1 /*
2  * Matroska file demuxer
3  * Copyright (c) 2003-2008 The FFmpeg Project
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * Matroska file demuxer
25  * @author Ronald Bultje <rbultje@ronald.bitfreak.net>
26  * @author with a little help from Moritz Bunkus <moritz@bunkus.org>
27  * @author totally reworked by Aurelien Jacobs <aurel@gnuage.org>
28  * @see specs available on the Matroska project page: http://www.matroska.org/
29  */
30 
31 #include "config.h"
32 
33 #include <inttypes.h>
34 #include <stdio.h>
35 
36 #include "libavutil/avstring.h"
37 #include "libavutil/base64.h"
38 #include "libavutil/dict.h"
39 #include "libavutil/intfloat.h"
40 #include "libavutil/intreadwrite.h"
41 #if CONFIG_LZO
42 #include "libavutil/lzo.h"
43 #endif
44 #include "libavutil/mastering_display_metadata.h"
45 #include "libavutil/mathematics.h"
46 #include "libavutil/opt.h"
47 #include "libavutil/time_internal.h"
48 #include "libavutil/spherical.h"
49 
50 #include "libavcodec/bytestream.h"
51 #include "libavcodec/flac.h"
52 #include "libavcodec/mpeg4audio.h"
53 
54 #include "avformat.h"
55 #include "avio_internal.h"
56 #include "internal.h"
57 #include "isom.h"
58 #include "matroska.h"
59 #include "oggdec.h"
60 /* For ff_codec_get_id(). */
61 #include "riff.h"
62 #if CONFIG_SIPR_DECODER
63 #include "rmsipr.h"
64 #endif
65 
66 #if CONFIG_BZLIB
67 #include <bzlib.h>
68 #endif
69 #if CONFIG_ZLIB
70 #include <zlib.h>
71 #endif
72 
73 #include "qtpalette.h"
74 
75 #define EBML_UNKNOWN_LENGTH  UINT64_MAX /* EBML unknown length, in uint64_t */
76 #define NEEDS_CHECKING                2 /* Indicates that some error checks
77                                          * still need to be performed */
78 #define LEVEL_ENDED                   3 /* return value of ebml_parse when the
79                                          * syntax level used for parsing ended. */
80 #define SKIP_THRESHOLD      1024 * 1024 /* In non-seekable mode, if more than SKIP_THRESHOLD
81                                          * of unkown, potentially damaged data is encountered,
82                                          * it is considered an error. */
83 #define UNKNOWN_EQUIV         50 * 1024 /* An unknown element is considered equivalent
84                                          * to this many bytes of unknown data for the
85                                          * SKIP_THRESHOLD check. */
86 
87 typedef enum {
88     EBML_NONE,
89     EBML_UINT,
90     EBML_SINT,
91     EBML_FLOAT,
92     EBML_STR,
93     EBML_UTF8,
94     EBML_BIN,
95     EBML_NEST,
96     EBML_LEVEL1,
97     EBML_STOP,
98     EBML_TYPE_COUNT
99 } EbmlType;
100 
101 typedef const struct EbmlSyntax {
102     uint32_t id;
103     EbmlType type;
104     size_t list_elem_size;
105     size_t data_offset;
106     union {
107         int64_t     i;
108         uint64_t    u;
109         double      f;
110         const char *s;
111         const struct EbmlSyntax *n;
112     } def;
113 } EbmlSyntax;
114 
115 typedef struct EbmlList {
116     int nb_elem;
117     unsigned int alloc_elem_size;
118     void *elem;
119 } EbmlList;
120 
121 typedef struct EbmlBin {
122     int      size;
123     AVBufferRef *buf;
124     uint8_t *data;
125     int64_t  pos;
126 } EbmlBin;
127 
128 typedef struct Ebml {
129     uint64_t version;
130     uint64_t max_size;
131     uint64_t id_length;
132     char    *doctype;
133     uint64_t doctype_version;
134 } Ebml;
135 
136 typedef struct MatroskaTrackCompression {
137     uint64_t algo;
138     EbmlBin  settings;
139 } MatroskaTrackCompression;
140 
141 typedef struct MatroskaTrackEncryption {
142     uint64_t algo;
143     EbmlBin  key_id;
144 } MatroskaTrackEncryption;
145 
146 typedef struct MatroskaTrackEncoding {
147     uint64_t scope;
148     uint64_t type;
149     MatroskaTrackCompression compression;
150     MatroskaTrackEncryption encryption;
151 } MatroskaTrackEncoding;
152 
153 typedef struct MatroskaMasteringMeta {
154     double r_x;
155     double r_y;
156     double g_x;
157     double g_y;
158     double b_x;
159     double b_y;
160     double white_x;
161     double white_y;
162     double max_luminance;
163     double min_luminance;
164 } MatroskaMasteringMeta;
165 
166 typedef struct MatroskaTrackVideoColor {
167     uint64_t matrix_coefficients;
168     uint64_t bits_per_channel;
169     uint64_t chroma_sub_horz;
170     uint64_t chroma_sub_vert;
171     uint64_t cb_sub_horz;
172     uint64_t cb_sub_vert;
173     uint64_t chroma_siting_horz;
174     uint64_t chroma_siting_vert;
175     uint64_t range;
176     uint64_t transfer_characteristics;
177     uint64_t primaries;
178     uint64_t max_cll;
179     uint64_t max_fall;
180     MatroskaMasteringMeta mastering_meta;
181 } MatroskaTrackVideoColor;
182 
183 typedef struct MatroskaTrackVideoProjection {
184     uint64_t type;
185     EbmlBin private;
186     double yaw;
187     double pitch;
188     double roll;
189 } MatroskaTrackVideoProjection;
190 
191 typedef struct MatroskaTrackVideo {
192     double   frame_rate;
193     uint64_t display_width;
194     uint64_t display_height;
195     uint64_t pixel_width;
196     uint64_t pixel_height;
197     EbmlBin  color_space;
198     uint64_t display_unit;
199     uint64_t interlaced;
200     uint64_t field_order;
201     uint64_t stereo_mode;
202     uint64_t alpha_mode;
203     EbmlList color;
204     MatroskaTrackVideoProjection projection;
205 } MatroskaTrackVideo;
206 
207 typedef struct MatroskaTrackAudio {
208     double   samplerate;
209     double   out_samplerate;
210     uint64_t bitdepth;
211     uint64_t channels;
212 
213     /* real audio header (extracted from extradata) */
214     int      coded_framesize;
215     int      sub_packet_h;
216     int      frame_size;
217     int      sub_packet_size;
218     int      sub_packet_cnt;
219     int      pkt_cnt;
220     uint64_t buf_timecode;
221     uint8_t *buf;
222 } MatroskaTrackAudio;
223 
224 typedef struct MatroskaTrackPlane {
225     uint64_t uid;
226     uint64_t type;
227 } MatroskaTrackPlane;
228 
229 typedef struct MatroskaTrackOperation {
230     EbmlList combine_planes;
231 } MatroskaTrackOperation;
232 
233 typedef struct MatroskaTrack {
234     uint64_t num;
235     uint64_t uid;
236     uint64_t type;
237     char    *name;
238     char    *codec_id;
239     EbmlBin  codec_priv;
240     char    *language;
241     double time_scale;
242     uint64_t default_duration;
243     uint64_t flag_default;
244     uint64_t flag_forced;
245     uint64_t seek_preroll;
246     MatroskaTrackVideo video;
247     MatroskaTrackAudio audio;
248     MatroskaTrackOperation operation;
249     EbmlList encodings;
250     uint64_t codec_delay;
251     uint64_t codec_delay_in_track_tb;
252 
253     AVStream *stream;
254     int64_t end_timecode;
255     int ms_compat;
256     uint64_t max_block_additional_id;
257 
258     uint32_t palette[AVPALETTE_COUNT];
259     int has_palette;
260 } MatroskaTrack;
261 
262 typedef struct MatroskaAttachment {
263     uint64_t uid;
264     char *filename;
265     char *mime;
266     EbmlBin bin;
267 
268     AVStream *stream;
269 } MatroskaAttachment;
270 
271 typedef struct MatroskaChapter {
272     uint64_t start;
273     uint64_t end;
274     uint64_t uid;
275     char    *title;
276 
277     AVChapter *chapter;
278 } MatroskaChapter;
279 
280 typedef struct MatroskaIndexPos {
281     uint64_t track;
282     uint64_t pos;
283 } MatroskaIndexPos;
284 
285 typedef struct MatroskaIndex {
286     uint64_t time;
287     EbmlList pos;
288 } MatroskaIndex;
289 
290 typedef struct MatroskaTag {
291     char *name;
292     char *string;
293     char *lang;
294     uint64_t def;
295     EbmlList sub;
296 } MatroskaTag;
297 
298 typedef struct MatroskaTagTarget {
299     char    *type;
300     uint64_t typevalue;
301     uint64_t trackuid;
302     uint64_t chapteruid;
303     uint64_t attachuid;
304 } MatroskaTagTarget;
305 
306 typedef struct MatroskaTags {
307     MatroskaTagTarget target;
308     EbmlList tag;
309 } MatroskaTags;
310 
311 typedef struct MatroskaSeekhead {
312     uint64_t id;
313     uint64_t pos;
314 } MatroskaSeekhead;
315 
316 typedef struct MatroskaLevel {
317     uint64_t start;
318     uint64_t length;
319 } MatroskaLevel;
320 
321 typedef struct MatroskaBlock {
322     uint64_t duration;
323     int64_t  reference;
324     uint64_t non_simple;
325     EbmlBin  bin;
326     uint64_t additional_id;
327     EbmlBin  additional;
328     int64_t  discard_padding;
329 } MatroskaBlock;
330 
331 typedef struct MatroskaCluster {
332     MatroskaBlock block;
333     uint64_t timecode;
334     int64_t pos;
335 } MatroskaCluster;
336 
337 typedef struct MatroskaLevel1Element {
338     int64_t  pos;
339     uint32_t id;
340     int parsed;
341 } MatroskaLevel1Element;
342 
343 typedef struct MatroskaDemuxContext {
344     const AVClass *class;
345     AVFormatContext *ctx;
346 
347     /* EBML stuff */
348     MatroskaLevel levels[EBML_MAX_DEPTH];
349     int      num_levels;
350     uint32_t current_id;
351     int64_t  resync_pos;
352     int      unknown_count;
353 
354     uint64_t time_scale;
355     double   duration;
356     char    *title;
357     char    *muxingapp;
358     EbmlBin  date_utc;
359     EbmlList tracks;
360     EbmlList attachments;
361     EbmlList chapters;
362     EbmlList index;
363     EbmlList tags;
364     EbmlList seekhead;
365 
366     /* byte position of the segment inside the stream */
367     int64_t segment_start;
368 
369     /* the packet queue */
370     AVPacketList *queue;
371     AVPacketList *queue_end;
372 
373     int done;
374 
375     /* What to skip before effectively reading a packet. */
376     int skip_to_keyframe;
377     uint64_t skip_to_timecode;
378 
379     /* File has a CUES element, but we defer parsing until it is needed. */
380     int cues_parsing_deferred;
381 
382     /* Level1 elements and whether they were read yet */
383     MatroskaLevel1Element level1_elems[64];
384     int num_level1_elems;
385 
386     MatroskaCluster current_cluster;
387 
388     /* WebM DASH Manifest live flag */
389     int is_live;
390 
391     /* Bandwidth value for WebM DASH Manifest */
392     int bandwidth;
393 } MatroskaDemuxContext;
394 
395 #define CHILD_OF(parent) { .def = { .n = parent } }
396 
397 // The following forward declarations need their size because
398 // a tentative definition with internal linkage must not be an
399 // incomplete type (6.7.2 in C90, 6.9.2 in C99).
400 // Removing the sizes breaks MSVC.
401 static EbmlSyntax ebml_syntax[3], matroska_segment[9], matroska_track_video_color[15], matroska_track_video[19],
402                   matroska_track[27], matroska_track_encoding[6], matroska_track_encodings[2],
403                   matroska_track_combine_planes[2], matroska_track_operation[2], matroska_tracks[2],
404                   matroska_attachments[2], matroska_chapter_entry[9], matroska_chapter[6], matroska_chapters[2],
405                   matroska_index_entry[3], matroska_index[2], matroska_tag[3], matroska_tags[2], matroska_seekhead[2],
406                   matroska_blockadditions[2], matroska_blockgroup[8], matroska_cluster_parsing[8];
407 
408 static EbmlSyntax ebml_header[] = {
409     { EBML_ID_EBMLREADVERSION,    EBML_UINT, 0, offsetof(Ebml, version),         { .u = EBML_VERSION } },
410     { EBML_ID_EBMLMAXSIZELENGTH,  EBML_UINT, 0, offsetof(Ebml, max_size),        { .u = 8 } },
411     { EBML_ID_EBMLMAXIDLENGTH,    EBML_UINT, 0, offsetof(Ebml, id_length),       { .u = 4 } },
412     { EBML_ID_DOCTYPE,            EBML_STR,  0, offsetof(Ebml, doctype),         { .s = "(none)" } },
413     { EBML_ID_DOCTYPEREADVERSION, EBML_UINT, 0, offsetof(Ebml, doctype_version), { .u = 1 } },
414     { EBML_ID_EBMLVERSION,        EBML_NONE },
415     { EBML_ID_DOCTYPEVERSION,     EBML_NONE },
416     CHILD_OF(ebml_syntax)
417 };
418 
419 static EbmlSyntax ebml_syntax[] = {
420     { EBML_ID_HEADER,      EBML_NEST, 0, 0, { .n = ebml_header } },
421     { MATROSKA_ID_SEGMENT, EBML_STOP },
422     { 0 }
423 };
424 
425 static EbmlSyntax matroska_info[] = {
426     { MATROSKA_ID_TIMECODESCALE, EBML_UINT,  0, offsetof(MatroskaDemuxContext, time_scale), { .u = 1000000 } },
427     { MATROSKA_ID_DURATION,      EBML_FLOAT, 0, offsetof(MatroskaDemuxContext, duration) },
428     { MATROSKA_ID_TITLE,         EBML_UTF8,  0, offsetof(MatroskaDemuxContext, title) },
429     { MATROSKA_ID_WRITINGAPP,    EBML_NONE },
430     { MATROSKA_ID_MUXINGAPP,     EBML_UTF8, 0, offsetof(MatroskaDemuxContext, muxingapp) },
431     { MATROSKA_ID_DATEUTC,       EBML_BIN,  0, offsetof(MatroskaDemuxContext, date_utc) },
432     { MATROSKA_ID_SEGMENTUID,    EBML_NONE },
433     CHILD_OF(matroska_segment)
434 };
435 
436 static EbmlSyntax matroska_mastering_meta[] = {
437     { MATROSKA_ID_VIDEOCOLOR_RX, EBML_FLOAT, 0, offsetof(MatroskaMasteringMeta, r_x), { .f=-1 } },
438     { MATROSKA_ID_VIDEOCOLOR_RY, EBML_FLOAT, 0, offsetof(MatroskaMasteringMeta, r_y), { .f=-1 } },
439     { MATROSKA_ID_VIDEOCOLOR_GX, EBML_FLOAT, 0, offsetof(MatroskaMasteringMeta, g_x), { .f=-1 } },
440     { MATROSKA_ID_VIDEOCOLOR_GY, EBML_FLOAT, 0, offsetof(MatroskaMasteringMeta, g_y), { .f=-1 } },
441     { MATROSKA_ID_VIDEOCOLOR_BX, EBML_FLOAT, 0, offsetof(MatroskaMasteringMeta, b_x), { .f=-1 } },
442     { MATROSKA_ID_VIDEOCOLOR_BY, EBML_FLOAT, 0, offsetof(MatroskaMasteringMeta, b_y), { .f=-1 } },
443     { MATROSKA_ID_VIDEOCOLOR_WHITEX, EBML_FLOAT, 0, offsetof(MatroskaMasteringMeta, white_x), { .f=-1 } },
444     { MATROSKA_ID_VIDEOCOLOR_WHITEY, EBML_FLOAT, 0, offsetof(MatroskaMasteringMeta, white_y), { .f=-1 } },
445     { MATROSKA_ID_VIDEOCOLOR_LUMINANCEMIN, EBML_FLOAT, 0, offsetof(MatroskaMasteringMeta, min_luminance), { .f=-1 } },
446     { MATROSKA_ID_VIDEOCOLOR_LUMINANCEMAX, EBML_FLOAT, 0, offsetof(MatroskaMasteringMeta, max_luminance), { .f=-1 } },
447     CHILD_OF(matroska_track_video_color)
448 };
449 
450 static EbmlSyntax matroska_track_video_color[] = {
451     { MATROSKA_ID_VIDEOCOLORMATRIXCOEFF,      EBML_UINT, 0, offsetof(MatroskaTrackVideoColor, matrix_coefficients), { .u = AVCOL_SPC_UNSPECIFIED } },
452     { MATROSKA_ID_VIDEOCOLORBITSPERCHANNEL,   EBML_UINT, 0, offsetof(MatroskaTrackVideoColor, bits_per_channel), { .u=0 } },
453     { MATROSKA_ID_VIDEOCOLORCHROMASUBHORZ,    EBML_UINT, 0, offsetof(MatroskaTrackVideoColor, chroma_sub_horz), { .u=0 } },
454     { MATROSKA_ID_VIDEOCOLORCHROMASUBVERT,    EBML_UINT, 0, offsetof(MatroskaTrackVideoColor, chroma_sub_vert), { .u=0 } },
455     { MATROSKA_ID_VIDEOCOLORCBSUBHORZ,        EBML_UINT, 0, offsetof(MatroskaTrackVideoColor, cb_sub_horz), { .u=0 } },
456     { MATROSKA_ID_VIDEOCOLORCBSUBVERT,        EBML_UINT, 0, offsetof(MatroskaTrackVideoColor, cb_sub_vert), { .u=0 } },
457     { MATROSKA_ID_VIDEOCOLORCHROMASITINGHORZ, EBML_UINT, 0, offsetof(MatroskaTrackVideoColor, chroma_siting_horz), { .u = MATROSKA_COLOUR_CHROMASITINGHORZ_UNDETERMINED } },
458     { MATROSKA_ID_VIDEOCOLORCHROMASITINGVERT, EBML_UINT, 0, offsetof(MatroskaTrackVideoColor, chroma_siting_vert), { .u = MATROSKA_COLOUR_CHROMASITINGVERT_UNDETERMINED } },
459     { MATROSKA_ID_VIDEOCOLORRANGE,            EBML_UINT, 0, offsetof(MatroskaTrackVideoColor, range), { .u = AVCOL_RANGE_UNSPECIFIED } },
460     { MATROSKA_ID_VIDEOCOLORTRANSFERCHARACTERISTICS, EBML_UINT, 0, offsetof(MatroskaTrackVideoColor, transfer_characteristics), { .u = AVCOL_TRC_UNSPECIFIED } },
461     { MATROSKA_ID_VIDEOCOLORPRIMARIES,        EBML_UINT, 0, offsetof(MatroskaTrackVideoColor, primaries), { .u = AVCOL_PRI_UNSPECIFIED } },
462     { MATROSKA_ID_VIDEOCOLORMAXCLL,           EBML_UINT, 0, offsetof(MatroskaTrackVideoColor, max_cll), { .u=0 } },
463     { MATROSKA_ID_VIDEOCOLORMAXFALL,          EBML_UINT, 0, offsetof(MatroskaTrackVideoColor, max_fall), { .u=0 } },
464     { MATROSKA_ID_VIDEOCOLORMASTERINGMETA,    EBML_NEST, 0, offsetof(MatroskaTrackVideoColor, mastering_meta), { .n = matroska_mastering_meta } },
465     CHILD_OF(matroska_track_video)
466 };
467 
468 static EbmlSyntax matroska_track_video_projection[] = {
469     { MATROSKA_ID_VIDEOPROJECTIONTYPE,        EBML_UINT,  0, offsetof(MatroskaTrackVideoProjection, type), { .u = MATROSKA_VIDEO_PROJECTION_TYPE_RECTANGULAR } },
470     { MATROSKA_ID_VIDEOPROJECTIONPRIVATE,     EBML_BIN,   0, offsetof(MatroskaTrackVideoProjection, private) },
471     { MATROSKA_ID_VIDEOPROJECTIONPOSEYAW,     EBML_FLOAT, 0, offsetof(MatroskaTrackVideoProjection, yaw), { .f=0.0 } },
472     { MATROSKA_ID_VIDEOPROJECTIONPOSEPITCH,   EBML_FLOAT, 0, offsetof(MatroskaTrackVideoProjection, pitch), { .f=0.0 } },
473     { MATROSKA_ID_VIDEOPROJECTIONPOSEROLL,    EBML_FLOAT, 0, offsetof(MatroskaTrackVideoProjection, roll), { .f=0.0 } },
474     CHILD_OF(matroska_track_video)
475 };
476 
477 static EbmlSyntax matroska_track_video[] = {
478     { MATROSKA_ID_VIDEOFRAMERATE,      EBML_FLOAT, 0, offsetof(MatroskaTrackVideo, frame_rate) },
479     { MATROSKA_ID_VIDEODISPLAYWIDTH,   EBML_UINT,  0, offsetof(MatroskaTrackVideo, display_width), { .u=-1 } },
480     { MATROSKA_ID_VIDEODISPLAYHEIGHT,  EBML_UINT,  0, offsetof(MatroskaTrackVideo, display_height), { .u=-1 } },
481     { MATROSKA_ID_VIDEOPIXELWIDTH,     EBML_UINT,  0, offsetof(MatroskaTrackVideo, pixel_width) },
482     { MATROSKA_ID_VIDEOPIXELHEIGHT,    EBML_UINT,  0, offsetof(MatroskaTrackVideo, pixel_height) },
483     { MATROSKA_ID_VIDEOCOLORSPACE,     EBML_BIN,   0, offsetof(MatroskaTrackVideo, color_space) },
484     { MATROSKA_ID_VIDEOALPHAMODE,      EBML_UINT,  0, offsetof(MatroskaTrackVideo, alpha_mode) },
485     { MATROSKA_ID_VIDEOCOLOR,          EBML_NEST,  sizeof(MatroskaTrackVideoColor), offsetof(MatroskaTrackVideo, color), { .n = matroska_track_video_color } },
486     { MATROSKA_ID_VIDEOPROJECTION,     EBML_NEST,  0, offsetof(MatroskaTrackVideo, projection), { .n = matroska_track_video_projection } },
487     { MATROSKA_ID_VIDEOPIXELCROPB,     EBML_NONE },
488     { MATROSKA_ID_VIDEOPIXELCROPT,     EBML_NONE },
489     { MATROSKA_ID_VIDEOPIXELCROPL,     EBML_NONE },
490     { MATROSKA_ID_VIDEOPIXELCROPR,     EBML_NONE },
491     { MATROSKA_ID_VIDEODISPLAYUNIT,    EBML_UINT,  0, offsetof(MatroskaTrackVideo, display_unit), { .u= MATROSKA_VIDEO_DISPLAYUNIT_PIXELS } },
492     { MATROSKA_ID_VIDEOFLAGINTERLACED, EBML_UINT,  0, offsetof(MatroskaTrackVideo, interlaced),  { .u = MATROSKA_VIDEO_INTERLACE_FLAG_UNDETERMINED } },
493     { MATROSKA_ID_VIDEOFIELDORDER,     EBML_UINT,  0, offsetof(MatroskaTrackVideo, field_order), { .u = MATROSKA_VIDEO_FIELDORDER_UNDETERMINED } },
494     { MATROSKA_ID_VIDEOSTEREOMODE,     EBML_UINT,  0, offsetof(MatroskaTrackVideo, stereo_mode), { .u = MATROSKA_VIDEO_STEREOMODE_TYPE_NB } },
495     { MATROSKA_ID_VIDEOASPECTRATIO,    EBML_NONE },
496     CHILD_OF(matroska_track)
497 };
498 
499 static EbmlSyntax matroska_track_audio[] = {
500     { MATROSKA_ID_AUDIOSAMPLINGFREQ,    EBML_FLOAT, 0, offsetof(MatroskaTrackAudio, samplerate), { .f = 8000.0 } },
501     { MATROSKA_ID_AUDIOOUTSAMPLINGFREQ, EBML_FLOAT, 0, offsetof(MatroskaTrackAudio, out_samplerate) },
502     { MATROSKA_ID_AUDIOBITDEPTH,        EBML_UINT,  0, offsetof(MatroskaTrackAudio, bitdepth) },
503     { MATROSKA_ID_AUDIOCHANNELS,        EBML_UINT,  0, offsetof(MatroskaTrackAudio, channels),   { .u = 1 } },
504     CHILD_OF(matroska_track)
505 };
506 
507 static EbmlSyntax matroska_track_encoding_compression[] = {
508     { MATROSKA_ID_ENCODINGCOMPALGO,     EBML_UINT, 0, offsetof(MatroskaTrackCompression, algo), { .u = 0 } },
