移动壳阻断下载协议导航

补强 WebView 下载脚本和下载协议导航阻断

新增移动壳下载策略行为测试和配置门禁

同步宿主壳方案文档和团队决策记录

apps/mobile-shell/scripts/check-config.mjs

@@ -28,6 +28,8 @@ const hostBridgeSource = bridgeSourceFiles
   .join('\n');
 const urlPath = new URL('../src/shell/url.ts', import.meta.url);
 const urlSource = fs.readFileSync(urlPath, 'utf8');
+const webViewPolicyPath = new URL('../src/shell/webViewPolicy.ts', import.meta.url);
+const webViewPolicySource = fs.readFileSync(webViewPolicyPath, 'utf8');
 const runtimePath = new URL('../src/shell/runtime.ts', import.meta.url);
 const runtimeSource = fs.readFileSync(runtimePath, 'utf8');
 const sharedContractPath = new URL(
@@ -733,6 +735,7 @@ for (const snippet of [
   'origin: window.location.origin',
   'source: window',
   'BLOCK_WEBVIEW_DOWNLOAD_SCRIPT',
+  'shouldBlockMobileWebViewNavigationRequest',
   'SafeAreaProvider',
   'SafeAreaView',
   'MOBILE_SHELL_SAFE_AREA_EDGES',
@@ -749,7 +752,8 @@ for (const snippet of [
   'sharedCookiesEnabled={false}',
   'webviewDebuggingEnabled={false}',
   'injectedJavaScriptBeforeContentLoaded={BLOCK_WEBVIEW_DOWNLOAD_SCRIPT}',
-  'onFileDownload={() => undefined}',
+  'handleBlockedFileDownload',
+  'onFileDownload={handleBlockedFileDownload}',
   'setSupportMultipleWindows={false}',
 ]) {
   if (!shellAppSource.includes(snippet)) {
@@ -757,6 +761,24 @@ for (const snippet of [
   }
 }
 
+for (const snippet of [
+  'MOBILE_WEBVIEW_BLOCKED_DOWNLOAD_PROTOCOLS',
+  "'blob:'",
+  "'data:'",
+  "'file:'",
+  "'filesystem:'",
+  'shouldBlockMobileWebViewDownloadUrl',
+  'shouldBlockMobileWebViewNavigationRequest',
+  "target.closest('a')",
+  'event.stopImmediatePropagation()',
+  'window.open = function(url)',
+  'HTMLAnchorElement.prototype.click',
+]) {
+  if (!webViewPolicySource.includes(snippet)) {
+    throw new Error(`mobile shell WebView policy missing ${snippet}`);
+  }
+}
+
 if (!appSource.includes("import ShellApp from './src/shell/ShellApp';")) {
   throw new Error('mobile shell App must import the shell app facade');
 }

apps/mobile-shell/src/shell/ShellApp.tsx

@@ -34,7 +34,10 @@ import {
   buildMobileShellUrl,
   resolveMobileShellBaseWebUrl,
 } from './url';
-import { BLOCK_WEBVIEW_DOWNLOAD_SCRIPT } from './webViewPolicy';
+import {
+  BLOCK_WEBVIEW_DOWNLOAD_SCRIPT,
+  shouldBlockMobileWebViewNavigationRequest,
+} from './webViewPolicy';
 
 function buildHostBridgeMessageScript(message: unknown) {
   return `window.dispatchEvent(new MessageEvent('message', { data: ${JSON.stringify(
@@ -175,6 +178,10 @@ export default function ShellApp() {
   };
 
   const handleShouldStartLoad = (request: { url: string }) => {
+    if (shouldBlockMobileWebViewNavigationRequest(request)) {
+      return false;
+    }
+
     if (shouldOpenInMobileShellWebView(request.url, allowedWebOrigin)) {
       return true;
     }
@@ -201,6 +208,7 @@ export default function ShellApp() {
       .then(injectNetworkStatusEvent)
       .catch(() => undefined);
   };
+  const handleBlockedFileDownload = () => undefined;
 
   return (
     <SafeAreaProvider>
@@ -224,7 +232,7 @@ export default function ShellApp() {
           sharedCookiesEnabled={false}
           webviewDebuggingEnabled={false}
           injectedJavaScriptBeforeContentLoaded={BLOCK_WEBVIEW_DOWNLOAD_SCRIPT}
-          onFileDownload={() => undefined}
+          onFileDownload={handleBlockedFileDownload}
           onMessage={handleMessage}
           onContentProcessDidTerminate={reloadCurrentWebView}
           onRenderProcessGone={reloadCurrentWebView}

apps/mobile-shell/src/shell/webViewPolicy.test.ts

@@ -1,16 +1,140 @@
-import { describe, expect, test } from 'vitest';
+/* @vitest-environment jsdom */
 
