iv, 0, 8);
442 if (avio_seek(s->pb, -8, SEEK_CUR) < 0 || avio_read(s->pb, oc->iv, 8) < 8) {
443 memset(oc->iv, 0, 8);
452 AVInputFormat ff_oma_demuxer = {
454 .long_name = NULL_IF_CONFIG_SMALL("Sony OpenMG audio"),
455 .priv_data_size = sizeof(OMAContext),
456 .read_probe = oma_read_probe,
457 .read_header = oma_read_header,
458 .read_packet = oma_read_packet,
459 .read_seek = oma_read_seek,
460 .flags = AVFMT_GENERIC_INDEX,
461 .extensions = "oma,omg,aa3",
462 .codec_tag = (const AVCodecTag* const []){codec_oma_tags, 0},