Preload tokens even if a <meta> csp tag is found

third_party/WebKit/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 479 matching lines @@
     bool m_referrerPolicySet;
     ReferrerPolicy m_referrerPolicy;
     IntegrityMetadataSet m_integrityMetadata;
 };
 
 TokenPreloadScanner::TokenPreloadScanner(const KURL& documentURL, std::unique_ptr<CachedDocumentParameters> documentParameters, const MediaValuesCached::MediaValuesCachedData& mediaValuesCachedData)
     : m_documentURL(documentURL)
     , m_inStyle(false)
     , m_inPicture(false)
     , m_inScript(false)
-    , m_isCSPEnabled(false)
     , m_templateCount(0)
     , m_documentParameters(std::move(documentParameters))
     , m_mediaValues(MediaValuesCached::create(mediaValuesCachedData))
     , m_didRewind(false)
 {
     ASSERT(m_documentParameters.get());
     ASSERT(m_mediaValues.get());
     m_cssScanner.setReferrerPolicy(m_documentParameters->referrerPolicy);
 }
 
 TokenPreloadScanner::~TokenPreloadScanner()
 {
 }
 
 TokenPreloadScannerCheckpoint TokenPreloadScanner::createCheckpoint()
 {
     TokenPreloadScannerCheckpoint checkpoint = m_checkpoints.size();
-    m_checkpoints.append(Checkpoint(m_predictedBaseElementURL, m_inStyle, m_inScript, m_isCSPEnabled, m_templateCount));
+    m_checkpoints.append(Checkpoint(m_predictedBaseElementURL, m_inStyle, m_inScript, m_templateCount));
     return checkpoint;
 }
 
 void TokenPreloadScanner::rewindTo(TokenPreloadScannerCheckpoint checkpointIndex)
 {
     ASSERT(checkpointIndex < m_checkpoints.size()); // If this ASSERT fires, checkpointIndex is invalid.
     const Checkpoint& checkpoint = m_checkpoints[checkpointIndex];
     m_predictedBaseElementURL = checkpoint.predictedBaseElementURL;
     m_inStyle = checkpoint.inStyle;
-    m_isCSPEnabled = checkpoint.isCSPEnabled;
     m_templateCount = checkpoint.templateCount;
 
     m_didRewind = true;
     m_inScript = checkpoint.inScript;
 
     m_cssScanner.reset();
     m_checkpoints.clear();
 }
 
-void TokenPreloadScanner::scan(const HTMLToken& token, const SegmentedString& source, PreloadRequestStream& requests, ViewportDescriptionWrapper* viewport)
+void TokenPreloadScanner::scan(const HTMLToken& token, const SegmentedString& source, PreloadRequestStream& requests, ViewportDescriptionWrapper* viewport, bool* isCSPMetaTag)
 {
-    scanCommon(token, source, requests, viewport, nullptr);
+    scanCommon(token, source, requests, viewport, isCSPMetaTag, nullptr);
 }
 
-void TokenPreloadScanner::scan(const CompactHTMLToken& token, const SegmentedString& source, PreloadRequestStream& requests, ViewportDescriptionWrapper* viewport, bool* likelyDocumentWriteScript)
+void TokenPreloadScanner::scan(const CompactHTMLToken& token, const SegmentedString& source, PreloadRequestStream& requests, ViewportDescriptionWrapper* viewport, bool* isCSPMetaTag, bool* likelyDocumentWriteScript)
 {
-    scanCommon(token, source, requests, viewport, likelyDocumentWriteScript);
+    scanCommon(token, source, requests, viewport, isCSPMetaTag, likelyDocumentWriteScript);
 }
 
 static void handleMetaViewport(const String& attributeValue, const CachedDocumentParameters* documentParameters, MediaValuesCached* mediaValues, ViewportDescriptionWrapper* viewport)
 {
     if (!documentParameters->viewportMetaEnabled)
         return;
     ViewportDescription description(ViewportDescription::ViewportMeta);
     HTMLMetaElement::getViewportDescriptionFromContentAttribute(attributeValue, description, nullptr, documentParameters->viewportMetaZeroValuesQuirk);
     if (viewport) {
         viewport->description = description;
@@ skipping 88 matching lines @@
     }
     if (source.find("Math.random") != WTF::kNotFound
         || source.find("Date") != WTF::kNotFound) {
         LogGatedEvaluation(GatedEvaluationNondeterminism);
         return false;
     }
     return true;
 }
 
