1 /*
2 * Sony OpenMG (OMA) demuxer
3 *
4 * Copyright (c) 2008, 2013 Maxim Poliakovski
5 * 2008 Benjamin Larsson
6 * 2011 David Goldwich
7 *
8 * This file is part of FFmpeg.
9 *
10 * FFmpeg 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.
14 *
15 * FFmpeg 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.
19 *
20 * You should have received a copy of the GNU Lesser General Public
21 * License along with FFmpeg; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 */
24
25 /**
26 * @file
27 * This is a demuxer for Sony OpenMG Music files
28 *
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!).
39 *
40 * Supported decoders: ATRAC3, ATRAC3+, MP3, LPCM
41 */
42
43 #include <inttypes.h>
44
45 #include "libavutil/channel_layout.h"
46 #include "avformat.h"
47 #include "internal.h"
48 #include "libavutil/intreadwrite.h"
49 #include "libavutil/des.h"
50 #include "libavutil/mathematics.h"
51 #include "oma.h"
52 #include "pcm.h"
53 #include "id3v2.h"
54
55
56 static const uint64_t leaf_table[] = {
57 0xd79e8283acea4620, 0x7a9762f445afd0d8,
58 0x354d60a60b8c79f1, 0x584e1cde00b07aee,
59 0x1573cd93da7df623, 0x47f98d79620dd535
60 };
61
62 /** map ATRAC-X channel id to internal channel layout */
63 static const uint64_t oma_chid_to_native_layout[7] = {
64 AV_CH_LAYOUT_MONO,
65 AV_CH_LAYOUT_STEREO,
66 AV_CH_LAYOUT_SURROUND,
67 AV_CH_LAYOUT_4POINT0,
68 AV_CH_LAYOUT_5POINT1_BACK,
69 AV_CH_LAYOUT_6POINT1_BACK,
70 AV_CH_LAYOUT_7POINT1
71 };
72
73 /** map ATRAC-X channel id to total number of channels */
74 static const int oma_chid_to_num_channels[7] = { 1, 2, 3, 4, 6, 7, 8 };
75
76 typedef struct OMAContext {
77 uint64_t content_start;
78 int encrypted;
79 uint16_t k_size;
80 uint16_t e_size;
81 uint16_t i_size;
82 uint16_t s_size;
83 uint32_t rid;
84 uint8_t r_val[24];
85 uint8_t n_val[24];
86 uint8_t m_val[8];
87 uint8_t s_val[8];
88 uint8_t sm_val[8];
89 uint8_t e_val[8];
90 uint8_t iv[8];
91 struct AVDES *av_des;
92
93 int (*read_packet)(AVFormatContext *s, AVPacket *pkt);
94 } OMAContext;
95
oma_read_close(AVFormatContext * s)96 static int oma_read_close(AVFormatContext *s)
97 {
98 OMAContext *oc = s->priv_data;
99 av_freep(&oc->av_des);
100 return 0;
101 }
102
hex_log(AVFormatContext * s,int level,const char * name,const uint8_t * value,int len)103 static void hex_log(AVFormatContext *s, int level,
104 const char *name, const uint8_t *value, int len)
105 {
106 char buf[33];
107 len = FFMIN(len, 16);
108 if (av_log_get_level() < level)
109 return;
110 ff_data_to_hex(buf, value, len, 1);
111 buf[len << 1] = '\0';
112 av_log(s, level, "%s: %s\n", name, buf);
113 }
114
kset(AVFormatContext * s,const uint8_t * r_val,const uint8_t * n_val,int len)115 static int kset(AVFormatContext *s, const uint8_t *r_val, const uint8_t *n_val,
116 int len)
117 {
118 OMAContext *oc = s->priv_data;
119
120 if (!r_val && !n_val)
121 return -1;
122
123 len = FFMIN(len, 16);
124
125 /* use first 64 bits in the third round again */
126 if (r_val) {
127 if (r_val != oc->r_val) {
