/******************************************************************************* µMatrix - a Chromium browser extension to black/white list requests. Copyright (C) 2014 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/uMatrix */ /* global chrome, µMatrix */ /******************************************************************************/ // Start isolation from global scope µMatrix.webRequest = (function() { /******************************************************************************/ // The `id='uMatrix'` is important, it allows µMatrix to detect whether a // specific data URI originates from itself. var rootFrameReplacement = [ '', '', '', '', 'Blocked by µMatrix', '', '', '
', '
{{hostname}} blocked by HTTP Switchboard
', '
', 'hpHosts: {{hostname}}
', 'WOT: {{hostname}}', '
', '
', '', '' ].join(''); var subFrameReplacement = [ '', '', '', '', 'Blocked by µMatrix', '', '', '
{{hostname}}
', '', '' ].join(''); /******************************************************************************/ // If it is HTTP Switchboard's root frame replacement URL, verify that // the page that was blacklisted is still blacklisted, and if not, // redirect to the previously blacklisted page. var onBeforeChromeExtensionRequestHandler = function(details) { var requestURL = details.url; // console.debug('onBeforeChromeExtensionRequestHandler()> "%s": %o', details.url, details); // rhill 2013-12-10: Avoid regex whenever a faster indexOf() can be used: // here we can use fast indexOf() as a first filter -- which is executed // for every single request (so speed matters). var matches = requestURL.match(/url=([^&]+)&hostname=([^&]+)/); if ( !matches ) { return; } // Is the target page still blacklisted? var pageURL = decodeURIComponent(matches[1]); var hostname = decodeURIComponent(matches[2]); if ( µMatrix.mustBlock(this.scopeFromURL(pageURL), hostname, '*') ) { return; } µMatrix.asyncJobs.add( 'gotoURL-' + details.tabId, { tabId: details.tabId, url: pageURL }, µMatrix.utils.gotoURL, 200, false ); }; /******************************************************************************/ // Intercept and filter web requests according to white and black lists. var onBeforeRootFrameRequestHandler = function(details) { var µm = µMatrix; // Do not ignore traffic outside tabs var tabId = details.tabId; if ( tabId < 0 ) { tabId = µm.behindTheSceneTabId; } // It's a root frame, bind to a new page stats store else { µm.bindTabToPageStats(tabId, details.url); } var uri = µm.URI.set(details.url); if ( uri.scheme !== 'http' && uri.scheme !== 'https' ) { return; } var requestURL = uri.normalizedURI(); var requestHostname = uri.hostname; var pageStats = µm.pageStatsFromTabId(tabId); var pageURL = µm.pageUrlFromPageStats(pageStats); var block = µm.evaluateURL(pageURL, requestHostname, '*') === µm.Matrix.RedDirect; // console.debug('onBeforeRequestHandler()> block=%s "%s": %o', block, details.url, details); // whitelisted? if ( !block ) { // rhill 2013-11-07: Senseless to do this for behind-the-scene requests. // rhill 2013-12-03: Do this here only for root frames. if ( tabId !== µm.behindTheSceneTabId ) { µm.cookieHunter.recordPageCookies(pageStats); } // quickProfiler.stop(); return; } // blacklisted // rhill 2014-01-15: Delay logging of non-blocked top `main_frame` // requests, in order to ensure any potential redirects is reported // in proper chronological order. // https://github.com/gorhill/httpswitchboard/issues/112 pageStats.recordRequest('doc', requestURL, block); // If it's a blacklisted frame, redirect to frame.html // rhill 2013-11-05: The root frame contains a link to noop.css, this // allows to later check whether the root frame has been unblocked by the // user, in which case we are able to force a reload using a redirect. var html = rootFrameReplacement; html = html.replace('{{cssURL}}', µm.noopCSSURL); html = html.replace(/{{hostname}}/g, encodeURIComponent(requestHostname)); html = html.replace('{{originalURL}}', encodeURIComponent(requestURL)); html = html.replace('{{now}}', String(Date.now())); var dataURI = 'data:text/html;base64,' + btoa(html); // quickProfiler.stop(); return { 'redirectUrl': dataURI }; }; /******************************************************************************/ // Process a request. // // This can be called from the context