gnutls_certificate_verify_peers2 − API function


, unsigned int * int
gnutls_certificate_verify_peers2(gnutls_session_t session

gnutls_session_t session
            is a gnutls session

unsigned int * status
            is the output of the verification

This function will verify the peer’s certificate and store
the status in the  status variable as a bitwise or’d
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

This function will take into account the OCSP Certificate
Status TLS extension, as well as the following X.509
certificate extensions: Name Constraints, Key Usage, and
Basic Constraints (pathlen).

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 you must also check the peer’s name in order to
check if the verified certificate belongs to the actual
peer, see gnutls_x509_crt_check_hostname(), or use

a negative error code on error and GNUTLS_E_SUCCESS (0) when
the peer’s certificate was successfully parsed, whether or
not it was verified.

Report bugs to <>.
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