Flutter secure file storage #

An implementation for flutter secure file storage. For example keychain has a soft limit of 4kb. Using the file system instead we can store much larger content.

AES/GCM/NoPadding encryption is used to encrypt the data. The keys are generated using Random.secureand stored using the flutter_secure_storage package, the values are encrypted by the pointycastle package or native for Android

Usage #

It's implemented to use the same structure as FlutterSecureStorage and therefore you can switch easily between them. But we also support Uint8List as input/output

import 'package:flutter_secure_file_storage/flutter_secure_file_storage.dart';
import 'package:flutter_secure_storage/flutter_secure_storage.dart';

// Create storage
final storage = FlutterSecureFileStorage(FlutterSecureStorage());

// Read value
final value = await storage.read<String>(key: key);

// Read all values
Map<String, String> allValues = await storage.readAll();

// Delete value
await storage.delete(key: key);

// Delete all
await storage.deleteAll();

// Write value
await storage.write(key: key, value: value);

Configure Android version #

In [project]/android/app/build.gradle set minSdkVersion to >= 18.

android {
    ...

    defaultConfig {
        ...
        minSdkVersion 18
        ...
    }

}