facebook
/
zstd
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Modified : ZSTD_createDDict() accepts dictionary < 8 bytes in pure content mode (reported by @chipturner)

dev
Yann Collet 2016-06-19 23:06:54 +02:00
parent a050204342
commit e4811ba761
1 changed files with 17 additions and 21 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

38
lib/decompress/zstd_decompress.c
View File

@ -1179,12 +1179,13 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, c
} }
static void ZSTD_refDictContent(ZSTD_DCtx* dctx, const void* dict, size_t dictSize) static size_t ZSTD_refDictContent(ZSTD_DCtx* dctx, const void* dict, size_t dictSize)
{ {
dctx->dictEnd = dctx->previousDstEnd; dctx->dictEnd = dctx->previousDstEnd;
dctx->vBase = (const char*)dict - ((const char*)(dctx->previousDstEnd) - (const char*)(dctx->base)); dctx->vBase = (const char*)dict - ((const char*)(dctx->previousDstEnd) - (const char*)(dctx->base));
dctx->base = dict; dctx->base = dict;
dctx->previousDstEnd = (const char*)dict + dictSize; dctx->previousDstEnd = (const char*)dict + dictSize;
return 0;
} }
static size_t ZSTD_loadEntropy(ZSTD_DCtx* dctx, const void* const dict, size_t const dictSize) static size_t ZSTD_loadEntropy(ZSTD_DCtx* dctx, const void* const dict, size_t const dictSize)
@ -1236,29 +1237,24 @@ static size_t ZSTD_loadEntropy(ZSTD_DCtx* dctx, const void* const dict, size_t c
static size_t ZSTD_decompress_insertDictionary(ZSTD_DCtx* dctx, const void* dict, size_t dictSize) static size_t ZSTD_decompress_insertDictionary(ZSTD_DCtx* dctx, const void* dict, size_t dictSize)
{ {
if (dictSize < 8) return ERROR(dictionary_corrupted); if (dictSize < 8) return ZSTD_refDictContent(dctx, dict, dictSize);
{ U32 const magic = MEM_readLE32(dict); { U32 const magic = MEM_readLE32(dict);
if (magic != ZSTD_DICT_MAGIC) { if (magic != ZSTD_DICT_MAGIC) {
/* pure content mode */ return ZSTD_refDictContent(dctx, dict, dictSize); /* pure content mode */
ZSTD_refDictContent(dctx, dict, dictSize); } }
return 0; dctx->dictID = MEM_readLE32((const char*)dict + 4);
}
dctx->dictID = MEM_readLE32((const char*)dict + 4);
/* load entropy tables */ /* load entropy tables */
dict = (const char*)dict + 8; dict = (const char*)dict + 8;
dictSize -= 8; dictSize -= 8;
{ size_t const eSize = ZSTD_loadEntropy(dctx, dict, dictSize); { size_t const eSize = ZSTD_loadEntropy(dctx, dict, dictSize);
if (ZSTD_isError(eSize)) return ERROR(dictionary_corrupted); if (ZSTD_isError(eSize)) return ERROR(dictionary_corrupted);
dict = (const char*)dict + eSize; dict = (const char*)dict + eSize;
dictSize -= eSize; dictSize -= eSize;
}
/* reference dictionary content */
ZSTD_refDictContent(dctx, dict, dictSize);
return 0;
} }
/* reference dictionary content */
return ZSTD_refDictContent(dctx, dict, dictSize);
} }
@ -1318,7 +1314,7 @@ ZSTD_DDict* ZSTD_createDDict_advanced(const void* dict, size_t dictSize, ZSTD_cu
} }
/*! ZSTD_createDDict() : /*! ZSTD_createDDict() :
* Create a digested dictionary, ready to start decompression operation without startup delay. * Create a digested dictionary, ready to start decompression without startup delay.
* `dict` can be released after `ZSTD_DDict` creation */ * `dict` can be released after `ZSTD_DDict` creation */
ZSTD_DDict* ZSTD_createDDict(const void* dict, size_t dictSize) ZSTD_DDict* ZSTD_createDDict(const void* dict, size_t dictSize)
{ {