Bug 1575625 - Make Cache API available to webextensions (moz-extension:// schemas) r=asuth,rpl

Make Cache API available to webextensions (moz-extension:// schemas)

Differential Revision: https://phabricator.services.mozilla.com/D114054

dom/cache/CacheStorage.cpp

@@ -112,11 +112,7 @@ bool IsTrusted(const PrincipalInfo& aPrincipalInfo, bool aTestingPrefEnabled) {
 
   const nsAutoCString scheme(Substring(flatURL, schemePos, schemeLen));
   if (scheme.LowerCaseEqualsLiteral("https") ||
-      scheme.LowerCaseEqualsLiteral("file")) {
-    return true;
-  }
-
-  if (StaticPrefs::extensions_backgroundServiceWorker_enabled_AtStartup() &&
+      scheme.LowerCaseEqualsLiteral("file") ||
       scheme.LowerCaseEqualsLiteral("moz-extension")) {
     return true;
   }

toolkit/components/extensions/Extension.jsm

@@ -379,7 +379,7 @@ var ExtensionAddonObserver = {
         ExtensionStorage.clear(addon.id, { shouldNotifyListeners: false })
       );
 
-      // Clear any IndexedDB storage created by the extension
+      // Clear any IndexedDB and Cache API storage created by the extension.
       // If LSNG is enabled, this also clears localStorage.
       Services.qms.clearStoragesForPrincipal(principal);
 

toolkit/components/extensions/test/browser/browser_ext_background_serviceworker.js

@@ -105,8 +105,8 @@ add_task(async function test_serviceWorker_register_guarded_by_pref() {
 });
 
 add_task(async function test_cache_api_allowed() {
-  // Verify that Cache API support for moz-extension url availability is also
-  // conditioned by the extensions.backgroundServiceWorker.enabled pref.
+  // Verify that Cache API support for moz-extension url availability is
+  // conditioned only by the extensions.backgroundServiceWorker.enabled pref.
   // NOTE: the scenario with backgroundServiceWorkeEnable set to false
   // is part of "browser_ext_background_serviceworker_pref_disabled.js".
   const extension = ExtensionTestUtils.loadExtension({

toolkit/components/extensions/test/browser/browser_ext_background_serviceworker_pref_disabled.js

@@ -100,20 +100,23 @@ add_task(async function test_cache_api_disallowed() {
   const extension = ExtensionTestUtils.loadExtension({
     async background() {
       try {
-        await window.caches.open("test-cache-api");
-        browser.test.fail(
-          `An extension page should not be allowed to use the Cache API successfully`
+        const cache = await window.caches.open("test-cache-api");
+        let url = browser.runtime.getURL("file.txt");
+        await browser.test.assertRejects(
+          cache.add(url),
+          new RegExp(`Cache.add: Request URL ${url} must be either`),
+          "Got the expected rejections on calling cache.add with a moz-extension:// url"
         );
       } catch (err) {
-        browser.test.assertEq(
-          String(err),
-          "SecurityError: The operation is insecure.",
-          "Got the expected error on registering a service worker from a script"
-        );
+        browser.test.fail(`Unexpected error on using Cache API: ${err}`);
+        throw err;
       } finally {
         browser.test.sendMessage("test-cache-api-disallowed");
       }
     },
+    files: {
+      "file.txt": "file content",
+    },
   });
 
   await extension.startup();