 template <typename Token>
-void TokenPreloadScanner::scanCommon(const Token& token, const SegmentedString& source, PreloadRequestStream& requests, ViewportDescriptionWrapper* viewport, bool* likelyDocumentWriteScript)
+void TokenPreloadScanner::scanCommon(const Token& token, const SegmentedString& source, PreloadRequestStream& requests, ViewportDescriptionWrapper* viewport, bool* isCSPMetaTag, bool* likelyDocumentWriteScript)
 {
     if (!m_documentParameters->doHtmlPreloadScanning)
         return;
 
-    // http://crbug.com/434230 Disable preload for documents with CSP <meta> tags
-    if (m_isCSPEnabled)
-        return;
-
     switch (token.type()) {
     case HTMLToken::Character: {
         if (m_inStyle) {
             m_cssScanner.scan(token.data(), source, requests, m_predictedBaseElementURL);
         } else if (m_inScript && likelyDocumentWriteScript && !m_didRewind) {
             // Don't mark scripts for evaluation if the preloader rewound to a
             // previous checkpoint. This could cause re-evaluation of scripts if
             // care isn't given.
             // TODO(csharrison): Revisit this if rewinds are low hanging fruit for the
             // document.write evaluator.
@@ skipping 44 matching lines @@
             if (!m_predictedBaseElementURL.isEmpty())
                 return;
             updatePredictedBaseURL(token);
             return;
         }
         if (match(tagImpl, metaTag)) {
             const typename Token::Attribute* equivAttribute = token.getAttributeItem(http_equivAttr);
             if (equivAttribute) {
                 String equivAttributeValue(equivAttribute->value());
                 if (equalIgnoringCase(equivAttributeValue, "content-security-policy")) {
-                    m_isCSPEnabled = true;
+                    *isCSPMetaTag = true;
                 } else if (equalIgnoringCase(equivAttributeValue, "accept-ch")) {
                     const typename Token::Attribute* contentAttribute = token.getAttributeItem(contentAttr);
                     if (contentAttribute)
                         m_clientHintsPreferences.updateFromAcceptClientHintsHeader(contentAttribute->value(), nullptr);
                 }
                 return;
             }
 
             handleMetaNameAttribute(token, m_documentParameters.get(), m_mediaValues.get(), &m_cssScanner, viewport);
         }
@@ skipping 52 matching lines @@
 
     // When we start scanning, our best prediction of the baseElementURL is the real one!
     if (!startingBaseElementURL.isEmpty())
         m_scanner.setPredictedBaseElementURL(startingBaseElementURL);
 
     PreloadRequestStream requests;
 
     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, viewport);
+        bool isCSPMetaTag = false;
+        m_scanner.scan(m_token, m_source, requests, viewport, &isCSPMetaTag);
         m_token.clear();
+        // Don't preload anything if a CSP meta tag is found. We should never
+        // really find them here because the HTMLPreloadScanner is only used for
+        // dynamically added markup.
+        if (isCSPMetaTag)
+            return;
     }
 
     preloader->takeAndPreload(requests);
 }
 
 CachedDocumentParameters::CachedDocumentParameters(Document* document)
 {
     ASSERT(isMainThread());
     ASSERT(document);
     doHtmlPreloadScanning = !document->settings() || document->settings()->doHtmlPreloadScanning();
     doDocumentWritePreloadScanning = doHtmlPreloadScanning && document->frame() && document->frame()->isMainFrame();
     defaultViewportMinWidth = document->viewportDefaultMinWidth();
     viewportMetaZeroValuesQuirk = document->settings() && document->settings()->viewportMetaZeroValuesQuirk();
     viewportMetaEnabled = document->settings() && document->settings()->viewportMetaEnabled();
     referrerPolicy = document->getReferrerPolicy();
 }
 
 } // namespace blink