flutter_heyteacher_e2ee

A Flutter package for managing End-to-End Encryption (E2EE) workflows, specifically designed for the Flutter HeyTeacher ecosystem. This package handles the generation, storage, and management of cryptographic keys and Additional Authenticated Data (AAD).

Features

  • Key Generation: Generate cryptographically secure secret keys using AES-GCM encryption.
  • JWK Support: Export and import keys using the JSON Web Key (JWK) standard.
  • Secure Storage: Integrated support for persisting keys using flutter_secure_storage.
  • AAD Management: Specific handling for Additional Authenticated Data to ensure integrity.
  • QR Code Utilities: Helpers for managing key exchange or backup via QR codes.

The components in this packages are implemented following Model-View-ViewModel (MVVM) architecture and Singleton pattern.

Getting started

Add the package to your pubspec.yaml:

dependencies:
  flutter_heyteacher_e2ee:

flutter_heyteacher_e2ee use flutter_heyteacher_auth, so read flutter_heyteacher_auth in order to configure authentication.

Usage

Here is a basic example of how to initialize the view model and generate a key.

import 'package:flutter_heyteacher_e2ee/e2ee.dart';
import 'package:flutter_secure_storage/flutter_secure_storage.dart';

void main() async {

  try {
    // generate Master Secret Key
    E2EEViewModel.masterSecretKeyJwk = await E2EEViewModel.generateSecretKeyJwk();

    // set AAD (aka Password)
    await E2EEViewModel.instance(AuthViewModel.instance.uid).setAAD('jd&76h%d');

    // encrypt text in JSON format
    final e2eeValue = await E2EEViewModel.instance(
        _AuthViewModel.instance.uid,
      ).encrypt('Lorem ipsum dolor sit amet, consectetur adipiscing elit.');

    print('Encrypted Text: ${jsonEncode(e2eeValue.toJson())}}');

    // decrypt text
    final decryptedText = await E2EEViewModel.instance(
        _AuthViewModel.instance.uid,
      ).decrypt(e2eeValue);

    print('Encrypted Text: ${decryptedText}');

  } catch (e) {
    print('Error managing keys: $e');
  }
}

A complete app example can be found in example

Libraries

flutter_heyteacher_e2ee