decrypt method

Uint8List decrypt({ required Uint8List data, required Uint8List key, Uint8List? iv, BLOCK_CIPHER_MODE mode = BLOCK_CIPHER_MODE.CBC, })

Implementation

Uint8List decrypt({required Uint8List data, required Uint8List key, Uint8List? iv, BLOCK_CIPHER_MODE mode = BLOCK_CIPHER_MODE.CBC}) {
  _log.finest("AESCipher.decrypt; data size: ${data.length}, data: ${data.hex()}");
  _log.sdVerbose("AESCipher.decrypt; data: ${data.hex()}, key size: ${key.length}, key: ${key.hex()}");

  if (key.length != size) {
    _log.error("AESCipher.decrypt; AES${size * 8} key length must be ${size * 8} bits.");
    throw AESCipherError("AESCipher.decrypt; AES${size * 8} key length must be ${size * 8} bits.");
  }

  if (iv != null){
    _log.sdVerbose("AESCipher.decrypt; iv size: ${iv.length}, iv: ${iv.hex()}");
    if (iv.length != AES_BLOCK_SIZE) {
      _log.error("AESCipher.encrypt; iv length is not 128 bits.");
      throw AESCipherError("AESCipher.encrypt; iv length is not 128 bits.");
    }
  }
  else {
    iv = Uint8List(AES_BLOCK_SIZE);
    _log.sdVerbose("AESCipher.decrypt; iv is null");
  }

  var cipher;
  if (mode == BLOCK_CIPHER_MODE.CBC)
    cipher = CBCBlockCipher(_factory())
      ..init(false, ParametersWithIV(KeyParameter(key), iv));
  else
    cipher = ECBBlockCipher(_factory())..init(false, KeyParameter(key));
    return Uint8List.fromList(_processBlocks(cipher:cipher, data:data).toList());
}