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Diffstat (limited to 'src/liblzma/check/check.h')
-rw-r--r-- | src/liblzma/check/check.h | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/src/liblzma/check/check.h b/src/liblzma/check/check.h new file mode 100644 index 0000000..3007d88 --- /dev/null +++ b/src/liblzma/check/check.h @@ -0,0 +1,172 @@ +/////////////////////////////////////////////////////////////////////////////// +// +/// \file check.h +/// \brief Internal API to different integrity check functions +// +// Author: Lasse Collin +// +// This file has been put into the public domain. +// You can do whatever you want with this file. +// +/////////////////////////////////////////////////////////////////////////////// + +#ifndef LZMA_CHECK_H +#define LZMA_CHECK_H + +#include "common.h" + +// If the function for external SHA-256 is missing, use the internal SHA-256 +// code. Due to how configure works, these defines can only get defined when +// both a usable header and a type have already been found. +#if !(defined(HAVE_CC_SHA256_INIT) \ + || defined(HAVE_SHA256_INIT) \ + || defined(HAVE_SHA256INIT)) +# define HAVE_INTERNAL_SHA256 1 +#endif + +#if defined(HAVE_INTERNAL_SHA256) +// Nothing +#elif defined(HAVE_COMMONCRYPTO_COMMONDIGEST_H) +# include <CommonCrypto/CommonDigest.h> +#elif defined(HAVE_SHA256_H) +# include <sys/types.h> +# include <sha256.h> +#elif defined(HAVE_SHA2_H) +# include <sys/types.h> +# include <sha2.h> +#endif + +#if defined(HAVE_INTERNAL_SHA256) +/// State for the internal SHA-256 implementation +typedef struct { + /// Internal state + uint32_t state[8]; + + /// Size of the message excluding padding + uint64_t size; +} lzma_sha256_state; +#elif defined(HAVE_CC_SHA256_CTX) +typedef CC_SHA256_CTX lzma_sha256_state; +#elif defined(HAVE_SHA256_CTX) +typedef SHA256_CTX lzma_sha256_state; +#elif defined(HAVE_SHA2_CTX) +typedef SHA2_CTX lzma_sha256_state; +#endif + +#if defined(HAVE_INTERNAL_SHA256) +// Nothing +#elif defined(HAVE_CC_SHA256_INIT) +# define LZMA_SHA256FUNC(x) CC_SHA256_ ## x +#elif defined(HAVE_SHA256_INIT) +# define LZMA_SHA256FUNC(x) SHA256_ ## x +#elif defined(HAVE_SHA256INIT) +# define LZMA_SHA256FUNC(x) SHA256 ## x +#endif + +// Index hashing needs the best possible hash function (preferably +// a cryptographic hash) for maximum reliability. +#if defined(HAVE_CHECK_SHA256) +# define LZMA_CHECK_BEST LZMA_CHECK_SHA256 +#elif defined(HAVE_CHECK_CRC64) +# define LZMA_CHECK_BEST LZMA_CHECK_CRC64 +#else +# define LZMA_CHECK_BEST LZMA_CHECK_CRC32 +#endif + + +/// \brief Structure to hold internal state of the check being calculated +/// +/// \note This is not in the public API because this structure may +/// change in future if new integrity check algorithms are added. +typedef struct { + /// Buffer to hold the final result and a temporary buffer for SHA256. + union { + uint8_t u8[64]; + uint32_t u32[16]; + uint64_t u64[8]; + } buffer; + + /// Check-specific data + union { + uint32_t crc32; + uint64_t crc64; + lzma_sha256_state sha256; + } state; + +} lzma_check_state; + + +/// lzma_crc32_table[0] is needed by LZ encoder so we need to keep +/// the array two-dimensional. +#ifdef HAVE_SMALL +extern uint32_t lzma_crc32_table[1][256]; +extern void lzma_crc32_init(void); +#else +extern const uint32_t lzma_crc32_table[8][256]; +extern const uint64_t lzma_crc64_table[4][256]; +#endif + + +/// \brief Initialize *check depending on type +/// +/// \return LZMA_OK on success. LZMA_UNSUPPORTED_CHECK if the type is not +/// supported by the current version or build of liblzma. +/// LZMA_PROG_ERROR if type > LZMA_CHECK_ID_MAX. +extern void lzma_check_init(lzma_check_state *check, lzma_check type); + +/// Update the check state +extern void lzma_check_update(lzma_check_state *check, lzma_check type, + const uint8_t *buf, size_t size); + +/// Finish the check calculation and store the result to check->buffer.u8. +extern void lzma_check_finish(lzma_check_state *check, lzma_check type); + + +#ifndef LZMA_SHA256FUNC + +/// Prepare SHA-256 state for new input. +extern void lzma_sha256_init(lzma_check_state *check); + +/// Update the SHA-256 hash state +extern void lzma_sha256_update( + const uint8_t *buf, size_t size, lzma_check_state *check); + +/// Finish the SHA-256 calculation and store the result to check->buffer.u8. +extern void lzma_sha256_finish(lzma_check_state *check); + + +#else + +static inline void +lzma_sha256_init(lzma_check_state *check) +{ + LZMA_SHA256FUNC(Init)(&check->state.sha256); +} + + +static inline void +lzma_sha256_update(const uint8_t *buf, size_t size, lzma_check_state *check) +{ +#if defined(HAVE_CC_SHA256_INIT) && SIZE_MAX > UINT32_MAX + // Darwin's CC_SHA256_Update takes uint32_t as the buffer size, + // so use a loop to support size_t. + while (size > UINT32_MAX) { + LZMA_SHA256FUNC(Update)(&check->state.sha256, buf, UINT32_MAX); + buf += UINT32_MAX; + size -= UINT32_MAX; + } +#endif + + LZMA_SHA256FUNC(Update)(&check->state.sha256, buf, size); +} + + +static inline void +lzma_sha256_finish(lzma_check_state *check) +{ + LZMA_SHA256FUNC(Final)(check->buffer.u8, &check->state.sha256); +} + +#endif + +#endif |