509     { MATROSKA_ID_ENCODINGCOMPSETTINGS, EBML_BIN,  0, offsetof(MatroskaTrackCompression, settings) },
510     CHILD_OF(matroska_track_encoding)
511 };
512 
513 static EbmlSyntax matroska_track_encoding_encryption[] = {
514     { MATROSKA_ID_ENCODINGENCALGO,        EBML_UINT, 0, offsetof(MatroskaTrackEncryption,algo), {.u = 0} },
515     { MATROSKA_ID_ENCODINGENCKEYID,       EBML_BIN, 0, offsetof(MatroskaTrackEncryption,key_id) },
516     { MATROSKA_ID_ENCODINGENCAESSETTINGS, EBML_NONE },
517     { MATROSKA_ID_ENCODINGSIGALGO,        EBML_NONE },
518     { MATROSKA_ID_ENCODINGSIGHASHALGO,    EBML_NONE },
519     { MATROSKA_ID_ENCODINGSIGKEYID,       EBML_NONE },
520     { MATROSKA_ID_ENCODINGSIGNATURE,      EBML_NONE },
521     CHILD_OF(matroska_track_encoding)
522 };
523 static EbmlSyntax matroska_track_encoding[] = {
524     { MATROSKA_ID_ENCODINGSCOPE,       EBML_UINT, 0, offsetof(MatroskaTrackEncoding, scope),       { .u = 1 } },
525     { MATROSKA_ID_ENCODINGTYPE,        EBML_UINT, 0, offsetof(MatroskaTrackEncoding, type),        { .u = 0 } },
526     { MATROSKA_ID_ENCODINGCOMPRESSION, EBML_NEST, 0, offsetof(MatroskaTrackEncoding, compression), { .n = matroska_track_encoding_compression } },
527     { MATROSKA_ID_ENCODINGENCRYPTION,  EBML_NEST, 0, offsetof(MatroskaTrackEncoding, encryption),  { .n = matroska_track_encoding_encryption } },
528     { MATROSKA_ID_ENCODINGORDER,       EBML_NONE },
529     CHILD_OF(matroska_track_encodings)
530 };
531 
532 static EbmlSyntax matroska_track_encodings[] = {
533     { MATROSKA_ID_TRACKCONTENTENCODING, EBML_NEST, sizeof(MatroskaTrackEncoding), offsetof(MatroskaTrack, encodings), { .n = matroska_track_encoding } },
534     CHILD_OF(matroska_track)
535 };
536 
537 static EbmlSyntax matroska_track_plane[] = {
538     { MATROSKA_ID_TRACKPLANEUID,  EBML_UINT, 0, offsetof(MatroskaTrackPlane,uid) },
539     { MATROSKA_ID_TRACKPLANETYPE, EBML_UINT, 0, offsetof(MatroskaTrackPlane,type) },
540     CHILD_OF(matroska_track_combine_planes)
541 };
542 
543 static EbmlSyntax matroska_track_combine_planes[] = {
544     { MATROSKA_ID_TRACKPLANE, EBML_NEST, sizeof(MatroskaTrackPlane), offsetof(MatroskaTrackOperation,combine_planes), {.n = matroska_track_plane} },
545     CHILD_OF(matroska_track_operation)
546 };
547 
548 static EbmlSyntax matroska_track_operation[] = {
549     { MATROSKA_ID_TRACKCOMBINEPLANES, EBML_NEST, 0, 0, {.n = matroska_track_combine_planes} },
550     CHILD_OF(matroska_track)
551 };
552 
553 static EbmlSyntax matroska_track[] = {
554     { MATROSKA_ID_TRACKNUMBER,           EBML_UINT,  0, offsetof(MatroskaTrack, num) },
555     { MATROSKA_ID_TRACKNAME,             EBML_UTF8,  0, offsetof(MatroskaTrack, name) },
556     { MATROSKA_ID_TRACKUID,              EBML_UINT,  0, offsetof(MatroskaTrack, uid) },
557     { MATROSKA_ID_TRACKTYPE,             EBML_UINT,  0, offsetof(MatroskaTrack, type) },
558     { MATROSKA_ID_CODECID,               EBML_STR,   0, offsetof(MatroskaTrack, codec_id) },
559     { MATROSKA_ID_CODECPRIVATE,          EBML_BIN,   0, offsetof(MatroskaTrack, codec_priv) },
560     { MATROSKA_ID_CODECDELAY,            EBML_UINT,  0, offsetof(MatroskaTrack, codec_delay) },
561     { MATROSKA_ID_TRACKLANGUAGE,         EBML_UTF8,  0, offsetof(MatroskaTrack, language),     { .s = "eng" } },
562     { MATROSKA_ID_TRACKDEFAULTDURATION,  EBML_UINT,  0, offsetof(MatroskaTrack, default_duration) },
563     { MATROSKA_ID_TRACKTIMECODESCALE,    EBML_FLOAT, 0, offsetof(MatroskaTrack, time_scale),   { .f = 1.0 } },
564     { MATROSKA_ID_TRACKFLAGDEFAULT,      EBML_UINT,  0, offsetof(MatroskaTrack, flag_default), { .u = 1 } },
565     { MATROSKA_ID_TRACKFLAGFORCED,       EBML_UINT,  0, offsetof(MatroskaTrack, flag_forced),  { .u = 0 } },
566     { MATROSKA_ID_TRACKVIDEO,            EBML_NEST,  0, offsetof(MatroskaTrack, video),        { .n = matroska_track_video } },
567     { MATROSKA_ID_TRACKAUDIO,            EBML_NEST,  0, offsetof(MatroskaTrack, audio),        { .n = matroska_track_audio } },
568     { MATROSKA_ID_TRACKOPERATION,        EBML_NEST,  0, offsetof(MatroskaTrack, operation),    { .n = matroska_track_operation } },
569     { MATROSKA_ID_TRACKCONTENTENCODINGS, EBML_NEST,  0, 0,                                     { .n = matroska_track_encodings } },
570     { MATROSKA_ID_TRACKMAXBLKADDID,      EBML_UINT,  0, offsetof(MatroskaTrack, max_block_additional_id) },
571     { MATROSKA_ID_SEEKPREROLL,           EBML_UINT,  0, offsetof(MatroskaTrack, seek_preroll) },
572     { MATROSKA_ID_TRACKFLAGENABLED,      EBML_NONE },
573     { MATROSKA_ID_TRACKFLAGLACING,       EBML_NONE },
574     { MATROSKA_ID_CODECNAME,             EBML_NONE },
575     { MATROSKA_ID_CODECDECODEALL,        EBML_NONE },
576     { MATROSKA_ID_CODECINFOURL,          EBML_NONE },
577     { MATROSKA_ID_CODECDOWNLOADURL,      EBML_NONE },
578     { MATROSKA_ID_TRACKMINCACHE,         EBML_NONE },
579     { MATROSKA_ID_TRACKMAXCACHE,         EBML_NONE },
580     CHILD_OF(matroska_tracks)
581 };
582 
583 static EbmlSyntax matroska_tracks[] = {
584     { MATROSKA_ID_TRACKENTRY, EBML_NEST, sizeof(MatroskaTrack), offsetof(MatroskaDemuxContext, tracks), { .n = matroska_track } },
585     CHILD_OF(matroska_segment)
586 };
587 
588 static EbmlSyntax matroska_attachment[] = {
589     { MATROSKA_ID_FILEUID,      EBML_UINT, 0, offsetof(MatroskaAttachment, uid) },
590     { MATROSKA_ID_FILENAME,     EBML_UTF8, 0, offsetof(MatroskaAttachment, filename) },
591     { MATROSKA_ID_FILEMIMETYPE, EBML_STR,  0, offsetof(MatroskaAttachment, mime) },
592     { MATROSKA_ID_FILEDATA,     EBML_BIN,  0, offsetof(MatroskaAttachment, bin) },
593     { MATROSKA_ID_FILEDESC,     EBML_NONE },
594     CHILD_OF(matroska_attachments)
595 };
596 
597 static EbmlSyntax matroska_attachments[] = {
598     { MATROSKA_ID_ATTACHEDFILE, EBML_NEST, sizeof(MatroskaAttachment), offsetof(MatroskaDemuxContext, attachments), { .n = matroska_attachment } },
599     CHILD_OF(matroska_segment)
600 };
601 
602 static EbmlSyntax matroska_chapter_display[] = {
603     { MATROSKA_ID_CHAPSTRING,  EBML_UTF8, 0, offsetof(MatroskaChapter, title) },
604     { MATROSKA_ID_CHAPLANG,    EBML_NONE },
605     { MATROSKA_ID_CHAPCOUNTRY, EBML_NONE },
606     CHILD_OF(matroska_chapter_entry)
607 };
608 
609 static EbmlSyntax matroska_chapter_entry[] = {
610     { MATROSKA_ID_CHAPTERTIMESTART,   EBML_UINT, 0, offsetof(MatroskaChapter, start), { .u = AV_NOPTS_VALUE } },
611     { MATROSKA_ID_CHAPTERTIMEEND,     EBML_UINT, 0, offsetof(MatroskaChapter, end),   { .u = AV_NOPTS_VALUE } },
612     { MATROSKA_ID_CHAPTERUID,         EBML_UINT, 0, offsetof(MatroskaChapter, uid) },
613     { MATROSKA_ID_CHAPTERDISPLAY,     EBML_NEST, 0,                        0,         { .n = matroska_chapter_display } },
614     { MATROSKA_ID_CHAPTERFLAGHIDDEN,  EBML_NONE },
615     { MATROSKA_ID_CHAPTERFLAGENABLED, EBML_NONE },
616     { MATROSKA_ID_CHAPTERPHYSEQUIV,   EBML_NONE },
617     { MATROSKA_ID_CHAPTERATOM,        EBML_NONE },
618     CHILD_OF(matroska_chapter)
619 };
620 
621 static EbmlSyntax matroska_chapter[] = {
622     { MATROSKA_ID_CHAPTERATOM,        EBML_NEST, sizeof(MatroskaChapter), offsetof(MatroskaDemuxContext, chapters), { .n = matroska_chapter_entry } },
623     { MATROSKA_ID_EDITIONUID,         EBML_NONE },
624     { MATROSKA_ID_EDITIONFLAGHIDDEN,  EBML_NONE },
625     { MATROSKA_ID_EDITIONFLAGDEFAULT, EBML_NONE },
626     { MATROSKA_ID_EDITIONFLAGORDERED, EBML_NONE },
627     CHILD_OF(matroska_chapters)
628 };
629 
630 static EbmlSyntax matroska_chapters[] = {
631     { MATROSKA_ID_EDITIONENTRY, EBML_NEST, 0, 0, { .n = matroska_chapter } },
632     CHILD_OF(matroska_segment)
633 };
634 
635 static EbmlSyntax matroska_index_pos[] = {
636     { MATROSKA_ID_CUETRACK,           EBML_UINT, 0, offsetof(MatroskaIndexPos, track) },
637     { MATROSKA_ID_CUECLUSTERPOSITION, EBML_UINT, 0, offsetof(MatroskaIndexPos, pos) },
638     { MATROSKA_ID_CUERELATIVEPOSITION,EBML_NONE },
639     { MATROSKA_ID_CUEDURATION,        EBML_NONE },
640     { MATROSKA_ID_CUEBLOCKNUMBER,     EBML_NONE },
641     CHILD_OF(matroska_index_entry)
642 };
643 
644 static EbmlSyntax matroska_index_entry[] = {
645     { MATROSKA_ID_CUETIME,          EBML_UINT, 0,                        offsetof(MatroskaIndex, time) },
646     { MATROSKA_ID_CUETRACKPOSITION, EBML_NEST, sizeof(MatroskaIndexPos), offsetof(MatroskaIndex, pos), { .n = matroska_index_pos } },
647     CHILD_OF(matroska_index)
648 };
649 
650 static EbmlSyntax matroska_index[] = {
651     { MATROSKA_ID_POINTENTRY, EBML_NEST, sizeof(MatroskaIndex), offsetof(MatroskaDemuxContext, index), { .n = matroska_index_entry } },
652     CHILD_OF(matroska_segment)
653 };
654 
655 static EbmlSyntax matroska_simpletag[] = {
656     { MATROSKA_ID_TAGNAME,        EBML_UTF8, 0,                   offsetof(MatroskaTag, name) },
657     { MATROSKA_ID_TAGSTRING,      EBML_UTF8, 0,                   offsetof(MatroskaTag, string) },
658     { MATROSKA_ID_TAGLANG,        EBML_STR,  0,                   offsetof(MatroskaTag, lang), { .s = "und" } },
659     { MATROSKA_ID_TAGDEFAULT,     EBML_UINT, 0,                   offsetof(MatroskaTag, def) },
660     { MATROSKA_ID_TAGDEFAULT_BUG, EBML_UINT, 0,                   offsetof(MatroskaTag, def) },
661     { MATROSKA_ID_SIMPLETAG,      EBML_NEST, sizeof(MatroskaTag), offsetof(MatroskaTag, sub),  { .n = matroska_simpletag } },
662     CHILD_OF(matroska_tag)
663 };
664 
665 static EbmlSyntax matroska_tagtargets[] = {
666     { MATROSKA_ID_TAGTARGETS_TYPE,       EBML_STR,  0, offsetof(MatroskaTagTarget, type) },
667     { MATROSKA_ID_TAGTARGETS_TYPEVALUE,  EBML_UINT, 0, offsetof(MatroskaTagTarget, typevalue), { .u = 50 } },
668     { MATROSKA_ID_TAGTARGETS_TRACKUID,   EBML_UINT, 0, offsetof(MatroskaTagTarget, trackuid) },
669     { MATROSKA_ID_TAGTARGETS_CHAPTERUID, EBML_UINT, 0, offsetof(MatroskaTagTarget, chapteruid) },
670     { MATROSKA_ID_TAGTARGETS_ATTACHUID,  EBML_UINT, 0, offsetof(MatroskaTagTarget, attachuid) },
671     CHILD_OF(matroska_tag)
672 };
673 
674 static EbmlSyntax matroska_tag[] = {
675     { MATROSKA_ID_SIMPLETAG,  EBML_NEST, sizeof(MatroskaTag), offsetof(MatroskaTags, tag),    { .n = matroska_simpletag } },
676     { MATROSKA_ID_TAGTARGETS, EBML_NEST, 0,                   offsetof(MatroskaTags, target), { .n = matroska_tagtargets } },
677     CHILD_OF(matroska_tags)
678 };
679 
680 static EbmlSyntax matroska_tags[] = {
681     { MATROSKA_ID_TAG, EBML_NEST, sizeof(MatroskaTags), offsetof(MatroskaDemuxContext, tags), { .n = matroska_tag } },
682     CHILD_OF(matroska_segment)
683 };
684 
685 static EbmlSyntax matroska_seekhead_entry[] = {
686     { MATROSKA_ID_SEEKID,       EBML_UINT, 0, offsetof(MatroskaSeekhead, id) },
687     { MATROSKA_ID_SEEKPOSITION, EBML_UINT, 0, offsetof(MatroskaSeekhead, pos), { .u = -1 } },
688     CHILD_OF(matroska_seekhead)
689 };
690 
691 static EbmlSyntax matroska_seekhead[] = {
692     { MATROSKA_ID_SEEKENTRY, EBML_NEST, sizeof(MatroskaSeekhead), offsetof(MatroskaDemuxContext, seekhead), { .n = matroska_seekhead_entry } },
693     CHILD_OF(matroska_segment)
694 };
695 
696 static EbmlSyntax matroska_segment[] = {
697     { MATROSKA_ID_CLUSTER,     EBML_STOP },
698     { MATROSKA_ID_INFO,        EBML_LEVEL1, 0, 0, { .n = matroska_info } },
699     { MATROSKA_ID_TRACKS,      EBML_LEVEL1, 0, 0, { .n = matroska_tracks } },
700     { MATROSKA_ID_ATTACHMENTS, EBML_LEVEL1, 0, 0, { .n = matroska_attachments } },
701     { MATROSKA_ID_CHAPTERS,    EBML_LEVEL1, 0, 0, { .n = matroska_chapters } },
702     { MATROSKA_ID_CUES,        EBML_LEVEL1, 0, 0, { .n = matroska_index } },
703     { MATROSKA_ID_TAGS,        EBML_LEVEL1, 0, 0, { .n = matroska_tags } },
704     { MATROSKA_ID_SEEKHEAD,    EBML_LEVEL1, 0, 0, { .n = matroska_seekhead } },
705     { 0 }   /* We don't want to go back to level 0, so don't add the parent. */
706 };
707 
708 static EbmlSyntax matroska_segments[] = {
709     { MATROSKA_ID_SEGMENT, EBML_NEST, 0, 0, { .n = matroska_segment } },
710     { 0 }
711 };
712 
713 static EbmlSyntax matroska_blockmore[] = {
714     { MATROSKA_ID_BLOCKADDID,      EBML_UINT, 0, offsetof(MatroskaBlock,additional_id), { .u = 1 } },
715     { MATROSKA_ID_BLOCKADDITIONAL, EBML_BIN,  0, offsetof(MatroskaBlock,additional) },
716     CHILD_OF(matroska_blockadditions)
717 };
718 
719 static EbmlSyntax matroska_blockadditions[] = {
720     { MATROSKA_ID_BLOCKMORE, EBML_NEST, 0, 0, {.n = matroska_blockmore} },
721     CHILD_OF(matroska_blockgroup)
722 };
723 
724 static EbmlSyntax matroska_blockgroup[] = {
725     { MATROSKA_ID_BLOCK,          EBML_BIN,  0, offsetof(MatroskaBlock, bin) },
726     { MATROSKA_ID_BLOCKADDITIONS, EBML_NEST, 0, 0, { .n = matroska_blockadditions} },
727     { MATROSKA_ID_BLOCKDURATION,  EBML_UINT, 0, offsetof(MatroskaBlock, duration) },
728     { MATROSKA_ID_DISCARDPADDING, EBML_SINT, 0, offsetof(MatroskaBlock, discard_padding) },
729     { MATROSKA_ID_BLOCKREFERENCE, EBML_SINT, 0, offsetof(MatroskaBlock, reference), { .i = INT64_MIN } },
730     { MATROSKA_ID_CODECSTATE,     EBML_NONE },
731     {                          1, EBML_UINT, 0, offsetof(MatroskaBlock, non_simple), { .u = 1 } },
732     CHILD_OF(matroska_cluster_parsing)
733 };
734 
735 // The following array contains SimpleBlock and BlockGroup twice
736 // in order to reuse the other values for matroska_cluster_enter.
737 static EbmlSyntax matroska_cluster_parsing[] = {
738     { MATROSKA_ID_SIMPLEBLOCK,     EBML_BIN,  0, offsetof(MatroskaBlock, bin) },
739     { MATROSKA_ID_BLOCKGROUP,      EBML_NEST, 0, 0, { .n = matroska_blockgroup } },
740     { MATROSKA_ID_CLUSTERTIMECODE, EBML_UINT, 0, offsetof(MatroskaCluster, timecode) },
741     { MATROSKA_ID_SIMPLEBLOCK,     EBML_STOP },
742     { MATROSKA_ID_BLOCKGROUP,      EBML_STOP },
743     { MATROSKA_ID_CLUSTERPOSITION, EBML_NONE },
744     { MATROSKA_ID_CLUSTERPREVSIZE, EBML_NONE },
745     CHILD_OF(matroska_segment)
746 };
747 
748 static EbmlSyntax matroska_cluster_enter[] = {
749     { MATROSKA_ID_CLUSTER,     EBML_NEST, 0, 0, { .n = &matroska_cluster_parsing[2] } },
750     { 0 }
751 };
752 #undef CHILD_OF
753 
754 static const char *const matroska_doctypes[] = { "matroska", "webm" };
755 
756 static int matroska_read_close(AVFormatContext *s);
757 
758 /*
759  * This function prepares the status for parsing of level 1 elements.
760  */
matroska_reset_status(MatroskaDemuxContext * matroska,uint32_t id,int64_t position)761 static int matroska_reset_status(MatroskaDemuxContext *matroska,
762                                  uint32_t id, int64_t position)
763 {
764     if (position >= 0) {
765         int64_t err = avio_seek(matroska->ctx->pb, position, SEEK_SET);
766         if (err < 0)
767             return err;
768     }
769 
770     matroska->current_id    = id;
771     matroska->num_levels    = 1;
772     matroska->unknown_count = 0;
773     matroska->resync_pos = avio_tell(matroska->ctx->pb);
774     if (id)
775         matroska->resync_pos -= (av_log2(id) + 7) / 8;
776 
777     return 0;
778 }
779 
matroska_resync(MatroskaDemuxContext * matroska,int64_t last_pos)780 static int matroska_resync(MatroskaDemuxContext *matroska, int64_t last_pos)
781 {
782     AVIOContext *pb = matroska->ctx->pb;
783     uint32_t id;
784 
785     /* Try to seek to the last position to resync from. If this doesn't work,
786      * we resync from the earliest position available: The start of the buffer. */
787     if (last_pos < avio_tell(pb) && avio_seek(pb, last_pos + 1, SEEK_SET) < 0) {
788         av_log(matroska->ctx, AV_LOG_WARNING,
789                "Seek to desired resync point failed. Seeking to "
790                "earliest point available instead.\n");
791         avio_seek(pb, FFMAX(avio_tell(pb) + (pb->buffer - pb->buf_ptr),
792                             last_pos + 1), SEEK_SET);
793     }
794 
795     id = avio_rb32(pb);
796 
797     // try to find a toplevel element
798     while (!avio_feof(pb)) {
799         if (id == MATROSKA_ID_INFO     || id == MATROSKA_ID_TRACKS      ||
800             id == MATROSKA_ID_CUES     || id == MATROSKA_ID_TAGS        ||
801             id == MATROSKA_ID_SEEKHEAD || id == MATROSKA_ID_ATTACHMENTS ||
802             id == MATROSKA_ID_CLUSTER  || id == MATROSKA_ID_CHAPTERS) {
803             /* Prepare the context for parsing of a level 1 element. */
804             matroska_reset_status(matroska, id, -1);
805             /* Given that we are here means that an error has occurred,
806              * so treat the segment as unknown length in order not to
807              * discard valid data that happens to be beyond the designated
808              * end of the segment. */
809             matroska->levels[0].length = EBML_UNKNOWN_LENGTH;
810             return 0;
811         }
812         id = (id << 8) | avio_r8(pb);
813     }
814 
815     matroska->done = 1;
816     return pb->error ? pb->error : AVERROR_EOF;
817 }
818 
819 /*
820  * Read: an "EBML number", which is defined as a variable-length
821  * array of bytes. The first byte indicates the length by giving a
822  * number of 0-bits followed by a one. The position of the first
823  * "one" bit inside the first byte indicates the length of this
824  * number.
825  * Returns: number of bytes read, < 0 on error
826  */
ebml_read_num(MatroskaDemuxContext * matroska,AVIOContext * pb,int max_size,uint64_t * number,int eof_forbidden)827 static int ebml_read_num(MatroskaDemuxContext *matroska, AVIOContext *pb,
828                          int max_size, uint64_t *number, int eof_forbidden)
829 {
830     int read, n = 1;
831     uint64_t total;
832     int64_t pos;
833 
834     /* The first byte tells us the length in bytes - except when it is zero. */
835     total = avio_r8(pb);
836     if (pb->eof_reached)
837         goto err;
838 
839     /* get the length of the EBML number */
840     read = 8 - ff_log2_tab[total];
841 
842     if (!total || read > max_size) {
843         pos = avio_tell(pb) - 1;
844         if (!total) {
845             av_log(matroska->ctx, AV_LOG_ERROR,
846                    "0x00 at pos %"PRId64" (0x%"PRIx64") invalid as first byte "
847                    "of an EBML number\n", pos, pos);
848         } else {
849             av_log(matroska->ctx, AV_LOG_ERROR,
850                    "Length %d indicated by an EBML number's first byte 0x%02x "
851                    "at pos %"PRId64" (0x%"PRIx64") exceeds max length %d.\n",
852                    read, (uint8_t) total, pos, pos, max_size);
853         }
854         return AVERROR_INVALIDDATA;
855     }
856 
857     /* read out length */
858     total ^= 1 << ff_log2_tab[total];
859     while (n++ < read)
860         total = (total << 8) | avio_r8(pb);
861 
862     if (pb->eof_reached) {
863         eof_forbidden = 1;
864         goto err;
865     }
866 
867     *number = total;
868 
869     return read;
870 
871 err:
872     pos = avio_tell(pb);
873     if (pb->error) {
874         av_log(matroska->ctx, AV_LOG_ERROR,
875                "Read error at pos. %"PRIu64" (0x%"PRIx64")\n",
876                pos, pos);
877         return pb->error;
878     }
879     if (eof_forbidden) {
880         av_log(matroska->ctx, AV_LOG_ERROR, "File ended prematurely "
881                "at pos. %"PRIu64" (0x%"PRIx64")\n", pos, pos);
882         return AVERROR(EIO);
883     }
884     return AVERROR_EOF;
885 }
886 
887 /**
888  * Read a EBML length value.
889  * This needs special handling for the "unknown length" case which has multiple
890  * encodings.
