id3v2.c
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1 /*
2  * ID3v2 header parser
3  * Copyright (c) 2003 Fabrice Bellard
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "id3v2.h"
23 #include "id3v1.h"
24 #include "libavutil/avstring.h"
25 #include "libavutil/intreadwrite.h"
26 #include "libavutil/dict.h"
27 #include "avio_internal.h"
28 
30  { "TALB", "album"},
31  { "TCOM", "composer"},
32  { "TCON", "genre"},
33  { "TCOP", "copyright"},
34  { "TENC", "encoded_by"},
35  { "TIT2", "title"},
36  { "TLAN", "language"},
37  { "TPE1", "artist"},
38  { "TPE2", "album_artist"},
39  { "TPE3", "performer"},
40  { "TPOS", "disc"},
41  { "TPUB", "publisher"},
42  { "TRCK", "track"},
43  { "TSSE", "encoder"},
44  { 0 }
45 };
46 
48  { "TDRL", "date"},
49  { "TDRC", "date"},
50  { "TDEN", "creation_time"},
51  { "TSOA", "album-sort"},
52  { "TSOP", "artist-sort"},
53  { "TSOT", "title-sort"},
54  { 0 }
55 };
56 
58  { "TAL", "album"},
59  { "TCO", "genre"},
60  { "TT2", "title"},
61  { "TEN", "encoded_by"},
62  { "TP1", "artist"},
63  { "TP2", "album_artist"},
64  { "TP3", "performer"},
65  { "TRK", "track"},
66  { 0 }
67 };
68 
69 
70 const char ff_id3v2_tags[][4] = {
71  "TALB", "TBPM", "TCOM", "TCON", "TCOP", "TDLY", "TENC", "TEXT",
72  "TFLT", "TIT1", "TIT2", "TIT3", "TKEY", "TLAN", "TLEN", "TMED",
73  "TOAL", "TOFN", "TOLY", "TOPE", "TOWN", "TPE1", "TPE2", "TPE3",
74  "TPE4", "TPOS", "TPUB", "TRCK", "TRSN", "TRSO", "TSRC", "TSSE",
75  { 0 },
76 };
77 
78 const char ff_id3v2_4_tags[][4] = {
79  "TDEN", "TDOR", "TDRC", "TDRL", "TDTG", "TIPL", "TMCL", "TMOO",
80  "TPRO", "TSOA", "TSOP", "TSOT", "TSST",
81  { 0 },
82 };
83 
84 const char ff_id3v2_3_tags[][4] = {
85  "TDAT", "TIME", "TORY", "TRDA", "TSIZ", "TYER",
86  { 0 },
87 };
88 
89 int ff_id3v2_match(const uint8_t *buf, const char * magic)
90 {
91  return buf[0] == magic[0] &&
92  buf[1] == magic[1] &&
93  buf[2] == magic[2] &&
94  buf[3] != 0xff &&
95  buf[4] != 0xff &&
96  (buf[6] & 0x80) == 0 &&
97  (buf[7] & 0x80) == 0 &&
98  (buf[8] & 0x80) == 0 &&
99  (buf[9] & 0x80) == 0;
100 }
101 
102 int ff_id3v2_tag_len(const uint8_t * buf)
103 {
104  int len = ((buf[6] & 0x7f) << 21) +
105  ((buf[7] & 0x7f) << 14) +
106  ((buf[8] & 0x7f) << 7) +
107  (buf[9] & 0x7f) +
109  if (buf[5] & 0x10)
110  len += ID3v2_HEADER_SIZE;
111  return len;
112 }
113 
114 static unsigned int get_size(AVIOContext *s, int len)
115 {
116  int v = 0;
117  while (len--)
118  v = (v << 7) + (avio_r8(s) & 0x7F);
119  return v;
120 }
121 
125 static void free_geobtag(void *obj)
126 {
127  ID3v2ExtraMetaGEOB *geob = obj;
128  av_free(geob->mime_type);
129  av_free(geob->file_name);
130  av_free(geob->description);
131  av_free(geob->data);
132  av_free(geob);
133 }
134 
147 static int decode_str(AVFormatContext *s, AVIOContext *pb, int encoding,
148  uint8_t **dst, int *maxread)
149 {
150  int ret;
151  uint8_t tmp;
152  uint32_t ch = 1;
153  int left = *maxread;
