Add random generator for stm32L0 + stm32L4

Author: adustm

hal/targets/hal/TARGET_STM/TARGET_STM32L0/entropy_hardware_poll.c

@@ -0,0 +1,83 @@
+/*
+ *  Hardware entropy collector for the STM32L0 family
+ *
+ *  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 (TARGET_STM32L052xx) || defined (TARGET_STM32L053xx) || defined (TARGET_STM32L062xx) ||  defined (TARGET_STM32L063xx) || \
+    defined (TARGET_STM32L072xx) || defined (TARGET_STM32L073xx) || defined (TARGET_STM32L082xx) ||  defined (TARGET_STM32L083xx)
+
+#include <stdlib.h>
+#include "cmsis.h"
+
+/* RNG handler declaration */
+RNG_HandleTypeDef RngHandle;
+
+
+/** rng_get_byte
+ *  @brief Get one byte of entropy from the RNG, assuming it is up and running.
+ *  @param pointer to the hardware generated random byte.
+ */
+static void rng_get_byte( unsigned char *byte )
+{
+    *byte = (unsigned char)HAL_RNG_GetRandomNumber(&RngHandle);
+}
+
+
+/** mbedtls_hardware_poll
+ *  @brief Get len bytes of entropy from the hardware RNG.
+ *  @param data pointer will be NULL
+ *  @param output pointer to the random generated bytes buffer
+ *  @param len input is the requested length of bytes to be generated
+ *  @param olen is the pointer to the length of bytes effectively generated
+ *  @returns 0 if the generation went well. -1 in case of error
+ */
+int mbedtls_hardware_poll( void *data, unsigned char *output, size_t len, size_t *olen )
+{
+    int ret;
+    ((void) data);
+
+    /* RNG Peripheral clock enable */
+    __HAL_RCC_RNG_CLK_ENABLE();
+
+    /* Initialize RNG instance */
+    RngHandle.Instance = RNG;
+    HAL_RNG_Init(&RngHandle);
+
+    /* Get Random byte */
+    for( uint32_t i = 0; i < len; i++ ){
+        rng_get_byte( output + i );
+
+    }
+    *olen = len;
+    /* Just be extra sure that we didn't do it wrong */
+    if( ( __HAL_RNG_GET_FLAG(&RngHandle, (RNG_FLAG_CECS|RNG_FLAG_SECS)) ) != 0 ) {
+        ret = -1;
+    } else {
+        ret = 0;
+    }
+    /*Disable the RNG peripheral */
+    HAL_RNG_DeInit(&RngHandle);
+    /* RNG Peripheral clock disable - assume we're the only users of RNG  */
+    __HAL_RCC_RNG_CLK_DISABLE();
+
+
+    return( ret );
+}
+#endif /* STM32L073RZ */
+

hal/targets/hal/TARGET_STM/TARGET_STM32L4/entropy_hardware_poll.c

@@ -0,0 +1,80 @@
+/*
+ *  Hardware entropy collector for the STM32L4 family
+ *
+ *  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.
+ *
+ */
+
+
+#include <stdlib.h>
+#include "cmsis.h"
+
+/* RNG handler declaration */
+RNG_HandleTypeDef RngHandle;
+
+
+/** rng_get_byte
+ *  @brief Get one byte of entropy from the RNG, assuming it is up and running.
+ *  @param pointer to the hardware generated random byte.
+ */
+static void rng_get_byte( unsigned char *byte )
+{
+    *byte = (unsigned char)HAL_RNG_GetRandomNumber(&RngHandle);
+}
+
+
+/** mbedtls_hardware_poll
+ *  @brief Get len bytes of entropy from the hardware RNG.
+ *  @param data pointer will be NULL
+ *  @param output pointer to the random generated bytes buffer
+ *  @param len input is the requested length of bytes to be generated
+ *  @param olen is the pointer to the length of bytes effectively generated
+ *  @returns 0 if the generation went well. -1 in case of error
+ */
+int mbedtls_hardware_poll( void *data, unsigned char *output, size_t len, size_t *olen )
+{
+    int ret;
+    ((void) data);
+
+    /* RNG Peripheral clock enable */
+    __HAL_RCC_RNG_CLK_ENABLE();
+
+    /* Initialize RNG instance */
+    RngHandle.Instance = RNG;
+    HAL_RNG_Init(&RngHandle);
+
+    /* Get Random byte */
+    for( uint32_t i = 0; i < len; i++ ){
+        rng_get_byte( output + i );
+
+    }
+    *olen = len;
+    /* Just be extra sure that we didn't do it wrong */
+    if( ( __HAL_RNG_GET_FLAG(&RngHandle, (RNG_FLAG_CECS|RNG_FLAG_SECS)) ) != 0 ) {
+        ret = -1;
+    } else {
+        ret = 0;
+    }
+    /*Disable the RNG peripheral */
+    HAL_RNG_DeInit(&RngHandle);
+    /* RNG Peripheral clock disable - assume we're the only users of RNG  */
+    __HAL_RCC_RNG_CLK_DISABLE();
+
+
+    return( ret );
+}
+
+

targets/targets.json

@@ -915,7 +915,7 @@
         "supported_form_factors": ["ARDUINO", "MORPHO"],
         "core": "Cortex-M0+",
         "default_toolchain": "ARM",
-        "extra_labels": ["STM", "STM32L0", "STM32L073RZ"],
+        "extra_labels": ["STM", "STM32L0", "STM32L073RZ", "STM32L073xx"],
         "supported_toolchains": ["ARM", "uARM", "GCC_ARM", "IAR"],
         "inherits": ["Target"],
         "detect_code": ["0760"],