Validate the integrity of the data structure. * when `deep` is 0, only the integrity of the header is validated. * when `deep` is 1, we scan all the entries one by one. */
| 378 | * when `deep` is 0, only the integrity of the header is validated. |
| 379 | * when `deep` is 1, we scan all the entries one by one. */ |
| 380 | int zipmapValidateIntegrity(unsigned char *zm, size_t size, int deep) { |
| 381 | #define OUT_OF_RANGE(p) ( \ |
| 382 | (p) < zm + 2 || \ |
| 383 | (p) > zm + size - 1) |
| 384 | unsigned int l, s, e; |
| 385 | |
| 386 | /* check that we can actually read the header (or ZIPMAP_END). */ |
| 387 | if (size < 2) |
| 388 | return 0; |
| 389 | |
| 390 | /* the last byte must be the terminator. */ |
| 391 | if (zm[size-1] != ZIPMAP_END) |
| 392 | return 0; |
| 393 | |
| 394 | if (!deep) |
| 395 | return 1; |
| 396 | |
| 397 | unsigned int count = 0; |
| 398 | unsigned char *p = zm + 1; /* skip the count */ |
| 399 | while(*p != ZIPMAP_END) { |
| 400 | /* read the field name length encoding type */ |
| 401 | s = zipmapGetEncodedLengthSize(p); |
| 402 | /* make sure the entry length doesn't rech outside the edge of the zipmap */ |
| 403 | if (OUT_OF_RANGE(p+s)) |
| 404 | return 0; |
| 405 | |
| 406 | /* read the field name length */ |
| 407 | l = zipmapDecodeLength(p); |
| 408 | p += s; /* skip the encoded field size */ |
| 409 | p += l; /* skip the field */ |
| 410 | |
| 411 | /* make sure the entry doesn't rech outside the edge of the zipmap */ |
| 412 | if (OUT_OF_RANGE(p)) |
| 413 | return 0; |
| 414 | |
| 415 | /* read the value length encoding type */ |
| 416 | s = zipmapGetEncodedLengthSize(p); |
| 417 | /* make sure the entry length doesn't rech outside the edge of the zipmap */ |
| 418 | if (OUT_OF_RANGE(p+s)) |
| 419 | return 0; |
| 420 | |
| 421 | /* read the value length */ |
| 422 | l = zipmapDecodeLength(p); |
| 423 | p += s; /* skip the encoded value size*/ |
| 424 | e = *p++; /* skip the encoded free space (always encoded in one byte) */ |
| 425 | p += l+e; /* skip the value and free space */ |
| 426 | count++; |
| 427 | |
| 428 | /* make sure the entry doesn't rech outside the edge of the zipmap */ |
| 429 | if (OUT_OF_RANGE(p)) |
| 430 | return 0; |
| 431 | } |
| 432 | |
| 433 | /* check that the zipmap is not empty. */ |
| 434 | if (count == 0) return 0; |
| 435 | |
| 436 | /* check that the count in the header is correct */ |
| 437 | if (zm[0] != ZIPMAP_BIGLEN && zm[0] != count) |
no test coverage detected