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gnutls_x509_ext_import_key_usage(3) — Linux manual page

NAME | SYNOPSIS | ARGUMENTS | DESCRIPTION | RETURNS | SINCE | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON 

gnutls_x509_e...ort_key_usage(3)  gnutls gnutls_x509_e...ort_key_usage(3)

NAME         top

       gnutls_x509_ext_import_key_usage - API function

SYNOPSIS         top

       #include <gnutls/x509-ext.h>

       int gnutls_x509_ext_import_key_usage(const gnutls_datum_t * ext,
       unsigned int * key_usage);

ARGUMENTS         top

       const gnutls_datum_t * ext
                   the DER encoded extension data

       unsigned int * key_usage
                   where the key usage bits will be stored

DESCRIPTION         top

       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: GNUTLS_KEY_DIGITAL_SIGNATURE,
       GNUTLS_KEY_NON_REPUDIATION, GNUTLS_KEY_KEY_ENCIPHERMENT,
       GNUTLS_KEY_DATA_ENCIPHERMENT, GNUTLS_KEY_KEY_AGREEMENT,
       GNUTLS_KEY_KEY_CERT_SIGN, GNUTLS_KEY_CRL_SIGN,
       GNUTLS_KEY_ENCIPHER_ONLY, GNUTLS_KEY_DECIPHER_ONLY.

RETURNS         top

       the certificate key usage, or a negative error code in case of
       parsing error.  If the certificate does not contain the keyUsage
       extension GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE will be returned.

SINCE         top

       3.3.0

REPORTING BUGS         top

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

COPYRIGHT         top

       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         top

       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/

COLOPHON         top

       This page is part of the GnuTLS (GnuTLS Transport Layer Security
       Library) project.  Information about the project can be found at
       ⟨http://www.gnutls.org/⟩.  If you have a bug report for this
       manual page, send it to bugs@gnutls.org.  This page was obtained
       from the tarball fetched from
       ⟨https://www.gnupg.org/ftp/gcrypt/gnutls/⟩ on 2025-08-11.  If you
       discover any rendering problems in this HTML version of the page,
       or you believe there is a better or more up-to-date source for the
       page, or you have corrections or improvements to the information
       in this COLOPHON (which is not part of the original manual page),
       send a mail to man-pages@man7.org

gnutls                            3.8.10 gnutls_x509_e...ort_key_usage(3)

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