mbed-os/connectivity/mbedtls/platform/inc/shared_rng.h

94 lines
2.4 KiB
C

/*
* shared_rng.h
*
* Copyright (C) 2019-2020, Arm Limited, All Rights Reserved
* 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 SHARED_RNG_H
#define SHARED_RNG_H
#if !defined(MBEDTLS_CONFIG_FILE)
#include "config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
#if defined(MBEDTLS_SSL_CONF_RNG)
#define MBED_SHARED_RNG_NOT_INITIALIZED -1 /**< init_global_rng not called before global_rng */
#ifdef __cplusplus
extern "C" {
#endif
#include "mbedtls/hmac_drbg.h"
#include "mbedtls/entropy.h"
/**
* \brief Initializes hmac ready for rng
*
* \return 0 if successful, or
* MBEDTLS_ERR_MD_BAD_INPUT_DATA, or
* MBEDTLS_ERR_MD_ALLOC_FAILED, or
* MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED.
*/
int init_global_rng();
/**
* \brief Global HMAC_DRBG generate random
*
* \note Automatically reseeds if reseed_counter is reached or PR is enabled.
* \note init_global_rng function must be called
* before calling this function!
*
* \param ctx DRBG context
* \param dst Buffer to fill
* \param len Length of the buffer
*
* \return 0 if successful, or
* MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED, or
* MBEDTLS_ERR_HMAC_DRBG_REQUEST_TOO_BIG or
* MBED_SHARED_RNG_NOT_INITIALIZED
*/
int global_rng( void *ctx, unsigned char *dst, size_t len );
/**
* \brief Free allocated resources
*/
void free_global_rng();
/**
* \brief Getter function for global hmac context
*
* \return global hmac context
*/
mbedtls_hmac_drbg_context *get_global_hmac_drbg();
/**
* \brief Getter function for global entropy context
*
* \return global entropy context
*/
mbedtls_entropy_context *get_global_entropy();
#ifdef __cplusplus
}
#endif
#endif // MBEDTLS_SSL_CONF_RNG
#endif // SHARED_RNG_H