From 5cbe583c0aa08c9698857862db92cfff8b9c7634 Mon Sep 17 00:00:00 2001
From: gorhill <rhill@raymondhill.net>
Date: Tue, 23 Aug 2016 10:33:28 -0400
Subject: [PATCH] fix #1929

---
 src/js/logger-ui.js            | 18 +++++++--
 src/js/static-net-filtering.js | 72 ++++++++++++++++++----------------
 2 files changed, 53 insertions(+), 37 deletions(-)

diff --git a/src/js/logger-ui.js b/src/js/logger-ui.js
index 398b664fb..ae3d90dc7 100644
--- a/src/js/logger-ui.js
+++ b/src/js/logger-ui.js
@@ -309,14 +309,24 @@ var filterDecompiler = (function() {
         case 'a|h':
         case '_':
         case '_h':
+            reStr = tfields[0]
+                .replace(reEscape, '\\$&')
+                .replace(reWildcards, '.*?')
+                .replace(reSeparator, '(?:[^%.0-9a-z_-]|$)');
+            break;
         case '||a':
         case '||ah':
         case '||_':
         case '||_h':
-            reStr = tfields[0]
-                    .replace(reEscape, '\\$&')
-                    .replace(reWildcards, '.*')
-                    .replace(reSeparator, '(?:[^%.0-9a-z_-]|$)');
+            reStr = '';
+            if ( tfields[0].charCodeAt(0) === 0x2A ) {
+                reStr = '[0-9a-z.-]*?';
+                tfields[0] = tfields[0].slice(1);
+            }
+            reStr += tfields[0]
+                .replace(reEscape, '\\$&')
+                .replace(reWildcards, '.*?')
+                .replace(reSeparator, '(?:[^%.0-9a-z_-]|$)');
             break;
         case '//':
         case '//h':
diff --git a/src/js/static-net-filtering.js b/src/js/static-net-filtering.js
index bdca79f3a..e06589132 100644
--- a/src/js/static-net-filtering.js
+++ b/src/js/static-net-filtering.js
@@ -105,8 +105,6 @@ var AllowAnyTypeAnyParty = AllowAction | AnyType | AnyParty;
 var AllowAnyType = AllowAction | AnyType;
 var AllowAnyParty = AllowAction | AnyParty;
 
-var reURLPostHostnameAnchors = /[\/?#]/;
-
 // ABP filters: https://adblockplus.org/en/filters
 // regex tester: http://regex101.com/
 
@@ -206,7 +204,11 @@ var strToRegex = function(s, anchor, flags) {
     if ( s === '*' ) {
         return alwaysTruePseudoRegex;
     }
-
+    var anchorToHnStart;
+    if ( s.startsWith('||') ) {
+        s = s.slice(2);
+        anchorToHnStart = s.charCodeAt(0) === 0x2A;
+    }
     // https://www.loggly.com/blog/five-invaluable-techniques-to-improve-regex-performance/
     // https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions
     // Also: remove leading/trailing wildcards -- there is no point.
@@ -220,7 +222,9 @@ var strToRegex = function(s, anchor, flags) {
     } else if ( anchor > 0 ) {
         reStr += '$';
     }
-
+    if ( anchorToHnStart ) {
+        reStr = '[0-9a-z.-]*?' + reStr;
+    }
     //console.debug('µBlock.staticNetFilteringEngine: created RegExp("%s")', reStr);
     return new RegExp(reStr, flags);
 };
@@ -229,6 +233,26 @@ var toHex = function(n) {
     return n.toString(16);
 };
 
+// First character of match must be within the hostname part of the url.
+var isHnAnchored = function(url, matchStart) {
+    var hnStart = url.indexOf('://');
+    if ( hnStart === -1 ) {
+        return false;
+    }
+    hnStart += 3;
+    if ( matchStart <= hnStart ) {
+        return true;
+    }
+    if ( reURLPostHostnameAnchors.test(url.slice(hnStart, matchStart)) ) {
+        return false;
+    }
+    // https://github.com/gorhill/uBlock/issues/1929
+    // Match only hostname label boundaries.
+    return url.charCodeAt(matchStart - 1) === 0x2E;
+};
+
+var reURLPostHostnameAnchors = /[\/?#]/;
+
 /******************************************************************************/
 
 // Hostname test helpers: the optimal test function is picked
@@ -699,13 +723,8 @@ var FilterPlainHnAnchored = function(s) {
 };
 
 FilterPlainHnAnchored.prototype.match = function(url, tokenBeg) {
-    if ( url.startsWith(this.s, tokenBeg) === false ) {
-        return false;
-    }
-    // Valid only if hostname-valid characters to the left of token
-    var pos = url.indexOf('://');
-    return pos !== -1 &&
-           reURLPostHostnameAnchors.test(url.slice(pos + 3, tokenBeg)) === false;
+    return url.startsWith(this.s, tokenBeg) &&
+           isHnAnchored(url, tokenBeg);
 };
 
 FilterPlainHnAnchored.fid =
@@ -739,16 +758,9 @@ var FilterPlainHnAnchoredHostname = function(s, domainOpt) {
 };
 
 FilterPlainHnAnchoredHostname.prototype.match = function(url, tokenBeg) {
-    if (
-        url.startsWith(this.s, tokenBeg) === false ||
-        this.hostnameTest(this) === false
-    ) {
-        return false;
-    }
-    // Valid only if hostname-valid characters to the left of token
-    var pos = url.indexOf('://');
-    return pos !== -1 &&
-           reURLPostHostnameAnchors.test(url.slice(pos + 3, tokenBeg)) === false;
+    return url.startsWith(this.s, tokenBeg) &&
+           this.hostnameTest(this) &&
+           isHnAnchored(url, tokenBeg);
 };
 
 FilterPlainHnAnchoredHostname.fid =
@@ -852,18 +864,10 @@ var FilterGenericHnAnchored = function(s) {
 
 FilterGenericHnAnchored.prototype.match = function(url) {
     if ( this.re === null ) {
-        this.re = strToRegex(this.s, 0);
+        this.re = strToRegex('||' + this.s, 0);
     }
-    // Quick test first
-    if ( this.re.test(url) === false ) {
-        return false;
-    }
-    // Valid only if begininning of match is within the hostname
-    // part of the url
-    var match = this.re.exec(url);
-    var pos = url.indexOf('://');
-    return pos !== -1 &&
-           reURLPostHostnameAnchors.test(url.slice(pos + 3, match.index)) === false;
+    var matchStart = url.search(this.re);
+    return matchStart !== -1 && isHnAnchored(url, matchStart);
 };
 
 FilterGenericHnAnchored.fid =
@@ -2228,11 +2232,13 @@ FilterContainer.prototype.filterRegexFromCompiled = function(compiled, flags) {
     case '1ah':
     case '_':
     case '_h':
+        re = strToRegex(tfields[0], 0, flags);
+        break;
     case '||a':
     case '||ah':
     case '||_':
     case '||_h':
-        re = strToRegex(tfields[0], 0, flags);
+        re = strToRegex('||' + tfields[0], 0, flags);
         break;
     case '|a':
     case '|ah':