of onBeforeSendRequest() or // onBeforeSendHeaders(). var processRequest = function(µm, details) { var µmuri = µm.URI; var requestType = requestTypeNormalizer[details.type]; var requestURL = µmuri.set(details.url).normalizedURI(); var requestHostname = µmuri.hostname; var requestPath = µmuri.path; // Re-classify orphan HTTP requests as behind-the-scene requests. There is // not much else which can be done, because there are URLs // which cannot be handled by HTTP Switchboard, i.e. `opera://startpage`, // as this would lead to complications with no obvious solution, like how // to scope on unknown scheme? Etc. // https://github.com/gorhill/httpswitchboard/issues/191 // https://github.com/gorhill/httpswitchboard/issues/91#issuecomment-37180275 var pageStats = µm.pageStatsFromTabId(details.tabId); if ( !pageStats ) { pageStats = µm.pageStatsFromTabId(µm.behindTheSceneTabId); } var pageURL = µm.pageUrlFromPageStats(pageStats); // rhill 2013-12-15: // Try to transpose generic `other` category into something more // meaningful. if ( requestType === 'other' ) { requestType = µm.transposeType(requestType, requestPath); } // Block request? var block = µm.mustBlock(µm.scopeFromURL(pageURL), requestHostname, requestType); var reason; // Record request. // https://github.com/gorhill/httpswitchboard/issues/342 // The way requests are handled now, it may happen at this point some // processing has already been performed, and that a synthetic URL has // been constructed for logging purpose. Use this synthetic URL if // it is available. pageStats.recordRequest(requestType, details.µmRequestURL || requestURL, block, false); // whitelisted? if ( !block ) { // console.debug('onBeforeRequestHandler()> ALLOW "%s": %o', details.url, details); return; } // blacklisted // console.debug('onBeforeRequestHandler()> BLOCK "%s": %o', details.url, details); // If it's a blacklisted frame, redirect to frame.html // rhill 2013-11-05: The root frame contains a link to noop.css, this // allows to later check whether the root frame has been unblocked by the // user, in which case we are able to force a reload using a redirect. if ( requestType === 'frame' ) { var html = subFrameReplacement .replace(/{{hostname}}/g, requestHostname) .replace('{{frameSrc}}', requestURL) .replace(/{{subframeColor}}/g, µm.userSettings.subframeColor) .replace('{{subframeOpacity}}', (µm.userSettings.subframeOpacity / 100).toFixed(1)); return { 'redirectUrl': 'data:text/html,' + encodeURIComponent(html) }; } return { 'cancel': true }; }; /******************************************************************************/ // Intercept and filter web requests according to white and black lists. var onBeforeRequestHandler = function(details) { var µm = µMatrix; var µmuri = µm.URI; var requestURL = details.url; var requestScheme = µmuri.schemeFromURI(requestURL); // rhill 2014-02-17: Ignore 'filesystem:': this can happen when listening // to 'chrome-extension://'. if ( requestScheme === 'filesystem' ) { return; } // quickProfiler.start('onBeforeRequest'); // console.debug('onBeforeRequestHandler()> "%s": %o', details.url, details); var requestType = requestTypeNormalizer[details.type]; // https://github.com/gorhill/httpswitchboard/issues/303 // Wherever the main doc comes from, create a receiver page URL: synthetize // one if needed. if ( requestType === 'doc' && details.parentFrameId < 0 ) { return onBeforeRootFrameRequestHandler(details); } // Is it µMatrix's noop css file? if ( requestType === 'css' && requestURL.slice(0, µm.noopCSSURL.length) === µm.noopCSSURL ) { return onBeforeChromeExtensionRequestHandler(details); } // Ignore non-http schemes if ( requestScheme.indexOf('http') !== 0 ) { return; } // Do not block myself from updating assets // https://github.com/gorhill/httpswitchboard/issues/202 if ( requestType === 'xhr' && requestURL.slice(0, µm.projectServerRoot.length) === µm.projectServerRoot ) { return; } // https://github.com/gorhill/httpswitchboard/issues/342 // If the request cannot be bound to a specific tab, delay request // handling to onBeforeSendHeaders(), maybe there the referrer // information will allow us to properly bind the request to the tab // from which it originates. // Important: since it is not possible to redirect requests at // onBeforeSendHeaders() point, we can't delay when the request type is // `sub_frame`. if ( requestType !