128 memset(oc->r_val, 0, 24);
129 memcpy(oc->r_val, r_val, len);
130 }
131 memcpy(&oc->r_val[16], r_val, 8);
132 }
133 if (n_val) {
134 if (n_val != oc->n_val) {
135 memset(oc->n_val, 0, 24);
136 memcpy(oc->n_val, n_val, len);
137 }
138 memcpy(&oc->n_val[16], n_val, 8);
139 }
140
141 return 0;
142 }
143
144 #define OMA_RPROBE_M_VAL 48 + 1
145
rprobe(AVFormatContext * s,uint8_t * enc_header,unsigned size,const uint8_t * r_val)146 static int rprobe(AVFormatContext *s, uint8_t *enc_header, unsigned size,
147 const uint8_t *r_val)
148 {
149 OMAContext *oc = s->priv_data;
150 unsigned int pos;
151 struct AVDES *av_des;
152
153 if (!enc_header || !r_val ||
154 size < OMA_ENC_HEADER_SIZE + oc->k_size + oc->e_size + oc->i_size ||
155 size < OMA_RPROBE_M_VAL)
156 return -1;
157
158 av_des = av_des_alloc();
159 if (!av_des)
160 return AVERROR(ENOMEM);
161
162 /* m_val */
163 av_des_init(av_des, r_val, 192, 1);
164 av_des_crypt(av_des, oc->m_val, &enc_header[48], 1, NULL, 1);
165
166 /* s_val */
167 av_des_init(av_des, oc->m_val, 64, 0);
168 av_des_crypt(av_des, oc->s_val, NULL, 1, NULL, 0);
169
170 /* sm_val */
171 pos = OMA_ENC_HEADER_SIZE + oc->k_size + oc->e_size;
172 av_des_init(av_des, oc->s_val, 64, 0);
173 av_des_mac(av_des, oc->sm_val, &enc_header[pos], (oc->i_size >> 3));
174
175 pos += oc->i_size;
176
177 av_free(av_des);
178
179 return memcmp(&enc_header[pos], oc->sm_val, 8) ? -1 : 0;
180 }
181
nprobe(AVFormatContext * s,uint8_t * enc_header,unsigned size,const uint8_t * n_val)182 static int nprobe(AVFormatContext *s, uint8_t *enc_header, unsigned size,
183 const uint8_t *n_val)
184 {
185 OMAContext *oc = s->priv_data;
186 uint64_t pos;
187 uint32_t taglen, datalen;
188 struct AVDES *av_des;
189
190 if (!enc_header || !n_val ||
191 size < OMA_ENC_HEADER_SIZE + oc->k_size + 4)
192 return -1;
193
194 pos = OMA_ENC_HEADER_SIZE + oc->k_size;
195 if (!memcmp(&enc_header[pos], "EKB ", 4))
196 pos += 32;
197
198 if (size < pos + 44)
199 return -1;
200
201 if (AV_RB32(&enc_header[pos]) != oc->rid)
202 av_log(s, AV_LOG_DEBUG, "Mismatching RID\n");
203
204 taglen = AV_RB32(&enc_header[pos + 32]);
205 datalen = AV_RB32(&enc_header[pos + 36]) >> 4;
206
207 pos += 44LL + taglen;
208
209 if (pos + (((uint64_t)datalen) << 4) > size)
210 return -1;
211
212 av_des = av_des_alloc();
213 if (!av_des)
214 return AVERROR(ENOMEM);
215
216 av_des_init(av_des, n_val, 192, 1);
217 while (datalen-- > 0) {
218 av_des_crypt(av_des, oc->r_val, &enc_header[pos], 2, NULL, 1);
219 kset(s, oc->r_val, NULL, 16);
220 if (!rprobe(s, enc_header, size, oc->r_val)) {
221 av_free(av_des);
222 return 0;
223 }
224 pos += 16;
225 }
226
227 av_free(av_des);
228 return -1;
229 }
230
decrypt_init(AVFormatContext * s,ID3v2ExtraMeta * em,uint8_t * header)231 static int decrypt_init(AVFormatContext *s, ID3v2ExtraMeta *em, uint8_t *header)
232 {
233 OMAContext *oc = s->priv_data;
234 ID3v2ExtraMetaGEOB *geob = NULL;
235 uint8_t *gdata;
236
237 oc->encrypted = 1;
238 av_log(s, AV_LOG_INFO, "File is encrypted\n");
