Marco Nelissen | 548dde4 | 2014-01-07 10:11:28 -0800 | [diff] [blame] | 1 | /* exif-mnote-data-canon.c |
| 2 | * |
| 3 | * Copyright (c) 2002, 2003 Lutz Mueller <lutz@users.sourceforge.net> |
| 4 | * Copyright (c) 2003 Matthieu Castet <mat-c@users.sourceforge.net> |
| 5 | * |
| 6 | * This library is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU Lesser General Public |
| 8 | * License as published by the Free Software Foundation; either |
| 9 | * version 2 of the License, or (at your option) any later version. |
| 10 | * |
| 11 | * This library is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 14 | * Lesser General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU Lesser General Public |
| 17 | * License along with this library; if not, write to the |
| 18 | * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, |
| 19 | * Boston, MA 02110-1301 USA. |
| 20 | */ |
| 21 | |
| 22 | #include <config.h> |
| 23 | #include "exif-mnote-data-canon.h" |
| 24 | |
| 25 | #include <stdlib.h> |
| 26 | #include <stdio.h> |
| 27 | #include <string.h> |
| 28 | |
| 29 | #include <libexif/exif-byte-order.h> |
| 30 | #include <libexif/exif-utils.h> |
| 31 | #include <libexif/exif-data.h> |
| 32 | |
| 33 | #define DEBUG |
| 34 | |
| 35 | static void |
| 36 | exif_mnote_data_canon_clear (ExifMnoteDataCanon *n) |
| 37 | { |
| 38 | ExifMnoteData *d = (ExifMnoteData *) n; |
| 39 | unsigned int i; |
| 40 | |
| 41 | if (!n) return; |
| 42 | |
| 43 | if (n->entries) { |
| 44 | for (i = 0; i < n->count; i++) |
| 45 | if (n->entries[i].data) { |
| 46 | exif_mem_free (d->mem, n->entries[i].data); |
| 47 | n->entries[i].data = NULL; |
| 48 | } |
| 49 | exif_mem_free (d->mem, n->entries); |
| 50 | n->entries = NULL; |
| 51 | n->count = 0; |
| 52 | } |
| 53 | } |
| 54 | |
| 55 | static void |
| 56 | exif_mnote_data_canon_free (ExifMnoteData *n) |
| 57 | { |
| 58 | if (!n) return; |
| 59 | |
| 60 | exif_mnote_data_canon_clear ((ExifMnoteDataCanon *) n); |
| 61 | } |
| 62 | |
| 63 | static void |
| 64 | exif_mnote_data_canon_get_tags (ExifMnoteDataCanon *dc, unsigned int n, |
| 65 | unsigned int *m, unsigned int *s) |
| 66 | { |
| 67 | unsigned int from = 0, to; |
| 68 | |
| 69 | if (!dc || !m) return; |
| 70 | for (*m = 0; *m < dc->count; (*m)++) { |
| 71 | to = from + mnote_canon_entry_count_values (&dc->entries[*m]); |
| 72 | if (to > n) { |
| 73 | if (s) *s = n - from; |
| 74 | break; |
| 75 | } |
| 76 | from = to; |
| 77 | } |
| 78 | } |
| 79 | |
| 80 | static char * |
| 81 | exif_mnote_data_canon_get_value (ExifMnoteData *note, unsigned int n, char *val, unsigned int maxlen) |
| 82 | { |
| 83 | ExifMnoteDataCanon *dc = (ExifMnoteDataCanon *) note; |
| 84 | unsigned int m, s; |
| 85 | |
| 86 | if (!dc) return NULL; |
| 87 | exif_mnote_data_canon_get_tags (dc, n, &m, &s); |
| 88 | if (m >= dc->count) return NULL; |
| 89 | return mnote_canon_entry_get_value (&dc->entries[m], s, val, maxlen); |
| 90 | } |
| 91 | |
| 92 | static void |
| 93 | exif_mnote_data_canon_set_byte_order (ExifMnoteData *d, ExifByteOrder o) |
| 94 | { |
| 95 | ExifByteOrder o_orig; |
| 96 | ExifMnoteDataCanon *n = (ExifMnoteDataCanon *) d; |
| 97 | unsigned int i; |
| 98 | |
| 99 | if (!n) return; |
| 100 | |
| 101 | o_orig = n->order; |
| 102 | n->order = o; |
| 103 | for (i = 0; i < n->count; i++) { |
| 104 | n->entries[i].order = o; |
| 105 | exif_array_set_byte_order (n->entries[i].format, n->entries[i].data, |
| 106 | n->entries[i].components, o_orig, o); |
| 107 | } |
| 108 | } |
