func (prv *PrivateKey) KEK2012256(pub *PublicKey, ukm *big.Int) ([]byte, error) {
key, err := prv.KEK(pub, ukm)
if err != nil {
func (prv *PrivateKey) KEK2012256(pub *PublicKey, ukm *big.Int) ([]byte, error) {
key, err := prv.KEK(pub, ukm)
if err != nil {