gnutls_certificate_verify_peers(3) — Linux manual page


gnutls_certi..._verify_peers(3)  gnutls  gnutls_certi..._verify_peers(3)

NAME         top

       gnutls_certificate_verify_peers - API function

SYNOPSIS         top

       #include <gnutls/gnutls.h>

       int gnutls_certificate_verify_peers(gnutls_session_t session,
       gnutls_typed_vdata_st * data, unsigned int elements, unsigned int
       * status);

ARGUMENTS         top

       gnutls_session_t session
                   is a gnutls session

       gnutls_typed_vdata_st * data
                   an array of typed data

       unsigned int elements
                   the number of data elements

       unsigned int * status
                   is the output of the verification

DESCRIPTION         top

       This function will verify the peer's certificate and store the
       the status in the  status variable as a bitwise OR of
       gnutls_certificate_status_t values or zero if the certificate is
       trusted. Note that value in  status is set only when the return
       value of this function is success (i.e, failure to trust a
       certificate does not imply a negative return value).  The default
       verification flags used by this function can be overridden using
       gnutls_certificate_set_verify_flags(). See the documentation of
       gnutls_certificate_verify_peers2() for details in the
       verification process.

       This function will take into account the stapled OCSP responses
       sent by the server, as well as the following X.509 certificate
       extensions: Name Constraints, Key Usage, and Basic Constraints

       The acceptable  data types are GNUTLS_DT_DNS_HOSTNAME,
       two accept as data a null-terminated hostname or email address,
       and the latter a null-terminated object identifier (e.g.,

       If a DNS hostname is provided then this function will compare the
       hostname in the certificate against the given. If names do not
       match the GNUTLS_CERT_UNEXPECTED_OWNER status flag will be set.
       If a key purpose OID is provided and the end-certificate contains
       the extended key usage PKIX extension, it will be required to be
       have the provided key purpose or be marked for any purpose,
       otherwise verification status will have the

       To avoid denial of service attacks some default upper limits
       regarding the certificate key size and chain size are set. To
       override them use gnutls_certificate_set_verify_limits().

       Note that when using raw public-keys verification will not work
       because there is no corresponding certificate body belonging to
       the raw key that can be verified. In that case this function will

RETURNS         top

       GNUTLS_E_SUCCESS (0) when the validation is performed, or a
       negative error code otherwise.  A successful error code means
       that the  status parameter must be checked to obtain the
       validation status.

SINCE         top


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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       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                            3.8.2  gnutls_certi..._verify_peers(3)