From b1228f9d513c1791d776c926f63da2e6ea8aee6f Mon Sep 17 00:00:00 2001 From: Raymond Hill Date: Sat, 13 Mar 2021 09:38:29 -0500 Subject: [PATCH] Add missing new JS file Related issue: - https://github.com/uBlockOrigin/uBlock-issues/issues/1527#issuecomment-798449462 Related commit: - https://github.com/gorhill/uBlock/commit/f876b68171ff307f27601225607a6801f400437d --- src/js/httpheader-filtering.js | 228 +++++++++++++++++++++++++++++++++ 1 file changed, 228 insertions(+) create mode 100644 src/js/httpheader-filtering.js diff --git a/src/js/httpheader-filtering.js b/src/js/httpheader-filtering.js new file mode 100644 index 000000000..52e78721a --- /dev/null +++ b/src/js/httpheader-filtering.js @@ -0,0 +1,228 @@ +/******************************************************************************* + + uBlock Origin - a browser extension to block requests. + Copyright (C) 2021-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'; + +/******************************************************************************/ + +{ +// >>>>> start of local scope + +/******************************************************************************/ + +const µb = µBlock; +const duplicates = new Set(); +const filterDB = new µb.staticExtFilteringEngine.HostnameBasedDB(1); +const sessionFilterDB = new µb.staticExtFilteringEngine.SessionDB(); + +const $headers = new Set(); +const $exceptions = new Set(); + +let acceptedCount = 0; +let discardedCount = 0; + +const headerIndexFromName = function(name, headers) { + let i = headers.length; + while ( i-- ) { + if ( headers[i].name.toLowerCase() === name ) { + return i; + } + } + return -1; +}; + +const logOne = function(isException, token, fctxt) { + fctxt.duplicate() + .setRealm('extended') + .setType('header') + .setFilter({ + modifier: true, + result: isException ? 2 : 1, + source: 'extended', + raw: `${(isException ? '#@#' : '##')}^responseheader(${token})` + }) + .toLogger(); +}; + +const api = { + get acceptedCount() { + return acceptedCount; + }, + get discardedCount() { + return discardedCount; + } +}; + +api.reset = function() { + filterDB.clear(); + duplicates.clear(); + acceptedCount = 0; + discardedCount = 0; +}; + +api.freeze = function() { + duplicates.clear(); + filterDB.collectGarbage(); +}; + +api.compile = function(parser, writer) { + writer.select(µb.compiledHTTPHeaderSection); + + const { compiled, exception } = parser.result; + const headerName = compiled.slice(15, -1); + + // Tokenless is meaningful only for exception filters. + if ( headerName === '' && exception === false ) { return; } + + // Only exception filters are allowed to be global. + if ( parser.hasOptions() === false ) { + if ( exception ) { + writer.push([ 64, '', 1, compiled ]); + } + return; + } + + // https://github.com/gorhill/uBlock/issues/3375 + // Ignore instances of exception filter with negated hostnames, + // because there is no way to create an exception to an exception. + + for ( const { hn, not, bad } of parser.extOptions() ) { + if ( bad ) { continue; } + let kind = 0; + if ( exception ) { + if ( not ) { continue; } + kind |= 1; + } else if ( not ) { + kind |= 1; + } + writer.push([ 64, hn, kind, compiled ]); + } +}; + +api.compileTemporary = function(parser) { + return { + session: sessionFilterDB, + selector: parser.result.compiled.slice(15, -1), + }; +}; + +// 01234567890123456789 +// responseheader(name) +// ^ ^ +// 15 -1 + +api.fromCompiledContent = function(reader) { + reader.select(µb.compiledHTTPHeaderSection); + + while ( reader.next() ) { + acceptedCount += 1; + const fingerprint = reader.fingerprint(); + if ( duplicates.has(fingerprint) ) { + discardedCount += 1; + continue; + } + duplicates.add(fingerprint); + const args = reader.args(); + if ( args.length < 4 ) { continue; } + filterDB.store(args[1], args[2], args[3].slice(15, -1)); + } +}; + +api.getSession = function() { + return sessionFilterDB; +}; + +api.apply = function(fctxt, headers) { + if ( filterDB.size === 0 ) { return; } + + const hostname = fctxt.getHostname(); + if ( hostname === '' ) { return; } + + const domain = fctxt.getDomain(); + let entity = µb.URI.entityFromDomain(domain); + if ( entity !== '' ) { + entity = `${hostname.slice(0, -domain.length)}${entity}`; + } else { + entity = '*'; + } + + $headers.clear(); + $exceptions.clear(); + + if ( sessionFilterDB.isNotEmpty ) { + sessionFilterDB.retrieve([ null, $exceptions ]); + } + filterDB.retrieve(hostname, [ $headers, $exceptions ]); + filterDB.retrieve(entity, [ $headers, $exceptions ], 1); + if ( $headers.size === 0 ) { return; } + + // https://github.com/gorhill/uBlock/issues/2835 + // Do not filter response headers if the site is under an `allow` rule. + if ( + µb.userSettings.advancedUserEnabled && + µb.sessionFirewall.evaluateCellZY(hostname, hostname, '*') === 2 + ) { + return; + } + + const hasGlobalException = $exceptions.has(''); + const loggerEnabled = µb.logger.enabled; + + let modified = false; + + for ( const name of $headers ) { + for (;;) { + const i = headerIndexFromName(name, headers); + if ( i === -1 ) { break; } + const isExcepted = hasGlobalException || $exceptions.has(name); + if ( isExcepted ) { + if ( loggerEnabled ) { + logOne(true, hasGlobalException ? '' : name, fctxt); + } + break; + } + headers.splice(i, 1); + if ( loggerEnabled ) { + logOne(false, name, fctxt); + } + modified = true; + } + } + + return modified; +}; + +api.toSelfie = function() { + return filterDB.toSelfie(); +}; + +api.fromSelfie = function(selfie) { + filterDB.fromSelfie(selfie); +}; + +µb.httpheaderFilteringEngine = api; + +/******************************************************************************/ + +// <<<<< end of local scope +} + +/******************************************************************************/