Optimize checking if PB is disabled for a site

Author: ghostwords

src/js/background.js

@@ -16,6 +16,7 @@
  */
 
 import { extractHostFromURL, getBaseDomain } from "../lib/basedomain.js";
+import { Trie } from "../lib/trie.js";
 
 import { log } from "./bootstrap.js";
 import constants from "./constants.js";
@@ -106,6 +107,8 @@ function Badger(from_qunit) {
   async function onStorageReady() {
     log("Storage is ready");
 
+    self.initDisabledSitesTrie();
+
     self.heuristicBlocking = new HeuristicBlocking.HeuristicBlocker(self.storage);
 
     self.setPrivacyOverrides();
@@ -176,6 +179,11 @@ Badger.prototype = {
    */
   cnameDomains: {},
 
+  /**
+   * Trie for looking up whether PB is disabled for a site.
+   */
+  disabledSitesTrie: null,
+
   // Methods
 
   /**
@@ -1013,6 +1021,27 @@ Badger.prototype = {
     return this.storage.getStore('private_storage');
   },
 
+  /**
+   * (Re)builds the disabled sites trie.
+   */
+  initDisabledSitesTrie: function () {
+    let self = this;
+
+    self.disabledSitesTrie = new Trie();
+
+    for (let pattern of self.getSettings().getItem("disabledSites")) {
+      // domains now always match subdomains
+      // TODO clean up user data and remove wildcard handling
+      if (pattern.startsWith('*')) {
+        pattern = pattern.slice(1);
+        if (pattern.startsWith('.')) {
+          pattern = pattern.slice(1);
+        }
+      }
+      self.disabledSitesTrie.insert(pattern);
+    }
+  },
+
   /**
    * Returns whether Privacy Badger is enabled on a given hostname.
    *
@@ -1021,23 +1050,51 @@ Badger.prototype = {
    * @returns {Boolean}
    */
   isPrivacyBadgerEnabled: function (host) {
-    let sitePatterns = this.getSettings().getItem("disabledSites") || [];
+    return !this.disabledSitesTrie.globDomainMatches(host);
+  },
+
+  /**
+   * Adds a domain to the list of disabled sites.
+   *
+   * @param {String} domain The site domain to disable PB for
+   */
+  disableOnSite: function (domain) {
+    let self = this,
+      settings = self.getSettings(),
+      disabledSites = settings.getItem('disabledSites');
+
+    if (!disabledSites.includes(domain)) {
+      disabledSites.push(domain);
+      settings.setItem("disabledSites", disabledSites);
 
-    for (let pattern of sitePatterns) {
       // domains now always match subdomains
       // TODO clean up user data and remove wildcard handling
-      if (pattern.startsWith('*')) {
-        pattern = pattern.slice(1);
-        if (pattern.startsWith('.')) {
-          pattern = pattern.slice(1);
+      if (domain.startsWith('*')) {
+        domain = domain.slice(1);
+        if (domain.startsWith('.')) {
+          domain = domain.slice(1);
         }
       }
-      if (pattern === host || host.endsWith('.' + pattern)) {
-        return false;
-      }
+      self.disabledSitesTrie.insert(domain);
     }
+  },
 
-    return true;
+  /**
+   * Removes a domain from the list of disabled sites.
+   *
+   * @param {String} domain The site domain to re-enable PB on
+   */
+  reenableOnSite: function (domain) {
+    let self = this,
+      settings = self.getSettings(),
+      disabledSites = settings.getItem("disabledSites"),
+      idx = disabledSites.indexOf(domain);
+
+    if (idx >= 0) {
+      disabledSites.splice(idx, 1);
+      settings.setItem("disabledSites", disabledSites);
+      self.initDisabledSitesTrie();
+    }
   },
 
   /**
@@ -1075,44 +1132,6 @@ Badger.prototype = {
     return this.getSettings().getItem("checkForDNTPolicy");
   },
 
-  /**
-   * Adds a domain to the list of disabled sites.
-   *
-   * @param {String} domain The site domain to disable PB for
-   */
-  disableOnSite: function (domain) {
-    let settings = this.getSettings();
-    let disabledSites = settings.getItem('disabledSites');
-    if (disabledSites.indexOf(domain) < 0) {
-      disabledSites.push(domain);
-      settings.setItem("disabledSites", disabledSites);
-    }
-  },
-
-  /**
-   * Returns the current list of disabled sites.
-   *
-   * @returns {Array} site domains where Privacy Badger is disabled
-   */
-  getDisabledSites: function () {
-    return this.getSettings().getItem("disabledSites");
-  },
-
-  /**
-   * Removes a domain from the list of disabled sites.
-   *
-   * @param {String} domain The site domain to re-enable PB on
-   */
-  reenableOnSite: function (domain) {
-    let settings = this.getSettings();
-    let disabledSites = settings.getItem("disabledSites");
-    let idx = disabledSites.indexOf(domain);
-    if (idx >= 0) {
-      disabledSites.splice(idx, 1);
-      settings.setItem("disabledSites", disabledSites);
-    }
-  },
-
   /**
    * Checks if local storage ( in dict) has any high-entropy keys
    *

src/js/webrequest.js

@@ -1666,7 +1666,7 @@ function dispatcher(request, sender, sendResponse) {
         sendResponse({success: false, message: chrome.runtime.lastError.message});
       } else if (utils.hasOwn(store, "disabledSites")) {
         let disabledSites = utils.concatUniq(
-          badger.getDisabledSites(),
+          badger.getSettings().getItem("disabledSites"),
           store.disabledSites
         );
         badger.getSettings().setItem("disabledSites", disabledSites);
@@ -1688,7 +1688,7 @@ function dispatcher(request, sender, sendResponse) {
 
