reverselookup-worker.js (11973B) - View raw
/******************************************************************************* 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 */ /******************************************************************************/ 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, title: entry.title, supportURL: entry.supportURL, reason: entry.reason, }); 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 url = new URL(details.url || 'about:blank'); const { hostname, pathname } = url; // 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 = (details.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 hostnameTargetMatchesHostname = target => { if ( target === '' ) { return true; } if ( reHostname.test(target) ) { return true; } if ( reEntity === undefined ) { return false; } if ( reEntity.test(target) ) { return true; } return false; }; const regexTargetMatchesHostname = target => { return (new RegExp(target)).test(hostname); }; const regexTargetMatchesURL = target => { const pathPos = target.indexOf('\\/'); if ( pathPos === -1 ) { return regexTargetMatchesHostname(target); } return regexTargetMatchesHostname(`${target.slice(1, pathPos)}$`) && (new RegExp(`^${target.slice(pathPos, -1)}`)).test(pathname); }; const pathTargetMatchesURL = target => { const pathPos = target.indexOf('/'); return hostnameTargetMatchesHostname(target.slice(0, pathPos)) && pathname.startsWith(target.slice(pathPos)); }; const targetMatchesURL = target => { if ( target.charCodeAt(0) === 0x2F /* / */ ) { return regexTargetMatchesURL(target.slice(1, -1)); } if ( target.includes('/') ) { return pathTargetMatchesURL(target); } return hostnameTargetMatchesHostname(target); }; 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 /* fallthrough */ case 64: { if ( exception !== (fargs[2].charCodeAt(0) === 0x2D /* - */) ) { break; } const candidate = fargs[2].slice(1); if ( /^responseheader\(.+\)$/.test(selector) ) { if ( candidate !== needle ) { break; } if ( targetMatchesURL(fargs[1]) === false ) { break; } found = fargs[1] + prefix + selector; break; } const isProcedural = candidate.charCodeAt(0) === 0x7B /* { */; if ( isProcedural === false && candidate !== selector || isProcedural && JSON.parse(candidate).raw !== selector ) { break; } if ( targetMatchesURL(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].charCodeAt(0) === 0x2D /* - */) ) { break; } const candidate = fargs[2].slice(1); if ( candidate !== details.needle ) { break; } if (targetMatchesURL(fargs[1]) ) { found = fargs[1] + prefix + selector; } break; } default: 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; } }; /******************************************************************************/