| 109 | |
| 110 | static void |
| 111 | exif_mnote_data_canon_set_offset (ExifMnoteData *n, unsigned int o) |
| 112 | { |
| 113 | if (n) ((ExifMnoteDataCanon *) n)->offset = o; |
| 114 | } |
| 115 | |
| 116 | static void |
| 117 | exif_mnote_data_canon_save (ExifMnoteData *ne, |
| 118 | unsigned char **buf, unsigned int *buf_size) |
| 119 | { |
| 120 | ExifMnoteDataCanon *n = (ExifMnoteDataCanon *) ne; |
| 121 | size_t i, o, s, doff; |
| 122 | unsigned char *t; |
| 123 | size_t ts; |
| 124 | |
| 125 | if (!n || !buf || !buf_size) return; |
| 126 | |
| 127 | /* |
| 128 | * Allocate enough memory for all entries and the number |
| 129 | * of entries. |
| 130 | */ |
| 131 | *buf_size = 2 + n->count * 12 + 4; |
| 132 | *buf = exif_mem_alloc (ne->mem, sizeof (char) * *buf_size); |
| 133 | if (!*buf) { |
| 134 | EXIF_LOG_NO_MEMORY(ne->log, "ExifMnoteCanon", *buf_size); |
| 135 | return; |
| 136 | } |
| 137 | |
| 138 | /* Save the number of entries */ |
| 139 | exif_set_short (*buf, n->order, (ExifShort) n->count); |
| 140 | |
| 141 | /* Save each entry */ |
| 142 | for (i = 0; i < n->count; i++) { |
| 143 | o = 2 + i * 12; |
| 144 | exif_set_short (*buf + o + 0, n->order, (ExifShort) n->entries[i].tag); |
| 145 | exif_set_short (*buf + o + 2, n->order, (ExifShort) n->entries[i].format); |
| 146 | exif_set_long (*buf + o + 4, n->order, |
| 147 | n->entries[i].components); |
| 148 | o += 8; |
| 149 | s = exif_format_get_size (n->entries[i].format) * |
| 150 | n->entries[i].components; |
| 151 | if (s > 65536) { |
| 152 | /* Corrupt data: EXIF data size is limited to the |
| 153 | * maximum size of a JPEG segment (64 kb). |
| 154 | */ |
| 155 | continue; |
| 156 | } |
| 157 | if (s > 4) { |
| 158 | ts = *buf_size + s; |
| 159 | |
| 160 | /* Ensure even offsets. Set padding bytes to 0. */ |
| 161 | if (s & 1) ts += 1; |
| 162 | t = exif_mem_realloc (ne->mem, *buf, |
| 163 | sizeof (char) * ts); |
| 164 | if (!t) { |
| 165 | EXIF_LOG_NO_MEMORY(ne->log, "ExifMnoteCanon", ts); |
| 166 | return; |
| 167 | } |
| 168 | *buf = t; |
| 169 | *buf_size = ts; |
| 170 | doff = *buf_size - s; |
| 171 | if (s & 1) { doff--; *(*buf + *buf_size - 1) = '\0'; } |
| 172 | exif_set_long (*buf + o, n->order, n->offset + doff); |
| 173 | } else |
| 174 | doff = o; |
| 175 | |
| 176 | /* |
| 177 | * Write the data. Fill unneeded bytes with 0. Do not |
| 178 | * crash if data is NULL. |
| 179 | */ |
| 180 | if (!n->entries[i].data) memset (*buf + doff, 0, s); |
| 181 | else memcpy (*buf + doff, n->entries[i].data, s); |
| 182 | if (s < 4) memset (*buf + doff + s, 0, (4 - s)); |
| 183 | } |
| 184 | } |
| 185 | |
| 186 | /* XXX |
| 187 | * FIXME: exif_mnote_data_canon_load() may fail and there is no |
| 188 | * semantics to express that. |
| 189 | * See bug #1054323 for details, especially the comment by liblit |
| 190 | * after it has supposedly been fixed: |
| 191 | * |
| 192 | * https://sourceforge.net/tracker/?func=detail&aid=1054323&group_id=12272&atid=112272 |
| 193 | * Unfortunately, the "return" statements aren't commented at |
| 194 | * all, so it isn't trivial to find out what is a normal |
| 195 | * return, and what is a reaction to an error condition. |
| 196 | */ |
| 197 | |
| 198 | static void |
| 199 | exif_mnote_data_canon_load (ExifMnoteData *ne, |
| 200 | const unsigned char *buf, unsigned int buf_size) |
| 201 | { |
| 202 | ExifMnoteDataCanon *n = (ExifMnoteDataCanon *) ne; |
| 203 | ExifShort c; |
| 204 | size_t i, tcount, o, datao; |
| 205 | |
