2 * Sony OpenMG (OMA) demuxer
4 * Copyright (c) 2008 Maxim Poliakovski
5 * 2008 Benjamin Larsson
8 * This file is part of FFmpeg.
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.
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.
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
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!
44 #include "libavutil/intreadwrite.h"
45 #include "libavutil/des.h"
50 #define EA3_HEADER_SIZE 96
51 #define ID3v2_EA3_MAGIC "ea3"
52 #define OMA_ENC_HEADER_SIZE 16
55 OMA_CODECID_ATRAC3 = 0,
56 OMA_CODECID_ATRAC3P = 1,
62 static const AVCodecTag codec_oma_tags[] = {
63 { CODEC_ID_ATRAC3, OMA_CODECID_ATRAC3 },
64 { CODEC_ID_ATRAC3P, OMA_CODECID_ATRAC3P },
65 { CODEC_ID_MP3, OMA_CODECID_MP3 },
68 static const uint64_t leaf_table[] = {
69 0xd79e8283acea4620, 0x7a9762f445afd0d8,
70 0x354d60a60b8c79f1, 0x584e1cde00b07aee,
71 0x1573cd93da7df623, 0x47f98d79620dd535
74 typedef struct OMAContext {
75 uint64_t content_start;
92 static void hex_log(AVFormatContext *s, int level, const char *name, const uint8_t *value, int len)
96 if (av_log_get_level() < level)
98 ff_data_to_hex(buf, value, len, 1);
100 av_log(s, level, "%s: %s\n", name, buf);
103 static int kset(AVFormatContext *s, const uint8_t *r_val, const uint8_t *n_val, int len)
105 OMAContext *oc = s->priv_data;
107 if (!r_val && !n_val)
110 len = FFMIN(len, 16);
112 /* use first 64 bits in the third round again */
114 if (r_val != oc->r_val) {
115 memset(oc->r_val, 0, 24);
116 memcpy(oc->r_val, r_val, len);
118 memcpy(&oc->r_val[16], r_val, 8);
121 if (n_val != oc->n_val) {
122 memset(oc->n_val, 0, 24);
123 memcpy(oc->n_val, n_val, len);
125 memcpy(&oc->n_val[16], n_val, 8);
131 static int rprobe(AVFormatContext *s, uint8_t *enc_header, const uint8_t *r_val)
133 OMAContext *oc = s->priv_data;
137 if (!enc_header || !r_val)
141 av_des_init(&av_des, r_val, 192, 1);
142 av_des_crypt(&av_des, oc->m_val, &enc_header[48], 1, NULL, 1);
145 av_des_init(&av_des, oc->m_val, 64, 0);
146 av_des_crypt(&av_des, oc->s_val, NULL, 1, NULL, 0);
149 pos = OMA_ENC_HEADER_SIZE + oc->k_size + oc->e_size;
150 av_des_init(&av_des, oc->s_val, 64, 0);
151 av_des_mac(&av_des, oc->sm_val, &enc_header[pos], (oc->i_size >> 3));
155 return memcmp(&enc_header[pos], oc->sm_val, 8) ? -1 : 0;
158 static int nprobe(AVFormatContext *s, uint8_t *enc_header, const uint8_t *n_val)
160 OMAContext *oc = s->priv_data;
161 uint32_t pos, taglen, datalen;
164 if (!enc_header || !n_val)
167 pos = OMA_ENC_HEADER_SIZE + oc->k_size;
168 if (!memcmp(&enc_header[pos], "EKB ", 4))
171 if (AV_RB32(&enc_header[pos]) != oc->rid)
172 av_log(s, AV_LOG_DEBUG, "Mismatching RID\n");
174 taglen = AV_RB32(&enc_header[pos+32]);
175 datalen = AV_RB32(&enc_header[pos+36]) >> 4;
179 av_des_init(&av_des, n_val, 192, 1);
180 while (datalen-- > 0) {
181 av_des_crypt(&av_des, oc->r_val, &enc_header[pos], 2, NULL, 1);
182 kset(s, oc->r_val, NULL, 16);
183 if (!rprobe(s, enc_header, oc->r_val))
191 static int decrypt_init(AVFormatContext *s, ID3v2ExtraMeta *em, uint8_t *header)
193 OMAContext *oc = s->priv_data;
