/**
* \file md.h
*
* \brief This file contains the generic message-digest wrapper.
*
* \author Adriaan de Jong <dejong@fox-it.com>
*/
/*
* Copyright The Mbed TLS Contributors
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef MBEDTLS_MD_H
#define MBEDTLS_MD_H
#include <stddef.h>
#if !defined(MBEDTLS_CONFIG_FILE)
#include "mbedtls/config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
/**
* \addtogroup mbedtls
* \{
* \defgroup mbedtls_md_module Message Digest (MD)
* \{
*/
#define MBEDTLS_ERR_MD_FEATURE_UNAVAILABLE -0x5080 /**< The selected feature is not available. */
#define MBEDTLS_ERR_MD_BAD_INPUT_DATA -0x5100 /**< Bad input parameters to function. */
#define MBEDTLS_ERR_MD_ALLOC_FAILED -0x5180 /**< Failed to allocate memory. */
#define MBEDTLS_ERR_MD_FILE_IO_ERROR -0x5200 /**< Opening or reading of file failed. */
/* MBEDTLS_ERR_MD_HW_ACCEL_FAILED is deprecated and should not be used. */
#define MBEDTLS_ERR_MD_HW_ACCEL_FAILED -0x5280 /**< MD hardware accelerator failed. */
#ifdef __cplusplus
extern "C" {
#endif
/**
* \brief Supported message digests.
*
* \warning MD2, MD4, MD5 and SHA-1 are considered weak message digests and
* their use constitutes a security risk. We recommend considering
* stronger message digests instead.
*
*/
typedef enum {
MBEDTLS_MD_NONE=0, /**< None. */
MBEDTLS_MD_MD2, /**< The MD2 message digest. */
MBEDTLS_MD_MD4, /**< The MD4 message digest. */
MBEDTLS_MD_MD5, /**< The MD5 message digest. */
MBEDTLS_MD_SHA1, /**< The SHA-1 message digest. */
MBEDTLS_MD_SHA224, /**< The SHA-224 message digest. */
MBEDTLS_MD_SHA256, /**< The SHA-256 message digest. */
MBEDTLS_MD_SHA384, /**< The SHA-384 message digest. */
MBEDTLS_MD_SHA512, /**< The SHA-512 message digest. */
MBEDTLS_MD_RIPEMD160, /**< The RIPEMD-160 message digest. */
} mbedtls_md_type_t;
#if defined(MBEDTLS_SHA512_C)
#define MBEDTLS_MD_MAX_SIZE 64 /* longest known is SHA512 */
#else
#define MBEDTLS_MD_MAX_SIZE 32 /* longest known is SHA256 or less */
#endif
#if defined(MBEDTLS_SHA512_C)
#define MBEDTLS_MD_MAX_BLOCK_SIZE 128
#else
#define MBEDTLS_MD_MAX_BLOCK_SIZE 64
#endif
/**
* Opaque struct defined in md_internal.h.
*/
typedef struct mbedtls_md_info_t mbedtls_md_info_t;
/**
* The generic message-digest context.
*/
typedef struct mbedtls_md_context_t
{
/** Information about the associated message digest. */
const mbedtls_md_info_t *md_info;
/** The digest-specific context. */
void *md_ctx;
/** The HMAC part of the context. */
void *hmac_ctx;
} mbedtls_md_context_t;
/**
* \brief This function returns the list of digests supported by the
* generic digest module.
*
* \note The list starts with the strongest available hashes.
*
* \return A statically allocated array of digests. Each element
* in the returned list is an integer belonging to the
* message-digest enumeration #mbedtls_md_type_t.
* The last entry is 0.
*/
const int *mbedtls_md_list( void );
/**
* \brief This function returns the message-digest information
* associated with the given digest name.
*
* \param md_name The name of the digest to search for.
*
* \return The message-digest information associated with \p md_name.
* \return NULL if the associated message-digest information is not found.
*/
const mbedtls_md_info_t *mbedtls_md_info_from_string( const char *md_name );
/**
* \brief This function returns the message-digest information
* associated with the given digest type.
*
* \param md_type The type of digest to search for.
*
* \return The message-digest information associated with \p md_type.
* \return NULL if the associated message-digest information is not found.
*/
const mbedtls_md_info_t *mbedtls_md_info_from_type( mbedtls_md_type_t md_type );
/**
* \brief This function initializes a message-digest context without
* binding it to a particular message-digest algorithm.
*
* This function should always be called first. It prepares the
* context for mbedtls_md_setup() for binding it to a
* message-digest algorithm.
*/
void mbedtls_md_init( mbedtls_md_context_t *ctx );
/**
* \brief This function clears the internal structure of \p ctx and
* frees any embedded internal structure, but does not free
* \p ctx itself.
*
* If you have called mbedtls_md_setup() on \p ctx, you must
* call mbedtls_md_free() when you are no longer using the
* context.