154  unsigned int (*get)(AVIOContext*) = avio_rb16;
155  AVIOContext *dynbuf;
156 
157  if ((ret = avio_open_dyn_buf(&dynbuf)) < 0) {
158  av_log(s, AV_LOG_ERROR, "Error opening memory stream\n");
159  return ret;
160  }
161 
162  switch (encoding) {
163 
165  while (left && ch) {
166  ch = avio_r8(pb);
167  PUT_UTF8(ch, tmp, avio_w8(dynbuf, tmp);)
168  left--;
169  }
170  break;
171 
173  if ((left -= 2) < 0) {
174  av_log(s, AV_LOG_ERROR, "Cannot read BOM value, input too short\n");
175  avio_close_dyn_buf(dynbuf, dst);
176  av_freep(dst);
177  return AVERROR_INVALIDDATA;
178  }
179  switch (avio_rb16(pb)) {
180  case 0xfffe:
181  get = avio_rl16;
182  case 0xfeff:
183  break;
184  default:
185  av_log(s, AV_LOG_ERROR, "Incorrect BOM value\n");
186  avio_close_dyn_buf(dynbuf, dst);
187  av_freep(dst);
188  *maxread = left;
189  return AVERROR_INVALIDDATA;
190  }
191  // fall-through
192 
194  while ((left > 1) && ch) {
195  GET_UTF16(ch, ((left -= 2) >= 0 ? get(pb) : 0), break;)
196  PUT_UTF8(ch, tmp, avio_w8(dynbuf, tmp);)
197  }
198  if (left < 0)
199  left += 2; /* did not read last char from pb */
200  break;
201 
202  case ID3v2_ENCODING_UTF8:
203  while (left && ch) {
204  ch = avio_r8(pb);
205  avio_w8(dynbuf, ch);
206  left--;
207  }
208  break;
209  default:
210  av_log(s, AV_LOG_WARNING, "Unknown encoding\n");
211  }
212 
213  if (ch)
214  avio_w8(dynbuf, 0);
215 
216  avio_close_dyn_buf(dynbuf, dst);
217  *maxread = left;
218 
219  return 0;
220 }
221 
225 static void read_ttag(AVFormatContext *s, AVIOContext *pb, int taglen, const char *key)
226 {
227  uint8_t *dst;
228  int encoding, dict_flags = AV_DICT_DONT_OVERWRITE;
229  unsigned genre;
230 
231  if (taglen < 1)
232  return;
233 
234  encoding = avio_r8(pb);
235  taglen--; /* account for encoding type byte */
236 
237  if (decode_str(s, pb, encoding, &dst, &taglen) < 0) {
238  av_log(s, AV_LOG_ERROR, "Error reading frame %s, skipped\n", key);
239  return;
240  }
241 
242  if (!(strcmp(key, "TCON") && strcmp(key, "TCO"))
243  && (sscanf(dst, "(%d)", &genre) == 1 || sscanf(dst, "%d", &genre) == 1)
244  && genre <= ID3v1_GENRE_MAX) {
245  av_freep(&dst);
246  dst = ff_id3v1_genre_str[genre];
247  } else if (!(strcmp(key, "TXXX") && strcmp(key, "TXX"))) {
248  /* dst now contains the key, need to get value */
249  key = dst;
250  if (decode_str(s, pb, encoding, &dst, &taglen) < 0) {
251  av_log(s, AV_LOG_ERROR, "Error reading frame %s, skipped\n", key);
252  av_freep(&key);
253  return;
254  }
256  }
257  else if (*dst)
258  dict_flags |= AV_DICT_DONT_STRDUP_VAL;
259 
260  if (dst)
261  av_dict_set(&s->metadata, key, dst, dict_flags);
262 }
263 
267 static void read_geobtag(AVFormatContext *s, AVIOContext *pb, int taglen, char *tag, ID3v2ExtraMeta **extra_meta)
268 {
269  ID3v2ExtraMetaGEOB *geob_data = NULL;
270  ID3v2ExtraMeta *new_extra = NULL;
271  char encoding;
272  unsigned int len;
273 
274  if (taglen < 1)
