From 5921e50e03bf2f86550ef16b0a72bf6c0bbda8f3 Mon Sep 17 00:00:00 2001
From: Raymond Hill <rhill@raymondhill.net>
Date: Thu, 20 Feb 2025 15:11:36 -0500
Subject: [PATCH] Fix reverse lookup of `##^responseheader(...)` filters

Related issue:
https://github.com/uBlockOrigin/uBlock-issues/issues/3544
---
 src/js/httpheader-filtering.js    |  4 +---
 src/js/reverselookup-worker.js    | 12 ++++++++++--
 src/js/reverselookup.js           | 10 ++++++----
 src/js/static-filtering-parser.js |  6 ++++++
 4 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/src/js/httpheader-filtering.js b/src/js/httpheader-filtering.js
index 58781fb61..20f83219b 100644
--- a/src/js/httpheader-filtering.js
+++ b/src/js/httpheader-filtering.js
@@ -19,7 +19,6 @@
     Home: https://github.com/gorhill/uBlock
 */
 
-import * as sfp from './static-filtering-parser.js';
 import { StaticExtFilteringHostnameDB } from './static-ext-filtering-db.js';
 import { entityFromDomain } from './uri-utils.js';
 import logger from './logger.js';
@@ -83,8 +82,7 @@ httpheaderFilteringEngine.compile = function(parser, writer) {
     writer.select('HTTPHEADER_FILTERS');
 
     const isException = parser.isException();
-    const root = parser.getBranchFromType(sfp.NODE_TYPE_EXT_PATTERN_RESPONSEHEADER);
-    const headerName = parser.getNodeString(root);
+    const headerName = parser.getResponseheaderName();
 
     // Tokenless is meaningful only for exception filters.
     if ( headerName === '' && isException === false ) { return; }
diff --git a/src/js/reverselookup-worker.js b/src/js/reverselookup-worker.js
index ffdf56686..1cad3cf02 100644
--- a/src/js/reverselookup-worker.js
+++ b/src/js/reverselookup-worker.js
@@ -120,7 +120,7 @@ const fromExtendedFilter = function(details) {
     // 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 = selector.match(/\w+|\*/g).reduce(function(a, b) {
+    const needle = (details.needle || selector).match(/\w+|\*/g).reduce(function(a, b) {
         return a.length > b.length ? a : b;
     });
 
@@ -213,6 +213,12 @@ const fromExtendedFilter = function(details) {
             /* fallthrough */
             case 64: {
                 if ( exception !== ((fargs[2] & 0b001) !== 0) ) { break; }
+                if ( /^responseheader\(.+\)$/.test(selector) ) {
+                    if ( fargs[3] !== needle ) { break; }
+                    if ( hostnameMatches(fargs[1]) === false ) { break; }
+                    found = fargs[1] + prefix + selector;
+                    break;
+                }
                 const isProcedural = (fargs[2] & 0b010) !== 0;
                 if (
                     isProcedural === false && fargs[3] !== selector ||
@@ -236,11 +242,13 @@ const fromExtendedFilter = function(details) {
             // Scriptlet injection
             case 32:
                 if ( exception !== ((fargs[2] & 0b001) !== 0) ) { break; }
-                if ( fargs[3] !== details.compiled ) { break; }
+                if ( fargs[3] !== details.needle ) { break; }
                 if ( hostnameMatches(fargs[1]) ) {
                     found = fargs[1] + prefix + selector;
                 }
                 break;
+            default:
+                break;
             }
             if ( found !== undefined  ) {
                 if ( response[found] === undefined ) {
diff --git a/src/js/reverselookup.js b/src/js/reverselookup.js
index e1fa006d4..7a0bfb04c 100644
--- a/src/js/reverselookup.js
+++ b/src/js/reverselookup.js
@@ -93,7 +93,7 @@ const initWorker = function() {
     };
 
     for ( const listKey in µb.availableFilterLists ) {
-        if ( µb.availableFilterLists.hasOwnProperty(listKey) === false ) {
+        if ( Object.prototype.hasOwnProperty.call(µb.availableFilterLists, listKey) === false ) {
             continue;
         }
         const entry = µb.availableFilterLists[listKey];
@@ -167,9 +167,11 @@ const fromExtendedFilter = async function(details) {
         nativeCssHas: vAPI.webextFlavor.env.includes('native_css_has'),
     });
     parser.parse(details.rawFilter);
-    let compiled;
+    let needle;
     if ( parser.isScriptletFilter() ) {
-        compiled = JSON.stringify(parser.getScriptletArgs());
+        needle = JSON.stringify(parser.getScriptletArgs());
+    } else if ( parser.isResponseheaderFilter() ) {
+        needle = parser.getResponseheaderName();
     }
 
     worker.postMessage({
@@ -188,7 +190,7 @@ const fromExtendedFilter = async function(details) {
                 details.url
             ) === 2,
         rawFilter: details.rawFilter,
-        compiled,
+        needle,
     });
 
     return new Promise(resolve => {
diff --git a/src/js/static-filtering-parser.js b/src/js/static-filtering-parser.js
index 73507cc6b..9315460a6 100644
--- a/src/js/static-filtering-parser.js
+++ b/src/js/static-filtering-parser.js
@@ -2494,6 +2494,12 @@ export class AstFilterParser {
         return head;
     }
 
+    getResponseheaderName() {
+        if ( this.isResponseheaderFilter() === false ) { return ''; }
+        const root = this.getBranchFromType(NODE_TYPE_EXT_PATTERN_RESPONSEHEADER);
+        return this.getNodeString(root);
+    }
+
     parseExtPatternHtml(parent) {
         const beg = this.nodes[parent+NODE_BEG_INDEX];
         const end = this.nodes[parent+NODE_END_INDEX];