libavformat/omadec.c

   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 Libav.
   9  *
  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.
  14  *
  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.
  19  *
  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
  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 "oma.h"
  51 #include "pcm.h"
  52 #include "id3v2.h"
  53
  54
  55 static const uint64_t leaf_table[] = {
  56     0xd79e8283acea4620, 0x7a9762f445afd0d8,
  57     0x354d60a60b8c79f1, 0x584e1cde00b07aee,
  58     0x1573cd93da7df623, 0x47f98d79620dd535
  59 };
  60
  61 typedef struct OMAContext {
  62     uint64_t content_start;
  63     int encrypted;
  64     uint16_t k_size;
  65     uint16_t e_size;
  66     uint16_t i_size;
  67     uint16_t s_size;
  68     uint32_t rid;
  69     uint8_t r_val[24];
  70     uint8_t n_val[24];
  71     uint8_t m_val[8];
  72     uint8_t s_val[8];
  73     uint8_t sm_val[8];
  74     uint8_t e_val[8];
  75     uint8_t iv[8];
  76     struct AVDES av_des;
  77 } OMAContext;
  78
  79 static void hex_log(AVFormatContext *s, int level,
  80                     const char *name, const uint8_t *value, int len)
  81 {
  82     char buf[33];
  83     len = FFMIN(len, 16);
  84     if (av_log_get_level() < level)
  85         return;
  86     ff_data_to_hex(buf, value, len, 1);
  87     buf[len << 1] = '\0';
  88     av_log(s, level, "%s: %s\n", name, buf);
  89 }
  90
  91 static int kset(AVFormatContext *s, const uint8_t *r_val, const uint8_t *n_val,
  92                 int len)
  93 {
  94     OMAContext *oc = s->priv_data;
  95
  96     if (!r_val && !n_val)
  97         return -1;
  98
  99     len = FFMIN(len, 16);
 100
 101     /* use first 64 bits in the third round again */
 102     if (r_val) {
 103         if (r_val != oc->r_val) {
 104             memset(oc->r_val, 0, 24);
 105             memcpy(oc->r_val, r_val, len);
 106         }
 107         memcpy(&oc->r_val[16], r_val, 8);
 108     }
 109     if (n_val) {
 110         if (n_val != oc->n_val) {
 111             memset(oc->n_val, 0, 24);
 112             memcpy(oc->n_val, n_val, len);
 113         }
 114         memcpy(&oc->n_val[16], n_val, 8);
 115     }
 116
 117     return 0;
 118 }
 119
 120 #define OMA_RPROBE_M_VAL 48 + 1
 121
 122 static int rprobe(AVFormatContext *s, uint8_t *enc_header, unsigned size,
 123                   const uint8_t *r_val)
 124 {
 125     OMAContext *oc = s->priv_data;
 126     unsigned int pos;
 127     struct AVDES av_des;
 128
 129     if (!enc_header || !r_val ||
 130         size < OMA_ENC_HEADER_SIZE + oc->k_size + oc->e_size + oc->i_size ||
 131         size < OMA_RPROBE_M_VAL)
 132         return -1;
 133
 134     /* m_val */
 135     av_des_init(&av_des, r_val, 192, 1);
 136     av_des_crypt(&av_des, oc->m_val, &enc_header[48], 1, NULL, 1);
 137
 138     /* s_val */
 139     av_des_init(&av_des, oc->m_val, 64, 0);
 140     av_des_crypt(&av_des, oc->s_val, NULL, 1, NULL, 0);
 141
 142     /* sm_val */
 143     pos = OMA_ENC_HEADER_SIZE + oc->k_size + oc->e_size;
 144     av_des_init(&av_des, oc->s_val, 64, 0);
 145     av_des_mac(&av_des, oc->sm_val, &enc_header[pos], (oc->i_size >> 3));
 146
