=pod =head1 NAME EVP_PKEY_copy_parameters, EVP_PKEY_missing_parameters, EVP_PKEY_cmp_parameters, EVP_PKEY_cmp - public key parameter and comparison functions =head1 SYNOPSIS #include int EVP_PKEY_missing_parameters(const EVP_PKEY *pkey); int EVP_PKEY_copy_parameters(EVP_PKEY *to, const EVP_PKEY *from); int EVP_PKEY_cmp_parameters(const EVP_PKEY *a, const EVP_PKEY *b); int EVP_PKEY_cmp(const EVP_PKEY *a, const EVP_PKEY *b); =head1 DESCRIPTION The function EVP_PKEY_missing_parameters() returns 1 if the public key parameters of B are missing and 0 if they are present or the algorithm doesn't use parameters. The function EVP_PKEY_copy_parameters() copies the parameters from key B to key B. An error is returned if the parameters are missing in B or present in both B and B and mismatch. If the parameters in B and B are both present and match this function has no effect. The function EVP_PKEY_cmp_parameters() compares the parameters of keys B and B. The function EVP_PKEY_cmp() compares the public key components and parameters (if present) of keys B and B. =head1 NOTES The main purpose of the functions EVP_PKEY_missing_parameters() and EVP_PKEY_copy_parameters() is to handle public keys in certificates where the parameters are sometimes omitted from a public key if they are inherited from the CA that signed it. Since OpenSSL private keys contain public key components too the function EVP_PKEY_cmp() can also be used to determine if a private key matches a public key. =head1 RETURN VALUES The function EVP_PKEY_missing_parameters() returns 1 if the public key parameters of B are missing and 0 if they are present or the algorithm doesn't use parameters. These functions EVP_PKEY_copy_parameters() returns 1 for success and 0 for failure. The function EVP_PKEY_cmp_parameters() and EVP_PKEY_cmp() return 1 if the keys match, 0 if they don't match, -1 if the key types are different and -2 if the operation is not supported. =head1 SEE ALSO L, L =head1 COPYRIGHT Copyright 2006-2016 The OpenSSL Project Authors. All Rights Reserved. Licensed under the OpenSSL license (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 L. =cut