Implementation of W3C compliant CSP script-src nonce.

Source/core/dom/ScriptElement.cpp

Index: Source/core/dom/ScriptElement.cpp
diff --git a/Source/core/dom/ScriptElement.cpp b/Source/core/dom/ScriptElement.cpp
index 6b5873893dd4efd1916cd66ccff94a1ac14bf5ad..af64120139e6e0bb003cf519c26ee1635c821821 100644
--- a/Source/core/dom/ScriptElement.cpp
+++ b/Source/core/dom/ScriptElement.cpp
@@ -254,8 +254,6 @@ bool ScriptElement::requestScript(const String& sourceUrl)
         return false;
     if (!m_element->inDocument() || m_element->document() != originalDocument)
         return false;
-    if (!m_element->document()->contentSecurityPolicy()->allowScriptNonce(m_element->fastGetAttribute(HTMLNames::nonceAttr), m_element->document()->url(), m_startLineNumber, m_element->document()->completeURL(sourceUrl)))
-        return false;
 
     ASSERT(!m_cachedScript);
     if (!stripLeadingAndTrailingHTMLSpaces(sourceUrl).isEmpty()) {
@@ -270,6 +268,10 @@ bool ScriptElement::requestScript(const String& sourceUrl)
         request.setCharset(scriptCharset());
         request.setInitiator(element());
 
+        bool isValidScriptNonce = m_element->document()->contentSecurityPolicy()->allowScriptNonce(request.initiatorElement()->fastGetAttribute(HTMLNames::nonceAttr));

[abarth-chromium, 2013/05/16 21:09:16]

There's no reason to use the initiator element.  We can just use m_element. 
We're about to remove initiatorElement.

[jww, 2013/05/16 21:37:46]

Done.

+        if (isValidScriptNonce)
+            request.setContentSecurityCheck(DoNotCheckContentSecurityPolicy);
+
         m_cachedScript = m_element->document()->cachedResourceLoader()->requestScript(request);
         m_isExternalScript = true;
     }
@@ -293,10 +295,9 @@ void ScriptElement::executeScript(const ScriptSourceCode& sourceCode)
     Frame* frame = document->frame();
 
     bool shouldBypassMainWorldContentSecurityPolicy = (frame && frame->script()->shouldBypassMainWorldContentSecurityPolicy());
-    if (!shouldBypassMainWorldContentSecurityPolicy && !document->contentSecurityPolicy()->allowScriptNonce(m_element->fastGetAttribute(HTMLNames::nonceAttr), document->url(), m_startLineNumber))
-        return;
 
-    if (!m_isExternalScript && (!shouldBypassMainWorldContentSecurityPolicy && !document->contentSecurityPolicy()->allowInlineScript(document->url(), m_startLineNumber)))
+    bool isValidScriptNonce = document->contentSecurityPolicy()->allowScriptNonce(m_element->fastGetAttribute(HTMLNames::nonceAttr));
+    if (!m_isExternalScript && (!shouldBypassMainWorldContentSecurityPolicy && !(isValidScriptNonce || document->contentSecurityPolicy()->allowInlineScript(document->url(), m_startLineNumber))))

[abarth-chromium, 2013/05/16 21:09:16]

We should treat shouldBypassMainWorldContentSecurityPolicy and
isValidScriptNonce the same typographically since they're treated the same
operationally.

[jww, 2013/05/16 21:37:46]

I'm sure what you mean here. I *think* what you're saying is merge the
isValidScriptNonce check into the shouldBypassMainWorldContentSecurityPolicy
value, similar to what you suggest in a later comment. This is what I put into
the patch, so let me know if I misunderstood.
On 2013/05/16 21:09:16, abarth wrote:

         return;
 
     if (m_isExternalScript && m_cachedScript && !m_cachedScript->mimeTypeAllowedByNosniff()) {