From 96068ada37bfa1d7e6485551138ba36600664caf Mon Sep 17 00:00:00 2001 From: Wojtek Kosior Date: Sat, 20 Nov 2021 18:29:59 +0100 Subject: replace cookies with synchronous XmlHttpRequest as policy smuggling method. Note: this breaks Mozilla port of Haketilo. Synchronous XmlHttpRequest doesn't work as well there. This will be fixed with dynamically-registered content scripts later. --- content/activity_info_server.js | 4 +- content/main.js | 138 ++++++++++++---------------------------- content/page_actions.js | 27 ++++---- 3 files changed, 56 insertions(+), 113 deletions(-) (limited to 'content') diff --git a/content/activity_info_server.js b/content/activity_info_server.js index d1dfe36..aa92b75 100644 --- a/content/activity_info_server.js +++ b/content/activity_info_server.js @@ -42,7 +42,9 @@ function report_script(script_data) function report_settings(settings) { - report_activity("settings", settings); + const settings_clone = {}; + Object.assign(settings_clone, settings) + report_activity("settings", settings_clone); } function report_document_type(is_html) diff --git a/content/main.js b/content/main.js index cec9943..ce1ff7a 100644 --- a/content/main.js +++ b/content/main.js @@ -11,15 +11,15 @@ /* * IMPORTS_START * IMPORT handle_page_actions - * IMPORT extract_signed - * IMPORT sign_data * IMPORT gen_nonce * IMPORT is_privileged_url + * IMPORT browser * IMPORT is_chrome * IMPORT is_mozilla * IMPORT start_activity_info_server * IMPORT make_csp_rule * IMPORT csp_header_regex + * IMPORT report_settings * IMPORTS_END */ @@ -29,69 +29,6 @@ const wait_loaded = e => e.content_loaded ? Promise.resolve() : wait_loaded(document).then(() => document.content_loaded = true); -function extract_cookie_policy(cookie, min_time) -{ - let best_result = {time: -1}; - let policy = null; - const extracted_signatures = []; - - for (const match of cookie.matchAll(/haketilo-(\w*)=([^;]*)/g)) { - const new_result = extract_signed(...match.slice(1, 3)); - if (new_result.fail) - continue; - - extracted_signatures.push(match[1]); - - if (new_result.time < Math.max(min_time, best_result.time)) - continue; - - /* This should succeed - it's our self-produced valid JSON. */ - const new_policy = JSON.parse(decodeURIComponent(new_result.data)); - if (new_policy.url !== document.URL) - continue; - - best_result = new_result; - policy = new_policy; - } - - return [policy, extracted_signatures]; -} - -function extract_url_policy(url, min_time) -{ - const [base_url, payload, anchor] = - /^([^#]*)#?([^#]*)(#?.*)$/.exec(url).splice(1, 4); - - const match = /^haketilo_([^_]+)_(.*)$/.exec(payload); - if (!match) - return [null, url]; - - const result = extract_signed(...match.slice(1, 3)); - if (result.fail) - return [null, url]; - - const original_url = base_url + anchor; - const policy = result.time < min_time ? null : - JSON.parse(decodeURIComponent(result.data)); - - return [policy.url === original_url ? policy : null, original_url]; -} - -function employ_nonhttp_policy(policy) -{ - if (!policy.allow) - return; - - policy.nonce = gen_nonce(); - const [base_url, target] = /^([^#]*)(#?.*)$/.exec(policy.url).slice(1, 3); - const encoded_policy = encodeURIComponent(JSON.stringify(policy)); - const payload = "haketilo_" + - sign_data(encoded_policy, new Date().getTime()).join("_"); - const resulting_url = `${base_url}#${payload}${target}`; - location.href = resulting_url; - location.reload(); -} - /* * In the case of HTML documents: * 1. When injecting some payload we need to sanitize CSP tags before @@ -306,7 +243,7 @@ http-equiv="Content-Security-Policy" content="${make_csp_rule(policy)}"\ start_data_urls_sanitizing(doc); } -async function disable_service_workers() +async function _disable_service_workers() { if (!navigator.serviceWorker) return; @@ -315,7 +252,7 @@ async function disable_service_workers() if (registrations.length === 0) return; - console.warn("Service Workers detected on this page! Unregistering and reloading"); + console.warn("Service Workers detected on this page! Unregistering and reloading."); try { await Promise.all(registrations.map(r => r.unregister())); @@ -327,50 +264,57 @@ async function disable_service_workers() return new Promise(() => 0); } -if (!is_privileged_url(document.URL)) { - let policy_received_callback = () => undefined; - let policy; - - /* Signature valid for half an hour. */ - const min_time = new Date().getTime() - 1800 * 1000; - - if (/^https?:/.test(document.URL)) { - let signatures; - [policy, signatures] = extract_cookie_policy(document.cookie, min_time); - for (const signature of signatures) - document.cookie = `haketilo-${signature}=; Max-Age=-1;`; - } else { - const scheme = /^([^:]*)/.exec(document.URL)[1]; - const known_scheme = ["file", "ftp"].includes(scheme); - - if (!known_scheme) - console.warn(`Unknown url scheme: \`${scheme}'!