891  */
ebml_read_length(MatroskaDemuxContext * matroska,AVIOContext * pb,uint64_t * number)892 static int ebml_read_length(MatroskaDemuxContext *matroska, AVIOContext *pb,
893                             uint64_t *number)
894 {
895     int res = ebml_read_num(matroska, pb, 8, number, 1);
896     if (res > 0 && *number + 1 == 1ULL << (7 * res))
897         *number = EBML_UNKNOWN_LENGTH;
898     return res;
899 }
900 
901 /*
902  * Read the next element as an unsigned int.
903  * Returns NEEDS_CHECKING.
904  */
ebml_read_uint(AVIOContext * pb,int size,uint64_t * num)905 static int ebml_read_uint(AVIOContext *pb, int size, uint64_t *num)
906 {
907     int n = 0;
908 
909     /* big-endian ordering; build up number */
910     *num = 0;
911     while (n++ < size)
912         *num = (*num << 8) | avio_r8(pb);
913 
914     return NEEDS_CHECKING;
915 }
916 
917 /*
918  * Read the next element as a signed int.
919  * Returns NEEDS_CHECKING.
920  */
ebml_read_sint(AVIOContext * pb,int size,int64_t * num)921 static int ebml_read_sint(AVIOContext *pb, int size, int64_t *num)
922 {
923     int n = 1;
924 
925     if (size == 0) {
926         *num = 0;
927     } else {
928         *num = sign_extend(avio_r8(pb), 8);
929 
930         /* big-endian ordering; build up number */
931         while (n++ < size)
932             *num = ((uint64_t)*num << 8) | avio_r8(pb);
933     }
934 
935     return NEEDS_CHECKING;
936 }
937 
938 /*
939  * Read the next element as a float.
940  * Returns NEEDS_CHECKING or < 0 on obvious failure.
941  */
ebml_read_float(AVIOContext * pb,int size,double * num)942 static int ebml_read_float(AVIOContext *pb, int size, double *num)
943 {
944     if (size == 0)
945         *num = 0;
946     else if (size == 4)
947         *num = av_int2float(avio_rb32(pb));
948     else if (size == 8)
949         *num = av_int2double(avio_rb64(pb));
950     else
951         return AVERROR_INVALIDDATA;
952 
953     return NEEDS_CHECKING;
954 }
955 
956 /*
957  * Read the next element as an ASCII string.
958  * 0 is success, < 0 or NEEDS_CHECKING is failure.
959  */
ebml_read_ascii(AVIOContext * pb,int size,char ** str)960 static int ebml_read_ascii(AVIOContext *pb, int size, char **str)
961 {
962     char *res;
963     int ret;
964 
965     /* EBML strings are usually not 0-terminated, so we allocate one
966      * byte more, read the string and NULL-terminate it ourselves. */
967     if (!(res = av_malloc(size + 1)))
968         return AVERROR(ENOMEM);
969     if ((ret = avio_read(pb, (uint8_t *) res, size)) != size) {
970         av_free(res);
971         return ret < 0 ? ret : NEEDS_CHECKING;
972     }
973     (res)[size] = '\0';
974     av_free(*str);
975     *str = res;
976 
977     return 0;
978 }
979 
980 /*
981  * Read the next element as binary data.
982  * 0 is success, < 0 or NEEDS_CHECKING is failure.
983  */
ebml_read_binary(AVIOContext * pb,int length,int64_t pos,EbmlBin * bin)984 static int ebml_read_binary(AVIOContext *pb, int length,
985                             int64_t pos, EbmlBin *bin)
986 {
987     int ret;
988 
989     ret = av_buffer_realloc(&bin->buf, length + AV_INPUT_BUFFER_PADDING_SIZE);
990     if (ret < 0)
991         return ret;
992     memset(bin->buf->data + length, 0, AV_INPUT_BUFFER_PADDING_SIZE);
993 
994     bin->data = bin->buf->data;
995     bin->size = length;
996     bin->pos  = pos;
997     if ((ret = avio_read(pb, bin->data, length)) != length) {
998         av_buffer_unref(&bin->buf);
999         bin->data = NULL;
1000         bin->size = 0;
1001         return ret < 0 ? ret : NEEDS_CHECKING;
1002     }
1003 
1004     return 0;
1005 }
1006 
1007 /*
1008  * Read the next element, but only the header. The contents
1009  * are supposed to be sub-elements which can be read separately.
1010  * 0 is success, < 0 is failure.
1011  */
ebml_read_master(MatroskaDemuxContext * matroska,uint64_t length,int64_t pos)1012 static int ebml_read_master(MatroskaDemuxContext *matroska,
1013                             uint64_t length, int64_t pos)
1014 {
1015     MatroskaLevel *level;
1016 
1017     if (matroska->num_levels >= EBML_MAX_DEPTH) {
1018         av_log(matroska->ctx, AV_LOG_ERROR,
1019                "File moves beyond max. allowed depth (%d)\n", EBML_MAX_DEPTH);
1020         return AVERROR(ENOSYS);
1021     }
1022 
1023     level         = &matroska->levels[matroska->num_levels++];
1024     level->start  = pos;
1025     level->length = length;
1026 
1027     return 0;
1028 }
1029 
1030 /*
1031  * Read a signed "EBML number"
1032  * Return: number of bytes processed, < 0 on error
1033  */
matroska_ebmlnum_sint(MatroskaDemuxContext * matroska,AVIOContext * pb,int64_t * num)1034 static int matroska_ebmlnum_sint(MatroskaDemuxContext *matroska,
1035                                  AVIOContext *pb, int64_t *num)
1036 {
1037     uint64_t unum;
1038     int res;
1039 
1040     /* read as unsigned number first */
1041     if ((res = ebml_read_num(matroska, pb, 8, &unum, 1)) < 0)
1042         return res;
1043 
1044     /* make signed (weird way) */
1045     *num = unum - ((1LL << (7 * res - 1)) - 1);
1046 
1047     return res;
1048 }
1049 
1050 static int ebml_parse(MatroskaDemuxContext *matroska,
1051                       EbmlSyntax *syntax, void *data);
1052 
ebml_parse_id(EbmlSyntax * syntax,uint32_t id)1053 static EbmlSyntax *ebml_parse_id(EbmlSyntax *syntax, uint32_t id)
1054 {
1055     int i;
1056 
1057     // Whoever touches this should be aware of the duplication
1058     // existing in matroska_cluster_parsing.
1059     for (i = 0; syntax[i].id; i++)
1060         if (id == syntax[i].id)
1061             break;
1062 
1063     return &syntax[i];
1064 }
1065 
ebml_parse_nest(MatroskaDemuxContext * matroska,EbmlSyntax * syntax,void * data)1066 static int ebml_parse_nest(MatroskaDemuxContext *matroska, EbmlSyntax *syntax,
1067                            void *data)
1068 {
1069     int res;
1070 
1071     if (data) {
1072         for (int i = 0; syntax[i].id; i++)
1073             switch (syntax[i].type) {
1074             case EBML_UINT:
1075                 *(uint64_t *) ((char *) data + syntax[i].data_offset) = syntax[i].def.u;
1076                 break;
1077             case EBML_SINT:
1078                 *(int64_t *) ((char *) data + syntax[i].data_offset) = syntax[i].def.i;
1079                 break;
1080             case EBML_FLOAT:
1081                 *(double *) ((char *) data + syntax[i].data_offset) = syntax[i].def.f;
1082                 break;
1083             case EBML_STR:
1084             case EBML_UTF8:
1085                 // the default may be NULL
1086                 if (syntax[i].def.s) {
1087                     uint8_t **dst = (uint8_t **) ((uint8_t *) data + syntax[i].data_offset);
1088                     *dst = av_strdup(syntax[i].def.s);
1089                     if (!*dst)
1090                         return AVERROR(ENOMEM);
1091                 }
1092                 break;
1093             }
1094 
1095         if (!matroska->levels[matroska->num_levels - 1].length) {
1096             matroska->num_levels--;
1097             return 0;
1098         }
1099     }
1100 
1101     do {
1102         res = ebml_parse(matroska, syntax, data);
1103     } while (!res);
1104 
1105     return res == LEVEL_ENDED ? 0 : res;
1106 }
1107 
is_ebml_id_valid(uint32_t id)1108 static int is_ebml_id_valid(uint32_t id)
1109 {
1110     // Due to endian nonsense in Matroska, the highest byte with any bits set
1111     // will contain the leading length bit. This bit in turn identifies the
1112     // total byte length of the element by its position within the byte.
1113     unsigned int bits = av_log2(id);
1114     return id && (bits + 7) / 8 ==  (8 - bits % 8);
1115 }
1116 
1117 /*
1118  * Allocate and return the entry for the level1 element with the given ID. If
1119  * an entry already exists, return the existing entry.
1120  */
matroska_find_level1_elem(MatroskaDemuxContext * matroska,uint32_t id)1121 static MatroskaLevel1Element *matroska_find_level1_elem(MatroskaDemuxContext *matroska,
1122                                                         uint32_t id)
1123 {
1124     int i;
1125     MatroskaLevel1Element *elem;
1126 
1127     if (!is_ebml_id_valid(id))
1128         return NULL;
1129 
1130     // Some files link to all clusters; useless.
1131     if (id == MATROSKA_ID_CLUSTER)
1132         return NULL;
1133 
1134     // There can be multiple seekheads.
1135     if (id != MATROSKA_ID_SEEKHEAD) {
1136         for (i = 0; i < matroska->num_level1_elems; i++) {
1137             if (matroska->level1_elems[i].id == id)
1138                 return &matroska->level1_elems[i];
1139         }
1140     }
1141 
1142     // Only a completely broken file would have more elements.
1143     // It also provides a low-effort way to escape from circular seekheads
1144     // (every iteration will add a level1 entry).
1145     if (matroska->num_level1_elems >= FF_ARRAY_ELEMS(matroska->level1_elems)) {
1146         av_log(matroska->ctx, AV_LOG_ERROR, "Too many level1 elements or circular seekheads.\n");
1147         return NULL;
1148     }
1149 
1150     elem = &matroska->level1_elems[matroska->num_level1_elems++];
1151     *elem = (MatroskaLevel1Element){.id = id};
1152 
1153     return elem;
1154 }
1155 
ebml_parse(MatroskaDemuxContext * matroska,EbmlSyntax * syntax,void * data)1156 static int ebml_parse(MatroskaDemuxContext *matroska,
1157                       EbmlSyntax *syntax, void *data)
1158 {
1159     static const uint64_t max_lengths[EBML_TYPE_COUNT] = {
1160         // Forbid unknown-length EBML_NONE elements.
1161         [EBML_NONE]  = EBML_UNKNOWN_LENGTH - 1,
1162         [EBML_UINT]  = 8,
1163         [EBML_SINT]  = 8,
1164         [EBML_FLOAT] = 8,
1165         // max. 16 MB for strings
1166         [EBML_STR]   = 0x1000000,
1167         [EBML_UTF8]  = 0x1000000,
1168         // max. 256 MB for binary data
1169         [EBML_BIN]   = 0x10000000,
1170         // no limits for anything else
1171     };
1172     AVIOContext *pb = matroska->ctx->pb;
1173     uint32_t id;
1174     uint64_t length;
1175     int64_t pos = avio_tell(pb), pos_alt;
1176     int res, update_pos = 1, level_check;
1177     MatroskaLevel1Element *level1_elem;
1178     MatroskaLevel *level = matroska->num_levels ? &matroska->levels[matroska->num_levels - 1] : NULL;
1179 
1180     if (!matroska->current_id) {
1181         uint64_t id;
1182         res = ebml_read_num(matroska, pb, 4, &id, 0);
1183         if (res < 0) {
1184             if (pb->eof_reached && res == AVERROR_EOF) {
1185                 if (matroska->is_live)
1186                     // in live mode, finish parsing if EOF is reached.
1187                     return 1;
1188                 if (level && pos == avio_tell(pb)) {
1189                     if (level->length == EBML_UNKNOWN_LENGTH) {
1190                         // Unknown-length levels automatically end at EOF.
1191                         matroska->num_levels--;
1192                         return LEVEL_ENDED;
1193                     } else {
1194                         av_log(matroska->ctx, AV_LOG_ERROR, "File ended prematurely "
1195                                "at pos. %"PRIu64" (0x%"PRIx64")\n", pos, pos);
1196                     }
1197                 }
1198             }
1199             return res;
1200         }
1201         matroska->current_id = id | 1 << 7 * res;
1202         pos_alt = pos + res;
1203     } else {
1204         pos_alt = pos;
1205         pos    -= (av_log2(matroska->current_id) + 7) / 8;
1206     }
1207 
1208     id = matroska->current_id;
1209 
1210     syntax = ebml_parse_id(syntax, id);
1211     if (!syntax->id && id != EBML_ID_VOID && id != EBML_ID_CRC32) {
1212         if (level && level->length == EBML_UNKNOWN_LENGTH) {
1213             // Unknown-length levels end when an element from an upper level
1214             // in the hierarchy is encountered.
1215             while (syntax->def.n) {
1216                 syntax = ebml_parse_id(syntax->def.n, id);
1217                 if (syntax->id) {
1218                     matroska->num_levels--;
1219                     return LEVEL_ENDED;
1220                 }
1221             };
1222         }
1223 
1224         av_log(matroska->ctx, AV_LOG_DEBUG, "Unknown entry 0x%"PRIX32" at pos. "
1225                                             "%"PRId64"\n", id, pos);
1226         update_pos = 0; /* Don't update resync_pos as an error might have happened. */
1227     }
1228 
1229     if (data) {
1230         data = (char *) data + syntax->data_offset;
1231         if (syntax->list_elem_size) {
1232             EbmlList *list = data;
1233             void *newelem;
1234 
1235             if ((unsigned)list->nb_elem + 1 >= UINT_MAX / syntax->list_elem_size)
1236                 return AVERROR(ENOMEM);
1237             newelem = av_fast_realloc(list->elem,
1238                                       &list->alloc_elem_size,
1239                                       (list->nb_elem + 1) * syntax->list_elem_size);
1240             if (!newelem)
1241                 return AVERROR(ENOMEM);
1242             list->elem = newelem;
1243             data = (char *) list->elem + list->nb_elem * syntax->list_elem_size;
1244             memset(data, 0, syntax->list_elem_size);
1245             list->nb_elem++;
1246         }
1247     }
1248 
1249     if (syntax->type != EBML_STOP) {
1250         matroska->current_id = 0;
1251         if ((res = ebml_read_length(matroska, pb, &length)) < 0)
1252             return res;
1253 
1254         pos_alt += res;
1255 
1256         if (matroska->num_levels > 0) {
1257             if (length != EBML_UNKNOWN_LENGTH &&
1258                 level->length != EBML_UNKNOWN_LENGTH) {
1259                 uint64_t elem_end = pos_alt + length,
1260                         level_end = level->start + level->length;
1261 
1262                 if (elem_end < level_end) {
1263                     level_check = 0;
1264                 } else if (elem_end == level_end) {
1265                     level_check = LEVEL_ENDED;
1266                 } else {
1267                     av_log(matroska->ctx, AV_LOG_ERROR,
1268                            "Element at 0x%"PRIx64" ending at 0x%"PRIx64" exceeds "
1269                            "containing master element ending at 0x%"PRIx64"\n",
1270                            pos, elem_end, level_end);
1271                     return AVERROR_INVALIDDATA;
1272                 }
1273             } else if (length != EBML_UNKNOWN_LENGTH) {
1274                 level_check = 0;
1275             } else if (level->length != EBML_UNKNOWN_LENGTH) {
1276                 av_log(matroska->ctx, AV_LOG_ERROR, "Unknown-sized element "
1277                        "at 0x%"PRIx64" inside parent with finite size\n", pos);
1278                 return AVERROR_INVALIDDATA;
1279             } else {
1280                 level_check = 0;
1281                 if (id != MATROSKA_ID_CLUSTER && (syntax->type == EBML_LEVEL1
1282                                               ||  syntax->type == EBML_NEST)) {
1283                     // According to the current specifications only clusters and
1284                     // segments are allowed to be unknown-length. We also accept
1285                     // other unknown-length master elements.
1286                     av_log(matroska->ctx, AV_LOG_WARNING,
1287                            "Found unknown-length element 0x%"PRIX32" other than "
1288                            "a cluster at 0x%"PRIx64". Spec-incompliant, but "
1289                            "parsing will nevertheless be attempted.\n", id, pos);
1290                     update_pos = -1;
1291                 }
1292             }
1293         } else
1294             level_check = 0;
1295 
1296         if (max_lengths[syntax->type] && length > max_lengths[syntax->type]) {
1297             if (length != EBML_UNKNOWN_LENGTH) {
1298                 av_log(matroska->ctx, AV_LOG_ERROR,
1299                        "Invalid length 0x%"PRIx64" > 0x%"PRIx64" for element "
1300                        "with ID 0x%"PRIX32" at 0x%"PRIx64"\n",
1301                        length, max_lengths[syntax->type], id, pos);
1302             } else if (syntax->type != EBML_NONE) {
1303                 av_log(matroska->ctx, AV_LOG_ERROR,
1304                        "Element with ID 0x%"PRIX32" at pos. 0x%"PRIx64" has "
1305                        "unknown length, yet the length of an element of its "
1306                        "type must be known.\n", id, pos);
1307             } else {
1308                 av_log(matroska->ctx, AV_LOG_ERROR,
1309                        "Found unknown-length element with ID 0x%"PRIX32" at "
1310                        "pos. 0x%"PRIx64" for which no syntax for parsing is "
1311                        "available.\n", id, pos);
1312             }
1313             return AVERROR_INVALIDDATA;
1314         }
1315 
1316         if (!(pb->seekable & AVIO_SEEKABLE_NORMAL)) {
1317             // Loosing sync will likely manifest itself as encountering unknown
1318             // elements which are not reliably distinguishable from elements
1319             // belonging to future extensions of the format.
1320             // We use a heuristic to detect such situations: If the current
1321             // element is not expected at the current syntax level and there
1322             // were only a few unknown elements in a row, then the element is
1323             // skipped or considered defective based upon the length of the
1324             // current element (i.e. how much would be skipped); if there were
1325             // more than a few skipped elements in a row and skipping the current
1326             // element would lead us more than SKIP_THRESHOLD away from the last
1327             // known good position, then it is inferred that an error occurred.
1328             // The dependency on the number of unknown elements in a row exists
1329             // because the distance to the last known good position is
1330             // automatically big if the last parsed element was big.
1331             // In both cases, each unknown element is considered equivalent to
1332             // UNKNOWN_EQUIV of skipped bytes for the check.
1333             // The whole check is only done for non-seekable output, because
1334             // in this situation skipped data can't simply be rechecked later.
1335             // This is especially important when using unkown length elements
1336             // as the check for whether a child exceeds its containing master
1337             // element is not effective in this situation.
1338             if (update_pos) {
1339                 matroska->unknown_count = 0;
1340             } else {
1341                 int64_t dist = length + UNKNOWN_EQUIV * matroska->unknown_count++;
1342 
1343                 if (matroska->unknown_count > 3)
1344                     dist += pos_alt - matroska->resync_pos;
1345 
1346                 if (dist > SKIP_THRESHOLD) {
1347                     av_log(matroska->ctx, AV_LOG_ERROR,
1348                            "Unknown element %"PRIX32" at pos. 0x%"PRIx64" with "
1349                            "length 0x%"PRIx64" considered as invalid data. Last "
1350                            "known good position 0x%"PRIx64", %d unknown elements"
1351                            " in a row\n", id, pos, length, matroska->resync_pos,
1352                            matroska->unknown_count);
1353                     return AVERROR_INVALIDDATA;
1354                 }
1355             }
1356         }
1357 
1358         if (update_pos > 0) {
1359             // We have found an element that is allowed at this place
1360             // in the hierarchy and it passed all checks, so treat the beginning
1361             // of the element as the "last known good" position.
1362             matroska->resync_pos = pos;
1363         }
1364 
1365         if (!data && length != EBML_UNKNOWN_LENGTH)
1366             goto skip;
1367     }
1368 
1369     switch (syntax->type) {
1370     case EBML_UINT:
1371         res = ebml_read_uint(pb, length, data);
1372         break;
1373     case EBML_SINT:
1374         res = ebml_read_sint(pb, length, data);
1375         break;
1376     case EBML_FLOAT:
1377         res = ebml_read_float(pb, length, data);
1378         break;
1379     case EBML_STR:
1380     case EBML_UTF8:
1381         res = ebml_read_ascii(pb, length, data);
1382         break;
1383     case EBML_BIN:
1384         res = ebml_read_binary(pb, length, pos_alt, data);
1385         break;
1386     case EBML_LEVEL1:
1387     case EBML_NEST:
1388         if ((res = ebml_read_master(matroska, length, pos_alt)) < 0)
1389             return res;
1390         if (id == MATROSKA_ID_SEGMENT)
1391             matroska->segment_start = pos_alt;
1392         if (id == MATROSKA_ID_CUES)
1393             matroska->cues_parsing_deferred = 0;
1394         if (syntax->type == EBML_LEVEL1 &&
1395             (level1_elem = matroska_find_level1_elem(matroska, syntax->id))) {
1396             if (!level1_elem->pos) {
1397                 // Zero is not a valid position for a level 1 element.
1398                 level1_elem->pos = pos;
1399             } else if (level1_elem->pos != pos)
1400                 av_log(matroska->ctx, AV_LOG_ERROR, "Duplicate element\n");
1401             level1_elem->parsed = 1;
1402         }
1403         if (res = ebml_parse_nest(matroska, syntax->def.n, data))
1404             return res;
1405         break;
1406     case EBML_STOP:
1407         return 1;
1408     skip:
1409     default:
1410         if (length) {
1411             int64_t res2;
1412             if (ffio_limit(pb, length) != length) {
1413                 // ffio_limit emits its own error message,
1414                 // so we don't have to.
1415                 return AVERROR(EIO);
1416             }
1417             if ((res2 = avio_skip(pb, length - 1)) >= 0) {
1418                 // avio_skip might take us past EOF. We check for this
1419                 // by skipping only length - 1 bytes, reading a byte and
1420                 // checking the error flags. This is done in order to check
1421                 // that the element has been properly skipped even when
1422                 // no filesize (that ffio_limit relies on) is available.
1423                 avio_r8(pb);
1424                 res = NEEDS_CHECKING;
1425             } else
1426                 res = res2;
1427         } else
1428             res = 0;
1429     }
1430     if (res) {
1431         if (res == NEEDS_CHECKING) {
1432             if (pb->eof_reached) {
1433                 if (pb->error)
1434                     res = pb->error;
1435                 else
1436                     res = AVERROR_EOF;
1437             } else
1438                 goto level_check;
1439         }
1440 
1441         if (res == AVERROR_INVALIDDATA)
1442             av_log(matroska->ctx, AV_LOG_ERROR, "Invalid element\n");
1443         else if (res == AVERROR(EIO))
1444             av_log(matroska->ctx, AV_LOG_ERROR, "Read error\n");
1445         else if (res == AVERROR_EOF) {
1446             av_log(matroska->ctx, AV_LOG_ERROR, "File ended prematurely\n");
1447             res = AVERROR(EIO);
1448         }
1449 
1450         return res;
1451     }
1452 
1453 level_check:
1454     if (level_check == LEVEL_ENDED && matroska->num_levels) {
1455         level = &matroska->levels[matroska->num_levels - 1];
1456         pos   = avio_tell(pb);
1457 
1458         // Given that pos >= level->start no check for
1459         // level->length != EBML_UNKNOWN_LENGTH is necessary.
1460         while (matroska->num_levels && pos == level->start + level->length) {
1461             matroska->num_levels--;
1462             level--;
1463         }
1464     }
1465 
1466     return level_check;
1467 }
1468 
ebml_free(EbmlSyntax * syntax,void * data)1469 static void ebml_free(EbmlSyntax *syntax, void *data)
1470 {
1471     int i, j;
1472     for (i = 0; syntax[i].id; i++) {
1473         void *data_off = (char *) data + syntax[i].data_offset;
1474         switch (syntax[i].type) {
1475         case EBML_STR:
1476         case EBML_UTF8:
1477             av_freep(data_off);
1478             break;
1479         case EBML_BIN:
1480             av_buffer_unref(&((EbmlBin *) data_off)->buf);
1481             break;
1482         case EBML_LEVEL1:
1483         case EBML_NEST:
1484             if (syntax[i].list_elem_size) {
1485                 EbmlList *list = data_off;
1486                 char *ptr = list->elem;
1487                 for (j = 0; j < list->nb_elem;
1488                      j++, ptr += syntax[i].list_elem_size)
1489                     ebml_free(syntax[i].def.n, ptr);
1490                 av_freep(&list->elem);
1491                 list->nb_elem = 0;
1492                 list->alloc_elem_size = 0;
1493             } else
1494                 ebml_free(syntax[i].def.n, data_off);
1495         default:
1496             break;
1497         }
1498     }
1499 }
1500 
1501 /*
1502  * Autodetecting...
