openssl/providers/implementations/include/prov/seeding.h

/*
 * Copyright 2020-2021 The OpenSSL Project Authors. All Rights Reserved.
 *
 * Licensed under the Apache License 2.0 (the "License").  You may not use
 * this file except in compliance with the License.  You can obtain a copy
 * in the file LICENSE in the source distribution or at
 * https://www.openssl.org/source/license.html
 */

#include "prov/provider_ctx.h"
#include "crypto/rand_pool.h"

/* Hardware-based seeding functions. */
size_t ossl_prov_acquire_entropy_from_tsc(RAND_POOL *pool);
size_t ossl_prov_acquire_entropy_from_cpu(RAND_POOL *pool);

/*
 * Add some platform specific additional data
 *
 * This function is platform specific and adds some random noise to the
 * additional data used for generating random bytes and for reseeding
 * the drbg.
 *
 * Returns 1 on success and 0 on failure.
 */
int ossl_rand_pool_add_additional_data(RAND_POOL *pool);

/*
 * External seeding functions from the core dispatch table.
 */
int ossl_prov_seeding_from_dispatch(const OSSL_DISPATCH *fns);

size_t ossl_prov_get_entropy(PROV_CTX *prov_ctx, unsigned char **pout,
                             int entropy, size_t min_len, size_t max_len);
void ossl_prov_cleanup_entropy(PROV_CTX *prov_ctx, unsigned char *buf,
                               size_t len);
size_t ossl_prov_get_nonce(PROV_CTX *prov_ctx, unsigned char **pout,
                           size_t min_len, size_t max_len,
                           const void *salt, size_t salt_len);
void ossl_prov_cleanup_nonce(PROV_CTX *prov_ctx, unsigned char *buf,
                             size_t len);