1 /* 2 * Copyright 2016-2019 The OpenSSL Project Authors. All Rights Reserved. 3 * 4 * Licensed under the OpenSSL license (the "License"). You may not use 5 * this file except in compliance with the License. You can obtain a copy 6 * in the file LICENSE in the source distribution or at 7 * https://www.openssl.org/source/license.html 8 */ 9 10 /* 11 * Licensed under the OpenSSL licenses, (the "License"); 12 * you may not use this file except in compliance with the License. 13 * You may obtain a copy of the License at 14 * https://www.openssl.org/source/license.html 15 * or in the file LICENSE in the source distribution. 16 */ 17 18 #ifndef OSSL_CRYPTO_RAND_H 19 # define OSSL_CRYPTO_RAND_H 20 21 # include <openssl/rand.h> 22 23 /* forward declaration */ 24 typedef struct rand_pool_st RAND_POOL; 25 26 void rand_cleanup_int(void); 27 void rand_drbg_cleanup_int(void); 28 void drbg_delete_thread_state(void); 29 30 /* Hardware-based seeding functions. */ 31 size_t rand_acquire_entropy_from_tsc(RAND_POOL *pool); 32 size_t rand_acquire_entropy_from_cpu(RAND_POOL *pool); 33 34 /* DRBG entropy callbacks. */ 35 size_t rand_drbg_get_entropy(RAND_DRBG *drbg, 36 unsigned char **pout, 37 int entropy, size_t min_len, size_t max_len, 38 int prediction_resistance); 39 void rand_drbg_cleanup_entropy(RAND_DRBG *drbg, 40 unsigned char *out, size_t outlen); 41 size_t rand_drbg_get_nonce(RAND_DRBG *drbg, 42 unsigned char **pout, 43 int entropy, size_t min_len, size_t max_len); 44 void rand_drbg_cleanup_nonce(RAND_DRBG *drbg, 45 unsigned char *out, size_t outlen); 46 47 size_t rand_drbg_get_additional_data(RAND_POOL *pool, unsigned char **pout); 48 49 void rand_drbg_cleanup_additional_data(RAND_POOL *pool, unsigned char *out); 50 51 /* 52 * RAND_POOL functions 53 */ 54 RAND_POOL *rand_pool_new(int entropy_requested, int secure, 55 size_t min_len, size_t max_len); 56 RAND_POOL *rand_pool_attach(const unsigned char *buffer, size_t len, 57 size_t entropy); 58 void rand_pool_free(RAND_POOL *pool); 59 60 const unsigned char *rand_pool_buffer(RAND_POOL *pool); 61 unsigned char *rand_pool_detach(RAND_POOL *pool); 62 void rand_pool_reattach(RAND_POOL *pool, unsigned char *buffer); 63 64 size_t rand_pool_entropy(RAND_POOL *pool); 65 size_t rand_pool_length(RAND_POOL *pool); 66 67 size_t rand_pool_entropy_available(RAND_POOL *pool); 68 size_t rand_pool_entropy_needed(RAND_POOL *pool); 69 /* |entropy_factor| expresses how many bits of data contain 1 bit of entropy */ 70 size_t rand_pool_bytes_needed(RAND_POOL *pool, unsigned int entropy_factor); 71 size_t rand_pool_bytes_remaining(RAND_POOL *pool); 72 73 int rand_pool_add(RAND_POOL *pool, 74 const unsigned char *buffer, size_t len, size_t entropy); 75 unsigned char *rand_pool_add_begin(RAND_POOL *pool, size_t len); 76 int rand_pool_add_end(RAND_POOL *pool, size_t len, size_t entropy); 77 78 79 /* 80 * Add random bytes to the pool to acquire requested amount of entropy 81 * 82 * This function is platform specific and tries to acquire the requested 83 * amount of entropy by polling platform specific entropy sources. 84 * 85 * If the function succeeds in acquiring at least |entropy_requested| bits 86 * of entropy, the total entropy count is returned. If it fails, it returns 87 * an entropy count of 0. 88 */ 89 size_t rand_pool_acquire_entropy(RAND_POOL *pool); 90 91 /* 92 * Add some application specific nonce data 93 * 94 * This function is platform specific and adds some application specific 95 * data to the nonce used for instantiating the drbg. 96 * 97 * This data currently consists of the process and thread id, and a high 98 * resolution timestamp. The data does not include an atomic counter, 99 * because that is added by the calling function rand_drbg_get_nonce(). 100 * 101 * Returns 1 on success and 0 on failure. 102 */ 103 int rand_pool_add_nonce_data(RAND_POOL *pool); 104 105 106 /* 107 * Add some platform specific additional data 108 * 109 * This function is platform specific and adds some random noise to the 110 * additional data used for generating random bytes and for reseeding 111 * the drbg. 112 * 113 * Returns 1 on success and 0 on failure. 114 */ 115 int rand_pool_add_additional_data(RAND_POOL *pool); 116 117 /* 118 * Initialise the random pool reseeding sources. 119 * 120 * Returns 1 on success and 0 on failure. 121 */ 122 int rand_pool_init(void); 123 124 /* 125 * Finalise the random pool reseeding sources. 126 */ 127 void rand_pool_cleanup(void); 128 129 /* 130 * Control the random pool use of open file descriptors. 131 */ 132 void rand_pool_keep_random_devices_open(int keep); 133 134 #endif 135