Austin Blackstone / Mbed 2 deprecated client-lwip-lightswitch-demo-expanded

mbed client lightswitch demo

Dependencies:   mbed Socket lwip-eth lwip-sys lwip

Fork of mbed-client-classic-example-lwip by Austin Blackstone

mbedtls/source/entropy_hardware_poll.c@11:cada08fc8a70, 2016-06-09 (annotated)

Committer:
mbedAustin
Date:
Thu Jun 09 17:08:36 2016 +0000
Revision:
11:cada08fc8a70
Commit for public Consumption

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mbedAustin 11:cada08fc8a70 1 /*
mbedAustin 11:cada08fc8a70 2 * Temporary "entropy" collector for Cortex-M4
mbedAustin 11:cada08fc8a70 3 *
mbedAustin 11:cada08fc8a70 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
mbedAustin 11:cada08fc8a70 5 * SPDX-License-Identifier: Apache-2.0
mbedAustin 11:cada08fc8a70 6 *
mbedAustin 11:cada08fc8a70 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
mbedAustin 11:cada08fc8a70 8 * not use this file except in compliance with the License.
mbedAustin 11:cada08fc8a70 9 * You may obtain a copy of the License at
mbedAustin 11:cada08fc8a70 10 *
mbedAustin 11:cada08fc8a70 11 * http://www.apache.org/licenses/LICENSE-2.0
mbedAustin 11:cada08fc8a70 12 *
mbedAustin 11:cada08fc8a70 13 * Unless required by applicable law or agreed to in writing, software
mbedAustin 11:cada08fc8a70 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
mbedAustin 11:cada08fc8a70 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
mbedAustin 11:cada08fc8a70 16 * See the License for the specific language governing permissions and
mbedAustin 11:cada08fc8a70 17 * limitations under the License.
mbedAustin 11:cada08fc8a70 18 *
mbedAustin 11:cada08fc8a70 19 * This file is part of mbed TLS (https://tls.mbed.org)
mbedAustin 11:cada08fc8a70 20 */
mbedAustin 11:cada08fc8a70 21
mbedAustin 11:cada08fc8a70 22 /*
mbedAustin 11:cada08fc8a70 23 * WARNING: this is a temporary hack!
mbedAustin 11:cada08fc8a70 24 * 1. Currently does not provide strong entropy, should be replaced to use the
mbedAustin 11:cada08fc8a70 25 * on-board hardware RNG (see IOTSSL-303)
mbedAustin 11:cada08fc8a70 26 * 2. This should be in a separete yotta module which would be a target
mbedAustin 11:cada08fc8a70 27 * dependency of mbedtls (see IOTSSL-313)
mbedAustin 11:cada08fc8a70 28 */
mbedAustin 11:cada08fc8a70 29
mbedAustin 11:cada08fc8a70 30 #if defined(TARGET_LIKE_CORTEX_M4)
mbedAustin 11:cada08fc8a70 31
mbedAustin 11:cada08fc8a70 32 #include "MK64F12.h"
mbedAustin 11:cada08fc8a70 33 #include "core_cm4.h"
mbedAustin 11:cada08fc8a70 34 #include <string.h>
mbedAustin 11:cada08fc8a70 35
mbedAustin 11:cada08fc8a70 36 unsigned long hardclock( void )
mbedAustin 11:cada08fc8a70 37 {
mbedAustin 11:cada08fc8a70 38 static int dwt_started = 0;
mbedAustin 11:cada08fc8a70 39
mbedAustin 11:cada08fc8a70 40 if( dwt_started == 0 )
mbedAustin 11:cada08fc8a70 41 {
mbedAustin 11:cada08fc8a70 42 CoreDebug->DEMCR |= CoreDebug_DEMCR_TRCENA_Msk;
mbedAustin 11:cada08fc8a70 43 DWT->CTRL |= DWT_CTRL_CYCCNTENA_Msk;
mbedAustin 11:cada08fc8a70 44 }
mbedAustin 11:cada08fc8a70 45
mbedAustin 11:cada08fc8a70 46 return( DWT->CYCCNT );
mbedAustin 11:cada08fc8a70 47 }
mbedAustin 11:cada08fc8a70 48
mbedAustin 11:cada08fc8a70 49 int mbedtls_hardware_poll( void *data,
mbedAustin 11:cada08fc8a70 50 unsigned char *output, size_t len, size_t *olen )
mbedAustin 11:cada08fc8a70 51 {
mbedAustin 11:cada08fc8a70 52 unsigned long timer = hardclock();
mbedAustin 11:cada08fc8a70 53 ((void) data);
mbedAustin 11:cada08fc8a70 54 *olen = 0;
mbedAustin 11:cada08fc8a70 55
mbedAustin 11:cada08fc8a70 56 if( len < sizeof(unsigned long) )
mbedAustin 11:cada08fc8a70 57 return( 0 );
mbedAustin 11:cada08fc8a70 58
mbedAustin 11:cada08fc8a70 59 memcpy( output, &timer, sizeof(unsigned long) );
mbedAustin 11:cada08fc8a70 60 *olen = sizeof(unsigned long);
mbedAustin 11:cada08fc8a70 61
mbedAustin 11:cada08fc8a70 62 return( 0 );
mbedAustin 11:cada08fc8a70 63 }
mbedAustin 11:cada08fc8a70 64
mbedAustin 11:cada08fc8a70 65 #endif