#include <openssl/core_dispatch.h> #include <openssl/core_names.h> /* * None of these are actual functions, but are displayed like this for * the function signatures for functions that are offered as function * pointers in OSSL_DISPATCH arrays. */ /* Context management */ void *OSSL_FUNC_rand_newctx(void *provctx, void *parent, const OSSL_DISPATCH *parent_calls); void OSSL_FUNC_rand_freectx(void *ctx); /* Random number generator functions: NIST */ int OSSL_FUNC_rand_instantiate(void *ctx, unsigned int strength, int prediction_resistance, const unsigned char *pstr, size_t pstr_len, const OSSL_PARAM params[]); int OSSL_FUNC_rand_uninstantiate(void *ctx); int OSSL_FUNC_rand_generate(void *ctx, unsigned char *out, size_t outlen, unsigned int strength, int prediction_resistance, const unsigned char *addin, size_t addin_len); int OSSL_FUNC_rand_reseed(void *ctx, int prediction_resistance, const unsigned char *ent, size_t ent_len, const unsigned char *addin, size_t addin_len); /* Random number generator functions: additional */ size_t OSSL_FUNC_rand_nonce(void *ctx, unsigned char *out, size_t outlen, int strength, size_t min_noncelen, size_t max_noncelen); size_t OSSL_FUNC_rand_get_seed(void *ctx, unsigned char **buffer, int entropy, size_t min_len, size_t max_len, int prediction_resistance, const unsigned char *adin, size_t adin_len); void OSSL_FUNC_rand_clear_seed(void *ctx, unsigned char *buffer, size_t b_len); int OSSL_FUNC_rand_verify_zeroization(void *ctx); /* Context Locking */ int OSSL_FUNC_rand_enable_locking(void *ctx); int OSSL_FUNC_rand_lock(void *ctx); void OSSL_FUNC_rand_unlock(void *ctx); /* RAND parameter descriptors */ const OSSL_PARAM *OSSL_FUNC_rand_gettable_params(void *provctx); const OSSL_PARAM *OSSL_FUNC_rand_gettable_ctx_params(void *ctx, void *provctx); const OSSL_PARAM *OSSL_FUNC_rand_settable_ctx_params(void *ctx, void *provctx); /* RAND parameters */ int OSSL_FUNC_rand_get_params(OSSL_PARAM params[]); int OSSL_FUNC_rand_get_ctx_params(void *ctx, OSSL_PARAM params[]); int OSSL_FUNC_rand_set_ctx_params(void *ctx, const OSSL_PARAM params[]);
The RAND operation enables providers to implement random number generation algorithms and random number sources and make them available to applications via the API function EVP_RAND(3).
OSSL_FUNC_rand_freectx() is passed a pointer to the provider side rand context in the mctx parameter. If it receives NULL as ctx value, it should not do anything other than return. This function should free any resources associated with that context.
OSSL_FUNC_rand_instantiate() is used to instantiate the DRBG ctx at a requested security strength. In addition, prediction_resistance can be requested. Additional input addin of length addin_len bytes can optionally be provided. The parameters specified in params configure the DRBG and these should be processed before instantiation.
OSSL_FUNC_rand_uninstantiate() is used to uninstantiate the DRBG ctx. After being uninstantiated, a DRBG is unable to produce output until it is instantiated anew.
OSSL_FUNC_rand_generate() is used to generate random bytes from the DRBG ctx. It will generate outlen bytes placing them into the buffer pointed to by out. The generated bytes will meet the specified security strength and, if prediction_resistance is true, the bytes will be produced after reseeding from a live entropy source. Additional input addin of length addin_len bytes can optionally be provided.
OSSL_FUNC_rand_get_seed() is used by deterministic generators to obtain their seeding material from their parent. The seed bytes will meet the specified security level of entropy bits and there will be between min_len and max_len inclusive bytes in total. If prediction_resistance is true, the bytes will be produced from a live entropy source. Additional input addin of length addin_len bytes can optionally be provided. A pointer to the seed material is returned in *buffer and this must be freed by a later call to OSSL_FUNC_rand_clear_seed().
OSSL_FUNC_rand_clear_seed() frees a seed buffer of length b_len bytes which was previously allocated by OSSL_FUNC_rand_get_seed().
OSSL_FUNC_rand_verify_zeroization() is used to determine if the internal state of the DRBG is zero. This capability is mandated by NIST as part of the self tests, it is unlikely to be useful in other circumstances.
OSSL_FUNC_rand_enable_locking() allows locking to be turned on for a DRBG and all of its parent DRBGs. From this call onwards, the DRBG can be used in a thread safe manner.
OSSL_FUNC_rand_lock() is used to lock a DRBG. Once locked, exclusive access is guaranteed.
OSSL_FUNC_rand_unlock() is used to unlock a DRBG.
OSSL_FUNC_rand_get_params() gets details of parameter values associated with the provider algorithm and stores them in params.
OSSL_FUNC_rand_set_ctx_params() sets rand parameters associated with the given provider side rand context ctx to params. Any parameter settings are additional to any that were previously set. Passing NULL for params should return true.
OSSL_FUNC_rand_get_ctx_params() gets details of currently set parameter values associated with the given provider side rand context ctx and stores them in params. Passing NULL for params should return true.
OSSL_FUNC_rand_gettable_params(), OSSL_FUNC_rand_gettable_ctx_params(), and OSSL_FUNC_rand_settable_ctx_params() all return constant OSSL_PARAM(3) arrays as descriptors of the parameters that OSSL_FUNC_rand_get_params(), OSSL_FUNC_rand_get_ctx_params(), and OSSL_FUNC_rand_set_ctx_params() can handle, respectively. OSSL_FUNC_rand_gettable_ctx_params() and OSSL_FUNC_rand_settable_ctx_params() will return the parameters associated with the provider side context ctx in its current state if it is not NULL. Otherwise, they return the parameters associated with the provider side algorithm provctx.
Parameters currently recognised by built-in rands are as follows. Not all parameters are relevant to, or are understood by all rands:
For rands that are also deterministic random bit generators (DRBGs), these additional parameters are recognised. Not all parameters are relevant to, or are understood by all DRBG rands:
OSSL_FUNC_rand_gettable_params(), OSSL_FUNC_rand_gettable_ctx_params() and OSSL_FUNC_rand_settable_ctx_params() should return a constant OSSL_PARAM(3) array, or NULL if none is offered.
OSSL_FUNC_rand_nonce() returns the size of the generated nonce, or 0 on error.
OSSL_FUNC_rand_get_seed() returns the size of the generated seed, or 0 on error.
All of the remaining functions should return 1 for success or 0 on error.
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>.