/* * Hardware entropy collector for the KW41Z, using Freescale's TRNG * * Copyright (C) 2006-2015, 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. * */ /* * Reference: "MKW41Z/31Z/21Z Reference Manual", chapter 43 */ #if DEVICE_TRNG #include "fsl_trng.h" #include "trng_api.h" void trng_init(trng_t *obj) { trng_config_t trngConfig; TRNG_GetDefaultConfig(&trngConfig); /* Set sample mode of the TRNG ring oscillator to Von Neumann, for better random data.*/ trngConfig.sampleMode = kTRNG_SampleModeVonNeumann; /* Initialize TRNG */ TRNG_Init(TRNG0, &trngConfig); } void trng_free(trng_t *obj) { TRNG_Deinit(TRNG0); } int trng_get_bytes(trng_t *obj, uint8_t *output, size_t length, size_t *output_length) { status_t result; result = TRNG_GetRandomData(TRNG0, output, length); if (result == kStatus_Success) { *output_length = length; return 0; } else { return -1; } } #endif