Timothy Beight / Mbed 2 deprecated 6_songs-from-the-cloud

This is a fork due to permission issues

Dependencies:   mbed Socket lwip-eth lwip-sys lwip

Fork of 6_songs-from-the-cloud by MakingMusicWorkshop

mbed-client/mbedtls/source/entropy_hardware_poll.c@0:f7c60d3e7b8a, 2016-05-18 (annotated)

Committer:
maclobdell
Date:
Wed May 18 19:06:32 2016 +0000
Revision:
0:f7c60d3e7b8a
clean version

Who changed what in which revision?

UserRevisionLine numberNew contents of line
maclobdell 0:f7c60d3e7b8a 1 /*
maclobdell 0:f7c60d3e7b8a 2 * Temporary "entropy" collector for Cortex-M4
maclobdell 0:f7c60d3e7b8a 3 *
maclobdell 0:f7c60d3e7b8a 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
maclobdell 0:f7c60d3e7b8a 5 * SPDX-License-Identifier: Apache-2.0
maclobdell 0:f7c60d3e7b8a 6 *
maclobdell 0:f7c60d3e7b8a 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
maclobdell 0:f7c60d3e7b8a 8 * not use this file except in compliance with the License.
maclobdell 0:f7c60d3e7b8a 9 * You may obtain a copy of the License at
maclobdell 0:f7c60d3e7b8a 10 *
maclobdell 0:f7c60d3e7b8a 11 * http://www.apache.org/licenses/LICENSE-2.0
maclobdell 0:f7c60d3e7b8a 12 *
maclobdell 0:f7c60d3e7b8a 13 * Unless required by applicable law or agreed to in writing, software
maclobdell 0:f7c60d3e7b8a 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
maclobdell 0:f7c60d3e7b8a 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
maclobdell 0:f7c60d3e7b8a 16 * See the License for the specific language governing permissions and
maclobdell 0:f7c60d3e7b8a 17 * limitations under the License.
maclobdell 0:f7c60d3e7b8a 18 *
maclobdell 0:f7c60d3e7b8a 19 * This file is part of mbed TLS (https://tls.mbed.org)
maclobdell 0:f7c60d3e7b8a 20 */
maclobdell 0:f7c60d3e7b8a 21
maclobdell 0:f7c60d3e7b8a 22 /*
maclobdell 0:f7c60d3e7b8a 23 * WARNING: this is a temporary hack!
maclobdell 0:f7c60d3e7b8a 24 * 1. Currently does not provide strong entropy, should be replaced to use the
maclobdell 0:f7c60d3e7b8a 25 * on-board hardware RNG (see IOTSSL-303)
maclobdell 0:f7c60d3e7b8a 26 * 2. This should be in a separete yotta module which would be a target
maclobdell 0:f7c60d3e7b8a 27 * dependency of mbedtls (see IOTSSL-313)
maclobdell 0:f7c60d3e7b8a 28 */
maclobdell 0:f7c60d3e7b8a 29
maclobdell 0:f7c60d3e7b8a 30 #if defined(TARGET_LIKE_CORTEX_M4)
maclobdell 0:f7c60d3e7b8a 31
maclobdell 0:f7c60d3e7b8a 32 #include "MK64F12.h"
maclobdell 0:f7c60d3e7b8a 33 #include "core_cm4.h"
maclobdell 0:f7c60d3e7b8a 34 #include <string.h>
maclobdell 0:f7c60d3e7b8a 35
maclobdell 0:f7c60d3e7b8a 36 unsigned long hardclock( void )
maclobdell 0:f7c60d3e7b8a 37 {
maclobdell 0:f7c60d3e7b8a 38 static int dwt_started = 0;
maclobdell 0:f7c60d3e7b8a 39
maclobdell 0:f7c60d3e7b8a 40 if( dwt_started == 0 )
maclobdell 0:f7c60d3e7b8a 41 {
maclobdell 0:f7c60d3e7b8a 42 CoreDebug->DEMCR |= CoreDebug_DEMCR_TRCENA_Msk;
maclobdell 0:f7c60d3e7b8a 43 DWT->CTRL |= DWT_CTRL_CYCCNTENA_Msk;
maclobdell 0:f7c60d3e7b8a 44 }
maclobdell 0:f7c60d3e7b8a 45
maclobdell 0:f7c60d3e7b8a 46 return( DWT->CYCCNT );
maclobdell 0:f7c60d3e7b8a 47 }
maclobdell 0:f7c60d3e7b8a 48
maclobdell 0:f7c60d3e7b8a 49 int mbedtls_hardware_poll( void *data,
maclobdell 0:f7c60d3e7b8a 50 unsigned char *output, size_t len, size_t *olen )
maclobdell 0:f7c60d3e7b8a 51 {
maclobdell 0:f7c60d3e7b8a 52 unsigned long timer = hardclock();
maclobdell 0:f7c60d3e7b8a 53 ((void) data);
maclobdell 0:f7c60d3e7b8a 54 *olen = 0;
maclobdell 0:f7c60d3e7b8a 55
maclobdell 0:f7c60d3e7b8a 56 if( len < sizeof(unsigned long) )
maclobdell 0:f7c60d3e7b8a 57 return( 0 );
maclobdell 0:f7c60d3e7b8a 58
maclobdell 0:f7c60d3e7b8a 59 memcpy( output, &timer, sizeof(unsigned long) );
maclobdell 0:f7c60d3e7b8a 60 *olen = sizeof(unsigned long);
maclobdell 0:f7c60d3e7b8a 61
maclobdell 0:f7c60d3e7b8a 62 return( 0 );
maclobdell 0:f7c60d3e7b8a 63 }
maclobdell 0:f7c60d3e7b8a 64
maclobdell 0:f7c60d3e7b8a 65 #endif