1503  */
matroska_probe(const AVProbeData * p)1504 static int matroska_probe(const AVProbeData *p)
1505 {
1506     uint64_t total = 0;
1507     int len_mask = 0x80, size = 1, n = 1, i;
1508 
1509     /* EBML header? */
1510     if (AV_RB32(p->buf) != EBML_ID_HEADER)
1511         return 0;
1512 
1513     /* length of header */
1514     total = p->buf[4];
1515     while (size <= 8 && !(total & len_mask)) {
1516         size++;
1517         len_mask >>= 1;
1518     }
1519     if (size > 8)
1520         return 0;
1521     total &= (len_mask - 1);
1522     while (n < size)
1523         total = (total << 8) | p->buf[4 + n++];
1524 
1525     if (total + 1 == 1ULL << (7 * size)){
1526         /* Unknown-length header - simply parse the whole buffer. */
1527         total = p->buf_size - 4 - size;
1528     } else {
1529         /* Does the probe data contain the whole header? */
1530         if (p->buf_size < 4 + size + total)
1531             return 0;
1532     }
1533 
1534     /* The header should contain a known document type. For now,
1535      * we don't parse the whole header but simply check for the
1536      * availability of that array of characters inside the header.
1537      * Not fully fool-proof, but good enough. */
1538     for (i = 0; i < FF_ARRAY_ELEMS(matroska_doctypes); i++) {
1539         size_t probelen = strlen(matroska_doctypes[i]);
1540         if (total < probelen)
1541             continue;
1542         for (n = 4 + size; n <= 4 + size + total - probelen; n++)
1543             if (!memcmp(p->buf + n, matroska_doctypes[i], probelen))
1544                 return AVPROBE_SCORE_MAX;
1545     }
1546 
1547     // probably valid EBML header but no recognized doctype
1548     return AVPROBE_SCORE_EXTENSION;
1549 }
1550 
matroska_find_track_by_num(MatroskaDemuxContext * matroska,int num)1551 static MatroskaTrack *matroska_find_track_by_num(MatroskaDemuxContext *matroska,
1552                                                  int num)
1553 {
1554     MatroskaTrack *tracks = matroska->tracks.elem;
1555     int i;
1556 
1557     for (i = 0; i < matroska->tracks.nb_elem; i++)
1558         if (tracks[i].num == num)
1559             return &tracks[i];
1560 
1561     av_log(matroska->ctx, AV_LOG_ERROR, "Invalid track number %d\n", num);
1562     return NULL;
1563 }
1564 
matroska_decode_buffer(uint8_t ** buf,int * buf_size,MatroskaTrack * track)1565 static int matroska_decode_buffer(uint8_t **buf, int *buf_size,
1566                                   MatroskaTrack *track)
1567 {
1568     MatroskaTrackEncoding *encodings = track->encodings.elem;
1569     uint8_t *data = *buf;
1570     int isize = *buf_size;
1571     uint8_t *pkt_data = NULL;
1572     uint8_t av_unused *newpktdata;
1573     int pkt_size = isize;
1574     int result = 0;
1575     int olen;
1576 
1577     if (pkt_size >= 10000000U)
1578         return AVERROR_INVALIDDATA;
1579 
1580     switch (encodings[0].compression.algo) {
1581     case MATROSKA_TRACK_ENCODING_COMP_HEADERSTRIP:
1582     {
1583         int header_size = encodings[0].compression.settings.size;
1584         uint8_t *header = encodings[0].compression.settings.data;
1585 
1586         if (header_size && !header) {
1587             av_log(NULL, AV_LOG_ERROR, "Compression size but no data in headerstrip\n");
1588             return -1;
1589         }
1590 
1591         if (!header_size)
1592             return 0;
1593 
1594         pkt_size = isize + header_size;
1595         pkt_data = av_malloc(pkt_size + AV_INPUT_BUFFER_PADDING_SIZE);
1596         if (!pkt_data)
1597             return AVERROR(ENOMEM);
1598 
1599         memcpy(pkt_data, header, header_size);
1600         memcpy(pkt_data + header_size, data, isize);
1601         break;
1602     }
1603 #if CONFIG_LZO
1604     case MATROSKA_TRACK_ENCODING_COMP_LZO:
1605         do {
1606             int insize = isize;
1607             olen       = pkt_size *= 3;
1608             newpktdata = av_realloc(pkt_data, pkt_size + AV_LZO_OUTPUT_PADDING
1609                                                        + AV_INPUT_BUFFER_PADDING_SIZE);
1610             if (!newpktdata) {
1611                 result = AVERROR(ENOMEM);
1612                 goto failed;
1613             }
1614             pkt_data = newpktdata;
1615             result   = av_lzo1x_decode(pkt_data, &olen, data, &insize);
1616         } while (result == AV_LZO_OUTPUT_FULL && pkt_size < 10000000);
1617         if (result) {
1618             result = AVERROR_INVALIDDATA;
1619             goto failed;
1620         }
1621         pkt_size -= olen;
1622         break;
1623 #endif
1624 #if CONFIG_ZLIB
1625     case MATROSKA_TRACK_ENCODING_COMP_ZLIB:
1626     {
1627         z_stream zstream = { 0 };
1628         if (inflateInit(&zstream) != Z_OK)
1629             return -1;
1630         zstream.next_in  = data;
1631         zstream.avail_in = isize;
1632         do {
1633             pkt_size  *= 3;
1634             newpktdata = av_realloc(pkt_data, pkt_size + AV_INPUT_BUFFER_PADDING_SIZE);
1635             if (!newpktdata) {
1636                 inflateEnd(&zstream);
1637                 result = AVERROR(ENOMEM);
1638                 goto failed;
1639             }
1640             pkt_data          = newpktdata;
1641             zstream.avail_out = pkt_size - zstream.total_out;
1642             zstream.next_out  = pkt_data + zstream.total_out;
1643             result = inflate(&zstream, Z_NO_FLUSH);
1644         } while (result == Z_OK && pkt_size < 10000000);
1645         pkt_size = zstream.total_out;
1646         inflateEnd(&zstream);
1647         if (result != Z_STREAM_END) {
1648             if (result == Z_MEM_ERROR)
1649                 result = AVERROR(ENOMEM);
1650             else
1651                 result = AVERROR_INVALIDDATA;
1652             goto failed;
1653         }
1654         break;
1655     }
1656 #endif
1657 #if CONFIG_BZLIB
1658     case MATROSKA_TRACK_ENCODING_COMP_BZLIB:
1659     {
1660         bz_stream bzstream = { 0 };
1661         if (BZ2_bzDecompressInit(&bzstream, 0, 0) != BZ_OK)
1662             return -1;
1663         bzstream.next_in  = data;
1664         bzstream.avail_in = isize;
1665         do {
1666             pkt_size  *= 3;
1667             newpktdata = av_realloc(pkt_data, pkt_size + AV_INPUT_BUFFER_PADDING_SIZE);
1668             if (!newpktdata) {
1669                 BZ2_bzDecompressEnd(&bzstream);
1670                 result = AVERROR(ENOMEM);
1671                 goto failed;
1672             }
1673             pkt_data           = newpktdata;
1674             bzstream.avail_out = pkt_size - bzstream.total_out_lo32;
1675             bzstream.next_out  = pkt_data + bzstream.total_out_lo32;
1676             result = BZ2_bzDecompress(&bzstream);
1677         } while (result == BZ_OK && pkt_size < 10000000);
1678         pkt_size = bzstream.total_out_lo32;
1679         BZ2_bzDecompressEnd(&bzstream);
1680         if (result != BZ_STREAM_END) {
1681             if (result == BZ_MEM_ERROR)
1682                 result = AVERROR(ENOMEM);
1683             else
1684                 result = AVERROR_INVALIDDATA;
1685             goto failed;
1686         }
1687         break;
1688     }
1689 #endif
1690     default:
1691         return AVERROR_INVALIDDATA;
1692     }
1693 
1694     memset(pkt_data + pkt_size, 0, AV_INPUT_BUFFER_PADDING_SIZE);
1695 
1696     *buf      = pkt_data;
1697     *buf_size = pkt_size;
1698     return 0;
1699 
1700 failed:
1701     av_free(pkt_data);
1702     return result;
1703 }
1704 
matroska_convert_tag(AVFormatContext * s,EbmlList * list,AVDictionary ** metadata,char * prefix)1705 static void matroska_convert_tag(AVFormatContext *s, EbmlList *list,
1706                                  AVDictionary **metadata, char *prefix)
1707 {
1708     MatroskaTag *tags = list->elem;
1709     char key[1024];
1710     int i;
1711 
1712     for (i = 0; i < list->nb_elem; i++) {
1713         const char *lang = tags[i].lang &&
1714                            strcmp(tags[i].lang, "und") ? tags[i].lang : NULL;
1715 
1716         if (!tags[i].name) {
1717             av_log(s, AV_LOG_WARNING, "Skipping invalid tag with no TagName.\n");
1718             continue;
1719         }
1720         if (prefix)
1721             snprintf(key, sizeof(key), "%s/%s", prefix, tags[i].name);
1722         else
1723             av_strlcpy(key, tags[i].name, sizeof(key));
1724         if (tags[i].def || !lang) {
1725             av_dict_set(metadata, key, tags[i].string, 0);
1726             if (tags[i].sub.nb_elem)
1727                 matroska_convert_tag(s, &tags[i].sub, metadata, key);
1728         }
1729         if (lang) {
1730             av_strlcat(key, "-", sizeof(key));
1731             av_strlcat(key, lang, sizeof(key));
1732             av_dict_set(metadata, key, tags[i].string, 0);
1733             if (tags[i].sub.nb_elem)
1734                 matroska_convert_tag(s, &tags[i].sub, metadata, key);
1735         }
1736     }
1737     ff_metadata_conv(metadata, NULL, ff_mkv_metadata_conv);
1738 }
1739 
matroska_convert_tags(AVFormatContext * s)1740 static void matroska_convert_tags(AVFormatContext *s)
1741 {
1742     MatroskaDemuxContext *matroska = s->priv_data;
1743     MatroskaTags *tags = matroska->tags.elem;
1744     int i, j;
1745 
1746     for (i = 0; i < matroska->tags.nb_elem; i++) {
1747         if (tags[i].target.attachuid) {
1748             MatroskaAttachment *attachment = matroska->attachments.elem;
1749             int found = 0;
1750             for (j = 0; j < matroska->attachments.nb_elem; j++) {
1751                 if (attachment[j].uid == tags[i].target.attachuid &&
1752                     attachment[j].stream) {
1753                     matroska_convert_tag(s, &tags[i].tag,
1754                                          &attachment[j].stream->metadata, NULL);
1755                     found = 1;
1756                 }
1757             }
1758             if (!found) {
1759                 av_log(NULL, AV_LOG_WARNING,
1760                        "The tags at index %d refer to a "
1761                        "non-existent attachment %"PRId64".\n",
1762                        i, tags[i].target.attachuid);
1763             }
1764         } else if (tags[i].target.chapteruid) {
1765             MatroskaChapter *chapter = matroska->chapters.elem;
1766             int found = 0;
1767             for (j = 0; j < matroska->chapters.nb_elem; j++) {
1768                 if (chapter[j].uid == tags[i].target.chapteruid &&
1769                     chapter[j].chapter) {
1770                     matroska_convert_tag(s, &tags[i].tag,
1771                                          &chapter[j].chapter->metadata, NULL);
1772                     found = 1;
1773                 }
1774             }
1775             if (!found) {
1776                 av_log(NULL, AV_LOG_WARNING,
1777                        "The tags at index %d refer to a non-existent chapter "
1778                        "%"PRId64".\n",
1779                        i, tags[i].target.chapteruid);
1780             }
1781         } else if (tags[i].target.trackuid) {
1782             MatroskaTrack *track = matroska->tracks.elem;
1783             int found = 0;
1784             for (j = 0; j < matroska->tracks.nb_elem; j++) {
1785                 if (track[j].uid == tags[i].target.trackuid &&
1786                     track[j].stream) {
1787                     matroska_convert_tag(s, &tags[i].tag,
1788                                          &track[j].stream->metadata, NULL);
1789                     found = 1;
1790                }
1791             }
1792             if (!found) {
1793                 av_log(NULL, AV_LOG_WARNING,
1794                        "The tags at index %d refer to a non-existent track "
1795                        "%"PRId64".\n",
1796                        i, tags[i].target.trackuid);
1797             }
1798         } else {
1799             matroska_convert_tag(s, &tags[i].tag, &s->metadata,
1800                                  tags[i].target.type);
1801         }
1802     }
1803 }
1804 
matroska_parse_seekhead_entry(MatroskaDemuxContext * matroska,int64_t pos)1805 static int matroska_parse_seekhead_entry(MatroskaDemuxContext *matroska,
1806                                          int64_t pos)
1807 {
1808     uint32_t saved_id  = matroska->current_id;
1809     int64_t before_pos = avio_tell(matroska->ctx->pb);
1810     int ret = 0;
1811 
1812     /* seek */
1813     if (avio_seek(matroska->ctx->pb, pos, SEEK_SET) == pos) {
1814         /* We don't want to lose our seekhead level, so we add
1815          * a dummy. This is a crude hack. */
1816         if (matroska->num_levels == EBML_MAX_DEPTH) {
1817             av_log(matroska->ctx, AV_LOG_INFO,
1818                    "Max EBML element depth (%d) reached, "
1819                    "cannot parse further.\n", EBML_MAX_DEPTH);
1820             ret = AVERROR_INVALIDDATA;
1821         } else {
1822             matroska->levels[matroska->num_levels] = (MatroskaLevel) { 0, EBML_UNKNOWN_LENGTH };
1823             matroska->num_levels++;
1824             matroska->current_id                   = 0;
1825 
1826             ret = ebml_parse(matroska, matroska_segment, matroska);
1827             if (ret == LEVEL_ENDED) {
1828                 /* This can only happen if the seek brought us beyond EOF. */
1829                 ret = AVERROR_EOF;
1830             }
1831         }
1832     }
1833     /* Seek back - notice that in all instances where this is used
1834      * it is safe to set the level to 1. */
1835     matroska_reset_status(matroska, saved_id, before_pos);
1836 
1837     return ret;
1838 }
1839 
matroska_execute_seekhead(MatroskaDemuxContext * matroska)1840 static void matroska_execute_seekhead(MatroskaDemuxContext *matroska)
1841 {
1842     EbmlList *seekhead_list = &matroska->seekhead;
1843     int i;
1844 
1845     // we should not do any seeking in the streaming case
1846     if (!(matroska->ctx->pb->seekable & AVIO_SEEKABLE_NORMAL))
1847         return;
1848 
1849     for (i = 0; i < seekhead_list->nb_elem; i++) {
1850         MatroskaSeekhead *seekheads = seekhead_list->elem;
1851         uint32_t id = seekheads[i].id;
1852         int64_t pos = seekheads[i].pos + matroska->segment_start;
1853 
1854         MatroskaLevel1Element *elem = matroska_find_level1_elem(matroska, id);
1855         if (!elem || elem->parsed)
1856             continue;
1857 
1858         elem->pos = pos;
1859 
1860         // defer cues parsing until we actually need cue data.
1861         if (id == MATROSKA_ID_CUES)
1862             continue;
1863 
1864         if (matroska_parse_seekhead_entry(matroska, pos) < 0) {
1865             // mark index as broken
1866             matroska->cues_parsing_deferred = -1;
1867             break;
1868         }
1869 
1870         elem->parsed = 1;
1871     }
1872 }
1873 
matroska_add_index_entries(MatroskaDemuxContext * matroska)1874 static void matroska_add_index_entries(MatroskaDemuxContext *matroska)
1875 {
1876     EbmlList *index_list;
1877     MatroskaIndex *index;
1878     uint64_t index_scale = 1;
1879     int i, j;
1880 
1881     if (matroska->ctx->flags & AVFMT_FLAG_IGNIDX)
1882         return;
1883 
1884     index_list = &matroska->index;
1885     index      = index_list->elem;
1886     if (index_list->nb_elem < 2)
1887         return;
1888     if (index[1].time > 1E14 / matroska->time_scale) {
1889         av_log(matroska->ctx, AV_LOG_WARNING, "Dropping apparently-broken index.\n");
1890         return;
1891     }
1892     for (i = 0; i < index_list->nb_elem; i++) {
1893         EbmlList *pos_list    = &index[i].pos;
1894         MatroskaIndexPos *pos = pos_list->elem;
1895         for (j = 0; j < pos_list->nb_elem; j++) {
1896             MatroskaTrack *track = matroska_find_track_by_num(matroska,
1897                                                               pos[j].track);
1898             if (track && track->stream)
1899                 av_add_index_entry(track->stream,
1900                                    pos[j].pos + matroska->segment_start,
1901                                    index[i].time / index_scale, 0, 0,
1902                                    AVINDEX_KEYFRAME);
1903         }
1904     }
1905 }
1906 
matroska_parse_cues(MatroskaDemuxContext * matroska)1907 static void matroska_parse_cues(MatroskaDemuxContext *matroska) {
1908     int i;
1909 
1910     if (matroska->ctx->flags & AVFMT_FLAG_IGNIDX)
1911         return;
1912 
1913     for (i = 0; i < matroska->num_level1_elems; i++) {
1914         MatroskaLevel1Element *elem = &matroska->level1_elems[i];
1915         if (elem->id == MATROSKA_ID_CUES && !elem->parsed) {
1916             if (matroska_parse_seekhead_entry(matroska, elem->pos) < 0)
1917                 matroska->cues_parsing_deferred = -1;
1918             elem->parsed = 1;
1919             break;
1920         }
1921     }
1922 
1923     matroska_add_index_entries(matroska);
1924 }
1925 
matroska_aac_profile(char * codec_id)1926 static int matroska_aac_profile(char *codec_id)
1927 {
1928     static const char *const aac_profiles[] = { "MAIN", "LC", "SSR" };
1929     int profile;
1930 
1931     for (profile = 0; profile < FF_ARRAY_ELEMS(aac_profiles); profile++)
1932         if (strstr(codec_id, aac_profiles[profile]))
1933             break;
1934     return profile + 1;
1935 }
1936 
matroska_aac_sri(int samplerate)1937 static int matroska_aac_sri(int samplerate)
1938 {
1939     int sri;
1940 
1941     for (sri = 0; sri < FF_ARRAY_ELEMS(avpriv_mpeg4audio_sample_rates); sri++)
1942         if (avpriv_mpeg4audio_sample_rates[sri] == samplerate)
1943             break;
1944     return sri;
1945 }
1946 
matroska_metadata_creation_time(AVDictionary ** metadata,int64_t date_utc)1947 static void matroska_metadata_creation_time(AVDictionary **metadata, int64_t date_utc)
1948 {
1949     /* Convert to seconds and adjust by number of seconds between 2001-01-01 and Epoch */
1950     avpriv_dict_set_timestamp(metadata, "creation_time", date_utc / 1000 + 978307200000000LL);
1951 }
1952 
matroska_parse_flac(AVFormatContext * s,MatroskaTrack * track,int * offset)1953 static int matroska_parse_flac(AVFormatContext *s,
1954                                MatroskaTrack *track,
1955                                int *offset)
1956 {
1957     AVStream *st = track->stream;
1958     uint8_t *p = track->codec_priv.data;
1959     int size   = track->codec_priv.size;
1960 
1961     if (size < 8 + FLAC_STREAMINFO_SIZE || p[4] & 0x7f) {
1962         av_log(s, AV_LOG_WARNING, "Invalid FLAC private data\n");
1963         track->codec_priv.size = 0;
1964         return 0;
1965     }
1966     *offset = 8;
1967     track->codec_priv.size = 8 + FLAC_STREAMINFO_SIZE;
1968 
1969     p    += track->codec_priv.size;
1970     size -= track->codec_priv.size;
1971 
1972     /* parse the remaining metadata blocks if present */
1973     while (size >= 4) {
1974         int block_last, block_type, block_size;
1975 
1976         flac_parse_block_header(p, &block_last, &block_type, &block_size);
1977 
1978         p    += 4;
1979         size -= 4;
1980         if (block_size > size)
1981             return 0;
1982 
1983         /* check for the channel mask */
1984         if (block_type == FLAC_METADATA_TYPE_VORBIS_COMMENT) {
1985             AVDictionary *dict = NULL;
1986             AVDictionaryEntry *chmask;
1987 
1988             ff_vorbis_comment(s, &dict, p, block_size, 0);
1989             chmask = av_dict_get(dict, "WAVEFORMATEXTENSIBLE_CHANNEL_MASK", NULL, 0);
1990             if (chmask) {
1991                 uint64_t mask = strtol(chmask->value, NULL, 0);
1992                 if (!mask || mask & ~0x3ffffULL) {
1993                     av_log(s, AV_LOG_WARNING,
1994                            "Invalid value of WAVEFORMATEXTENSIBLE_CHANNEL_MASK\n");
1995                 } else
1996                     st->codecpar->channel_layout = mask;
1997             }
1998             av_dict_free(&dict);
1999         }
2000 
2001         p    += block_size;
2002         size -= block_size;
2003     }
2004 
2005     return 0;
2006 }
2007 
mkv_field_order(MatroskaDemuxContext * matroska,int64_t field_order)2008 static int mkv_field_order(MatroskaDemuxContext *matroska, int64_t field_order)
2009 {
2010     int major, minor, micro, bttb = 0;
2011 
2012     /* workaround a bug in our Matroska muxer, introduced in version 57.36 alongside
2013      * this function, and fixed in 57.52 */
2014     if (matroska->muxingapp && sscanf(matroska->muxingapp, "Lavf%d.%d.%d", &major, &minor, &micro) == 3)
2015         bttb = (major == 57 && minor >= 36 && minor <= 51 && micro >= 100);
2016 
2017     switch (field_order) {
2018     case MATROSKA_VIDEO_FIELDORDER_PROGRESSIVE:
2019         return AV_FIELD_PROGRESSIVE;
2020     case MATROSKA_VIDEO_FIELDORDER_UNDETERMINED:
2021         return AV_FIELD_UNKNOWN;
2022     case MATROSKA_VIDEO_FIELDORDER_TT:
2023         return AV_FIELD_TT;
2024     case MATROSKA_VIDEO_FIELDORDER_BB:
2025         return AV_FIELD_BB;
2026     case MATROSKA_VIDEO_FIELDORDER_BT:
2027         return bttb ? AV_FIELD_TB : AV_FIELD_BT;
2028     case MATROSKA_VIDEO_FIELDORDER_TB:
2029         return bttb ? AV_FIELD_BT : AV_FIELD_TB;
2030     default:
2031         return AV_FIELD_UNKNOWN;
2032     }
2033 }
2034 
mkv_stereo_mode_display_mul(int stereo_mode,int * h_width,int * h_height)2035 static void mkv_stereo_mode_display_mul(int stereo_mode,
2036                                         int *h_width, int *h_height)
2037 {
2038     switch (stereo_mode) {
2039         case MATROSKA_VIDEO_STEREOMODE_TYPE_MONO:
2040         case MATROSKA_VIDEO_STEREOMODE_TYPE_CHECKERBOARD_RL:
2041         case MATROSKA_VIDEO_STEREOMODE_TYPE_CHECKERBOARD_LR:
2042         case MATROSKA_VIDEO_STEREOMODE_TYPE_BOTH_EYES_BLOCK_RL:
2043         case MATROSKA_VIDEO_STEREOMODE_TYPE_BOTH_EYES_BLOCK_LR:
2044             break;
2045         case MATROSKA_VIDEO_STEREOMODE_TYPE_RIGHT_LEFT:
2046         case MATROSKA_VIDEO_STEREOMODE_TYPE_LEFT_RIGHT:
2047         case MATROSKA_VIDEO_STEREOMODE_TYPE_COL_INTERLEAVED_RL:
2048         case MATROSKA_VIDEO_STEREOMODE_TYPE_COL_INTERLEAVED_LR:
2049             *h_width = 2;
2050             break;
2051         case MATROSKA_VIDEO_STEREOMODE_TYPE_BOTTOM_TOP:
2052         case MATROSKA_VIDEO_STEREOMODE_TYPE_TOP_BOTTOM:
2053         case MATROSKA_VIDEO_STEREOMODE_TYPE_ROW_INTERLEAVED_RL:
2054         case MATROSKA_VIDEO_STEREOMODE_TYPE_ROW_INTERLEAVED_LR:
2055             *h_height = 2;
2056             break;
2057     }
2058 }
2059 
mkv_parse_video_color(AVStream * st,const MatroskaTrack * track)2060 static int mkv_parse_video_color(AVStream *st, const MatroskaTrack *track) {
2061     const MatroskaTrackVideoColor *color = track->video.color.elem;
2062     const MatroskaMasteringMeta *mastering_meta;
2063     int has_mastering_primaries, has_mastering_luminance;
2064 
2065     if (!track->video.color.nb_elem)
2066         return 0;
2067 
2068     mastering_meta = &color->mastering_meta;
2069     // Mastering primaries are CIE 1931 coords, and must be > 0.
