Apply meta tag referrer policy for preloaded requests

Source/core/html/parser/HTMLPreloadScanner.cpp

 /*
  * Copyright (C) 2008 Apple Inc. All Rights Reserved.
  * Copyright (C) 2009 Torch Mobile, Inc. http://www.torchmobile.com/
  * Copyright (C) 2010 Google Inc. All Rights Reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
@@ skipping 432 matching lines @@
     const Checkpoint& checkpoint = m_checkpoints[checkpointIndex];
     m_predictedBaseElementURL = checkpoint.predictedBaseElementURL;
     m_inStyle = checkpoint.inStyle;
     m_isAppCacheEnabled = checkpoint.isAppCacheEnabled;
     m_isCSPEnabled = checkpoint.isCSPEnabled;
     m_templateCount = checkpoint.templateCount;
     m_cssScanner.reset();
     m_checkpoints.clear();
 }
 
-void TokenPreloadScanner::scan(const HTMLToken& token, const SegmentedString& source, PreloadRequestStream& requests)
+void TokenPreloadScanner::scan(const HTMLToken& token, const SegmentedString& source, PreloadRequestStream& requests, String* preloadedReferrerPolicy)
 {
-    scanCommon(token, source, requests);
+    scanCommon(token, source, requests, preloadedReferrerPolicy);
 }
 
-void TokenPreloadScanner::scan(const CompactHTMLToken& token, const SegmentedString& source, PreloadRequestStream& requests)
+void TokenPreloadScanner::scan(const CompactHTMLToken& token, const SegmentedString& source, PreloadRequestStream& requests, String* preloadedReferrerPolicy)
 {
-    scanCommon(token, source, requests);
+    scanCommon(token, source, requests, preloadedReferrerPolicy);
 }
 
 static void handleMetaViewport(const String& attributeValue, CachedDocumentParameters* documentParameters)
 {
     if (!documentParameters->viewportMetaEnabled)
         return;
     ViewportDescription description(ViewportDescription::ViewportMeta);
     HTMLMetaElement::getViewportDescriptionFromContentAttribute(attributeValue, description, nullptr, documentParameters->viewportMetaZeroValuesQuirk);
     FloatSize initialViewport(documentParameters->mediaValues->viewportHeight(), documentParameters->mediaValues->viewportWidth());
     PageScaleConstraints constraints = description.resolve(initialViewport, documentParameters->defaultViewportMinWidth);
     MediaValuesCached* cachedMediaValues = static_cast<MediaValuesCached*>(documentParameters->mediaValues.get());
     cachedMediaValues->setViewportHeight(constraints.layoutSize.height());
     cachedMediaValues->setViewportWidth(constraints.layoutSize.width());
 }
 
-template<typename Token>
-void TokenPreloadScanner::scanCommon(const Token& token, const SegmentedString& source, PreloadRequestStream& requests)
+template <typename Token>
+void TokenPreloadScanner::scanCommon(const Token& token, const SegmentedString& source, PreloadRequestStream& requests, String* preloadedReferrerPolicy)
 {
     if (!m_documentParameters->doHtmlPreloadScanning)
         return;
 
     // Disable preload for documents with AppCache.
     if (m_isAppCacheEnabled)
         return;
 
     // http://crbug.com/434230 Disable preload for documents with CSP <meta> tags
     if (m_isCSPEnabled)
@@ skipping 59 matching lines @@
                 }
                 return;
             }
             const typename Token::Attribute* nameAttribute = token.getAttributeItem(nameAttr);
             if (nameAttribute && equalIgnoringCase(String(nameAttribute->value), "viewport")) {
                 const typename Token::Attribute* contentAttribute = token.getAttributeItem(contentAttr);
                 if (contentAttribute)
                     handleMetaViewport(String(contentAttribute->value), m_documentParameters.get());
                 return;
             }
+            if (nameAttribute && equalIgnoringCase(String(nameAttribute->value), "referrer")) {
+                const typename Token::Attribute* contentAttribute = token.getAttributeItem(contentAttr);
+                if (contentAttribute)
+                    *preloadedReferrerPolicy = String(contentAttribute->value).isolatedCopy();
+            }
         }
 
         if (match(tagImpl, pictureTag)) {
             m_inPicture = true;
             m_pictureData = PictureData();
             return;
         }
 
         StartTagScanner scanner(tagImpl, m_documentParameters->mediaValues);
         scanner.processAttributes(token.attributes());
@@ skipping 39 matching lines @@
 {
     ASSERT(isMainThread()); // HTMLTokenizer::updateStateFor only works on the main thread.
 
     TRACE_EVENT1("blink", "HTMLPreloadScanner::scan", "source_length", m_source.length());
 
     // When we start scanning, our best prediction of the baseElementURL is the real one!
     if (!startingBaseElementURL.isEmpty())
         m_scanner.setPredictedBaseElementURL(startingBaseElementURL);
 
     PreloadRequestStream requests;
+    String preloadedReferrerPolicy;
 
     while (m_tokenizer->nextToken(m_source, m_token)) {
         if (m_token.type() == HTMLToken::StartTag)
             m_tokenizer->updateStateFor(attemptStaticStringCreation(m_token.name(), Likely8Bit));
-        m_scanner.scan(m_token, m_source, requests);
+        m_scanner.scan(m_token, m_source, requests, &preloadedReferrerPolicy);
         m_token.clear();
     }
 
+    if (!preloadedReferrerPolicy.isEmpty())
+        preloader->preloadReferrerPolicy(preloadedReferrerPolicy);
+
     preloader->takeAndPreload(requests);
 }
 
 CachedDocumentParameters::CachedDocumentParameters(Document* document, PassRefPtr<MediaValues> givenMediaValues)
 {
     ASSERT(isMainThread());
     ASSERT(document);
     doHtmlPreloadScanning = !document->settings() || document->settings()->doHtmlPreloadScanning();
     if (givenMediaValues)
         mediaValues = givenMediaValues;
     else
         mediaValues = MediaValuesCached::create(*document);
     ASSERT(mediaValues->isSafeToSendToAnotherThread());
     defaultViewportMinWidth = document->viewportDefaultMinWidth();
     viewportMetaZeroValuesQuirk = document->settings() && document->settings()->viewportMetaZeroValuesQuirk();
     viewportMetaEnabled = document->settings() && document->settings()->viewportMetaEnabled();
 }
 
 }