1 files changed, 246 insertions, 0 deletions
diff --git a/toolkit/components/antitracking/URLQueryStrippingListService.jsm b/toolkit/components/antitracking/URLQueryStrippingListService.jsm
new file mode 100644
index 0000000000..c8682f3121
--- /dev/null
+++ b/toolkit/components/antitracking/URLQueryStrippingListService.jsm
@@ -0,0 +1,246 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const { XPCOMUtils } = ChromeUtils.importESModule(
+  "resource://gre/modules/XPCOMUtils.sys.mjs"
+);
+
+const lazy = {};
+
+XPCOMUtils.defineLazyModuleGetters(lazy, {
+  RemoteSettings: "resource://services-settings/remote-settings.js",
+});
+
+const COLLECTION_NAME = "query-stripping";
+const SHARED_DATA_KEY = "URLQueryStripping";
+
+const PREF_STRIP_LIST_NAME = "privacy.query_stripping.strip_list";
+const PREF_ALLOW_LIST_NAME = "privacy.query_stripping.allow_list";
+const PREF_TESTING_ENABLED = "privacy.query_stripping.testing";
+
+class URLQueryStrippingListService {
+  constructor() {
+    this.classID = Components.ID("{afff16f0-3fd2-4153-9ccd-c6d9abd879e4}");
+    this.QueryInterface = ChromeUtils.generateQI([
+      "nsIURLQueryStrippingListService",
+    ]);
+    this.observers = new Set();
+    this.prefStripList = new Set();
+    this.prefAllowList = new Set();
+    this.remoteStripList = new Set();
+    this.remoteAllowList = new Set();
+    this.isParentProcess =
+      Services.appinfo.processType === Services.appinfo.PROCESS_TYPE_DEFAULT;
+  }
+
+  async _init() {
+    // We can only access the remote settings in the parent process. For content
+    // processes, we will use sharedData to sync the list to content processes.
+    if (this.isParentProcess) {
+      let rs = lazy.RemoteSettings(COLLECTION_NAME);
+
+      rs.on("sync", event => {
+        let {
+          data: { current },
+        } = event;
+        this._onRemoteSettingsUpdate(current);
+      });
+
+      // Get the initially available entries for remote settings.
+      let entries;
+      try {
+        entries = await rs.get();
+      } catch (e) {}
+      this._onRemoteSettingsUpdate(entries || []);
+    } else {
+      // Register the message listener for the remote settings update from the
+      // sharedData.
+      Services.cpmm.sharedData.addEventListener("change", this);
+
+      // Get the remote settings data from the shared data.
+      let data = this._getListFromSharedData();
+
+      this._onRemoteSettingsUpdate(data);
+    }
+
+    // Get the list from pref.
+    this._onPrefUpdate(
+      PREF_STRIP_LIST_NAME,
+      Services.prefs.getStringPref(PREF_STRIP_LIST_NAME, "")
+    );
+    this._onPrefUpdate(
+      PREF_ALLOW_LIST_NAME,
+      Services.prefs.getStringPref(PREF_ALLOW_LIST_NAME, "")
+    );
+
+    Services.prefs.addObserver(PREF_STRIP_LIST_NAME, this);
+    Services.prefs.addObserver(PREF_ALLOW_LIST_NAME, this);
+
+    Services.obs.addObserver(this, "xpcom-shutdown");
+  }
+
+  async _shutdown() {
+    Services.obs.removeObserver(this, "xpcom-shutdown");
+    Services.prefs.removeObserver(PREF_STRIP_LIST_NAME, this);
+    Services.prefs.removeObserver(PREF_ALLOW_LIST_NAME, this);
+  }
+
+  _onRemoteSettingsUpdate(entries) {
+    this.remoteStripList.clear();
+    this.remoteAllowList.clear();
+
+    for (let entry of entries) {
+      for (let item of entry.stripList) {
+        this.remoteStripList.add(item);
+      }
+
+      for (let item of entry.allowList) {
+        this.remoteAllowList.add(item);
+      }
+    }
+
+    // Because only the parent process will get the remote settings update, so
+    // we will sync the list to the shared data so that content processes can
+    // get the list.
