gnutls_x509_crt_get_basic_constraints — API function


#include <gnutls/x509.h>
int gnutls_x509_crt_get_basic_constraints( gnutls_x509_crt_t cert,
  unsigned int * critical,
  unsigned int * ca,
  int * pathlen);


gnutls_x509_crt_t cert

should contain a gnutls_x509_crt_t structure

unsigned int * critical

will be non−zero if the extension is marked as critical

unsigned int * ca

pointer to output integer indicating CA status, may be NULL, value is 1 if the certificate CA flag is set, 0 otherwise.

int * pathlen

pointer to output integer indicating path length (may be NULL), non−negative error codes indicate a present pathLenConstraint field and the actual value, −1 indicate that the field is absent.


This function will read the certificate's basic constraints, and return the certificates CA status. It reads the basicConstraints X.509 extension (


If the certificate is a CA a positive value will be returned, or (0) if the certificate does not have CA flag set. A negative error code may be returned in case of errors. If the certificate does not contain the basicConstraints extension GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE will be returned.


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