PPAPI/NaCl: Restrict ppapi messages to unblock only ppapi

chrome/renderer/pepper/ppb_nacl_private_impl.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/renderer/pepper/ppb_nacl_private_impl.h"
 
 #ifndef DISABLE_NACL
 
 #if defined(OS_WIN)
 #include <fcntl.h>
 #include <io.h>
 #endif
 
 #include "base/command_line.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
 #include "base/rand_util.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/render_messages.h"
 #include "content/public/common/content_client.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/sandbox_init.h"
 #include "content/public/renderer/render_thread.h"
 #include "content/public/renderer/render_view.h"
+#include "content/public/renderer/renderer_restrict_dispatch_group.h"
 #include "ipc/ipc_sync_message_filter.h"
 #include "ppapi/c/private/ppb_nacl_private.h"
 #include "ppapi/native_client/src/trusted/plugin/nacl_entry_points.h"
 #include "ppapi/proxy/host_dispatcher.h"
 #include "ppapi/proxy/proxy_channel.h"
 #include "ppapi/shared_impl/ppapi_preferences.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebDocument.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebElement.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebFrame.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebPluginContainer.h"
@@ skipping 132 matching lines @@
 
     if (!dispatcher_->InitHostWithChannel(dispatcher_delegate_.get(),
                                           channel_handle,
                                           true,  // Client.
                                           preferences)) {
       dispatcher_.reset();
       dispatcher_delegate_.reset();
       return false;
     }
 
+    // Make sure that incoming plugin->renderer "unblock" messages can ONLY
+    // unblock other pepper messages.
+    dispatcher_->channel()->SetRestrictDispatchChannelGroup(
+        content::kRendererRestrictDispatchGroup_Pepper);
     return true;
   }
 
   // OutOfProcessProxy implementation.
   virtual const void* GetProxiedInterface(const char* name) OVERRIDE {
     return dispatcher_->GetProxiedInterface(name);
   }
   virtual void AddInstance(PP_Instance instance) OVERRIDE {
     ppapi::proxy::HostDispatcher::SetForInstance(instance, dispatcher_.get());
   }
@@ skipping 121 matching lines @@
   &GetReadonlyPnaclFD
 };
 
 }  // namespace
 
 const PPB_NaCl_Private* PPB_NaCl_Private_Impl::GetInterface() {
   return &nacl_interface;
 }
 
 #endif  // DISABLE_NACL