#include <openssl/rand.h> EVP_RAND_CTX *RAND_get0_primary(OSSL_LIB_CTX *ctx); EVP_RAND_CTX *RAND_get0_public(OSSL_LIB_CTX *ctx); EVP_RAND_CTX *RAND_get0_private(OSSL_LIB_CTX *ctx);
The public and private DRBG are thread-local instances, which are used by RAND_bytes() and RAND_priv_bytes(), respectively. The primary DRBG is a global instance, which is not intended to be used directly, but is used internally to reseed the other two instances.
These functions here provide access to the shared DRBG instances.
RAND_get0_public() returns a pointer to the public DRBG instance for the given OSSL_LIB_CTX ctx.
RAND_get0_private() returns a pointer to the private DRBG instance for the given OSSL_LIB_CTX ctx.
In all the above cases the ctx parameter can be NULL in which case the default OSSL_LIB_CTX is used.
For that reason it is recommended not to change the settings of these three instances directly. Instead, an application should change the default settings for new DRBG instances at initialization time, before creating additional threads.
During initialization, it is possible to change the reseed interval and reseed time interval. It is also possible to exchange the reseeding callbacks entirely.
To set the type of DRBG that will be instantiated, use the RAND_set_DRBG_type(3) call before accessing the random number generation infrastructure.
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>.