@deftypefun {int} {gnutls_certificate_verify_peers3} (gnutls_session_t @var{session}, const char * @var{hostname}, unsigned int * @var{status})
@var{session}: is a gnutls session

@var{hostname}: is the expected name of the peer; may be @code{NULL} 

@var{status}: is the output of the verification

This function will verify the peer's certificate and store the
the status in the  @code{status} variable as a bitwise OR of gnutls_certificate_status_t
values or zero if the certificate is trusted. Note that value in  @code{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 @code{gnutls_certificate_set_verify_flags()} . See the documentation
of @code{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 (pathlen).

If the  @code{hostname} provided is non-NULL then this function will compare
the hostname in the certificate against it. The comparison will follow
the RFC6125 recommendations. If names do not match the
@code{GNUTLS_CERT_UNEXPECTED_OWNER}  status flag will be set.

In order to verify the purpose of the end-certificate (by checking the extended
key usage), use @code{gnutls_certificate_verify_peers()} .

To avoid denial of service attacks some
default upper limits regarding the certificate key size and chain
size are set. To override them use @code{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 return @code{GNUTLS_E_INVALID_REQUEST} .

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

@strong{Since:} 3.1.4
@end deftypefun