1 /** 2 * \file entropy_poll.h 3 * 4 * \brief Platform-specific and custom entropy polling functions 5 */ 6 /* 7 * Copyright The Mbed TLS Contributors 8 * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later 9 * 10 * This file is provided under the Apache License 2.0, or the 11 * GNU General Public License v2.0 or later. 12 * 13 * ********** 14 * Apache License 2.0: 15 * 16 * Licensed under the Apache License, Version 2.0 (the "License"); you may 17 * not use this file except in compliance with the License. 18 * You may obtain a copy of the License at 19 * 20 * http://www.apache.org/licenses/LICENSE-2.0 21 * 22 * Unless required by applicable law or agreed to in writing, software 23 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 24 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 25 * See the License for the specific language governing permissions and 26 * limitations under the License. 27 * 28 * ********** 29 * 30 * ********** 31 * GNU General Public License v2.0 or later: 32 * 33 * This program is free software; you can redistribute it and/or modify 34 * it under the terms of the GNU General Public License as published by 35 * the Free Software Foundation; either version 2 of the License, or 36 * (at your option) any later version. 37 * 38 * This program is distributed in the hope that it will be useful, 39 * but WITHOUT ANY WARRANTY; without even the implied warranty of 40 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 41 * GNU General Public License for more details. 42 * 43 * You should have received a copy of the GNU General Public License along 44 * with this program; if not, write to the Free Software Foundation, Inc., 45 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. 46 * 47 * ********** 48 */ 49 #ifndef MBEDTLS_ENTROPY_POLL_H 50 #define MBEDTLS_ENTROPY_POLL_H 51 52 #if !defined(MBEDTLS_CONFIG_FILE) 53 #include "config.h" 54 #else 55 #include MBEDTLS_CONFIG_FILE 56 #endif 57 58 #include <stddef.h> 59 60 #ifdef __cplusplus 61 extern "C" { 62 #endif 63 64 /* 65 * Default thresholds for built-in sources, in bytes 66 */ 67 #define MBEDTLS_ENTROPY_MIN_PLATFORM 32 /**< Minimum for platform source */ 68 #define MBEDTLS_ENTROPY_MIN_HAVEGE 32 /**< Minimum for HAVEGE */ 69 #define MBEDTLS_ENTROPY_MIN_HARDCLOCK 4 /**< Minimum for mbedtls_timing_hardclock() */ 70 #if !defined(MBEDTLS_ENTROPY_MIN_HARDWARE) 71 #define MBEDTLS_ENTROPY_MIN_HARDWARE 32 /**< Minimum for the hardware source */ 72 #endif 73 74 /** 75 * \brief Entropy poll callback that provides 0 entropy. 76 */ 77 #if defined(MBEDTLS_TEST_NULL_ENTROPY) 78 int mbedtls_null_entropy_poll( void *data, 79 unsigned char *output, size_t len, size_t *olen ); 80 #endif 81 82 #if !defined(MBEDTLS_NO_PLATFORM_ENTROPY) 83 /** 84 * \brief Platform-specific entropy poll callback 85 */ 86 int mbedtls_platform_entropy_poll( void *data, 87 unsigned char *output, size_t len, size_t *olen ); 88 #endif 89 90 #if defined(MBEDTLS_HAVEGE_C) 91 /** 92 * \brief HAVEGE based entropy poll callback 93 * 94 * Requires an HAVEGE state as its data pointer. 95 */ 96 int mbedtls_havege_poll( void *data, 97 unsigned char *output, size_t len, size_t *olen ); 98 #endif 99 100 #if defined(MBEDTLS_TIMING_C) 101 /** 102 * \brief mbedtls_timing_hardclock-based entropy poll callback 103 */ 104 int mbedtls_hardclock_poll( void *data, 105 unsigned char *output, size_t len, size_t *olen ); 106 #endif 107 108 #if defined(MBEDTLS_ENTROPY_HARDWARE_ALT) 109 /** 110 * \brief Entropy poll callback for a hardware source 111 * 112 * \warning This is not provided by mbed TLS! 113 * See \c MBEDTLS_ENTROPY_HARDWARE_ALT in config.h. 114 * 115 * \note This must accept NULL as its first argument. 116 */ 117 int mbedtls_hardware_poll( void *data, 118 unsigned char *output, size_t len, size_t *olen ); 119 #endif 120 121 #if defined(MBEDTLS_ENTROPY_NV_SEED) 122 /** 123 * \brief Entropy poll callback for a non-volatile seed file 124 * 125 * \note This must accept NULL as its first argument. 126 */ 127 int mbedtls_nv_seed_poll( void *data, 128 unsigned char *output, size_t len, size_t *olen ); 129 #endif 130 131 #ifdef __cplusplus 132 } 133 #endif 134 135 #endif /* entropy_poll.h */ 136