275  return;
276 
277  geob_data = av_mallocz(sizeof(ID3v2ExtraMetaGEOB));
278  if (!geob_data) {
279  av_log(s, AV_LOG_ERROR, "Failed to alloc %zu bytes\n", sizeof(ID3v2ExtraMetaGEOB));
280  return;
281  }
282 
283  new_extra = av_mallocz(sizeof(ID3v2ExtraMeta));
284  if (!new_extra) {
285  av_log(s, AV_LOG_ERROR, "Failed to alloc %zu bytes\n", sizeof(ID3v2ExtraMeta));
286  goto fail;
287  }
288 
289  /* read encoding type byte */
290  encoding = avio_r8(pb);
291  taglen--;
292 
293  /* read MIME type (always ISO-8859) */
294  if (decode_str(s, pb, ID3v2_ENCODING_ISO8859, &geob_data->mime_type, &taglen) < 0
295  || taglen <= 0)
296  goto fail;
297 
298  /* read file name */
299  if (decode_str(s, pb, encoding, &geob_data->file_name, &taglen) < 0
300  || taglen <= 0)
301  goto fail;
302 
303  /* read content description */
304  if (decode_str(s, pb, encoding, &geob_data->description, &taglen) < 0
305  || taglen < 0)
306  goto fail;
307 
308  if (taglen) {
309  /* save encapsulated binary data */
310  geob_data->data = av_malloc(taglen);
311  if (!geob_data->data) {
312  av_log(s, AV_LOG_ERROR, "Failed to alloc %d bytes\n", taglen);
313  goto fail;
314  }
315  if ((len = avio_read(pb, geob_data->data, taglen)) < taglen)
316  av_log(s, AV_LOG_WARNING, "Error reading GEOB frame, data truncated.\n");
317  geob_data->datasize = len;
318  } else {
319  geob_data->data = NULL;
320  geob_data->datasize = 0;
321  }
322 
323  /* add data to the list */
324  new_extra->tag = "GEOB";
325  new_extra->data = geob_data;
326  new_extra->next = *extra_meta;
327  *extra_meta = new_extra;
328 
329  return;
330 
331 fail:
332  av_log(s, AV_LOG_ERROR, "Error reading frame %s, skipped\n", tag);
333  free_geobtag(geob_data);
334  av_free(new_extra);
335  return;
336 }
337 
338 static int is_number(const char *str)
339 {
340  while (*str >= '0' && *str <= '9') str++;
341  return !*str;
342 }
343 
345 {
347  if ((t = av_dict_get(m, tag, NULL, AV_DICT_MATCH_CASE)) &&
348  strlen(t->value) == 4 && is_number(t->value))
349  return t;
350  return NULL;
351 }
352 
353 static void merge_date(AVDictionary **m)
354 {
356  char date[17] = {0}; // YYYY-MM-DD hh:mm
357 
358  if (!(t = get_date_tag(*m, "TYER")) &&
359  !(t = get_date_tag(*m, "TYE")))
360  return;
361  av_strlcpy(date, t->value, 5);
362  av_dict_set(m, "TYER", NULL, 0);
363  av_dict_set(m, "TYE", NULL, 0);
364 
365  if (!(t = get_date_tag(*m, "TDAT")) &&
366  !(t = get_date_tag(*m, "TDA")))
367  goto finish;
368  snprintf(date + 4, sizeof(date) - 4, "-%.2s-%.2s", t->value + 2, t->value);
369  av_dict_set(m, "TDAT", NULL, 0);
370  av_dict_set(m, "TDA", NULL, 0);
371 
372  if (!(t = get_date_tag(*m, "TIME")) &&
373  !(t = get_date_tag(*m, "TIM")))
374  goto finish;
375  snprintf(date + 10, sizeof(date) - 10, " %.2s:%.2s", t->value, t->value + 2);
376  av_dict_set(m, "TIME", NULL, 0);
377  av_dict_set(m, "TIM", NULL, 0);
378 
379 finish:
380  if (date[0])
