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gnutls_hkdf_expand(3) — Linux manual page

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

gnutls_hkdf_expand(3)             gnutls            gnutls_hkdf_expand(3)

NAME         top

       gnutls_hkdf_expand - API function

SYNOPSIS         top

       #include <gnutls/crypto.h>

       int gnutls_hkdf_expand(gnutls_mac_algorithm_t mac, const
       gnutls_datum_t * key, const gnutls_datum_t * info, void * output,
       size_t length);

ARGUMENTS         top

       gnutls_mac_algorithm_t mac
                   the mac algorithm used internally

       const gnutls_datum_t * key
                   the pseudorandom key created with HKDF-Extract

       const gnutls_datum_t * info
                   the optional informational data

       void * output
                   the output value of the expand operation

       size_t length
                   the desired length of the output key

DESCRIPTION         top

       This function will derive a variable length keying material from
       the pseudorandom key using the HKDF-Expand function as defined in
       RFC 5869.

RETURNS         top

       Zero or a negative error code on error.

SINCE         top

       3.6.13

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_hkdf_expand(3)

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