ipc: Allow attachment brokering for shared memory handles.

ipc/attachment_broker_privileged_win.cc

 // Copyright 2015 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 "ipc/attachment_broker_privileged_win.h"
 
 #include <windows.h>
 
 #include "base/process/process.h"
 #include "ipc/attachment_broker_messages.h"
 #include "ipc/brokerable_attachment.h"
 #include "ipc/handle_attachment_win.h"
 #include "ipc/ipc_channel.h"
 
 namespace IPC {
 
 AttachmentBrokerPrivilegedWin::AttachmentBrokerPrivilegedWin() {}
 
 AttachmentBrokerPrivilegedWin::~AttachmentBrokerPrivilegedWin() {}
 
 bool AttachmentBrokerPrivilegedWin::SendAttachmentToProcess(
     const scoped_refptr<IPC::BrokerableAttachment>& attachment,
     base::ProcessId destination_process) {
   switch (attachment->GetBrokerableType()) {
     case BrokerableAttachment::WIN_HANDLE: {
-      const internal::HandleAttachmentWin* handle_attachment =
-          static_cast<const internal::HandleAttachmentWin*>(attachment.get());
+      internal::HandleAttachmentWin* handle_attachment =
+          static_cast<internal::HandleAttachmentWin*>(attachment.get());
       HandleWireFormat wire_format =
           handle_attachment->GetWireFormat(destination_process);
       HandleWireFormat new_wire_format =
           DuplicateWinHandle(wire_format, base::Process::Current().Pid());
+      handle_attachment->reset_handle_ownership();
       if (new_wire_format.handle == 0)
         return false;
       RouteDuplicatedHandle(new_wire_format);
       return true;
     }
     case BrokerableAttachment::MACH_PORT:
     case BrokerableAttachment::PLACEHOLDER:
       NOTREACHED();
       return false;
   }
@@ skipping 58 matching lines @@
 
 AttachmentBrokerPrivilegedWin::HandleWireFormat
 AttachmentBrokerPrivilegedWin::DuplicateWinHandle(
     const HandleWireFormat& wire_format,
     base::ProcessId source_pid) {
   // If the source process is the destination process, then no additional work
   // is required.
   if (source_pid == wire_format.destination_process)
     return wire_format;
 
+  // If the handle is not valid, no additional work is required.
+  if (wire_format.handle == 0)
+    return wire_format;
+
   base::Process source_process =
       base::Process::OpenWithExtraPrivileges(source_pid);
   base::Process dest_process =
       base::Process::OpenWithExtraPrivileges(wire_format.destination_process);
   if (!source_process.Handle() || !dest_process.Handle()) {
     LogError(ERROR_COULD_NOT_OPEN_SOURCE_OR_DEST);
     return wire_format;
   }
 
   DWORD desired_access = 0;
@@ skipping 22 matching lines @@
 
 AttachmentBrokerPrivilegedWin::HandleWireFormat
 AttachmentBrokerPrivilegedWin::CopyWireFormat(
     const HandleWireFormat& wire_format,
     int handle) {
   return HandleWireFormat(handle, wire_format.destination_process,
                           wire_format.permissions, wire_format.attachment_id);
 }
 
 }  // namespace IPC