 147     pos += oc->i_size;
 148
 149     return memcmp(&enc_header[pos], oc->sm_val, 8) ? -1 : 0;
 150 }
 151
 152 static int nprobe(AVFormatContext *s, uint8_t *enc_header, unsigned size,
 153                   const uint8_t *n_val)
 154 {
 155     OMAContext *oc = s->priv_data;
 156     uint64_t pos;
 157     uint32_t taglen, datalen;
 158     struct AVDES av_des;
 159
 160     if (!enc_header || !n_val ||
 161         size < OMA_ENC_HEADER_SIZE + oc->k_size + 4)
 162         return -1;
 163
 164     pos = OMA_ENC_HEADER_SIZE + oc->k_size;
 165     if (!memcmp(&enc_header[pos], "EKB ", 4))
 166         pos += 32;
 167
 168     if (size < pos + 44)
 169         return -1;
 170
 171     if (AV_RB32(&enc_header[pos]) != oc->rid)
 172         av_log(s, AV_LOG_DEBUG, "Mismatching RID\n");
 173
 174     taglen  = AV_RB32(&enc_header[pos + 32]);
 175     datalen = AV_RB32(&enc_header[pos + 36]) >> 4;
 176
 177     pos += 44;
 178     if (size - pos < taglen)
 179         return -1;
 180
 181     pos += taglen;
 182
 183     if (datalen << 4 > size - pos)
 184         return -1;
 185
 186     av_des_init(&av_des, n_val, 192, 1);
 187     while (datalen-- > 0) {
 188         av_des_crypt(&av_des, oc->r_val, &enc_header[pos], 2, NULL, 1);
 189         kset(s, oc->r_val, NULL, 16);
 190         if (!rprobe(s, enc_header, size, oc->r_val))
 191             return 0;
 192         pos += 16;
 193     }
 194
 195     return -1;
 196 }
 197
 198 static int decrypt_init(AVFormatContext *s, ID3v2ExtraMeta *em, uint8_t *header)
 199 {
 200     OMAContext *oc = s->priv_data;
 201     ID3v2ExtraMetaGEOB *geob = NULL;
 202     uint8_t *gdata;
 203
 204     oc->encrypted = 1;
 205     av_log(s, AV_LOG_INFO, "File is encrypted\n");
 206
 207     /* find GEOB metadata */
 208     while (em) {
 209         if (!strcmp(em->tag, "GEOB") &&
 210             (geob = em->data) &&
 211             (!strcmp(geob->description, "OMG_LSI") ||
 212              !strcmp(geob->description, "OMG_BKLSI"))) {
 213             break;
 214         }
 215         em = em->next;
 216     }
 217     if (!em) {
 218         av_log(s, AV_LOG_ERROR, "No encryption header found\n");
 219         return AVERROR_INVALIDDATA;
 220     }
 221
 222     if (geob->datasize < 64) {
 223         av_log(s, AV_LOG_ERROR,
 224                "Invalid GEOB data size: %"PRIu32"\n", geob->datasize);
 225         return AVERROR_INVALIDDATA;
 226     }
 227
 228     gdata = geob->data;
 229
 230     if (AV_RB16(gdata) != 1)
 231         av_log(s, AV_LOG_WARNING, "Unknown version in encryption header\n");
 232
 233     oc->k_size = AV_RB16(&gdata[2]);
 234     oc->e_size = AV_RB16(&gdata[4]);
 235     oc->i_size = AV_RB16(&gdata[6]);
 236     oc->s_size = AV_RB16(&gdata[8]);
 237
 238     if (memcmp(&gdata[OMA_ENC_HEADER_SIZE], "KEYRING     ", 12)) {
 239         av_log(s, AV_LOG_ERROR, "Invalid encryption header\n");
 240         return AVERROR_INVALIDDATA;
 241     }
 242     if (OMA_ENC_HEADER_SIZE + oc->k_size + oc->e_size + oc->i_size + 8 > geob->datasize ||
 243         OMA_ENC_HEADER_SIZE + 48 > geob->datasize) {
 244         av_log(s, AV_LOG_ERROR, "Too little GEOB data\n");
 245         return AVERROR_INVALIDDATA;
 246     }
