OpenSSL

Cryptography and SSL/TLS Toolkit

EVP_KEYEXCH_free

NAME

EVP_KEYEXCH_fetch, EVP_KEYEXCH_free, EVP_KEYEXCH_up_ref, EVP_KEYEXCH_provider - Functions to manage EVP_KEYEXCH algorithm objects

SYNOPSIS

 #include <openssl/evp.h>

 EVP_KEYEXCH *EVP_KEYEXCH_fetch(OPENSSL_CTX *ctx, const char *algorithm,
                                const char *properties);
 void EVP_KEYEXCH_free(EVP_KEYEXCH *exchange);
 int EVP_KEYEXCH_up_ref(EVP_KEYEXCH *exchange);
 OSSL_PROVIDER *EVP_KEYEXCH_provider(const EVP_KEYEXCH *exchange);

DESCRIPTION

EVP_KEYEXCH_fetch() fetches the key exchange implementation for the given algorithm from any provider offering it, within the criteria given by the properties. See "Fetching algorithms" in provider(7) for further information.

The returned value must eventually be freed with EVP_KEYEXCH_free().

EVP_KEYEXCH_free() decrements the reference count for the EVP_KEYEXCH structure. Typically this structure will have been obtained from an earlier call to EVP_KEYEXCH_fetch(). If the reference count drops to 0 then the structure is freed.

EVP_KEYEXCH_up_ref() increments the reference count for an EVP_KEYEXCH structure.

EVP_KEYEXCH_provider() returns the provider that exchange was fetched from.

RETURN VALUES

EVP_KEYEXCH_fetch() returns a pointer to a EVP_KEYEXCH for success or NULL for failure.

EVP_KEYEXCH_up_ref() returns 1 for success or 0 otherwise.

SEE ALSO

"Fetching algorithms" in provider(7), OSSL_PROVIDER(3)

HISTORY

The functions described here were added in OpenSSL 3.0.

Copyright 2019 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.