encrypt method
Process a single EC point
using the basic ElGamal algorithm.
Implementation
@override
ECPair encrypt(ECPoint point) {
if (_key == null) {
throw StateError('ECElGamalEncryptor is not initialised');
}
var key = _key!;
var ec = key.parameters!;
var k = _generateK(ec.n, _random);
return ECPair(
(ec.G * k)!,
((key.Q! * k)! + point)!,
);
}