Merge pull request #2278 from senhuang42/ignore_checksum_advanced_param

New advanced decompression param to ignore checksums
This commit is contained in:
Yann Collet
2020-08-25 12:08:53 -07:00
committed by GitHub
7 changed files with 110 additions and 13 deletions
+27 -11
View File
@@ -114,6 +114,8 @@ static void ZSTD_initDCtx_internal(ZSTD_DCtx* dctx)
dctx->oversizedDuration = 0;
dctx->bmi2 = ZSTD_cpuid_bmi2(ZSTD_cpuid());
dctx->outBufferMode = ZSTD_obm_buffered;
dctx->forceIgnoreChecksum = ZSTD_d_validateChecksum;
dctx->validateChecksum = 1;
#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
dctx->dictContentEndForFuzzing = NULL;
#endif
@@ -446,7 +448,8 @@ static size_t ZSTD_decodeFrameHeader(ZSTD_DCtx* dctx, const void* src, size_t he
RETURN_ERROR_IF(dctx->fParams.dictID && (dctx->dictID != dctx->fParams.dictID),
dictionary_wrong, "");
#endif
if (dctx->fParams.checksumFlag) XXH64_reset(&dctx->xxhState, 0);
dctx->validateChecksum = (dctx->fParams.checksumFlag && !dctx->forceIgnoreChecksum) ? 1 : 0;
if (dctx->validateChecksum) XXH64_reset(&dctx->xxhState, 0);
return 0;
}
@@ -661,7 +664,7 @@ static size_t ZSTD_decompressFrame(ZSTD_DCtx* dctx,
}
if (ZSTD_isError(decodedSize)) return decodedSize;
if (dctx->fParams.checksumFlag)
if (dctx->validateChecksum)
XXH64_update(&dctx->xxhState, op, decodedSize);
if (decodedSize != 0)
op += decodedSize;
@@ -676,11 +679,13 @@ static size_t ZSTD_decompressFrame(ZSTD_DCtx* dctx,
corruption_detected, "");
}
if (dctx->fParams.checksumFlag) { /* Frame content checksum verification */
U32 const checkCalc = (U32)XXH64_digest(&dctx->xxhState);
U32 checkRead;
RETURN_ERROR_IF(remainingSrcSize<4, checksum_wrong, "");
checkRead = MEM_readLE32(ip);
RETURN_ERROR_IF(checkRead != checkCalc, checksum_wrong, "");
if (!dctx->forceIgnoreChecksum) {
U32 const checkCalc = (U32)XXH64_digest(&dctx->xxhState);
U32 checkRead;
checkRead = MEM_readLE32(ip);
RETURN_ERROR_IF(checkRead != checkCalc, checksum_wrong, "");
}
ip += 4;
remainingSrcSize -= 4;
}
@@ -977,7 +982,7 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, c
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);
if (dctx->validateChecksum) XXH64_update(&dctx->xxhState, dst, rSize);
dctx->previousDstEnd = (char*)dst + rSize;
/* Stay on the same stage until we are finished streaming the block. */
@@ -1007,10 +1012,13 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, c
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, "ZSTD_decompressContinue: checksum : calculated %08X :: %08X read", (unsigned)h32, (unsigned)check32);
RETURN_ERROR_IF(check32 != h32, checksum_wrong, "");
{
if (dctx->validateChecksum) {
U32 const h32 = (U32)XXH64_digest(&dctx->xxhState);
U32 const check32 = MEM_readLE32(src);
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;
@@ -1420,6 +1428,10 @@ ZSTD_bounds ZSTD_dParam_getBounds(ZSTD_dParameter dParam)
bounds.lowerBound = (int)ZSTD_obm_buffered;
bounds.upperBound = (int)ZSTD_obm_stable;
return bounds;
case ZSTD_d_forceIgnoreChecksum:
bounds.lowerBound = (int)ZSTD_d_validateChecksum;
bounds.upperBound = (int)ZSTD_d_ignoreChecksum;
return bounds;
default:;
}
bounds.error = ERROR(parameter_unsupported);
@@ -1459,6 +1471,10 @@ size_t ZSTD_DCtx_setParameter(ZSTD_DCtx* dctx, ZSTD_dParameter dParam, int value
CHECK_DBOUNDS(ZSTD_d_stableOutBuffer, value);
dctx->outBufferMode = (ZSTD_outBufferMode_e)value;
return 0;
case ZSTD_d_forceIgnoreChecksum:
CHECK_DBOUNDS(ZSTD_d_forceIgnoreChecksum, value);
dctx->forceIgnoreChecksum = (ZSTD_forceIgnoreChecksum_e)value;
return 0;
default:;
}
RETURN_ERROR(parameter_unsupported, "");
@@ -126,6 +126,8 @@ struct ZSTD_DCtx_s
XXH64_state_t xxhState;
size_t headerSize;
ZSTD_format_e format;
ZSTD_forceIgnoreChecksum_e forceIgnoreChecksum; /* User specified: if == 1, will ignore checksums in compressed frame. Default == 0 */
U32 validateChecksum; /* if == 1, will validate checksum. Is == 1 if (fParams.checksumFlag == 1) and (forceIgnoreChecksum == 0). */
const BYTE* litPtr;
ZSTD_customMem customMem;
size_t litSize;