Pepper: Split PpapiHostMsg_ChannelCreated use.

PpapiHostMsg_ChannelCreated is used for two purposes:
  * Notifying the browser that a browser<->plugin channel has been created, and
  * Notifying that browser that a renderer<->plugin channel has been created.

In this case renderer<->plugin channel is for NaCl-based plugins, and is
special because it does some inspection of message contents and passes on the
message to the untrusted side of the plugin.

I've changed this because I think it makes the code easier to read, and I'm
adding an additional renderer<->plugin channel anyway.

BUG=
TBR=mseaborn,jschuh

Review URL: https://codereview.chromium.org/98183012

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@243101 0039d316-1c4b-4281-b951-d872f2087c98

components/nacl/browser/nacl_process_host.cc

@@ -572,7 +572,7 @@ bool NaClProcessHost::OnMessageReceived(const IPC::Message& msg) {
                                     OnAttachDebugExceptionHandler)
 #endif
     IPC_MESSAGE_HANDLER(NaClProcessHostMsg_PpapiChannelCreated,
-                        OnPpapiChannelCreated)
+                        OnPpapiBrowserChannelCreated)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   return handled;
@@ -778,14 +778,11 @@ bool NaClProcessHost::SendStart() {
 }
 
 // This method is called when NaClProcessHostMsg_PpapiChannelCreated is
-// received or PpapiHostMsg_ChannelCreated is forwarded by our plugin
-// listener.
-void NaClProcessHost::OnPpapiChannelCreated(
+// received.
+void NaClProcessHost::OnPpapiBrowserChannelCreated(
     const IPC::ChannelHandle& channel_handle) {
   // Only renderer processes should create a channel.
   DCHECK(enable_ppapi_proxy());
-  // If the proxy channel is null, this must be the initial NaCl-Browser IPC
-  // channel.
   if (!ipc_proxy_channel_.get()) {
     DCHECK_EQ(PROCESS_TYPE_NACL_LOADER, process_->GetData().process_type);
 
@@ -833,11 +830,19 @@ void NaClProcessHost::OnPpapiChannelCreated(
             args,
             SerializedHandle(SerializedHandle::CHANNEL_HANDLE,
                              IPC::InvalidPlatformFileForTransit())));
-  } else if (reply_msg_) {
-    // Otherwise, this must be a renderer channel.
+  } else {
+    // Attempt to open more than 1 browser channel is not supported.
+    // Shut down the NaCl process.
+    process_->GetHost()->ForceShutdown();
+  }
+}
+
+void NaClProcessHost::OnPpapiRendererChannelCreated(
+    const IPC::ChannelHandle& channel_handle) {
+  if (reply_msg_) {
     ReplyToRenderer(channel_handle);
   } else {
-    // Attempt to open more than 1 renderer channel is not supported.
+    // Attempt to open more than 1 NaCl renderer channel is not supported.
     // Shut down the NaCl process.
     process_->GetHost()->ForceShutdown();
   }
@@ -848,8 +853,8 @@ bool NaClProcessHost::OnUntrustedMessageForwarded(const IPC::Message& msg) {
   // These messages come from untrusted code so should be handled with care.
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(NaClProcessHost, msg)
-    IPC_MESSAGE_HANDLER(PpapiHostMsg_ChannelCreated,
-                        OnPpapiChannelCreated)
+    IPC_MESSAGE_HANDLER(PpapiHostMsg_NaClChannelCreated,
+                        OnPpapiRendererChannelCreated)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   return handled;

components/nacl/browser/nacl_process_host.h

@@ -176,8 +176,11 @@ class NaClProcessHost : public content::BrowserChildProcessHostDelegate {
                                    IPC::Message* reply_msg);
 #endif
 
-  // Called when a PPAPI IPC channel has been created.
-  void OnPpapiChannelCreated(const IPC::ChannelHandle& channel_handle);
+  // Called when the PPAPI IPC channel to the browser has been created.
+  void OnPpapiBrowserChannelCreated(const IPC::ChannelHandle& channel_handle);
+  // Called when the PPAPI IPC channel to the renderer has been created.
+  void OnPpapiRendererChannelCreated(const IPC::ChannelHandle& channel_handle);
+
   // Called by PluginListener, so messages from the untrusted side of
   // the IPC proxy can be handled.
   bool OnUntrustedMessageForwarded(const IPC::Message& msg);

components/nacl/loader/nacl_ipc_adapter.cc

@@ -521,7 +521,7 @@ bool NaClIPCAdapter::OnMessageReceived(const IPC::Message& msg) {
           nacl_desc.reset(new NaClDescWrapper(ipc_adapter->MakeNaClDesc()));
           // Send back a message that the channel was created.
           scoped_ptr<IPC::Message> response(
-              new PpapiHostMsg_ChannelCreated(channel_handle));
+              new PpapiHostMsg_NaClChannelCreated(channel_handle));
           task_runner_->PostTask(FROM_HERE,
               base::Bind(&NaClIPCAdapter::SendMessageOnIOThread, this,
                          base::Passed(&response)));

ppapi/proxy/ppapi_messages.h

@@ -737,6 +737,8 @@ IPC_MESSAGE_CONTROL0(PpapiHostMsg_Keepalive)
 // initialize properly.
 IPC_MESSAGE_CONTROL1(PpapiHostMsg_ChannelCreated,
                      IPC::ChannelHandle /* handle */)
+IPC_MESSAGE_CONTROL1(PpapiHostMsg_NaClChannelCreated,
+                     IPC::ChannelHandle /* handle */)
 
 // Logs the given message to the console of all instances.
 IPC_MESSAGE_CONTROL4(PpapiHostMsg_LogWithSource,