 247     oc->rid = AV_RB32(&gdata[OMA_ENC_HEADER_SIZE + 28]);
 248     av_log(s, AV_LOG_DEBUG, "RID: %.8"PRIx32"\n", oc->rid);
 249
 250     memcpy(oc->iv, &header[0x58], 8);
 251     hex_log(s, AV_LOG_DEBUG, "IV", oc->iv, 8);
 252
 253     hex_log(s, AV_LOG_DEBUG, "CBC-MAC",
 254             &gdata[OMA_ENC_HEADER_SIZE + oc->k_size + oc->e_size + oc->i_size],
 255             8);
 256
 257     if (s->keylen > 0) {
 258         kset(s, s->key, s->key, s->keylen);
 259     }
 260     if (!memcmp(oc->r_val, (const uint8_t[8]){0}, 8) ||
 261         rprobe(s, gdata, geob->datasize, oc->r_val) < 0 &&
 262         nprobe(s, gdata, geob->datasize, oc->n_val) < 0) {
 263         int i;
 264         for (i = 0; i < FF_ARRAY_ELEMS(leaf_table); i += 2) {
 265             uint8_t buf[16];
 266             AV_WL64(buf,     leaf_table[i]);
 267             AV_WL64(&buf[8], leaf_table[i + 1]);
 268             kset(s, buf, buf, 16);
 269             if (!rprobe(s, gdata, geob->datasize, oc->r_val) ||
 270                 !nprobe(s, gdata, geob->datasize, oc->n_val))
 271                 break;
 272         }
 273         if (i >= FF_ARRAY_ELEMS(leaf_table)) {
 274             av_log(s, AV_LOG_ERROR, "Invalid key\n");
 275             return AVERROR_INVALIDDATA;
 276         }
 277     }
 278
 279     /* e_val */
 280     av_des_init(&oc->av_des, oc->m_val, 64, 0);
 281     av_des_crypt(&oc->av_des, oc->e_val,
 282                  &gdata[OMA_ENC_HEADER_SIZE + 40], 1, NULL, 0);
 283     hex_log(s, AV_LOG_DEBUG, "EK", oc->e_val, 8);
 284
 285     /* init e_val */
 286     av_des_init(&oc->av_des, oc->e_val, 64, 1);
 287
 288     return 0;
 289 }
 290
 291 static int oma_read_header(AVFormatContext *s)
 292 {
 293     int     ret, framesize, jsflag, samplerate;
 294     uint32_t codec_params, channel_id;
 295     int16_t eid;
 296     uint8_t buf[EA3_HEADER_SIZE];
 297     uint8_t *edata;
 298     AVStream *st;
 299     ID3v2ExtraMeta *extra_meta = NULL;
 300     OMAContext *oc = s->priv_data;
 301
 302     ff_id3v2_read(s, ID3v2_EA3_MAGIC, &extra_meta);
 303     ret = avio_read(s->pb, buf, EA3_HEADER_SIZE);
 304     if (ret < EA3_HEADER_SIZE)
 305         return -1;
 306
 307     if (memcmp(buf, ((const uint8_t[]){'E', 'A', '3'}), 3) ||
 308         buf[4] != 0 || buf[5] != EA3_HEADER_SIZE) {
 309         av_log(s, AV_LOG_ERROR, "Couldn't find the EA3 header !\n");
 310         return AVERROR_INVALIDDATA;
 311     }
 312
 313     oc->content_start = avio_tell(s->pb);
 314
 315     /* encrypted file */
 316     eid = AV_RB16(&buf[6]);
 317     if (eid != -1 && eid != -128 && decrypt_init(s, extra_meta, buf) < 0) {
 318         ff_id3v2_free_extra_meta(&extra_meta);
 319         return -1;
 320     }
 321
 322     ff_id3v2_free_extra_meta(&extra_meta);
 323
 324     codec_params = AV_RB24(&buf[33]);
 325
 326     st = avformat_new_stream(s, NULL);
 327     if (!st)
 328         return AVERROR(ENOMEM);
 329
 330     st->start_time = 0;
 331     st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
 332     st->codec->codec_tag  = buf[32];
 333     st->codec->codec_id   = ff_codec_get_id(ff_oma_codec_tags,
 334                                             st->codec->codec_tag);
 335