+    if (this.isParentProcess) {
+      Services.ppmm.sharedData.set(SHARED_DATA_KEY, {
+        stripList: this.remoteStripList,
+        allowList: this.remoteAllowList,
+      });
+
+      if (Services.prefs.getBoolPref(PREF_TESTING_ENABLED, false)) {
+        Services.ppmm.sharedData.flush();
+      }
+    }
+
+    this._notifyObservers();
+  }
+
+  _onPrefUpdate(pref, value) {
+    switch (pref) {
+      case PREF_STRIP_LIST_NAME:
+        this.prefStripList = new Set(value ? value.split(" ") : []);
+        break;
+
+      case PREF_ALLOW_LIST_NAME:
+        this.prefAllowList = new Set(value ? value.split(",") : []);
+        break;
+
+      default:
+        Cu.reportError(`Unexpected pref name ${pref}`);
+        return;
+    }
+
+    this._notifyObservers();
+  }
+
+  async _ensureInit() {
+    await this._initPromise;
+  }
+
+  _getListFromSharedData() {
+    let data = Services.cpmm.sharedData.get(SHARED_DATA_KEY);
+
+    return data ? [data] : [];
+  }
+
+  _notifyObservers(observer) {
+    let stripEntries = new Set([
+      ...this.prefStripList,
+      ...this.remoteStripList,
+    ]);
+    let allowEntries = new Set([
+      ...this.prefAllowList,
+      ...this.remoteAllowList,
+    ]);
+    let stripEntriesAsString = Array.from(stripEntries)
+      .join(" ")
+      .toLowerCase();
+    let allowEntriesAsString = Array.from(allowEntries)
+      .join(",")
+      .toLowerCase();
+
+    let observers = observer ? [observer] : this.observers;
+
+    for (let obs of observers) {
+      obs.onQueryStrippingListUpdate(
+        stripEntriesAsString,
+        allowEntriesAsString
+      );
+    }
+  }
+
+  init() {
+    if (this.initialized) {
+      return;
+    }
+
+    this.initialized = true;
+    this._initPromise = this._init();
+  }
+
+  registerAndRunObserver(observer) {
+    let addAndRunObserver = _ => {
+      this.observers.add(observer);
+      this._notifyObservers(observer);
+    };
+
+    if (this.initialized) {
+      addAndRunObserver();
+      return;
+    }
+
+    this._ensureInit().then(addAndRunObserver);
+  }
+
+  unregisterObserver(observer) {
+    this.observers.delete(observer);
+  }
+
+  clearLists() {
+    if (!this.isParentProcess) {
+      return;
+    }
+
+    // Clear the lists of remote settings.
+    this._onRemoteSettingsUpdate([]);
+
+    // Clear the user pref for the strip list. The pref change observer will
+    // handle the rest of the work.
+    Services.prefs.clearUserPref(PREF_STRIP_LIST_NAME);
+    Services.prefs.clearUserPref(PREF_ALLOW_LIST_NAME);
+  }
+
+  observe(subject, topic, data) {
+    switch (topic) {
+      case "xpcom-shutdown":
+        this._shutdown();
+        break;
+      case "nsPref:changed":
+        let prefValue = Services.prefs.getStringPref(data, "");
+        this._onPrefUpdate(data, prefValue);
+        break;
+      default:
+        Cu.reportError(`Unexpected event ${topic}`);
+    }
+  }
+
+  handleEvent(event) {
+    if (event.type != "change") {
+      return;
+    }
+
+    if (!event.changedKeys.includes(SHARED_DATA_KEY)) {
+      return;
+    }
+
+    let data = this._getListFromSharedData();
+    this._onRemoteSettingsUpdate(data);
+    this._notifyObservers();
+  }
+}
+
+var EXPORTED_SYMBOLS = ["URLQueryStrippingListService"];