gnutls_x509_crt_get_extension_by_oid — API function


#include <gnutls/x509.h>
int gnutls_x509_crt_get_extension_by_oid( gnutls_x509_crt_t cert,
  const char * oid,
  int indx,
  void * buf,
  size_t * buf_size,
  unsigned int * critical);


gnutls_x509_crt_t cert

should contain a gnutls_x509_crt_t structure

const char * oid

holds an Object Identified in null terminated string

int indx

In case multiple same OIDs exist in the extensions, this specifies which to send. Use (0) to get the first one.

void * buf

a pointer to a structure to hold the name (may be null)

size_t * buf_size

initially holds the size of buf

unsigned int * critical

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


This function will return the extension specified by the OID in the certificate. The extensions will be returned as binary data DER encoded, in the provided buffer.


On success, GNUTLS_E_SUCCESS (0) is returned, otherwise a negative error code is returned. If the certificate does not contain the specified extension GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE will be returned.


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The full documentation for gnutls is maintained as a Texinfo manual. If the info and gnutls programs are properly installed at your site, the command

info gnutls

should give you access to the complete manual. As an alternative you may obtain the manual from:


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