gnutls_x509_crt_check_hostname2(3) — Linux manual page



NAME         top

       gnutls_x509_crt_check_hostname2 - API function

SYNOPSIS         top

       #include <gnutls/x509.h>

       unsigned gnutls_x509_crt_check_hostname2(gnutls_x509_crt_t cert,
       const char * hostname, unsigned int flags);

ARGUMENTS         top

       gnutls_x509_crt_t cert
                   should contain an gnutls_x509_crt_t type

       const char * hostname
                   A null terminated string that contains a DNS name

       unsigned int flags

DESCRIPTION         top

       This function will check if the given certificate's subject
       matches the given hostname.  This is a basic implementation of
       the matching described in RFC6125, and takes into account
       wildcards, and the DNSName/IPAddress subject alternative name
       PKIX extension.

       IPv4 addresses are accepted by this function in the
       dotted-decimal format (e.g, ddd.ddd.ddd.ddd), and IPv6 addresses
       in the hexadecimal x:x:x:x:x:x:x:x format. For them the IPAddress
       subject alternative name extension is consulted. Previous
       versions to 3.6.0 of GnuTLS in case of a non-match would consult
       (in a non-standard extension) the DNSname and CN fields. This is
       no longer the case.

       When the flag GNUTLS_VERIFY_DO_NOT_ALLOW_WILDCARDS is specified
       no wildcards are considered. Otherwise they are only considered
       if the domain name consists of three components or more, and the
       wildcard starts at the leftmost position.  When the flag
       GNUTLS_VERIFY_DO_NOT_ALLOW_IP_MATCHES is specified, the input
       will be treated as a DNS name, and matching of textual IP
       addresses against the IPAddress part of the alternative name will
       not be allowed.

       The function gnutls_x509_crt_check_ip() is available for matching
       IP addresses.

RETURNS         top

       non-zero for a successful match, and zero on failure.

SINCE         top


REPORTING BUGS         top

       Report bugs to <>.
       Home page:

COPYRIGHT         top

       Copyright © 2001- 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

       This page is part of the GnuTLS (GnuTLS Transport Layer Security
       Library) project.  Information about the project can be found at
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       manual page, send it to  This page was obtained
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gnutls                            3.7.2gnutls_x509_crt_check_hostname2(3)