   case "uploadCloud": {
     let obj = {};
-    obj.disabledSites = badger.getDisabledSites();
+    obj.disabledSites = badger.getSettings().getItem("disabledSites");
     chrome.storage.sync.set(obj, function () {
       if (chrome.runtime.lastError) {
         sendResponse({success: false, message: chrome.runtime.lastError.message});
@@ -1767,7 +1767,7 @@ function dispatcher(request, sender, sendResponse) {
   case "disableOnSite": {
     badger.disableOnSite(request.domain);
     sendResponse({
-      disabledSites: badger.getDisabledSites()
+      disabledSites: badger.getSettings().getItem("disabledSites")
     });
     break;
   }
@@ -1777,7 +1777,7 @@ function dispatcher(request, sender, sendResponse) {
       badger.reenableOnSite(domain);
     });
     sendResponse({
-      disabledSites: badger.getDisabledSites()
+      disabledSites: badger.getSettings().getItem("disabledSites")
     });
     break;
   }

src/lib/trie.js

@@ -0,0 +1,157 @@
+/*
+ * This file is part of Privacy Badger <https://privacybadger.org/>
+ * Copyright (C) 2025 Electronic Frontier Foundation
+ *
+ * Privacy Badger is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 as
+ * published by the Free Software Foundation.
+ *
+ * Privacy Badger 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 Privacy Badger.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+import utils from "../js/utils.js";
+
+/**
+ * Trie node constructor.
+ *
+ * @param {String?} key
+ */
+function TrieNode(key) {
+  this.key = key;
+  this.parentNode = null;
+  this.stringEndsHere = false;
+  this.children = {};
+}
+
+/**
+ * Iterates through parent nodes to reconstruct the dot-separated string.
+ */
+TrieNode.prototype.getString = function () {
+  let output = [],
+    node = this; // eslint-disable-line consistent-this
+
+  for (;;) {
+    // stop at the root node
+    if (node.key === null) {
+      break;
+    }
+    output.push(node.key);
+    node = node.parentNode;
+  }
+
+  return output.join('.');
+};
+
+/**
+ * Recursively populates `arr` with full strings
+ * belonging to children of a given TrieNode.
+ *
+ * @param {TrieNode} node
+ * @param {Array} arr
+ */
+function findAll(node, arr) {
+  if (node.stringEndsHere) {
+    arr.push(node.getString());
+  }
+
+  for (let key of Object.keys(node.children)) {
+    findAll(node.children[key], arr);
+  }
+}
+
+/**
+ * Domain trie constructor.
+ */
+function Trie() {
+  this.root = new TrieNode(null);
+}
+
+/*
+ * Inserts a dot-separated domain string into the trie.
+ *
+ * @param {String} domain
+ */
+Trie.prototype.insert = function (domain) {
+  let node = this.root,
+    parts = domain.split('.');
+
+  for (let i = parts.length-1; i >= 0; i--) {
+    let key = parts[i];
+
+    if (!utils.hasOwn(node.children, key)) {
+      node.children[key] = new TrieNode(key);
+      node.children[key].parentNode = node;
+    }
+
+    node = node.children[key];
+
+    if (i == 0) {
+      node.stringEndsHere = true;
+    }
+  }
+};
+
+/**
+ * Returns any subdomains and the domain itself, if inserted directly.
+ *
+ * Note that the order of strings is undefined.
+ *
+ * @param {String} domain
+ *
+ * @returns {Array}
+ */
+Trie.prototype.getDomains = function (domain) {
+  let domains = [],
+    node = this.root,
+    parts = domain.split('.');
+
+  // first navigate to the deepest TrieNode for domain
+  for (let i = parts.length-1; i >= 0; i--) {
+    let key = parts[i];
+    if (!utils.hasOwn(node.children, key)) {
+      // abort if domain isn't fully in the Trie
+      return domains;
+    }
+    node = node.children[key];
+  }
+
+  findAll(node, domains);
+
+  return domains;
+};
+
+/**
+ * Returns whether the domain string, or any of its
+ * parent domain strings were inserted into the trie.
+ *
+ * @param {String} domain
+ *
+ * @returns {Boolean}
+ */
+Trie.prototype.globDomainMatches = function (domain) {
+  let parts = domain.split('.'),
+    node = this.root;
+
+  for (let i = parts.length-1; i >= 0; i--) {
+    let key = parts[i];
+    if (!utils.hasOwn(node.children, key)) {
+      return false;
+    }
+    node = node.children[key];
+    if (node.stringEndsHere) {
+      return true;
+    }
+  }
+
+  return false;
+};
+
+export {
+  Trie
+};

src/tests/index.html

@@ -48,6 +48,7 @@
     <script type="module" src="tests/options.js"></script>
     <script type="module" src="tests/storage.js"></script>
     <script type="module" src="tests/tabData.js"></script>
+    <script type="module" src="tests/trie.js"></script>
     <!-- URL/host tools: --><script type="module" src="tests/baseDomain.js"></script>
     <script type="module" src="tests/utils.js"></script>
     <script type="module" src="tests/yellowlist.js"></script>

src/tests/lib/qunit_config.js

@@ -39,6 +39,9 @@
       let store = badger.storage.getStore(store_name);
       BACKUP[store_name] = store.getItemClones();
     });
+
+    BACKUP.disabledSitesTrie = badger.disabledSitesTrie;
+    badger.initDisabledSitesTrie();
   });
 
   QUnit.testDone(() => {
@@ -47,6 +50,8 @@
       let store = badger.storage.getStore(store_name);
       store._store = BACKUP[store_name];
     });
+
+    badger.disabledSitesTrie = BACKUP.disabledSitesTrie;
   });
 
   // kick off tests when we have what we need from Badger