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=head1 NAME

EVP_PKEY_digestsign_supports_digest - indicate support for signature digest

=head1 SYNOPSIS

 #include <openssl/evp.h>
 int EVP_PKEY_digestsign_supports_digest(EVP_PKEY *pkey, OSSL_LIB_CTX *libctx,
                                         const char *name, const char *propq);

=head1 DESCRIPTION

The EVP_PKEY_digestsign_supports_digest() function queries whether the message
digest I<name> is supported for public key signature operations associated with
key I<pkey>. The query is done within an optional library context I<libctx> and
with an optional property query I<propq>.

=head1 RETURN VALUES

The EVP_PKEY_digestsign_supports_digest() function returns 1 if the message
digest algorithm identified by I<name> can be used for public key signature
operations associated with key I<pkey> and 0 if it cannot be used. It returns
a negative value for failure.

=head1 SEE ALSO

L<EVP_DigestSignInit_ex(3)>,

=head1 HISTORY

The EVP_PKEY_digestsign_supports_digest() function was added in OpenSSL 3.0.

=head1 COPYRIGHT

Copyright 2021 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
L<https://www.openssl.org/source/license.html>.

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