encrypt method

@override Future<SecretBox> encrypt(List<int> clearText, { required SecretKey secretKey, List<int>? nonce, List<int> aad = const <int>[], int keyStreamIndex = 0, })

Encrypts a cleartext.

Parameter keyStreamIndex allows you to choose offset in the keystream.

For other arguments, see Cipher.encrypt.

Implementation

@override
Future<SecretBox> encrypt(
  List<int> clearText, {
  required SecretKey secretKey,
  List<int>? nonce,
  List<int> aad = const <int>[],
  int keyStreamIndex = 0,
}) async {
  nonce ??= newNonce();
  final secretKeyData = await secretKey.extract();
  final actualSecretKeyLength = secretKeyData.bytes.length;
  final expectedSecretKeyLength = secretKeyLength;
  if (actualSecretKeyLength != expectedSecretKeyLength) {
    throw ArgumentError.value(
      secretKey,
      'secretKey',
      'Expected $secretKeyLength bytes, got $actualSecretKeyLength bytes',
    );
  }
  final cipherText = _perform(
    clearText,
    secretKeyData: secretKeyData,
    nonce: nonce,
    aad: aad,
    keyStreamIndex: keyStreamIndex,
  );
  final mac = await macAlgorithm.calculateMac(
    cipherText,
    secretKey: secretKey,
    nonce: nonce,
    aad: aad,
  );
  return SecretBox(cipherText, nonce: nonce, mac: mac);
}