LocalCDN-Firefox-Chrome-Brave/core/manipulate-dom.js

173 lines
6.1 KiB
JavaScript

/**
* Remove integrity checks from embedded CSS and JavaScript files
* Belongs to LocalCDN.
*
* @author nobody
* @since 2020-02-27
*
* @license MPL 2.0
*
* 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';
/**
* Manipulate DOM
*/
var manipulateDOM = {};
/**
* Private Methods
*/
manipulateDOM._removeCrossOriginAndIntegrityAttr = function (details) {
if (details.statusCode === 200) {
let initiatorDomain, header;
initiatorDomain = helpers.extractDomainFromUrl(details.url, true) || Address.EXAMPLE;
// by Jaap (https://gitlab.com/Jaaap)
header = details.responseHeaders.find((h) => h.name.toLowerCase() === 'content-type');
if (header && manipulateDOM.checkHtmlFilterEnabled(initiatorDomain)) {
let mimeType, isAllowlisted;
mimeType = header.value.replace(/;.*/, '').toLowerCase();
isAllowlisted = stateManager._domainIsListed(initiatorDomain);
if (!isAllowlisted && mimeType === 'text/html') {
let asciiDecoder, decoder, encoder, charset, isFirstData, filter, data;
charset = (/charset\s*=/).test(header.value) && header.value.replace(/^.*?charset\s*=\s*/, '').replace(/["']?/g, '');
// Check if charset is supported by TextDecoder()
if ((/charset\s*=/).test(header.value) && !EncodingTypes[charset.toString().toLowerCase()]) {
console.error(`[ LocalCDN ] Unsupported charset: ${charset}`);
log.append(details.url, '-', `Unsupported charset: ${charset}`, true);
return;
}
asciiDecoder = new TextDecoder('ASCII');
encoder = new TextEncoder();
isFirstData = true;
filter = browser.webRequest.filterResponseData(details.requestId);
data = [];
header.value = 'text/html; charset=UTF-8';
// NOTE: should work if 'script' string is divided into two chunks
filter.ondata = (evt) => {
if (isFirstData) {
if (!charset) {
// content-type has no charset declared
let htmlHead, charsetMatch;
htmlHead = asciiDecoder.decode(evt.data, {'stream': false});
// eslint-disable-next-line no-useless-escape
charsetMatch = htmlHead.match(/<meta\s+charset=["']?([^>"'\/]+)["'>\/]/i);
if (charsetMatch === null) {
// eslint-disable-next-line no-useless-escape
charsetMatch = htmlHead.match(/<meta.*charset=["']?([^>"'\/]+)["'].*[>\/]/i) || 'utf8';
}
if (EncodingTypes[charsetMatch[1].toLowerCase().trim()] !== undefined) {
charset = charsetMatch[1].trim();
} else {
// If charset is unclear, then use ASCII by default.
// Other charsets are mostly tagged in the header or HTML source code.
// https://codeberg.org/nobody/LocalCDN/issues/567
charset = 'ASCII';
}
}
decoder = new TextDecoder(charset);
}
isFirstData = false;
data.push(evt.data);
};
filter.onstop = () => {
let str = '';
for (let buffer of data) {
str += decoder.decode(buffer, {'stream': true});
}
str += decoder.decode(); // end-of-stream
// set UTF-8 in document
str = manipulateDOM._searchCharset(str, charset);
// remove crossorigin and integrity attributes
str = str.replace(/<(link|script)[^>]+>/ig, (m) => {
// eslint-disable-next-line no-use-before-define
if (cdnDomainsRE.test(m)) {
return m.replace(/\s+(integrity|crossorigin)(="[^"]*"|='[^']*'|=[^"'`=>\s]+=?|)/ig, '');
}
return m;
});
filter.write(encoder.encode(str));
filter.close();
};
}
return {'responseHeaders': details.responseHeaders};
}
}
};
manipulateDOM._searchCharset = function (str, charset) {
if (str.indexOf(`charset="${charset}"`) > 0) {
return str.replace(`charset="${charset}"`, 'charset="utf8"');
}
if (str.indexOf(`charset='${charset}'`) > 0) {
return str.replace(`charset='${charset}'`, 'charset=\'utf8\'');
}
if (str.indexOf(`charset=${charset}`) > 0) {
return str.replace(`charset=${charset}`, 'charset=utf8');
}
return str;
};
/**
* Public Methods
*/
manipulateDOM.checkHtmlFilterEnabled = function (url) {
let listedToManipulateDOM, negateHtmlFilter;
listedToManipulateDOM = stateManager._domainIsListed(url, 'manipulate-dom');
negateHtmlFilter = stateManager.getInvertOption;
if ((negateHtmlFilter || listedToManipulateDOM) && !(negateHtmlFilter && listedToManipulateDOM)) {
return true;
}
return false;
};
/**
* Initializations
*/
/* eslint-disable one-var */
let cdnDomainsRE = new RegExp(`//(${Object.keys(mappings.cdn).map((m) => m.replace(/\W/g, '\\$&')).join('|')})/`);
/* eslint-enable one-var */
/**
* Event Handlers
*/
browser.webRequest.onHeadersReceived.addListener(
manipulateDOM._removeCrossOriginAndIntegrityAttr,
{'types': [WebRequestType.MAIN_FRAME, WebRequestType.SUB_FRAME], 'urls': [Address.ANY]},
[WebRequest.BLOCKING, WebRequest.RESPONSE_HEADERS]
);