2070     has_mastering_primaries =
2071         mastering_meta->r_x > 0 && mastering_meta->r_y > 0 &&
2072         mastering_meta->g_x > 0 && mastering_meta->g_y > 0 &&
2073         mastering_meta->b_x > 0 && mastering_meta->b_y > 0 &&
2074         mastering_meta->white_x > 0 && mastering_meta->white_y > 0;
2075     has_mastering_luminance = mastering_meta->max_luminance > 0;
2076 
2077     if (color->matrix_coefficients != AVCOL_SPC_RESERVED)
2078         st->codecpar->color_space = color->matrix_coefficients;
2079     if (color->primaries != AVCOL_PRI_RESERVED &&
2080         color->primaries != AVCOL_PRI_RESERVED0)
2081         st->codecpar->color_primaries = color->primaries;
2082     if (color->transfer_characteristics != AVCOL_TRC_RESERVED &&
2083         color->transfer_characteristics != AVCOL_TRC_RESERVED0)
2084         st->codecpar->color_trc = color->transfer_characteristics;
2085     if (color->range != AVCOL_RANGE_UNSPECIFIED &&
2086         color->range <= AVCOL_RANGE_JPEG)
2087         st->codecpar->color_range = color->range;
2088     if (color->chroma_siting_horz != MATROSKA_COLOUR_CHROMASITINGHORZ_UNDETERMINED &&
2089         color->chroma_siting_vert != MATROSKA_COLOUR_CHROMASITINGVERT_UNDETERMINED &&
2090         color->chroma_siting_horz  < MATROSKA_COLOUR_CHROMASITINGHORZ_NB &&
2091         color->chroma_siting_vert  < MATROSKA_COLOUR_CHROMASITINGVERT_NB) {
2092         st->codecpar->chroma_location =
2093             avcodec_chroma_pos_to_enum((color->chroma_siting_horz - 1) << 7,
2094                                        (color->chroma_siting_vert - 1) << 7);
2095     }
2096     if (color->max_cll && color->max_fall) {
2097         size_t size = 0;
2098         int ret;
2099         AVContentLightMetadata *metadata = av_content_light_metadata_alloc(&size);
2100         if (!metadata)
2101             return AVERROR(ENOMEM);
2102         ret = av_stream_add_side_data(st, AV_PKT_DATA_CONTENT_LIGHT_LEVEL,
2103                                       (uint8_t *)metadata, size);
2104         if (ret < 0) {
2105             av_freep(&metadata);
2106             return ret;
2107         }
2108         metadata->MaxCLL  = color->max_cll;
2109         metadata->MaxFALL = color->max_fall;
2110     }
2111 
2112     if (has_mastering_primaries || has_mastering_luminance) {
2113         AVMasteringDisplayMetadata *metadata =
2114             (AVMasteringDisplayMetadata*) av_stream_new_side_data(
2115                 st, AV_PKT_DATA_MASTERING_DISPLAY_METADATA,
2116                 sizeof(AVMasteringDisplayMetadata));
2117         if (!metadata) {
2118             return AVERROR(ENOMEM);
2119         }
2120         memset(metadata, 0, sizeof(AVMasteringDisplayMetadata));
2121         if (has_mastering_primaries) {
2122             metadata->display_primaries[0][0] = av_d2q(mastering_meta->r_x, INT_MAX);
2123             metadata->display_primaries[0][1] = av_d2q(mastering_meta->r_y, INT_MAX);
2124             metadata->display_primaries[1][0] = av_d2q(mastering_meta->g_x, INT_MAX);
2125             metadata->display_primaries[1][1] = av_d2q(mastering_meta->g_y, INT_MAX);
2126             metadata->display_primaries[2][0] = av_d2q(mastering_meta->b_x, INT_MAX);
2127             metadata->display_primaries[2][1] = av_d2q(mastering_meta->b_y, INT_MAX);
2128             metadata->white_point[0] = av_d2q(mastering_meta->white_x, INT_MAX);
2129             metadata->white_point[1] = av_d2q(mastering_meta->white_y, INT_MAX);
2130             metadata->has_primaries = 1;
2131         }
2132         if (has_mastering_luminance) {
2133             metadata->max_luminance = av_d2q(mastering_meta->max_luminance, INT_MAX);
2134             metadata->min_luminance = av_d2q(mastering_meta->min_luminance, INT_MAX);
2135             metadata->has_luminance = 1;
2136         }
2137     }
2138     return 0;
2139 }
2140 
mkv_parse_video_projection(AVStream * st,const MatroskaTrack * track)2141 static int mkv_parse_video_projection(AVStream *st, const MatroskaTrack *track) {
2142     AVSphericalMapping *spherical;
2143     enum AVSphericalProjection projection;
2144     size_t spherical_size;
2145     uint32_t l = 0, t = 0, r = 0, b = 0;
2146     uint32_t padding = 0;
2147     int ret;
2148     GetByteContext gb;
2149 
2150     bytestream2_init(&gb, track->video.projection.private.data,
2151                      track->video.projection.private.size);
2152 
2153     if (bytestream2_get_byte(&gb) != 0) {
2154         av_log(NULL, AV_LOG_WARNING, "Unknown spherical metadata\n");
2155         return 0;
2156     }
2157 
2158     bytestream2_skip(&gb, 3); // flags
2159 
2160     switch (track->video.projection.type) {
2161     case MATROSKA_VIDEO_PROJECTION_TYPE_EQUIRECTANGULAR:
2162         if (track->video.projection.private.size == 20) {
2163             t = bytestream2_get_be32(&gb);
2164             b = bytestream2_get_be32(&gb);
2165             l = bytestream2_get_be32(&gb);
2166             r = bytestream2_get_be32(&gb);
2167 
2168             if (b >= UINT_MAX - t || r >= UINT_MAX - l) {
2169                 av_log(NULL, AV_LOG_ERROR,
2170                        "Invalid bounding rectangle coordinates "
2171                        "%"PRIu32",%"PRIu32",%"PRIu32",%"PRIu32"\n",
2172                        l, t, r, b);
2173                 return AVERROR_INVALIDDATA;
2174             }
2175         } else if (track->video.projection.private.size != 0) {
2176             av_log(NULL, AV_LOG_ERROR, "Unknown spherical metadata\n");
2177             return AVERROR_INVALIDDATA;
2178         }
2179 
2180         if (l || t || r || b)
2181             projection = AV_SPHERICAL_EQUIRECTANGULAR_TILE;
2182         else
2183             projection = AV_SPHERICAL_EQUIRECTANGULAR;
2184         break;
2185     case MATROSKA_VIDEO_PROJECTION_TYPE_CUBEMAP:
2186         if (track->video.projection.private.size < 4) {
2187             av_log(NULL, AV_LOG_ERROR, "Missing projection private properties\n");
2188             return AVERROR_INVALIDDATA;
2189         } else if (track->video.projection.private.size == 12) {
2190             uint32_t layout = bytestream2_get_be32(&gb);
2191             if (layout) {
2192                 av_log(NULL, AV_LOG_WARNING,
2193                        "Unknown spherical cubemap layout %"PRIu32"\n", layout);
2194                 return 0;
2195             }
2196             projection = AV_SPHERICAL_CUBEMAP;
2197             padding = bytestream2_get_be32(&gb);
2198         } else {
2199             av_log(NULL, AV_LOG_ERROR, "Unknown spherical metadata\n");
2200             return AVERROR_INVALIDDATA;
2201         }
2202         break;
2203     case MATROSKA_VIDEO_PROJECTION_TYPE_RECTANGULAR:
2204         /* No Spherical metadata */
2205         return 0;
2206     default:
2207         av_log(NULL, AV_LOG_WARNING,
2208                "Unknown spherical metadata type %"PRIu64"\n",
2209                track->video.projection.type);
2210         return 0;
2211     }
2212 
2213     spherical = av_spherical_alloc(&spherical_size);
2214     if (!spherical)
2215         return AVERROR(ENOMEM);
2216 
2217     spherical->projection = projection;
2218 
2219     spherical->yaw   = (int32_t) (track->video.projection.yaw   * (1 << 16));
2220     spherical->pitch = (int32_t) (track->video.projection.pitch * (1 << 16));
2221     spherical->roll  = (int32_t) (track->video.projection.roll  * (1 << 16));
2222 
2223     spherical->padding = padding;
2224 
2225     spherical->bound_left   = l;
2226     spherical->bound_top    = t;
2227     spherical->bound_right  = r;
2228     spherical->bound_bottom = b;
2229 
2230     ret = av_stream_add_side_data(st, AV_PKT_DATA_SPHERICAL, (uint8_t *)spherical,
2231                                   spherical_size);
2232     if (ret < 0) {
2233         av_freep(&spherical);
2234         return ret;
2235     }
2236 
2237     return 0;
2238 }
2239 
get_qt_codec(MatroskaTrack * track,uint32_t * fourcc,enum AVCodecID * codec_id)2240 static int get_qt_codec(MatroskaTrack *track, uint32_t *fourcc, enum AVCodecID *codec_id)
2241 {
2242     const AVCodecTag *codec_tags;
2243 
2244     codec_tags = track->type == MATROSKA_TRACK_TYPE_VIDEO ?
2245             ff_codec_movvideo_tags : ff_codec_movaudio_tags;
2246 
2247     /* Normalize noncompliant private data that starts with the fourcc
2248      * by expanding/shifting the data by 4 bytes and storing the data
2249      * size at the start. */
2250     if (ff_codec_get_id(codec_tags, AV_RL32(track->codec_priv.data))) {
2251         int ret = av_buffer_realloc(&track->codec_priv.buf,
2252                                     track->codec_priv.size + 4 + AV_INPUT_BUFFER_PADDING_SIZE);
2253         if (ret < 0)
2254             return ret;
2255 
2256         track->codec_priv.data = track->codec_priv.buf->data;
2257         memmove(track->codec_priv.data + 4, track->codec_priv.data, track->codec_priv.size);
2258         track->codec_priv.size += 4;
2259         AV_WB32(track->codec_priv.data, track->codec_priv.size);
2260     }
2261 
2262     *fourcc = AV_RL32(track->codec_priv.data + 4);
2263     *codec_id = ff_codec_get_id(codec_tags, *fourcc);
2264 
2265     return 0;
2266 }
2267 
matroska_parse_tracks(AVFormatContext * s)2268 static int matroska_parse_tracks(AVFormatContext *s)
2269 {
2270     MatroskaDemuxContext *matroska = s->priv_data;
2271     MatroskaTrack *tracks = matroska->tracks.elem;
2272     AVStream *st;
2273     int i, j, ret;
2274     int k;
2275 
2276     for (i = 0; i < matroska->tracks.nb_elem; i++) {
2277         MatroskaTrack *track = &tracks[i];
2278         enum AVCodecID codec_id = AV_CODEC_ID_NONE;
2279         EbmlList *encodings_list = &track->encodings;
2280         MatroskaTrackEncoding *encodings = encodings_list->elem;
2281         uint8_t *extradata = NULL;
2282         int extradata_size = 0;
2283         int extradata_offset = 0;
2284         uint32_t fourcc = 0;
2285         AVIOContext b;
2286         char* key_id_base64 = NULL;
2287         int bit_depth = -1;
2288 
2289         /* Apply some sanity checks. */
2290         if (track->type != MATROSKA_TRACK_TYPE_VIDEO &&
2291             track->type != MATROSKA_TRACK_TYPE_AUDIO &&
2292             track->type != MATROSKA_TRACK_TYPE_SUBTITLE &&
2293             track->type != MATROSKA_TRACK_TYPE_METADATA) {
2294             av_log(matroska->ctx, AV_LOG_INFO,
2295                    "Unknown or unsupported track type %"PRIu64"\n",
2296                    track->type);
2297             continue;
2298         }
2299         if (!track->codec_id)
2300             continue;
2301 
2302         if (track->audio.samplerate < 0 || track->audio.samplerate > INT_MAX ||
2303             isnan(track->audio.samplerate)) {
2304             av_log(matroska->ctx, AV_LOG_WARNING,
2305                    "Invalid sample rate %f, defaulting to 8000 instead.\n",
2306                    track->audio.samplerate);
2307             track->audio.samplerate = 8000;
2308         }
2309 
2310         if (track->type == MATROSKA_TRACK_TYPE_VIDEO) {
2311             if (!track->default_duration && track->video.frame_rate > 0) {
2312                 double default_duration = 1000000000 / track->video.frame_rate;
2313                 if (default_duration > UINT64_MAX || default_duration < 0) {
2314                     av_log(matroska->ctx, AV_LOG_WARNING,
2315                          "Invalid frame rate %e. Cannot calculate default duration.\n",
2316                          track->video.frame_rate);
2317                 } else {
2318                     track->default_duration = default_duration;
2319                 }
2320             }
2321             if (track->video.display_width == -1)
2322                 track->video.display_width = track->video.pixel_width;
2323             if (track->video.display_height == -1)
2324                 track->video.display_height = track->video.pixel_height;
2325             if (track->video.color_space.size == 4)
2326                 fourcc = AV_RL32(track->video.color_space.data);
2327         } else if (track->type == MATROSKA_TRACK_TYPE_AUDIO) {
2328             if (!track->audio.out_samplerate)
2329                 track->audio.out_samplerate = track->audio.samplerate;
2330         }
2331         if (encodings_list->nb_elem > 1) {
2332             av_log(matroska->ctx, AV_LOG_ERROR,
2333                    "Multiple combined encodings not supported");
2334         } else if (encodings_list->nb_elem == 1) {
2335             if (encodings[0].type) {
2336                 if (encodings[0].encryption.key_id.size > 0) {
2337                     /* Save the encryption key id to be stored later as a
2338                        metadata tag. */
2339                     const int b64_size = AV_BASE64_SIZE(encodings[0].encryption.key_id.size);
2340                     key_id_base64 = av_malloc(b64_size);
2341                     if (key_id_base64 == NULL)
2342                         return AVERROR(ENOMEM);
2343 
2344                     av_base64_encode(key_id_base64, b64_size,
2345                                      encodings[0].encryption.key_id.data,
2346                                      encodings[0].encryption.key_id.size);
2347                 } else {
2348                     encodings[0].scope = 0;
2349                     av_log(matroska->ctx, AV_LOG_ERROR,
2350                            "Unsupported encoding type");
2351                 }
2352             } else if (
2353 #if CONFIG_ZLIB
2354                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_ZLIB  &&
2355 #endif
2356 #if CONFIG_BZLIB
2357                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_BZLIB &&
2358 #endif
2359 #if CONFIG_LZO
2360                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_LZO   &&
2361 #endif
2362                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_HEADERSTRIP) {
2363                 encodings[0].scope = 0;
2364                 av_log(matroska->ctx, AV_LOG_ERROR,
2365                        "Unsupported encoding type");
2366             } else if (track->codec_priv.size && encodings[0].scope & 2) {
2367                 uint8_t *codec_priv = track->codec_priv.data;
2368                 int ret = matroska_decode_buffer(&track->codec_priv.data,
2369                                                  &track->codec_priv.size,
2370                                                  track);
2371                 if (ret < 0) {
2372                     track->codec_priv.data = NULL;
2373                     track->codec_priv.size = 0;
2374                     av_log(matroska->ctx, AV_LOG_ERROR,
2375                            "Failed to decode codec private data\n");
2376                 }
2377 
2378                 if (codec_priv != track->codec_priv.data) {
2379                     av_buffer_unref(&track->codec_priv.buf);
2380                     if (track->codec_priv.data) {
2381                         track->codec_priv.buf = av_buffer_create(track->codec_priv.data,
2382                                                                  track->codec_priv.size + AV_INPUT_BUFFER_PADDING_SIZE,
2383                                                                  NULL, NULL, 0);
2384                         if (!track->codec_priv.buf) {
2385                             av_freep(&track->codec_priv.data);
2386                             track->codec_priv.size = 0;
2387                             return AVERROR(ENOMEM);
2388                         }
2389                     }
2390                 }
2391             }
2392         }
2393 
2394         for (j = 0; ff_mkv_codec_tags[j].id != AV_CODEC_ID_NONE; j++) {
2395             if (!strncmp(ff_mkv_codec_tags[j].str, track->codec_id,
2396                          strlen(ff_mkv_codec_tags[j].str))) {
2397                 codec_id = ff_mkv_codec_tags[j].id;
2398                 break;
2399             }
2400         }
2401 
2402         st = track->stream = avformat_new_stream(s, NULL);
2403         if (!st) {
2404             av_free(key_id_base64);
2405             return AVERROR(ENOMEM);
2406         }
2407 
2408         if (key_id_base64) {
2409             /* export encryption key id as base64 metadata tag */
2410             av_dict_set(&st->metadata, "enc_key_id", key_id_base64,
2411                         AV_DICT_DONT_STRDUP_VAL);
2412         }
2413 
2414         if (!strcmp(track->codec_id, "V_MS/VFW/FOURCC") &&
2415              track->codec_priv.size >= 40               &&
2416             track->codec_priv.data) {
2417             track->ms_compat    = 1;
2418             bit_depth           = AV_RL16(track->codec_priv.data + 14);
2419             fourcc              = AV_RL32(track->codec_priv.data + 16);
2420             codec_id            = ff_codec_get_id(ff_codec_bmp_tags,
2421                                                   fourcc);
2422             if (!codec_id)
2423                 codec_id        = ff_codec_get_id(ff_codec_movvideo_tags,
2424                                                   fourcc);
2425             extradata_offset    = 40;
2426         } else if (!strcmp(track->codec_id, "A_MS/ACM") &&
2427                    track->codec_priv.size >= 14         &&
2428                    track->codec_priv.data) {
2429             int ret;
2430             ffio_init_context(&b, track->codec_priv.data,
2431                               track->codec_priv.size,
2432                               0, NULL, NULL, NULL, NULL);
2433             ret = ff_get_wav_header(s, &b, st->codecpar, track->codec_priv.size, 0);
2434             if (ret < 0)
2435                 return ret;
2436             codec_id         = st->codecpar->codec_id;
2437             fourcc           = st->codecpar->codec_tag;
2438             extradata_offset = FFMIN(track->codec_priv.size, 18);
2439         } else if (!strcmp(track->codec_id, "A_QUICKTIME")
2440                    /* Normally 36, but allow noncompliant private data */
2441                    && (track->codec_priv.size >= 32)
2442                    && (track->codec_priv.data)) {
2443             uint16_t sample_size;
2444             int ret = get_qt_codec(track, &fourcc, &codec_id);
2445             if (ret < 0)
2446                 return ret;
2447             sample_size = AV_RB16(track->codec_priv.data + 26);
2448             if (fourcc == 0) {
2449                 if (sample_size == 8) {
2450                     fourcc = MKTAG('r','a','w',' ');
2451                     codec_id = ff_codec_get_id(ff_codec_movaudio_tags, fourcc);
2452                 } else if (sample_size == 16) {
2453                     fourcc = MKTAG('t','w','o','s');
2454                     codec_id = ff_codec_get_id(ff_codec_movaudio_tags, fourcc);
2455                 }
2456             }
2457             if ((fourcc == MKTAG('t','w','o','s') ||
2458                     fourcc == MKTAG('s','o','w','t')) &&
2459                     sample_size == 8)
2460                 codec_id = AV_CODEC_ID_PCM_S8;
2461         } else if (!strcmp(track->codec_id, "V_QUICKTIME") &&
2462                    (track->codec_priv.size >= 21)          &&
2463                    (track->codec_priv.data)) {
2464             int ret = get_qt_codec(track, &fourcc, &codec_id);
2465             if (ret < 0)
2466                 return ret;
2467             if (codec_id == AV_CODEC_ID_NONE && AV_RL32(track->codec_priv.data+4) == AV_RL32("SMI ")) {
2468                 fourcc = MKTAG('S','V','Q','3');
2469                 codec_id = ff_codec_get_id(ff_codec_movvideo_tags, fourcc);
2470             }
2471             if (codec_id == AV_CODEC_ID_NONE)
2472                 av_log(matroska->ctx, AV_LOG_ERROR,
2473                        "mov FourCC not found %s.\n", av_fourcc2str(fourcc));
2474             if (track->codec_priv.size >= 86) {
2475                 bit_depth = AV_RB16(track->codec_priv.data + 82);
2476                 ffio_init_context(&b, track->codec_priv.data,
2477                                   track->codec_priv.size,
2478                                   0, NULL, NULL, NULL, NULL);
2479                 if (ff_get_qtpalette(codec_id, &b, track->palette)) {
2480                     bit_depth &= 0x1F;
2481                     track->has_palette = 1;
2482                 }
2483             }
2484         } else if (codec_id == AV_CODEC_ID_PCM_S16BE) {
2485             switch (track->audio.bitdepth) {
2486             case  8:
2487                 codec_id = AV_CODEC_ID_PCM_U8;
2488                 break;
2489             case 24:
2490                 codec_id = AV_CODEC_ID_PCM_S24BE;
2491                 break;
2492             case 32:
2493                 codec_id = AV_CODEC_ID_PCM_S32BE;
2494                 break;
2495             }
2496         } else if (codec_id == AV_CODEC_ID_PCM_S16LE) {
2497             switch (track->audio.bitdepth) {
2498             case  8:
2499                 codec_id = AV_CODEC_ID_PCM_U8;
2500                 break;
2501             case 24:
2502                 codec_id = AV_CODEC_ID_PCM_S24LE;
2503                 break;
2504             case 32:
2505                 codec_id = AV_CODEC_ID_PCM_S32LE;
2506                 break;
2507             }
2508         } else if (codec_id == AV_CODEC_ID_PCM_F32LE &&
2509                    track->audio.bitdepth == 64) {
2510             codec_id = AV_CODEC_ID_PCM_F64LE;
2511         } else if (codec_id == AV_CODEC_ID_AAC && !track->codec_priv.size) {
2512             int profile = matroska_aac_profile(track->codec_id);
2513             int sri     = matroska_aac_sri(track->audio.samplerate);
2514             extradata   = av_mallocz(5 + AV_INPUT_BUFFER_PADDING_SIZE);
2515             if (!extradata)
2516                 return AVERROR(ENOMEM);
2517             extradata[0] = (profile << 3) | ((sri & 0x0E) >> 1);
2518             extradata[1] = ((sri & 0x01) << 7) | (track->audio.channels << 3);
2519             if (strstr(track->codec_id, "SBR")) {
2520                 sri            = matroska_aac_sri(track->audio.out_samplerate);
2521                 extradata[2]   = 0x56;
2522                 extradata[3]   = 0xE5;
2523                 extradata[4]   = 0x80 | (sri << 3);
2524                 extradata_size = 5;
2525             } else
2526                 extradata_size = 2;
2527         } else if (codec_id == AV_CODEC_ID_ALAC && track->codec_priv.size && track->codec_priv.size < INT_MAX - 12 - AV_INPUT_BUFFER_PADDING_SIZE) {
2528             /* Only ALAC's magic cookie is stored in Matroska's track headers.
