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diff --git a/src/js/reverselookup-worker.js b/src/js/reverselookup-worker.js
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+/*******************************************************************************
+
+ uBlock Origin - a comprehensive, efficient content blocker
+ Copyright (C) 2015-present Raymond Hill
+
+ 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.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see {http://www.gnu.org/licenses/}.
+
+ Home: https://github.com/gorhill/uBlock
+*/
+
+'use strict';
+
+/******************************************************************************/
+
+let listEntries = Object.create(null);
+
+/******************************************************************************/
+
+// https://github.com/uBlockOrigin/uBlock-issues/issues/2092
+// Order of ids matters
+
+const extractBlocks = function(content, ...ids) {
+ const out = [];
+ for ( const id of ids ) {
+ const pattern = `#block-start-${id}\n`;
+ let beg = content.indexOf(pattern);
+ if ( beg === -1 ) { continue; }
+ beg += pattern.length;
+ const end = content.indexOf(`#block-end-${id}`, beg);
+ out.push(content.slice(beg, end));
+ }
+ return out.join('\n');
+};
+
+/******************************************************************************/
+
+// https://github.com/MajkiIT/polish-ads-filter/issues/14768#issuecomment-536006312
+// Avoid reporting badfilter-ed filters.
+
+const fromNetFilter = function(details) {
+ const lists = [];
+ const compiledFilter = details.compiledFilter;
+
+ for ( const assetKey in listEntries ) {
+ const entry = listEntries[assetKey];
+ if ( entry === undefined ) { continue; }
+ if ( entry.networkContent === undefined ) {
+ entry.networkContent = extractBlocks(entry.content, 'NETWORK_FILTERS:GOOD');
+ }
+ const content = entry.networkContent;
+ let pos = 0;
+ for (;;) {
+ pos = content.indexOf(compiledFilter, pos);
+ if ( pos === -1 ) { break; }
+ // We need an exact match.
+ // https://github.com/gorhill/uBlock/issues/1392
+ // https://github.com/gorhill/uBlock/issues/835
+ const notFound = pos !== 0 && content.charCodeAt(pos - 1) !== 0x0A;
+ pos += compiledFilter.length;
+ if (
+ notFound ||
+ pos !== content.length && content.charCodeAt(pos) !== 0x0A
+ ) {
+ continue;
+ }
+ lists.push({
+ assetKey: assetKey,
+ title: entry.title,
+ supportURL: entry.supportURL
+ });
+ break;
+ }
+ }
+
+ const response = {};
+ response[details.rawFilter] = lists;
+
+ self.postMessage({ id: details.id, response });
+};
+
+/******************************************************************************/
+
+// Looking up filter lists from a cosmetic filter is a bit more complicated
+// than with network filters:
+//
+// The filter is its raw representation, not its compiled version. This is
+// because the cosmetic filtering engine can't translate a live cosmetic
+// filter into its compiled version. Reason is I do not want to burden
+// cosmetic filtering with the resource overhead of being able to recompile
+// live cosmetic filters. I want the cosmetic filtering code to be left
+// completely unaffected by reverse lookup requirements.
+//
+// Mainly, given a CSS selector and a hostname as context, we will derive
+// various versions of compiled filters and see if there are matches. This
+// way the whole CPU cost is incurred by the reverse lookup code -- in a
+// worker thread, and the cosmetic filtering engine incurs no cost at all.
+//
+// For this though, the reverse lookup code here needs some knowledge of
+// the inners of the cosmetic filtering engine.
+// FilterContainer.fromCompiledContent() is our reference code to create
+// the various compiled versions.
+
+const fromExtendedFilter = function(details) {
+ const match = /^#@?#\^?/.exec(details.rawFilter);
+ const prefix = match[0];
+ const exception = prefix.charAt(1) === '@';
+ const selector = details.rawFilter.slice(prefix.length);
+ const isHtmlFilter = prefix.endsWith('^');
+ const hostname = details.hostname;
+
+ // The longer the needle, the lower the number of false positives.
+ // https://github.com/uBlockOrigin/uBlock-issues/issues/1139
+ // Mind that there is no guarantee a selector has `\w` characters.