381  av_dict_set(m, "date", date, 0);
382 }
383 
384 typedef struct ID3v2EMFunc {
385  const char *tag3;
386  const char *tag4;
388  void (*free)(void *obj);
389 } ID3v2EMFunc;
390 
392  { "GEO", "GEOB", read_geobtag, free_geobtag },
393  { NULL }
394 };
395 
401 static const ID3v2EMFunc *get_extra_meta_func(const char *tag, int isv34)
402 {
403  int i = 0;
404  while (id3v2_extra_meta_funcs[i].tag3) {
405  if (!memcmp(tag,
406  (isv34 ? id3v2_extra_meta_funcs[i].tag4 :
407  id3v2_extra_meta_funcs[i].tag3),
408  (isv34 ? 4 : 3)))
409  return &id3v2_extra_meta_funcs[i];
410  i++;
411  }
412  return NULL;
413 }
414 
415 static void ff_id3v2_parse(AVFormatContext *s, int len, uint8_t version, uint8_t flags, ID3v2ExtraMeta **extra_meta)
416 {
417  int isv34, tlen, unsync;
418  char tag[5];
419  int64_t next, end = avio_tell(s->pb) + len;
420  int taghdrlen;
421  const char *reason = NULL;
422  AVIOContext pb;
423  AVIOContext *pbx;
424  unsigned char *buffer = NULL;
425  int buffer_size = 0;
426  const ID3v2EMFunc *extra_func;
427 
428  switch (version) {
429  case 2:
430  if (flags & 0x40) {
431  reason = "compression";
432  goto error;
433  }
434  isv34 = 0;
435  taghdrlen = 6;
436  break;
437 
438  case 3:
439  case 4:
440  isv34 = 1;
441  taghdrlen = 10;
442  break;
443 
444  default:
445  reason = "version";
446  goto error;
447  }
448 
449  unsync = flags & 0x80;
450 
451  if (isv34 && flags & 0x40) { /* Extended header present, just skip over it */
452  int extlen = get_size(s->pb, 4);
453  if (version == 4)
454  extlen -= 4; // in v2.4 the length includes the length field we just read
455 
456  if (extlen < 0) {
457  reason = "invalid extended header length";
458  goto error;
459  }
460  avio_skip(s->pb, extlen);
461  }
462 
463  while (len >= taghdrlen) {
464  unsigned int tflags = 0;
465  int tunsync = 0;
466 
467  if (isv34) {
468  avio_read(s->pb, tag, 4);
469  tag[4] = 0;
470  if(version==3){
471  tlen = avio_rb32(s->pb);
472  }else
473  tlen = get_size(s->pb, 4);
474  tflags = avio_rb16(s->pb);
475  tunsync = tflags & ID3v2_FLAG_UNSYNCH;
476  } else {
477  avio_read(s->pb, tag, 3);
478  tag[3] = 0;
479  tlen = avio_rb24(s->pb);
480  }
481  if (tlen < 0 || tlen > len - taghdrlen) {
482  av_log(s, AV_LOG_WARNING, "Invalid size in frame %s, skipping the rest of tag.\n", tag);
483  break;
484  }
485  len -= taghdrlen + tlen;
486  next = avio_tell(s->pb) + tlen;
487 
488  if (!tlen) {
489  if (tag[0])
490  av_log(s, AV_LOG_DEBUG, "Invalid empty frame %s, skipping.\n", tag);
491  continue;
492  }
493 
494  if (tflags & ID3v2_FLAG_DATALEN) {
495  avio_rb32(s->pb);
496  tlen -= 4;
497  }
498 
500  av_log(s, AV_LOG_WARNING, "Skipping encrypted/compressed ID3v2 frame %s.\n", tag);
501  avio_skip(s->pb, tlen);
502  /* check for text tag or supported special meta tag */
503  } else if (tag[0] == 'T' || (extra_meta && (extra_func = get_extra_meta_func(tag, isv34)))) {