| 206 | if (!n || !buf || !buf_size) { |
| 207 | exif_log (ne->log, EXIF_LOG_CODE_CORRUPT_DATA, |
| 208 | "ExifMnoteCanon", "Short MakerNote"); |
| 209 | return; |
| 210 | } |
| 211 | datao = 6 + n->offset; |
| 212 | if ((datao + 2 < datao) || (datao + 2 < 2) || (datao + 2 > buf_size)) { |
| 213 | exif_log (ne->log, EXIF_LOG_CODE_CORRUPT_DATA, |
| 214 | "ExifMnoteCanon", "Short MakerNote"); |
| 215 | return; |
| 216 | } |
| 217 | |
| 218 | /* Read the number of tags */ |
| 219 | c = exif_get_short (buf + datao, n->order); |
| 220 | datao += 2; |
| 221 | |
| 222 | /* Remove any old entries */ |
| 223 | exif_mnote_data_canon_clear (n); |
| 224 | |
| 225 | /* Reserve enough space for all the possible MakerNote tags */ |
| 226 | n->entries = exif_mem_alloc (ne->mem, sizeof (MnoteCanonEntry) * c); |
| 227 | if (!n->entries) { |
| 228 | EXIF_LOG_NO_MEMORY(ne->log, "ExifMnoteCanon", sizeof (MnoteCanonEntry) * c); |
| 229 | return; |
| 230 | } |
| 231 | |
| 232 | /* Parse the entries */ |
| 233 | tcount = 0; |
| 234 | for (i = c, o = datao; i; --i, o += 12) { |
| 235 | size_t s; |
| 236 | if ((o + 12 < o) || (o + 12 < 12) || (o + 12 > buf_size)) { |
| 237 | exif_log (ne->log, EXIF_LOG_CODE_CORRUPT_DATA, |
| 238 | "ExifMnoteCanon", "Short MakerNote"); |
| 239 | break; |
| 240 | } |
| 241 | |
| 242 | n->entries[tcount].tag = exif_get_short (buf + o, n->order); |
| 243 | n->entries[tcount].format = exif_get_short (buf + o + 2, n->order); |
| 244 | n->entries[tcount].components = exif_get_long (buf + o + 4, n->order); |
| 245 | n->entries[tcount].order = n->order; |
| 246 | |
| 247 | exif_log (ne->log, EXIF_LOG_CODE_DEBUG, "ExifMnoteCanon", |
| 248 | "Loading entry 0x%x ('%s')...", n->entries[tcount].tag, |
| 249 | mnote_canon_tag_get_name (n->entries[tcount].tag)); |
| 250 | |
| 251 | /* |
| 252 | * Size? If bigger than 4 bytes, the actual data is not |
| 253 | * in the entry but somewhere else (offset). |
| 254 | */ |
| 255 | s = exif_format_get_size (n->entries[tcount].format) * |
| 256 | n->entries[tcount].components; |
| 257 | n->entries[tcount].size = s; |
| 258 | if (!s) { |
| 259 | exif_log (ne->log, EXIF_LOG_CODE_CORRUPT_DATA, |
| 260 | "ExifMnoteCanon", |
| 261 | "Invalid zero-length tag size"); |
| 262 | continue; |
| 263 | |
| 264 | } else { |
| 265 | size_t dataofs = o + 8; |
| 266 | if (s > 4) dataofs = exif_get_long (buf + dataofs, n->order) + 6; |
| 267 | if ((dataofs + s < s) || (dataofs + s < dataofs) || (dataofs + s > buf_size)) { |
| 268 | exif_log (ne->log, EXIF_LOG_CODE_DEBUG, |
| 269 | "ExifMnoteCanon", |
Mark Salyzyn | fa0c1e7 | 2014-04-18 12:51:18 -0700 | [diff] [blame] | 270 | "Tag data past end of buffer (%zu > %u)", |
Marco Nelissen | 548dde4 | 2014-01-07 10:11:28 -0800 | [diff] [blame] | 271 | dataofs + s, buf_size); |
| 272 | continue; |
| 273 | } |
| 274 | |
| 275 | n->entries[tcount].data = exif_mem_alloc (ne->mem, s); |
| 276 | if (!n->entries[tcount].data) { |
| 277 | EXIF_LOG_NO_MEMORY(ne->log, "ExifMnoteCanon", s); |
| 278 | continue; |
| 279 | } |
| 280 | memcpy (n->entries[tcount].data, buf + dataofs, s); |
| 281 | } |
| 282 | |
| 283 | /* Tag was successfully parsed */ |
| 284 | ++tcount; |
| 285 | } |
| 286 | /* Store the count of successfully parsed tags */ |
| 287 | n->count = tcount; |
| 288 | } |
| 289 | |
| 290 | static unsigned int |
| 291 | exif_mnote_data_canon_count (ExifMnoteData *n) |
| 292 | { |
| 293 | ExifMnoteDataCanon *dc = (ExifMnoteDataCanon *) n; |
| 294 | unsigned int i, c; |
| 295 | |
| 296 | for (i = c = 0; dc && (i < dc->count); i++) |
