gnutls_x509_crt_get_subject_alt_name(3) — Linux manual page


gnutls_x509_c...ject_alt_name(3) gnutls gnutls_x509_c...ject_alt_name(3)

NAME         top

       gnutls_x509_crt_get_subject_alt_name - API function

SYNOPSIS         top

       #include <gnutls/x509.h>

       int gnutls_x509_crt_get_subject_alt_name(gnutls_x509_crt_t cert,
       unsigned int seq, void * san, size_t * san_size, unsigned int *

ARGUMENTS         top

       gnutls_x509_crt_t cert
                   should contain a gnutls_x509_crt_t type

       unsigned int seq
                   specifies the sequence number of the alt name (0 for
                   the first one, 1 for the second etc.)

       void * san  is the place where the alternative name will be
                   copied to

       size_t * san_size
                   holds the size of san.

       unsigned int * critical
                   will be non-zero if the extension is marked as
                   critical (may be null)

DESCRIPTION         top

       This function retrieves the Alternative Name (,
       contained in the given certificate in the X509v3 Certificate

       When the SAN type is otherName, it will extract the data in the
       otherName's value field, and GNUTLS_SAN_OTHERNAME is returned.
       You may use gnutls_x509_crt_get_subject_alt_othername_oid() to
       get the corresponding OID and the "virtual" SAN types (e.g.,

       If an otherName OID is known, the data will be decoded.
       Otherwise the returned data will be DER encoded, and you will
       have to decode it yourself.  Currently, only the RFC 3920
       id-on-xmppAddr SAN is recognized.

RETURNS         top

       the alternative subject name type on success, one of the
       enumerated gnutls_x509_subject_alt_name_t.  It will return
       GNUTLS_E_SHORT_MEMORY_BUFFER if  san_size is not large enough to
       hold the value.  In that case  san_size will be updated with the
       required size.  If the certificate does not have an Alternative
       name with the specified sequence number then

REPORTING BUGS         top

       Report bugs to <>.
       Home page:

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

COLOPHON         top

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gnutls                            3.8.2 gnutls_x509_c...ject_alt_name(3)