[superseded] Issue 1265 - Improve detection of mime type of the expected response

src/plugin/PluginWbPassThrough.cpp

 #include "PluginStdAfx.h"
 
 #include "PluginWbPassThrough.h"
 #include "PluginClient.h"
 #include "PluginClientFactory.h"
 #ifdef SUPPORT_FILTER
 #include "PluginFilter.h"
 #endif
 #include "PluginSettings.h"
 #include "PluginClass.h"
@@ skipping 173 matching lines @@
       }
       else
 #endif // SUPPORT_FRAME_CACHING
       {
         m_contentType = GetContentType(mimeType, m_boundDomain, src);
       }
     }
     
   }
 
   if (nullptr == tab)

[Oleksandr, 2014/10/01 09:15:39]

I personally don't like yoda conditions, and I think we have it in our coding
style not to use them. 

if (tab == nullptr) looks better, imho.

   {
     m_contentType = GetContentType(mimeType, m_boundDomain, src);
   }
 
   if (nullptr != client
     && CFilter::EContentType::contentTypeAny != m_contentType
     && client->ShouldBlock(src, m_contentType, m_boundDomain, true))

[Oleksandr, 2014/10/01 09:15:39]

Comment about yoda conditions applies here as well. And further below for all
the m_contentType checks.

   {
     isBlocked = true;
   }
 
   // For IE6 and earlier there is iframe back button issue, so avoid it.
   if (isBlocked && client->GetIEVersion() > 6)
   {
     handled = true;
     if (CFilter::EContentType::contentTypeImage == m_contentType)
     {
       BaseClass::OnStart(szUrl, pOIProtSink, pOIBindInfo, grfPI, dwReserved, pTargetProtocol);
       // IE shows a cross that img is not loaded
       return INET_E_REDIRECT_FAILED;
     }
     if (CFilter::EContentType::contentTypeSubdocument == m_contentType)
     {
       PassthroughAPP::CustomSinkStartPolicy<WBPassthru, WBPassthruSink>::GetProtocol(this)->m_shouldSupplyCustomContent = true;
       BaseClass::OnStart(szUrl, pOIProtSink, pOIBindInfo, grfPI, dwReserved, pTargetProtocol);
       m_spInternetProtocolSink->ReportProgress(BINDSTATUS_MIMETYPEAVAILABLE, L"text/html");
       m_spInternetProtocolSink->ReportData(BSCF_FIRSTDATANOTIFICATION, 0, static_cast<ULONG>(g_myPageBlocked.size()));
       return S_OK;
     } 
     if (CFilter::EContentType::contentTypeScript == m_contentType)
     {
       BaseClass::OnStart(szUrl, pOIProtSink, pOIBindInfo, grfPI, dwReserved, pTargetProtocol);
       m_spInternetProtocolSink->ReportProgress(BINDSTATUS_MIMETYPEAVAILABLE, L"text/javascript");
       m_spInternetProtocolSink->ReportResult(INET_E_REDIRECTING, 301, L"data:");
       return INET_E_REDIRECT_FAILED;
     }
     if (CFilter::EContentType::contentTypeXmlHttpRequest == m_contentType)

[Oleksandr, 2014/10/01 09:15:39]

Looks like we don't need a special case for contentTypeXmlHttpRequest do we? The
'if' below will do the same anyway.

+    {
+      BaseClass::OnStart(szUrl, pOIProtSink, pOIBindInfo, grfPI, dwReserved, pTargetProtocol);
+      m_spInternetProtocolSink->ReportResult(INET_E_REDIRECTING, 301, L"data:");
+      return INET_E_REDIRECT_FAILED;
+    }
+    if (CFilter::EContentType::contentTypeAny != m_contentType)
     {
       BaseClass::OnStart(szUrl, pOIProtSink, pOIBindInfo, grfPI, dwReserved, pTargetProtocol);
       m_spInternetProtocolSink->ReportResult(INET_E_REDIRECTING, 301, L"data:");

[Oleksandr, 2014/10/01 09:15:39]

I don't think redirecting all requests to 'data:' is a good idea. This should be
done only for predefined types (contentTypeObject and
contentTypeObjectSubrequest, I think). Otherwise IE might present a download
prompt to the user, if we block CSS, for example. Redirecting to
res://mshtml.dll/blank.htm is a safer option here from my experience.

       return INET_E_REDIRECT_FAILED;
     }
   }
 #endif // SUPPORT_FILTER
 
   return isBlocked ? S_FALSE : BaseClass::OnStart(szUrl, pOIProtSink, pOIBindInfo, grfPI, dwReserved, pTargetProtocol);
 }
 
 HRESULT WBPassthruSink::OnRead(void* pv, ULONG cb, ULONG* pcbRead)
 {
@@ skipping 170 matching lines @@
 }
 
 STDMETHODIMP WBPassthru::UnlockRequest()
 {
   if (m_shouldSupplyCustomContent)
   {
     return S_OK;
   }
   return PassthroughAPP::CInternetProtocol<WBStartPolicy>::UnlockRequest();
 }