| 297 | c += mnote_canon_entry_count_values (&dc->entries[i]); |
| 298 | return c; |
| 299 | } |
| 300 | |
| 301 | static unsigned int |
| 302 | exif_mnote_data_canon_get_id (ExifMnoteData *d, unsigned int i) |
| 303 | { |
| 304 | ExifMnoteDataCanon *dc = (ExifMnoteDataCanon *) d; |
| 305 | unsigned int m; |
| 306 | |
| 307 | if (!dc) return 0; |
| 308 | exif_mnote_data_canon_get_tags (dc, i, &m, NULL); |
| 309 | if (m >= dc->count) return 0; |
| 310 | return dc->entries[m].tag; |
| 311 | } |
| 312 | |
| 313 | static const char * |
| 314 | exif_mnote_data_canon_get_name (ExifMnoteData *note, unsigned int i) |
| 315 | { |
| 316 | ExifMnoteDataCanon *dc = (ExifMnoteDataCanon *) note; |
| 317 | unsigned int m, s; |
| 318 | |
| 319 | if (!dc) return NULL; |
| 320 | exif_mnote_data_canon_get_tags (dc, i, &m, &s); |
| 321 | if (m >= dc->count) return NULL; |
| 322 | return mnote_canon_tag_get_name_sub (dc->entries[m].tag, s, dc->options); |
| 323 | } |
| 324 | |
| 325 | static const char * |
| 326 | exif_mnote_data_canon_get_title (ExifMnoteData *note, unsigned int i) |
| 327 | { |
| 328 | ExifMnoteDataCanon *dc = (ExifMnoteDataCanon *) note; |
| 329 | unsigned int m, s; |
| 330 | |
| 331 | if (!dc) return NULL; |
| 332 | exif_mnote_data_canon_get_tags (dc, i, &m, &s); |
| 333 | if (m >= dc->count) return NULL; |
| 334 | return mnote_canon_tag_get_title_sub (dc->entries[m].tag, s, dc->options); |
| 335 | } |
| 336 | |
| 337 | static const char * |
| 338 | exif_mnote_data_canon_get_description (ExifMnoteData *note, unsigned int i) |
| 339 | { |
| 340 | ExifMnoteDataCanon *dc = (ExifMnoteDataCanon *) note; |
| 341 | unsigned int m; |
| 342 | |
| 343 | if (!dc) return NULL; |
| 344 | exif_mnote_data_canon_get_tags (dc, i, &m, NULL); |
| 345 | if (m >= dc->count) return NULL; |
| 346 | return mnote_canon_tag_get_description (dc->entries[m].tag); |
| 347 | } |
| 348 | |
| 349 | int |
| 350 | exif_mnote_data_canon_identify (const ExifData *ed, const ExifEntry *e) |
| 351 | { |
| 352 | char value[8]; |
| 353 | ExifEntry *em = exif_data_get_entry (ed, EXIF_TAG_MAKE); |
| 354 | if (!em) |
| 355 | return 0; |
| 356 | return !strcmp (exif_entry_get_value (em, value, sizeof (value)), "Canon"); |
| 357 | } |
| 358 | |
| 359 | ExifMnoteData * |
| 360 | exif_mnote_data_canon_new (ExifMem *mem, ExifDataOption o) |
| 361 | { |
| 362 | ExifMnoteData *d; |
| 363 | ExifMnoteDataCanon *dc; |
| 364 | |
| 365 | if (!mem) return NULL; |
| 366 | |
| 367 | d = exif_mem_alloc (mem, sizeof (ExifMnoteDataCanon)); |
| 368 | if (!d) |
| 369 | return NULL; |
| 370 | |
| 371 | exif_mnote_data_construct (d, mem); |
| 372 | |
| 373 | /* Set up function pointers */ |
| 374 | d->methods.free = exif_mnote_data_canon_free; |
| 375 | d->methods.set_byte_order = exif_mnote_data_canon_set_byte_order; |
| 376 | d->methods.set_offset = exif_mnote_data_canon_set_offset; |
| 377 | d->methods.load = exif_mnote_data_canon_load; |
| 378 | d->methods.save = exif_mnote_data_canon_save; |
| 379 | d->methods.count = exif_mnote_data_canon_count; |
| 380 | d->methods.get_id = exif_mnote_data_canon_get_id; |
| 381 | d->methods.get_name = exif_mnote_data_canon_get_name; |
| 382 | d->methods.get_title = exif_mnote_data_canon_get_title; |
| 383 | d->methods.get_description = exif_mnote_data_canon_get_description; |
| 384 | d->methods.get_value = exif_mnote_data_canon_get_value; |
| 385 | |
| 386 | dc = (ExifMnoteDataCanon*)d; |
| 387 | dc->options = o; |
| 388 | return d; |
| 389 | } |