* Calling this function if you have previously
* called mbedtls_md_init() and nothing else is optional.
* You must not call this function if you have not called
* mbedtls_md_init().
*/
void mbedtls_md_free( mbedtls_md_context_t *ctx );
#if ! defined(MBEDTLS_DEPRECATED_REMOVED)
#if defined(MBEDTLS_DEPRECATED_WARNING)
#define MBEDTLS_DEPRECATED __attribute__((deprecated))
#else
#define MBEDTLS_DEPRECATED
#endif
/**
* \brief This function selects the message digest algorithm to use,
* and allocates internal structures.
*
* It should be called after mbedtls_md_init() or mbedtls_md_free().
* Makes it necessary to call mbedtls_md_free() later.
*
* \deprecated Superseded by mbedtls_md_setup() in 2.0.0
*
* \param ctx The context to set up.
* \param md_info The information structure of the message-digest algorithm
* to use.
*
* \return \c 0 on success.
* \return #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
* failure.
* \return #MBEDTLS_ERR_MD_ALLOC_FAILED on memory-allocation failure.
*/
int mbedtls_md_init_ctx( mbedtls_md_context_t *ctx, const mbedtls_md_info_t *md_info ) MBEDTLS_DEPRECATED;
#undef MBEDTLS_DEPRECATED
#endif /* MBEDTLS_DEPRECATED_REMOVED */
/**
* \brief This function selects the message digest algorithm to use,
* and allocates internal structures.
*
* It should be called after mbedtls_md_init() or
* mbedtls_md_free(). Makes it necessary to call
* mbedtls_md_free() later.
*
* \param ctx The context to set up.
* \param md_info The information structure of the message-digest algorithm
* to use.
* \param hmac Defines if HMAC is used. 0: HMAC is not used (saves some memory),
* or non-zero: HMAC is used with this context.
*
* \return \c 0 on success.
* \return #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
* failure.
* \return #MBEDTLS_ERR_MD_ALLOC_FAILED on memory-allocation failure.
*/
int mbedtls_md_setup( mbedtls_md_context_t *ctx, const mbedtls_md_info_t *md_info, int hmac );
/**
* \brief This function clones the state of an message-digest
* context.
*
* \note You must call mbedtls_md_setup() on \c dst before calling
* this function.
*
* \note The two contexts must have the same type,
* for example, both are SHA-256.
*
* \warning This function clones the message-digest state, not the
* HMAC state.
*
* \param dst The destination context.
* \param src The context to be cloned.
*
* \return \c 0 on success.
* \return #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification failure.
*/
int mbedtls_md_clone( mbedtls_md_context_t *dst,
const mbedtls_md_context_t *src );
/**
* \brief This function extracts the message-digest size from the
* message-digest information structure.
*
* \param md_info The information structure of the message-digest algorithm
* to use.
*
* \return The size of the message-digest output in Bytes.
*/
unsigned char mbedtls_md_get_size( const mbedtls_md_info_t *md_info );
/**
* \brief This function extracts the message-digest type from the
* message-digest information structure.
*
* \param md_info The information structure of the message-digest algorithm
* to use.
*
* \return The type of the message digest.
*/
mbedtls_md_type_t mbedtls_md_get_type( const mbedtls_md_info_t *md_info );
/**
* \brief This function extracts the message-digest name from the
* message-digest information structure.
*
* \param md_info The information structure of the message-digest algorithm
* to use.
*
* \return The name of the message digest.
*/
const char *mbedtls_md_get_name( const mbedtls_md_info_t *md_info );
/**
* \brief This function starts a message-digest computation.
*
* You must call this function after setting up the context
* with mbedtls_md_setup(), and before passing data with
* mbedtls_md_update().
*
* \param ctx The generic message-digest context.
*
* \return \c 0 on success.
* \return #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
* failure.
*/
int mbedtls_md_starts( mbedtls_md_context_t *ctx );
/**
* \brief This function feeds an input buffer into an ongoing
* message-digest computation.
*
* You must call mbedtls_md_starts() before calling this
* function. You may call this function multiple times.
* Afterwards, call mbedtls_md_finish().
*
* \param ctx The generic message-digest context.
* \param input The buffer holding the input data.
* \param ilen The length of the input data.
*
* \return \c 0 on success.
* \return #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
* failure.
*/
int mbedtls_md_update( mbedtls_md_context_t *ctx, const unsigned char *input, size_t ilen );
/**
* \brief This function finishes the digest operation,
* and writes the result to the output buffer.
*
* Call this function after a call to mbedtls_md_starts(),
* followed by any number of calls to mbedtls_md_update().
* Afterwards, you may either clear the context with
* mbedtls_md_free(), or call mbedtls_md_starts() to reuse
* the context for another digest operation with the same
* algorithm.
*
* \param ctx The generic message-digest context.
* \param output The buffer for the generic message-digest checksum result.
*
* \return \c 0 on success.
* \return #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
* failure.