239
240 /* find GEOB metadata */
241 for (; em; em = em->next) {
242 if (strcmp(em->tag, "GEOB"))
243 continue;
244 geob = &em->data.geob;
245 if (!strcmp(geob->description, "OMG_LSI") ||
246 !strcmp(geob->description, "OMG_BKLSI"))
247 break;
248 }
249 if (!em) {
250 av_log(s, AV_LOG_ERROR, "No encryption header found\n");
251 return AVERROR_INVALIDDATA;
252 }
253
254 if (geob->datasize < 64) {
255 av_log(s, AV_LOG_ERROR,
256 "Invalid GEOB data size: %"PRIu32"\n", geob->datasize);
257 return AVERROR_INVALIDDATA;
258 }
259
260 gdata = geob->data;
261
262 if (AV_RB16(gdata) != 1)
263 av_log(s, AV_LOG_WARNING, "Unknown version in encryption header\n");
264
265 oc->k_size = AV_RB16(&gdata[2]);
266 oc->e_size = AV_RB16(&gdata[4]);
267 oc->i_size = AV_RB16(&gdata[6]);
268 oc->s_size = AV_RB16(&gdata[8]);
269
270 if (memcmp(&gdata[OMA_ENC_HEADER_SIZE], "KEYRING ", 12)) {
271 av_log(s, AV_LOG_ERROR, "Invalid encryption header\n");
272 return AVERROR_INVALIDDATA;
273 }
274 if (OMA_ENC_HEADER_SIZE + oc->k_size + oc->e_size + oc->i_size + 8 > geob->datasize ||
275 OMA_ENC_HEADER_SIZE + 48 > geob->datasize) {
276 av_log(s, AV_LOG_ERROR, "Too little GEOB data\n");
277 return AVERROR_INVALIDDATA;
278 }
279 oc->rid = AV_RB32(&gdata[OMA_ENC_HEADER_SIZE + 28]);
280 av_log(s, AV_LOG_DEBUG, "RID: %.8"PRIx32"\n", oc->rid);
281
282 memcpy(oc->iv, &header[0x58], 8);
283 hex_log(s, AV_LOG_DEBUG, "IV", oc->iv, 8);
284
285 hex_log(s, AV_LOG_DEBUG, "CBC-MAC",
286 &gdata[OMA_ENC_HEADER_SIZE + oc->k_size + oc->e_size + oc->i_size],
287 8);
288
289 if (s->keylen > 0) {
290 kset(s, s->key, s->key, s->keylen);
291 }
292 if (!memcmp(oc->r_val, (const uint8_t[8]){0}, 8) ||
293 rprobe(s, gdata, geob->datasize, oc->r_val) < 0 &&
294 nprobe(s, gdata, geob->datasize, oc->n_val) < 0) {
295 int i;
296 for (i = 0; i < FF_ARRAY_ELEMS(leaf_table); i += 2) {
297 uint8_t buf[16];
298 AV_WL64(buf, leaf_table[i]);
299 AV_WL64(&buf[8], leaf_table[i + 1]);
300 kset(s, buf, buf, 16);
301 if (!rprobe(s, gdata, geob->datasize, oc->r_val) ||
302 !nprobe(s, gdata, geob->datasize, oc->n_val))
303 break;
304 }
305 if (i >= FF_ARRAY_ELEMS(leaf_table)) {
306 av_log(s, AV_LOG_ERROR, "Invalid key\n");
307 return AVERROR_INVALIDDATA;
308 }
309 }
310
311 oc->av_des = av_des_alloc();
312 if (!oc->av_des)
313 return AVERROR(ENOMEM);
314
315 /* e_val */
316 av_des_init(oc->av_des, oc->m_val, 64, 0);
317 av_des_crypt(oc->av_des, oc->e_val,
318 &gdata[OMA_ENC_HEADER_SIZE + 40], 1, NULL, 0);
319 hex_log(s, AV_LOG_DEBUG, "EK", oc->e_val, 8);
320
321 /* init e_val */
322 av_des_init(oc->av_des, oc->e_val, 64, 1);
323
324 return 0;
325 }
326
read_packet(AVFormatContext * s,AVPacket * pkt)327 static int read_packet(AVFormatContext *s, AVPacket *pkt)
328 {
329 OMAContext *oc = s->priv_data;
330 AVStream *st = s->streams[0];
331 int packet_size = st->codecpar->block_align;
332 int byte_rate = st->codecpar->bit_rate >> 3;
333 int64_t pos = avio_tell(s->pb);
334 int ret = av_get_packet(s->pb, pkt, packet_size);
