new redirect engine: this fixes #949 (the video ad part)

assets/checksums.txt

@@ -4,6 +4,7 @@ b2dbf435507aa0262b289c67cbef2142 assets/ublock/filters.txt
 146704ad1c0393e342afdb416762c183 assets/ublock/badware.txt
 c9c5cc56bec563bc1885847f925b9be2 assets/ublock/mirror-candidates.txt
 f9455a47b5024cc08ff3675ce79b58a9 assets/ublock/filter-lists.json
+a37de4c1166ed23c273d44611142b5e4 assets/ublock/redirect-rules.txt
 94c0a3eab74c42783855f07b22a429cf assets/thirdparties/home.fredfiber.no/langsholt/adblock.txt
 a82cb5ba5caf035ce00e97de81db5de7 assets/thirdparties/www.zoso.ro/pages/rolist.txt
 72373316d0e7ad22604d307c2d93e7cc assets/thirdparties/adblock.gardar.net/is.abp.txt

assets/ublock/redirect-rules.txt

@@ -0,0 +1,22 @@
+redirects:
+
+  hd-main.js application/javascript
+    var L = (function(){
+      var l = {};
+      var fn = function(){};
+      var props = ["pf","ed","Qe","fd","xh","Uc","ef","zd","Ad","Qc","Ri","Wc","Vc","Xc","Wg","rd","qd","sd","Pe","Id","Hd","Jd","fg","Fd","Ed","Gd","ek","Cd","Bd","Dd","Nj","Sc","Rc","Tc","wg","xd","wd","yd","fh","ld","md","nd","Re","cd","Pc","ke","Yc","Xg","jd","kd","oh","ad","bd","mi","gd","hd","ae","dd","fk","ij","ud","td","vd","ig","od","pd","Yd","$j","Oc","bf"];
+      for ( var i = 0; i < props.length; i++ ) {
+        l[props[i]] = fn;
+      }
+      return l;
+    })();
+
+rules:
+
+  # Prevent difficult to block video ads. Examples:
+  #   http://www.chip.de/news/Halbvoll-in-2-Minuten-Huawei-zeigt-neue-Superakkus_85752247.html
+  # Block filters to use:
+  #   ||s3.amazonaws.com/homad-global-configs.schneevonmorgen.com/hd-main.js$script,domain=cdnapi.kaltura.com,important
+  #   ||hgc.svonm.com/hd-main.js$script,domain=cdnapi.kaltura.com,important
+  cdnapi.kaltura.com s3.amazonaws.com script /\/hd-main.js$/ hd-main.js
+  cdnapi.kaltura.com    hgc.svonm.com script /\/hd-main.js$/ hd-main.js

src/background.html

@@ -15,6 +15,7 @@
 <script src="js/utils.js"></script>
 <script src="js/uritools.js"></script>
 <script src="js/assets.js"></script>
+<script src="js/redirect-engine.js"></script>
 <script src="js/dynamic-net-filtering.js"></script>
 <script src="js/static-net-filtering.js"></script>
 <script src="js/url-net-filtering.js"></script>

