doc/man3/EVP_KEYEXCH_free.pod

   1 =pod
   2
   3 =head1 NAME
   4
   5 EVP_KEYEXCH_fetch, EVP_KEYEXCH_free, EVP_KEYEXCH_up_ref, EVP_KEYEXCH_provider
   6 - Functions to manage EVP_KEYEXCH algorithm objects
   7
   8 =head1 SYNOPSIS
   9
  10  #include <openssl/evp.h>
  11
  12  EVP_KEYEXCH *EVP_KEYEXCH_fetch(OPENSSL_CTX *ctx, const char *algorithm,
  13                                 const char *properties);
  14  void EVP_KEYEXCH_free(EVP_KEYEXCH *exchange);
  15  int EVP_KEYEXCH_up_ref(EVP_KEYEXCH *exchange);
  16  OSSL_PROVIDER *EVP_KEYEXCH_provider(const EVP_KEYEXCH *exchange);
  17
  18 =head1 DESCRIPTION
  19
  20 EVP_KEYEXCH_fetch() fetches the key exchange implementation for the given
  21 B<algorithm> from any provider offering it, within the criteria given
  22 by the B<properties>.
  23 See L<provider(7)/Fetching algorithms> for further information.
  24
  25 The returned value must eventually be freed with EVP_KEYEXCH_free().
  26
  27 EVP_KEYEXCH_free() decrements the reference count for the B<EVP_KEYEXCH>
  28 structure. Typically this structure will have been obtained from an earlier call
  29 to EVP_KEYEXCH_fetch(). If the reference count drops to 0 then the
  30 structure is freed.
  31
  32 EVP_KEYEXCH_up_ref() increments the reference count for an B<EVP_KEYEXCH>
  33 structure.
  34
  35 EVP_KEYEXCH_provider() returns the provider that I<exchange> was fetched from.
  36
  37 =head1 RETURN VALUES
  38
  39 EVP_KEYEXCH_fetch() returns a pointer to a B<EVP_KEYEXCH> for success
  40 or B<NULL> for failure.
  41
  42 EVP_KEYEXCH_up_ref() returns 1 for success or 0 otherwise.
  43
  44 =head1 SEE ALSO
  45
  46 L<provider(7)/Fetching algorithms>, L<OSSL_PROVIDER(3)>
  47
  48 =head1 HISTORY
  49
  50 The functions described here were added in OpenSSL 3.0.
  51
  52 =head1 COPYRIGHT
  53
  54 Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
  55
  56 Licensed under the Apache License 2.0 (the "License").  You may not use
  57 this file except in compliance with the License.  You can obtain a copy
  58 in the file LICENSE in the source distribution or at
  59 L<https://www.openssl.org/source/license.html>.
  60
  61 =cut