gnutls_certificate_verify_peers3(3) gnutls gnutls_certificate_verify_peers3(3)

gnutls_certificate_verify_peers3 - API function

#include <gnutls/gnutls.h>

int gnutls_certificate_verify_peers3(gnutls_session_t session, const char * hostname, unsigned int * status);

is a gnutls session
is the expected name of the peer; may be NULL
is the output of the verification

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 (pathlen).

If the 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 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 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 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 GNUTLS_E_INVALID_REQUEST.

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.


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