diff options
Diffstat (limited to 'contrib/zstd/zstd_decompress.c')
| -rw-r--r-- | contrib/zstd/zstd_decompress.c | 2551 |
1 files changed, 960 insertions, 1591 deletions
diff --git a/contrib/zstd/zstd_decompress.c b/contrib/zstd/zstd_decompress.c index 91518990e..e466647f0 100644 --- a/contrib/zstd/zstd_decompress.c +++ b/contrib/zstd/zstd_decompress.c @@ -1,5 +1,5 @@ /* - * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. + * Copyright (c) 2016-2020, Yann Collet, Facebook, Inc. * All rights reserved. * * This source code is licensed under both the BSD-style license (found in the @@ -14,8 +14,9 @@ *****************************************************************/ /*! * HEAPMODE : - * Select how default decompression function ZSTD_decompress() will allocate memory, - * in memory stack (0), or in memory heap (1, requires malloc()) + * Select how default decompression function ZSTD_decompress() allocates its context, + * on stack (0), or into heap (1, default; requires malloc()). + * Note that functions with explicit context such as ZSTD_decompressDCtx() are unaffected. */ #ifndef ZSTD_HEAPMODE # define ZSTD_HEAPMODE 1 @@ -23,19 +24,31 @@ /*! * LEGACY_SUPPORT : -* if set to 1, ZSTD_decompress() can decode older formats (v0.1+) +* if set to 1+, ZSTD_decompress() can decode older formats (v0.1+) */ #ifndef ZSTD_LEGACY_SUPPORT # define ZSTD_LEGACY_SUPPORT 0 #endif /*! -* MAXWINDOWSIZE_DEFAULT : -* maximum window size accepted by DStream, by default. -* Frames requiring more memory will be rejected. -*/ + * MAXWINDOWSIZE_DEFAULT : + * maximum window size accepted by DStream __by default__. + * Frames requiring more memory will be rejected. + * It's possible to set a different limit using ZSTD_DCtx_setMaxWindowSize(). + */ #ifndef ZSTD_MAXWINDOWSIZE_DEFAULT -# define ZSTD_MAXWINDOWSIZE_DEFAULT ((1 << ZSTD_WINDOWLOG_MAX) + 1) /* defined within zstd.h */ +# define ZSTD_MAXWINDOWSIZE_DEFAULT (((U32)1 << ZSTD_WINDOWLOG_LIMIT_DEFAULT) + 1) +#endif + +/*! + * NO_FORWARD_PROGRESS_MAX : + * maximum allowed nb of calls to ZSTD_decompressStream() + * without any forward progress + * (defined as: no byte read from input, and no byte flushed to output) + * before triggering an error. + */ +#ifndef ZSTD_NO_FORWARD_PROGRESS_MAX +# define ZSTD_NO_FORWARD_PROGRESS_MAX 16 #endif @@ -43,102 +56,25 @@ * Dependencies *********************************************************/ #include <string.h> /* memcpy, memmove, memset */ +#include "cpu.h" /* bmi2 */ #include "mem.h" /* low level memory routines */ #define FSE_STATIC_LINKING_ONLY #include "fse.h" #define HUF_STATIC_LINKING_ONLY #include "huf.h" -#include "zstd_internal.h" +#include "zstd_internal.h" /* blockProperties_t */ +#include "zstd_decompress_internal.h" /* ZSTD_DCtx */ +#include "zstd_ddict.h" /* ZSTD_DDictDictContent */ +#include "zstd_decompress_block.h" /* ZSTD_decompressBlock_internal */ #if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT>=1) -# include "zstd_legacy.h" +# include "../legacy/zstd_legacy.h" #endif -/*-************************************* -* Errors -***************************************/ -#define ZSTD_isError ERR_isError /* for inlining */ -#define FSE_isError ERR_isError -#define HUF_isError ERR_isError - - -/*_******************************************************* -* Memory operations -**********************************************************/ -static void ZSTD_copy4(void* dst, const void* src) { memcpy(dst, src, 4); } - - /*-************************************************************* * Context management ***************************************************************/ -typedef enum { ZSTDds_getFrameHeaderSize, ZSTDds_decodeFrameHeader, - ZSTDds_decodeBlockHeader, ZSTDds_decompressBlock, - ZSTDds_decompressLastBlock, ZSTDds_checkChecksum, - ZSTDds_decodeSkippableHeader, ZSTDds_skipFrame } ZSTD_dStage; - -typedef enum { zdss_init=0, zdss_loadHeader, - zdss_read, zdss_load, zdss_flush } ZSTD_dStreamStage; - -typedef struct { - FSE_DTable LLTable[FSE_DTABLE_SIZE_U32(LLFSELog)]; - FSE_DTable OFTable[FSE_DTABLE_SIZE_U32(OffFSELog)]; - FSE_DTable MLTable[FSE_DTABLE_SIZE_U32(MLFSELog)]; - HUF_DTable hufTable[HUF_DTABLE_SIZE(HufLog)]; /* can accommodate HUF_decompress4X */ - U32 workspace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32]; - U32 rep[ZSTD_REP_NUM]; -} ZSTD_entropyDTables_t; - -struct ZSTD_DCtx_s -{ - const FSE_DTable* LLTptr; - const FSE_DTable* MLTptr; - const FSE_DTable* OFTptr; - const HUF_DTable* HUFptr; - ZSTD_entropyDTables_t entropy; - const void* previousDstEnd; /* detect continuity */ - const void* base; /* start of current segment */ - const void* vBase; /* virtual start of previous segment if it was just before current one */ - const void* dictEnd; /* end of previous segment */ - size_t expected; - ZSTD_frameHeader fParams; - U64 decodedSize; - blockType_e bType; /* used in ZSTD_decompressContinue(), store blockType between block header decoding and block decompression stages */ - ZSTD_dStage stage; - U32 litEntropy; - U32 fseEntropy; - XXH64_state_t xxhState; - size_t headerSize; - U32 dictID; - const BYTE* litPtr; - ZSTD_customMem customMem; - size_t litSize; - size_t rleSize; - size_t staticSize; - - /* streaming */ - ZSTD_DDict* ddictLocal; - const ZSTD_DDict* ddict; - ZSTD_dStreamStage streamStage; - char* inBuff; - size_t inBuffSize; - size_t inPos; - size_t maxWindowSize; - char* outBuff; - size_t outBuffSize; - size_t outStart; - size_t outEnd; - size_t lhSize; - void* legacyContext; - U32 previousLegacyVersion; - U32 legacyVersion; - U32 hostageByte; - - /* workspace */ - BYTE litBuffer[ZSTD_BLOCKSIZE_MAX + WILDCOPY_OVERLENGTH]; - BYTE headerBuffer[ZSTD_FRAMEHEADERSIZE_MAX]; -}; /* typedef'd to ZSTD_DCtx within "zstd.h" */ - size_t ZSTD_sizeof_DCtx (const ZSTD_DCtx* dctx) { if (dctx==NULL) return 0; /* support sizeof NULL */ @@ -149,38 +85,51 @@ size_t ZSTD_sizeof_DCtx (const ZSTD_DCtx* dctx) size_t ZSTD_estimateDCtxSize(void) { return sizeof(ZSTD_DCtx); } -size_t ZSTD_decompressBegin(ZSTD_DCtx* dctx) + +static size_t ZSTD_startingInputLength(ZSTD_format_e format) { - dctx->expected = ZSTD_frameHeaderSize_prefix; - dctx->stage = ZSTDds_getFrameHeaderSize; - dctx->decodedSize = 0; - dctx->previousDstEnd = NULL; - dctx->base = NULL; - dctx->vBase = NULL; - dctx->dictEnd = NULL; - dctx->entropy.hufTable[0] = (HUF_DTable)((HufLog)*0x1000001); /* cover both little and big endian */ - dctx->litEntropy = dctx->fseEntropy = 0; - dctx->dictID = 0; - MEM_STATIC_ASSERT(sizeof(dctx->entropy.rep) == sizeof(repStartValue)); - memcpy(dctx->entropy.rep, repStartValue, sizeof(repStartValue)); /* initial repcodes */ - dctx->LLTptr = dctx->entropy.LLTable; - dctx->MLTptr = dctx->entropy.MLTable; - dctx->OFTptr = dctx->entropy.OFTable; - dctx->HUFptr = dctx->entropy.hufTable; - return 0; + size_t const startingInputLength = ZSTD_FRAMEHEADERSIZE_PREFIX(format); + /* only supports formats ZSTD_f_zstd1 and ZSTD_f_zstd1_magicless */ + assert( (format == ZSTD_f_zstd1) || (format == ZSTD_f_zstd1_magicless) ); + return startingInputLength; } static void ZSTD_initDCtx_internal(ZSTD_DCtx* dctx) { - ZSTD_decompressBegin(dctx); /* cannot fail */ + dctx->format = ZSTD_f_zstd1; /* ZSTD_decompressBegin() invokes ZSTD_startingInputLength() with argument dctx->format */ dctx->staticSize = 0; dctx->maxWindowSize = ZSTD_MAXWINDOWSIZE_DEFAULT; dctx->ddict = NULL; dctx->ddictLocal = NULL; + dctx->dictEnd = NULL; + dctx->ddictIsCold = 0; + dctx->dictUses = ZSTD_dont_use; dctx->inBuff = NULL; dctx->inBuffSize = 0; dctx->outBuffSize = 0; dctx->streamStage = zdss_init; + dctx->legacyContext = NULL; + dctx->previousLegacyVersion = 0; + dctx->noForwardProgress = 0; + dctx->oversizedDuration = 0; + dctx->bmi2 = ZSTD_cpuid_bmi2(ZSTD_cpuid()); + dctx->outBufferMode = ZSTD_obm_buffered; +#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION + dctx->dictContentEndForFuzzing = NULL; +#endif +} + +ZSTD_DCtx* ZSTD_initStaticDCtx(void *workspace, size_t workspaceSize) +{ + ZSTD_DCtx* const dctx = (ZSTD_DCtx*) workspace; + + if ((size_t)workspace & 7) return NULL; /* 8-aligned */ + if (workspaceSize < sizeof(ZSTD_DCtx)) return NULL; /* minimum size */ + + ZSTD_initDCtx_internal(dctx); + dctx->staticSize = workspaceSize; + dctx->inBuff = (char*)(dctx+1); + return dctx; } ZSTD_DCtx* ZSTD_createDCtx_advanced(ZSTD_customMem customMem) @@ -190,38 +139,31 @@ ZSTD_DCtx* ZSTD_createDCtx_advanced(ZSTD_customMem customMem) { ZSTD_DCtx* const dctx = (ZSTD_DCtx*)ZSTD_malloc(sizeof(*dctx), customMem); if (!dctx) return NULL; dctx->customMem = customMem; - dctx->legacyContext = NULL; - dctx->previousLegacyVersion = 0; ZSTD_initDCtx_internal(dctx); return dctx; } } -ZSTD_DCtx* ZSTD_initStaticDCtx(void *workspace, size_t workspaceSize) +ZSTD_DCtx* ZSTD_createDCtx(void) { - ZSTD_DCtx* dctx = (ZSTD_DCtx*) workspace; - - if ((size_t)workspace & 7) return NULL; /* 8-aligned */ - if (workspaceSize < sizeof(ZSTD_DCtx)) return NULL; /* minimum size */ - - ZSTD_initDCtx_internal(dctx); - dctx->staticSize = workspaceSize; - dctx->inBuff = (char*)(dctx+1); - return dctx; + DEBUGLOG(3, "ZSTD_createDCtx"); + return ZSTD_createDCtx_advanced(ZSTD_defaultCMem); } -ZSTD_DCtx* ZSTD_createDCtx(void) +static void ZSTD_clearDict(ZSTD_DCtx* dctx) { - return ZSTD_createDCtx_advanced(ZSTD_defaultCMem); + ZSTD_freeDDict(dctx->ddictLocal); + dctx->ddictLocal = NULL; + dctx->ddict = NULL; + dctx->dictUses = ZSTD_dont_use; } size_t ZSTD_freeDCtx(ZSTD_DCtx* dctx) { if (dctx==NULL) return 0; /* support free on NULL */ - if (dctx->staticSize) return ERROR(memory_allocation); /* not compatible with static DCtx */ + RETURN_ERROR_IF(dctx->staticSize, memory_allocation, "not compatible with static DCtx"); { ZSTD_customMem const cMem = dctx->customMem; - ZSTD_freeDDict(dctx->ddictLocal); - dctx->ddictLocal = NULL; + ZSTD_clearDict(dctx); ZSTD_free(dctx->inBuff, cMem); dctx->inBuff = NULL; #if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT >= 1) @@ -242,8 +184,8 @@ void ZSTD_copyDCtx(ZSTD_DCtx* dstDCtx, const ZSTD_DCtx* srcDCtx) /*-************************************************************* -* Decompression section -***************************************************************/ + * Frame header decoding + ***************************************************************/ /*! ZSTD_isFrame() : * Tells if the content of `buffer` starts with a valid Frame Identifier. @@ -252,10 +194,10 @@ void ZSTD_copyDCtx(ZSTD_DCtx* dstDCtx, const ZSTD_DCtx* srcDCtx) * Note 3 : Skippable Frame Identifiers are considered valid. */ unsigned ZSTD_isFrame(const void* buffer, size_t size) { - if (size < 4) return 0; + if (size < ZSTD_FRAMEIDSIZE) return 0; { U32 const magic = MEM_readLE32(buffer); if (magic == ZSTD_MAGICNUMBER) return 1; - if ((magic & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) return 1; + if ((magic & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) return 1; } #if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT >= 1) if (ZSTD_isLegacy(buffer, size)) return 1; @@ -263,54 +205,73 @@ unsigned ZSTD_isFrame(const void* buffer, size_t size) return 0; } - -/** ZSTD_frameHeaderSize() : -* srcSize must be >= ZSTD_frameHeaderSize_prefix. -* @return : size of the Frame Header */ -size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize) +/** ZSTD_frameHeaderSize_internal() : + * srcSize must be large enough to reach header size fields. + * note : only works for formats ZSTD_f_zstd1 and ZSTD_f_zstd1_magicless. + * @return : size of the Frame Header + * or an error code, which can be tested with ZSTD_isError() */ +static size_t ZSTD_frameHeaderSize_internal(const void* src, size_t srcSize, ZSTD_format_e format) { - if (srcSize < ZSTD_frameHeaderSize_prefix) return ERROR(srcSize_wrong); - { BYTE const fhd = ((const BYTE*)src)[4]; + size_t const minInputSize = ZSTD_startingInputLength(format); + RETURN_ERROR_IF(srcSize < minInputSize, srcSize_wrong, ""); + + { BYTE const fhd = ((const BYTE*)src)[minInputSize-1]; U32 const dictID= fhd & 3; U32 const singleSegment = (fhd >> 5) & 1; U32 const fcsId = fhd >> 6; - return ZSTD_frameHeaderSize_prefix + !singleSegment + ZSTD_did_fieldSize[dictID] + ZSTD_fcs_fieldSize[fcsId] - + (singleSegment && !fcsId); + return minInputSize + !singleSegment + + ZSTD_did_fieldSize[dictID] + ZSTD_fcs_fieldSize[fcsId] + + (singleSegment && !fcsId); } } +/** ZSTD_frameHeaderSize() : + * srcSize must be >= ZSTD_frameHeaderSize_prefix. + * @return : size of the Frame Header, + * or an error code (if srcSize is too small) */ +size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize) +{ + return ZSTD_frameHeaderSize_internal(src, srcSize, ZSTD_f_zstd1); +} -/** ZSTD_getFrameHeader() : -* decode Frame Header, or require larger `srcSize`. -* @return : 0, `zfhPtr` is correctly filled, -* >0, `srcSize` is too small, result is expected `srcSize`, -* or an error code, which can be tested using ZSTD_isError() */ -size_t ZSTD_getFrameHeader(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize) + +/** ZSTD_getFrameHeader_advanced() : + * decode Frame Header, or require larger `srcSize`. + * note : only works for formats ZSTD_f_zstd1 and ZSTD_f_zstd1_magicless + * @return : 0, `zfhPtr` is correctly filled, + * >0, `srcSize` is too small, value is wanted `srcSize` amount, + * or an error code, which can be tested using ZSTD_isError() */ +size_t ZSTD_getFrameHeader_advanced(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize, ZSTD_format_e format) { const BYTE* ip = (const BYTE*)src; - if (srcSize < ZSTD_frameHeaderSize_prefix) return ZSTD_frameHeaderSize_prefix; + size_t const minInputSize = ZSTD_startingInputLength(format); + + memset(zfhPtr, 0, sizeof(*zfhPtr)); /* not strictly necessary, but static analyzer do not understand that zfhPtr is only going to be read only if return value is zero, since they are 2 different signals */ + if (srcSize < minInputSize) return minInputSize; + RETURN_ERROR_IF(src==NULL, GENERIC, "invalid parameter"); - if (MEM_readLE32(src) != ZSTD_MAGICNUMBER) { - if ((MEM_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { + if ( (format != ZSTD_f_zstd1_magicless) + && (MEM_readLE32(src) != ZSTD_MAGICNUMBER) ) { + if ((MEM_readLE32(src) & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) { /* skippable frame */ - if (srcSize < ZSTD_skippableHeaderSize) - return ZSTD_skippableHeaderSize; /* magic number + frame length */ + if (srcSize < ZSTD_SKIPPABLEHEADERSIZE) + return ZSTD_SKIPPABLEHEADERSIZE; /* magic number + frame length */ memset(zfhPtr, 0, sizeof(*zfhPtr)); - zfhPtr->frameContentSize = MEM_readLE32((const char *)src + 4); + zfhPtr->frameContentSize = MEM_readLE32((const char *)src + ZSTD_FRAMEIDSIZE); zfhPtr->frameType = ZSTD_skippableFrame; return 0; } - return ERROR(prefix_unknown); + RETURN_ERROR(prefix_unknown, ""); } /* ensure there is enough `srcSize` to fully read/decode frame header */ - { size_t const fhsize = ZSTD_frameHeaderSize(src, srcSize); + { size_t const fhsize = ZSTD_frameHeaderSize_internal(src, srcSize, format); if (srcSize < fhsize) return fhsize; zfhPtr->headerSize = (U32)fhsize; } - { BYTE const fhdByte = ip[4]; - size_t pos = 5; + { BYTE const fhdByte = ip[minInputSize-1]; + size_t pos = minInputSize; U32 const dictIDSizeCode = fhdByte&3; U32 const checksumFlag = (fhdByte>>2)&1; U32 const singleSegment = (fhdByte>>5)&1; @@ -318,14 +279,13 @@ size_t ZSTD_getFrameHeader(ZSTD_frameHeader* zfhPtr, const void* src, size_t src U64 windowSize = 0; U32 dictID = 0; U64 frameContentSize = ZSTD_CONTENTSIZE_UNKNOWN; - if ((fhdByte & 0x08) != 0) - return ERROR(frameParameter_unsupported); /* reserved