== 'frame' && details.tabId < 0 ) { return; } return processRequest(µm, details); }; /******************************************************************************/ // This is where tabless requests are processed, as here there may be a chance // we can bind a request to a specific tab, as headers may contain useful // information to accomplish this. // // Also we sanitize outgoing headers as per user settings. var onBeforeSendHeadersHandler = function(details) { var µm = µMatrix; var requestURL = details.url; // console.debug('onBeforeSendHeadersHandler()> "%s": %o', details.url, details); // Do not block myself from updating assets // https://github.com/gorhill/httpswitchboard/issues/202 var requestType = requestTypeNormalizer[details.type]; if ( requestType === 'xhr' && requestURL.slice(0, µm.projectServerRoot.length) === µm.projectServerRoot ) { return; } // https://github.com/gorhill/httpswitchboard/issues/342 // Is this hyperlink auditing? // If yes, create a synthetic URL for reporting hyperlink auditing // record requests. This way the user is better informed of what went // on. var linkAuditor = hyperlinkAuditorFromHeaders(details.requestHeaders); if ( linkAuditor ) { details.µmRequestURL = requestURL + '{Ping-To:' + linkAuditor + '}'; } // If we are dealing with a behind-the-scene request, make a last attempt // to bind the request to a specific tab by using the referrer or the // `Ping-From` header if any of these exists. var r; if ( details.tabId < 0 ) { details.tabId = tabIdFromHeaders(µm, details.requestHeaders) || -1; // Do not process `main_frame`/`sub_frame` requests, these were handled // unconditionally at onBeforeRequest() time (because of potential // need to redirect). if ( requestType !== 'doc' && requestType !== 'frame' ) { r = processRequest(µm, details); } } // If the request was not cancelled above, check whether hyperlink auditing // is globally forbidden. if ( !r ) { if ( linkAuditor && µm.userSettings.processHyperlinkAuditing ) { r = { 'cancel': true }; } } // Block request? if ( r ) { // Count number of hyperlink auditing foiled, even attempts blocked // through the matrix. if ( linkAuditor ) { µm.hyperlinkAuditingFoiledCounter += 1; } return r; } // If we reach this point, request is not blocked, so what is left to do // is to sanitize headers. // Re-classify orphan HTTP requests as behind-the-scene requests. There is // not much else which can be done, because there are URLs // which cannot be handled by HTTP Switchboard, i.e. `opera://startpage`, // as this would lead to complications with no obvious solution, like how // to scope on unknown scheme? Etc. // https://github.com/gorhill/httpswitchboard/issues/191 // https://github.com/gorhill/httpswitchboard/issues/91#issuecomment-37180275 var tabId = details.tabId; var pageStats = µm.pageStatsFromTabId(tabId); if ( !pageStats ) { tabId = µm.behindTheSceneTabId; pageStats = µm.pageStatsFromTabId(tabId); } var pageURL = µm.pageUrlFromPageStats(pageStats); var reqHostname = µm.hostnameFromURL(requestURL); var changed = false; if ( µm.mustBlock(µm.scopeFromURL(pageURL), reqHostname, 'cookie') ) { changed = foilCookieHeaders(µm, details) || changed; } // TODO: use cookie cell to determine whether the referrer info must be // foiled. if ( µm.userSettings.processReferer && µm.mustBlock(this.scopeFromURL(pageURL), reqHostname, '*') ) { changed = foilRefererHeaders(µm, reqHostname, details) || changed; } if ( µm.userSettings.spoofUserAgent ) { changed = foilUserAgent(µm, details) || changed; // https://github.com/gorhill/httpswitchboard/issues/252 // To avoid potential mismatch between the user agent from HTTP headers // and the user agent from subrequests and the window.navigator object, // I could always store here the effective user agent, but I am really // not convinced it is worth the added overhead given the low // probability and the benign consequence if it ever happen. Can always // be revised if ever I become aware a mismatch is a terrible thing } if ( changed ) { // console.debug('onBeforeSendHeadersHandler()> CHANGED "%s": %o', requestURL, details); return { requestHeaders: details.requestHeaders }; } }; /******************************************************************************/ // http://www.whatwg.org/specs/web-apps/current-work/multipage/links.html#hyperlink-auditing // // Target URL = the href of the link // Doc URL = URL of the document containing the target URL // Ping URLs = servers which will be told that user clicked target URL // // `Content-Type` = `text/ping` (always present) // `Ping-To` = target URL (always present) // `Ping-From` = doc URL // `Referer` = doc URL // request URL = URL which will receive the information // // With hyperlink-auditing, removing header(s) is pointless, the whole // request must be cancelled. var hyperlinkAuditorFromHeaders = function(headers) { var i = headers.length; while ( i-- ) { if ( headers[i].name.toLowerCase() === 'ping-to' ) { return headers[i].value; } } return; }; /******************************************************************************/ var tabIdFromHeaders = function(µm, headers) { var header; var i = headers.length; while ( i-- ) { header = headers[i]; if ( header.name.toLowerCase() === 'referer' ) { return µm.tabIdFromPageUrl(header.value); } if ( header.name.toLowerCase() === 'ping-from' ) { return µm.tabIdFromPageUrl(header.value); } } return -1; }; /******************************************************************************/ var foilCookieHeaders = function(µm, details) { var changed = false; var headers = details.requestHeaders; var header; var i = headers.length; while ( i-- ) { header = headers[i]; if ( header.name.toLowerCase() !== 'cookie' ) { continue; } // console.debug('foilCookieHeaders()> foiled browser attempt to send cookie(s) to "%s"', details.url); headers.splice(i, 1); µm.cookieHeaderFoiledCounter++; changed = true; } return changed; }; /******************************************************************************/ var foilRefererHeaders = function(µm, toHostname, details) { var headers = details.requestHeaders; var header; var fromDomain, toDomain; var i = headers.length; while ( i-- ) { header = headers[i]; if ( header.name.toLowerCase() !== 'referer' ) { continue; } fromDomain = µm.URI.domainFromURI(header.value); if ( !toDomain ) { toDomain = µm.URI.domainFromHostname(toHostname); } if ( toDomain === fromDomain ) { continue; } // console.debug('foilRefererHeaders()> foiled referer "%s" for "%s"', fromDomain, toDomain); // https://github.com/gorhill/httpswitchboard/issues/222#issuecomment-44828402 // Splicing instead of blanking: not sure how much it helps headers.splice(i, 1); µm.refererHeaderFoiledCounter++; return true; } return false; }; /******************************************************************************/ var foilUserAgent = function(µm, details) { var headers = details.requestHeaders; var header; var i = 0; while ( header = headers[i] ) { if ( header.name.toLowerCase() === 'user-agent' ) { header.value = µm.userAgentReplaceStr; return true; // Assuming only one `user-agent` entry } i += 1; } return false; }; /******************************************************************************/ // To prevent inline javascript from being executed. // Prevent inline scripting using `Content-Security-Policy`: // https://dvcs.w3.org/hg/content-security-policy/raw-file/tip/csp-specification.dev.html // This fixes: // https://github.com/gorhill/httpswitchboard/issues/35 var onHeadersReceived = function(details) { // console.debug('onHeadersReceived()> "%s": %o', details.url, details); // Ignore schemes other than 'http...' if ( details.url.indexOf('http') !== 0 ) { return; } var requestType = requestTypeNormalizer[details.type]; if ( requestType === 'frame' ) { return onSubDocHeadersReceived(details); } if ( requestType === 'doc' ) { return onMainDocHeadersReceived(details); } }; /******************************************************************************/ var onMainDocHeadersReceived = function(details) { // console.debug('onMainDocHeadersReceived()> "%s": %o', details.url, details); var µm = µMatrix; // Do not ignore traffic outside tabs. // https://github.com/gorhill/httpswitchboard/issues/91#issuecomment-37180275 var tabId = details.tabId; if ( tabId < 0 ) { tabId = µm.behindTheSceneTabId; } var µmuri = µm.URI.set(details.url); var requestURL = µmuri.normalizedURI(); var requestScheme = µmuri.scheme; var requestHostname = µmuri.hostname; // rhill 2013-12-07: // Apparently in Opera, onBeforeRequest() is