-import { BLOCK_WEBVIEW_DOWNLOAD_SCRIPT } from './webViewPolicy';
+import { afterEach, beforeEach, describe, expect, test, vi } from 'vitest';
+
+import {
+  BLOCK_WEBVIEW_DOWNLOAD_SCRIPT,
+  shouldBlockMobileWebViewDownloadUrl,
+  shouldBlockMobileWebViewNavigationRequest,
+} from './webViewPolicy';
 
 describe('BLOCK_WEBVIEW_DOWNLOAD_SCRIPT', () => {
-  test('阻断 WebView 内的网页下载链接', () => {
-    expect(BLOCK_WEBVIEW_DOWNLOAD_SCRIPT).toContain(
-      "element.tagName === 'A'",
-    );
-    expect(BLOCK_WEBVIEW_DOWNLOAD_SCRIPT).toContain(
-      "element.hasAttribute('download')",
-    );
-    expect(BLOCK_WEBVIEW_DOWNLOAD_SCRIPT).toContain('event.preventDefault()');
+  const originalOpen = window.open;
+  const originalAnchorClick = HTMLAnchorElement.prototype.click;
+
+  beforeEach(() => {
+    document.body.innerHTML = '';
+    window.open = vi.fn(() => null) as typeof window.open;
+    HTMLAnchorElement.prototype.click = originalAnchorClick;
+    window.eval(BLOCK_WEBVIEW_DOWNLOAD_SCRIPT);
+  });
+
+  afterEach(() => {
+    document.body.innerHTML = '';
+    window.open = originalOpen;
+    HTMLAnchorElement.prototype.click = originalAnchorClick;
+    vi.restoreAllMocks();
+  });
+
+  test('保留 WebView 注入脚本返回值', () => {
     expect(BLOCK_WEBVIEW_DOWNLOAD_SCRIPT.trim()).toMatch(/true;$/);
   });
+
+  test('阻断嵌套元素触发的下载链接点击', () => {
+    document.body.innerHTML = `
+      <a href="/asset.png" download target="_blank">
+        <span id="nested-download-target">保存</span>
+      </a>
+    `;
+    const target = document.getElementById('nested-download-target');
+    expect(target).toBeTruthy();
+
+    const event = new MouseEvent('click', {
+      bubbles: true,
+      cancelable: true,
+    });
+    const allowed = target?.dispatchEvent(event);
+
+    expect(allowed).toBe(false);
+    expect(event.defaultPrevented).toBe(true);
+  });
+
+  test('放行普通同源页面链接点击', () => {
+    document.body.innerHTML = `
+      <a href="#section">
+        <span id="nested-page-target">打开</span>
+      </a>
+    `;
+    const target = document.getElementById('nested-page-target');
+    expect(target).toBeTruthy();
+
+    const event = new MouseEvent('click', {
+      bubbles: true,
+      cancelable: true,
+    });
+    const allowed = target?.dispatchEvent(event);
+
+    expect(allowed).toBe(true);
+    expect(event.defaultPrevented).toBe(false);
+  });
+
+  test('阻断危险下载协议的窗口打开', () => {
+    const opened = window.open('blob:https://app.genarrative.world/file-id');
+
+    expect(opened).toBeNull();
+  });
+
+  test('阻断程序化下载链接点击', () => {
+    const originalClickSpy = vi.spyOn(
+      HTMLAnchorElement.prototype,
+      'click',
+    );
+    window.eval(BLOCK_WEBVIEW_DOWNLOAD_SCRIPT);
+    const anchor = document.createElement('a');
+    anchor.href = 'data:text/plain;base64,SGVsbG8=';
+    anchor.download = 'hello.txt';
+
+    anchor.click();
+
+    expect(originalClickSpy).not.toHaveBeenCalled();
+  });
+});
+
+describe('shouldBlockMobileWebViewDownloadUrl', () => {
+  test('识别不能进入移动壳 WebView 的下载协议', () => {
+    expect(
+      shouldBlockMobileWebViewDownloadUrl(
+        'blob:https://app.genarrative.world/file-id',
+      ),
+    ).toBe(true);
+    expect(shouldBlockMobileWebViewDownloadUrl('data:text/plain,hello')).toBe(
+      true,
+    );
+    expect(shouldBlockMobileWebViewDownloadUrl('file:///tmp/export.png')).toBe(
+      true,
+    );
+    expect(
+      shouldBlockMobileWebViewDownloadUrl(
+        'filesystem:https://app.genarrative.world/temporary/export.png',
+      ),
+    ).toBe(true);
+  });
+
+  test('放行普通网页和系统外链协议', () => {
+    expect(
+      shouldBlockMobileWebViewDownloadUrl(
+        'https://app.genarrative.world/works/detail?work=PZ-1',
+      ),
+    ).toBe(false);
+    expect(shouldBlockMobileWebViewDownloadUrl('/creation/puzzle')).toBe(false);
+    expect(shouldBlockMobileWebViewDownloadUrl('mailto:hi@example.com')).toBe(
+      false,
+    );
+    expect(shouldBlockMobileWebViewDownloadUrl('tel:+12345678')).toBe(false);
+  });
+});
+
+describe('shouldBlockMobileWebViewNavigationRequest', () => {
+  test('在 WebView 导航前拦截下载协议', () => {
+    expect(
+      shouldBlockMobileWebViewNavigationRequest({
+        url: 'blob:https://app.genarrative.world/file-id',
+      }),
+    ).toBe(true);
+    expect(
+      shouldBlockMobileWebViewNavigationRequest({
+        url: 'https://app.genarrative.world/creation/puzzle',
+      }),
+    ).toBe(false);
+  });
 });

