/** * This file is part of Haketilo. * * Function: Enforcing script blocking rules on a given page, working from a * content script. * * Copyright (C) 2021,2022 Wojtek Kosior * Copyright (C) 2021 jahoti * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * As additional permission under GNU GPL version 3 section 7, you * may distribute forms of that code without the copy of the GNU * GPL normally required by section 4, provided you include this * license notice and, in case of non-source distribution, a URL * through which recipients can access the Corresponding Source. * If you modify file(s) with this exception, you may extend this * exception to your version of the file(s), but you are not * obligated to do so. If you do not wish to do so, delete this * exception statement from your version. * * As a special exception to the GPL, any HTML file which merely * makes function calls to this code, and for that purpose * includes it by reference shall be deemed a separate work for * copyright law purposes. If you modify this code, you may extend * this exception to your version of the code, but you are not * obligated to do so. If you do not wish to do so, delete this * exception statement from your version. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . * * I, Wojtek Kosior, thereby promise not to sue for violation of this file's * license. Although I request that you do not make use of this code in a * proprietary program, I am not going to enforce this in court. */ #FROM common/misc.js IMPORT gen_nonce document.content_loaded = document.readyState === "complete"; const wait_loaded = e => e.content_loaded ? Promise.resolve() : new Promise(c => e.addEventListener("DOMContentLoaded", c, {once: true})); wait_loaded(document).then(() => document.content_loaded = true); /* * In the case of HTML documents: * 1. When injecting some payload we need to sanitize CSP tags before * they reach the document. * 2. Only tags inside are considered valid by the browser and * need to be considered. * 3. We want to detach from document, wait until its completes * loading, sanitize it and re-attach . * 4. We shall wait for anything to appear in or after and take that as * a sign has finished loading. * 5. Otherwise, getting the `DOMContentLoaded' event on the document shall also * be a sign that is fully loaded. */ function make_body_start_observer(DOM_element, waiting) { const observer = new MutationObserver(() => try_body_started(waiting)); observer.observe(DOM_element, {childList: true}); return observer; } function try_body_started(waiting) { const body = waiting.detached_html.querySelector("body"); if ((body && (body.firstChild || body.nextSibling)) || waiting.doc.documentElement.nextSibling) { finish_waiting(waiting); return true; } if (body && waiting.observers.length < 2) waiting.observers.push(make_body_start_observer(body, waiting)); } function finish_waiting(waiting) { if (waiting.finished) return; waiting.finished = true; waiting.observers.forEach(observer => observer.disconnect()); setTimeout(waiting.callback, 0); } function _wait_for_head(doc, detached_html, callback) { const waiting = {doc, detached_html, callback, observers: []}; if (try_body_started(waiting)) return; waiting.observers = [make_body_start_observer(detached_html, waiting)]; wait_loaded(doc).then(() => finish_waiting(waiting)); } function wait_for_head(doc, detached_html) { return new Promise(cb => _wait_for_head(doc, detached_html, cb)); } const blocked_str = "blocked"; function block_attribute(node, attr, ns=null, replace_with=null) { const [hasa, geta, seta, rema] = ["has", "get", "set", "remove"] .map(m => (n, ...args) => typeof ns === "string" ? n[`${m}AttributeNS`](ns, ...args) : n[`${m}Attribute`](...args)); /* * Disabling attributes by prepending `blocked-' allows them to still be * relatively easily accessed in case they contain some useful data. */ const construct_name = [attr]; while (hasa(node, construct_name.join(""))) construct_name.unshift(blocked_str); while (construct_name.length > 1) { construct_name.shift(); const name = construct_name.join(""); seta(node, `${blocked_str}-${name}`, geta(node, name)); } rema(node, attr); if (replace_with !== null) seta(node, attr, replace_with); } /* * Used to disable `