Issue 5175 - Reject element hiding filter with empty domain names

compiled/filter/ElemHideBase.cpp

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-present eyeo GmbH
  *
  * Adblock Plus 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.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 48 matching lines @@
   static constexpr String::value_type ELEM_HIDE_EMULATION_DELIMITER[] = u"#?#";
   static constexpr String::size_type ELEM_HIDE_EMULATION_DELIMITER_LEN = str_length_of(ELEM_HIDE_EMULATION_DELIMITER);
 
   static constexpr String::value_type OLD_PROPS_SELECTOR[] = u"[-abp-properties=";
   static constexpr String::size_type OLD_PROPS_SELECTOR_LEN = str_length_of(OLD_PROPS_SELECTOR);
 
   static constexpr String::value_type PROPS_SELECTOR[] = u":-abp-properties(";
   static constexpr String::size_type PROPS_SELECTOR_LEN = str_length_of(PROPS_SELECTOR);
 }
 
-ElemHideBase::ElemHideBase(Type type, const String& text, const ElemHideData& data)
+ElemHideBase::ElemHideBase(Type type, const String& text, const ElemHideData& data, const ParsedDomains& parsedDomains)
     : ActiveFilter(type, text, false), mData(data)
 {
   if (mData.HasDomains())
-    ParseDomains(mData.GetDomainsSource(mText), u',');
+    FillDomains(mData.GetDomainsSource(mText), parsedDomains);
 }
 
-Filter::Type ElemHideBase::Parse(DependentString& text, ElemHideData& data, bool& needConversion)
+Filter::Type ElemHideBase::Parse(DependentString& text, DependentString& error,
+                                 ElemHideData& data, bool& needConversion,
+                                 ParsedDomains& parsedDomains)
 {
   needConversion = false;
 
   StringScanner scanner(text);
 
   // Domains part
   bool seenSpaces = false;
   while (!scanner.done())
   {
     String::value_type next = scanner.next();
@@ skipping 37 matching lines @@
   if (scanner.done())
     return Type::UNKNOWN;
 
   data.mSelectorStart = scanner.position() + 1;
 
   // We are done validating, now we can normalize whitespace and the domain part
   if (seenSpaces)
     NormalizeWhitespace(text, data.mDomainsEnd, data.mSelectorStart);
   DependentString(text, 0, data.mDomainsEnd).toLower();
 
+  parsedDomains =
+    ParseDomainsInternal(data.GetDomainsSource(text), u',', false);
+  if (parsedDomains.hasEmpty)
+  {
+    error = u"filter_invalid_domain"_str;
+    return Type::INVALID;
+  }
   // We still need to check the old syntax. It will be converted when
   // we instantiate the filter.
   if (!emulation &&
       text.find(OLD_PROPS_SELECTOR, data.mSelectorStart, OLD_PROPS_SELECTOR_LEN) != text.npos)
   {
     needConversion = true;
     emulation = !exception;
   }
 
   if (exception)
@@ skipping 188 matching lines @@
       if (item.second && !item.first.empty())
       {
         if (!result.empty())
           result.append(u',');
         result.append(item.first);
       }
     }
   }
   return result;
 }