apps/mobile-shell/src/shell/webViewPolicy.ts

@@ -1,13 +1,116 @@
+const MOBILE_WEBVIEW_BLOCKED_DOWNLOAD_PROTOCOLS = new Set([
+  'blob:',
+  'data:',
+  'file:',
+  'filesystem:',
+]);
+
+export type MobileWebViewNavigationRequest = {
+  url?: string | null;
+};
+
+export function shouldBlockMobileWebViewDownloadUrl(
+  rawUrl: string | null | undefined,
+) {
+  if (!rawUrl) {
+    return false;
+  }
+
+  try {
+    return MOBILE_WEBVIEW_BLOCKED_DOWNLOAD_PROTOCOLS.has(
+      new URL(rawUrl, 'https://app.genarrative.world/').protocol,
+    );
+  } catch {
+    return false;
+  }
+}
+
+export function shouldBlockMobileWebViewNavigationRequest(
+  request: MobileWebViewNavigationRequest,
+) {
+  return shouldBlockMobileWebViewDownloadUrl(request.url);
+}
+
 export const BLOCK_WEBVIEW_DOWNLOAD_SCRIPT = `
-document.addEventListener('click', function(event) {
-  var element = event.target;
-  while (element && element !== document) {
-    if (element.tagName === 'A' && element.hasAttribute('download')) {
-      event.preventDefault();
+(function() {
+  var blockedDownloadProtocols = {
+    'blob:': true,
+    'data:': true,
+    'file:': true,
+    'filesystem:': true
+  };
+
+  function shouldBlockDownloadUrl(rawUrl) {
+    if (typeof rawUrl !== 'string') {
+      return false;
+    }
+
+    try {
+      return blockedDownloadProtocols[new URL(rawUrl, window.location.href).protocol] === true;
+    } catch (error) {
       return false;
     }
-    element = element.parentNode;
   }
-}, true);
+
+  function findDownloadAnchor(target) {
+    if (!target) {
+      return null;
+    }
+
+    if (typeof target.closest === 'function') {
+      return target.closest('a');
+    }
+
+    var element = target;
+    while (element && element !== document) {
+      if (element.tagName === 'A') {
+        return element;
+      }
+      element = element.parentNode;
+    }
+
+    return null;
+  }
+
+  function shouldBlockAnchor(anchor) {
+    return Boolean(
+      anchor &&
+        (anchor.hasAttribute('download') || shouldBlockDownloadUrl(anchor.href))
+    );
+  }
+
+  function blockDownloadEvent(event) {
+    event.preventDefault();
+    event.stopImmediatePropagation();
+    event.stopPropagation();
+    return false;
+  }
+
+  document.addEventListener('click', function(event) {
+    if (shouldBlockAnchor(findDownloadAnchor(event.target))) {
+      return blockDownloadEvent(event);
+    }
+  }, true);
+
+  var originalOpen = window.open;
+  window.open = function(url) {
+    if (shouldBlockDownloadUrl(url)) {
+      return null;
+    }
+
+    return originalOpen.apply(window, arguments);
+  };
+
+  if (window.HTMLAnchorElement && HTMLAnchorElement.prototype.click) {
+    var originalAnchorClick = HTMLAnchorElement.prototype.click;
+    HTMLAnchorElement.prototype.click = function() {
+      if (shouldBlockAnchor(this)) {
+        return undefined;
+      }
+
+      return originalAnchorClick.apply(this, arguments);
+    };
+  }
+})();
 true;
 `;