src/js/redirect-engine.js

@@ -0,0 +1,192 @@
+/*******************************************************************************
+
+    uBlock Origin - a browser extension to block requests.
+    Copyright (C) 2015 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
+*/
+
+/* global µBlock */
+
+/******************************************************************************/
+
+µBlock.redirectEngine = (function(){
+
+'use strict';
+
+/******************************************************************************/
+
+var toBroaderHostname = function(hostname) {
+    if ( hostname === '*' ) {
+        return '';
+    }
+    var pos = hostname.indexOf('.');
+    if ( pos === -1 ) {
+        return '*';
+    }
+    return hostname.slice(pos + 1);
+};
+
+/******************************************************************************/
+
+var RedirectEngine = function() {
+    this.reset();
+};
+
+/******************************************************************************/
+
+RedirectEngine.prototype.reset = function() {
+    this.redirects = Object.create(null);
+    this.rules = Object.create(null);
+};
+
+/******************************************************************************/
+
+RedirectEngine.prototype.lookup = function(context) {
+    var typeEntry = this.rules[context.requestType];
+    if ( typeEntry === undefined ) {
+        return;
+    }
+    var src, des = context.requestHostname,
+        srcHostname = context.pageHostname,
+        reqURL = context.requestURL,
+        desEntry, entries, i, entry;
+    for (;;) {
+        desEntry = typeEntry[des];
+        if ( desEntry !== undefined ) {
+            src = srcHostname;
+            for (;;) {
+                entries = desEntry[src];
+                if ( entries !== undefined ) {
+                    i = entries.length;
+                    while ( i-- ) {
+                        entry = entries[i];
+                        if ( entry.c.test(reqURL) ) {
+                            return this.redirects[entry.r];
+                        }
+                    }
+                }
+            }
+            src = toBroaderHostname(src);
+            if ( src === '' ) {
+                break;
+            }
+        }
+        des = toBroaderHostname(des);
+        if ( des === '' ) {
+            break;
+        }
+    }
+};
+
+/******************************************************************************/
+
+// TODO: combine same key-redirect pairs into a single regex.
+
+RedirectEngine.prototype.fromString = function(text) {
+    var textEnd = text.length;
+    var lineBeg = 0, lineEnd;
+    var mode, modeData, line, fields, encoded, data;
+    var reSource, typeEntry, desEntry, ruleEntries;
+
+    this.reset();
+
+    while ( lineBeg < textEnd ) {
+        lineEnd = text.indexOf('\n', lineBeg);
+        if ( lineEnd < 0 ) {
+            lineEnd = text.indexOf('\r', lineBeg);
+            if ( lineEnd < 0 ) {
+                lineEnd = textEnd;
+            }
+        }
+        line = text.slice(lineBeg, lineEnd).trim();
+        lineBeg = lineEnd + 1;
+
+        if ( line.charAt(0) === '#' ) {
+            continue;
+        }
+
+        if ( line.slice(-1) === ':' ) {
+            mode = line.slice(0, -1);
+            continue;
+        }
+
+        if ( mode === 'redirects' ) {
+            fields = line.split(/\s+/);
+            if ( fields.length !== 2 ) {
+                continue;
+            }
+            mode = 'redirects/redirect';
+            modeData = fields;
+            continue;
+        }
+
+        if ( mode === 'redirects/redirect' ) {
+            if ( line !== '' ) {
+                modeData.push(line);
+                continue;
+            }
+            encoded = modeData[1].indexOf(';') !== -1;
+            data = modeData.slice(2).join(encoded ? '' : '\n');
+            this.redirects[modeData[0]] =
+                'data:' +
+                modeData[1] + 
+                (encoded ? '' : ';base64') +
+                ',' +
+                (encoded ? data : btoa(data));
+            mode = 'redirects';
+            continue;
+        }
+
+        if ( mode === 'rules' ) {
+            fields = line.split(/\s+/);
+            if ( fields.length !== 5 ) {
+                continue;
+            }
+            reSource = fields[3];
+            if ( reSource.charAt(0) !== '/' || reSource.slice(-1) !== '/' ) {
+                reSource = reSource.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
+            } else {
+                reSource = reSource.slice(1, -1);
+            }
+            typeEntry = this.rules[fields[2]];
+            if ( typeEntry === undefined ) {
+                typeEntry = this.rules[fields[2]] = Object.create(null);
+            }
+            desEntry = typeEntry[fields[1]];
+            if ( desEntry === undefined ) {
+                desEntry = typeEntry[fields[1]] = Object.create(null);
+            }
+            ruleEntries = desEntry[fields[0]];
+            if ( ruleEntries === undefined ) {
+                ruleEntries = desEntry[fields[0]] = [];
+            }
+            ruleEntries.push({
+                c: new RegExp(reSource),
+                r: fields[4]
+            });
+            continue;
+        }
+    }
+};
+
+/******************************************************************************/
+
+return new RedirectEngine();
+
+/******************************************************************************/
+
+})();

src/js/start.js

@@ -211,6 +211,7 @@ var onFirstFetchReady = function(fetched) {
     fromFetch(µb.restoreBackupSettings, fetched);
     onNetWhitelistReady(fetched.netWhitelist);
     onVersionReady(fetched.version);
+    µb.loadRedirectRules();
 
     // If we have a selfie, skip loading PSL, filters
     if ( onSelfieReady(fetched.selfie) ) {

src/js/storage.js

@@ -646,6 +646,26 @@
 
 /******************************************************************************/
 
+// TODO: toSelfie/fromSelfie.
+
+µBlock.loadRedirectRules = function(callback) {
+    var µb = this;
+
+    if ( typeof callback !== 'function' ) {
+        callback = this.noopFunc;
+    }
+    var onRulesLoaded = function(details) {
+        if ( details.content !== '' ) {
+            µb.redirectEngine.fromString(details.content);
+        }
+        callback();
+    };
+
+    this.assets.get('assets/ublock/redirect-rules.txt', onRulesLoaded);
+};
+
+/******************************************************************************/
+
 µBlock.loadPublicSuffixList = function(callback) {
     var µb = this;
     var path = µb.pslPath;

src/js/traffic.js

@@ -131,9 +131,12 @@ var onBeforeRequest = function(details) {
         µb.updateBadgeAsync(tabId);
     }
 
-    // https://github.com/chrisaljoudi/uBlock/issues/18
-    // Do not use redirection, we need to block outright to be sure the request
-    // will not be made. There can be no such guarantee with redirection.
+    // https://github.com/gorhill/uBlock/issues/949
+    // Redirect blocked request?
+    var url = µb.redirectEngine.lookup(requestContext);
+    if ( url !== undefined ) {
+        return { redirectUrl: url };
+    }
 
     return { cancel: true };
 };