decryptFileData function

Implementation

String decryptFileData(ByteData data) {
  const passphraseUtf8 = "h0uAdkGReYwu0zuv8eR4AJQNVqCKZxIe";
  const saltPharse = "yIXmS8GVxGbmX2DL";

  if (data.lengthInBytes == 0) {
    throw const ImproperSSLPinningConfig();
  }
  log("read infoencrypted file", name: "com.quixxi.security");
  Uint8List fileContent =
      data.buffer.asUint8List(data.offsetInBytes, data.lengthInBytes);
  String ivHex = '717569787869736869656c6470617373';
  Uint8List salt = convertStringToUint8List(saltPharse);
  Uint8List passphrase = convertStringToUint8List(passphraseUtf8);
  Uint8List key = generateKey(salt, passphrase);
  Uint8List iv = Uint8List.fromList(hex.decode(ivHex));
  String encodedString = utf8.decode(fileContent);
  if (!isBase64(encodedString)) {
    throw const ImproperSSLPinningConfig();
  }
  Uint8List decodedFileContent = base64.decode(encodedString);
  Uint8List decrypted = decrypt(decodedFileContent, key, iv);

  String decryptedString = String.fromCharCodes(decrypted);

  return decryptedString;
}