gnutls_x509_crt_get_key_purpose_oid3

Arguments

gnutls_x509_crt_t cert

should contain a gnutls_x509_crt_t type

unsigned indx

This specifies which OID to return. Use (0) to get the first one.

void * oid

a pointer to a buffer to hold the OID (may be null)

size_t * oid_size

initially holds the size of oid

unsigned int * critical

output flag to indicate criticality of extension

Overview

This function will extract the key purpose OIDs of the Certificate specified by the given index. These are stored in the Extended Key Usage extension (2.5.29.37) See the GNUTLS_KP_* definitions for human readable names.

If oid is null then only the size will be filled. The oid returned will be null terminated, although oid_size will not account for the trailing null.

Returns

GNUTLS_E_SHORT_MEMORY_BUFFER if the provided buffer is not long enough, and in that case the *oid_size will be updated with the required size. On success 0 is returned.