dane_verify_crt man page

dane_verify_crt — API function


#include <gnutls/dane.h>

int dane_verify_crt(dane_state_t s, const gnutls_datum_t * chain, unsigned chain_size, gnutls_certificate_type_t chain_type, const char * hostname, const char * proto, unsigned int port, unsigned int sflags, unsigned int vflags, unsigned int * verify);


dane_state_t s

A DANE state structure (may be NULL)

const gnutls_datum_t * chain

A certificate chain

unsigned chain_size

The size of the chain

gnutls_certificate_type_t chain_type

The type of the certificate chain

const char * hostname

The hostname associated with the chain

const char * proto

The protocol of the service connecting (e.g. tcp)

unsigned int port

The port of the service connecting (e.g. 443)

unsigned int sflags

Flags for the initialization of s (if NULL)

unsigned int vflags

Verification flags; an OR'ed list of dane_verify_flags_t.

unsigned int * verify

An OR'ed list of dane_verify_status_t.


This function will verify the given certificate chain against the CA constrains and/or the certificate available via DANE. If no information via DANE can be obtained the flag DANE_VERIFY_NO_DANE_INFO is set. If a DNSSEC signature is not available for the DANE record then the verify flag DANE_VERIFY_NO_DNSSEC_DATA is set.

Due to the many possible options of DANE, there is no single threat model countered. When notifying the user about DANE verification results it may be better to mention: DANE verification did not reject the certificate, rather than mentioning a successful DANE verication.

Note that this function is designed to be run in addition to PKIX - certificate chain - verification. To be run independently the DANE_VFLAG_ONLY_CHECK_EE_USAGE flag should be specified; then the function will check whether the key of the peer matches the key advertized in the DANE entry.


a negative error code on error and DANE_E_SUCCESS (0) when the DANE entries were successfully parsed, irrespective of whether they were verified (see verify for that information). If no usable entries were encountered DANE_E_REQUESTED_DATA_NOT_AVAILABLE will be returned.

Reporting Bugs

Report bugs to <bugs@gnutls.org>.
Home page: http://www.gnutls.org

See Also

The full documentation for gnutls is maintained as a Texinfo manual. If the /usr/share/doc/gnutls/ directory does not contain the HTML form visit



3.5.9 gnutls