bits, must be zero */ + RETURN_ERROR_IF((fhdByte & 0x08) != 0, frameParameter_unsupported, + "reserved bits, must be zero"); if (!singleSegment) { BYTE const wlByte = ip[pos++]; U32 const windowLog = (wlByte >> 3) + ZSTD_WINDOWLOG_ABSOLUTEMIN; - if (windowLog > ZSTD_WINDOWLOG_MAX) - return ERROR(frameParameter_windowTooLarge); + RETURN_ERROR_IF(windowLog > ZSTD_WINDOWLOG_MAX, frameParameter_windowTooLarge, ""); windowSize = (1ULL << windowLog); windowSize += (windowSize >> 3) * (wlByte&7); } @@ -357,6 +317,18 @@ size_t ZSTD_getFrameHeader(ZSTD_frameHeader* zfhPtr, const void* src, size_t src return 0; } +/** ZSTD_getFrameHeader() : + * decode Frame Header, or require larger `srcSize`. + * note : this function does not consume input, it only reads it. + * @return : 0, `zfhPtr` is correctly filled, + * >0, `srcSize` is too small, value is wanted `srcSize` amount, + * or an error code, which can be tested using ZSTD_isError() */ +size_t ZSTD_getFrameHeader(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize) +{ + return ZSTD_getFrameHeader_advanced(zfhPtr, src, srcSize, ZSTD_f_zstd1); +} + + /** ZSTD_getFrameContentSize() : * compatible with legacy mode * @return : decompressed size of the single frame pointed to be `src` if known, otherwise @@ -380,6 +352,23 @@ unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize) } } } +static size_t readSkippableFrameSize(void const* src, size_t srcSize) +{ + size_t const skippableHeaderSize = ZSTD_SKIPPABLEHEADERSIZE; + U32 sizeU32; + + RETURN_ERROR_IF(srcSize < ZSTD_SKIPPABLEHEADERSIZE, srcSize_wrong, ""); + + sizeU32 = MEM_readLE32((BYTE const*)src + ZSTD_FRAMEIDSIZE); + RETURN_ERROR_IF((U32)(sizeU32 + ZSTD_SKIPPABLEHEADERSIZE) < sizeU32, + frameParameter_unsupported, ""); + { + size_t const skippableSize = skippableHeaderSize + sizeU32; + RETURN_ERROR_IF(skippableSize > srcSize, srcSize_wrong, ""); + return skippableSize; + } +} + /** ZSTD_findDecompressedSize() : * compatible with legacy mode * `srcSize` must be the exact length of some number of ZSTD compressed and/or @@ -389,18 +378,15 @@ unsigned long long ZSTD_findDecompressedSize(const void* src, size_t srcSize) { unsigned long long totalDstSize = 0; - while (srcSize >= ZSTD_frameHeaderSize_prefix) { - const U32 magicNumber = MEM_readLE32(src); + while (srcSize >= ZSTD_startingInputLength(ZSTD_f_zstd1)) { + U32 const magicNumber = MEM_readLE32(src); - if ((magicNumber & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { - size_t skippableSize; - if (srcSize < ZSTD_skippableHeaderSize) - return ERROR(srcSize_wrong); - skippableSize = MEM_readLE32((const BYTE *)src + 4) + - ZSTD_skippableHeaderSize; - if (srcSize < skippableSize) { + if ((magicNumber & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) { + size_t const skippableSize = readSkippableFrameSize(src, srcSize); + if (ZSTD_isError(skippableSize)) { return ZSTD_CONTENTSIZE_ERROR; } + assert(skippableSize <= srcSize); src = (const BYTE *)src + skippableSize; srcSize -= skippableSize; @@ -422,19 +408,17 @@ unsigned long long ZSTD_findDecompressedSize(const void* src, size_t srcSize) src = (const BYTE *)src + frameSrcSize; srcSize -= frameSrcSize; } - } + } /* while (srcSize >= ZSTD_frameHeaderSize_prefix) */ - if (srcSize) { - return ZSTD_CONTENTSIZE_ERROR; - } + if (srcSize) return ZSTD_CONTENTSIZE_ERROR; return totalDstSize; } /** ZSTD_getDecompressedSize() : -* compatible with legacy mode -* @return : decompressed size if known, 0 otherwise - note : 0 can mean any of the following : + * compatible with legacy mode + * @return : decompressed size if known, 0 otherwise + note : 0 can mean any of the following : - frame content is empty - decompressed size field is not present in frame header - frame header unknown / not supported @@ -442,1084 +426,223 @@ unsigned long long ZSTD_findDecompressedSize(const void* src, size_t srcSize) unsigned long long ZSTD_getDecompressedSize(const void* src, size_t srcSize) { unsigned long long const ret = ZSTD_getFrameContentSize(src, srcSize); - return ret >= ZSTD_CONTENTSIZE_ERROR ? 0 : ret; + ZSTD_STATIC_ASSERT(ZSTD_CONTENTSIZE_ERROR < ZSTD_CONTENTSIZE_UNKNOWN); + return (ret >= ZSTD_CONTENTSIZE_ERROR) ? 0 : ret; } /** ZSTD_decodeFrameHeader() : -* `headerSize` must be the size provided by ZSTD_frameHeaderSize(). -* @return : 0 if success, or an error code, which can be tested using ZSTD_isError() */ + * `headerSize` must be the size provided by ZSTD_frameHeaderSize(). + * @return : 0 if success, or an error code, which can be tested using ZSTD_isError() */ static size_t ZSTD_decodeFrameHeader(ZSTD_DCtx* dctx, const void* src, size_t headerSize) { - size_t const result = ZSTD_getFrameHeader(&(dctx->fParams), src, headerSize); - if (ZSTD_isError(result)) return result; /* invalid header */ - if (result>0) return ERROR(srcSize_wrong); /* headerSize too small */ - if (dctx->fParams.dictID && (dctx->dictID != dctx->fParams.dictID)) - return ERROR(dictionary_wrong); + size_t const result = ZSTD_getFrameHeader_advanced(&(dctx->fParams), src, headerSize, dctx->format); + if (ZSTD_isError(result)) return result; /* invalid header */ + RETURN_ERROR_IF(result>0, srcSize_wrong, "headerSize too small"); +#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION + /* Skip the dictID check in fuzzing mode, because it makes the search + * harder. + */ + RETURN_ERROR_IF(dctx->fParams.dictID && (dctx->dictID != dctx->fParams.dictID), + dictionary_wrong, ""); +#endif if (dctx->fParams.checksumFlag) XXH64_reset(&dctx->xxhState, 0); return 0; } - -/*! ZSTD_getcBlockSize() : -* Provides the size of compressed block from block header `src` */ -size_t ZSTD_getcBlockSize(const void* src, size_t srcSize, - blockProperties_t* bpPtr) -{ - if (srcSize < ZSTD_blockHeaderSize) return ERROR(srcSize_wrong); - { U32 const cBlockHeader = MEM_readLE24(src); - U32 const cSize = cBlockHeader >> 3; - bpPtr->lastBlock = cBlockHeader & 1; - bpPtr->blockType = (blockType_e)((cBlockHeader >> 1) & 3); - bpPtr->origSize = cSize; /* only useful for RLE */ - if (bpPtr->blockType == bt_rle) return 1; - if (bpPtr->blockType == bt_reserved) return ERROR(corruption_detected); - return cSize; - } -} - - -static size_t ZSTD_copyRawBlock(void* dst, size_t dstCapacity, - const void* src, size_t srcSize) -{ - if (srcSize > dstCapacity) return ERROR(dstSize_tooSmall); - memcpy(dst, src, srcSize); - return srcSize; -} - - -static size_t ZSTD_setRleBlock(void* dst, size_t dstCapacity, - const void* src, size_t srcSize, - size_t regenSize) -{ - if (srcSize != 1) return ERROR(srcSize_wrong); - if (regenSize > dstCapacity) return ERROR(dstSize_tooSmall); - memset(dst, *(const BYTE*)src, regenSize); - return regenSize; -} - -/*! ZSTD_decodeLiteralsBlock() : - @return : nb of bytes read from src (< srcSize ) */ -size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx, - const void* src, size_t srcSize) /* note : srcSize < BLOCKSIZE */ +static ZSTD_frameSizeInfo ZSTD_errorFrameSizeInfo(size_t ret) { - if (srcSize < MIN_CBLOCK_SIZE) return ERROR(corruption_detected); - - { const BYTE* const istart = (const BYTE*) src; - symbolEncodingType_e const litEncType = (symbolEncodingType_e)(istart[0] & 3); - - switch(litEncType) - { - case set_repeat: - if (dctx->litEntropy==0) return ERROR(dictionary_corrupted); - /* fall-through */ - case set_compressed: - if (srcSize < 5) return ERROR(corruption_detected); /* srcSize >= MIN_CBLOCK_SIZE == 3; here we need up to 5 for case 3 */ - { size_t lhSize, litSize, litCSize; - U32 singleStream=0; - U32 const lhlCode = (istart[0] >> 2) & 3; - U32 const lhc = MEM_readLE32(istart); - switch(lhlCode) - { - case 0: case 1: default: /* note : default is impossible, since lhlCode into [0..3] */ - /* 2 - 2 - 10 - 10 */ - singleStream = !lhlCode; - lhSize = 3; - litSize = (lhc >> 4) & 0x3FF; - litCSize = (lhc >> 14) & 0x3FF; - break; - case 2: - /* 2 - 2 - 14 - 14 */ - lhSize = 4; - litSize = (lhc >> 4) & 0x3FFF; - litCSize = lhc >> 18; - break; - case 3: - /* 2 - 2 - 18 - 18 */ - lhSize = 5; - litSize = (lhc >> 4) & 0x3FFFF; - litCSize = (lhc >> 22) + (istart[4] << 10); - break; - } - if (litSize > ZSTD_BLOCKSIZE_MAX) return ERROR(corruption_detected); - if (litCSize + lhSize > srcSize) return ERROR(corruption_detected); - - if (HUF_isError((litEncType==set_repeat) ? - ( singleStream ? - HUF_decompress1X_usingDTable(dctx->litBuffer, litSize, istart+lhSize, litCSize, dctx->HUFptr) : - HUF_decompress4X_usingDTable(dctx->litBuffer, litSize, istart+lhSize, litCSize, dctx->HUFptr) ) : - ( singleStream ? - HUF_decompress1X2_DCtx_wksp(dctx->entropy.hufTable, dctx->litBuffer, litSize, istart+lhSize, litCSize, - dctx->entropy.workspace, sizeof(dctx->entropy.workspace)) : - HUF_decompress4X_hufOnly_wksp(dctx->entropy.hufTable, dctx->litBuffer, litSize, istart+lhSize, litCSize, - dctx->entropy.workspace, sizeof(dctx->entropy.workspace))))) - return ERROR(corruption_detected); - - dctx->litPtr = dctx->litBuffer; - dctx->litSize = litSize; - dctx->litEntropy = 1; - if (litEncType==set_compressed) dctx->HUFptr = dctx->entropy.hufTable; - memset(dctx->litBuffer + dctx->litSize, 0, WILDCOPY_OVERLENGTH); - return litCSize + lhSize; - } - - case set_basic: - { size_t litSize, lhSize; - U32 const lhlCode = ((istart[0]) >> 2) & 3; - switch(lhlCode) - { - case 0: case 2: default: /* note : default is impossible, since lhlCode into [0..3] */ - lhSize = 1; - litSize = istart[0] >> 3; - break; - case 1: - lhSize = 2; - litSize = MEM_readLE16(istart) >> 4; - break; - case 3: - lhSize = 3; - litSize = MEM_readLE24(istart) >> 4; - break; - } - - if (lhSize+litSize+WILDCOPY_OVERLENGTH > srcSize) { /* risk reading beyond src buffer with wildcopy */ - if (litSize+lhSize > srcSize) return ERROR(corruption_detected); - memcpy(dctx->litBuffer, istart+lhSize, litSize); - dctx->litPtr = dctx->litBuffer; - dctx->litSize = litSize; - memset(dctx->litBuffer + dctx->litSize, 0, WILDCOPY_OVERLENGTH); - return lhSize+litSize; - } - /* direct reference into compressed stream */ - dctx->litPtr = istart+lhSize; - dctx->litSize = litSize; - return lhSize+litSize; - } - - case set_rle: - { U32 const lhlCode = ((istart[0]) >> 2) & 3; - size_t litSize, lhSize; - switch(lhlCode) - { - case 0: case 2: default: /* note : default is impossible, since lhlCode into [0..3] */ - lhSize = 1; - litSize = istart[0] >> 3; - break; - case 1: - lhSize = 2; - litSize = MEM_readLE16(istart) >> 4; - break; - case 3: - lhSize = 3; - litSize = MEM_readLE24(istart) >> 4; - if (srcSize<4) return ERROR(corruption_detected); /* srcSize >= MIN_CBLOCK_SIZE == 3; here we need lhSize+1 = 4 */ - break; - } - if (litSize > ZSTD_BLOCKSIZE_MAX) return ERROR(corruption_detected); - memset(dctx->litBuffer, istart[lhSize], litSize + WILDCOPY_OVERLENGTH); - dctx->litPtr = dctx->litBuffer; - dctx->litSize = litSize; - return lhSize+1; - } - default: - return ERROR(corruption_detected); /* impossible */ - } - } + ZSTD_frameSizeInfo frameSizeInfo; + frameSizeInfo.compressedSize = ret; + frameSizeInfo.decompressedBound = ZSTD_CONTENTSIZE_ERROR; + return frameSizeInfo; } - -typedef union { - FSE_decode_t realData; - U32 alignedBy4; -} FSE_decode_t4; - -/* Default FSE distribution table for Literal Lengths */ -static const FSE_decode_t4 LL_defaultDTable[(1<<LL_DEFAULTNORMLOG)+1] = { - { { LL_DEFAULTNORMLOG, 1, 1 } }, /* header : tableLog, fastMode, fastMode */ - /* base, symbol, bits */ - { { 0, 0, 4 } }, { { 16, 0, 4 } }, { { 32, 1, 5 } }, { { 0, 3, 5 } }, - { { 0, 4, 5 } }, { { 0, 6, 5 } }, { { 0, 7, 5 } }, { { 0, 9, 5 } }, - { { 0, 10, 5 } }, { { 0, 12, 5 } }, { { 0, 14, 6 } }, { { 0, 16, 5 } }, - { { 0, 18, 5 } }, { { 0, 19, 5 } }, { { 0, 21, 5 } }, { { 0, 22, 5 } }, - { { 0, 24, 5 } }, { { 32, 25, 5 } }, { { 0, 26, 5 } }, { { 0, 27, 6 } }, - { { 0, 29, 6 } }, { { 0, 31, 6 } }, { { 32, 0, 4 } }, { { 0, 1, 4 } }, - { { 0, 2, 5 } }, { { 32, 4, 5 } }, { { 0, 5, 5 } }, { { 32, 7, 5 } }, - { { 0, 8, 5 } }, { { 32, 10, 5 } }, { { 0, 11, 5 } }, { { 0, 13, 6 } }, - { { 32, 16, 5 } }, { { 0, 17, 5 } }, { { 32, 19, 5 } }, { { 0, 20, 5 } }, - { { 32, 22, 5 } }, { { 0, 23, 5 } }, { { 0, 25, 4 } }, { { 16, 25, 4 } }, - { { 32, 26, 5 } }, { { 0, 28, 6 } }, { { 0, 30, 6 } }, { { 48, 0, 4 } }, - { { 16, 1, 4 } }, { { 32, 2, 5 } }, { { 32, 3, 5 } }, { { 32, 5, 5 } }, - { { 32, 6, 5 } }, { { 32, 8, 5 } }, { { 32, 9, 5 } }, { { 32, 11, 5 } }, - { { 32, 12, 5 } }, { { 0, 15, 6 } }, { { 32, 17, 5 } }, { { 32, 18, 5 } }, - { { 32, 20, 5 } }, { { 32, 21, 5 } }, { { 32, 23, 5 } }, { { 32, 24, 5 } }, - { { 0, 35, 6 } }, { { 0, 34, 6 } }, { { 0, 33, 6 } }, { { 0, 32, 6 } }, -}; /* LL_defaultDTable */ - -/* Default FSE distribution table for Match Lengths */ -static const FSE_decode_t4 ML_defaultDTable[(1<<ML_DEFAULTNORMLOG)+1] = { - { { ML_DEFAULTNORMLOG, 1, 1 } }, /* header : tableLog, fastMode, fastMode */ - /* base, symbol, bits */ - { { 0, 0, 6 } }, { { 0, 1, 4 } }, { { 32, 2, 5 } }, { { 0, 3, 5 } }, - { { 0, 5, 5 } }, { { 0, 6, 5 } }, { { 0, 8, 5 } }, { { 0, 10, 6 } }, - { { 0, 13, 6 } }, { { 0, 16, 6 } }, { { 0, 19, 6 } }, { { 0, 22, 6 } }, - { { 0, 25, 6 } }, { { 0, 28, 6 } }, { { 0, 31, 6 } }, { { 0, 33, 6 } }, - { { 0, 35, 6 } }, { { 0, 37, 6 } }, { { 0, 39, 6 } }, { { 0, 41, 6 } }, - { { 0, 43, 6 } }, { { 0, 45, 6 } }, { { 16, 1, 4 } }, { { 0, 2, 4 } }, - { { 32, 3, 5 } }, { { 0, 4, 5 } }, { { 32, 6, 5 } }, { { 0, 7, 5 } }, - { { 0, 9, 6 } }, { { 0, 12, 6 } }, { { 0, 15, 6 } }, { { 0, 18, 6 } }, - { { 0, 21, 6 } }, { { 0, 24, 6 } }, { { 0, 27, 6 } }, { { 0, 30, 6 } }, - { { 0, 32, 6 } }, { { 0, 34, 6 } }, { { 0, 36, 6 } }, { { 0, 38, 6 } }, - { { 0, 40, 6 } }, { { 0, 42, 6 } }, { { 0, 44, 6 } }, { { 32, 1, 4 } }, - { { 48, 1, 4 } }, { { 16, 2, 4 } }, { { 32, 4, 5 } }, { { 32, 5, 5 } }, - { { 32, 7, 5 } }, { { 32, 8, 5 } }, { { 0, 11, 6 } }, { { 0, 14, 6 } }, - { { 0, 17, 6 } }, { { 0, 20, 6 } }, { { 0, 23, 6 } }, { { 0, 26, 6 } }, - { { 0, 29, 6 } }, { { 0, 52, 6 } }, { { 0, 51, 6 } }, { { 0, 50, 6 } }, - { { 0, 49, 6 } }, { { 0, 48, 6 } }, { { 0, 47, 6 } }, { { 0, 46, 6 } }, -}; /* ML_defaultDTable */ - -/* Default FSE distribution table for Offset Codes */ -static const FSE_decode_t4 OF_defaultDTable[(1<<OF_DEFAULTNORMLOG)+1] = { - { { OF_DEFAULTNORMLOG, 1, 1 } }, /* header : tableLog, fastMode, fastMode */ - /* base, symbol, bits */ - { { 0, 0, 5 } }, { { 0, 6, 4 } }, - { { 0, 9, 5 } }, { { 0, 15, 5 } }, - { { 0, 21, 5 } }, { { 0, 3, 5 } }, - { { 0, 7, 4 } }, { { 0, 12, 5 } }, - { { 0, 18, 5 } }, { { 0, 23, 5 } }, - { { 0, 5, 5 } }, { { 0, 8, 4 } }, - { { 0, 14, 5 } }, { { 0, 20, 5 } }, - { { 0, 2, 5 } }, { { 16, 7, 4 } }, - { { 0, 11, 5 } }, { { 0, 17, 5 } }, - { { 0, 22, 5 } }, { { 0, 4, 5 } }, - { { 16, 8, 4 } }, { { 0, 13, 5 } }, - { { 0, 19, 5 } }, { { 0, 1, 5 } }, - { { 16, 6, 4 } }, { { 0, 10, 5 } }, - { { 0, 16, 5 } }, { { 0, 28, 5 } }, - { { 0, 27, 5 } }, { { 0, 26, 5 } }, - { { 0, 25, 5 } }, { { 0, 24, 5 } }, -}; /* OF_defaultDTable */ - -/*! ZSTD_buildSeqTable() : - @return : nb bytes read from src, - or an error code if it fails, testable with ZSTD_isError() -*/ -static size_t ZSTD_buildSeqTable(FSE_DTable* DTableSpace, const FSE_DTable** DTablePtr, - symbolEncodingType_e type, U32 max, U32 maxLog, - const void* src, size_t srcSize, - const FSE_decode_t4* defaultTable, U32 flagRepeatTable) +static ZSTD_frameSizeInfo ZSTD_findFrameSizeInfo(const void* src, size_t srcSize) { - const void* const tmpPtr = defaultTable; /* bypass strict aliasing */ - switch(type) - { - case set_rle : - if (!srcSize) return ERROR(srcSize_wrong); - if ( (*(const BYTE*)src) > max) return ERROR(corruption_detected); - FSE_buildDTable_rle(DTableSpace, *(const