 336     switch (buf[32]) {
 337     case OMA_CODECID_ATRAC3:
 338         samplerate = ff_oma_srate_tab[(codec_params >> 13) & 7] * 100;
 339         if (!samplerate) {
 340             av_log(s, AV_LOG_ERROR, "Unsupported sample rate\n");
 341             return AVERROR_INVALIDDATA;
 342         }
 343         if (samplerate != 44100)
 344             avpriv_request_sample(s, "Sample rate %d", samplerate);
 345
 346         framesize = (codec_params & 0x3FF) * 8;
 347
 348         /* get stereo coding mode, 1 for joint-stereo */
 349         jsflag = (codec_params >> 17) & 1;
 350
 351         st->codec->channels    = 2;
 352         st->codec->channel_layout = AV_CH_LAYOUT_STEREO;
 353         st->codec->sample_rate = samplerate;
 354         st->codec->bit_rate    = st->codec->sample_rate * framesize * 8 / 1024;
 355
 356         /* fake the ATRAC3 extradata
 357          * (wav format, makes stream copy to wav work) */
 358         st->codec->extradata_size = 14;
 359         edata = av_mallocz(14 + FF_INPUT_BUFFER_PADDING_SIZE);
 360         if (!edata)
 361             return AVERROR(ENOMEM);
 362
 363         st->codec->extradata = edata;
 364         AV_WL16(&edata[0],  1);             // always 1
 365         AV_WL32(&edata[2],  samplerate);    // samples rate
 366         AV_WL16(&edata[6],  jsflag);        // coding mode
 367         AV_WL16(&edata[8],  jsflag);        // coding mode
 368         AV_WL16(&edata[10], 1);             // always 1
 369         // AV_WL16(&edata[12], 0);          // always 0
 370
 371         avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
 372         break;
 373     case OMA_CODECID_ATRAC3P:
 374         channel_id = (codec_params >> 10) & 7;
 375         if (!channel_id) {
 376             av_log(s, AV_LOG_ERROR,
 377                    "Invalid ATRAC-X channel id: %"PRIu32"\n", channel_id);
 378             return AVERROR_INVALIDDATA;
 379         }
 380         st->codec->channel_layout = ff_oma_chid_to_native_layout[channel_id - 1];
 381         st->codec->channels       = ff_oma_chid_to_num_channels[channel_id - 1];
 382         framesize = ((codec_params & 0x3FF) * 8) + 8;
 383         samplerate = ff_oma_srate_tab[(codec_params >> 13) & 7] * 100;
 384         if (!samplerate) {
 385             av_log(s, AV_LOG_ERROR, "Unsupported sample rate\n");
 386             return AVERROR_INVALIDDATA;
 387         }
 388         st->codec->sample_rate = samplerate;
 389         st->codec->bit_rate    = samplerate * framesize * 8 / 2048;
 390         avpriv_set_pts_info(st, 64, 1, samplerate);
 391         break;
 392     case OMA_CODECID_MP3:
 393         st->need_parsing = AVSTREAM_PARSE_FULL;
 394         framesize = 1024;
 395         break;
 396     case OMA_CODECID_LPCM:
 397         /* PCM 44.1 kHz 16 bit stereo big-endian */
 398         st->codec->channels = 2;
 399         st->codec->channel_layout = AV_CH_LAYOUT_STEREO;
 400         st->codec->sample_rate = 44100;
 401         framesize = 1024;
 402         /* bit rate = sample rate x PCM block align (= 4) x 8 */
 403         st->codec->bit_rate = st->codec->sample_rate * 32;
 404         st->codec->bits_per_coded_sample =
 405             av_get_bits_per_sample(st->codec->codec_id);