504  if (unsync || tunsync) {
505  int64_t end = avio_tell(s->pb) + tlen;
506  uint8_t *b;
507  av_fast_malloc(&buffer, &buffer_size, tlen);
508  if (!buffer) {
509  av_log(s, AV_LOG_ERROR, "Failed to alloc %d bytes\n", tlen);
510  goto seek;
511  }
512  b = buffer;
513  while (avio_tell(s->pb) < end && !s->pb->eof_reached) {
514  *b++ = avio_r8(s->pb);
515  if (*(b - 1) == 0xff && avio_tell(s->pb) < end - 1 &&
516  !s->pb->eof_reached ) {
517  uint8_t val = avio_r8(s->pb);
518  *b++ = val ? val : avio_r8(s->pb);
519  }
520  }
521  ffio_init_context(&pb, buffer, b - buffer, 0, NULL, NULL, NULL, NULL);
522  tlen = b - buffer;
523  pbx = &pb; // read from sync buffer
524  } else {
525  pbx = s->pb; // read straight from input
526  }
527  if (tag[0] == 'T')
528  /* parse text tag */
529  read_ttag(s, pbx, tlen, tag);
530  else
531  /* parse special meta tag */
532  extra_func->read(s, pbx, tlen, tag, extra_meta);
533  }
534  else if (!tag[0]) {
535  if (tag[1])
536  av_log(s, AV_LOG_WARNING, "invalid frame id, assuming padding");
537  avio_skip(s->pb, tlen);
538  break;
539  }
540  /* Skip to end of tag */
541 seek:
542  avio_seek(s->pb, next, SEEK_SET);
543  }
544 
545  if (version == 4 && flags & 0x10) /* Footer preset, always 10 bytes, skip over it */
546  end += 10;
547 
548  error:
549  if (reason)
550  av_log(s, AV_LOG_INFO, "ID3v2.%d tag skipped, cannot handle %s\n", version, reason);
551  avio_seek(s->pb, end, SEEK_SET);
552  av_free(buffer);
553  return;
554 }
555 
556 void ff_id3v2_read_all(AVFormatContext *s, const char *magic, ID3v2ExtraMeta **extra_meta)
557 {
558  int len, ret;
559  uint8_t buf[ID3v2_HEADER_SIZE];
560  int found_header;
561  int64_t off;
562 
563  do {
564  /* save the current offset in case there's nothing to read/skip */
565  off = avio_tell(s->pb);
566  ret = avio_read(s->pb, buf, ID3v2_HEADER_SIZE);
567  if (ret != ID3v2_HEADER_SIZE)
568  break;
569  found_header = ff_id3v2_match(buf, magic);
570  if (found_header) {
571  /* parse ID3v2 header */
572  len = ((buf[6] & 0x7f) << 21) |
573  ((buf[7] & 0x7f) << 14) |
574  ((buf[8] & 0x7f) << 7) |
575  (buf[9] & 0x7f);
576  ff_id3v2_parse(s, len, buf[3], buf[5], extra_meta);
577  } else {
578  avio_seek(s->pb, off, SEEK_SET);
579  }
580  } while (found_header);
581  ff_metadata_conv(&s->metadata, NULL, ff_id3v2_34_metadata_conv);
582  ff_metadata_conv(&s->metadata, NULL, id3v2_2_metadata_conv);
583  ff_metadata_conv(&s->metadata, NULL, ff_id3v2_4_metadata_conv);
584  merge_date(&s->metadata);
585 }
586 
587 void ff_id3v2_read(AVFormatContext *s, const char *magic)
588 {
589  ff_id3v2_read_all(s, magic, NULL);
590 }
591 
593 {
594  ID3v2ExtraMeta *current = *extra_meta, *next;
595  const ID3v2EMFunc *extra_func;
596 
597  while (current) {
598  if ((extra_func = get_extra_meta_func(current->tag, 1)))
599  extra_func->free(current->data);
600  next = current->next;
601  av_freep(&current);
602  current = next;
603  }
604 }