1 /** 2 * \file havege.h 3 * 4 * \brief HAVEGE: HArdware Volatile Entropy Gathering and Expansion 5 * 6 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved 7 * SPDX-License-Identifier: Apache-2.0 8 * 9 * Licensed under the Apache License, Version 2.0 (the "License"); you may 10 * not use this file except in compliance with the License. 11 * You may obtain a copy of the License at 12 * 13 * http://www.apache.org/licenses/LICENSE-2.0 14 * 15 * Unless required by applicable law or agreed to in writing, software 16 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 17 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 18 * See the License for the specific language governing permissions and 19 * limitations under the License. 20 * 21 * This file is part of mbed TLS (https://tls.mbed.org) 22 */ 23 #ifndef MBEDTLS_HAVEGE_H 24 #define MBEDTLS_HAVEGE_H 25 26 #include <stddef.h> 27 28 #define MBEDTLS_HAVEGE_COLLECT_SIZE 1024 29 30 #ifdef __cplusplus 31 extern "C" { 32 #endif 33 34 /** 35 * \brief HAVEGE state structure 36 */ 37 typedef struct 38 { 39 int PT1, PT2, offset[2]; 40 int pool[MBEDTLS_HAVEGE_COLLECT_SIZE]; 41 int WALK[8192]; 42 } 43 mbedtls_havege_state; 44 45 /** 46 * \brief HAVEGE initialization 47 * 48 * \param hs HAVEGE state to be initialized 49 */ 50 void mbedtls_havege_init( mbedtls_havege_state *hs ); 51 52 /** 53 * \brief Clear HAVEGE state 54 * 55 * \param hs HAVEGE state to be cleared 56 */ 57 void mbedtls_havege_free( mbedtls_havege_state *hs ); 58 59 /** 60 * \brief HAVEGE rand function 61 * 62 * \param p_rng A HAVEGE state 63 * \param output Buffer to fill 64 * \param len Length of buffer 65 * 66 * \return 0 67 */ 68 int mbedtls_havege_random( void *p_rng, unsigned char *output, size_t len ); 69 70 #ifdef __cplusplus 71 } 72 #endif 73 74 #endif /* havege.h */ 75