194 ID3v2ExtraMetaGEOB *geob = NULL;
198 av_log(s, AV_LOG_INFO, "File is encrypted\n");
200 /* find GEOB metadata */
202 if (!strcmp(em->tag, "GEOB") &&
204 !strcmp(geob->description, "OMG_LSI") ||
205 !strcmp(geob->description, "OMG_BKLSI")) {
211 av_log(s, AV_LOG_ERROR, "No encryption header found\n");
215 if (geob->datasize < 64) {
216 av_log(s, AV_LOG_ERROR, "Invalid GEOB data size: %u\n", geob->datasize);
222 if (AV_RB16(gdata) != 1)
223 av_log(s, AV_LOG_WARNING, "Unknown version in encryption header\n");
225 oc->k_size = AV_RB16(&gdata[2]);
226 oc->e_size = AV_RB16(&gdata[4]);
227 oc->i_size = AV_RB16(&gdata[6]);
228 oc->s_size = AV_RB16(&gdata[8]);
230 if (memcmp(&gdata[OMA_ENC_HEADER_SIZE], "KEYRING ", 12)) {
231 av_log(s, AV_LOG_ERROR, "Invalid encryption header\n");
234 oc->rid = AV_RB32(&gdata[OMA_ENC_HEADER_SIZE + 28]);
235 av_log(s, AV_LOG_DEBUG, "RID: %.8x\n", oc->rid);
237 memcpy(oc->iv, &header[0x58], 8);
238 hex_log(s, AV_LOG_DEBUG, "IV", oc->iv, 8);
240 hex_log(s, AV_LOG_DEBUG, "CBC-MAC", &gdata[OMA_ENC_HEADER_SIZE+oc->k_size+oc->e_size+oc->i_size], 8);
243 kset(s, s->key, s->key, s->keylen);
245 if (!memcmp(oc->r_val, (const uint8_t[8]){0}, 8) ||
246 rprobe(s, gdata, oc->r_val) < 0 &&
247 nprobe(s, gdata, oc->n_val) < 0) {
249 for (i = 0; i < sizeof(leaf_table); i += 2) {
251 AV_WL64(buf, leaf_table[i]);
252 AV_WL64(&buf[8], leaf_table[i+1]);
253 kset(s, buf, buf, 16);
254 if (!rprobe(s, gdata, oc->r_val) || !nprobe(s, gdata, oc->n_val))
257 if (i >= sizeof(leaf_table)) {
258 av_log(s, AV_LOG_ERROR, "Invalid key\n");
264 av_des_init(&oc->av_des, oc->m_val, 64, 0);
265 av_des_crypt(&oc->av_des, oc->e_val, &gdata[OMA_ENC_HEADER_SIZE + 40], 1, NULL, 0);
266 hex_log(s, AV_LOG_DEBUG, "EK", oc->e_val, 8);
269 av_des_init(&oc->av_des, oc->e_val, 64, 1);
274 static int oma_read_header(AVFormatContext *s,
275 AVFormatParameters *ap)
277 static const uint16_t srate_tab[6] = {320,441,480,882,960,0};
278 int ret, framesize, jsflag, samplerate;
279 uint32_t codec_params;
281 uint8_t buf[EA3_HEADER_SIZE];
284 ID3v2ExtraMeta *extra_meta = NULL;
285 OMAContext *oc = s->priv_data;
287 ff_id3v2_read_all(s, ID3v2_EA3_MAGIC, &extra_meta);
288 ret = avio_read(s->pb, buf, EA3_HEADER_SIZE);
289 if (ret < EA3_HEADER_SIZE)
292 if (memcmp(buf, ((const uint8_t[]){'E', 'A', '3'}),3) || buf[4] != 0 || buf[5] != EA3_HEADER_SIZE) {
293 av_log(s, AV_LOG_ERROR, "Couldn't find the EA3 header !\n");
297 oc->content_start = avio_tell(s->pb);
300 eid = AV_RB16(&buf[6]);
301 if (eid != -1 && eid != -128 && decrypt_init(s, extra_meta, buf) < 0) {
302 ff_id3v2_free_extra_meta(&extra_meta);
306 ff_id3v2_free_extra_meta(&extra_meta);
308 codec_params = AV_RB24(&buf[33]);
310 st = av_new_stream(s, 0);
312 return AVERROR(ENOMEM);
315 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
316 st->codec->codec_tag = buf[32];
317 st->codec->codec_id = ff_codec_get_id(codec_oma_tags, st->codec->codec_tag);
320 case OMA_CODECID_ATRAC3:
321 samplerate = srate_tab[(codec_params >> 13) & 7]*100;
322 if (samplerate != 44100)
323 av_log_ask_for_sample(s, "Unsupported sample rate: %d\n",
