fix(mobile): harden address-bar navigation

apps/mobile/src/lib/navigation.test.ts

@@ -0,0 +1,41 @@
+import { describe, expect, it } from 'vitest';
+import { HOME, normalizeUrl } from './navigation';
+
+describe('normalizeUrl', () => {
+  it('returns home for blank input', () => {
+    expect(normalizeUrl('   ')).toBe(HOME);
+  });
+
+  it('keeps valid HTTP(S) URLs', () => {
+    expect(normalizeUrl('https://example.com/path?q=1')).toBe(
+      'https://example.com/path?q=1',
+    );
+    expect(normalizeUrl('http://localhost:3000/health')).toBe(
+      'http://localhost:3000/health',
+    );
+  });
+
+  it('promotes a complete domain to HTTPS', () => {
+    expect(normalizeUrl('docs.example.com/path')).toBe(
+      'https://docs.example.com/path',
+    );
+  });
+
+  it('searches ordinary text', () => {
+    expect(normalizeUrl('privacy first browser')).toBe(
+      'https://duckduckgo.com/?q=privacy%20first%20browser',
+    );
+  });
+
+  it('searches unsupported schemes instead of loading them', () => {
+    expect(normalizeUrl('javascript:alert(1)')).toBe(
+      'https://duckduckgo.com/?q=javascript%3Aalert(1)',
+    );
+  });
+
+  it('does not treat domain-looking text with spaces as a URL', () => {
+    expect(normalizeUrl('example.com malicious suffix')).toBe(
+      'https://duckduckgo.com/?q=example.com%20malicious%20suffix',
+    );
+  });
+});

apps/mobile/src/lib/navigation.ts

@@ -0,0 +1,41 @@
+export const HOME = 'https://tronbrowser.dev';
+
+const DOMAIN_OR_IP =
+  /^(?:(?:[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?\.)+[a-z]{2,63}|(?:\d{1,3}\.){3}\d{1,3}|localhost)(?::\d{1,5})?(?:[/?#][^\s]*)?$/i;
+
+function searchUrl(query: string): string {
+  return `https://duckduckgo.com/?q=${encodeURIComponent(query)}`;
+}
+
+/**
+ * Convert address-bar input into a safe, loadable URL.
+ *
+ * Only explicit HTTP(S) URLs and complete domain/IP inputs are navigated to.
+ * Everything else, including unsupported schemes and domain-looking text with
+ * spaces, becomes a search query instead of reaching the WebView as a URL.
+ */
+export function normalizeUrl(input: string): string {
+  const trimmed = input.trim();
+  if (!trimmed) return HOME;
+
+  if (/^https?:\/\//i.test(trimmed)) {
+    try {
+      const parsed = new URL(trimmed);
+      return parsed.protocol === 'http:' || parsed.protocol === 'https:'
+        ? parsed.toString()
+        : searchUrl(trimmed);
+    } catch {
+      return searchUrl(trimmed);
+    }
+  }
+
+  if (DOMAIN_OR_IP.test(trimmed)) {
+    try {
+      return new URL(`https://${trimmed}`).toString();
+    } catch {
+      return searchUrl(trimmed);
+    }
+  }
+
+  return searchUrl(trimmed);
+}

apps/mobile/src/screens/BrowserScreen.tsx

@@ -9,6 +9,7 @@ import {
   View,
 } from 'react-native';
 import { WebView } from 'react-native-webview';
+import { HOME, normalizeUrl } from '../lib/navigation';
 import { theme } from '../theme';
 
 /**
@@ -19,17 +20,6 @@ import { theme } from '../theme';
  * Ungoogled Chromium engine (see docs/mobile-architecture.md — the engine ships
  * via the native Android build and the Linux-phone desktop build, not Expo).
  */
-const HOME = 'https://tronbrowser.dev';
-
-function normalizeUrl(input: string): string {
-  const trimmed = input.trim();
-  if (!trimmed) return HOME;
-  if (/^https?:\/\//i.test(trimmed)) return trimmed;
-  // A bare domain-looking string → https; otherwise treat as a search query.
-  if (/^[\w-]+(\.[\w-]+)+/.test(trimmed)) return `https://${trimmed}`;
-  return `https://duckduckgo.com/?q=${encodeURIComponent(trimmed)}`;
-}
-
 export function BrowserScreen() {
   const webRef = useRef<WebView>(null);
   const [address, setAddress] = useState(HOME);