335
336 if (ret < packet_size)
337 pkt->flags |= AV_PKT_FLAG_CORRUPT;
338
339 if (ret < 0)
340 return ret;
341 if (!ret)
342 return AVERROR_EOF;
343
344 pkt->stream_index = 0;
345
346 if (pos >= oc->content_start && byte_rate > 0) {
347 pkt->pts =
348 pkt->dts = av_rescale(pos - oc->content_start, st->time_base.den,
349 byte_rate * (int64_t)st->time_base.num);
350 }
351
352 if (oc->encrypted) {
353 /* previous unencrypted block saved in IV for
354 * the next packet (CBC mode) */
355 if (ret == packet_size)
356 av_des_crypt(oc->av_des, pkt->data, pkt->data,
357 (packet_size >> 3), oc->iv, 1);
358 else
359 memset(oc->iv, 0, 8);
360 }
361
362 return ret;
363 }
364
aal_read_packet(AVFormatContext * s,AVPacket * pkt)365 static int aal_read_packet(AVFormatContext *s, AVPacket *pkt)
366 {
367 int64_t pos = avio_tell(s->pb);
368 int ret, pts;
369 int packet_size;
370 unsigned tag;
371
372 if (avio_feof(s->pb))
373 return AVERROR_EOF;
374
375 tag = avio_rb24(s->pb);
376 if (tag == 0)
377 return AVERROR_EOF;
378 else if (tag != MKBETAG(0,'B','L','K'))
379 return AVERROR_INVALIDDATA;
380
381 avio_skip(s->pb, 1);
382 packet_size = avio_rb16(s->pb);
383 avio_skip(s->pb, 2);
384 pts = avio_rb32(s->pb);
385 avio_skip(s->pb, 12);
386 ret = av_get_packet(s->pb, pkt, packet_size);
387 if (ret < packet_size)
388 pkt->flags |= AV_PKT_FLAG_CORRUPT;
389
390 if (ret < 0)
391 return ret;
392 if (!ret)
393 return AVERROR_EOF;
394
395 pkt->stream_index = 0;
396 pkt->pos = pos;
397 if (s->streams[0]->codecpar->codec_id == AV_CODEC_ID_ATRAC3AL) {
398 pkt->duration = 1024;
399 pkt->pts = pts * 1024LL;
400 } else {
401 pkt->duration = 2048;
402 pkt->pts = pts * 2048LL;
403 }
404
405 return ret;
406 }
407
oma_read_header(AVFormatContext * s)408 static int oma_read_header(AVFormatContext *s)
409 {
410 int ret, framesize, jsflag, samplerate;
411 uint32_t codec_params, channel_id;
412 int16_t eid;
413 uint8_t buf[EA3_HEADER_SIZE];
414 uint8_t *edata;
415 AVStream *st;
416 ID3v2ExtraMeta *extra_meta = NULL;
417 OMAContext *oc = s->priv_data;
418
419 ff_id3v2_read(s, ID3v2_EA3_MAGIC, &extra_meta, 0);
420 if ((ret = ff_id3v2_parse_chapters(s, extra_meta)) < 0) {
421 ff_id3v2_free_extra_meta(&extra_meta);
422 return ret;
423 }
424
425 ret = avio_read(s->pb, buf, EA3_HEADER_SIZE);
426 if (ret < EA3_HEADER_SIZE) {
427 ff_id3v2_free_extra_meta(&extra_meta);
428 return -1;
429 }
430
431 if (memcmp(buf, ((const uint8_t[]){'E', 'A', '3'}), 3) ||
432 buf[4] != 0 || buf[5] != EA3_HEADER_SIZE) {
433 ff_id3v2_free_extra_meta(&extra_meta);
434 av_log(s, AV_LOG_ERROR, "Couldn't find the EA3 header !\n");
435 return AVERROR_INVALIDDATA;
436 }
437
438 oc->content_start = avio_tell(s->pb);
439
440 /* encrypted file */
441 eid = AV_RB16(&buf[6]);
442 if (eid != -1 && eid != -128 && decrypt_init(s, extra_meta, buf) < 0) {
443 ff_id3v2_free_extra_meta(&extra_meta);
444 return -1;
445 }
446
447 ff_id3v2_free_extra_meta(&extra_meta);
448
449 codec_params = AV_RB24(&buf[33]);
450
451 st = avformat_new_stream(s, NULL);