 406         avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
 407         break;
 408     default:
 409         av_log(s, AV_LOG_ERROR, "Unsupported codec %d!\n", buf[32]);
 410         return AVERROR(ENOSYS);
 411     }
 412
 413     st->codec->block_align = framesize;
 414
 415     return 0;
 416 }
 417
 418
 419 static int oma_read_packet(AVFormatContext *s, AVPacket *pkt)
 420 {
 421     OMAContext *oc = s->priv_data;
 422     int packet_size = s->streams[0]->codec->block_align;
 423     int ret = av_get_packet(s->pb, pkt, packet_size);
 424
 425     if (ret < packet_size)
 426         pkt->flags |= AV_PKT_FLAG_CORRUPT;
 427
 428     if (ret < 0)
 429         return ret;
 430     if (!ret)
 431         return AVERROR_EOF;
 432
 433     pkt->stream_index = 0;
 434
 435     if (oc->encrypted) {
 436         /* previous unencrypted block saved in IV for
 437          * the next packet (CBC mode) */
 438         if (ret == packet_size)
 439             av_des_crypt(&oc->av_des, pkt->data, pkt->data,
 440                          (packet_size >> 3), oc->iv, 1);
 441         else
 442             memset(oc->iv, 0, 8);
 443     }
 444
 445     return ret;
 446 }
 447
 448 static int oma_read_probe(AVProbeData *p)
 449 {
 450     const uint8_t *buf = p->buf;
 451     unsigned tag_len = 0;
 452
 453     if (p->buf_size >= ID3v2_HEADER_SIZE && ff_id3v2_match(buf, ID3v2_EA3_MAGIC))
 454         tag_len = ff_id3v2_tag_len(buf);
 455
 456     /* This check cannot overflow as tag_len has at most 28 bits */
 457     if (p->buf_size < tag_len + 5)
 458         /* EA3 header comes late, might be outside of the probe buffer */
 459         return tag_len ? AVPROBE_SCORE_EXTENSION : 0;
 460
 461     buf += tag_len;
 462
 463     if (!memcmp(buf, "EA3", 3) && !buf[4] && buf[5] == EA3_HEADER_SIZE)
 464         return AVPROBE_SCORE_MAX;
 465     else
 466         return 0;
 467 }
 468
 469 static int oma_read_seek(struct AVFormatContext *s,
 470                          int stream_index, int64_t timestamp, int flags)
 471 {
 472     OMAContext *oc = s->priv_data;
 473     int err = ff_pcm_read_seek(s, stream_index, timestamp, flags);
 474
 475     if (!oc->encrypted)
 476         return err;
 477
 478     /* readjust IV for CBC */
 479     if (err || avio_tell(s->pb) < oc->content_start)
 480         goto wipe;
 481     if ((err = avio_seek(s->pb, -8, SEEK_CUR)) < 0)
 482         goto wipe;
 483     if ((err = avio_read(s->pb, oc->iv, 8)) < 8) {
 484         if (err >= 0)
 485             err = AVERROR_EOF;
 486         goto wipe;
 487     }
 488
 489     return 0;
 490 wipe:
 491     memset(oc->iv, 0, 8);
 492     return err;
 493 }
 494
 495 AVInputFormat ff_oma_demuxer = {
 496     .name           = "oma",
 497     .long_name      = NULL_IF_CONFIG_SMALL("Sony OpenMG audio"),
 498     .priv_data_size = sizeof(OMAContext),
 499     .read_probe     = oma_read_probe,
 500     .read_header    = oma_read_header,
 501     .read_packet    = oma_read_packet,
 502     .read_seek      = oma_read_seek,
 503     .flags          = AVFMT_GENERIC_INDEX,
 504     .extensions     = "oma,omg,aa3",
 505     .codec_tag      = (const AVCodecTag* const []){ff_oma_codec_tags, 0},
 506 };