OSSL_PARAM_dup.3ossl - Man Page

OSSL_PARAM array copy functions


 #include <openssl/params.h>

 OSSL_PARAM *OSSL_PARAM_dup(const OSSL_PARAM *params);
 OSSL_PARAM *OSSL_PARAM_merge(const OSSL_PARAM *params, const OSSL_PARAM *params1);
 void OSSL_PARAM_free(OSSL_PARAM *params);


Algorithm parameters can be exported/imported from/to providers using arrays of OSSL_PARAM. The following utility functions allow the parameters to be duplicated and merged with other OSSL_PARAM to assist in this process.

OSSL_PARAM_dup() duplicates the parameter array params. This function does a deep copy of the data.

OSSL_PARAM_merge() merges the parameter arrays params and params1 into a new parameter array. If params and params1 contain values with the same 'key' then the value from params1 will replace the param value. This function does a shallow copy of the parameters. Either params or params1 may be NULL. The behaviour of the merge is unpredictable if params and params1 contain the same key, and there are multiple entries within either array that have the same key.

OSSL_PARAM_free() frees the parameter array params that was created using OSSL_PARAM_dup(), OSSL_PARAM_merge() or OSSL_PARAM_BLD_to_param().

Return Values

The functions OSSL_PARAM_dup() and OSSL_PARAM_merge() return a newly allocated OSSL_PARAM array, or NULL if there was an error. If both parameters are NULL
then NULL is returned.

See Also



The functions were added in OpenSSL 3.0.

Referenced By


The man pages OSSL_PARAM_free.3ossl(3) and OSSL_PARAM_merge.3ossl(3) are aliases of OSSL_PARAM_dup.3ossl(3).

2021-09-09 3.0.0 OpenSSL