docs/project-memory/shared-memory/decision-log.md

@@ -2506,3 +2506,10 @@
 - 决策：新增 `apps/desktop-shell/src-tauri/src/shell/menu.rs` 注册 Tauri 应用菜单。应用菜单只复用宿主壳级显示主窗口、刷新主窗口和退出应用动作；编辑菜单和窗口菜单使用 Tauri 原生预定义项承接剪切、复制、粘贴、全选、最小化、最大化和关闭窗口。该能力不进入 HostBridge capability，不开放菜单 API、shell API 或任意窗口控制给 H5；菜单注册失败直接阻断启动，避免生产桌面壳缺少系统菜单仍静默运行。
 - 影响范围：`apps/desktop-shell/src-tauri/src/main.rs`、`apps/desktop-shell/src-tauri/src/shell/menu.rs`、`apps/desktop-shell/src-tauri/src/shell/tray.rs`、`apps/desktop-shell/scripts/check-config.mjs`、`scripts/check-native-shells.mjs`、Expo / Tauri HostBridge 方案文档。
 - 验证方式：`npm run desktop-shell:typecheck`、`npm run desktop-shell:test`、`npm run desktop-shell:build -- --no-bundle`、`npm run check:native-shells`、`npm run typecheck -- --pretty false`、`npm run check:encoding`、`git diff --check`。
+
+## 2026-06-18 移动壳 WebView 下载协议阻断
+
+- 背景：移动壳已经通过 WebView 注入脚本阻断 `<a download>` 点击，并丢弃 iOS `onFileDownload` 事件；但 `blob:`、`data:`、`file:`、`filesystem:` 等下载协议导航仍可能在 `onShouldStartLoadWithRequest` 中进入普通同源 / 外链分流，脚本创建的下载链接也缺少行为级测试覆盖。
+- 决策：`apps/mobile-shell/src/shell/webViewPolicy.ts` 统一承接移动壳下载策略，注入脚本阻断下载链接点击、危险下载协议链接、`window.open` 下载 URL 和程序化 anchor click；`ShellApp` 在同源 / 外链分流前调用 `shouldBlockMobileWebViewNavigationRequest(...)`，命中 `blob:`、`data:`、`file:` 或 `filesystem:` 直接拒绝，不进入带完整 HostBridge 的 WebView，也不交给系统外部应用。移动端文件保存仍只能走受控 `file.exportText`、`file.exportImage`、`file.exportAudio` HostBridge method。
+- 影响范围：`apps/mobile-shell/src/shell/webViewPolicy.ts`、`apps/mobile-shell/src/shell/webViewPolicy.test.ts`、`apps/mobile-shell/src/shell/ShellApp.tsx`、`apps/mobile-shell/scripts/check-config.mjs`、Expo / Tauri HostBridge 方案文档。
+- 验证方式：`npm run mobile-shell:test -- src/shell/webViewPolicy.test.ts`、`npm run mobile-shell:typecheck`、`npm run check:native-shells`、`npm run typecheck -- --pretty false`、`npm run check:encoding`、`git diff --check`。

