int gnutls_x509_crt_get_key_id(gnutls_x509_crt_t crt, unsigned int flags, unsigned char * output_data, size_t * output_data_size);
ARGUMENTS
gnutls_x509_crt_t crt
Holds the certificate
unsigned int flags
should be 0 for now
unsigned char * output_data
will contain the key ID
size_t * output_data_size
holds the size of output_data (and will be
replaced by the actual size of parameters)
DESCRIPTION
This function will return a unique ID the depends on the public
key parameters. This ID can be used in checking whether a
certificate corresponds to the given private key.
If the buffer provided is not long enough to hold the output, then
*output_data_size is updated and GNUTLS_E_SHORT_MEMORY_BUFFER will
be returned. The output will normally be a SHA-1 hash output,
which is 20 bytes.
RETURN VALUE
In case of failure a negative value will be
returned, and 0 on success.