2529              * Create the "atom size", "tag", and "tag version" fields the
2530              * decoder expects manually. */
2531             extradata_size = 12 + track->codec_priv.size;
2532             extradata      = av_mallocz(extradata_size +
2533                                         AV_INPUT_BUFFER_PADDING_SIZE);
2534             if (!extradata)
2535                 return AVERROR(ENOMEM);
2536             AV_WB32(extradata, extradata_size);
2537             memcpy(&extradata[4], "alac", 4);
2538             AV_WB32(&extradata[8], 0);
2539             memcpy(&extradata[12], track->codec_priv.data,
2540                    track->codec_priv.size);
2541         } else if (codec_id == AV_CODEC_ID_TTA) {
2542             uint8_t *ptr;
2543             if (track->audio.channels > UINT16_MAX ||
2544                 track->audio.bitdepth > UINT16_MAX) {
2545                 av_log(matroska->ctx, AV_LOG_WARNING,
2546                        "Too large audio channel number %"PRIu64
2547                        " or bitdepth %"PRIu64". Skipping track.\n",
2548                        track->audio.channels, track->audio.bitdepth);
2549                 if (matroska->ctx->error_recognition & AV_EF_EXPLODE)
2550                     return AVERROR_INVALIDDATA;
2551                 else
2552                     continue;
2553             }
2554             if (track->audio.out_samplerate < 0 || track->audio.out_samplerate > INT_MAX)
2555                 return AVERROR_INVALIDDATA;
2556             extradata_size = 22;
2557             extradata      = av_mallocz(extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);
2558             if (!extradata)
2559                 return AVERROR(ENOMEM);
2560             ptr = extradata;
2561             bytestream_put_be32(&ptr, AV_RB32("TTA1"));
2562             bytestream_put_le16(&ptr, 1);
2563             bytestream_put_le16(&ptr, track->audio.channels);
2564             bytestream_put_le16(&ptr, track->audio.bitdepth);
2565             bytestream_put_le32(&ptr, track->audio.out_samplerate);
2566             bytestream_put_le32(&ptr, av_rescale(matroska->duration * matroska->time_scale,
2567                                                  track->audio.out_samplerate,
2568                                                  AV_TIME_BASE * 1000));
2569         } else if (codec_id == AV_CODEC_ID_RV10 ||
2570                    codec_id == AV_CODEC_ID_RV20 ||
2571                    codec_id == AV_CODEC_ID_RV30 ||
2572                    codec_id == AV_CODEC_ID_RV40) {
2573             extradata_offset = 26;
2574         } else if (codec_id == AV_CODEC_ID_RA_144) {
2575             track->audio.out_samplerate = 8000;
2576             track->audio.channels       = 1;
2577         } else if ((codec_id == AV_CODEC_ID_RA_288 ||
2578                     codec_id == AV_CODEC_ID_COOK   ||
2579                     codec_id == AV_CODEC_ID_ATRAC3 ||
2580                     codec_id == AV_CODEC_ID_SIPR)
2581                       && track->codec_priv.data) {
2582 #if CONFIG_RA_288_DECODER || CONFIG_COOK_DECODER || CONFIG_ATRAC3_DECODER || CONFIG_SIPR_DECODER
2583             int flavor;
2584 
2585             ffio_init_context(&b, track->codec_priv.data,
2586                               track->codec_priv.size,
2587                               0, NULL, NULL, NULL, NULL);
2588             avio_skip(&b, 22);
2589             flavor                       = avio_rb16(&b);
2590             track->audio.coded_framesize = avio_rb32(&b);
2591             avio_skip(&b, 12);
2592             track->audio.sub_packet_h    = avio_rb16(&b);
2593             track->audio.frame_size      = avio_rb16(&b);
2594             track->audio.sub_packet_size = avio_rb16(&b);
2595             if (flavor                        < 0 ||
2596                 track->audio.coded_framesize <= 0 ||
2597                 track->audio.sub_packet_h    <= 0 ||
2598                 track->audio.frame_size      <= 0 ||
2599                 track->audio.sub_packet_size <= 0 && codec_id != AV_CODEC_ID_SIPR)
2600                 return AVERROR_INVALIDDATA;
2601             track->audio.buf = av_malloc_array(track->audio.sub_packet_h,
2602                                                track->audio.frame_size);
2603             if (!track->audio.buf)
2604                 return AVERROR(ENOMEM);
2605             if (codec_id == AV_CODEC_ID_RA_288) {
2606                 st->codecpar->block_align = track->audio.coded_framesize;
2607                 track->codec_priv.size = 0;
2608             } else {
2609                 if (codec_id == AV_CODEC_ID_SIPR && flavor < 4) {
2610                     static const int sipr_bit_rate[4] = { 6504, 8496, 5000, 16000 };
2611                     track->audio.sub_packet_size = ff_sipr_subpk_size[flavor];
2612                     st->codecpar->bit_rate          = sipr_bit_rate[flavor];
2613                 }
2614                 st->codecpar->block_align = track->audio.sub_packet_size;
2615                 extradata_offset       = 78;
2616             }
2617 #else
2618             return AVERROR_INVALIDDATA;
2619 #endif
2620         } else if (codec_id == AV_CODEC_ID_FLAC && track->codec_priv.size) {
2621             ret = matroska_parse_flac(s, track, &extradata_offset);
2622             if (ret < 0)
2623                 return ret;
2624         } else if (codec_id == AV_CODEC_ID_PRORES && track->codec_priv.size == 4) {
2625             fourcc = AV_RL32(track->codec_priv.data);
2626         } else if (codec_id == AV_CODEC_ID_VP9 && track->codec_priv.size) {
2627             /* we don't need any value stored in CodecPrivate.
2628                make sure that it's not exported as extradata. */
2629             track->codec_priv.size = 0;
2630         } else if (codec_id == AV_CODEC_ID_AV1 && track->codec_priv.size) {
2631             /* For now, propagate only the OBUs, if any. Once libavcodec is
2632                updated to handle isobmff style extradata this can be removed. */
2633             extradata_offset = 4;
2634         }
2635         track->codec_priv.size -= extradata_offset;
2636 
2637         if (codec_id == AV_CODEC_ID_NONE)
2638             av_log(matroska->ctx, AV_LOG_INFO,
2639                    "Unknown/unsupported AVCodecID %s.\n", track->codec_id);
2640 
2641         if (track->time_scale < 0.01)
2642             track->time_scale = 1.0;
2643         avpriv_set_pts_info(st, 64, matroska->time_scale * track->time_scale,
2644                             1000 * 1000 * 1000);    /* 64 bit pts in ns */
2645 
2646         /* convert the delay from ns to the track timebase */
2647         track->codec_delay_in_track_tb = av_rescale_q(track->codec_delay,
2648                                           (AVRational){ 1, 1000000000 },
2649                                           st->time_base);
2650 
2651         st->codecpar->codec_id = codec_id;
2652 
2653         if (strcmp(track->language, "und"))
2654             av_dict_set(&st->metadata, "language", track->language, 0);
2655         av_dict_set(&st->metadata, "title", track->name, 0);
2656 
2657         if (track->flag_default)
2658             st->disposition |= AV_DISPOSITION_DEFAULT;
2659         if (track->flag_forced)
2660             st->disposition |= AV_DISPOSITION_FORCED;
2661 
2662         if (!st->codecpar->extradata) {
2663             if (extradata) {
2664                 st->codecpar->extradata      = extradata;
2665                 st->codecpar->extradata_size = extradata_size;
2666             } else if (track->codec_priv.data && track->codec_priv.size > 0) {
2667                 if (ff_alloc_extradata(st->codecpar, track->codec_priv.size))
2668                     return AVERROR(ENOMEM);
2669                 memcpy(st->codecpar->extradata,
2670                        track->codec_priv.data + extradata_offset,
2671                        track->codec_priv.size);
2672             }
2673         }
2674 
2675         if (track->type == MATROSKA_TRACK_TYPE_VIDEO) {
2676             MatroskaTrackPlane *planes = track->operation.combine_planes.elem;
2677             int display_width_mul  = 1;
2678             int display_height_mul = 1;
2679 
2680             st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
2681             st->codecpar->codec_tag  = fourcc;
2682             if (bit_depth >= 0)
2683                 st->codecpar->bits_per_coded_sample = bit_depth;
2684             st->codecpar->width      = track->video.pixel_width;
2685             st->codecpar->height     = track->video.pixel_height;
2686 
2687             if (track->video.interlaced == MATROSKA_VIDEO_INTERLACE_FLAG_INTERLACED)
2688                 st->codecpar->field_order = mkv_field_order(matroska, track->video.field_order);
2689             else if (track->video.interlaced == MATROSKA_VIDEO_INTERLACE_FLAG_PROGRESSIVE)
2690                 st->codecpar->field_order = AV_FIELD_PROGRESSIVE;
2691 
2692             if (track->video.stereo_mode && track->video.stereo_mode < MATROSKA_VIDEO_STEREOMODE_TYPE_NB)
2693                 mkv_stereo_mode_display_mul(track->video.stereo_mode, &display_width_mul, &display_height_mul);
2694 
2695             if (track->video.display_unit < MATROSKA_VIDEO_DISPLAYUNIT_UNKNOWN) {
2696                 av_reduce(&st->sample_aspect_ratio.num,
2697                           &st->sample_aspect_ratio.den,
2698                           st->codecpar->height * track->video.display_width  * display_width_mul,
2699                           st->codecpar->width  * track->video.display_height * display_height_mul,
2700                           255);
2701             }
2702             if (st->codecpar->codec_id != AV_CODEC_ID_HEVC)
2703                 st->need_parsing = AVSTREAM_PARSE_HEADERS;
2704 
2705             if (track->default_duration) {
2706                 av_reduce(&st->avg_frame_rate.num, &st->avg_frame_rate.den,
2707                           1000000000, track->default_duration, 30000);
2708 #if FF_API_R_FRAME_RATE
2709                 if (   st->avg_frame_rate.num < st->avg_frame_rate.den * 1000LL
2710                     && st->avg_frame_rate.num > st->avg_frame_rate.den * 5LL)
2711                     st->r_frame_rate = st->avg_frame_rate;
2712 #endif
2713             }
2714 
2715             /* export stereo mode flag as metadata tag */
2716             if (track->video.stereo_mode && track->video.stereo_mode < MATROSKA_VIDEO_STEREOMODE_TYPE_NB)
2717                 av_dict_set(&st->metadata, "stereo_mode", ff_matroska_video_stereo_mode[track->video.stereo_mode], 0);
2718 
2719             /* export alpha mode flag as metadata tag  */
2720             if (track->video.alpha_mode)
2721                 av_dict_set(&st->metadata, "alpha_mode", "1", 0);
2722 
2723             /* if we have virtual track, mark the real tracks */
2724             for (j=0; j < track->operation.combine_planes.nb_elem; j++) {
2725                 char buf[32];
2726                 if (planes[j].type >= MATROSKA_VIDEO_STEREO_PLANE_COUNT)
2727                     continue;
2728                 snprintf(buf, sizeof(buf), "%s_%d",
2729                          ff_matroska_video_stereo_plane[planes[j].type], i);
2730                 for (k=0; k < matroska->tracks.nb_elem; k++)
2731                     if (planes[j].uid == tracks[k].uid && tracks[k].stream) {
2732                         av_dict_set(&tracks[k].stream->metadata,
2733                                     "stereo_mode", buf, 0);
2734                         break;
2735                     }
2736             }
2737             // add stream level stereo3d side data if it is a supported format
2738             if (track->video.stereo_mode < MATROSKA_VIDEO_STEREOMODE_TYPE_NB &&
2739                 track->video.stereo_mode != 10 && track->video.stereo_mode != 12) {
2740                 int ret = ff_mkv_stereo3d_conv(st, track->video.stereo_mode);
2741                 if (ret < 0)
2742                     return ret;
2743             }
2744 
2745             ret = mkv_parse_video_color(st, track);
2746             if (ret < 0)
2747                 return ret;
2748             ret = mkv_parse_video_projection(st, track);
2749             if (ret < 0)
2750                 return ret;
2751         } else if (track->type == MATROSKA_TRACK_TYPE_AUDIO) {
2752             st->codecpar->codec_type  = AVMEDIA_TYPE_AUDIO;
2753             st->codecpar->codec_tag   = fourcc;
2754             st->codecpar->sample_rate = track->audio.out_samplerate;
2755             st->codecpar->channels    = track->audio.channels;
2756             if (!st->codecpar->bits_per_coded_sample)
2757                 st->codecpar->bits_per_coded_sample = track->audio.bitdepth;
2758             if (st->codecpar->codec_id == AV_CODEC_ID_MP3 ||
2759                 st->codecpar->codec_id == AV_CODEC_ID_MLP ||
2760                 st->codecpar->codec_id == AV_CODEC_ID_TRUEHD)
2761                 st->need_parsing = AVSTREAM_PARSE_FULL;
2762             else if (st->codecpar->codec_id != AV_CODEC_ID_AAC)
2763                 st->need_parsing = AVSTREAM_PARSE_HEADERS;
2764             if (track->codec_delay > 0) {
2765                 st->codecpar->initial_padding = av_rescale_q(track->codec_delay,
2766                                                              (AVRational){1, 1000000000},
2767                                                              (AVRational){1, st->codecpar->codec_id == AV_CODEC_ID_OPUS ?
2768                                                                              48000 : st->codecpar->sample_rate});
2769             }
2770             if (track->seek_preroll > 0) {
2771                 st->codecpar->seek_preroll = av_rescale_q(track->seek_preroll,
2772                                                           (AVRational){1, 1000000000},
2773                                                           (AVRational){1, st->codecpar->sample_rate});
2774             }
2775         } else if (codec_id == AV_CODEC_ID_WEBVTT) {
2776             st->codecpar->codec_type = AVMEDIA_TYPE_SUBTITLE;
2777 
2778             if (!strcmp(track->codec_id, "D_WEBVTT/CAPTIONS")) {
2779                 st->disposition |= AV_DISPOSITION_CAPTIONS;
2780             } else if (!strcmp(track->codec_id, "D_WEBVTT/DESCRIPTIONS")) {
2781                 st->disposition |= AV_DISPOSITION_DESCRIPTIONS;
2782             } else if (!strcmp(track->codec_id, "D_WEBVTT/METADATA")) {
2783                 st->disposition |= AV_DISPOSITION_METADATA;
2784             }
2785         } else if (track->type == MATROSKA_TRACK_TYPE_SUBTITLE) {
2786             st->codecpar->codec_type = AVMEDIA_TYPE_SUBTITLE;
2787         }
2788     }
2789 
2790     return 0;
2791 }
2792 
matroska_read_header(AVFormatContext * s)2793 static int matroska_read_header(AVFormatContext *s)
2794 {
2795     MatroskaDemuxContext *matroska = s->priv_data;
2796     EbmlList *attachments_list = &matroska->attachments;
2797     EbmlList *chapters_list    = &matroska->chapters;
2798     MatroskaAttachment *attachments;
2799     MatroskaChapter *chapters;
2800     uint64_t max_start = 0;
2801     int64_t pos;
2802     Ebml ebml = { 0 };
2803     int i, j, res;
2804 
2805     matroska->ctx = s;
2806     matroska->cues_parsing_deferred = 1;
2807 
2808     /* First read the EBML header. */
2809     if (ebml_parse(matroska, ebml_syntax, &ebml) || !ebml.doctype) {
2810         av_log(matroska->ctx, AV_LOG_ERROR, "EBML header parsing failed\n");
2811         ebml_free(ebml_syntax, &ebml);
2812         return AVERROR_INVALIDDATA;
2813     }
2814     if (ebml.version         > EBML_VERSION      ||
2815         ebml.max_size        > sizeof(uint64_t)  ||
2816         ebml.id_length       > sizeof(uint32_t)  ||
2817         ebml.doctype_version > 3) {
2818         avpriv_report_missing_feature(matroska->ctx,
2819                                       "EBML version %"PRIu64", doctype %s, doc version %"PRIu64,
2820                                       ebml.version, ebml.doctype, ebml.doctype_version);
2821         ebml_free(ebml_syntax, &ebml);
2822         return AVERROR_PATCHWELCOME;
2823     } else if (ebml.doctype_version == 3) {
2824         av_log(matroska->ctx, AV_LOG_WARNING,
2825                "EBML header using unsupported features\n"
2826                "(EBML version %"PRIu64", doctype %s, doc version %"PRIu64")\n",
2827                ebml.version, ebml.doctype, ebml.doctype_version);
2828     }
2829     for (i = 0; i < FF_ARRAY_ELEMS(matroska_doctypes); i++)
2830         if (!strcmp(ebml.doctype, matroska_doctypes[i]))
2831             break;
2832     if (i >= FF_ARRAY_ELEMS(matroska_doctypes)) {
2833         av_log(s, AV_LOG_WARNING, "Unknown EBML doctype '%s'\n", ebml.doctype);
2834         if (matroska->ctx->error_recognition & AV_EF_EXPLODE) {
2835             ebml_free(ebml_syntax, &ebml);
2836             return AVERROR_INVALIDDATA;
2837         }
2838     }
2839     ebml_free(ebml_syntax, &ebml);
2840 
2841     /* The next thing is a segment. */
2842     pos = avio_tell(matroska->ctx->pb);
2843     res = ebml_parse(matroska, matroska_segments, matroska);
2844     // Try resyncing until we find an EBML_STOP type element.
2845     while (res != 1) {
2846         res = matroska_resync(matroska, pos);
2847         if (res < 0)
2848             goto fail;
2849         pos = avio_tell(matroska->ctx->pb);
2850         res = ebml_parse(matroska, matroska_segment, matroska);
2851     }
2852     /* Set data_offset as it might be needed later by seek_frame_generic. */
2853     if (matroska->current_id == MATROSKA_ID_CLUSTER)
2854         s->internal->data_offset = avio_tell(matroska->ctx->pb) - 4;
2855     matroska_execute_seekhead(matroska);
2856 
2857     if (!matroska->time_scale)
2858         matroska->time_scale = 1000000;
2859     if (matroska->duration)
2860         matroska->ctx->duration = matroska->duration * matroska->time_scale *
2861                                   1000 / AV_TIME_BASE;
2862     av_dict_set(&s->metadata, "title", matroska->title, 0);
2863     av_dict_set(&s->metadata, "encoder", matroska->muxingapp, 0);
2864 
2865     if (matroska->date_utc.size == 8)
2866         matroska_metadata_creation_time(&s->metadata, AV_RB64(matroska->date_utc.data));
2867 
2868     res = matroska_parse_tracks(s);
2869     if (res < 0)
2870         goto fail;
2871 
2872     attachments = attachments_list->elem;
2873     for (j = 0; j < attachments_list->nb_elem; j++) {
2874         if (!(attachments[j].filename && attachments[j].mime &&
2875               attachments[j].bin.data && attachments[j].bin.size > 0)) {
2876             av_log(matroska->ctx, AV_LOG_ERROR, "incomplete attachment\n");
2877         } else {
2878             AVStream *st = avformat_new_stream(s, NULL);
2879             if (!st)
2880                 break;
2881             av_dict_set(&st->metadata, "filename", attachments[j].filename, 0);
2882             av_dict_set(&st->metadata, "mimetype", attachments[j].mime, 0);
2883             st->codecpar->codec_id   = AV_CODEC_ID_NONE;
2884 
2885             for (i = 0; ff_mkv_image_mime_tags[i].id != AV_CODEC_ID_NONE; i++) {
2886                 if (!strncmp(ff_mkv_image_mime_tags[i].str, attachments[j].mime,
2887                              strlen(ff_mkv_image_mime_tags[i].str))) {
2888                     st->codecpar->codec_id = ff_mkv_image_mime_tags[i].id;
2889                     break;
2890                 }
2891             }
2892 
2893             attachments[j].stream = st;
2894 
2895             if (st->codecpar->codec_id != AV_CODEC_ID_NONE) {
2896                 AVPacket *pkt = &st->attached_pic;
2897 
2898                 st->disposition         |= AV_DISPOSITION_ATTACHED_PIC;
2899                 st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
2900 
2901                 av_init_packet(pkt);
2902                 pkt->buf = av_buffer_ref(attachments[j].bin.buf);
2903                 if (!pkt->buf)
2904                     return AVERROR(ENOMEM);
2905                 pkt->data         = attachments[j].bin.data;
2906                 pkt->size         = attachments[j].bin.size;
2907                 pkt->stream_index = st->index;
2908                 pkt->flags       |= AV_PKT_FLAG_KEY;
2909             } else {
2910                 st->codecpar->codec_type = AVMEDIA_TYPE_ATTACHMENT;
2911                 if (ff_alloc_extradata(st->codecpar, attachments[j].bin.size))
2912                     break;
2913                 memcpy(st->codecpar->extradata, attachments[j].bin.data,
2914                        attachments[j].bin.size);
2915 
2916                 for (i = 0; ff_mkv_mime_tags[i].id != AV_CODEC_ID_NONE; i++) {
2917                     if (!strncmp(ff_mkv_mime_tags[i].str, attachments[j].mime,
2918                                 strlen(ff_mkv_mime_tags[i].str))) {
2919                         st->codecpar->codec_id = ff_mkv_mime_tags[i].id;
2920                         break;
2921                     }
2922                 }
2923             }
2924         }
2925     }
2926 
2927     chapters = chapters_list->elem;
2928     for (i = 0; i < chapters_list->nb_elem; i++)
2929         if (chapters[i].start != AV_NOPTS_VALUE && chapters[i].uid &&
2930             (max_start == 0 || chapters[i].start > max_start)) {
2931             chapters[i].chapter =
2932                 avpriv_new_chapter(s, chapters[i].uid,
2933                                    (AVRational) { 1, 1000000000 },
2934                                    chapters[i].start, chapters[i].end,
2935                                    chapters[i].title);
2936             if (chapters[i].chapter) {
2937                 av_dict_set(&chapters[i].chapter->metadata,
2938                             "title", chapters[i].title, 0);
2939             }
2940             max_start = chapters[i].start;
2941         }
2942 
2943     matroska_add_index_entries(matroska);
2944 
2945     matroska_convert_tags(s);
2946 
2947     return 0;
2948 fail:
2949     matroska_read_close(s);
2950     return res;
2951 }
2952 
2953 /*
2954  * Put one packet in an application-supplied AVPacket struct.
2955  * Returns 0 on success or -1 on failure.
2956  */
matroska_deliver_packet(MatroskaDemuxContext * matroska,AVPacket * pkt)2957 static int matroska_deliver_packet(MatroskaDemuxContext *matroska,
2958                                    AVPacket *pkt)
2959 {
2960     if (matroska->queue) {
2961         MatroskaTrack *tracks = matroska->tracks.elem;
2962         MatroskaTrack *track;
2963 
2964         ff_packet_list_get(&matroska->queue, &matroska->queue_end, pkt);
2965         track = &tracks[pkt->stream_index];
2966         if (track->has_palette) {
2967             uint8_t *pal = av_packet_new_side_data(pkt, AV_PKT_DATA_PALETTE, AVPALETTE_SIZE);
2968             if (!pal) {
2969                 av_log(matroska->ctx, AV_LOG_ERROR, "Cannot append palette to packet\n");
2970             } else {
2971                 memcpy(pal, track->palette, AVPALETTE_SIZE);
2972             }
2973             track->has_palette = 0;
2974         }
2975         return 0;
2976     }
2977 
2978     return -1;
2979 }
2980 
2981 /*
2982  * Free all packets in our internal queue.