`); - - let original_url; - [policy, original_url] = extract_url_policy(document.URL, min_time); - history.replaceState(null, "", original_url); - - if (known_scheme && !policy) - policy_received_callback = employ_nonhttp_policy; +/* + * Trying to use servce workers APIs might result in exceptions, for example + * when in a non-HTML document. Because of this, we wrap the function that does + * the actual work in a try {} block. + */ +async function disable_service_workers() +{ + try { + await _disable_service_workers() + } catch (e) { + console.debug("Exception thrown during an attempt to detect and disable service workers.", e); } +} - if (!policy) { - console.debug("Using fallback policy!"); - policy = {allow: false, nonce: gen_nonce()}; +function synchronously_get_policy(url) +{ + const encoded_url = encodeURIComponent(url); + const request_url = `${browser.runtime.getURL("dummy")}?url=${encoded_url}`; + + try { + var xhttp = new XMLHttpRequest(); + xhttp.open("GET", request_url, false); + xhttp.send(); + } catch(e) { + console.error("Failure to synchronously fetch policy for url.", e); + return {allow: false}; } + const policy = /^[^?]*\?settings=(.*)$/.exec(xhttp.responseURL)[1]; + return JSON.parse(decodeURIComponent(policy)); +} + +if (!is_privileged_url(document.URL)) { + const policy = synchronously_get_policy(document.URL); + if (!(document instanceof HTMLDocument)) - policy.has_payload = false; + delete policy.payload; console.debug("current policy", policy); + report_settings(policy); + + policy.nonce = gen_nonce(); + const doc_ready = Promise.all([ policy.allow ? Promise.resolve() : sanitize_document(document, policy), policy.allow ? Promise.resolve() : disable_service_workers(), wait_loaded(document) ]); - handle_page_actions(policy.nonce, policy_received_callback, doc_ready); + handle_page_actions(policy, doc_ready); start_activity_info_server(); } diff --git a/content/page_actions.js b/content/page_actions.js index db7c352..845e452 100644 --- a/content/page_actions.js +++ b/content/page_actions.js @@ -12,19 +12,17 @@ * IMPORT CONNECTION_TYPE * IMPORT browser * IMPORT report_script - * IMPORT report_settings * IMPORT report_document_type * IMPORTS_END */ -let policy_received_callback; +let policy; /* Snapshot url and content type early; these can be changed by other code. */ let url; let is_html; let port; let loaded = false; let scripts_awaiting = []; -let nonce; function handle_message(message) { @@ -38,9 +36,8 @@ function handle_message(message) scripts_awaiting.push(script_text); } } - if (action === "settings") { - report_settings(data); - policy_received_callback({url, allow: data[1].allow}); + else { + console.error(`Bad page action '${action}'.`); } } @@ -61,27 +58,27 @@ function add_script(script_text) let script = document.createElement("script"); script.textContent = script_text; - script.setAttribute("nonce", nonce); + script.setAttribute("nonce", policy.nonce); script.haketilo_payload = true; document.body.appendChild(script); report_script(script_text); } -function handle_page_actions(script_nonce, policy_received_cb, - doc_ready_promise) { - policy_received_callback = policy_received_cb; +function handle_page_actions(_policy, doc_ready_promise) { + policy = _policy; + url = document.URL; is_html = document instanceof HTMLDocument; report_document_type(is_html); doc_ready_promise.then(document_ready); - port = browser.runtime.connect({name : CONNECTION_TYPE.PAGE_ACTIONS}); - port.onMessage.addListener(handle_message); - port.postMessage({url}); - - nonce = script_nonce; + if (policy.payload) { + port = browser.runtime.connect({name : CONNECTION_TYPE.PAGE_ACTIONS}); + port.onMessage.addListener(handle_message); + port.postMessage({payload: policy.payload}); + } } /* -- cgit v1.2.3