BYTE*)src); - *DTablePtr = DTableSpace; - return 1; - case set_basic : - *DTablePtr = (const FSE_DTable*)tmpPtr; - return 0; - case set_repeat: - if (!flagRepeatTable) return ERROR(corruption_detected); - return 0; - default : /* impossible */ - case set_compressed : - { U32 tableLog; - S16 norm[MaxSeq+1]; - size_t const headerSize = FSE_readNCount(norm, &max, &tableLog, src, srcSize); - if (FSE_isError(headerSize)) return ERROR(corruption_detected); - if (tableLog > maxLog) return ERROR(corruption_detected); - FSE_buildDTable(DTableSpace, norm, max, tableLog); - *DTablePtr = DTableSpace; - return headerSize; - } } -} + ZSTD_frameSizeInfo frameSizeInfo; + memset(&frameSizeInfo, 0, sizeof(ZSTD_frameSizeInfo)); -size_t ZSTD_decodeSeqHeaders(ZSTD_DCtx* dctx, int* nbSeqPtr, - const void* src, size_t srcSize) -{ - const BYTE* const istart = (const BYTE* const)src; - const BYTE* const iend = istart + srcSize; - const BYTE* ip = istart; - DEBUGLOG(5, "ZSTD_decodeSeqHeaders"); - - /* check */ - if (srcSize < MIN_SEQUENCES_SIZE) return ERROR(srcSize_wrong); - - /* SeqHead */ - { int nbSeq = *ip++; - if (!nbSeq) { *nbSeqPtr=0; return 1; } - if (nbSeq > 0x7F) { - if (nbSeq == 0xFF) { - if (ip+2 > iend) return ERROR(srcSize_wrong); - nbSeq = MEM_readLE16(ip) + LONGNBSEQ, ip+=2; - } else { - if (ip >= iend) return ERROR(srcSize_wrong); - nbSeq = ((nbSeq-0x80)<<8) + *ip++; - } - } - *nbSeqPtr = nbSeq; - } - - /* FSE table descriptors */ - if (ip+4 > iend) return ERROR(srcSize_wrong); /* minimum possible size */ - { symbolEncodingType_e const LLtype = (symbolEncodingType_e)(*ip >> 6); - symbolEncodingType_e const OFtype = (symbolEncodingType_e)((*ip >> 4) & 3); - symbolEncodingType_e const MLtype = (symbolEncodingType_e)((*ip >> 2) & 3); - ip++; - - /* Build DTables */ - { size_t const llhSize = ZSTD_buildSeqTable(dctx->entropy.LLTable, &dctx->LLTptr, - LLtype, MaxLL, LLFSELog, - ip, iend-ip, LL_defaultDTable, dctx->fseEntropy); - if (ZSTD_isError(llhSize)) return ERROR(corruption_detected); - ip += llhSize; - } - { size_t const ofhSize = ZSTD_buildSeqTable(dctx->entropy.OFTable, &dctx->OFTptr, - OFtype, MaxOff, OffFSELog, - ip, iend-ip, OF_defaultDTable, dctx->fseEntropy); - if (ZSTD_isError(ofhSize)) return ERROR(corruption_detected); - ip += ofhSize; - } - { size_t const mlhSize = ZSTD_buildSeqTable(dctx->entropy.MLTable, &dctx->MLTptr, - MLtype, MaxML, MLFSELog, - ip, iend-ip, ML_defaultDTable, dctx->fseEntropy); - if (ZSTD_isError(mlhSize)) return ERROR(corruption_detected); - ip += mlhSize; - } - } - - return ip-istart; -} - - -typedef struct { - size_t litLength; - size_t matchLength; - size_t offset; - const BYTE* match; -} seq_t; - -typedef struct { - BIT_DStream_t DStream; - FSE_DState_t stateLL; - FSE_DState_t stateOffb; - FSE_DState_t stateML; - size_t prevOffset[ZSTD_REP_NUM]; - const BYTE* base; - size_t pos; - uPtrDiff gotoDict; -} seqState_t; - - -FORCE_NOINLINE -size_t ZSTD_execSequenceLast7(BYTE* op, - BYTE* const oend, seq_t sequence, - const BYTE** litPtr, const BYTE* const litLimit, - const BYTE* const base, const BYTE* const vBase, const BYTE* const dictEnd) -{ - BYTE* const oLitEnd = op + sequence.litLength; - size_t const sequenceLength = sequence.litLength + sequence.matchLength; - BYTE* const oMatchEnd = op + sequenceLength; /* risk : address space overflow (32-bits) */ - BYTE* const oend_w = oend - WILDCOPY_OVERLENGTH; - const BYTE* const iLitEnd = *litPtr + sequence.litLength; - const BYTE* match = oLitEnd - sequence.offset; - - /* check */ - if (oMatchEnd>oend) return ERROR(dstSize_tooSmall); /* last match must start at a minimum distance of WILDCOPY_OVERLENGTH from oend */ - if (iLitEnd > litLimit) return ERROR(corruption_detected); /* over-read beyond lit buffer */ - if (oLitEnd <= oend_w) return ERROR(GENERIC); /* Precondition */ - - /* copy literals */ - if (op < oend_w) { - ZSTD_wildcopy(op, *litPtr, oend_w - op); - *litPtr += oend_w - op; - op = oend_w; - } - while (op < oLitEnd) *op++ = *(*litPtr)++; - - /* copy Match */ - if (sequence.offset > (size_t)(oLitEnd - base)) { - /* offset beyond prefix */ - if (sequence.offset > (size_t)(oLitEnd - vBase)) return ERROR(corruption_detected); - match = dictEnd - (base-match); - if (match + sequence.matchLength <= dictEnd) { - memmove(oLitEnd, match, sequence.matchLength); - return sequenceLength; - } - /* span extDict & currentPrefixSegment */ - { size_t const length1 = dictEnd - match; - memmove(oLitEnd, match, length1); - op = oLitEnd + length1; - sequence.matchLength -= length1; - match = base; - } } - while (op < oMatchEnd) *op++ = *match++; - return sequenceLength; -} - - -typedef enum { ZSTD_lo_isRegularOffset, ZSTD_lo_isLongOffset=1 } ZSTD_longOffset_e; - - -static seq_t ZSTD_decodeSequence(seqState_t* seqState, const ZSTD_longOffset_e longOffsets) -{ - seq_t seq; - - U32 const llCode = FSE_peekSymbol(&seqState->stateLL); - U32 const mlCode = FSE_peekSymbol(&seqState->stateML); - U32 const ofCode = FSE_peekSymbol(&seqState->stateOffb); /* <= maxOff, by table construction */ - - U32 const llBits = LL_bits[llCode]; - U32 const mlBits = ML_bits[mlCode]; - U32 const ofBits = ofCode; - U32 const totalBits = llBits+mlBits+ofBits; - - static const U32 LL_base[MaxLL+1] = { - 0, 1, 2, 3, 4, 5, 6, 7, - 8, 9, 10, 11, 12, 13, 14, 15, - 16, 18, 20, 22, 24, 28, 32, 40, - 48, 64, 0x80, 0x100, 0x200, 0x400, 0x800, 0x1000, - 0x2000, 0x4000, 0x8000, 0x10000 }; - - static const U32 ML_base[MaxML+1] = { - 3, 4, 5, 6, 7, 8, 9, 10, - 11, 12, 13, 14, 15, 16, 17, 18, - 19, 20, 21, 22, 23, 24, 25, 26, - 27, 28, 29, 30, 31, 32, 33, 34, - 35, 37, 39, 41, 43, 47, 51, 59, - 67, 83, 99, 0x83, 0x103, 0x203, 0x403, 0x803, - 0x1003, 0x2003, 0x4003, 0x8003, 0x10003 }; - - static const U32 OF_base[MaxOff+1] = { - 0, 1, 1, 5, 0xD, 0x1D, 0x3D, 0x7D, - 0xFD, 0x1FD, 0x3FD, 0x7FD, 0xFFD, 0x1FFD, 0x3FFD, 0x7FFD, - 0xFFFD, 0x1FFFD, 0x3FFFD, 0x7FFFD, 0xFFFFD, 0x1FFFFD, 0x3FFFFD, 0x7FFFFD, - 0xFFFFFD, 0x1FFFFFD, 0x3FFFFFD, 0x7FFFFFD, 0xFFFFFFD }; - - /* sequence */ - { size_t offset; - if (!ofCode) - offset = 0; - else { - ZSTD_STATIC_ASSERT(ZSTD_lo_isLongOffset == 1); - if (longOffsets) { - int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN); - offset = OF_base[ofCode] + (BIT_readBitsFast(&seqState->DStream, ofBits - extraBits) << extraBits); - if (MEM_32bits() || extraBits) BIT_reloadDStream(&seqState->DStream); - if (extraBits) offset += BIT_readBitsFast(&seqState->DStream, extraBits); - } else { - offset = OF_base[ofCode] + BIT_readBitsFast(&seqState->DStream, ofBits); /* <= (ZSTD_WINDOWLOG_MAX-1) bits */ - if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream); - } - } - - if (ofCode <= 1) { - offset += (llCode==0); - if (offset) { - size_t temp = (offset==3) ? seqState->prevOffset[0] - 1 : seqState->prevOffset[offset]; - temp += !temp; /* 0 is not valid; input is corrupted; force offset to 1 */ - if (offset != 1) seqState->prevOffset[2] = seqState->prevOffset[1]; - seqState->prevOffset[1] = seqState->prevOffset[0]; - seqState->prevOffset[0] = offset = temp; - } else { - offset = seqState->prevOffset[0]; - } - } else { - seqState->prevOffset[2] = seqState->prevOffset[1]; - seqState->prevOffset[1] = seqState->prevOffset[0]; - seqState->prevOffset[0] = offset; - } - seq.offset = offset; - } - - seq.matchLength = ML_base[mlCode] - + ((mlCode>31) ? BIT_readBitsFast(&seqState->DStream, mlBits) : 0); /* <= 16 bits */ - if (MEM_32bits() && (mlBits+llBits>24)) BIT_reloadDStream(&seqState->DStream); - - seq.litLength = LL_base[llCode] - + ((llCode>15) ? BIT_readBitsFast(&seqState->DStream, llBits) : 0); /* <= 16 bits */ - if ( MEM_32bits() - || (totalBits > 64 - 7 - (LLFSELog+MLFSELog+OffFSELog)) ) - BIT_reloadDStream(&seqState->DStream); - - DEBUGLOG(6, "seq: litL=%u, matchL=%u, offset=%u", - (U32)seq.litLength, (U32)seq.matchLength, (U32)seq.offset); - - /* ANS state update */ - FSE_updateState(&seqState->stateLL, &seqState->DStream); /* <= 9 bits */ - FSE_updateState(&seqState->stateML, &seqState->DStream); /* <= 9 bits */ - if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream); /* <= 18 bits */ - FSE_updateState(&seqState->stateOffb, &seqState->DStream); /* <= 8 bits */ - - return seq; -} - - -HINT_INLINE -size_t ZSTD_execSequence(BYTE* op, - BYTE* const oend, seq_t sequence, - const BYTE** litPtr, const BYTE* const litLimit, - const BYTE* const base, const BYTE* const vBase, const BYTE* const dictEnd) -{ - BYTE* const oLitEnd = op + sequence.litLength; - size_t const sequenceLength = sequence.litLength + sequence.matchLength; - BYTE* const oMatchEnd = op + sequenceLength; /* risk : address space overflow (32-bits) */ - BYTE* const oend_w = oend - WILDCOPY_OVERLENGTH; - const BYTE* const iLitEnd = *litPtr + sequence.litLength; - const BYTE* match = oLitEnd - sequence.offset; +#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT >= 1) + if (ZSTD_isLegacy(src, srcSize)) + return ZSTD_findFrameSizeInfoLegacy(src, srcSize); +#endif - /* check */ - if (oMatchEnd>oend) return ERROR(dstSize_tooSmall); /* last match must start at a minimum distance of WILDCOPY_OVERLENGTH from oend */ - if (iLitEnd > litLimit) return ERROR(corruption_detected); /* over-read beyond lit buffer */ - if (oLitEnd>oend_w) return ZSTD_execSequenceLast7(op, oend, sequence, litPtr, litLimit, base, vBase, dictEnd); - - /* copy Literals */ - ZSTD_copy8(op, *litPtr); - if (sequence.litLength > 8) - ZSTD_wildcopy(op+8, (*litPtr)+8, sequence.litLength - 8); /* note : since oLitEnd <= oend-WILDCOPY_OVERLENGTH, no risk of overwrite beyond oend */ - op = oLitEnd; - *litPtr = iLitEnd; /* update for next sequence */ - - /* copy Match */ - if (sequence.offset > (size_t)(oLitEnd - base)) { - /* offset beyond prefix -> go into extDict */ - if (sequence.offset > (size_t)(oLitEnd - vBase)) - return ERROR(corruption_detected); - match = dictEnd + (match - base); - if (match + sequence.matchLength <= dictEnd) { - memmove(oLitEnd, match, sequence.matchLength); - return sequenceLength; - } - /* span extDict & currentPrefixSegment */ - { size_t const length1 = dictEnd - match; - memmove(oLitEnd, match, length1); - op = oLitEnd + length1; - sequence.matchLength -= length1; - match = base; - if (op > oend_w || sequence.matchLength < MINMATCH) { - U32 i; - for (i = 0; i < sequence.matchLength; ++i) op[i] = match[i]; - return sequenceLength; - } - } } - /* Requirement: op <= oend_w && sequence.matchLength >= MINMATCH */ - - /* match within prefix */ - if (sequence.offset < 8) { - /* close range match, overlap */ - static const U32 dec32table[] = { 0, 1, 2, 1, 4, 4, 4, 4 }; /* added */ - static const int dec64table[] = { 8, 8, 8, 7, 8, 9,10,11 }; /* subtracted */ - int const sub2 = dec64table[sequence.offset]; - op[0] = match[0]; - op[1] = match[1]; - op[2] = match[2]; - op[3] = match[3]; - match += dec32table[sequence.offset]; - ZSTD_copy4(op+4, match); - match -= sub2; + if ((srcSize >= ZSTD_SKIPPABLEHEADERSIZE) + && (MEM_readLE32(src) & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) { + frameSizeInfo.compressedSize = readSkippableFrameSize(src, srcSize); + assert(ZSTD_isError(frameSizeInfo.compressedSize) || + frameSizeInfo.compressedSize <= srcSize); + return frameSizeInfo; } else { - ZSTD_copy8(op, match); - } - op += 8; match += 8; + const BYTE* ip = (const BYTE*)src; + const BYTE* const ipstart = ip; + size_t remainingSize = srcSize; + size_t nbBlocks = 0; + ZSTD_frameHeader zfh; - if (oMatchEnd > oend-(16-MINMATCH)) { - if (op < oend_w) { - ZSTD_wildcopy(op, match, oend_w - op); - match += oend_w - op; - op = oend_w; + /* Extract Frame Header */ + { size_t const ret = ZSTD_getFrameHeader(&zfh, src, srcSize); + if (ZSTD_isError(ret)) + return ZSTD_errorFrameSizeInfo(ret); + if (ret > 0) + return ZSTD_errorFrameSizeInfo(ERROR(srcSize_wrong)); } - while (op < oMatchEnd) *op++ = *match++; - } else { - ZSTD_wildcopy(op, match, (ptrdiff_t)sequence.matchLength-8); /* works even if matchLength < 8 */ - } - return sequenceLength; -} - - -static size_t ZSTD_decompressSequences( - ZSTD_DCtx* dctx, - void* dst, size_t maxDstSize, - const void* seqStart, size_t seqSize, - const ZSTD_longOffset_e isLongOffset) -{ - const BYTE* ip = (const BYTE*)seqStart; - const BYTE* const iend = ip + seqSize; - BYTE* const ostart = (BYTE* const)dst; - BYTE* const oend = ostart + maxDstSize; - BYTE* op = ostart; - const BYTE* litPtr = dctx->litPtr; - const BYTE* const litEnd = litPtr + dctx->litSize; - const BYTE* const base = (const BYTE*) (dctx->base); - const BYTE* const vBase = (const BYTE*) (dctx->vBase); - const BYTE* const dictEnd = (const BYTE*) (dctx->dictEnd); - int nbSeq; - DEBUGLOG(5, "ZSTD_decompressSequences"); - - /* Build Decoding Tables */ - { size_t const seqHSize = ZSTD_decodeSeqHeaders(dctx, &nbSeq, ip, seqSize); - DEBUGLOG(5, "ZSTD_decodeSeqHeaders: size=%u, nbSeq=%i", - (U32)seqHSize, nbSeq); - if (ZSTD_isError(seqHSize)) return seqHSize; - ip += seqHSize; - } - - /* Regen sequences */ - if (nbSeq) { - seqState_t seqState; - dctx->fseEntropy = 1; - { U32 i; for (i=0; i<ZSTD_REP_NUM; i++) seqState.prevOffset[i] = dctx->entropy.rep[i]; } - CHECK_E(BIT_initDStream(&seqState.DStream, ip, iend-ip), corruption_detected); - FSE_initDState(&seqState.stateLL, &seqState.DStream, dctx->LLTptr); - FSE_initDState(&seqState.stateOffb, &seqState.DStream, dctx->OFTptr); - FSE_initDState(&seqState.stateML, &seqState.DStream, dctx->MLTptr); - - for ( ; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && nbSeq ; ) { - nbSeq--; - { seq_t const sequence = ZSTD_decodeSequence(&seqState, isLongOffset); - size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequence, &litPtr, litEnd, base, vBase, dictEnd); - DEBUGLOG(6, "regenerated sequence size : %u", (U32)oneSeqSize); - if (ZSTD_isError(oneSeqSize)) return oneSeqSize; - op += oneSeqSize; - } } - /* check if reached exact end */ - DEBUGLOG(5, "after decode loop, remaining nbSeq : %i", nbSeq); - if (nbSeq) return ERROR(corruption_detected); - /* save reps for next block */ - { U32 i; for (i=0; i<ZSTD_REP_NUM; i++) dctx->entropy.rep[i] = (U32)(seqState.prevOffset[i]); } - } - - /* last literal segment */ - { size_t const lastLLSize = litEnd - litPtr; - if (lastLLSize > (size_t)(oend-op)) return ERROR(dstSize_tooSmall); - memcpy(op, litPtr, lastLLSize); - op += lastLLSize; - } - - return op-ostart; -} + ip += zfh.headerSize; + remainingSize -= zfh.headerSize; + /* Iterate over each block */ + while (1) { + blockProperties_t blockProperties; + size_t const cBlockSize = ZSTD_getcBlockSize(ip, remainingSize, &blockProperties); + if (ZSTD_isError(cBlockSize)) + return ZSTD_errorFrameSizeInfo(cBlockSize); + if (ZSTD_blockHeaderSize + cBlockSize > remainingSize) + return ZSTD_errorFrameSizeInfo(ERROR(srcSize_wrong)); -HINT_INLINE -seq_t ZSTD_decodeSequenceLong(seqState_t* seqState, ZSTD_longOffset_e const longOffsets) -{ - seq_t seq; - - U32 const llCode = FSE_peekSymbol(&seqState->stateLL); - U32 const mlCode = FSE_peekSymbol(&seqState->stateML); - U32 const ofCode = FSE_peekSymbol(&seqState->stateOffb); /* <= maxOff, by table construction */ - - U32 const llBits = LL_bits[llCode]; - U32 const mlBits = ML_bits[mlCode]; - U32 const ofBits = ofCode; - U32 const totalBits = llBits+mlBits+ofBits; - - static const U32 LL_base[MaxLL+1] = { - 0, 1, 2, 3, 4, 5, 6, 7, - 8, 9, 10, 11, 12, 13, 14, 15, - 16, 18, 20, 22, 24, 28, 32, 40, - 48, 64, 0x80, 0x100, 0x200, 0x400, 0x800, 0x1000, - 0x2000, 0x4000, 0x8000, 0x10000 }; - - static const U32 ML_base[MaxML+1] = { - 3, 4, 5, 6, 7, 8, 9, 10, - 11, 12, 13, 14, 15, 16, 17, 18, - 19, 20, 21, 22, 23, 