452 if (!st) {
453 ret = AVERROR(ENOMEM);
454 goto fail;
455 }
456
457 st->start_time = 0;
458 st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
459 st->codecpar->codec_tag = buf[32];
460 st->codecpar->codec_id = ff_codec_get_id(ff_oma_codec_tags,
461 st->codecpar->codec_tag);
462
463 oc->read_packet = read_packet;
464
465 switch (buf[32]) {
466 case OMA_CODECID_ATRAC3:
467 samplerate = ff_oma_srate_tab[(codec_params >> 13) & 7] * 100;
468 if (!samplerate) {
469 av_log(s, AV_LOG_ERROR, "Unsupported sample rate\n");
470 ret = AVERROR_INVALIDDATA;
471 goto fail;
472 }
473 if (samplerate != 44100)
474 avpriv_request_sample(s, "Sample rate %d", samplerate);
475
476 framesize = (codec_params & 0x3FF) * 8;
477
478 /* get stereo coding mode, 1 for joint-stereo */
479 jsflag = (codec_params >> 17) & 1;
480
481 st->codecpar->channels = 2;
482 st->codecpar->channel_layout = AV_CH_LAYOUT_STEREO;
483 st->codecpar->sample_rate = samplerate;
484 st->codecpar->bit_rate = st->codecpar->sample_rate * framesize / (1024 / 8);
485
486 /* fake the ATRAC3 extradata
487 * (wav format, makes stream copy to wav work) */
488 if ((ret = ff_alloc_extradata(st->codecpar, 14)) < 0)
489 goto fail;
490
491 edata = st->codecpar->extradata;
492 AV_WL16(&edata[0], 1); // always 1
493 AV_WL32(&edata[2], samplerate); // samples rate
494 AV_WL16(&edata[6], jsflag); // coding mode
495 AV_WL16(&edata[8], jsflag); // coding mode
496 AV_WL16(&edata[10], 1); // always 1
497 // AV_WL16(&edata[12], 0); // always 0
498
499 avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
500 break;
501 case OMA_CODECID_ATRAC3P:
502 channel_id = (codec_params >> 10) & 7;
503 if (!channel_id) {
504 av_log(s, AV_LOG_ERROR,
505 "Invalid ATRAC-X channel id: %"PRIu32"\n", channel_id);
506 ret = AVERROR_INVALIDDATA;
507 goto fail;
508 }
509 st->codecpar->channel_layout = oma_chid_to_native_layout[channel_id - 1];
510 st->codecpar->channels = oma_chid_to_num_channels[channel_id - 1];
511 framesize = ((codec_params & 0x3FF) * 8) + 8;
512 samplerate = ff_oma_srate_tab[(codec_params >> 13) & 7] * 100;
513 if (!samplerate) {
514 av_log(s, AV_LOG_ERROR, "Unsupported sample rate\n");
515 ret = AVERROR_INVALIDDATA;
516 goto fail;
517 }
518 st->codecpar->sample_rate = samplerate;
519 st->codecpar->bit_rate = samplerate * framesize / (2048 / 8);
520 avpriv_set_pts_info(st, 64, 1, samplerate);
521 break;
522 case OMA_CODECID_MP3:
523 st->need_parsing = AVSTREAM_PARSE_FULL_RAW;
524 framesize = 1024;
525 break;
526 case OMA_CODECID_LPCM:
527 /* PCM 44.1 kHz 16 bit stereo big-endian */
528 st->codecpar->channels = 2;
529 st->codecpar->channel_layout = AV_CH_LAYOUT_STEREO;
530 st->codecpar->sample_rate = 44100;
531 framesize = 1024;
532 /* bit rate = sample rate x PCM block align (= 4) x 8 */
533 st->codecpar->bit_rate = st->codecpar->sample_rate * 32;
534 st->codecpar->bits_per_coded_sample =
535 av_get_bits_per_sample(st->codecpar->codec_id);
536 avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
537 break;