docs/【前端架构】ExpoReactNative与Tauri宿主壳方案-2026-06-17.md

@@ -250,7 +250,7 @@ GameBridge 禁止：
 - Tauri 主 WebView 禁止默认下载落盘；桌面文件保存只能通过受控 HostBridge 导出能力进入系统保存对话框。
 - Tauri 主 WebView 禁止默认打开 DevTools；不得通过配置或 Cargo feature 为分发壳启用浏览器检查器。
 - RN WebView 禁止打开任意 URL 后仍保留完整 HostBridge；跳外链只允许 `http:`、`https:`、`mailto:`、`tel:`，并使用系统浏览器或降级能力，危险协议直接阻断。
-- RN WebView 禁止网页自动下载和 `<a download>` 直接落盘；移动端文件保存只能通过 `file.exportText`、`file.exportImage`、`file.exportAudio` 等受控 HostBridge method 进入系统分享 / 保存面板。
+- RN WebView 禁止网页自动下载、下载协议导航和 `<a download>` 直接落盘；移动端文件保存只能通过 `file.exportText`、`file.exportImage`、`file.exportAudio` 等受控 HostBridge method 进入系统分享 / 保存面板。
 - Expo 移动壳的通知能力只覆盖即时本地通知；Android 包配置必须阻断重启后通知恢复和精确定时权限，前端代码不得注册 Expo push token、远程推送监听或通知响应跳转流程。
 - AI sandbox iframe 必须使用独立 CSP、`sandbox` 属性和单独 GameBridge allowlist。
 
@@ -416,7 +416,7 @@ GameBridge 禁止：
 
 2026-06-18 追加：移动壳 WebView 原生安全开关显式收紧。`react-native-webview` 只加载同源主站入口，保留 JS 和 DOM storage 以运行现有 H5，但禁用 JS 自动开窗、多窗口、文件访问、file URL 跨源访问、HTTPS 页面加载 HTTP 混合内容、第三方 Cookie、共享 Cookie 和 WebView 远程调试；外链继续只允许 `http:`、`https:`、`mailto:`、`tel:` 离开 WebView 交给系统。`apps/mobile-shell/scripts/check-config.mjs` 和 `navigation.test.ts` 会覆盖这些壳边界，避免后续为单个页面调试把完整 HostBridge 暴露给外域页面。
 
-2026-06-18 追加：移动壳 WebView 默认下载路径显式关闭。壳层在 WebView 注入脚本中阻断 `<a download>` 点击，iOS `onFileDownload` 事件只丢弃不落盘，Android 包配置阻断外部存储读写、管理外部存储和请求安装包权限；H5 文本、图片、音频保存继续只能走 `file.exportText`、`file.exportImage`、`file.exportAudio` 的受控 HostBridge 导出能力。
+2026-06-18 追加：移动壳 WebView 默认下载路径显式关闭。壳层在 WebView 注入脚本中阻断 `<a download>` 点击、危险下载协议链接、`window.open` 下载 URL 和程序化 anchor click；`onShouldStartLoadWithRequest` 会在同源 / 外链分流前拒绝 `blob:`、`data:`、`file:` 和 `filesystem:` 导航，避免下载 URL 进入带完整 HostBridge 的 WebView 或交给系统外部应用；iOS `onFileDownload` 事件只丢弃不落盘，Android 包配置阻断外部存储读写、管理外部存储和请求安装包权限；H5 文本、图片、音频保存继续只能走 `file.exportText`、`file.exportImage`、`file.exportAudio` 的受控 HostBridge 导出能力。
 
 2026-06-18 追加：移动壳 HostBridge 消息入口增加来源校验。`onMessage` 不只依赖导航拦截和 `originWhitelist`，还会读取 `event.nativeEvent.url`，只有同源主站页面才能进入 `handleMobileHostBridgeMessage`；`about:blank`、外域 URL、协议降级或危险协议页面发来的消息全部丢弃，不返回 HostBridge 错误细节。该校验与 `navigation.openNativePage` 共用同源规则，防止历史中间页或异常页面在带完整 HostBridge 的 WebView 中发起宿主能力请求。