Apply connect-src for link preload with no `as` value

third_party/WebKit/Source/core/frame/csp/ContentSecurityPolicy.cpp

 /*
  * Copyright (C) 2011 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.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 812 matching lines @@
 
   switch (context) {
     case WebURLRequest::RequestContextAudio:
     case WebURLRequest::RequestContextTrack:
     case WebURLRequest::RequestContextVideo:
       return allowMediaFromSource(url, redirectStatus, reportingStatus);
     case WebURLRequest::RequestContextBeacon:
     case WebURLRequest::RequestContextEventSource:
     case WebURLRequest::RequestContextFetch:
     case WebURLRequest::RequestContextXMLHttpRequest:
+    case WebURLRequest::RequestContextSubresource:

[Mike West, 2016/11/10 18:59:10]

How confident are you that `Subresource` is targeted to `<link rel="preload">`?
Based on
https://cs.chromium.org/chromium/src/third_party/WebKit/Source/core/fetch/Res...
it looks like other types might be effected.

       return allowConnectToSource(url, redirectStatus, reportingStatus);
     case WebURLRequest::RequestContextEmbed:
     case WebURLRequest::RequestContextObject:
       return allowObjectFromSource(url, redirectStatus, reportingStatus);
     case WebURLRequest::RequestContextFavicon:
     case WebURLRequest::RequestContextImage:
     case WebURLRequest::RequestContextImageSet:
       return allowImageFromSource(url, redirectStatus, reportingStatus);
     case WebURLRequest::RequestContextFont:
       return allowFontFromSource(url, redirectStatus, reportingStatus);
@@ skipping 18 matching lines @@
     case WebURLRequest::RequestContextStyle:
       return allowStyleFromSource(url, nonce, redirectStatus, reportingStatus);
     case WebURLRequest::RequestContextCSPReport:
     case WebURLRequest::RequestContextDownload:
     case WebURLRequest::RequestContextHyperlink:
     case WebURLRequest::RequestContextInternal:
     case WebURLRequest::RequestContextLocation:
     case WebURLRequest::RequestContextPing:
     case WebURLRequest::RequestContextPlugin:
     case WebURLRequest::RequestContextPrefetch:
-    case WebURLRequest::RequestContextSubresource:
     case WebURLRequest::RequestContextUnspecified:
       return true;
   }
   ASSERT_NOT_REACHED();
   return true;
 }
 
 void ContentSecurityPolicy::usesScriptHashAlgorithms(uint8_t algorithms) {
   m_scriptHashAlgorithmsUsed |= algorithms;
 }
@@ skipping 631 matching lines @@
   // Collisions have no security impact, so we can save space by storing only
   // the string's hash rather than the whole report.
   return !m_violationReportsSent.contains(report.impl()->hash());
 }
 
 void ContentSecurityPolicy::didSendViolationReport(const String& report) {
   m_violationReportsSent.add(report.impl()->hash());
 }
 
 }  // namespace blink