4 * \brief HAVEGE: HArdware Volatile Entropy Gathering and Expansion
7 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
8 * SPDX-License-Identifier: Apache-2.0
10 * Licensed under the Apache License, Version 2.0 (the "License"); you may
11 * not use this file except in compliance with the License.
12 * You may obtain a copy of the License at
14 * http://www.apache.org/licenses/LICENSE-2.0
16 * Unless required by applicable law or agreed to in writing, software
17 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
18 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
19 * See the License for the specific language governing permissions and
20 * limitations under the License.
22 * This file is part of mbed TLS (https://tls.mbed.org)
24 #ifndef MBEDTLS_HAVEGE_H
25 #define MBEDTLS_HAVEGE_H
27 #if !defined(MBEDTLS_CONFIG_FILE)
30 #include MBEDTLS_CONFIG_FILE
35 #define MBEDTLS_HAVEGE_COLLECT_SIZE 1024
42 * \brief HAVEGE state structure
44 typedef struct mbedtls_havege_state
46 int PT1, PT2, offset[2];
47 int pool[MBEDTLS_HAVEGE_COLLECT_SIZE];
53 * \brief HAVEGE initialization
55 * \param hs HAVEGE state to be initialized
57 void mbedtls_havege_init( mbedtls_havege_state *hs );
60 * \brief Clear HAVEGE state
62 * \param hs HAVEGE state to be cleared
64 void mbedtls_havege_free( mbedtls_havege_state *hs );
67 * \brief HAVEGE rand function
69 * \param p_rng A HAVEGE state
70 * \param output Buffer to fill
71 * \param len Length of buffer
75 int mbedtls_havege_random( void *p_rng, unsigned char *output, size_t len );