@deftypefun {int} {gnutls_x509_ext_import_key_usage} (const gnutls_datum_t * @var{ext}, unsigned int * @var{key_usage})

@var{ext}: the DER encoded extension data

@var{key_usage}: where the key usage bits will be stored

This function will return certificate's key usage, by reading the DER

data of the keyUsage X.509 extension (2.5.29.15). The key usage value will ORed

values of the: @code{GNUTLS_KEY_DIGITAL_SIGNATURE} ,

@code{GNUTLS_KEY_NON_REPUDIATION} , @code{GNUTLS_KEY_KEY_ENCIPHERMENT} ,

@code{GNUTLS_KEY_DATA_ENCIPHERMENT} , @code{GNUTLS_KEY_KEY_AGREEMENT} ,

@code{GNUTLS_KEY_KEY_CERT_SIGN} , @code{GNUTLS_KEY_CRL_SIGN} ,

@code{GNUTLS_KEY_ENCIPHER_ONLY} , @code{GNUTLS_KEY_DECIPHER_ONLY} .

@strong{Returns:} the certificate key usage, or a negative error code in case of

parsing error.  If the certificate does not contain the keyUsage

extension @code{GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE}  will be

returned.

@strong{Since:} 3.3.0

@end deftypefun