*/
int mbedtls_md_finish( mbedtls_md_context_t *ctx, unsigned char *output );
/**
* \brief This function calculates the message-digest of a buffer,
* with respect to a configurable message-digest algorithm
* in a single call.
*
* The result is calculated as
* Output = message_digest(input buffer).
*
* \param md_info The information structure of the message-digest algorithm
* to use.
* \param input The buffer holding the data.
* \param ilen The length of the input data.
* \param output The generic message-digest checksum result.
*
* \return \c 0 on success.
* \return #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
* failure.
*/
int mbedtls_md( const mbedtls_md_info_t *md_info, const unsigned char *input, size_t ilen,
unsigned char *output );
#if defined(MBEDTLS_FS_IO)
/**
* \brief This function calculates the message-digest checksum
* result of the contents of the provided file.
*
* The result is calculated as
* Output = message_digest(file contents).
*
* \param md_info The information structure of the message-digest algorithm
* to use.
* \param path The input file name.
* \param output The generic message-digest checksum result.
*
* \return \c 0 on success.
* \return #MBEDTLS_ERR_MD_FILE_IO_ERROR on an I/O error accessing
* the file pointed by \p path.
* \return #MBEDTLS_ERR_MD_BAD_INPUT_DATA if \p md_info was NULL.
*/
int mbedtls_md_file( const mbedtls_md_info_t *md_info, const char *path,
unsigned char *output );
#endif /* MBEDTLS_FS_IO */
/**
* \brief This function sets the HMAC key and prepares to
* authenticate a new message.
*
* Call this function after mbedtls_md_setup(), to use
* the MD context for an HMAC calculation, then call
* mbedtls_md_hmac_update() to provide the input data, and
* mbedtls_md_hmac_finish() to get the HMAC value.
*
* \param ctx The message digest context containing an embedded HMAC
* context.
* \param key The HMAC secret key.
* \param keylen The length of the HMAC key in Bytes.
*
* \return \c 0 on success.
* \return #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
* failure.
*/
int mbedtls_md_hmac_starts( mbedtls_md_context_t *ctx, const unsigned char *key,
size_t keylen );
/**
* \brief This function feeds an input buffer into an ongoing HMAC
* computation.
*
* Call mbedtls_md_hmac_starts() or mbedtls_md_hmac_reset()
* before calling this function.
* You may call this function multiple times to pass the
* input piecewise.
* Afterwards, call mbedtls_md_hmac_finish().
*
* \param ctx The message digest context containing an embedded HMAC
* context.
* \param input The buffer holding the input data.
* \param ilen The length of the input data.
*
* \return \c 0 on success.
* \return #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
* failure.
*/
int mbedtls_md_hmac_update( mbedtls_md_context_t *ctx, const unsigned char *input,
size_t ilen );
/**
* \brief This function finishes the HMAC operation, and writes
* the result to the output buffer.
*
* Call this function after mbedtls_md_hmac_starts() and
* mbedtls_md_hmac_update() to get the HMAC value. Afterwards
* you may either call mbedtls_md_free() to clear the context,
* or call mbedtls_md_hmac_reset() to reuse the context with
* the same HMAC key.
*
* \param ctx The message digest context containing an embedded HMAC
* context.
* \param output The generic HMAC checksum result.
*
* \return \c 0 on success.
* \return #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
* failure.
*/
int mbedtls_md_hmac_finish( mbedtls_md_context_t *ctx, unsigned char *output);
/**
* \brief This function prepares to authenticate a new message with
* the same key as the previous HMAC operation.
*
* You may call this function after mbedtls_md_hmac_finish().
* Afterwards call mbedtls_md_hmac_update() to pass the new
* input.
*
* \param ctx The message digest context containing an embedded HMAC
* context.
*
* \return \c 0 on success.
* \return #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
* failure.
*/
int mbedtls_md_hmac_reset( mbedtls_md_context_t *ctx );
/**
* \brief This function calculates the full generic HMAC
* on the input buffer with the provided key.
*
* The function allocates the context, performs the
* calculation, and frees the context.
*
* The HMAC result is calculated as
* output = generic HMAC(hmac key, input buffer).
*
* \param md_info The information structure of the message-digest algorithm
* to use.
* \param key The HMAC secret key.
* \param keylen The length of the HMAC secret key in Bytes.
* \param input The buffer holding the input data.
* \param ilen The length of the input data.
* \param output The generic HMAC result.
*
* \return \c 0 on success.
* \return #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
* failure.
*/
int mbedtls_md_hmac( const mbedtls_md_info_t *md_info, const unsigned char *key, size_t keylen,
const unsigned char *input, size_t ilen,
unsigned char *output );
/* Internal use */
int mbedtls_md_process( mbedtls_md_context_t *ctx, const unsigned char *data );
/// \}
/// \}
#ifdef __cplusplus
}
#endif
#endif /* MBEDTLS_MD_H */
