deriveSymKey method

@override Future<String> deriveSymKey(String privKeyA, String pubKeyB)

Implementation

@override
Future<String> deriveSymKey(String privKeyA, String pubKeyB) async {
  // final Uint8List zeros = Uint8List(KEY_LENGTH);

  // var R = ed2.ProjectiveGroupElement();
  // var A = ed2.ExtendedGroupElement();
  // A.FromBytes(Uint8List.fromList(hex.decode(privKeyA)));
  // ed2.GeDoubleScalarMultVartime(
  //   R,
  //   Uint8List.fromList(hex.decode(pubKeyB)),
  //   A,
  //   zeros,
  // );

  // Uint8List sharedKey1 = Uint8List(32);
  // R.ToBytes(sharedKey1);

  // final Uint8List sharedKey1 = TweetNaCl.crypto_scalarmult(
  //   zeros,
  //   Uint8List.fromList(hex.decode(privKeyA)),
  //   Uint8List.fromList(hex.decode(pubKeyB)),
  // );

  // print(sharedKey1);

  final Uint8List sharedKey1 = x.X25519(
    hex.decode(privKeyA),
    hex.decode(pubKeyB),
  );

  Uint8List out = Uint8List(KEY_LENGTH);

  final HKDFKeyDerivator hkdf = HKDFKeyDerivator(SHA256Digest());
  final HkdfParameters params = HkdfParameters(
    sharedKey1,
    KEY_LENGTH,
  );
  hkdf.init(params);
  // final pc.KeyParameter keyParam = hkdf.extract(null, sharedKey1);
  hkdf.deriveKey(null, 0, out, 0);
  return hex.encode(out);
}