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gnutls_x509_crt_get_extension_info(3) gnutls gnutls_x509_crt_get_extension_info(3)


gnutls_x509_crt_get_extension_info - API function


#include <gnutls/x509.h>

int gnutls_x509_crt_get_extension_info(gnutls_x509_crt_t cert, unsigned indx, void * oid, size_t * oid_size, unsigned int * critical);


should contain a gnutls_x509_crt_t type
Specifies which extension OID to send. Use (0) to get the first one.
a pointer to a structure to hold the OID
initially holds the maximum size of oid , on return holds actual size of oid .
output variable with critical flag, may be NULL.


This function will return the requested extension OID in the certificate, and the critical flag for it. The extension OID will be stored as a string in the provided buffer. Use gnutls_x509_crt_get_extension() to extract the data.

If the buffer provided is not long enough to hold the output, then
oid_size is updated and GNUTLS_E_SHORT_MEMORY_BUFFER will be returned. The oid returned will be null terminated, although
oid_size will not account for the trailing null (the latter is not true for GnuTLS prior to 3.6.0).


On success, GNUTLS_E_SUCCESS (0) is returned, otherwise a negative error code is returned. If you have reached the last extension available GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE will be returned.


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