API function


#include <gnutls/x509.h>

void gnutls_session_set_verify_output_function(gnutls_session_t session, gnutls_verify_output_function * func);


gnutls_session_t session

is a gnutls_x509_trust_list_t type.

gnutls_verify_output_function * func

is the callback function


This function sets a callback to be called when the peer's certificate chain has to be verified and full path to the trusted root has to be printed.

The callback's function prototype is defined in `x509.h': int (*callback)( gnutls_x509_crt_t cert, gnutls_x509_crt_t issuer, gnutls_x509_crl_t crl, unsigned int verification_output);

If the callback function is provided then gnutls will call it, in the certificate verification procedure. To verify the certificate chain and print its path uptp the trusted root, functions such as gnutls_certificate_verify_peers(), gnutls_x509_trust_list_verify_crt(), and gnutls_x509_trust_list_verify_crt2() can be used. The callback is set in _gnutls_verify_crt_status() and _gnutls_pkcs11_verify_crt_status().



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3.8.3 gnutls