2983  */
matroska_clear_queue(MatroskaDemuxContext * matroska)2984 static void matroska_clear_queue(MatroskaDemuxContext *matroska)
2985 {
2986     ff_packet_list_free(&matroska->queue, &matroska->queue_end);
2987 }
2988 
matroska_parse_laces(MatroskaDemuxContext * matroska,uint8_t ** buf,int size,int type,AVIOContext * pb,uint32_t lace_size[256],int * laces)2989 static int matroska_parse_laces(MatroskaDemuxContext *matroska, uint8_t **buf,
2990                                 int size, int type, AVIOContext *pb,
2991                                 uint32_t lace_size[256], int *laces)
2992 {
2993     int n;
2994     uint8_t *data = *buf;
2995 
2996     if (!type) {
2997         *laces    = 1;
2998         lace_size[0] = size;
2999         return 0;
3000     }
3001 
3002     av_assert0(size > 0);
3003     *laces    = *data + 1;
3004     data     += 1;
3005     size     -= 1;
3006 
3007     switch (type) {
3008     case 0x1: /* Xiph lacing */
3009     {
3010         uint8_t temp;
3011         uint32_t total = 0;
3012         for (n = 0; n < *laces - 1; n++) {
3013             lace_size[n] = 0;
3014 
3015             while (1) {
3016                 if (size <= total) {
3017                     return AVERROR_INVALIDDATA;
3018                 }
3019                 temp          = *data;
3020                 total        += temp;
3021                 lace_size[n] += temp;
3022                 data         += 1;
3023                 size         -= 1;
3024                 if (temp != 0xff)
3025                     break;
3026             }
3027         }
3028         if (size <= total) {
3029             return AVERROR_INVALIDDATA;
3030         }
3031 
3032         lace_size[n] = size - total;
3033         break;
3034     }
3035 
3036     case 0x2: /* fixed-size lacing */
3037         if (size % (*laces)) {
3038             return AVERROR_INVALIDDATA;
3039         }
3040         for (n = 0; n < *laces; n++)
3041             lace_size[n] = size / *laces;
3042         break;
3043 
3044     case 0x3: /* EBML lacing */
3045     {
3046         uint64_t num;
3047         uint64_t total;
3048         int offset;
3049 
3050         avio_skip(pb, 4);
3051 
3052         n = ebml_read_num(matroska, pb, 8, &num, 1);
3053         if (n < 0)
3054             return n;
3055         if (num > INT_MAX)
3056             return AVERROR_INVALIDDATA;
3057 
3058         total = lace_size[0] = num;
3059         offset = n;
3060         for (n = 1; n < *laces - 1; n++) {
3061             int64_t snum;
3062             int r;
3063             r = matroska_ebmlnum_sint(matroska, pb, &snum);
3064             if (r < 0)
3065                 return r;
3066             if (lace_size[n - 1] + snum > (uint64_t)INT_MAX)
3067                 return AVERROR_INVALIDDATA;
3068 
3069             lace_size[n] = lace_size[n - 1] + snum;
3070             total       += lace_size[n];
3071             offset      += r;
3072         }
3073         data += offset;
3074         size -= offset;
3075         if (size <= total) {
3076             return AVERROR_INVALIDDATA;
3077         }
3078         lace_size[*laces - 1] = size - total;
3079         break;
3080     }
3081     }
3082 
3083     *buf      = data;
3084 
3085     return 0;
3086 }
3087 
matroska_parse_rm_audio(MatroskaDemuxContext * matroska,MatroskaTrack * track,AVStream * st,uint8_t * data,int size,uint64_t timecode,int64_t pos)3088 static int matroska_parse_rm_audio(MatroskaDemuxContext *matroska,
3089                                    MatroskaTrack *track, AVStream *st,
3090                                    uint8_t *data, int size, uint64_t timecode,
3091                                    int64_t pos)
3092 {
3093     int a = st->codecpar->block_align;
3094     int sps = track->audio.sub_packet_size;
3095     int cfs = track->audio.coded_framesize;
3096     int h   = track->audio.sub_packet_h;
3097     int y   = track->audio.sub_packet_cnt;
3098     int w   = track->audio.frame_size;
3099     int x;
3100 
3101     if (!track->audio.pkt_cnt) {
3102         if (track->audio.sub_packet_cnt == 0)
3103             track->audio.buf_timecode = timecode;
3104         if (st->codecpar->codec_id == AV_CODEC_ID_RA_288) {
3105             if (size < cfs * h / 2) {
3106                 av_log(matroska->ctx, AV_LOG_ERROR,
3107                        "Corrupt int4 RM-style audio packet size\n");
3108                 return AVERROR_INVALIDDATA;
3109             }
3110             for (x = 0; x < h / 2; x++)
3111                 memcpy(track->audio.buf + x * 2 * w + y * cfs,
3112                        data + x * cfs, cfs);
3113         } else if (st->codecpar->codec_id == AV_CODEC_ID_SIPR) {
3114             if (size < w) {
3115                 av_log(matroska->ctx, AV_LOG_ERROR,
3116                        "Corrupt sipr RM-style audio packet size\n");
3117                 return AVERROR_INVALIDDATA;
3118             }
3119             memcpy(track->audio.buf + y * w, data, w);
3120         } else {
3121             if (size < sps * w / sps || h<=0 || w%sps) {
3122                 av_log(matroska->ctx, AV_LOG_ERROR,
3123                        "Corrupt generic RM-style audio packet size\n");
3124                 return AVERROR_INVALIDDATA;
3125             }
3126             for (x = 0; x < w / sps; x++)
3127                 memcpy(track->audio.buf +
3128                        sps * (h * x + ((h + 1) / 2) * (y & 1) + (y >> 1)),
3129                        data + x * sps, sps);
3130         }
3131 
3132         if (++track->audio.sub_packet_cnt >= h) {
3133             if (st->codecpar->codec_id == AV_CODEC_ID_SIPR) {
3134 #if CONFIG_SIPR_DECODER
3135                 ff_rm_reorder_sipr_data(track->audio.buf, h, w);
3136 #else
3137                 return AVERROR_INVALIDDATA;
3138 #endif
3139             }
3140             track->audio.sub_packet_cnt = 0;
3141             track->audio.pkt_cnt        = h * w / a;
3142         }
3143     }
3144 
3145     while (track->audio.pkt_cnt) {
3146         int ret;
3147         AVPacket pktl, *pkt = &pktl;
3148 
3149         ret = av_new_packet(pkt, a);
3150         if (ret < 0) {
3151             return ret;
3152         }
3153         memcpy(pkt->data,
3154                track->audio.buf + a * (h * w / a - track->audio.pkt_cnt--),
3155                a);
3156         pkt->pts                  = track->audio.buf_timecode;
3157         track->audio.buf_timecode = AV_NOPTS_VALUE;
3158         pkt->pos                  = pos;
3159         pkt->stream_index         = st->index;
3160         ret = ff_packet_list_put(&matroska->queue, &matroska->queue_end, pkt, 0);
3161         if (ret < 0) {
3162             av_packet_unref(pkt);
3163             return AVERROR(ENOMEM);
3164         }
3165     }
3166 
3167     return 0;
3168 }
3169 
3170 /* reconstruct full wavpack blocks from mangled matroska ones */
matroska_parse_wavpack(MatroskaTrack * track,uint8_t * src,uint8_t ** pdst,int * size)3171 static int matroska_parse_wavpack(MatroskaTrack *track, uint8_t *src,
3172                                   uint8_t **pdst, int *size)
3173 {
3174     uint8_t *dst = NULL;
3175     int dstlen   = 0;
3176     int srclen   = *size;
3177     uint32_t samples;
3178     uint16_t ver;
3179     int ret, offset = 0;
3180 
3181     if (srclen < 12 || track->stream->codecpar->extradata_size < 2)
3182         return AVERROR_INVALIDDATA;
3183 
3184     ver = AV_RL16(track->stream->codecpar->extradata);
3185 
3186     samples = AV_RL32(src);
3187     src    += 4;
3188     srclen -= 4;
3189 
3190     while (srclen >= 8) {
3191         int multiblock;
3192         uint32_t blocksize;
3193         uint8_t *tmp;
3194 
3195         uint32_t flags = AV_RL32(src);
3196         uint32_t crc   = AV_RL32(src + 4);
3197         src    += 8;
3198         srclen -= 8;
3199 
3200         multiblock = (flags & 0x1800) != 0x1800;
3201         if (multiblock) {
3202             if (srclen < 4) {
3203                 ret = AVERROR_INVALIDDATA;
3204                 goto fail;
3205             }
3206             blocksize = AV_RL32(src);
3207             src      += 4;
3208             srclen   -= 4;
3209         } else
3210             blocksize = srclen;
3211 
3212         if (blocksize > srclen) {
3213             ret = AVERROR_INVALIDDATA;
3214             goto fail;
3215         }
3216 
3217         tmp = av_realloc(dst, dstlen + blocksize + 32 + AV_INPUT_BUFFER_PADDING_SIZE);
3218         if (!tmp) {
3219             ret = AVERROR(ENOMEM);
3220             goto fail;
3221         }
3222         dst     = tmp;
3223         dstlen += blocksize + 32;
3224 
3225         AV_WL32(dst + offset, MKTAG('w', 'v', 'p', 'k'));   // tag
3226         AV_WL32(dst + offset +  4, blocksize + 24);         // blocksize - 8
3227         AV_WL16(dst + offset +  8, ver);                    // version
3228         AV_WL16(dst + offset + 10, 0);                      // track/index_no
3229         AV_WL32(dst + offset + 12, 0);                      // total samples
3230         AV_WL32(dst + offset + 16, 0);                      // block index
3231         AV_WL32(dst + offset + 20, samples);                // number of samples
3232         AV_WL32(dst + offset + 24, flags);                  // flags
3233         AV_WL32(dst + offset + 28, crc);                    // crc
3234         memcpy(dst + offset + 32, src, blocksize);          // block data
3235 
3236         src    += blocksize;
3237         srclen -= blocksize;
3238         offset += blocksize + 32;
3239     }
3240 
3241     memset(dst + dstlen, 0, AV_INPUT_BUFFER_PADDING_SIZE);
3242 
3243     *pdst = dst;
3244     *size = dstlen;
3245 
3246     return 0;
3247 
3248 fail:
3249     av_freep(&dst);
3250     return ret;
3251 }
3252 
matroska_parse_prores(MatroskaTrack * track,uint8_t * src,uint8_t ** pdst,int * size)3253 static int matroska_parse_prores(MatroskaTrack *track, uint8_t *src,
3254                                  uint8_t **pdst, int *size)
3255 {
3256     uint8_t *dst;
3257     int dstlen = *size + 8;
3258 
3259         dst = av_malloc(dstlen + AV_INPUT_BUFFER_PADDING_SIZE);
3260         if (!dst)
3261             return AVERROR(ENOMEM);
3262 
3263         AV_WB32(dst, dstlen);
3264         AV_WB32(dst + 4, MKBETAG('i', 'c', 'p', 'f'));
3265         memcpy(dst + 8, src, dstlen - 8);
3266         memset(dst + dstlen, 0, AV_INPUT_BUFFER_PADDING_SIZE);
3267 
3268     *pdst = dst;
3269     *size = dstlen;
3270 
3271     return 0;
3272 }
3273 
matroska_parse_webvtt(MatroskaDemuxContext * matroska,MatroskaTrack * track,AVStream * st,uint8_t * data,int data_len,uint64_t timecode,uint64_t duration,int64_t pos)3274 static int matroska_parse_webvtt(MatroskaDemuxContext *matroska,
3275                                  MatroskaTrack *track,
3276                                  AVStream *st,
3277                                  uint8_t *data, int data_len,
3278                                  uint64_t timecode,
3279                                  uint64_t duration,
3280                                  int64_t pos)
3281 {
3282     AVPacket pktl, *pkt = &pktl;
3283     uint8_t *id, *settings, *text, *buf;
3284     int id_len, settings_len, text_len;
3285     uint8_t *p, *q;
3286     int err;
3287 
3288     if (data_len <= 0)
3289         return AVERROR_INVALIDDATA;
3290 
3291     p = data;
3292     q = data + data_len;
3293 
3294     id = p;
3295     id_len = -1;
3296     while (p < q) {
3297         if (*p == '\r' || *p == '\n') {
3298             id_len = p - id;
3299             if (*p == '\r')
3300                 p++;
3301             break;
3302         }
3303         p++;
3304     }
3305 
3306     if (p >= q || *p != '\n')
3307         return AVERROR_INVALIDDATA;
3308     p++;
3309 
3310     settings = p;
3311     settings_len = -1;
3312     while (p < q) {
3313         if (*p == '\r' || *p == '\n') {
3314             settings_len = p - settings;
3315             if (*p == '\r')
3316                 p++;
3317             break;
3318         }
3319         p++;
3320     }
3321 
3322     if (p >= q || *p != '\n')
3323         return AVERROR_INVALIDDATA;
3324     p++;
3325 
3326     text = p;
3327     text_len = q - p;
3328     while (text_len > 0) {
3329         const int len = text_len - 1;
3330         const uint8_t c = p[len];
3331         if (c != '\r' && c != '\n')
3332             break;
3333         text_len = len;
3334     }
3335 
3336     if (text_len <= 0)
3337         return AVERROR_INVALIDDATA;
3338 
3339     err = av_new_packet(pkt, text_len);
3340     if (err < 0) {
3341         return err;
3342     }
3343 
3344     memcpy(pkt->data, text, text_len);
3345 
3346     if (id_len > 0) {
3347         buf = av_packet_new_side_data(pkt,
3348                                       AV_PKT_DATA_WEBVTT_IDENTIFIER,
3349                                       id_len);
3350         if (!buf) {
3351             av_packet_unref(pkt);
3352             return AVERROR(ENOMEM);
3353         }
3354         memcpy(buf, id, id_len);
3355     }
3356 
3357     if (settings_len > 0) {
3358         buf = av_packet_new_side_data(pkt,
3359                                       AV_PKT_DATA_WEBVTT_SETTINGS,
3360                                       settings_len);
3361         if (!buf) {
3362             av_packet_unref(pkt);
3363             return AVERROR(ENOMEM);
3364         }
3365         memcpy(buf, settings, settings_len);
3366     }
3367 
3368     // Do we need this for subtitles?
3369     // pkt->flags = AV_PKT_FLAG_KEY;
3370 
3371     pkt->stream_index = st->index;
3372     pkt->pts = timecode;
3373 
3374     // Do we need this for subtitles?
3375     // pkt->dts = timecode;
3376 
3377     pkt->duration = duration;
3378     pkt->pos = pos;
3379 
3380     err = ff_packet_list_put(&matroska->queue, &matroska->queue_end, pkt, 0);
3381     if (err < 0) {
3382         av_packet_unref(pkt);
3383         return AVERROR(ENOMEM);
3384     }
3385 
3386     return 0;
3387 }
3388 
matroska_parse_frame(MatroskaDemuxContext * matroska,MatroskaTrack * track,AVStream * st,AVBufferRef * buf,uint8_t * data,int pkt_size,uint64_t timecode,uint64_t lace_duration,int64_t pos,int is_keyframe,uint8_t * additional,uint64_t additional_id,int additional_size,int64_t discard_padding)3389 static int matroska_parse_frame(MatroskaDemuxContext *matroska,
3390                                 MatroskaTrack *track, AVStream *st,
3391                                 AVBufferRef *buf, uint8_t *data, int pkt_size,
3392                                 uint64_t timecode, uint64_t lace_duration,
3393                                 int64_t pos, int is_keyframe,
3394                                 uint8_t *additional, uint64_t additional_id, int additional_size,
3395                                 int64_t discard_padding)
3396 {
3397     MatroskaTrackEncoding *encodings = track->encodings.elem;
3398     uint8_t *pkt_data = data;
3399     int res;
3400     AVPacket pktl, *pkt = &pktl;
3401 
3402     if (encodings && !encodings->type && encodings->scope & 1) {
3403         res = matroska_decode_buffer(&pkt_data, &pkt_size, track);
3404         if (res < 0)
3405             return res;
3406     }
3407 
3408     if (st->codecpar->codec_id == AV_CODEC_ID_WAVPACK) {
3409         uint8_t *wv_data;
3410         res = matroska_parse_wavpack(track, pkt_data, &wv_data, &pkt_size);
3411         if (res < 0) {
3412             av_log(matroska->ctx, AV_LOG_ERROR,
3413                    "Error parsing a wavpack block.\n");
3414             goto fail;
3415         }
3416         if (pkt_data != data)
3417             av_freep(&pkt_data);
3418         pkt_data = wv_data;
3419     }
3420 
3421     if (st->codecpar->codec_id == AV_CODEC_ID_PRORES &&
3422         AV_RB32(pkt_data + 4)  != MKBETAG('i', 'c', 'p', 'f')) {
3423         uint8_t *pr_data;
3424         res = matroska_parse_prores(track, pkt_data, &pr_data, &pkt_size);
3425         if (res < 0) {
3426             av_log(matroska->ctx, AV_LOG_ERROR,
3427                    "Error parsing a prores block.\n");
3428             goto fail;
3429         }
3430         if (pkt_data != data)
3431             av_freep(&pkt_data);
3432         pkt_data = pr_data;
3433     }
3434 
3435     av_init_packet(pkt);
3436     if (pkt_data != data)
3437         pkt->buf = av_buffer_create(pkt_data, pkt_size + AV_INPUT_BUFFER_PADDING_SIZE,
3438                                     NULL, NULL, 0);
3439     else
3440         pkt->buf = av_buffer_ref(buf);
3441 
3442     if (!pkt->buf) {
3443         res = AVERROR(ENOMEM);
3444         goto fail;
3445     }
3446 
3447     pkt->data         = pkt_data;
3448     pkt->size         = pkt_size;
3449     pkt->flags        = is_keyframe;
3450     pkt->stream_index = st->index;
3451 
3452     if (additional_size > 0) {
3453         uint8_t *side_data = av_packet_new_side_data(pkt,
3454                                                      AV_PKT_DATA_MATROSKA_BLOCKADDITIONAL,
3455                                                      additional_size + 8);
3456         if (!side_data) {
3457             av_packet_unref(pkt);
3458             return AVERROR(ENOMEM);
3459         }
3460         AV_WB64(side_data, additional_id);
3461         memcpy(side_data + 8, additional, additional_size);
3462     }
3463 
3464     if (discard_padding) {
3465         uint8_t *side_data = av_packet_new_side_data(pkt,
3466                                                      AV_PKT_DATA_SKIP_SAMPLES,
3467                                                      10);
3468         if (!side_data) {
3469             av_packet_unref(pkt);
3470             return AVERROR(ENOMEM);
3471         }
3472         discard_padding = av_rescale_q(discard_padding,
3473                                             (AVRational){1, 1000000000},
3474                                             (AVRational){1, st->codecpar->sample_rate});
3475         if (discard_padding > 0) {
3476             AV_WL32(side_data + 4, discard_padding);
3477         } else {
3478             AV_WL32(side_data, -discard_padding);
3479         }
3480     }
3481 
3482     if (track->ms_compat)
3483         pkt->dts = timecode;
3484     else
3485         pkt->pts = timecode;
3486     pkt->pos = pos;
3487     pkt->duration = lace_duration;
3488 
3489 #if FF_API_CONVERGENCE_DURATION
3490 FF_DISABLE_DEPRECATION_WARNINGS
3491     if (st->codecpar->codec_id == AV_CODEC_ID_SUBRIP) {
3492         pkt->convergence_duration = lace_duration;
3493     }
3494 FF_ENABLE_DEPRECATION_WARNINGS
3495 #endif
3496 
3497     res = ff_packet_list_put(&matroska->queue, &matroska->queue_end, pkt, 0);
3498     if (res < 0) {
3499         av_packet_unref(pkt);
3500         return AVERROR(ENOMEM);
3501     }
3502 
3503     return 0;
3504 
3505 fail:
3506     if (pkt_data != data)
3507         av_freep(&pkt_data);
3508     return res;
3509 }
3510 
matroska_parse_block(MatroskaDemuxContext * matroska,AVBufferRef * buf,uint8_t * data,int size,int64_t pos,uint64_t cluster_time,uint64_t block_duration,int is_keyframe,uint8_t * additional,uint64_t additional_id,int additional_size,int64_t cluster_pos,int64_t discard_padding)3511 static int matroska_parse_block(MatroskaDemuxContext *matroska, AVBufferRef *buf, uint8_t *data,
3512                                 int size, int64_t pos, uint64_t cluster_time,
3513                                 uint64_t block_duration, int is_keyframe,
3514                                 uint8_t *additional, uint64_t additional_id, int additional_size,
3515                                 int64_t cluster_pos, int64_t discard_padding)
3516 {
3517     uint64_t timecode = AV_NOPTS_VALUE;
3518     MatroskaTrack *track;
3519     AVIOContext pb;
3520     int res = 0;
3521     AVStream *st;
3522     int16_t block_time;
3523     uint32_t lace_size[256];
3524     int n, flags, laces = 0;
3525     uint64_t num;
3526     int trust_default_duration = 1;
3527 
3528     ffio_init_context(&pb, data, size, 0, NULL, NULL, NULL, NULL);
3529 
3530     if ((n = ebml_read_num(matroska, &pb, 8, &num, 1)) < 0)
3531         return n;
3532     data += n;
3533     size -= n;
3534 
3535     track = matroska_find_track_by_num(matroska, num);
3536     if (!track || !track->stream) {
3537         av_log(matroska->ctx, AV_LOG_INFO,
3538                "Invalid stream %"PRIu64"\n", num);
3539         return AVERROR_INVALIDDATA;
3540     } else if (size <= 3)
3541         return 0;
3542     st = track->stream;
3543     if (st->discard >= AVDISCARD_ALL)
3544         return res;
3545     av_assert1(block_duration != AV_NOPTS_VALUE);
3546 
3547     block_time = sign_extend(AV_RB16(data), 16);
3548     data      += 2;
3549     flags      = *data++;
3550     size      -= 3;
3551     if (is_keyframe == -1)
3552         is_keyframe = flags & 0x80 ? AV_PKT_FLAG_KEY : 0;
3553 
3554     if (cluster_time != (uint64_t) -1 &&
3555         (block_time >= 0 || cluster_time >= -block_time)) {
3556         timecode = cluster_time + block_time - track->codec_delay_in_track_tb;
3557         if (track->type == MATROSKA_TRACK_TYPE_SUBTITLE &&
3558             timecode < track->end_timecode)
3559             is_keyframe = 0;  /* overlapping subtitles are not key frame */
3560         if (is_keyframe) {
3561             ff_reduce_index(matroska->ctx, st->index);
3562             av_add_index_entry(st, cluster_pos, timecode, 0, 0,
3563                                AVINDEX_KEYFRAME);
3564         }
3565     }
3566 
3567     if (matroska->skip_to_keyframe &&
3568         track->type != MATROSKA_TRACK_TYPE_SUBTITLE) {
3569         // Compare signed timecodes. Timecode may be negative due to codec delay
3570         // offset. We don't support timestamps greater than int64_t anyway - see
3571         // AVPacket's pts.
3572         if ((int64_t)timecode < (int64_t)matroska->skip_to_timecode)
3573             return res;
3574         if (is_keyframe)
3575             matroska->skip_to_keyframe = 0;
3576         else if (!st->skip_to_keyframe) {
3577             av_log(matroska->ctx, AV_LOG_ERROR, "File is broken, keyframes not correctly marked!\n");
3578             matroska->skip_to_keyframe = 0;
3579         }
3580     }
3581 
3582     res = matroska_parse_laces(matroska, &data, size, (flags & 0x06) >> 1,
3583                                &pb, lace_size, &laces);
3584     if (res < 0) {
3585         av_log(matroska->ctx, AV_LOG_ERROR, "Error parsing frame sizes.\n");
3586         return res;
3587     }
3588 
3589     if (track->audio.samplerate == 8000) {
3590         // If this is needed for more codecs, then add them here
3591         if (st->codecpar->codec_id == AV_CODEC_ID_AC3) {
3592             if (track->audio.samplerate != st->codecpar->sample_rate || !st->codecpar->frame_size)
3593                 trust_default_duration = 0;
3594         }
3595     }
3596 
3597     if (!block_duration && trust_default_duration)
3598         block_duration = track->default_duration * laces / matroska->time_scale;
3599 
3600     if (cluster_time != (uint64_t)-1 && (block_time >= 0 || cluster_time >= -block_time))
3601         track->end_timecode =
3602             FFMAX(track->end_timecode, timecode + block_duration);
3603 
3604     for (n = 0; n < laces; n++) {
3605         int64_t lace_duration = block_duration*(n+1) / laces - block_duration*n / laces;
3606 
3607         if ((st->codecpar->codec_id == AV_CODEC_ID_RA_288 ||
3608              st->codecpar->codec_id == AV_CODEC_ID_COOK   ||
3609              st->codecpar->codec_id == AV_CODEC_ID_SIPR   ||
3610              st->codecpar->codec_id == AV_CODEC_ID_ATRAC3) &&
3611             st->codecpar->block_align && track->audio.sub_packet_size) {
3612 #if CONFIG_RA_288_DECODER || CONFIG_COOK_DECODER || CONFIG_ATRAC3_DECODER || CONFIG_SIPR_DECODER
3613             res = matroska_parse_rm_audio(matroska, track, st, data,
3614                                           lace_size[n],
3615                                           timecode, pos);
3616 #else
3617             res = AVERROR_INVALIDDATA;
3618 #endif
3619             if (res)
3620                 return res;
3621 
3622         } else if (st->codecpar->codec_id == AV_CODEC_ID_WEBVTT) {
3623             res = matroska_parse_webvtt(matroska, track, st,
3624                                         data, lace_size[n],
3625                                         timecode, lace_duration,
3626                                         pos);
3627             if (res)
3628                 return res;
3629         } else {
3630             res = matroska_parse_frame(matroska, track, st, buf, data, lace_size[n],
3631                                        timecode, lace_duration, pos,
3632                                        !n ? is_keyframe : 0,
3633                                        additional, additional_id, additional_size,
3634                                        discard_padding);
3635             if (res)
3636                 return res;
3637         }
3638 
3639         if (timecode != AV_NOPTS_VALUE)
3640             timecode = lace_duration ? timecode + lace_duration : AV_NOPTS_VALUE;
3641         data += lace_size[n];
3642     }
3643 
3644     return 0;
3645 }
3646 
matroska_parse_cluster(MatroskaDemuxContext * matroska)3647 static int matroska_parse_cluster(MatroskaDemuxContext *matroska)
3648 {
3649     MatroskaCluster *cluster = &matroska->current_cluster;
3650     MatroskaBlock     *block = &cluster->block;
3651     int res;
3652 
3653     if (matroska->num_levels > 2)
3654       return AVERROR_INVALIDDATA;
3655 
3656     if (matroska->num_levels == 1) {
3657         res = ebml_parse(matroska, matroska_segment, NULL);
3658 
3659         if (res == 1) {
3660             /* Found a cluster: subtract the size of the ID already read. */
3661             cluster->pos = avio_tell(matroska->ctx->pb) - 4;
3662 
3663             res = ebml_parse(matroska, matroska_cluster_enter, cluster);
3664             if (res < 0)
3665                 return res;
3666         }
3667     }
3668 
3669     if (matroska->num_levels == 2) {
3670         /* We are inside a cluster. */
3671         res = ebml_parse(matroska, matroska_cluster_parsing, cluster);
3672 
3673         if (res >= 0 && block->bin.size > 0) {
3674             int is_keyframe = block->non_simple ? block->reference == INT64_MIN : -1;
3675             uint8_t* additional = block->additional.size > 0 ?
3676                                     block->additional.data : NULL;
3677 
3678             res = matroska_parse_block(matroska, block->bin.buf, block->bin.data,
3679                                        block->bin.size, block->bin.pos,
3680                                        cluster->timecode, block->duration,
3681                                        is_keyframe, additional, block->additional_id,
3682                                        block->additional.size, cluster->pos,
3683                                        block->discard_padding);
3684         }
3685 
3686         ebml_free(matroska_blockgroup, block);
3687         memset(block, 0, sizeof(*block));
3688     } else if (!matroska->num_levels) {
3689         if (!avio_feof(matroska->ctx->pb)) {
3690             avio_r8(matroska->ctx->pb);
3691             if (!avio_feof(matroska->ctx->pb)) {
3692                 av_log(matroska->ctx, AV_LOG_WARNING, "File extends beyond "
3693                        "end of segment.\n");
3694                 return AVERROR_INVALIDDATA;
3695             }
3696         }
3697         matroska->done = 1;
3698         return AVERROR_EOF;
3699     }
3700 
3701     return res;
3702 }
3703 
matroska_read_packet(AVFormatContext * s,AVPacket * pkt)3704 static int matroska_read_packet(AVFormatContext *s, AVPacket *pkt)
3705 {
3706     MatroskaDemuxContext *matroska = s->priv_data;
3707     int ret = 0;
3708 
3709     if (matroska->resync_pos == -1) {
3710         // This can only happen if generic seeking has been used.
