aesGcmDecrypt function

Implementation

Uint8List? aesGcmDecrypt(Uint8List key, Uint8List input) {
  if (key.length != _aesKeySize || input.length < _nonceSize + 16) {
    return null;
  }

  final nonce = input.sublist(0, _nonceSize);
  final encrypted = input.sublist(_nonceSize);
  final cipher = GCMBlockCipher(AESEngine())
    ..init(
      false,
      AEADParameters(KeyParameter(key), _macBits, nonce, Uint8List(0)),
    );

  try {
    return cipher.process(encrypted);
  } on InvalidCipherTextException {
    return null;
  } on StateError {
    return null;
  }
}