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gnutls_x509_crt_get_authority_key_id(3) gnutls gnutls_x509_crt_get_authority_key_id(3)


gnutls_x509_crt_get_authority_key_id - API function


#include <gnutls/x509.h>

int gnutls_x509_crt_get_authority_key_id(gnutls_x509_crt_t cert, void * id, size_t * id_size, unsigned int * critical);


gnutls_x509_crt_t cert
should contain a gnutls_x509_crt_t type
void * id
The place where the identifier will be copied
size_t * id_size
Holds the size of the id field.
unsigned int * critical
will be non-zero if the extension is marked as critical (may be null)


This function will return the X.509v3 certificate authority's key identifier. This is obtained by the X.509 Authority Key identifier extension field ( Note that this function only returns the keyIdentifier field of the extension and GNUTLS_E_X509_UNSUPPORTED_EXTENSION, if the extension contains the name and serial number of the certificate. In that case gnutls_x509_crt_get_authority_key_gn_serial() may be used.


On success, GNUTLS_E_SUCCESS (0) is returned, GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE if the extension is not present, otherwise a negative error value.


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