aia_chaser_webview

Safe Android WebView SSL error interception for aia_chaser, eliminating insecure proceed() calls by dynamically resolving SSL_UNTRUSTED via Authority Information Access (AIA) intermediate certificate chasing.

The Danger of handler.proceed()

When an Android WebView navigates to an HTTPS domain with an incomplete certificate chain, Android raises an onReceivedSslError event with SSL_UNTRUSTED.

Many applications naively do:

// ❌ CRITICAL SECURITY VULNERABILITY!
// Bypasses all SSL verification for every certificate error, including spoofing and MitM attacks.
onReceivedSslError: (controller, error) {
  error.proceed(); 
}

This vulnerability leads to immediate security audit failure and Google Play Store rejection.

aia_chaser_webview replaces blind proceed() with cryptographic verification: it intercepts the SSL error, probes and verifies the complete certificate chain through AIA against the Android system trust store, and only calls proceed() if the chain is proven valid.

Installation

Add aia_chaser and aia_chaser_webview to your pubspec.yaml:

dependencies:
  aia_chaser: ^0.1.0
  aia_chaser_webview: ^0.1.0
  webview_flutter: ^4.10.0
  webview_flutter_android: ^4.7.0

Quick Start

1. Initialize AIA Chaser

import 'package:aia_chaser/aia_chaser.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();

  await AiaChaser.initialize(AiaConfig(
    hosts: {
      'portal.example.com': const HostPolicy.chase(),
    },
  ));

  runApp(const MyApp());
}

2. Attach Handler to WebView NavigationDelegate

import 'package:aia_chaser_webview/aia_chaser_webview.dart';
import 'package:webview_flutter/webview_flutter.dart';
import 'package:webview_flutter_android/webview_flutter_android.dart';

final controller = WebViewController();

if (controller.platform is AndroidWebViewController) {
  final androidController = controller.platform as AndroidWebViewController;
  
  // Attach AIA Chaser SSL error handler
  AiaWebViewHandler.install(
    androidController.navigationDelegate as AndroidNavigationDelegate,
    fallbackHandler: (error) {
      // Optional: Handle true untrusted errors (e.g. self-signed, hostname mismatch)
      error.cancel();
    },
  );
}

controller.loadRequest(Uri.parse('https://portal.example.com'));