gnutls_privkey_sign_hash(3)

NAME
gnutls_privkey_sign_hash - API function

SYNOPSIS
#include <gnutls/abstract.h>

int gnutls_privkey_sign_hash(gnutls_privkey_t signer, gnutls_digest_algorithm_t hash_algo, unsigned int flags, const gnutls_datum_t * hash_data, gnutls_datum_t * signature);

ARGUMENTS

gnutls_privkey_t signer
    Holds the signer's key

gnutls_digest_algorithm_t hash_algo
    The hash algorithm used

unsigned int flags
    Zero or one of gnutls_privkey_flags_t

const gnutls_datum_t * hash_data
    holds the data to be signed

gnutls_datum_t * signature
    will contain newly allocated signature

DESCRIPTION
This function will sign the given hashed data using a signature algorithm supported by the private key. Signature algorithms are always used together with a hash functions. Different hash functions may be used for the RSA algorithm, but only SHA-XXX for the DSA keys.

You may use gnutls_pubkey_get_preferred_hash_algorithm() to determine the hash algorithm.

The flags may be GNUTLS_PRIVKEY_SIGN_FLAG_TLS1_RSA or GNUTLS_PRIVKEY_SIGN_FLAG_RSA_PSS. In the former case this function will ignore hash_algo and perform a raw PKCS1 signature, and in the latter an RSA-PSS signature will be generated.

Note that, not all algorithm support signing already hashed data. When signing with Ed25519, gnutls_privkey_sign_data() should be used.

RETURNS
On success, GNUTLS_E_SUCCESS (0) is returned, otherwise a negative error value.

SINCE
2.12.0

REPORTING BUGS
Report bugs to <bugs@gnutls.org>.
Home page: https://www.gnutls.org

COPYRIGHT
Copyright © 2001-2023 Free Software Foundation, Inc., and others.
Copying and distribution of this file, with or without modification, are permitted in any medium without royalty provided the copyright notice and this notice are preserved.

SEE ALSO
The full documentation for gnutls is maintained as a Texinfo manual. If the /usr/share/doc/gnutls/ directory does not contain the HTML form visit

https://www.gnutls.org/manual/