3711         matroska->resync_pos = avio_tell(s->pb);
3712     }
3713 
3714     while (matroska_deliver_packet(matroska, pkt)) {
3715         if (matroska->done)
3716             return (ret < 0) ? ret : AVERROR_EOF;
3717         if (matroska_parse_cluster(matroska) < 0 && !matroska->done)
3718             ret = matroska_resync(matroska, matroska->resync_pos);
3719     }
3720 
3721     return 0;
3722 }
3723 
matroska_read_seek(AVFormatContext * s,int stream_index,int64_t timestamp,int flags)3724 static int matroska_read_seek(AVFormatContext *s, int stream_index,
3725                               int64_t timestamp, int flags)
3726 {
3727     MatroskaDemuxContext *matroska = s->priv_data;
3728     MatroskaTrack *tracks = NULL;
3729     AVStream *st = s->streams[stream_index];
3730     int i, index;
3731 
3732     /* Parse the CUES now since we need the index data to seek. */
3733     if (matroska->cues_parsing_deferred > 0) {
3734         matroska->cues_parsing_deferred = 0;
3735         matroska_parse_cues(matroska);
3736     }
3737 
3738     if (!st->nb_index_entries)
3739         goto err;
3740     timestamp = FFMAX(timestamp, st->index_entries[0].timestamp);
3741 
3742     if ((index = av_index_search_timestamp(st, timestamp, flags)) < 0 || index == st->nb_index_entries - 1) {
3743         matroska_reset_status(matroska, 0, st->index_entries[st->nb_index_entries - 1].pos);
3744         while ((index = av_index_search_timestamp(st, timestamp, flags)) < 0 || index == st->nb_index_entries - 1) {
3745             matroska_clear_queue(matroska);
3746             if (matroska_parse_cluster(matroska) < 0)
3747                 break;
3748         }
3749     }
3750 
3751     matroska_clear_queue(matroska);
3752     if (index < 0 || (matroska->cues_parsing_deferred < 0 && index == st->nb_index_entries - 1))
3753         goto err;
3754 
3755     tracks = matroska->tracks.elem;
3756     for (i = 0; i < matroska->tracks.nb_elem; i++) {
3757         tracks[i].audio.pkt_cnt        = 0;
3758         tracks[i].audio.sub_packet_cnt = 0;
3759         tracks[i].audio.buf_timecode   = AV_NOPTS_VALUE;
3760         tracks[i].end_timecode         = 0;
3761     }
3762 
3763     /* We seek to a level 1 element, so set the appropriate status. */
3764     matroska_reset_status(matroska, 0, st->index_entries[index].pos);
3765     if (flags & AVSEEK_FLAG_ANY) {
3766         st->skip_to_keyframe = 0;
3767         matroska->skip_to_timecode = timestamp;
3768     } else {
3769         st->skip_to_keyframe = 1;
3770         matroska->skip_to_timecode = st->index_entries[index].timestamp;
3771     }
3772     matroska->skip_to_keyframe = 1;
3773     matroska->done             = 0;
3774     ff_update_cur_dts(s, st, st->index_entries[index].timestamp);
3775     return 0;
3776 err:
3777     // slightly hackish but allows proper fallback to
3778     // the generic seeking code.
3779     matroska_reset_status(matroska, 0, -1);
3780     matroska->resync_pos = -1;
3781     matroska_clear_queue(matroska);
3782     st->skip_to_keyframe =
3783     matroska->skip_to_keyframe = 0;
3784     matroska->done = 0;
3785     return -1;
3786 }
3787 
matroska_read_close(AVFormatContext * s)3788 static int matroska_read_close(AVFormatContext *s)
3789 {
3790     MatroskaDemuxContext *matroska = s->priv_data;
3791     MatroskaTrack *tracks = matroska->tracks.elem;
3792     int n;
3793 
3794     matroska_clear_queue(matroska);
3795 
3796     for (n = 0; n < matroska->tracks.nb_elem; n++)
3797         if (tracks[n].type == MATROSKA_TRACK_TYPE_AUDIO)
3798             av_freep(&tracks[n].audio.buf);
3799     ebml_free(matroska_segment, matroska);
3800 
3801     return 0;
3802 }
3803 
3804 typedef struct {
3805     int64_t start_time_ns;
3806     int64_t end_time_ns;
3807     int64_t start_offset;
3808     int64_t end_offset;
3809 } CueDesc;
3810 
3811 /* This function searches all the Cues and returns the CueDesc corresponding to
3812  * the timestamp ts. Returned CueDesc will be such that start_time_ns <= ts <
3813  * end_time_ns. All 4 fields will be set to -1 if ts >= file's duration.
3814  */
get_cue_desc(AVFormatContext * s,int64_t ts,int64_t cues_start)3815 static CueDesc get_cue_desc(AVFormatContext *s, int64_t ts, int64_t cues_start) {
3816     MatroskaDemuxContext *matroska = s->priv_data;
3817     CueDesc cue_desc;
3818     int i;
3819     int nb_index_entries = s->streams[0]->nb_index_entries;
3820     AVIndexEntry *index_entries = s->streams[0]->index_entries;
3821     if (ts >= matroska->duration * matroska->time_scale) return (CueDesc) {-1, -1, -1, -1};
3822     for (i = 1; i < nb_index_entries; i++) {
3823         if (index_entries[i - 1].timestamp * matroska->time_scale <= ts &&
3824             index_entries[i].timestamp * matroska->time_scale > ts) {
3825             break;
3826         }
3827     }
3828     --i;
3829     cue_desc.start_time_ns = index_entries[i].timestamp * matroska->time_scale;
3830     cue_desc.start_offset = index_entries[i].pos - matroska->segment_start;
3831     if (i != nb_index_entries - 1) {
3832         cue_desc.end_time_ns = index_entries[i + 1].timestamp * matroska->time_scale;
3833         cue_desc.end_offset = index_entries[i + 1].pos - matroska->segment_start;
3834     } else {
3835         cue_desc.end_time_ns = matroska->duration * matroska->time_scale;
3836         // FIXME: this needs special handling for files where Cues appear
3837         // before Clusters. the current logic assumes Cues appear after
3838         // Clusters.
3839         cue_desc.end_offset = cues_start - matroska->segment_start;
3840     }
3841     return cue_desc;
3842 }
3843 
webm_clusters_start_with_keyframe(AVFormatContext * s)3844 static int webm_clusters_start_with_keyframe(AVFormatContext *s)
3845 {
3846     MatroskaDemuxContext *matroska = s->priv_data;
3847     uint32_t id = matroska->current_id;
3848     int64_t cluster_pos, before_pos;
3849     int index, rv = 1;
3850     if (s->streams[0]->nb_index_entries <= 0) return 0;
3851     // seek to the first cluster using cues.
3852     index = av_index_search_timestamp(s->streams[0], 0, 0);
3853     if (index < 0)  return 0;
3854     cluster_pos = s->streams[0]->index_entries[index].pos;
3855     before_pos = avio_tell(s->pb);
3856     while (1) {
3857         uint64_t cluster_id, cluster_length;
3858         int read;
3859         AVPacket *pkt;
3860         avio_seek(s->pb, cluster_pos, SEEK_SET);
3861         // read cluster id and length
3862         read = ebml_read_num(matroska, matroska->ctx->pb, 4, &cluster_id, 1);
3863         if (read < 0 || cluster_id != 0xF43B675) // done with all clusters
3864             break;
3865         read = ebml_read_length(matroska, matroska->ctx->pb, &cluster_length);
3866         if (read < 0)
3867             break;
3868 
3869         matroska_reset_status(matroska, 0, cluster_pos);
3870         matroska_clear_queue(matroska);
3871         if (matroska_parse_cluster(matroska) < 0 ||
3872             !matroska->queue) {
3873             break;
3874         }
3875         pkt = &matroska->queue->pkt;
3876         // 4 + read is the length of the cluster id and the cluster length field.
3877         cluster_pos += 4 + read + cluster_length;
3878         if (!(pkt->flags & AV_PKT_FLAG_KEY)) {
3879             rv = 0;
3880             break;
3881         }
3882     }
3883 
3884     /* Restore the status after matroska_read_header: */
3885     matroska_reset_status(matroska, id, before_pos);
3886 
3887     return rv;
3888 }
3889 
buffer_size_after_time_downloaded(int64_t time_ns,double search_sec,int64_t bps,double min_buffer,double * buffer,double * sec_to_download,AVFormatContext * s,int64_t cues_start)3890 static int buffer_size_after_time_downloaded(int64_t time_ns, double search_sec, int64_t bps,
3891                                              double min_buffer, double* buffer,
3892                                              double* sec_to_download, AVFormatContext *s,
3893                                              int64_t cues_start)
3894 {
3895     double nano_seconds_per_second = 1000000000.0;
3896     double time_sec = time_ns / nano_seconds_per_second;
3897     int rv = 0;
3898     int64_t time_to_search_ns = (int64_t)(search_sec * nano_seconds_per_second);
3899     int64_t end_time_ns = time_ns + time_to_search_ns;
3900     double sec_downloaded = 0.0;
3901     CueDesc desc_curr = get_cue_desc(s, time_ns, cues_start);
3902     if (desc_curr.start_time_ns == -1)
3903       return -1;
3904     *sec_to_download = 0.0;
3905 
3906     // Check for non cue start time.
3907     if (time_ns > desc_curr.start_time_ns) {
3908       int64_t cue_nano = desc_curr.end_time_ns - time_ns;
3909       double percent = (double)(cue_nano) / (desc_curr.end_time_ns - desc_curr.start_time_ns);
3910       double cueBytes = (desc_curr.end_offset - desc_curr.start_offset) * percent;
3911       double timeToDownload = (cueBytes * 8.0) / bps;
3912 
3913       sec_downloaded += (cue_nano / nano_seconds_per_second) - timeToDownload;
3914       *sec_to_download += timeToDownload;
3915 
3916       // Check if the search ends within the first cue.
3917       if (desc_curr.end_time_ns >= end_time_ns) {
3918           double desc_end_time_sec = desc_curr.end_time_ns / nano_seconds_per_second;
3919           double percent_to_sub = search_sec / (desc_end_time_sec - time_sec);
3920           sec_downloaded = percent_to_sub * sec_downloaded;
3921           *sec_to_download = percent_to_sub * *sec_to_download;
3922       }
3923 
3924       if ((sec_downloaded + *buffer) <= min_buffer) {
3925           return 1;
3926       }
3927 
3928       // Get the next Cue.
3929       desc_curr = get_cue_desc(s, desc_curr.end_time_ns, cues_start);
3930     }
3931 
3932     while (desc_curr.start_time_ns != -1) {
3933         int64_t desc_bytes = desc_curr.end_offset - desc_curr.start_offset;
3934         int64_t desc_ns = desc_curr.end_time_ns - desc_curr.start_time_ns;
3935         double desc_sec = desc_ns / nano_seconds_per_second;
3936         double bits = (desc_bytes * 8.0);
3937         double time_to_download = bits / bps;
3938 
3939         sec_downloaded += desc_sec - time_to_download;
3940         *sec_to_download += time_to_download;
3941 
3942         if (desc_curr.end_time_ns >= end_time_ns) {
3943             double desc_end_time_sec = desc_curr.end_time_ns / nano_seconds_per_second;
3944             double percent_to_sub = search_sec / (desc_end_time_sec - time_sec);
3945             sec_downloaded = percent_to_sub * sec_downloaded;
3946             *sec_to_download = percent_to_sub * *sec_to_download;
3947 
3948             if ((sec_downloaded + *buffer) <= min_buffer)
3949                 rv = 1;
3950             break;
3951         }
3952 
3953         if ((sec_downloaded + *buffer) <= min_buffer) {
3954             rv = 1;
3955             break;
3956         }
3957 
3958         desc_curr = get_cue_desc(s, desc_curr.end_time_ns, cues_start);
3959     }
3960     *buffer = *buffer + sec_downloaded;
3961     return rv;
3962 }
3963 
3964 /* This function computes the bandwidth of the WebM file with the help of
3965  * buffer_size_after_time_downloaded() function. Both of these functions are
3966  * adapted from WebM Tools project and are adapted to work with FFmpeg's
3967  * Matroska parsing mechanism.
3968  *
3969  * Returns the bandwidth of the file on success; -1 on error.
3970  * */
webm_dash_manifest_compute_bandwidth(AVFormatContext * s,int64_t cues_start)3971 static int64_t webm_dash_manifest_compute_bandwidth(AVFormatContext *s, int64_t cues_start)
3972 {
3973     MatroskaDemuxContext *matroska = s->priv_data;
3974     AVStream *st = s->streams[0];
3975     double bandwidth = 0.0;
3976     int i;
3977 
3978     for (i = 0; i < st->nb_index_entries; i++) {
3979         int64_t prebuffer_ns = 1000000000;
3980         int64_t time_ns = st->index_entries[i].timestamp * matroska->time_scale;
3981         double nano_seconds_per_second = 1000000000.0;
3982         int64_t prebuffered_ns = time_ns + prebuffer_ns;
3983         double prebuffer_bytes = 0.0;
3984         int64_t temp_prebuffer_ns = prebuffer_ns;
3985         int64_t pre_bytes, pre_ns;
3986         double pre_sec, prebuffer, bits_per_second;
3987         CueDesc desc_beg = get_cue_desc(s, time_ns, cues_start);
3988 
3989         // Start with the first Cue.
3990         CueDesc desc_end = desc_beg;
3991 
3992         // Figure out how much data we have downloaded for the prebuffer. This will
3993         // be used later to adjust the bits per sample to try.
3994         while (desc_end.start_time_ns != -1 && desc_end.end_time_ns < prebuffered_ns) {
3995             // Prebuffered the entire Cue.
3996             prebuffer_bytes += desc_end.end_offset - desc_end.start_offset;
3997             temp_prebuffer_ns -= desc_end.end_time_ns - desc_end.start_time_ns;
3998             desc_end = get_cue_desc(s, desc_end.end_time_ns, cues_start);
3999         }
4000         if (desc_end.start_time_ns == -1) {
4001             // The prebuffer is larger than the duration.
4002             if (matroska->duration * matroska->time_scale >= prebuffered_ns)
4003               return -1;
4004             bits_per_second = 0.0;
4005         } else {
4006             // The prebuffer ends in the last Cue. Estimate how much data was
4007             // prebuffered.
4008             pre_bytes = desc_end.end_offset - desc_end.start_offset;
4009             pre_ns = desc_end.end_time_ns - desc_end.start_time_ns;
4010             pre_sec = pre_ns / nano_seconds_per_second;
4011             prebuffer_bytes +=
4012                 pre_bytes * ((temp_prebuffer_ns / nano_seconds_per_second) / pre_sec);
4013 
4014             prebuffer = prebuffer_ns / nano_seconds_per_second;
4015 
4016             // Set this to 0.0 in case our prebuffer buffers the entire video.
4017             bits_per_second = 0.0;
4018             do {
4019                 int64_t desc_bytes = desc_end.end_offset - desc_beg.start_offset;
4020                 int64_t desc_ns = desc_end.end_time_ns - desc_beg.start_time_ns;
4021                 double desc_sec = desc_ns / nano_seconds_per_second;
4022                 double calc_bits_per_second = (desc_bytes * 8) / desc_sec;
4023 
4024                 // Drop the bps by the percentage of bytes buffered.
4025                 double percent = (desc_bytes - prebuffer_bytes) / desc_bytes;
4026                 double mod_bits_per_second = calc_bits_per_second * percent;
4027 
4028                 if (prebuffer < desc_sec) {
4029                     double search_sec =
4030                         (double)(matroska->duration * matroska->time_scale) / nano_seconds_per_second;
4031 
4032                     // Add 1 so the bits per second should be a little bit greater than file
4033                     // datarate.
4034                     int64_t bps = (int64_t)(mod_bits_per_second) + 1;
4035                     const double min_buffer = 0.0;
4036                     double buffer = prebuffer;
4037                     double sec_to_download = 0.0;
4038 
4039                     int rv = buffer_size_after_time_downloaded(prebuffered_ns, search_sec, bps,
4040                                                                min_buffer, &buffer, &sec_to_download,
4041                                                                s, cues_start);
4042                     if (rv < 0) {
4043                         return -1;
4044                     } else if (rv == 0) {
4045                         bits_per_second = (double)(bps);
4046                         break;
4047                     }
4048                 }
4049 
4050                 desc_end = get_cue_desc(s, desc_end.end_time_ns, cues_start);
4051             } while (desc_end.start_time_ns != -1);
4052         }
4053         if (bandwidth < bits_per_second) bandwidth = bits_per_second;
4054     }
4055     return (int64_t)bandwidth;
4056 }
4057 
webm_dash_manifest_cues(AVFormatContext * s,int64_t init_range)4058 static int webm_dash_manifest_cues(AVFormatContext *s, int64_t init_range)
4059 {
4060     MatroskaDemuxContext *matroska = s->priv_data;
4061     EbmlList *seekhead_list = &matroska->seekhead;
4062     MatroskaSeekhead *seekhead = seekhead_list->elem;
4063     char *buf;
4064     int64_t cues_start = -1, cues_end = -1, before_pos, bandwidth;
4065     int i;
4066     int end = 0;
4067 
4068     // determine cues start and end positions
4069     for (i = 0; i < seekhead_list->nb_elem; i++)
4070         if (seekhead[i].id == MATROSKA_ID_CUES)
4071             break;
4072 
4073     if (i >= seekhead_list->nb_elem) return -1;
4074 
4075     before_pos = avio_tell(matroska->ctx->pb);
4076     cues_start = seekhead[i].pos + matroska->segment_start;
4077     if (avio_seek(matroska->ctx->pb, cues_start, SEEK_SET) == cues_start) {
4078         // cues_end is computed as cues_start + cues_length + length of the
4079         // Cues element ID (i.e. 4) + EBML length of the Cues element.
4080         // cues_end is inclusive and the above sum is reduced by 1.
4081         uint64_t cues_length, cues_id;
4082         int bytes_read;
4083         bytes_read = ebml_read_num   (matroska, matroska->ctx->pb, 4, &cues_id, 1);
4084         if (bytes_read < 0 || cues_id != (MATROSKA_ID_CUES & 0xfffffff))
4085             return bytes_read < 0 ? bytes_read : AVERROR_INVALIDDATA;
4086         bytes_read = ebml_read_length(matroska, matroska->ctx->pb, &cues_length);
4087         if (bytes_read < 0)
4088             return bytes_read;
4089         cues_end = cues_start + 4 + bytes_read + cues_length - 1;
4090     }
4091     avio_seek(matroska->ctx->pb, before_pos, SEEK_SET);
4092     if (cues_start == -1 || cues_end == -1) return -1;
4093 
4094     // parse the cues
4095     matroska_parse_cues(matroska);
4096 
4097     // cues start
4098     av_dict_set_int(&s->streams[0]->metadata, CUES_START, cues_start, 0);
4099 
4100     // cues end
4101     av_dict_set_int(&s->streams[0]->metadata, CUES_END, cues_end, 0);
4102 
4103     // if the file has cues at the start, fix up the init range so that
4104     // it does not include it
4105     if (cues_start <= init_range)
4106         av_dict_set_int(&s->streams[0]->metadata, INITIALIZATION_RANGE, cues_start - 1, 0);
4107 
4108     // bandwidth
4109     bandwidth = webm_dash_manifest_compute_bandwidth(s, cues_start);
4110     if (bandwidth < 0) return -1;
4111     av_dict_set_int(&s->streams[0]->metadata, BANDWIDTH, bandwidth, 0);
4112 
4113     // check if all clusters start with key frames
4114     av_dict_set_int(&s->streams[0]->metadata, CLUSTER_KEYFRAME, webm_clusters_start_with_keyframe(s), 0);
4115 
4116     // store cue point timestamps as a comma separated list for checking subsegment alignment in
4117     // the muxer. assumes that each timestamp cannot be more than 20 characters long.
4118     buf = av_malloc_array(s->streams[0]->nb_index_entries, 20);
4119     if (!buf) return -1;
4120     strcpy(buf, "");
4121     for (i = 0; i < s->streams[0]->nb_index_entries; i++) {
4122         int ret = snprintf(buf + end, 20,
4123                            "%" PRId64"%s", s->streams[0]->index_entries[i].timestamp,
4124                            i != s->streams[0]->nb_index_entries - 1 ? "," : "");
4125         if (ret <= 0 || (ret == 20 && i ==  s->streams[0]->nb_index_entries - 1)) {
4126             av_log(s, AV_LOG_ERROR, "timestamp too long.\n");
4127             av_free(buf);
4128             return AVERROR_INVALIDDATA;
4129         }
4130         end += ret;
4131     }
4132     av_dict_set(&s->streams[0]->metadata, CUE_TIMESTAMPS,
4133                 buf, AV_DICT_DONT_STRDUP_VAL);
4134 
4135     return 0;
4136 }
4137 
webm_dash_manifest_read_header(AVFormatContext * s)4138 static int webm_dash_manifest_read_header(AVFormatContext *s)
4139 {
4140     char *buf;
4141     int ret = matroska_read_header(s);
4142     int64_t init_range;
4143     MatroskaTrack *tracks;
4144     MatroskaDemuxContext *matroska = s->priv_data;
4145     if (ret) {
4146         av_log(s, AV_LOG_ERROR, "Failed to read file headers\n");
4147         return -1;
4148     }
4149     if (!s->nb_streams) {
4150         matroska_read_close(s);
4151         av_log(s, AV_LOG_ERROR, "No streams found\n");
4152         return AVERROR_INVALIDDATA;
4153     }
4154 
4155     if (!matroska->is_live) {
4156         buf = av_asprintf("%g", matroska->duration);
4157         if (!buf) return AVERROR(ENOMEM);
4158         av_dict_set(&s->streams[0]->metadata, DURATION,
4159                     buf, AV_DICT_DONT_STRDUP_VAL);
4160 
4161         // initialization range
4162         // 5 is the offset of Cluster ID.
4163         init_range = avio_tell(s->pb) - 5;
4164         av_dict_set_int(&s->streams[0]->metadata, INITIALIZATION_RANGE, init_range, 0);
4165     }
4166 
4167     // basename of the file
4168     buf = strrchr(s->url, '/');
4169     av_dict_set(&s->streams[0]->metadata, FILENAME, buf ? ++buf : s->url, 0);
4170 
4171     // track number
4172     tracks = matroska->tracks.elem;
4173     av_dict_set_int(&s->streams[0]->metadata, TRACK_NUMBER, tracks[0].num, 0);
4174 
4175     // parse the cues and populate Cue related fields
4176     if (!matroska->is_live) {
4177         ret = webm_dash_manifest_cues(s, init_range);
4178         if (ret < 0) {
4179             av_log(s, AV_LOG_ERROR, "Error parsing Cues\n");
4180             return ret;
4181         }
4182     }
4183 
4184     // use the bandwidth from the command line if it was provided
4185     if (matroska->bandwidth > 0) {
4186         av_dict_set_int(&s->streams[0]->metadata, BANDWIDTH,
4187                         matroska->bandwidth, 0);
4188     }
4189     return 0;
4190 }
4191 
webm_dash_manifest_read_packet(AVFormatContext * s,AVPacket * pkt)4192 static int webm_dash_manifest_read_packet(AVFormatContext *s, AVPacket *pkt)
4193 {
4194     return AVERROR_EOF;
4195 }
4196 
4197 #define OFFSET(x) offsetof(MatroskaDemuxContext, x)
4198 static const AVOption options[] = {
4199     { "live", "flag indicating that the input is a live file that only has the headers.", OFFSET(is_live), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, AV_OPT_FLAG_DECODING_PARAM },
4200     { "bandwidth", "bandwidth of this stream to be specified in the DASH manifest.", OFFSET(bandwidth), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
4201     { NULL },
4202 };
4203 
4204 static const AVClass webm_dash_class = {
4205     .class_name = "WebM DASH Manifest demuxer",
4206     .item_name  = av_default_item_name,
4207     .option     = options,
4208     .version    = LIBAVUTIL_VERSION_INT,
4209 };
4210 
4211 AVInputFormat ff_matroska_demuxer = {
4212     .name           = "matroska,webm",
4213     .long_name      = NULL_IF_CONFIG_SMALL("Matroska / WebM"),
4214     .extensions     = "mkv,mk3d,mka,mks",
4215     .priv_data_size = sizeof(MatroskaDemuxContext),
4216     .read_probe     = matroska_probe,
4217     .read_header    = matroska_read_header,
4218     .read_packet    = matroska_read_packet,
4219     .read_close     = matroska_read_close,
4220     .read_seek      = matroska_read_seek,
4221     .mime_type      = "audio/webm,audio/x-matroska,video/webm,video/x-matroska"
4222 };
4223 
4224 AVInputFormat ff_webm_dash_manifest_demuxer = {
4225     .name           = "webm_dash_manifest",
4226     .long_name      = NULL_IF_CONFIG_SMALL("WebM DASH Manifest"),
4227     .priv_data_size = sizeof(MatroskaDemuxContext),
4228     .read_header    = webm_dash_manifest_read_header,
4229     .read_packet    = webm_dash_manifest_read_packet,
4230     .read_close     = matroska_read_close,
4231     .priv_class     = &webm_dash_class,
4232 };
4233