triggered while the // URL is not yet bound to a tab (-1), which caused the code here // to not be able to lookup the pageStats. So let the code here bind // the page to a tab if not done yet. // https://github.com/gorhill/httpswitchboard/issues/75 µm.bindTabToPageStats(tabId, requestURL); // Re-classify orphan HTTP requests as behind-the-scene requests. There is // not much else which can be done, because there are URLs // which cannot be handled by HTTP Switchboard, i.e. `opera://startpage`, // as this would lead to complications with no obvious solution, like how // to scope on unknown scheme? Etc. // https://github.com/gorhill/httpswitchboard/issues/191 // https://github.com/gorhill/httpswitchboard/issues/91#issuecomment-37180275 var pageStats = µm.pageStatsFromTabId(tabId); if ( !pageStats ) { tabId = µm.behindTheSceneTabId; pageStats = µm.pageStatsFromTabId(tabId); } var headers = details.responseHeaders; // Simplify code paths by splitting func in two different handlers, one // for main docs, one for sub docs. // rhill 2014-01-15: Report redirects. // https://github.com/gorhill/httpswitchboard/issues/112 // rhill 2014-02-10: Handle all redirects. // https://github.com/gorhill/httpswitchboard/issues/188 if ( /\s+30[12378]\s+/.test(details.statusLine) ) { var i = headerIndexFromName('location', headers); if ( i >= 0 ) { // rhill 2014-01-20: Be ready to handle relative URLs. // https://github.com/gorhill/httpswitchboard/issues/162 var locationURL = µmuri.set(headers[i].value.trim()).normalizedURI(); if ( µmuri.authority === '' ) { locationURL = requestScheme + '://' + requestHostname + µmuri.path; } µm.redirectRequests[locationURL] = requestURL; } // console.debug('onMainDocHeadersReceived()> redirect "%s" to "%s"', requestURL, headers[i].value); } // rhill 2014-01-11: Auto-scope and/or auto-whitelist only when the // `main_frame` object is really received (status = 200 OK), i.e. avoid // redirection, because the final URL might differ. This ensures proper // scope is looked-up before auto-site-scoping and/or auto-whitelisting. // https://github.com/gorhill/httpswitchboard/issues/119 if ( details.statusLine.indexOf(' 200') > 0 ) { // rhill 2014-01-15: Report redirects if any. // https://github.com/gorhill/httpswitchboard/issues/112 var mainFrameStack = [requestURL]; var destinationURL = requestURL; var sourceURL; while ( sourceURL = µm.redirectRequests[destinationURL] ) { mainFrameStack.push(sourceURL); delete µm.redirectRequests[destinationURL]; destinationURL = sourceURL; } while ( destinationURL = mainFrameStack.pop() ) { pageStats.recordRequest('doc', destinationURL, false); } // rhill 2013-12-23: Auto-whitelist page domain? if ( µm.userSettings.autoWhitelistPageDomain ) { µm.autoWhitelist1stPartyTemporarily(requestURL); } } // Evaluate if ( µm.mustAllow(µm.scopeFromURL(µm.pageUrlFromPageStats(pageStats)), requestHostname, 'script') ) { // https://github.com/gorhill/httpswitchboard/issues/181 pageStats.pageScriptBlocked = false; return; } // https://github.com/gorhill/httpswitchboard/issues/181 pageStats.pageScriptBlocked = true; // If javascript not allowed, say so through a `Content-Security-Policy` // directive. // console.debug('onMainDocHeadersReceived()> PAGE CSP "%s": %o', details.url, details); headers.push({ 'name': 'Content-Security-Policy', 'value': "script-src 'none'" }); return { responseHeaders: headers }; }; /******************************************************************************/ var onSubDocHeadersReceived = function(details) { // console.debug('onSubDocHeadersReceived()> "%s": %o', details.url, details); var µm = µMatrix; // Do not ignore traffic outside tabs. // https://github.com/gorhill/httpswitchboard/issues/91#issuecomment-37180275 var tabId = details.tabId; if ( tabId < 0 ) { tabId = µm.behindTheSceneTabId; } // Re-classify orphan HTTP requests as behind-the-scene requests. There is // not much else which can be done, because there are URLs // which cannot be handled by HTTP Switchboard, i.e. `opera://startpage`, // as this would lead to complications with no obvious solution, like how // to scope on unknown scheme? Etc. // https://github.com/gorhill/httpswitchboard/issues/191 // https://github.com/gorhill/httpswitchboard/issues/91#issuecomment-37180275 var pageStats = µm.pageStatsFromTabId(tabId); if ( !pageStats ) { tabId = µm.behindTheSceneTabId; pageStats = µm.pageStatsFromTabId(tabId); } // Evaluate if ( µm.mustAllow(µm.scopeFromURL(µm.pageUrlFromPageStats(pageStats)), µm.hostnameFromURL(details.url), 'script') ) { return; } // If javascript not allowed, say so through a `Content-Security-Policy` // directive. // For inline javascript within iframes, we need to sandbox. // https://github.com/gorhill/httpswitchboard/issues/73 // Now because sandbox cancels all permissions, this means // not just javascript is disabled. To avoid negative side // effects, I allow some other permissions, but... // TODO: Reuse CSP `sandbox` directive if it's already in the // headers (strip out `allow-scripts` if present), // and find out if the `sandbox` in the header interfere with a // `sandbox` attribute which might be present on the iframe. // console.debug('onSubDocHeadersReceived()> FRAME CSP "%s": %o, scope="%s"', details.url, details, pageURL); details.responseHeaders.push({ 'name': 'Content-Security-Policy', 'value': 'sandbox allow-forms allow-same-origin' }); return { responseHeaders: details.responseHeaders }; }; /******************************************************************************/ // As per Chrome API doc, webRequest.onErrorOccurred event is the last // one called in the sequence of webRequest events. // http://developer.chrome.com/extensions/webRequest.html var onErrorOccurredHandler = function(details) { // console.debug('onErrorOccurred()> "%s": %o', details.url, details); var requestType = requestTypeNormalizer[details.type]; // Ignore all that is not a main document if ( requestType !== 'doc'|| details.parentFrameId >= 0 ) { return; } var µm = µMatrix; var pageStats = µm.pageStatsFromPageUrl(details.url); if ( !pageStats ) { return; } // rhill 2014-01-28: Unwind the stack of redirects if any. Chromium will // emit an error when a web page redirects apparently endlessly, so // we need to unravel and report all these redirects upon error. // https://github.com/gorhill/httpswitchboard/issues/171 var requestURL = µm.URI.set(details.url).normalizedURI(); var mainFrameStack = [requestURL]; var destinationURL = requestURL; var sourceURL; while ( sourceURL = µm.redirectRequests[destinationURL] ) { mainFrameStack.push(sourceURL); delete µm.redirectRequests[destinationURL]; destinationURL = sourceURL; } while ( destinationURL = mainFrameStack.pop() ) { pageStats.recordRequest('doc', destinationURL, false); } }; /******************************************************************************/ // Caller must ensure headerName is normalized to lower case. var headerIndexFromName = function(headerName, headers) { var i = headers.length; while ( i-- ) { if ( headers[i].name.toLowerCase() === headerName ) { return i; } } return -1; }; /******************************************************************************/ var requestTypeNormalizer = { 'main_frame' : 'doc', 'sub_frame' : 'frame', 'stylesheet' : 'css', 'script' : 'script', 'image' : 'image', 'object' : 'plugin', 'xmlhttprequest': 'xhr', 'other' : 'other' }; /******************************************************************************/ chrome.webRequest.onBeforeRequest.addListener( onBeforeRequestHandler, { "urls": [ "http://*/*", "https://*/*", "chrome-extension://*/*" ], "types": [ "main_frame", "sub_frame", 'stylesheet', "script", "image", "object", "xmlhttprequest", "other" ] }, [ "blocking" ] ); console.log('HTTP Switchboard> Beginning to intercept net requests at %s', (new Date()).toISOString()); chrome.webRequest.onBeforeSendHeaders.addListener( onBeforeSendHeadersHandler, { 'urls': [ "http://*/*", "https://*/*" ] }, ['blocking', 'requestHeaders'] ); chrome.webRequest.onHeadersReceived.addListener( onHeadersReceived, { 'urls': [ "http://*/*", "https://*/*" ] }, ['blocking', 'responseHeaders'] ); chrome.webRequest.onErrorOccurred.addListener( onErrorOccurredHandler, { 'urls': [ "http://*/*", "https://*/*" ] } ); /******************************************************************************/ return { blockedRootFramePrefix: 'data:text/html;base64,' + btoa(rootFrameReplacement).slice(0, 80) }; /******************************************************************************/ })(); /******************************************************************************/