x448_dart

X448 (RFC 7748) Elliptic-Curve Diffie–Hellman for Dart & Flutter.
Secure key generation, public key derivation, and shared secret computation, with FlutterFlow-friendly base64 helpers.

Status: ✅ Pure Dart backend implemented, RFC 7748-compliant, with full test coverage.

Features

• Pure Dart X448 ECDH — no native dependencies, works everywhere Dart runs
• RFC 7748 §5.2 test vectors included
• HKDF-SHA512 helpers for key derivation (binary + base64)
• Works with Flutter, FlutterFlow, and Dart CLI

Example

import 'dart:convert';
import 'package:x448_dart/x448.dart';

Future<void> main() async {
  // Generate key pairs for Alice and Bob
  final alice = await X448.generate();
  final bob   = await X448.generate();

  // Each derives the same shared secret
  final s1 = X448.sharedSecret(
    privateKey: alice.privateKey,
    peerPublicKey: bob.publicKey,
  );
  final s2 = X448.sharedSecret(
    privateKey: bob.privateKey,
    peerPublicKey: alice.publicKey,
  );

  print('Equal? ${base64Encode(s1) == base64Encode(s2)}'); // true
}