toolkit/components/extensions/test/xpcshell/test_ext_cache_api.js

@@ -0,0 +1,141 @@
+/* -*- Mode: indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim: set sts=2 sw=2 et tw=80: */
+
+"use strict";
+
+AddonTestUtils.init(this);
+AddonTestUtils.createAppInfo(
+  "xpcshell@tests.mozilla.org",
+  "XPCShell",
+  "1",
+  "42"
+);
+
+const server = createHttpServer({
+  hosts: ["example.com", "anotherdomain.com"],
+});
+server.registerPathHandler("/dummy", (request, response) => {
+  response.setStatusLine(request.httpVersion, 200, "OK");
+  response.setHeader("Content-Type", "text/html", false);
+  response.write("test_ext_cache_api.js");
+});
+
+add_task(async function test_cache_api_http_resource_allowed() {
+  async function background() {
+    try {
+      const BASE_URL = `http://example.com/dummy`;
+
+      const cache = await window.caches.open("test-cache-api");
+      browser.test.assertTrue(
+        await window.caches.has("test-cache-api"),
+        "CacheStorage.has should resolve to true"
+      );
+
+      // Test that adding and requesting cached http urls
+      // works as well.
+      await cache.add(BASE_URL);
+      browser.test.assertEq(
+        "test_ext_cache_api.js",
+        await cache.match(BASE_URL).then(res => res.text()),
+        "Got the expected content from the cached http url"
+      );
+
+      // Test that the http urls that the cache API is allowed
+      // to fetch and cache are limited by the host permissions
+      // associated to the extensions (same as when the extension
+      // for fetch from those urls using fetch or XHR).
+      await browser.test.assertRejects(
+        cache.add(`http://anotherdomain.com/dummy`),
+        "NetworkError when attempting to fetch resource.",
+        "Got the expected rejection of requesting an http not allowed by host permissions"
+      );
+
+      // Test that deleting the cache storage works as expected.
+      browser.test.assertTrue(
+        await window.caches.delete("test-cache-api"),
+        "Cache deleted successfully"
+      );
+      browser.test.assertTrue(
+        !(await window.caches.has("test-cache-api")),
+        "CacheStorage.has should resolve to false"
+      );
+    } catch (err) {
+      browser.test.fail(`Unexpected error on using Cache API: ${err}`);
+      throw err;
+    } finally {
+      browser.test.sendMessage("test-cache-api-allowed");
+    }
+  }
+
+  // Verify that Cache API support for http urls is available
+  // regardless of extensions.backgroundServiceWorker.enabled pref.
+  const extension = ExtensionTestUtils.loadExtension({
+    manifest: { permissions: ["http://example.com/*"] },
+    background,
+  });
+
+  await extension.startup();
+
+  await extension.awaitMessage("test-cache-api-allowed");
+  await extension.unload();
+});
+
+add_task(async function test_cache_storage_evicted_on_addon_uninstalled() {
+  async function background() {
+    try {
+      const BASE_URL = `http://example.com/dummy`;
+
+      const cache = await window.caches.open("test-cache-api");
+      browser.test.assertTrue(
+        await window.caches.has("test-cache-api"),
+        "CacheStorage.has should resolve to true"
+      );
+
+      // Test that adding and requesting cached http urls
+      // works as well.
+      await cache.add(BASE_URL);
+      browser.test.assertEq(
+        "test_ext_cache_api.js",
+        await cache.match(BASE_URL).then(res => res.text()),
+        "Got the expected content from the cached http url"
+      );
+    } catch (err) {
+      browser.test.fail(`Unexpected error on using Cache API: ${err}`);
+      throw err;
+    } finally {
+      browser.test.sendMessage("cache-storage-created");
+    }
+  }
+
+  const extension = ExtensionTestUtils.loadExtension({
+    manifest: { permissions: ["http://example.com/*"] },
+    background,
+    // Necessary to be sure the expected extension stored data cleanup callback
+    // will be called when the extension is uninstalled from an AddonManager
+    // perspective.
+    useAddonManager: "temporary",
+  });
+
+  await AddonTestUtils.promiseStartupManager();
+  await extension.startup();
+  await extension.awaitMessage("cache-storage-created");
+
+  const extURL = `moz-extension://${extension.extension.uuid}`;
+  const extPrincipal = Services.scriptSecurityManager.createContentPrincipal(
+    Services.io.newURI(extURL),
+    {}
+  );
+  let extCacheStorage = new CacheStorage("content", extPrincipal);
+
+  ok(
+    await extCacheStorage.has("test-cache-api"),
+    "Got the expected extension cache storage"
+  );
+
+  await extension.unload();
+
+  ok(
+    !(await extCacheStorage.has("test-cache-api")),
+    "The extension cache storage data should have been evicted on addon uninstall"
+  );
+});

toolkit/components/extensions/test/xpcshell/xpcshell-common.ini

@@ -34,6 +34,7 @@ skip-if = appname == "thunderbird" || os == "android"
 [test_ext_browsingData.js]
 [test_ext_browsingData_cookies_cache.js]
 [test_ext_browsingData_cookies_cookieStoreId.js]
+[test_ext_cache_api.js]
 [test_ext_captivePortal.js]
 # As with test_captive_portal_service.js, we use the same limits here.
 skip-if = appname == "thunderbird" || os == "android" || (os == "mac" && debug) # CP service is disabled on Android, macosx1014/debug due to 1564534