Modified mbed TLS headers for AES functionality only to reduce build size
Dependents: BLE_Gateway_Linker_fix BLE_Gateway
Fork of mbedtls by
source/entropy_hardware_poll.c
- Committer:
- electronichamsters
- Date:
- 2017-07-10
- Revision:
- 5:f09f5ed830ca
- Parent:
- 1:24750b9ad5ef
File content as of revision 5:f09f5ed830ca:
/* * Temporary "entropy" collector for Cortex-M4 * * 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. * * This file is part of mbed TLS (https://tls.mbed.org) */ /* * WARNING: this is a temporary hack! * 1. Currently does not provide strong entropy, should be replaced to use the * on-board hardware RNG (see IOTSSL-303) * 2. This should be in a separete yotta module which would be a target * dependency of mbedtls (see IOTSSL-313) */ #if defined(TARGET_LIKE_CORTEX_M4) #include "MK64F12.h" #include "core_cm4.h" #include <string.h> unsigned long hardclock( void ) { static int dwt_started = 0; if( dwt_started == 0 ) { CoreDebug->DEMCR |= CoreDebug_DEMCR_TRCENA_Msk; DWT->CTRL |= DWT_CTRL_CYCCNTENA_Msk; } return( DWT->CYCCNT ); } int mbedtls_hardware_poll( void *data, unsigned char *output, size_t len, size_t *olen ) { unsigned long timer = hardclock(); ((void) data); *olen = 0; if( len < sizeof(unsigned long) ) return( 0 ); memcpy( output, &timer, sizeof(unsigned long) ); *olen = sizeof(unsigned long); return( 0 ); } #endif