xace: add creation hook for new input devices.

Unfortunately, more information is needed to properly label the device.
This will come from the configuration file, the hotplug messages, etc.
It will either have to be passed into this function,
or this hook moved down into the callers.

dix/devices.c

@@ -119,7 +119,6 @@ AddInputDevice(DeviceProc deviceProc, Bool autoStart)
     dev->name = (char *)NULL;
     dev->type = 0;
     dev->id = devid;
-    inputInfo.numDevices++;
     dev->public.on = FALSE;
     dev->public.processInputProc = (ProcessInputProc)NoopDDA;
     dev->public.realInputProc = (ProcessInputProc)NoopDDA;
@@ -156,6 +155,15 @@ AddInputDevice(DeviceProc deviceProc, Bool autoStart)
     dev->inited = FALSE;
     dev->enabled = FALSE;
 
+    /*  security creation/labeling check
+     */
+    if (XaceHook(XACE_DEVICE_ACCESS, serverClient, dev, DixCreateAccess)) {
+	xfree(dev);
+	return NULL;
+    }
+
+    inputInfo.numDevices++;
+
     for (prev = &inputInfo.off_devices; *prev; prev = &(*prev)->next)
         ;
     *prev = dev;