24, 25, 26, - 27, 28, 29, 30, 31, 32, 33, 34, - 35, 37, 39, 41, 43, 47, 51, 59, - 67, 83, 99, 0x83, 0x103, 0x203, 0x403, 0x803, - 0x1003, 0x2003, 0x4003, 0x8003, 0x10003 }; - - static const U32 OF_base[MaxOff+1] = { - 0, 1, 1, 5, 0xD, 0x1D, 0x3D, 0x7D, - 0xFD, 0x1FD, 0x3FD, 0x7FD, 0xFFD, 0x1FFD, 0x3FFD, 0x7FFD, - 0xFFFD, 0x1FFFD, 0x3FFFD, 0x7FFFD, 0xFFFFD, 0x1FFFFD, 0x3FFFFD, 0x7FFFFD, - 0xFFFFFD, 0x1FFFFFD, 0x3FFFFFD, 0x7FFFFFD, 0xFFFFFFD }; - - /* sequence */ - { size_t offset; - if (!ofCode) - offset = 0; - else { - ZSTD_STATIC_ASSERT(ZSTD_lo_isLongOffset == 1); - if (longOffsets) { - int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN); - offset = OF_base[ofCode] + (BIT_readBitsFast(&seqState->DStream, ofBits - extraBits) << extraBits); - if (MEM_32bits() || extraBits) BIT_reloadDStream(&seqState->DStream); - if (extraBits) offset += BIT_readBitsFast(&seqState->DStream, extraBits); - } else { - offset = OF_base[ofCode] + BIT_readBitsFast(&seqState->DStream, ofBits); /* <= (ZSTD_WINDOWLOG_MAX-1) bits */ - if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream); - } - } + ip += ZSTD_blockHeaderSize + cBlockSize; + remainingSize -= ZSTD_blockHeaderSize + cBlockSize; + nbBlocks++; - if (ofCode <= 1) { - offset += (llCode==0); - if (offset) { - size_t temp = (offset==3) ? seqState->prevOffset[0] - 1 : seqState->prevOffset[offset]; - temp += !temp; /* 0 is not valid; input is corrupted; force offset to 1 */ - if (offset != 1) seqState->prevOffset[2] = seqState->prevOffset[1]; - seqState->prevOffset[1] = seqState->prevOffset[0]; - seqState->prevOffset[0] = offset = temp; - } else { - offset = seqState->prevOffset[0]; - } - } else { - seqState->prevOffset[2] = seqState->prevOffset[1]; - seqState->prevOffset[1] = seqState->prevOffset[0]; - seqState->prevOffset[0] = offset; + if (blockProperties.lastBlock) break; } - seq.offset = offset; - } - - seq.matchLength = ML_base[mlCode] + ((mlCode>31) ? BIT_readBitsFast(&seqState->DStream, mlBits) : 0); /* <= 16 bits */ - if (MEM_32bits() && (mlBits+llBits>24)) BIT_reloadDStream(&seqState->DStream); - - seq.litLength = LL_base[llCode] + ((llCode>15) ? BIT_readBitsFast(&seqState->DStream, llBits) : 0); /* <= 16 bits */ - if (MEM_32bits() || - (totalBits > 64 - 7 - (LLFSELog+MLFSELog+OffFSELog)) ) BIT_reloadDStream(&seqState->DStream); - - { size_t const pos = seqState->pos + seq.litLength; - seq.match = seqState->base + pos - seq.offset; /* single memory segment */ - if (seq.offset > pos) seq.match += seqState->gotoDict; /* separate memory segment */ - seqState->pos = pos + seq.matchLength; - } - /* ANS state update */ - FSE_updateState(&seqState->stateLL, &seqState->DStream); /* <= 9 bits */ - FSE_updateState(&seqState->stateML, &seqState->DStream); /* <= 9 bits */ - if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream); /* <= 18 bits */ - FSE_updateState(&seqState->stateOffb, &seqState->DStream); /* <= 8 bits */ - - return seq; -} - - -HINT_INLINE -size_t ZSTD_execSequenceLong(BYTE* op, - BYTE* const oend, seq_t sequence, - const BYTE** litPtr, const BYTE* const litLimit, - const BYTE* const base, const BYTE* const vBase, const BYTE* const dictEnd) -{ - BYTE* const oLitEnd = op + sequence.litLength; - size_t const sequenceLength = sequence.litLength + sequence.matchLength; - BYTE* const oMatchEnd = op + sequenceLength; /* risk : address space overflow (32-bits) */ - BYTE* const oend_w = oend - WILDCOPY_OVERLENGTH; - const BYTE* const iLitEnd = *litPtr + sequence.litLength; - const BYTE* match = sequence.match; - - /* check */ - if (oMatchEnd>oend) return ERROR(dstSize_tooSmall); /* last match must start at a minimum distance of WILDCOPY_OVERLENGTH from oend */ - if (iLitEnd > litLimit) return ERROR(corruption_detected); /* over-read beyond lit buffer */ - if (oLitEnd>oend_w) return ZSTD_execSequenceLast7(op, oend, sequence, litPtr, litLimit, base, vBase, dictEnd); - - /* copy Literals */ - ZSTD_copy8(op, *litPtr); - if (sequence.litLength > 8) - ZSTD_wildcopy(op+8, (*litPtr)+8, sequence.litLength - 8); /* note : since oLitEnd <= oend-WILDCOPY_OVERLENGTH, no risk of overwrite beyond oend */ - op = oLitEnd; - *litPtr = iLitEnd; /* update for next sequence */ - - /* copy Match */ - if (sequence.offset > (size_t)(oLitEnd - base)) { - /* offset beyond prefix */ - if (sequence.offset > (size_t)(oLitEnd - vBase)) return ERROR(corruption_detected); - if (match + sequence.matchLength <= dictEnd) { - memmove(oLitEnd, match, sequence.matchLength); - return sequenceLength; + /* Final frame content checksum */ + if (zfh.checksumFlag) { + if (remainingSize < 4) + return ZSTD_errorFrameSizeInfo(ERROR(srcSize_wrong)); + ip += 4; } - /* span extDict & currentPrefixSegment */ - { size_t const length1 = dictEnd - match; - memmove(oLitEnd, match, length1); - op = oLitEnd + length1; - sequence.matchLength -= length1; - match = base; - if (op > oend_w || sequence.matchLength < MINMATCH) { - U32 i; - for (i = 0; i < sequence.matchLength; ++i) op[i] = match[i]; - return sequenceLength; - } - } } - assert(op <= oend_w); - assert(sequence.matchLength >= MINMATCH); - - /* match within prefix */ - if (sequence.offset < 8) { - /* close range match, overlap */ - static const U32 dec32table[] = { 0, 1, 2, 1, 4, 4, 4, 4 }; /* added */ - static const int dec64table[] = { 8, 8, 8, 7, 8, 9,10,11 }; /* subtracted */ - int const sub2 = dec64table[sequence.offset]; - op[0] = match[0]; - op[1] = match[1]; - op[2] = match[2]; - op[3] = match[3]; - match += dec32table[sequence.offset]; - ZSTD_copy4(op+4, match); - match -= sub2; - } else { - ZSTD_copy8(op, match); - } - op += 8; match += 8; - if (oMatchEnd > oend-(16-MINMATCH)) { - if (op < oend_w) { - ZSTD_wildcopy(op, match, oend_w - op); - match += oend_w - op; - op = oend_w; - } - while (op < oMatchEnd) *op++ = *match++; - } else { - ZSTD_wildcopy(op, match, (ptrdiff_t)sequence.matchLength-8); /* works even if matchLength < 8 */ + frameSizeInfo.compressedSize = ip - ipstart; + frameSizeInfo.decompressedBound = (zfh.frameContentSize != ZSTD_CONTENTSIZE_UNKNOWN) + ? zfh.frameContentSize + : nbBlocks * zfh.blockSizeMax; + return frameSizeInfo; } - return sequenceLength; } -static size_t ZSTD_decompressSequencesLong( - ZSTD_DCtx* dctx, - void* dst, size_t maxDstSize, - const void* seqStart, size_t seqSize, - const ZSTD_longOffset_e isLongOffset) +/** ZSTD_findFrameCompressedSize() : + * compatible with legacy mode + * `src` must point to the start of a ZSTD frame, ZSTD legacy frame, or skippable frame + * `srcSize` must be at least as large as the frame contained + * @return : the compressed size of the frame starting at `src` */ +size_t ZSTD_findFrameCompressedSize(const void *src, size_t srcSize) { - const BYTE* ip = (const BYTE*)seqStart; - const BYTE* const iend = ip + seqSize; - BYTE* const ostart = (BYTE* const)dst; - BYTE* const oend = ostart + maxDstSize; - BYTE* op = ostart; - const BYTE* litPtr = dctx->litPtr; - const BYTE* const litEnd = litPtr + dctx->litSize; - const BYTE* const base = (const BYTE*) (dctx->base); - const BYTE* const vBase = (const BYTE*) (dctx->vBase); - const BYTE* const dictEnd = (const BYTE*) (dctx->dictEnd); - int nbSeq; - - /* Build Decoding Tables */ - { size_t const seqHSize = ZSTD_decodeSeqHeaders(dctx, &nbSeq, ip, seqSize); - if (ZSTD_isError(seqHSize)) return seqHSize; - ip += seqHSize; - } - - /* Regen sequences */ - if (nbSeq) { -#define STORED_SEQS 4 -#define STOSEQ_MASK (STORED_SEQS-1) -#define ADVANCED_SEQS 4 - seq_t sequences[STORED_SEQS]; - int const seqAdvance = MIN(nbSeq, ADVANCED_SEQS); - seqState_t seqState; - int seqNb; - dctx->fseEntropy = 1; - { U32 i; for (i=0; i<ZSTD_REP_NUM; i++) seqState.prevOffset[i] = dctx->entropy.rep[i]; } - seqState.base = base; - seqState.pos = (size_t)(op-base); - seqState.gotoDict = (uPtrDiff)dictEnd - (uPtrDiff)base; /* cast to avoid undefined behaviour */ - CHECK_E(BIT_initDStream(&seqState.DStream, ip, iend-ip), corruption_detected); - FSE_initDState(&seqState.stateLL, &seqState.DStream, dctx->LLTptr); - FSE_initDState(&seqState.stateOffb, &seqState.DStream, dctx->OFTptr); - FSE_initDState(&seqState.stateML, &seqState.DStream, dctx->MLTptr); - - /* prepare in advance */ - for (seqNb=0; (BIT_reloadDStream(&seqState.DStream) <= BIT_DStream_completed) && seqNb<seqAdvance; seqNb++) { - sequences[seqNb] = ZSTD_decodeSequenceLong(&seqState, isLongOffset); - } - if (seqNb<seqAdvance) return ERROR(corruption_detected); - - /* decode and decompress */ - for ( ; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && seqNb<nbSeq ; seqNb++) { - seq_t const sequence = ZSTD_decodeSequenceLong(&seqState, isLongOffset); - size_t const oneSeqSize = ZSTD_execSequenceLong(op, oend, sequences[(seqNb-ADVANCED_SEQS) & STOSEQ_MASK], &litPtr, litEnd, base, vBase, dictEnd); - if (ZSTD_isError(oneSeqSize)) return oneSeqSize; - PREFETCH(sequence.match); - sequences[seqNb&STOSEQ_MASK] = sequence; - op += oneSeqSize; - } - if (seqNb<nbSeq) return ERROR(corruption_detected); - - /* finish queue */ - seqNb -= seqAdvance; - for ( ; seqNb<nbSeq ; seqNb++) { - size_t const oneSeqSize = ZSTD_execSequenceLong(op, oend, sequences[seqNb&STOSEQ_MASK], &litPtr, litEnd, base, vBase, dictEnd); - if (ZSTD_isError(oneSeqSize)) return oneSeqSize; - op += oneSeqSize; - } - - /* save reps for next block */ - { U32 i; for (i=0; i<ZSTD_REP_NUM; i++) dctx->entropy.rep[i] = (U32)(seqState.prevOffset[i]); } - } - - /* last literal segment */ - { size_t const lastLLSize = litEnd - litPtr; - if (lastLLSize > (size_t)(oend-op)) return ERROR(dstSize_tooSmall); - memcpy(op, litPtr, lastLLSize); - op += lastLLSize; - } - - return op-ostart; -} - - -static size_t ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx, - void* dst, size_t dstCapacity, - const void* src, size_t srcSize, const int frame) -{ /* blockType == blockCompressed */ - const BYTE* ip = (const BYTE*)src; - /* isLongOffset must be true if there are long offsets. - * Offsets are long if they are larger than 2^STREAM_ACCUMULATOR_MIN. - * We don't expect that to be the case in 64-bit mode. - * If we are in block mode we don't know the window size, so we have to be - * conservative. - */ - ZSTD_longOffset_e const isLongOffset = (ZSTD_longOffset_e)(MEM_32bits() && (!frame || dctx->fParams.windowSize > (1ULL << STREAM_ACCUMULATOR_MIN))); - /* windowSize could be any value at this point, since it is only validated - * in the streaming API. - */ - DEBUGLOG(5, "ZSTD_decompressBlock_internal"); - - if (srcSize >= ZSTD_BLOCKSIZE_MAX) return ERROR(srcSize_wrong); - - /* Decode literals section */ - { size_t const litCSize = ZSTD_decodeLiteralsBlock(dctx, src, srcSize); - DEBUGLOG(5, "ZSTD_decodeLiteralsBlock : %u", (U32)litCSize); - if (ZSTD_isError(litCSize)) return litCSize; - ip += litCSize; - srcSize -= litCSize; - } - if (frame && dctx->fParams.windowSize > (1<<23)) - return ZSTD_decompressSequencesLong(dctx, dst, dstCapacity, ip, srcSize, isLongOffset); - return ZSTD_decompressSequences(dctx, dst, dstCapacity, ip, srcSize, isLongOffset); + ZSTD_frameSizeInfo const frameSizeInfo = ZSTD_findFrameSizeInfo(src, srcSize); + return frameSizeInfo.compressedSize; } - -static void ZSTD_checkContinuity(ZSTD_DCtx* dctx, const void* dst) -{ - if (dst != dctx->previousDstEnd) { /* not contiguous */ - dctx->dictEnd = dctx->previousDstEnd; - dctx->vBase = (const char*)dst - ((const char*)(dctx->previousDstEnd) - (const char*)(dctx->base)); - dctx->base = dst; - dctx->previousDstEnd = dst; +/** ZSTD_decompressBound() : + * compatible with legacy mode + * `src` must point to the start of a ZSTD frame or a skippeable frame + * `srcSize` must be at least as large as the frame contained + * @return : the maximum decompressed size of the compressed source + */ +unsigned long long ZSTD_decompressBound(const void* src, size_t srcSize) +{ + unsigned long long bound = 0; + /* Iterate over each frame */ + while (srcSize > 0) { + ZSTD_frameSizeInfo const frameSizeInfo = ZSTD_findFrameSizeInfo(src, srcSize); + size_t const compressedSize = frameSizeInfo.compressedSize; + unsigned long long const decompressedBound = frameSizeInfo.decompressedBound; + if (ZSTD_isError(compressedSize) || decompressedBound == ZSTD_CONTENTSIZE_ERROR) + return ZSTD_CONTENTSIZE_ERROR; + assert(srcSize >= compressedSize); + src = (const BYTE*)src + compressedSize; + srcSize -= compressedSize; + bound += decompressedBound; } + return bound; } -size_t ZSTD_decompressBlock(ZSTD_DCtx* dctx, - void* dst, size_t dstCapacity, - const void* src, size_t srcSize) -{ - size_t dSize; - ZSTD_checkContinuity(dctx, dst); - dSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize, /* frame */ 0); - dctx->previousDstEnd = (char*)dst + dSize; - return dSize; -} +/*-************************************************************* + * Frame decoding + ***************************************************************/ /** ZSTD_insertBlock() : - insert `src` block into `dctx` history. Useful to track uncompressed blocks. */ -ZSTDLIB_API size_t ZSTD_insertBlock(ZSTD_DCtx* dctx, const void* blockStart, size_t blockSize) + * insert `src` block into `dctx` history. Useful to track uncompressed blocks. */ +size_t ZSTD_insertBlock(ZSTD_DCtx* dctx, const void* blockStart, size_t blockSize) { + DEBUGLOG(5, "ZSTD_insertBlock: %u bytes", (unsigned)blockSize); ZSTD_checkContinuity(dctx, blockStart); dctx->previousDstEnd = (const char*)blockStart + blockSize; return blockSize; } -size_t ZSTD_generateNxBytes(void* dst, size_t dstCapacity, BYTE byte, size_t length) +static size_t ZSTD_copyRawBlock(void* dst, size_t dstCapacity, + const void* src, size_t srcSize) { - if (length > dstCapacity) return ERROR(dstSize_tooSmall); - memset(dst, byte, length); - return length; + DEBUGLOG(5, "ZSTD_copyRawBlock"); + if (dst == NULL) { + if (srcSize == 0) return 0; + RETURN_ERROR(dstBuffer_null, ""); + } + RETURN_ERROR_IF(srcSize > dstCapacity, dstSize_tooSmall, ""); + memcpy(dst, src, srcSize); + return srcSize; } -/** ZSTD_findFrameCompressedSize() : - * compatible with legacy mode - * `src` must point to the start of a ZSTD frame, ZSTD legacy frame, or skippable frame - * `srcSize` must be at least as large as the frame contained - * @return : the compressed size of the frame starting at `src` */ -size_t ZSTD_findFrameCompressedSize(const void *src, size_t srcSize) +static size_t ZSTD_setRleBlock(void* dst, size_t dstCapacity, + BYTE b, + size_t regenSize) { -#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT >= 1) - if (ZSTD_isLegacy(src, srcSize)) - return ZSTD_findFrameCompressedSizeLegacy(src, srcSize); -#endif - if ( (srcSize >= ZSTD_skippableHeaderSize) - && (MEM_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START ) { - return ZSTD_skippableHeaderSize + MEM_readLE32((const BYTE*)src + 4); - } else { - const BYTE* ip = (const BYTE*)src; - const BYTE* const ipstart = ip; - size_t remainingSize = srcSize; - ZSTD_frameHeader zfh; - - /* Extract Frame Header */ - { size_t const ret = ZSTD_getFrameHeader(&zfh, src, srcSize); - if (ZSTD_isError(ret)) return ret; - if (ret > 0) return ERROR(srcSize_wrong); - } - - ip += zfh.headerSize; - remainingSize -= zfh.headerSize; - - /* Loop on each block */ - while (1) { - blockProperties_t blockProperties; - size_t const cBlockSize = ZSTD_getcBlockSize(ip, remainingSize, &blockProperties); - if (ZSTD_isError(cBlockSize)) return cBlockSize; - - if (ZSTD_blockHeaderSize + cBlockSize > remainingSize) - return ERROR(srcSize_wrong); - - ip += ZSTD_blockHeaderSize + cBlockSize; - remainingSize -= ZSTD_blockHeaderSize + cBlockSize; - - if (blockProperties.lastBlock) break; - } - - if (zfh.checksumFlag) { /* Final frame content checksum */ - if (remainingSize < 4) return ERROR(srcSize_wrong); - ip += 4; - remainingSize -= 4; - } - - return ip - ipstart; + if (dst == NULL) { + if (regenSize == 0) return 0; + RETURN_ERROR(dstBuffer_null, ""); } + RETURN_ERROR_IF(regenSize > dstCapacity, dstSize_tooSmall, ""); + memset(dst, b, regenSize); + return regenSize; } + /*! ZSTD_decompressFrame() : -* @dctx must be properly initialized */ + * @dctx must be properly initialized + * will update *srcPtr and *srcSizePtr, + * to make *srcPtr progress by one frame. */ static size_t ZSTD_decompressFrame(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void** srcPtr, size_t *srcSizePtr) { const BYTE* ip = (const BYTE*)(*srcPtr); BYTE* const ostart = (BYTE* const)dst; - BYTE* const oend = ostart + dstCapacity; + BYTE* const oend = dstCapacity != 0 ? ostart + dstCapacity : ostart; BYTE* op = ostart; - size_t remainingSize = *srcSizePtr; + size_t remainingSrcSize = *srcSizePtr; + + DEBUGLOG(4, "ZSTD_decompressFrame (srcSize:%i)", (int)*srcSizePtr); /* check */ - if (remainingSize < ZSTD_frameHeaderSize_min+ZSTD_blockHeaderSize) - return ERROR(srcSize_wrong); + RETURN_ERROR_IF( + remainingSrcSize < ZSTD_FRAMEHEADERSIZE_MIN(dctx->format)+ZSTD_blockHeaderSize, + srcSize_wrong, ""); /* Frame Header */ - { size_t const frameHeaderSize = ZSTD_frameHeaderSize(ip, ZSTD_frameHeaderSize_prefix); + { size_t const frameHeaderSize = ZSTD_frameHeaderSize_internal( + ip, ZSTD_FRAMEHEADERSIZE_PREFIX(dctx->format), dctx->format); if (ZSTD_isError(frameHeaderSize)) return frameHeaderSize; - if (remainingSize < frameHeaderSize+ZSTD_blockHeaderSize) - return ERROR(srcSize_wrong); - CHECK_F( ZSTD_decodeFrameHeader(dctx, ip, frameHeaderSize) ); - ip += frameHeaderSize; remainingSize -= frameHeaderSize; + RETURN_ERROR_IF(remainingSrcSize < frameHeaderSize+ZSTD_blockHeaderSize, + srcSize_wrong, ""); + FORWARD_IF_ERROR( ZSTD_decodeFrameHeader(dctx, ip, frameHeaderSize) , ""); + ip += frameHeaderSize; remainingSrcSize -= frameHeaderSize; } /* Loop on each block */ while (1) { size_t decodedSize; blockProperties_t blockProperties; - size_t const cBlockSize = ZSTD_getcBlockSize(ip, remainingSize, &blockProperties); + size_t const cBlockSize = ZSTD_getcBlockSize(ip, remainingSrcSize, &blockProperties); if (ZSTD_isError(cBlockSize)) return cBlockSize; ip += ZSTD_blockHeaderSize; - remainingSize -= ZSTD_blockHeaderSize; - if (cBlockSize > remainingSize) return ERROR(srcSize_wrong); + remainingSrcSize -= ZSTD_blockHeaderSize; + RETURN_ERROR_IF(cBlockSize > remainingSrcSize, srcSize_wrong, ""); switch(blockProperties.blockType) { @@ -1530,41 +653,44 @@ static size_t ZSTD_decompressFrame(ZSTD_DCtx* dctx, decodedSize = ZSTD_copyRawBlock(op, oend-op, ip, cBlockSize); break; case bt_rle : - decodedSize = ZSTD_generateNxBytes(op, oend-op, *ip, blockProperties.origSize); + decodedSize = ZSTD_setRleBlock(op, oend-op, *ip, blockProperties.origSize); break; case bt_reserved : default: - return ERROR(corruption_detected); + RETURN_ERROR(corruption_detected, "invalid block type"); } if (ZSTD_isError(decodedSize)) return decodedSize; if (dctx->fParams.checksumFlag) XXH64_update(&dctx->xxhState, op, decodedSize); - op += decodedSize; + if (decodedSize != 0) + op += decodedSize; + assert(ip != NULL); ip += cBlockSize; - remainingSize -= cBlockSize; + remainingSrcSize -= cBlockSize; if (blockProperties.lastBlock) break; } + if (dctx->fParams.frameContentSize != ZSTD_CONTENTSIZE_UNKNOWN) { + RETURN_ERROR_IF((U64)(op-ostart) != dctx->fParams.frameContentSize, + corruption_detected, ""); + } if (dctx->fParams.checksumFlag) { /* Frame content checksum verification */ U32 const checkCalc = (U32)XXH64_digest(&dctx->xxhState); U32 checkRead; - if (remainingSize<4) return ERROR(checksum_wrong); + RETURN_ERROR_IF(remainingSrcSize<4, checksum_wrong, ""); checkRead = MEM_readLE32(ip); - if (checkRead != checkCalc) return ERROR(checksum_wrong); + RETURN_ERROR_IF(checkRead != checkCalc, checksum_wrong, ""); ip += 4; - remainingSize -= 4; + remainingSrcSize -= 4; } /* Allow caller to get size read */ *srcPtr = ip; - *srcSizePtr = remainingSize; + *srcSizePtr = remainingSrcSize; return op-ostart; } -static const void* ZSTD_DDictDictContent(const ZSTD_DDict* ddict); -static size_t ZSTD_DDictDictSize(const ZSTD_DDict* ddict); - static size_t ZSTD_decompressMultiFrame(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize, @@ -1572,26 +698,30 @@ static size_t ZSTD_decompressMultiFrame(ZSTD_DCtx* dctx, const ZSTD_DDict* ddict) { void* const dststart = dst; + int moreThan1Frame = 0; + + DEBUGLOG(5, "ZSTD_decompressMultiFrame"); assert(dict==NULL || ddict==NULL); /* either dict or ddict set, not both */ if (ddict) { - dict = ZSTD_DDictDictContent(ddict); - dictSize = ZSTD_DDictDictSize(ddict); + dict = ZSTD_DDict_dictContent(ddict); + dictSize = ZSTD_DDict_dictSize(ddict); } - while (srcSize >= ZSTD_frameHeaderSize_prefix) { - U32 magicNumber; + while (srcSize >= ZSTD_startingInputLength(dctx->format)) { #if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT >= 1) if (ZSTD_isLegacy(src, srcSize)) { size_t decodedSize; size_t const frameSize = ZSTD_findFrameCompressedSizeLegacy(src, srcSize); if (ZSTD_isError(frameSize)) return frameSize; - /* legacy support is not compatible with static dctx */ - if (dctx->staticSize) return ERROR(memory_allocation); + RETURN_ERROR_IF(dctx->staticSize, memory_allocation, + "legacy support is not compatible with static dctx"); decodedSize = ZSTD_decompressLegacy(dst, dstCapacity, src, frameSize, dict, dictSize); + if (ZSTD_isError(decodedSize)) return decodedSize; + assert(decodedSize <=- dstCapacity); dst = (BYTE*)dst + decodedSize; dstCapacity -= decodedSize; @@ -1602,43 +732,54 @@ static size_t ZSTD_decompressMultiFrame(ZSTD_DCtx* dctx, } #endif - magicNumber = MEM_readLE32(src); - if (magicNumber != ZSTD_MAGICNUMBER) { - if ((magicNumber & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { - size_t skippableSize; - if (srcSize < ZSTD_skippableHeaderSize) - return ERROR(srcSize_wrong); - skippableSize = MEM_readLE32((const BYTE *)src + 4) + - ZSTD_skippableHeaderSize; - if (srcSize < skippableSize) return ERROR(srcSize_wrong); + { U32 const magicNumber = MEM_readLE32(src); + DEBUGLOG(4, "reading magic number %08X (expecting %08X)", + (unsigned)magicNumber, ZSTD_MAGICNUMBER); + if ((magicNumber & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) { + size_t const skippableSize = readSkippableFrameSize(src, srcSize); + FORWARD_IF_ERROR(skippableSize, "readSkippableFrameSize failed"); + assert(skippableSize <= srcSize); src = (const BYTE *)src + skippableSize; srcSize -= skippableSize; continue; - } - return ERROR(prefix_unknown); - } + } } if (ddict) { /* we were called from ZSTD_decompress_usingDDict */ - CHECK_F(ZSTD_decompressBegin_usingDDict(dctx, ddict)); + FORWARD_IF_ERROR(ZSTD_decompressBegin_usingDDict(dctx, ddict), ""); } else { /* this will initialize correctly with no dict if dict == NULL, so * use this in all cases but ddict */ - CHECK_F(ZSTD_decompressBegin_usingDict(dctx, dict, dictSize)); + FORWARD_IF_ERROR(ZSTD_decompressBegin_usingDict(dctx, dict, dictSize), ""); } ZSTD_checkContinuity(dctx, dst); { const size_t res = ZSTD_decompressFrame(dctx, dst, dstCapacity, &src, &srcSize); + RETURN_ERROR_IF( + (ZSTD_getErrorCode(res) == ZSTD_error_prefix_unknown) + && (moreThan1Frame==1), + srcSize_wrong, + "at least one frame successfully completed, but following " + "bytes are garbage: it's more likely to be a srcSize error, " + "specifying more bytes than compressed size of frame(s). This " + "error message replaces ERROR(prefix_unknown), which would be " + "confusing, as the first header is actually correct. Note that " + "one could be unlucky, it might be a corruption error instead, " + "happening right at the place where we expect zstd magic " + "bytes. But this is _much_ less likely than a srcSize field " + "error."); if (ZSTD_isError(res)) return res; - /* no need to bound check, ZSTD_decompressFrame already has */ - dst = (BYTE*)dst + res; + assert(res <= dstCapacity); + if (res != 0) + dst = (BYTE*)dst + res; dstCapacity -= res; } + moreThan1Frame = 1; } /* while (srcSize >= ZSTD_frameHeaderSize_prefix) */ - if (srcSize) return ERROR(srcSize_wrong); /* input not entirely consumed */ + RETURN_ERROR_IF(srcSize, srcSize_wrong, "input not entirely consumed"); return (BYTE*)dst - (BYTE*)dststart; } @@ -1652,9 +793,26 @@ size_t ZSTD_decompress_usingDict(ZSTD_DCtx* dctx, } +static ZSTD_DDict const* ZSTD_getDDict(ZSTD_DCtx* dctx) +{ + switch (dctx->dictUses) { + default: + assert(0 /* Impossible */); + /* fall-through */ + case ZSTD_dont_use: + ZSTD_clearDict(dctx); + return NULL; + case ZSTD_use_indefinitely: + return dctx->ddict; + case ZSTD_use_once: + dctx->dictUses = ZSTD_dont_use; + return dctx->ddict; + } +} + size_t ZSTD_decompressDCtx(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize) { - return ZSTD_decompress_usingDict(dctx, dst, dstCapacity, src, srcSize, NULL, 0); + return ZSTD_decompress_usingDDict(dctx, dst, dstCapacity, src, srcSize, ZSTD_getDDict(dctx)); } @@ -1663,12 +821,13 @@ size_t ZSTD_decompress(void* dst, size_t dstCapacity, const void* src, size_t sr #if defined(ZSTD_HEAPMODE) && (ZSTD_HEAPMODE>=1) size_t regenSize; ZSTD_DCtx* const dctx = ZSTD_createDCtx(); - if (dctx==NULL) return ERROR(memory_allocation); + RETURN_ERROR_IF(dctx==NULL, memory_allocation, "NULL pointer!"); regenSize = ZSTD_decompressDCtx(dctx, dst, dstCapacity, src, srcSize); ZSTD_freeDCtx(dctx); return regenSize; #else /* stack mode */ ZSTD_DCtx dctx; + ZSTD_initDCtx_internal(&dctx); return ZSTD_decompressDCtx(&dctx, dst, dstCapacity, src, srcSize); #endif } @@ -1680,6 +839,24 @@ size_t ZSTD_decompress(void* dst, size_t dstCapacity, const void* src, size_t sr ****************************************/ size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx* dctx) { return dctx->expected; } +/** + * Similar to ZSTD_nextSrcSizeToDecompress(), but when when a block input can be streamed, + * we allow taking a partial block as the input. Currently only raw uncompressed blocks can + * be streamed. + * + * For blocks that can be streamed, this allows us to reduce the latency until we produce + * output, and avoid copying the input. + * + * @param inputSize - The total amount of input that the caller currently has. + */ +static size_t ZSTD_nextSrcSizeToDecompressWithInputSize(ZSTD_DCtx* dctx, size_t inputSize) { + if (!(dctx->stage == ZSTDds_decompressBlock || dctx->stage == ZSTDds_decompressLastBlock)) + return dctx->expected; + if (dctx->bType != bt_raw) + return dctx->expected; + return MIN(MAX(inputSize, 1), dctx->expected); +} + ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx) { switch(dctx->stage) { @@ -1710,36 +887,34 @@ static int ZSTD_isSkipFrame(ZSTD_DCtx* dctx) { return dctx->stage == ZSTDds_skip * or an error code, which can be tested using ZSTD_isError() */ size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize) { - DEBUGLOG(5, "ZSTD_decompressContinue"); + DEBUGLOG(5, "ZSTD_decompressContinue (srcSize:%u)", (unsigned)srcSize); /* Sanity check */ - if (srcSize != dctx->expected) return ERROR(srcSize_wrong); /* unauthorized */ + RETURN_ERROR_IF(srcSize != ZSTD_nextSrcSizeToDecompressWithInputSize(dctx, srcSize), srcSize_wrong, "not allowed"); if (dstCapacity) ZSTD_checkContinuity(dctx, dst); switch (dctx->stage) { case ZSTDds_getFrameHeaderSize : - if (srcSize != ZSTD_frameHeaderSize_prefix) return ERROR(srcSize_wrong); /* unauthorized */ assert(src != NULL); - if ((MEM_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { /* skippable frame */ - memcpy(dctx->headerBuffer, src, ZSTD_frameHeaderSize_prefix); - dctx->expected = ZSTD_skippableHeaderSize - ZSTD_frameHeaderSize_prefix; /* magic number + skippable frame length */ - dctx->stage = ZSTDds_decodeSkippableHeader; - return 0; - } - dctx->headerSize = ZSTD_frameHeaderSize(src, ZSTD_frameHeaderSize_prefix); + if (dctx->format == ZSTD_f_zstd1) { /* allows header */ + assert(srcSize >= ZSTD_FRAMEIDSIZE); /* to read skippable magic number */ + if ((MEM_readLE32(src) & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) { /* skippable frame */ + memcpy(dctx->headerBuffer, src, srcSize); + dctx->expected = ZSTD_SKIPPABLEHEADERSIZE - srcSize; /* remaining to load to get full skippable frame header */ + dctx->stage = ZSTDds_decodeSkippableHeader; + return 0; + } } + dctx->headerSize = ZSTD_frameHeaderSize_internal(src, srcSize, dctx->format); if (ZSTD_isError(dctx->headerSize)) return dctx->headerSize; - memcpy(dctx->headerBuffer, src, ZSTD_frameHeaderSize_prefix); - if (dctx->headerSize > ZSTD_frameHeaderSize_prefix) { - dctx->expected = dctx->headerSize - ZSTD_frameHeaderSize_prefix; - dctx->stage = ZSTDds_decodeFrameHeader; - return 0; - } - dctx->expected = 0; /* not necessary to copy more */ - /* fall-through */ + memcpy(dctx->headerBuffer, src, srcSize); + dctx->expected = dctx->headerSize - srcSize; + dctx->stage = ZSTDds_decodeFrameHeader; + return 0; + case ZSTDds_decodeFrameHeader: assert(src != NULL); - memcpy(dctx->headerBuffer + ZSTD_frameHeaderSize_prefix, src, dctx->expected); - CHECK_F(ZSTD_decodeFrameHeader(dctx, dctx->headerBuffer, dctx->headerSize)); + memcpy(dctx->headerBuffer + (dctx->headerSize - srcSize), src, srcSize); + FORWARD_IF_ERROR(ZSTD_decodeFrameHeader(dctx, dctx->headerBuffer, dctx->headerSize), ""); dctx->expected = ZSTD_blockHeaderSize; dctx->stage = ZSTDds_decodeBlockHeader; return 0; @@ -1748,6 +923,7 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, c { blockProperties_t bp; size_t const cBlockSize = ZSTD_getcBlockSize(src, ZSTD_blockHeaderSize, &bp); if (ZSTD_isError(cBlockSize)) return cBlockSize; + RETURN_ERROR_IF(cBlockSize > dctx->fParams.blockSizeMax, corruption_detected, "Block Size Exceeds Maximum"); dctx->expected = cBlockSize; dctx->bType = bp.blockType; dctx->rleSize = bp.origSize; @@ -1770,37 +946,51 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, c } return 0; } + case ZSTDds_decompressLastBlock: case ZSTDds_decompressBlock: - DEBUGLOG(5, "case ZSTDds_decompressBlock"); + DEBUGLOG(5, "ZSTD_decompressContinue: case ZSTDds_decompressBlock"); { size_t rSize; switch(dctx->bType) { case bt_compressed: - DEBUGLOG(5, "case bt_compressed"); + DEBUGLOG(5, "ZSTD_decompressContinue: case bt_compressed"); rSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize, /* frame */ 1); + dctx->expected = 0; /* Streaming not supported */ break; case bt_raw : + assert(srcSize <= dctx->expected); rSize = ZSTD_copyRawBlock(dst, dstCapacity, src, srcSize); + FORWARD_IF_ERROR(rSize, "ZSTD_copyRawBlock failed"); + assert(rSize == srcSize); + dctx->expected -= rSize; break; case bt_rle : - rSize = ZSTD_setRleBlock(dst, dstCapacity, src, srcSize, dctx->rleSize); + rSize = ZSTD_setRleBlock(dst, dstCapacity, *(const BYTE*)src, dctx->rleSize); + dctx->expected = 0; /* Streaming not supported */ break; case bt_reserved : /* should never happen */ default: - return ERROR(corruption_detected); + RETURN_ERROR(corruption_detected, "invalid block type"); } - if (ZSTD_isError(rSize)) return rSize; - DEBUGLOG(5, "decoded size from block : %u", (U32)rSize); + FORWARD_IF_ERROR(rSize, ""); + RETURN_ERROR_IF(rSize > dctx->fParams.blockSizeMax, corruption_detected, "Decompressed Block Size Exceeds Maximum"); + DEBUGLOG(5, "ZSTD_decompressContinue: decoded size from block : %u", (unsigned)rSize); dctx->decodedSize += rSize; if (dctx->fParams.checksumFlag) XXH64_update(&dctx->xxhState, dst, rSize); + dctx->previousDstEnd = (char*)dst + rSize; + + /* Stay on the same stage until we are finished streaming the block. */ + if (dctx->expected > 0) { + return rSize; + } if (dctx->stage == ZSTDds_decompressLastBlock) { /* end of frame */ - DEBUGLOG(4, "decoded size from frame : %u", (U32)dctx->decodedSize); - if (dctx->fParams.frameContentSize != ZSTD_CONTENTSIZE_UNKNOWN) { - if (dctx->decodedSize != dctx->fParams.frameContentSize) { - return ERROR(corruption_detected); - } } + DEBUGLOG(4, "ZSTD_decompressContinue: decoded size from frame : %u", (unsigned)dctx->decodedSize); + RETURN_ERROR_IF( + dctx->fParams.frameContentSize != ZSTD_CONTENTSIZE_UNKNOWN + && dctx->decodedSize != dctx->fParams.frameContentSize, + corruption_detected, ""); if (dctx->fParams.checksumFlag) { /* another round for frame checksum */ dctx->expected = 4; dctx->stage = ZSTDds_checkChecksum; @@ -1811,35 +1001,37 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, c } else { dctx->stage = ZSTDds_decodeBlockHeader; dctx->expected = ZSTD_blockHeaderSize; - dctx->previousDstEnd = (char*)dst + rSize; } return rSize; } + case ZSTDds_checkChecksum: - DEBUGLOG(4, "case ZSTDds_checkChecksum"); assert(srcSize == 4); /* guaranteed by dctx->expected */ { U32 const h32 = (U32)XXH64_digest(&dctx->xxhState); U32 const check32 = MEM_readLE32(src); - DEBUGLOG(4, "calculated %08X :: %08X read", h32, check32); - if (check32 != h32) return ERROR(checksum_wrong); + DEBUGLOG(4, "ZSTD_decompressContinue: checksum : calculated %08X :: %08X read", (unsigned)h32, (unsigned)check32); + RETURN_ERROR_IF(check32 != h32, checksum_wrong, ""); dctx->expected = 0; dctx->stage = ZSTDds_getFrameHeaderSize; return 0; } + case ZSTDds_decodeSkippableHeader: - { assert(src != NULL); - memcpy(dctx->headerBuffer + ZSTD_frameHeaderSize_prefix, src, dctx->expected); - dctx->expected = MEM_readLE32(dctx->headerBuffer + 4); - dctx->stage = ZSTDds_skipFrame; - return 0; - } + assert(src != NULL); + assert(srcSize <= ZSTD_SKIPPABLEHEADERSIZE); + memcpy(dctx->headerBuffer + (ZSTD_SKIPPABLEHEADERSIZE - srcSize), src, srcSize); /* complete skippable header */ + dctx->expected = MEM_readLE32(dctx->headerBuffer + ZSTD_FRAMEIDSIZE); /* note : dctx->expected can grow seriously large, beyond local buffer size */ + dctx->stage = ZSTDds_skipFrame; + return 0; + case ZSTDds_skipFrame: - { dctx->expected = 0; - dctx->stage = ZSTDds_getFrameHeaderSize; - return 0; - } + dctx->expected = 0; + dctx->stage = ZSTDds_getFrameHeaderSize; + return 0; + default: - return ERROR(GENERIC); /* impossible */ + assert(0); /* impossible */ + RETURN_ERROR(GENERIC, "impossible to reach"); /* some compiler require default to do something */ } } @@ -1847,64 +1039,95 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, c static size_t ZSTD_refDictContent(ZSTD_DCtx* dctx, const void* dict, size_t dictSize) { dctx->dictEnd = dctx->previousDstEnd; - dctx->vBase = (const char*)dict - ((const char*)(dctx->previousDstEnd) - (const char*)(dctx->base)); - dctx->base = dict; + dctx->virtualStart = (const char*)dict - ((const char*)(dctx->previousDstEnd) - (const char*)(dctx->prefixStart)); + dctx->prefixStart = dict; dctx->previousDstEnd = (const char*)dict + dictSize; +#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION + dctx->dictContentBeginForFuzzing = dctx->prefixStart; + dctx->dictContentEndForFuzzing = dctx->previousDstEnd; +#endif return 0; } -/* ZSTD_loadEntropy() : - * dict : must point at beginning of a valid zstd dictionary +/*! ZSTD_loadDEntropy() : + * dict : must point at beginning of a valid zstd dictionary. * @return : size of entropy tables read */ -static size_t ZSTD_loadEntropy(ZSTD_entropyDTables_t* entropy, const void* const dict, size_t const dictSize) +size_t +ZSTD_loadDEntropy(ZSTD_entropyDTables_t* entropy, + const void* const dict, size_t const dictSize) { const BYTE* dictPtr = (const BYTE*)dict; const BYTE* const dictEnd = dictPtr + dictSize; - if (dictSize <= 8) return ERROR(dictionary_corrupted); + RETURN_ERROR_IF(dictSize <= 8, dictionary_corrupted, "dict is too small"); + assert(MEM_readLE32(dict) == ZSTD_MAGIC_DICTIONARY); /* dict must be valid */ dictPtr += 8; /* skip header = magic + dictID */ - - { size_t const hSize = HUF_readDTableX4_wksp( - entropy->hufTable, dictPtr, dictEnd - dictPtr, - entropy->workspace, sizeof(entropy->workspace)); - if (HUF_isError(hSize)) return ERROR(dictionary_corrupted); + ZSTD_STATIC_ASSERT(offsetof(ZSTD_entropyDTables_t, OFTable) == offsetof(ZSTD_entropyDTables_t, LLTable) + sizeof(entropy->LLTable)); + ZSTD_STATIC_ASSERT(offsetof(ZSTD_entropyDTables_t, MLTable) == offsetof(ZSTD_entropyDTables_t, OFTable) + sizeof(entropy->OFTable)); + ZSTD_STATIC_ASSERT(sizeof(entropy->LLTable) + sizeof(entropy->OFTable) + sizeof(entropy->MLTable) >= HUF_DECOMPRESS_WORKSPACE_SIZE); + { void* const workspace = &entropy->LLTable; /* use fse tables as temporary workspace; implies fse tables are grouped together */ + size_t const workspaceSize = sizeof(entropy->LLTable) + sizeof(entropy->OFTable) + sizeof(entropy->MLTable); +#ifdef HUF_FORCE_DECOMPRESS_X1 + /* in minimal huffman, we always use X1 variants */ + size_t const hSize = HUF_readDTableX1_wksp(entropy->hufTable, + dictPtr, dictEnd - dictPtr, + workspace, workspaceSize); +#else + size_t const hSize = HUF_readDTableX2_wksp(entropy->hufTable, + dictPtr, dictEnd - dictPtr, + workspace, workspaceSize); +#endif + RETURN_ERROR_IF(HUF_isError(hSize), dictionary_corrupted, ""); dictPtr += hSize; } { short offcodeNCount[MaxOff+1]; - U32 offcodeMaxValue = MaxOff, offcodeLog; + unsigned offcodeMaxValue = MaxOff, offcodeLog; size_t const offcodeHeaderSize = FSE_readNCount(offcodeNCount, &offcodeMaxValue, &offcodeLog, dictPtr, dictEnd-dictPtr); - if (FSE_isError(offcodeHeaderSize)) return ERROR(dictionary_corrupted); - if (offcodeLog > OffFSELog) return ERROR(dictionary_corrupted); - CHECK_E(FSE_buildDTable(entropy->OFTable, offcodeNCount, offcodeMaxValue, offcodeLog), dictionary_corrupted); + RETURN_ERROR_IF(FSE_isError(offcodeHeaderSize), dictionary_corrupted, ""); + RETURN_ERROR_IF(offcodeMaxValue > MaxOff, dictionary_corrupted, ""); + RETURN_ERROR_IF(offcodeLog > OffFSELog, dictionary_corrupted, ""); + ZSTD_buildFSETable( entropy->OFTable, + offcodeNCount, offcodeMaxValue, + OF_base, OF_bits, + offcodeLog); dictPtr += offcodeHeaderSize; } { short matchlengthNCount[MaxML+1]; unsigned matchlengthMaxValue = MaxML, matchlengthLog; size_t const matchlengthHeaderSize = FSE_readNCount(matchlengthNCount, &matchlengthMaxValue, &matchlengthLog, dictPtr, dictEnd-dictPtr); - if (FSE_isError(matchlengthHeaderSize)) return ERROR(dictionary_corrupted); - if (matchlengthLog > MLFSELog) return ERROR(dictionary_corrupted); - CHECK_E(FSE_buildDTable(entropy->MLTable, matchlengthNCount, matchlengthMaxValue, matchlengthLog), dictionary_corrupted); + RETURN_ERROR_IF(FSE_isError(matchlengthHeaderSize), dictionary_corrupted, ""); + RETURN_ERROR_IF(matchlengthMaxValue > MaxML, dictionary_corrupted, ""); + RETURN_ERROR_IF(matchlengthLog > MLFSELog, dictionary_corrupted, ""); + ZSTD_buildFSETable( entropy->MLTable, + matchlengthNCount, matchlengthMaxValue, + ML_base, ML_bits, + matchlengthLog); dictPtr += matchlengthHeaderSize; } { short litlengthNCount[MaxLL+1]; unsigned litlengthMaxValue = MaxLL, litlengthLog; size_t const litlengthHeaderSize = FSE_readNCount(litlengthNCount, &litlengthMaxValue, &litlengthLog, dictPtr, dictEnd-dictPtr); - if (FSE_isError(litlengthHeaderSize)) return ERROR(dictionary_corrupted); - if (litlengthLog > LLFSELog) return ERROR(dictionary_corrupted); - CHECK_E(FSE_buildDTable(entropy->LLTable, litlengthNCount, litlengthMaxValue, litlengthLog), dictionary_corrupted); + RETURN_ERROR_IF(FSE_isError(litlengthHeaderSize), dictionary_corrupted, ""); + RETURN_ERROR_IF(litlengthMaxValue > MaxLL, dictionary_corrupted, ""); + RETURN_ERROR_IF(litlengthLog > LLFSELog, dictionary_corrupted, ""); + ZSTD_buildFSETable( entropy->LLTable, + litlengthNCount, litlengthMaxValue, + LL_base, LL_bits, + litlengthLog); dictPtr += litlengthHeaderSize; } - if (dictPtr+12 > dictEnd) return ERROR(dictionary_corrupted); + RETURN_ERROR_IF(dictPtr+12 > dictEnd, dictionary_corrupted, ""); { int i; size_t const dictContentSize = (size_t)(dictEnd - (dictPtr+12)); for (i=0; i<3; i++) { U32 const rep = MEM_readLE32(dictPtr); dictPtr += 4; - if (rep==0 || rep >= dictContentSize) return ERROR(dictionary_corrupted); + RETURN_ERROR_IF(rep==0 || rep > dictContentSize, + dictionary_corrupted, ""); entropy->rep[i] = rep; } } @@ -1918,11 +1141,11 @@ static size_t ZSTD_decompress_insertDictionary(ZSTD_DCtx* dctx, const void* dict if (magic != ZSTD_MAGIC_DICTIONARY) { return ZSTD_refDictContent(dctx, dict, dictSize); /* pure content mode */ } } - dctx->dictID = MEM_readLE32((const char*)dict + 4); + dctx->dictID = MEM_readLE32((const char*)dict + ZSTD_FRAMEIDSIZE); /* load entropy tables */ - { size_t const eSize = ZSTD_loadEntropy(&dctx->entropy, dict, dictSize); - if (ZSTD_isError(eSize)) return ERROR(dictionary_corrupted); + { size_t const eSize = ZSTD_loadDEntropy(&dctx->entropy, dict, dictSize); + RETURN_ERROR_IF(ZSTD_isError(eSize), dictionary_corrupted, ""); dict = (const char*)dict + eSize; dictSize -= eSize; } @@ -1932,183 +1155,59 @@ static size_t ZSTD_decompress_insertDictionary(ZSTD_DCtx* dctx, const void* dict return ZSTD_refDictContent(dctx, dict, dictSize); } -size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx* dctx, const void* dict, size_t dictSize) -{ - CHECK_F( ZSTD_decompressBegin(dctx) ); - if (dict && dictSize) - CHECK_E(ZSTD_decompress_insertDictionary(dctx, dict, dictSize), dictionary_corrupted); - return 0; -} - - -/* ====== ZSTD_DDict ====== */ - -struct ZSTD_DDict_s { - void* dictBuffer; - const void* dictContent; - size_t dictSize; - ZSTD_entropyDTables_t entropy; - U32 dictID; - U32 entropyPresent; - ZSTD_customMem cMem; -}; /* typedef'd to ZSTD_DDict within "zstd.h" */ - -static const void* ZSTD_DDictDictContent(const ZSTD_DDict* ddict) -{ - return ddict->dictContent; -} - -static size_t ZSTD_DDictDictSize(const ZSTD_DDict* ddict) -{ - return ddict->dictSize; -} - -size_t ZSTD_decompressBegin_usingDDict(ZSTD_DCtx* dstDCtx, const ZSTD_DDict* ddict) -{ - CHECK_F( ZSTD_decompressBegin(dstDCtx) ); - if (ddict) { /* support begin on NULL */ - dstDCtx->dictID = ddict->dictID; - dstDCtx->base = ddict->dictContent; - dstDCtx->vBase = ddict->dictContent; - dstDCtx->dictEnd = (const BYTE*)ddict->dictContent + ddict->dictSize; - dstDCtx->previousDstEnd = dstDCtx->dictEnd; - if (ddict->entropyPresent) { - dstDCtx->litEntropy = 1; - dstDCtx->fseEntropy = 1; - dstDCtx->LLTptr = ddict->entropy.LLTable; - dstDCtx->MLTptr = ddict->entropy.MLTable; - dstDCtx->OFTptr = ddict->entropy.OFTable; - dstDCtx->HUFptr = ddict->entropy.hufTable; - dstDCtx->entropy.rep[0] = ddict->entropy.rep[0]; - dstDCtx->entropy.rep[1] = ddict->entropy.rep[1]; - dstDCtx->entropy.rep[2] = ddict->entropy.rep[2]; - } else { - dstDCtx->litEntropy = 0; - dstDCtx->fseEntropy = 0; - } - } - return 0; -} - -static size_t ZSTD_loadEntropy_inDDict(ZSTD_DDict* ddict) +size_t ZSTD_decompressBegin(ZSTD_DCtx* dctx) { - ddict->dictID = 0; - ddict->entropyPresent = 0; - if (ddict->dictSize < 8) return 0; - { U32 const magic = MEM_readLE32(ddict->dictContent); - if (magic != ZSTD_MAGIC_DICTIONARY) return 0; /* pure content mode */ - } - ddict->dictID = MEM_readLE32((const char*)ddict->dictContent + 4); - - /* load entropy tables */ - CHECK_E( ZSTD_loadEntropy(&ddict->entropy, ddict->dictContent, ddict->dictSize), dictionary_corrupted ); - ddict->entropyPresent = 1; + assert(dctx != NULL); + dctx->expected = ZSTD_startingInputLength(dctx->format); /* dctx->format must be properly set */ + dctx->stage = ZSTDds_getFrameHeaderSize; + dctx->decodedSize = 0; + dctx->previousDstEnd = NULL; + dctx->prefixStart = NULL; + dctx->virtualStart = NULL; + dctx->dictEnd = NULL; + dctx->entropy.hufTable[0] = (HUF_DTable)((HufLog)*0x1000001); /* cover both little and big endian */ + dctx->litEntropy = dctx->fseEntropy = 0; + dctx->dictID = 0; + dctx->bType = bt_reserved; + ZSTD_STATIC_ASSERT(sizeof(dctx->entropy.rep) == sizeof(repStartValue)); + memcpy(dctx->entropy.rep, repStartValue, sizeof(repStartValue)); /* initial repcodes */ + dctx->LLTptr = dctx->entropy.LLTable; + dctx->MLTptr = dctx->entropy.MLTable; + dctx->OFTptr = dctx->entropy.OFTable; + dctx->HUFptr = dctx->entropy.hufTable; return 0; } - -static size_t ZSTD_initDDict_internal(ZSTD_DDict* ddict, const void* dict, size_t dictSize, ZSTD_dictLoadMethod_e dictLoadMethod) +size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx* dctx, const void* dict, size_t dictSize) { - if ((dictLoadMethod == ZSTD_dlm_byRef) || (!dict) || (!dictSize)) { - ddict->dictBuffer = NULL; - ddict->dictContent = dict; - } else { - void* const internalBuffer = ZSTD_malloc(dictSize, ddict->cMem); - ddict->dictBuffer = internalBuffer; - ddict->dictContent = internalBuffer; - if (!internalBuffer) return ERROR(memory_allocation); - memcpy(internalBuffer, dict, dictSize); - } - ddict->dictSize = dictSize; - ddict->entropy.hufTable[0] = (HUF_DTable)((HufLog)*0x1000001); /* cover both little and big endian */ - - /* parse dictionary content */ - CHECK_F( ZSTD_loadEntropy_inDDict(ddict) ); - + FORWARD_IF_ERROR( ZSTD_decompressBegin(dctx) , ""); + if (dict && dictSize) + RETURN_ERROR_IF( + ZSTD_isError(ZSTD_decompress_insertDictionary(dctx, dict, dictSize)), + dictionary_corrupted, ""); return 0; } -ZSTD_DDict* ZSTD_createDDict_advanced(const void* dict, size_t dictSize, ZSTD_dictLoadMethod_e dictLoadMethod, ZSTD_customMem customMem) -{ - if (!customMem.customAlloc ^ !customMem.customFree) return NULL; - - { ZSTD_DDict* const ddict = (ZSTD_DDict*) ZSTD_malloc(sizeof(ZSTD_DDict), customMem); - if (!ddict) return NULL; - ddict->cMem = customMem; - - if (ZSTD_isError( ZSTD_initDDict_internal(ddict, dict, dictSize, dictLoadMethod) )) { - ZSTD_freeDDict(ddict); - return NULL; - } - - return ddict; - } -} - -/*! ZSTD_createDDict() : -* Create a digested dictionary, to start decompression without startup delay. -* `dict` content is copied inside DDict. -* Consequently, `dict` can be released after `ZSTD_DDict` creation */ -ZSTD_DDict* ZSTD_createDDict(const void* dict, size_t dictSize) -{ - ZSTD_customMem const allocator = { NULL, NULL, NULL }; - return ZSTD_createDDict_advanced(dict, dictSize, ZSTD_dlm_byCopy, allocator); -} - -/*! ZSTD_createDDict_byReference() : - * Create a digested dictionary, to start decompression without startup delay. - * Dictionary content is simply referenced, it will be accessed during decompression. - * Warning : dictBuffer must outlive DDict (DDict must be freed before dictBuffer) */ -ZSTD_DDict* ZSTD_createDDict_byReference(const void* dictBuffer, size_t dictSize) -{ - ZSTD_customMem const allocator = { NULL, NULL, NULL }; - return ZSTD_createDDict_advanced(dictBuffer, dictSize, ZSTD_dlm_byRef, allocator); -} +/* ====== ZSTD_DDict ====== */ -ZSTD_DDict* ZSTD_initStaticDDict(void* workspace, size_t workspaceSize, - const void* dict, size_t dictSize, - ZSTD_dictLoadMethod_e dictLoadMethod) +size_t ZSTD_decompressBegin_usingDDict(ZSTD_DCtx* dctx, const ZSTD_DDict* ddict) { - size_t const neededSpace = - sizeof(ZSTD_DDict) + (dictLoadMethod == ZSTD_dlm_byRef ? 