538 case OMA_CODECID_ATRAC3AL:
539 st->codecpar->channels = 2;
540 st->codecpar->channel_layout = AV_CH_LAYOUT_STEREO;
541 st->codecpar->sample_rate = 44100;
542 avpriv_set_pts_info(st, 64, 1, 44100);
543 oc->read_packet = aal_read_packet;
544 framesize = 4096;
545 break;
546 case OMA_CODECID_ATRAC3PAL:
547 st->codecpar->channel_layout = AV_CH_LAYOUT_STEREO;
548 st->codecpar->channels = 2;
549 st->codecpar->sample_rate = 44100;
550 avpriv_set_pts_info(st, 64, 1, 44100);
551 oc->read_packet = aal_read_packet;
552 framesize = 4096;
553 break;
554 default:
555 av_log(s, AV_LOG_ERROR, "Unsupported codec %d!\n", buf[32]);
556 ret = AVERROR(ENOSYS);
557 goto fail;
558 }
559
560 st->codecpar->block_align = framesize;
561
562 return 0;
563 fail:
564 oma_read_close(s);
565 return ret;
566 }
567
oma_read_packet(AVFormatContext * s,AVPacket * pkt)568 static int oma_read_packet(AVFormatContext *s, AVPacket *pkt)
569 {
570 OMAContext *oc = s->priv_data;
571 return oc->read_packet(s, pkt);
572 }
573
oma_read_probe(const AVProbeData * p)574 static int oma_read_probe(const AVProbeData *p)
575 {
576 const uint8_t *buf = p->buf;
577 unsigned tag_len = 0;
578
579 if (p->buf_size >= ID3v2_HEADER_SIZE && ff_id3v2_match(buf, ID3v2_EA3_MAGIC))
580 tag_len = ff_id3v2_tag_len(buf);
581
582 /* This check cannot overflow as tag_len has at most 28 bits */
583 if (p->buf_size < tag_len + 5)
584 /* EA3 header comes late, might be outside of the probe buffer */
585 return tag_len ? AVPROBE_SCORE_EXTENSION/2 : 0;
586
587 buf += tag_len;
588
589 if (!memcmp(buf, "EA3", 3) && !buf[4] && buf[5] == EA3_HEADER_SIZE)
590 return AVPROBE_SCORE_MAX;
591 else
592 return 0;
593 }
594
oma_read_seek(struct AVFormatContext * s,int stream_index,int64_t timestamp,int flags)595 static int oma_read_seek(struct AVFormatContext *s,
596 int stream_index, int64_t timestamp, int flags)
597 {
598 OMAContext *oc = s->priv_data;
599 AVStream *st = s->streams[0];
600 int64_t err;
601
602 if (st->codecpar->codec_id == AV_CODEC_ID_ATRAC3PAL ||
603 st->codecpar->codec_id == AV_CODEC_ID_ATRAC3AL)
604 return -1;
605
606 err = ff_pcm_read_seek(s, stream_index, timestamp, flags);
607 if (!oc->encrypted)
608 return err;
609
610 /* readjust IV for CBC */
611 if (err || avio_tell(s->pb) < oc->content_start)
612 goto wipe;
613 if ((err = avio_seek(s->pb, -8, SEEK_CUR)) < 0)
614 goto wipe;
615 if ((err = avio_read(s->pb, oc->iv, 8)) < 8) {
616 if (err >= 0)
617 err = AVERROR_EOF;
618 goto wipe;
619 }
620
621 return 0;
622 wipe:
623 memset(oc->iv, 0, 8);
624 return err;
625 }
626
627 AVInputFormat ff_oma_demuxer = {
628 .name = "oma",
629 .long_name = NULL_IF_CONFIG_SMALL("Sony OpenMG audio"),
630 .priv_data_size = sizeof(OMAContext),
631 .read_probe = oma_read_probe,
632 .read_header = oma_read_header,
633 .read_packet = oma_read_packet,
634 .read_seek = oma_read_seek,
635 .read_close = oma_read_close,
636 .flags = AVFMT_GENERIC_INDEX,
637 .extensions = "oma,omg,aa3",
638 .codec_tag = ff_oma_codec_tags_list,
639 };
640