326 framesize = (codec_params & 0x3FF) * 8;
327 jsflag = (codec_params >> 17) & 1; /* get stereo coding mode, 1 for joint-stereo */
328 st->codec->channels = 2;
329 st->codec->sample_rate = samplerate;
330 st->codec->bit_rate = st->codec->sample_rate * framesize * 8 / 1024;
332 /* fake the atrac3 extradata (wav format, makes stream copy to wav work) */
333 st->codec->extradata_size = 14;
334 edata = av_mallocz(14 + FF_INPUT_BUFFER_PADDING_SIZE);
336 return AVERROR(ENOMEM);
338 st->codec->extradata = edata;
339 AV_WL16(&edata[0], 1); // always 1
340 AV_WL32(&edata[2], samplerate); // samples rate
341 AV_WL16(&edata[6], jsflag); // coding mode
342 AV_WL16(&edata[8], jsflag); // coding mode
343 AV_WL16(&edata[10], 1); // always 1
344 // AV_WL16(&edata[12], 0); // always 0
346 av_set_pts_info(st, 64, 1, st->codec->sample_rate);
348 case OMA_CODECID_ATRAC3P:
349 st->codec->channels = (codec_params >> 10) & 7;
350 framesize = ((codec_params & 0x3FF) * 8) + 8;
351 st->codec->sample_rate = srate_tab[(codec_params >> 13) & 7]*100;
352 st->codec->bit_rate = st->codec->sample_rate * framesize * 8 / 1024;
353 av_set_pts_info(st, 64, 1, st->codec->sample_rate);
354 av_log(s, AV_LOG_ERROR, "Unsupported codec ATRAC3+!\n");
356 case OMA_CODECID_MP3:
357 st->need_parsing = AVSTREAM_PARSE_FULL;
361 av_log(s, AV_LOG_ERROR, "Unsupported codec %d!\n",buf[32]);
365 st->codec->block_align = framesize;
371 static int oma_read_packet(AVFormatContext *s, AVPacket *pkt)
373 OMAContext *oc = s->priv_data;
374 int packet_size = s->streams[0]->codec->block_align;
375 int ret = av_get_packet(s->pb, pkt, packet_size);
380 pkt->stream_index = 0;
383 /* previous unencrypted block saved in IV for the next packet (CBC mode) */
384 av_des_crypt(&oc->av_des, pkt->data, pkt->data, (packet_size >> 3), oc->iv, 1);
390 static int oma_read_probe(AVProbeData *p)
393 unsigned tag_len = 0;
396 /* version must be 3 and flags byte zero */
397 if (ff_id3v2_match(buf, ID3v2_EA3_MAGIC) && buf[3] == 3 && !buf[4])
398 tag_len = ff_id3v2_tag_len(buf);
400 // This check cannot overflow as tag_len has at most 28 bits
401 if (p->buf_size < tag_len + 5)
406 if (!memcmp(buf, "EA3", 3) && !buf[4] && buf[5] == EA3_HEADER_SIZE)
407 return AVPROBE_SCORE_MAX;
412 static int oma_read_seek(struct AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
414 OMAContext *oc = s->priv_data;
416 pcm_read_seek(s, stream_index, timestamp, flags);
419 /* readjust IV for CBC */
420 int64_t pos = avio_tell(s->pb);
421 if (pos < oc->content_start)
422 memset(oc->iv, 0, 8);
424 if (avio_seek(s->pb, -8, SEEK_CUR) < 0 || avio_read(s->pb, oc->iv, 8) < 8) {
425 memset(oc->iv, 0, 8);
434 AVInputFormat ff_oma_demuxer = {
436 .long_name = NULL_IF_CONFIG_SMALL("Sony OpenMG audio"),
437 .priv_data_size = sizeof(OMAContext),
438 .read_probe = oma_read_probe,
439 .read_header = oma_read_header,
440 .read_packet = oma_read_packet,
441 .read_seek = oma_read_seek,
442 .flags = AVFMT_GENERIC_INDEX,
443 .extensions = "oma,omg,aa3",
444 .codec_tag = (const AVCodecTag* const []){codec_oma_tags, 0},