MBED-DEV only fro Nucleo STM32F303K8T6
Fork of mbed-dev by
targets/TARGET_STM/trng_api.c
- Committer:
- <>
- Date:
- 2016-10-28
- Revision:
- 149:156823d33999
File content as of revision 149:156823d33999:
/* * Hardware entropy collector for the STM32 families * * Copyright (C) 2006-2016, 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. * */ #if defined(DEVICE_TRNG) #include <stdlib.h> #include "cmsis.h" #include "trng_api.h" /** trng_get_byte * @brief Get one byte of entropy from the RNG, assuming it is up and running. * @param obj TRNG obj * @param pointer to the hardware generated random byte. */ static void trng_get_byte(trng_t *obj, unsigned char *byte ) { *byte = (unsigned char)HAL_RNG_GetRandomNumber(&obj->handle); } void trng_init(trng_t *obj) { #if defined(TARGET_STM32L4) RCC_PeriphCLKInitTypeDef PeriphClkInitStruct; /*Select PLLQ output as RNG clock source */ PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_RNG; PeriphClkInitStruct.RngClockSelection = RCC_RNGCLKSOURCE_PLL; HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct); #endif /* RNG Peripheral clock enable */ __HAL_RCC_RNG_CLK_ENABLE(); /* Initialize RNG instance */ obj->handle.Instance = RNG; HAL_RNG_Init(&obj->handle); /* first random number generated after setting the RNGEN bit should not be used */ HAL_RNG_GetRandomNumber(&obj->handle); } void trng_free(trng_t *obj) { /*Disable the RNG peripheral */ HAL_RNG_DeInit(&obj->handle); /* RNG Peripheral clock disable - assume we're the only users of RNG */ __HAL_RCC_RNG_CLK_DISABLE(); } int trng_get_bytes(trng_t *obj, uint8_t *output, size_t length, size_t *output_length) { int ret; /* Get Random byte */ for( uint32_t i = 0; i < length; i++ ){ trng_get_byte(obj, output + i ); } *output_length = length; /* Just be extra sure that we didn't do it wrong */ if( ( __HAL_RNG_GET_FLAG(&obj->handle, (RNG_FLAG_CECS | RNG_FLAG_SECS)) ) != 0 ) { ret = -1; } else { ret = 0; } return( ret ); } #endif