/* SPDX-License-Identifier: BSD-2-Clause */
/**
* @file
*
* @ingroup RTEMSScoreHash
*
* @brief This header file provides the interfaces of the
* @ref RTEMSScoreHash.
*/
/*
* Copyright (C) 2021 embedded brains GmbH (http://www.embedded-brains.de)
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _RTEMS_SCORE_HASH_H
#define _RTEMS_SCORE_HASH_H
#include <rtems/score/basedefs.h>
#include <sha256.h>
#include <string.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* @defgroup RTEMSScoreHash Hash Handler
*
* @ingroup RTEMSScore
*
* @brief This group contains the Hash Handler implementation.
*
* @{
*/
/**
* @brief This constant represents the size of a hash string.
*
* Accounts for a NUL termination of the hash string.
*/
#define HASH_CONTROL_STRING_SIZE 45
/**
* @brief This type represents a hash value.
*
* The hash value is produced by _Hash_Finalize().
*/
typedef struct {
/**
* @brief This member contains the hash value encoded as a base64url string.
*
* The string is NUL-terminated.
*/
char chars[ HASH_CONTROL_STRING_SIZE ];
} Hash_Control;
/**
* @brief Gets the hash value as a NUL-terminated string.
*
* @param hash is the hash value.
*
* @return Returns the hash value as a NUL-terminated string.
*/
static inline const char *_Hash_Get_string( const Hash_Control *hash )
{
return &hash->chars[ 0 ];
}
/**
* @brief This type represents the context to compute a hash value.
*/
typedef struct {
/**
* @brief This member contains the hash algorithm context.
*/
SHA256_CTX Context;
/**
* @brief This member references a hash value if needed.
*/
Hash_Control *hash;
/**
* @brief This member contains an index into the hash value bytes if needed.
*/
size_t index;
} Hash_Context;
/**
* @brief Initializes the hash context.
*
* @param[out] context is the hash context to initialize.
*/
static inline void _Hash_Initialize( Hash_Context *context )
{
SHA256_Init( &context->Context );
}
/**
* @brief Adds the data to the hash value.
*
* @param[in, out] context is the hash context.
*
* @param begin is the begin address of the data to add.
*
* @param size is the size of the data in bytes.
*/
static inline void _Hash_Add_data(
Hash_Context *context,
const void *begin,
size_t size
)
{
SHA256_Update( &context->Context, begin, size );
}
/**
* @brief Adds the string to the hash value.
*
* @param[in, out] context is the hash context.
*
* @param str is the string to add.
*/
static inline void _Hash_Add_string(
Hash_Context *context,
const char *str
)
{
SHA256_Update( &context->Context, str, strlen( str ) );
}
/**
* @brief Finalizes the hash value computation and produces the hash value.
*
* @param[in, out] context is the hash context.
*
* @param[out] hash is the hash control to store the produced hash value.
*/
void _Hash_Finalize( Hash_Context *context, Hash_Control *hash );
/** @} */
#ifdef __cplusplus
}
#endif
#endif /* _RTEMS_SCORE_HASH_H */
