gnutls_certificate_verify_peers2 man page

gnutls_certificate_verify_peers2 — API function


#include <gnutls/gnutls.h>

int gnutls_certificate_verify_peers2(gnutls_session_t session, unsigned int * status);


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 gnutls_certificate_set_verify_flags().

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 gnutls_certificate_verify_peers3().


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

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See Also

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3.5.9 gnutls