0 : dictSize); - ZSTD_DDict* const ddict = (ZSTD_DDict*)workspace; - assert(workspace != NULL); - assert(dict != NULL); - if ((size_t)workspace & 7) return NULL; /* 8-aligned */ - if (workspaceSize < neededSpace) return NULL; - if (dictLoadMethod == ZSTD_dlm_byCopy) { - memcpy(ddict+1, dict, dictSize); /* local copy */ - dict = ddict+1; + DEBUGLOG(4, "ZSTD_decompressBegin_usingDDict"); + assert(dctx != NULL); + if (ddict) { + const char* const dictStart = (const char*)ZSTD_DDict_dictContent(ddict); + size_t const dictSize = ZSTD_DDict_dictSize(ddict); + const void* const dictEnd = dictStart + dictSize; + dctx->ddictIsCold = (dctx->dictEnd != dictEnd); + DEBUGLOG(4, "DDict is %s", + dctx->ddictIsCold ? "~cold~" : "hot!"); } - if (ZSTD_isError( ZSTD_initDDict_internal(ddict, dict, dictSize, ZSTD_dlm_byRef) )) - return NULL; - return ddict; -} - - -size_t ZSTD_freeDDict(ZSTD_DDict* ddict) -{ - if (ddict==NULL) return 0; /* support free on NULL */ - { ZSTD_customMem const cMem = ddict->cMem; - ZSTD_free(ddict->dictBuffer, cMem); - ZSTD_free(ddict, cMem); - return 0; + FORWARD_IF_ERROR( ZSTD_decompressBegin(dctx) , ""); + if (ddict) { /* NULL ddict is equivalent to no dictionary */ + ZSTD_copyDDictParameters(dctx, ddict); } -} - -/*! ZSTD_estimateDDictSize() : - * Estimate amount of memory that will be needed to create a dictionary for decompression. - * Note : dictionary created by reference using ZSTD_dlm_byRef are smaller */ -size_t ZSTD_estimateDDictSize(size_t dictSize, ZSTD_dictLoadMethod_e dictLoadMethod) -{ - return sizeof(ZSTD_DDict) + (dictLoadMethod == ZSTD_dlm_byRef ? 0 : dictSize); -} - -size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict) -{ - if (ddict==NULL) return 0; /* support sizeof on NULL */ - return sizeof(*ddict) + (ddict->dictBuffer ? ddict->dictSize : 0) ; + return 0; } /*! ZSTD_getDictID_fromDict() : @@ -2119,21 +1218,11 @@ unsigned ZSTD_getDictID_fromDict(const void* dict, size_t dictSize) { if (dictSize < 8) return 0; if (MEM_readLE32(dict) != ZSTD_MAGIC_DICTIONARY) return 0; - return MEM_readLE32((const char*)dict + 4); -} - -/*! ZSTD_getDictID_fromDDict() : - * Provides the dictID of the dictionary loaded into `ddict`. - * If @return == 0, the dictionary is not conformant to Zstandard specification, or empty. - * Non-conformant dictionaries can still be loaded, but as content-only dictionaries. */ -unsigned ZSTD_getDictID_fromDDict(const ZSTD_DDict* ddict) -{ - if (ddict==NULL) return 0; - return ZSTD_getDictID_fromDict(ddict->dictContent, ddict->dictSize); + return MEM_readLE32((const char*)dict + ZSTD_FRAMEIDSIZE); } /*! ZSTD_getDictID_fromFrame() : - * Provides the dictID required to decompresse frame stored within `src`. + * Provides the dictID required to decompress frame stored within `src`. * If @return == 0, the dictID could not be decoded. * This could for one of the following reasons : * - The frame does not require a dictionary (most common case). @@ -2175,6 +1264,7 @@ size_t ZSTD_decompress_usingDDict(ZSTD_DCtx* dctx, ZSTD_DStream* ZSTD_createDStream(void) { + DEBUGLOG(3, "ZSTD_createDStream"); return ZSTD_createDStream_advanced(ZSTD_defaultCMem); } @@ -2194,64 +1284,201 @@ size_t ZSTD_freeDStream(ZSTD_DStream* zds) } -/* *** Initialization *** */ +/* *** Initialization *** */ size_t ZSTD_DStreamInSize(void) { return ZSTD_BLOCKSIZE_MAX + ZSTD_blockHeaderSize; } size_t ZSTD_DStreamOutSize(void) { return ZSTD_BLOCKSIZE_MAX; } +size_t ZSTD_DCtx_loadDictionary_advanced(ZSTD_DCtx* dctx, + const void* dict, size_t dictSize, + ZSTD_dictLoadMethod_e dictLoadMethod, + ZSTD_dictContentType_e dictContentType) +{ + RETURN_ERROR_IF(dctx->streamStage != zdss_init, stage_wrong, ""); + ZSTD_clearDict(dctx); + if (dict && dictSize != 0) { + dctx->ddictLocal = ZSTD_createDDict_advanced(dict, dictSize, dictLoadMethod, dictContentType, dctx->customMem); + RETURN_ERROR_IF(dctx->ddictLocal == NULL, memory_allocation, "NULL pointer!"); + dctx->ddict = dctx->ddictLocal; + dctx->dictUses = ZSTD_use_indefinitely; + } + return 0; +} + +size_t ZSTD_DCtx_loadDictionary_byReference(ZSTD_DCtx* dctx, const void* dict, size_t dictSize) +{ + return ZSTD_DCtx_loadDictionary_advanced(dctx, dict, dictSize, ZSTD_dlm_byRef, ZSTD_dct_auto); +} + +size_t ZSTD_DCtx_loadDictionary(ZSTD_DCtx* dctx, const void* dict, size_t dictSize) +{ + return ZSTD_DCtx_loadDictionary_advanced(dctx, dict, dictSize, ZSTD_dlm_byCopy, ZSTD_dct_auto); +} + +size_t ZSTD_DCtx_refPrefix_advanced(ZSTD_DCtx* dctx, const void* prefix, size_t prefixSize, ZSTD_dictContentType_e dictContentType) +{ + FORWARD_IF_ERROR(ZSTD_DCtx_loadDictionary_advanced(dctx, prefix, prefixSize, ZSTD_dlm_byRef, dictContentType), ""); + dctx->dictUses = ZSTD_use_once; + return 0; +} + +size_t ZSTD_DCtx_refPrefix(ZSTD_DCtx* dctx, const void* prefix, size_t prefixSize) +{ + return ZSTD_DCtx_refPrefix_advanced(dctx, prefix, prefixSize, ZSTD_dct_rawContent); +} + + +/* ZSTD_initDStream_usingDict() : + * return : expected size, aka ZSTD_startingInputLength(). + * this function cannot fail */ size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize) { - zds->streamStage = zdss_loadHeader; - zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0; - ZSTD_freeDDict(zds->ddictLocal); - if (dict && dictSize >= 8) { - zds->ddictLocal = ZSTD_createDDict(dict, dictSize); - if (zds->ddictLocal == NULL) return ERROR(memory_allocation); - } else zds->ddictLocal = NULL; - zds->ddict = zds->ddictLocal; - zds->legacyVersion = 0; - zds->hostageByte = 0; - return ZSTD_frameHeaderSize_prefix; + DEBUGLOG(4, "ZSTD_initDStream_usingDict"); + FORWARD_IF_ERROR( ZSTD_DCtx_reset(zds, ZSTD_reset_session_only) , ""); + FORWARD_IF_ERROR( ZSTD_DCtx_loadDictionary(zds, dict, dictSize) , ""); + return ZSTD_startingInputLength(zds->format); } +/* note : this variant can't fail */ size_t ZSTD_initDStream(ZSTD_DStream* zds) { - return ZSTD_initDStream_usingDict(zds, NULL, 0); + DEBUGLOG(4, "ZSTD_initDStream"); + return ZSTD_initDStream_usingDDict(zds, NULL); } /* ZSTD_initDStream_usingDDict() : - * ddict will just be referenced, and must outlive decompression session */ -size_t ZSTD_initDStream_usingDDict(ZSTD_DStream* zds, const ZSTD_DDict* ddict) + * ddict will just be referenced, and must outlive decompression session + * this function cannot fail */ +size_t ZSTD_initDStream_usingDDict(ZSTD_DStream* dctx, const ZSTD_DDict* ddict) { - size_t const initResult = ZSTD_initDStream(zds); - zds->ddict = ddict; - return initResult; + FORWARD_IF_ERROR( ZSTD_DCtx_reset(dctx, ZSTD_reset_session_only) , ""); + FORWARD_IF_ERROR( ZSTD_DCtx_refDDict(dctx, ddict) , ""); + return ZSTD_startingInputLength(dctx->format); } -size_t ZSTD_resetDStream(ZSTD_DStream* zds) +/* ZSTD_resetDStream() : + * return : expected size, aka ZSTD_startingInputLength(). + * this function cannot fail */ +size_t ZSTD_resetDStream(ZSTD_DStream* dctx) { - zds->streamStage = zdss_loadHeader; - zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0; - zds->legacyVersion = 0; - zds->hostageByte = 0; - return ZSTD_frameHeaderSize_prefix; + FORWARD_IF_ERROR(ZSTD_DCtx_reset(dctx, ZSTD_reset_session_only), ""); + return ZSTD_startingInputLength(dctx->format); } -size_t ZSTD_setDStreamParameter(ZSTD_DStream* zds, - ZSTD_DStreamParameter_e paramType, unsigned paramValue) + +size_t ZSTD_DCtx_refDDict(ZSTD_DCtx* dctx, const ZSTD_DDict* ddict) { - switch(paramType) - { - default : return ERROR(parameter_unsupported); - case DStream_p_maxWindowSize : zds->maxWindowSize = paramValue ? paramValue : (U32)(-1); break; + RETURN_ERROR_IF(dctx->streamStage != zdss_init, stage_wrong, ""); + ZSTD_clearDict(dctx); + if (ddict) { + dctx->ddict = ddict; + dctx->dictUses = ZSTD_use_indefinitely; + } + return 0; +} + +/* ZSTD_DCtx_setMaxWindowSize() : + * note : no direct equivalence in ZSTD_DCtx_setParameter, + * since this version sets windowSize, and the other sets windowLog */ +size_t ZSTD_DCtx_setMaxWindowSize(ZSTD_DCtx* dctx, size_t maxWindowSize) +{ + ZSTD_bounds const bounds = ZSTD_dParam_getBounds(ZSTD_d_windowLogMax); + size_t const min = (size_t)1 << bounds.lowerBound; + size_t const max = (size_t)1 << bounds.upperBound; + RETURN_ERROR_IF(dctx->streamStage != zdss_init, stage_wrong, ""); + RETURN_ERROR_IF(maxWindowSize < min, parameter_outOfBound, ""); + RETURN_ERROR_IF(maxWindowSize > max, parameter_outOfBound, ""); + dctx->maxWindowSize = maxWindowSize; + return 0; +} + +size_t ZSTD_DCtx_setFormat(ZSTD_DCtx* dctx, ZSTD_format_e format) +{ + return ZSTD_DCtx_setParameter(dctx, ZSTD_d_format, format); +} + +ZSTD_bounds ZSTD_dParam_getBounds(ZSTD_dParameter dParam) +{ + ZSTD_bounds bounds = { 0, 0, 0 }; + switch(dParam) { + case ZSTD_d_windowLogMax: + bounds.lowerBound = ZSTD_WINDOWLOG_ABSOLUTEMIN; + bounds.upperBound = ZSTD_WINDOWLOG_MAX; + return bounds; + case ZSTD_d_format: + bounds.lowerBound = (int)ZSTD_f_zstd1; + bounds.upperBound = (int)ZSTD_f_zstd1_magicless; + ZSTD_STATIC_ASSERT(ZSTD_f_zstd1 < ZSTD_f_zstd1_magicless); + return bounds; + case ZSTD_d_stableOutBuffer: + bounds.lowerBound = (int)ZSTD_obm_buffered; + bounds.upperBound = (int)ZSTD_obm_stable; + return bounds; + default:; + } + bounds.error = ERROR(parameter_unsupported); + return bounds; +} + +/* ZSTD_dParam_withinBounds: + * @return 1 if value is within dParam bounds, + * 0 otherwise */ +static int ZSTD_dParam_withinBounds(ZSTD_dParameter dParam, int value) +{ + ZSTD_bounds const bounds = ZSTD_dParam_getBounds(dParam); + if (ZSTD_isError(bounds.error)) return 0; + if (value < bounds.lowerBound) return 0; + if (value > bounds.upperBound) return 0; + return 1; +} + +#define CHECK_DBOUNDS(p,v) { \ + RETURN_ERROR_IF(!ZSTD_dParam_withinBounds(p, v), parameter_outOfBound, ""); \ +} + +size_t ZSTD_DCtx_setParameter(ZSTD_DCtx* dctx, ZSTD_dParameter dParam, int value) +{ + RETURN_ERROR_IF(dctx->streamStage != zdss_init, stage_wrong, ""); + switch(dParam) { + case ZSTD_d_windowLogMax: + if (value == 0) value = ZSTD_WINDOWLOG_LIMIT_DEFAULT; + CHECK_DBOUNDS(ZSTD_d_windowLogMax, value); + dctx->maxWindowSize = ((size_t)1) << value; + return 0; + case ZSTD_d_format: + CHECK_DBOUNDS(ZSTD_d_format, value); + dctx->format = (ZSTD_format_e)value; + return 0; + case ZSTD_d_stableOutBuffer: + CHECK_DBOUNDS(ZSTD_d_stableOutBuffer, value); + dctx->outBufferMode = (ZSTD_outBufferMode_e)value; + return 0; + default:; + } + RETURN_ERROR(parameter_unsupported, ""); +} + +size_t ZSTD_DCtx_reset(ZSTD_DCtx* dctx, ZSTD_ResetDirective reset) +{ + if ( (reset == ZSTD_reset_session_only) + || (reset == ZSTD_reset_session_and_parameters) ) { + dctx->streamStage = zdss_init; + dctx->noForwardProgress = 0; + } + if ( (reset == ZSTD_reset_parameters) + || (reset == ZSTD_reset_session_and_parameters) ) { + RETURN_ERROR_IF(dctx->streamStage != zdss_init, stage_wrong, ""); + ZSTD_clearDict(dctx); + dctx->format = ZSTD_f_zstd1; + dctx->maxWindowSize = ZSTD_MAXWINDOWSIZE_DEFAULT; } return 0; } -size_t ZSTD_sizeof_DStream(const ZSTD_DStream* zds) +size_t ZSTD_sizeof_DStream(const ZSTD_DStream* dctx) { - return ZSTD_sizeof_DCtx(zds); + return ZSTD_sizeof_DCtx(dctx); } size_t ZSTD_decodingBufferSize_min(unsigned long long windowSize, unsigned long long frameContentSize) @@ -2260,7 +1487,8 @@ size_t ZSTD_decodingBufferSize_min(unsigned long long windowSize, unsigned long unsigned long long const neededRBSize = windowSize + blockSize + (WILDCOPY_OVERLENGTH * 2); unsigned long long const neededSize = MIN(frameContentSize, neededRBSize); size_t const minRBSize = (size_t) neededSize; - if ((unsigned long long)minRBSize != neededSize) return ERROR(frameParameter_windowTooLarge); + RETURN_ERROR_IF((unsigned long long)minRBSize != neededSize, + frameParameter_windowTooLarge, ""); return minRBSize; } @@ -2272,84 +1500,174 @@ size_t ZSTD_estimateDStreamSize(size_t windowSize) return ZSTD_estimateDCtxSize() + inBuffSize + outBuffSize; } -ZSTDLIB_API size_t ZSTD_estimateDStreamSize_fromFrame(const void* src, size_t srcSize) +size_t ZSTD_estimateDStreamSize_fromFrame(const void* src, size_t srcSize) { - U32 const windowSizeMax = 1U << ZSTD_WINDOWLOG_MAX; /* note : should be user-selectable */ + U32 const windowSizeMax = 1U << ZSTD_WINDOWLOG_MAX; /* note : should be user-selectable, but requires an additional parameter (or a dctx) */ ZSTD_frameHeader zfh; size_t const err = ZSTD_getFrameHeader(&zfh, src, srcSize); if (ZSTD_isError(err)) return err; - if (err>0) return ERROR(srcSize_wrong); - if (zfh.windowSize > windowSizeMax) - return ERROR(frameParameter_windowTooLarge); + RETURN_ERROR_IF(err>0, srcSize_wrong, ""); + RETURN_ERROR_IF(zfh.windowSize > windowSizeMax, + frameParameter_windowTooLarge, ""); return ZSTD_estimateDStreamSize((size_t)zfh.windowSize); } /* ***** Decompression ***** */ -MEM_STATIC size_t ZSTD_limitCopy(void* dst, size_t dstCapacity, const void* src, size_t srcSize) +static int ZSTD_DCtx_isOverflow(ZSTD_DStream* zds, size_t const neededInBuffSize, size_t const neededOutBuffSize) { - size_t const length = MIN(dstCapacity, srcSize); - memcpy(dst, src, length); - return length; + return (zds->inBuffSize + zds->outBuffSize) >= (neededInBuffSize + neededOutBuffSize) * ZSTD_WORKSPACETOOLARGE_FACTOR; } +static void ZSTD_DCtx_updateOversizedDuration(ZSTD_DStream* zds, size_t const neededInBuffSize, size_t const neededOutBuffSize) +{ + if (ZSTD_DCtx_isOverflow(zds, neededInBuffSize, neededOutBuffSize)) + zds->oversizedDuration++; + else + zds->oversizedDuration = 0; +} + +static int ZSTD_DCtx_isOversizedTooLong(ZSTD_DStream* zds) +{ + return zds->oversizedDuration >= ZSTD_WORKSPACETOOLARGE_MAXDURATION; +} + +/* Checks that the output buffer hasn't changed if ZSTD_obm_stable is used. */ +static size_t ZSTD_checkOutBuffer(ZSTD_DStream const* zds, ZSTD_outBuffer const* output) +{ + ZSTD_outBuffer const expect = zds->expectedOutBuffer; + /* No requirement when ZSTD_obm_stable is not enabled. */ + if (zds->outBufferMode != ZSTD_obm_stable) + return 0; + /* Any buffer is allowed in zdss_init, this must be the same for every other call until + * the context is reset. + */ + if (zds->streamStage == zdss_init) + return 0; + /* The buffer must match our expectation exactly. */ + if (expect.dst == output->dst && expect.pos == output->pos && expect.size == output->size) + return 0; + RETURN_ERROR(dstBuffer_wrong, "ZSTD_obm_stable enabled but output differs!"); +} + +/* Calls ZSTD_decompressContinue() with the right parameters for ZSTD_decompressStream() + * and updates the stage and the output buffer state. This call is extracted so it can be + * used both when reading directly from the ZSTD_inBuffer, and in buffered input mode. + * NOTE: You must break after calling this function since the streamStage is modified. + */ +static size_t ZSTD_decompressContinueStream( + ZSTD_DStream* zds, char** op, char* oend, + void const* src, size_t srcSize) { + int const isSkipFrame = ZSTD_isSkipFrame(zds); + if (zds->outBufferMode == ZSTD_obm_buffered) { + size_t const dstSize = isSkipFrame ? 0 : zds->outBuffSize - zds->outStart; + size_t const decodedSize = ZSTD_decompressContinue(zds, + zds->outBuff + zds->outStart, dstSize, src, srcSize); + FORWARD_IF_ERROR(decodedSize, ""); + if (!decodedSize && !isSkipFrame) { + zds->streamStage = zdss_read; + } else { + zds->outEnd = zds->outStart + decodedSize; + zds->streamStage = zdss_flush; + } + } else { + /* Write directly into the output buffer */ + size_t const dstSize = isSkipFrame ? 