+ const needle = selector.match(/\w+|\*/g).reduce(function(a, b) {
+ return a.length > b.length ? a : b;
+ });
+
+ const regexFromLabels = (prefix, hn, suffix) =>
+ new RegExp(
+ prefix +
+ hn.split('.').reduce((acc, item) => `(${acc}\\.)?${item}`) +
+ suffix
+ );
+
+ // https://github.com/uBlockOrigin/uBlock-issues/issues/803
+ // Support looking up selectors of the form `*##...`
+ const reHostname = regexFromLabels('^', hostname, '$');
+ let reEntity;
+ {
+ const domain = details.domain;
+ const pos = domain.indexOf('.');
+ if ( pos !== -1 ) {
+ reEntity = regexFromLabels(
+ '^(',
+ hostname.slice(0, pos + hostname.length - domain.length),
+ '\\.)?\\*$'
+ );
+ }
+ }
+
+ const hostnameMatches = hn => {
+ if ( hn === '' ) { return true; }
+ if ( hn.charCodeAt(0) === 0x2F /* / */ ) {
+ return (new RegExp(hn.slice(1,-1))).test(hostname);
+ }
+ if ( reHostname.test(hn) ) { return true; }
+ if ( reEntity === undefined ) { return false; }
+ if ( reEntity.test(hn) ) { return true; }
+ return false;
+ };
+
+ const response = Object.create(null);
+
+ for ( const assetKey in listEntries ) {
+ const entry = listEntries[assetKey];
+ if ( entry === undefined ) { continue; }
+ if ( entry.extendedContent === undefined ) {
+ entry.extendedContent = extractBlocks(
+ entry.content,
+ 'COSMETIC_FILTERS:SPECIFIC',
+ 'COSMETIC_FILTERS:GENERIC',
+ 'SCRIPTLET_FILTERS',
+ 'HTML_FILTERS',
+ 'HTTPHEADER_FILTERS'
+ );
+ }
+ const content = entry.extendedContent;
+ let found;
+ let pos = 0;
+ while ( (pos = content.indexOf(needle, pos)) !== -1 ) {
+ let beg = content.lastIndexOf('\n', pos);
+ if ( beg === -1 ) { beg = 0; }
+ let end = content.indexOf('\n', pos);
+ if ( end === -1 ) { end = content.length; }
+ pos = end;
+ const fargs = JSON.parse(content.slice(beg, end));
+ const filterType = fargs[0];
+
+ // https://github.com/gorhill/uBlock/issues/2763
+ if ( filterType === 0 && details.ignoreGeneric ) { continue; }
+
+ // Do not confuse cosmetic filters with HTML ones.
+ if ( (filterType === 64) !== isHtmlFilter ) { continue; }
+
+ switch ( filterType ) {
+ // Lowly generic cosmetic filters
+ case 0:
+ if ( exception ) { break; }
+ if ( fargs[2] !== selector ) { break; }
+ found = prefix + selector;
+ break;
+ // Highly generic cosmetic filters
+ case 4: // simple highly generic
+ case 5: // complex highly generic
+ if ( exception ) { break; }
+ if ( fargs[1] !== selector ) { break; }
+ found = prefix + selector;
+ break;
+ // Specific cosmetic filtering
+ // Generic exception
+ case 8:
+ // HTML filtering
+ // Response header filtering
+ case 64: {
+ if ( exception !== ((fargs[2] & 0b001) !== 0) ) { break; }
+ const isProcedural = (fargs[2] & 0b010) !== 0;
+ if (
+ isProcedural === false && fargs[3] !== selector ||
+ isProcedural && JSON.parse(fargs[3]).raw !== selector
+ ) {
+ break;
+ }
+ if ( hostnameMatches(fargs[1]) === false ) { break; }
+ // https://www.reddit.com/r/uBlockOrigin/comments/d6vxzj/
+ // Ignore match if specific cosmetic filters are disabled
+ if (
+ filterType === 8 &&
+ exception === false &&
+ details.ignoreSpecific
+ ) {
+ break;
+ }
+ found = fargs[1] + prefix + selector;
+ break;
+ }
+ // Scriptlet injection
+ case 32:
+ if ( exception !== ((fargs[2] & 0b001) !== 0) ) { break; }
+ if ( fargs[3] !== details.compiled ) { break; }
+ if ( hostnameMatches(fargs[1]) ) {
+ found = fargs[1] + prefix + selector;
+ }
+ break;
+ }
+ if ( found !== undefined ) {
+ if ( response[found] === undefined ) {
+ response[found] = [];
+ }
+ response[found].push({
+ assetKey: assetKey,
+ title: entry.title,
+ supportURL: entry.supportURL
+ });
+ break;
+ }
+ }
+ }
+
+ self.postMessage({ id: details.id, response });
+};
+
+/******************************************************************************/
+
+self.onmessage = function(e) {
+ const msg = e.data;
+
+ switch ( msg.what ) {
+ case 'resetLists':
+ listEntries = Object.create(null);
+ break;
+
+ case 'setList':
+ listEntries[msg.details.assetKey] = msg.details;
+ break;
+
+ case 'fromNetFilter':
+ fromNetFilter(msg);
+ break;
+
+ case 'fromExtendedFilter':
+ fromExtendedFilter(msg);
+ break;
+ }
+};
+
+/******************************************************************************/
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-02 10:54:42 +0000