gecko-dev/toolkit/modules/IgnoreLists.jsm

99 строки
2.9 KiB
JavaScript

/* 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.import(
"resource://gre/modules/XPCOMUtils.jsm"
);
XPCOMUtils.defineLazyModuleGetters(this, {
RemoteSettings: "resource://services-settings/remote-settings.js",
RemoteSettingsClient: "resource://services-settings/RemoteSettingsClient.jsm",
});
var EXPORTED_SYMBOLS = ["IgnoreLists"];
const SETTINGS_IGNORELIST_KEY = "hijack-blocklists";
class IgnoreListsManager {
async init() {
if (!this._ignoreListSettings) {
this._ignoreListSettings = RemoteSettings(SETTINGS_IGNORELIST_KEY);
}
}
async getAndSubscribe(listener) {
await this.init();
// Trigger a get of the initial value.
const settings = await this._getIgnoreList();
// Listen for future updates after we first get the values.
this._ignoreListSettings.on("sync", listener);
return settings;
}
unsubscribe(listener) {
if (!this._ignoreListSettings) {
return;
}
this._ignoreListSettings.off("sync", listener);
}
async _getIgnoreList() {
if (this._getSettingsPromise) {
return this._getSettingsPromise;
}
const settings = await (this._getSettingsPromise = this._getIgnoreListSettings());
delete this._getSettingsPromise;
return settings;
}
/**
* Obtains the current ignore list from remote settings. This includes
* verifying the signature of the ignore list within the database.
*
* If the signature in the database is invalid, the database will be wiped
* and the stored dump will be used, until the settings next update.
*
* Note that this may cause a network check of the certificate, but that
* should generally be quick.
*
* @param {boolean} [firstTime]
* Internal boolean to indicate if this is the first time check or not.
* @returns {array}
* An array of objects in the database, or an empty array if none
* could be obtained.
*/
async _getIgnoreListSettings(firstTime = true) {
let result = [];
try {
result = await this._ignoreListSettings.get({
verifySignature: true,
});
} catch (ex) {
if (
ex instanceof RemoteSettingsClient.InvalidSignatureError &&
firstTime
) {
// The local database is invalid, try and reset it.
const collection = await this._ignoreListSettings.openCollection();
await collection.clear();
await collection.db.close();
// Now call this again.
return this._getIgnoreListSettings(false);
}
// Don't throw an error just log it, just continue with no data, and hopefully
// a sync will fix things later on.
Cu.reportError(ex);
}
return result;
}
}
const IgnoreLists = new IgnoreListsManager();