NaCl: Supply Windows handle-passing function

chrome/browser/nacl_host/nacl_process_host.cc

Index: chrome/browser/nacl_host/nacl_process_host.cc
diff --git a/chrome/browser/nacl_host/nacl_process_host.cc b/chrome/browser/nacl_host/nacl_process_host.cc
index 4bf5b4078895a184b809d9f01fdbf4a64c9517bc..a804c8cf894b4b574ca15b4a2d3ffe87af71be50 100644
--- a/chrome/browser/nacl_host/nacl_process_host.cc
+++ b/chrome/browser/nacl_host/nacl_process_host.cc
@@ -50,6 +50,7 @@
 #include "base/threading/thread.h"
 #include "base/process_util.h"
 #include "chrome/browser/nacl_host/nacl_broker_service_win.h"
+#include "content/public/common/sandbox_init.h"
 #include "native_client/src/trusted/service_runtime/win/debug_exception_handler.h"
 #endif
 
@@ -918,6 +919,9 @@ bool NaClProcessHost::SendStart() {
   const ChildProcessData& data = process_->GetData();
 #if defined(OS_WIN)
   // Copy the process handle into the renderer process.
+  // TODO(mseaborn): Remove this.  The renderer process uses this
+  // handle with NaCl's handle_pass module, but we are replacing
+  // handle_pass with Chrome's BrokerDuplicateHandle() function.
   if (!DuplicateHandle(base::GetCurrentProcessHandle(),
                        data.handle,
                        chrome_render_message_filter_->peer_handle(),
@@ -928,6 +932,17 @@ bool NaClProcessHost::SendStart() {
     DLOG(ERROR) << "DuplicateHandle() failed";
     return false;
   }
+  // If we are on 64-bit Windows, the NaCl process's sandbox is
+  // managed by a different process from the renderer's sandbox.  We
+  // need to inform the renderer's sandbox about the NaCl process so
+  // that the renderer can send handles to the NaCl process using
+  // BrokerDuplicateHandle().
+  if (RunningOnWOW64()) {
+    if (!content::BrokerAddTargetPeer(data.handle)) {
+      DLOG(ERROR) << "Failed to add NaCl process PID";
+      return false;
+    }
+  }
 #else
   // We use pid as process handle on Posix
   nacl_process_handle = data.handle;