0 : oend - *op; + size_t const decodedSize = ZSTD_decompressContinue(zds, *op, dstSize, src, srcSize); + FORWARD_IF_ERROR(decodedSize, ""); + *op += decodedSize; + /* Flushing is not needed. */ + zds->streamStage = zdss_read; + assert(*op <= oend); + assert(zds->outBufferMode == ZSTD_obm_stable); + } + return 0; +} size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inBuffer* input) { - const char* const istart = (const char*)(input->src) + input->pos; - const char* const iend = (const char*)(input->src) + input->size; + const char* const src = (const char*)input->src; + const char* const istart = input->pos != 0 ? src + input->pos : src; + const char* const iend = input->size != 0 ? src + input->size : src; const char* ip = istart; - char* const ostart = (char*)(output->dst) + output->pos; - char* const oend = (char*)(output->dst) + output->size; + char* const dst = (char*)output->dst; + char* const ostart = output->pos != 0 ? dst + output->pos : dst; + char* const oend = output->size != 0 ? dst + output->size : dst; char* op = ostart; U32 someMoreWork = 1; DEBUGLOG(5, "ZSTD_decompressStream"); + RETURN_ERROR_IF( + input->pos > input->size, + srcSize_wrong, + "forbidden. in: pos: %u vs size: %u", + (U32)input->pos, (U32)input->size); + RETURN_ERROR_IF( + output->pos > output->size, + dstSize_tooSmall, + "forbidden. out: pos: %u vs size: %u", + (U32)output->pos, (U32)output->size); DEBUGLOG(5, "input size : %u", (U32)(input->size - input->pos)); -#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT>=1) - if (zds->legacyVersion) { - /* legacy support is incompatible with static dctx */ - if (zds->staticSize) return ERROR(memory_allocation); - return ZSTD_decompressLegacyStream(zds->legacyContext, zds->legacyVersion, output, input); - } -#endif + FORWARD_IF_ERROR(ZSTD_checkOutBuffer(zds, output), ""); while (someMoreWork) { switch(zds->streamStage) { case zdss_init : - ZSTD_resetDStream(zds); /* transparent reset on starting decoding a new frame */ + DEBUGLOG(5, "stage zdss_init => transparent reset "); + zds->streamStage = zdss_loadHeader; + zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0; + zds->legacyVersion = 0; + zds->hostageByte = 0; + zds->expectedOutBuffer = *output; /* fall-through */ case zdss_loadHeader : - { size_t const hSize = ZSTD_getFrameHeader(&zds->fParams, zds->headerBuffer, zds->lhSize); + DEBUGLOG(5, "stage zdss_loadHeader (srcSize : %u)", (U32)(iend - ip)); +#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT>=1) + if (zds->legacyVersion) { + RETURN_ERROR_IF(zds->staticSize, memory_allocation, + "legacy support is incompatible with static dctx"); + { size_t const hint = ZSTD_decompressLegacyStream(zds->legacyContext, zds->legacyVersion, output, input); + if (hint==0) zds->streamStage = zdss_init; + return hint; + } } +#endif + { size_t const hSize = ZSTD_getFrameHeader_advanced(&zds->fParams, zds->headerBuffer, zds->lhSize, zds->format); + DEBUGLOG(5, "header size : %u", (U32)hSize); if (ZSTD_isError(hSize)) { #if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT>=1) U32 const legacyVersion = ZSTD_isLegacy(istart, iend-istart); if (legacyVersion) { - const void* const dict = zds->ddict ? zds->ddict->dictContent : NULL; - size_t const dictSize = zds->ddict ? zds->ddict->dictSize : 0; - /* legacy support is incompatible with static dctx */ - if (zds->staticSize) return ERROR(memory_allocation); - CHECK_F(ZSTD_initLegacyStream(&zds->legacyContext, + ZSTD_DDict const* const ddict = ZSTD_getDDict(zds); + const void* const dict = ddict ? ZSTD_DDict_dictContent(ddict) : NULL; + size_t const dictSize = ddict ? ZSTD_DDict_dictSize(ddict) : 0; + DEBUGLOG(5, "ZSTD_decompressStream: detected legacy version v0.%u", legacyVersion); + RETURN_ERROR_IF(zds->staticSize, memory_allocation, + "legacy support is incompatible with static dctx"); + FORWARD_IF_ERROR(ZSTD_initLegacyStream(&zds->legacyContext, zds->previousLegacyVersion, legacyVersion, - dict, dictSize)); + dict, dictSize), ""); zds->legacyVersion = zds->previousLegacyVersion = legacyVersion; - return ZSTD_decompressLegacyStream(zds->legacyContext, legacyVersion, output, input); - } + { size_t const hint = ZSTD_decompressLegacyStream(zds->legacyContext, legacyVersion, output, input); + if (hint==0) zds->streamStage = zdss_init; /* or stay in stage zdss_loadHeader */ + return hint; + } } #endif - return hSize; /* error */ + return hSize; /* error */ } if (hSize != 0) { /* need more input */ size_t const toLoad = hSize - zds->lhSize; /* if hSize!=0, hSize > zds->lhSize */ - if (toLoad > (size_t)(iend-ip)) { /* not enough input to load full header */ - if (iend-ip > 0) { - memcpy(zds->headerBuffer + zds->lhSize, ip, iend-ip); - zds->lhSize += iend-ip; + size_t const remainingInput = (size_t)(iend-ip); + assert(iend >= ip); + if (toLoad > remainingInput) { /* not enough input to load full header */ + if (remainingInput > 0) { + memcpy(zds->headerBuffer + zds->lhSize, ip, remainingInput); + zds->lhSize += remainingInput; } input->pos = input->size; - return (MAX(ZSTD_frameHeaderSize_min, hSize) - zds->lhSize) + ZSTD_blockHeaderSize; /* remaining header bytes + next block header */ + return (MAX((size_t)ZSTD_FRAMEHEADERSIZE_MIN(zds->format), hSize) - zds->lhSize) + ZSTD_blockHeaderSize; /* remaining header bytes + next block header */ } assert(ip != NULL); memcpy(zds->headerBuffer + zds->lhSize, ip, toLoad); zds->lhSize = hSize; ip += toLoad; @@ -2357,12 +1675,15 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB } } /* check for single-pass mode opportunity */ - if (zds->fParams.frameContentSize && zds->fParams.windowSize /* skippable frame if == 0 */ + if (zds->fParams.frameContentSize != ZSTD_CONTENTSIZE_UNKNOWN + && zds->fParams.frameType != ZSTD_skippableFrame && (U64)(size_t)(oend-op) >= zds->fParams.frameContentSize) { size_t const cSize = ZSTD_findFrameCompressedSize(istart, iend-istart); if (cSize <= (size_t)(iend-istart)) { - size_t const decompressedSize = ZSTD_decompress_usingDDict(zds, op, oend-op, istart, cSize, zds->ddict); + /* shortcut : using single-pass mode */ + size_t const decompressedSize = ZSTD_decompress_usingDDict(zds, op, oend-op, istart, cSize, ZSTD_getDDict(zds)); if (ZSTD_isError(decompressedSize)) return decompressedSize; + DEBUGLOG(4, "shortcut to single-pass ZSTD_decompress_usingDDict()") ip = istart + cSize; op += decompressedSize; zds->expected = 0; @@ -2371,55 +1692,75 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB break; } } + /* Check output buffer is large enough for ZSTD_odm_stable. */ + if (zds->outBufferMode == ZSTD_obm_stable + && zds->fParams.frameType != ZSTD_skippableFrame + && zds->fParams.frameContentSize != ZSTD_CONTENTSIZE_UNKNOWN + && (U64)(size_t)(oend-op) < zds->fParams.frameContentSize) { + RETURN_ERROR(dstSize_tooSmall, "ZSTD_obm_stable passed but ZSTD_outBuffer is too small"); + } + /* Consume header (see ZSTDds_decodeFrameHeader) */ DEBUGLOG(4, "Consume header"); - CHECK_F(ZSTD_decompressBegin_usingDDict(zds, zds->ddict)); + FORWARD_IF_ERROR(ZSTD_decompressBegin_usingDDict(zds, ZSTD_getDDict(zds)), ""); - if ((MEM_readLE32(zds->headerBuffer) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { /* skippable frame */ - zds->expected = MEM_readLE32(zds->headerBuffer + 4); + if ((MEM_readLE32(zds->headerBuffer) & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) { /* skippable frame */ + zds->expected = MEM_readLE32(zds->headerBuffer + ZSTD_FRAMEIDSIZE); zds->stage = ZSTDds_skipFrame; } else { - CHECK_F(ZSTD_decodeFrameHeader(zds, zds->headerBuffer, zds->lhSize)); + FORWARD_IF_ERROR(ZSTD_decodeFrameHeader(zds, zds->headerBuffer, zds->lhSize), ""); zds->expected = ZSTD_blockHeaderSize; zds->stage = ZSTDds_decodeBlockHeader; } /* control buffer memory usage */ - DEBUGLOG(4, "Control max buffer memory usage"); + DEBUGLOG(4, "Control max memory usage (%u KB <= max %u KB)", + (U32)(zds->fParams.windowSize >>10), + (U32)(zds->maxWindowSize >> 10) ); zds->fParams.windowSize = MAX(zds->fParams.windowSize, 1U << ZSTD_WINDOWLOG_ABSOLUTEMIN); - if (zds->fParams.windowSize > zds->maxWindowSize) return ERROR(frameParameter_windowTooLarge); + RETURN_ERROR_IF(zds->fParams.windowSize > zds->maxWindowSize, + frameParameter_windowTooLarge, ""); /* Adapt buffer sizes to frame header instructions */ { size_t const neededInBuffSize = MAX(zds->fParams.blockSizeMax, 4 /* frame checksum */); - size_t const neededOutBuffSize = ZSTD_decodingBufferSize_min(zds->fParams.windowSize, zds->fParams.frameContentSize); - if ((zds->inBuffSize < neededInBuffSize) || (zds->outBuffSize < neededOutBuffSize)) { - size_t const bufferSize = neededInBuffSize + neededOutBuffSize; - DEBUGLOG(4, "inBuff : from %u to %u", - (U32)zds->inBuffSize, (U32)neededInBuffSize); - DEBUGLOG(4, "outBuff : from %u to %u", - (U32)zds->outBuffSize, (U32)neededOutBuffSize); - if (zds->staticSize) { /* static DCtx */ - DEBUGLOG(4, "staticSize : %u", (U32)zds->staticSize); - assert(zds->staticSize >= sizeof(ZSTD_DCtx)); /* controlled at init */ - if (bufferSize > zds->staticSize - sizeof(ZSTD_DCtx)) - return ERROR(memory_allocation); - } else { - ZSTD_free(zds->inBuff, zds->customMem); - zds->inBuffSize = 0; - zds->outBuffSize = 0; - zds->inBuff = (char*)ZSTD_malloc(bufferSize, zds->customMem); - if (zds->inBuff == NULL) return ERROR(memory_allocation); - } - zds->inBuffSize = neededInBuffSize; - zds->outBuff = zds->inBuff + zds->inBuffSize; - zds->outBuffSize = neededOutBuffSize; - } } + size_t const neededOutBuffSize = zds->outBufferMode == ZSTD_obm_buffered + ? ZSTD_decodingBufferSize_min(zds->fParams.windowSize, zds->fParams.frameContentSize) + : 0; + + ZSTD_DCtx_updateOversizedDuration(zds, neededInBuffSize, neededOutBuffSize); + + { int const tooSmall = (zds->inBuffSize < neededInBuffSize) || (zds->outBuffSize < neededOutBuffSize); + int const tooLarge = ZSTD_DCtx_isOversizedTooLong(zds); + + if (tooSmall || tooLarge) { + size_t const bufferSize = neededInBuffSize + neededOutBuffSize; + DEBUGLOG(4, "inBuff : from %u to %u", + (U32)zds->inBuffSize, (U32)neededInBuffSize); + DEBUGLOG(4, "outBuff : from %u to %u", + (U32)zds->outBuffSize, (U32)neededOutBuffSize); + if (zds->staticSize) { /* static DCtx */ + DEBUGLOG(4, "staticSize : %u", (U32)zds->staticSize); + assert(zds->staticSize >= sizeof(ZSTD_DCtx)); /* controlled at init */ + RETURN_ERROR_IF( + bufferSize > zds->staticSize - sizeof(ZSTD_DCtx), + memory_allocation, ""); + } else { + ZSTD_free(zds->inBuff, zds->customMem); + zds->inBuffSize = 0; + zds->outBuffSize = 0; + zds->inBuff = (char*)ZSTD_malloc(bufferSize, zds->customMem); + RETURN_ERROR_IF(zds->inBuff == NULL, memory_allocation, ""); + } + zds->inBuffSize = neededInBuffSize; + zds->outBuff = zds->inBuff + zds->inBuffSize; + zds->outBuffSize = neededOutBuffSize; + } } } zds->streamStage = zdss_read; /* fall-through */ case zdss_read: DEBUGLOG(5, "stage zdss_read"); - { size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds); + { size_t const neededInSize = ZSTD_nextSrcSizeToDecompressWithInputSize(zds, iend - ip); DEBUGLOG(5, "neededInSize = %u", (U32)neededInSize); if (neededInSize==0) { /* end of frame */ zds->streamStage = zdss_init; @@ -2427,42 +1768,40 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB break; } if ((size_t)(iend-ip) >= neededInSize) { /* decode directly from src */ - int const isSkipFrame = ZSTD_isSkipFrame(zds); - size_t const decodedSize = ZSTD_decompressContinue(zds, - zds->outBuff + zds->outStart, (isSkipFrame ? 0 : zds->outBuffSize - zds->outStart), - ip, neededInSize); - if (ZSTD_isError(decodedSize)) return decodedSize; + FORWARD_IF_ERROR(ZSTD_decompressContinueStream(zds, &op, oend, ip, neededInSize), ""); ip += neededInSize; - if (!decodedSize && !isSkipFrame) break; /* this was just a header */ - zds->outEnd = zds->outStart + decodedSize; - zds->streamStage = zdss_flush; + /* Function modifies the stage so we must break */ break; } } if (ip==iend) { someMoreWork = 0; break; } /* no more input */ zds->streamStage = zdss_load; /* fall-through */ + case zdss_load: { size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds); - size_t const toLoad = neededInSize - zds->inPos; /* should always be <= remaining space within inBuff */ + size_t const toLoad = neededInSize - zds->inPos; + int const isSkipFrame = ZSTD_isSkipFrame(zds); size_t loadedSize; - if (toLoad > zds->inBuffSize - zds->inPos) return ERROR(corruption_detected); /* should never happen */ - loadedSize = ZSTD_limitCopy(zds->inBuff + zds->inPos, toLoad, ip, iend-ip); + /* At this point we shouldn't be decompressing a block that we can stream. */ + assert(neededInSize == ZSTD_nextSrcSizeToDecompressWithInputSize(zds, iend - ip)); + if (isSkipFrame) { + loadedSize = MIN(toLoad, (size_t)(iend-ip)); + } else { + RETURN_ERROR_IF(toLoad > zds->inBuffSize - zds->inPos, + corruption_detected, + "should never happen"); + loadedSize = ZSTD_limitCopy(zds->inBuff + zds->inPos, toLoad, ip, iend-ip); + } ip += loadedSize; zds->inPos += loadedSize; if (loadedSize < toLoad) { someMoreWork = 0; break; } /* not enough input, wait for more */ /* decode loaded input */ - { const int isSkipFrame = ZSTD_isSkipFrame(zds); - size_t const decodedSize = ZSTD_decompressContinue(zds, - zds->outBuff + zds->outStart, zds->outBuffSize - zds->outStart, - zds->inBuff, neededInSize); - if (ZSTD_isError(decodedSize)) return decodedSize; - zds->inPos = 0; /* input is consumed */ - if (!decodedSize && !isSkipFrame) { zds->streamStage = zdss_read; break; } /* this was just a header */ - zds->outEnd = zds->outStart + decodedSize; - } } - zds->streamStage = zdss_flush; - /* fall-through */ + zds->inPos = 0; /* input is consumed */ + FORWARD_IF_ERROR(ZSTD_decompressContinueStream(zds, &op, oend, zds->inBuff, neededInSize), ""); + /* Function modifies the stage so we must break */ + break; + } case zdss_flush: { size_t const toFlushSize = zds->outEnd - zds->outStart; size_t const flushedSize = ZSTD_limitCopy(op, oend-op, zds->outBuff + zds->outStart, toFlushSize); @@ -2483,12 +1822,28 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB someMoreWork = 0; break; - default: return ERROR(GENERIC); /* impossible */ + default: + assert(0); /* impossible */ + RETURN_ERROR(GENERIC, "impossible to reach"); /* some compiler require default to do something */ } } /* result */ - input->pos += (size_t)(ip-istart); - output->pos += (size_t)(op-ostart); + input->pos = (size_t)(ip - (const char*)(input->src)); + output->pos = (size_t)(op - (char*)(output->dst)); + + /* Update the expected output buffer for ZSTD_obm_stable. */ + zds->expectedOutBuffer = *output; + + if ((ip==istart) && (op==ostart)) { /* no forward progress */ + zds->noForwardProgress ++; + if (zds->noForwardProgress >= ZSTD_NO_FORWARD_PROGRESS_MAX) { + RETURN_ERROR_IF(op==oend, dstSize_tooSmall, ""); + RETURN_ERROR_IF(ip==iend, srcSize_wrong, ""); + assert(0); + } + } else { + zds->noForwardProgress = 0; + } { size_t nextSrcSizeHint = ZSTD_nextSrcSizeToDecompress(zds); if (!nextSrcSizeHint) { /* frame fully decoded */ if (zds->outEnd == zds->outStart) { /* output fully flushed */ @@ -2509,8 +1864,22 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB return 1; } /* nextSrcSizeHint==0 */ nextSrcSizeHint += ZSTD_blockHeaderSize * (ZSTD_nextInputType(zds) == ZSTDnit_block); /* preload header of next block */ - if (zds->inPos > nextSrcSizeHint) return ERROR(GENERIC); /* should never happen */ - nextSrcSizeHint -= zds->inPos; /* already loaded*/ + assert(zds->inPos <= nextSrcSizeHint); + nextSrcSizeHint -= zds->inPos; /* part already loaded*/ return nextSrcSizeHint; } } + +size_t ZSTD_decompressStream_simpleArgs ( + ZSTD_DCtx* dctx, + void* dst, size_t dstCapacity, size_t* dstPos, + const void* src, size_t srcSize, size_t* srcPos) +{ + ZSTD_outBuffer output = { dst, dstCapacity, *dstPos }; + ZSTD_inBuffer input = { src, srcSize, *srcPos }; + /* ZSTD_compress_generic() will check validity of dstPos and srcPos */ + size_t const cErr = ZSTD_decompressStream(dctx, &output, &input); + *dstPos = output.pos; + *srcPos = input.pos; + return cErr; +} |