NAME

       X509_check_private_key, X509_REQ_check_private_key - check the consistency of a private key with the
       public key in an X509 certificate or certificate request

SYNOPSIS

        #include <openssl/x509.h>

        int X509_check_private_key(X509 *x, EVP_PKEY *k);

        int X509_REQ_check_private_key(X509_REQ *x, EVP_PKEY *k);

DESCRIPTION

       X509_check_private_key() function checks the consistency of private key k with the public key in x.

       X509_REQ_check_private_key() is equivalent to X509_check_private_key() except that x represents a
       certificate request of structure X509_REQ.

RETURN VALUES

       X509_check_private_key() and X509_REQ_check_private_key() return 1 if the keys match each other, and 0 if
       not.

       If the key is invalid or an error occurred, the reason code can be obtained using ERR_get_error(3).

BUGS

       The check_private_key functions don't check if k itself is indeed a private key or not. It merely
       compares the public materials (e.g. exponent and modulus of an RSA key) and/or key parameters (e.g. EC
       params of an EC key) of a key pair. So if you pass a public key to these functions in k, it will return
       success.

SEE ALSO

       ERR_get_error(3)

COPYRIGHT

       Copyright 2017-2018 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
       <https://www.openssl.org/source/license.html>.