Added warning when setting NetVM

When NetVM is set to something else than default_dispvm has set, a warning
icon appears.

qubesmanager/settings.py

@@ -414,6 +414,8 @@ def __init_basic_tab__(self):
             (lambda vm: vm.provides_network),
             allow_default=True, allow_none=True)
 
+        self.netVM.currentIndexChanged.connect(self.check_warn_dispvmnetvm)
+
         self.include_in_backups.setChecked(self.vm.include_in_backups)
 
         try:
@@ -547,6 +549,27 @@ def check_mem_changes(self):
                         "allowed value."))
             self.init_mem.setValue(self.max_mem_size.value() / 10)
 
+    def check_warn_dispvmnetvm(self):
+        if not hasattr(self.vm, 'default_dispvm'):
+            self.warn_netvm_dispvm.setVisible(False)
+            return
+        dispvm = self.default_dispvm_list[
+            self.default_dispvm.currentIndex()]
+        own_netvm = self.netvm_list[self.netVM.currentIndex()]
+
+        if dispvm == qubesadmin.DEFAULT:
+            dispvm = self.vm.property_get_default('default_dispvm')
+        dispvm_netvm = getattr(dispvm, 'netvm', None)
+
+        if own_netvm == qubesadmin.DEFAULT:
+            own_netvm = self.vm.property_get_default('netvm')
+
+        if dispvm_netvm and dispvm_netvm != own_netvm:
+            self.warn_netvm_dispvm.setVisible(True)
+        else:
+            self.warn_netvm_dispvm.setVisible(False)
+
+
     def rename_vm(self):
 
         dependencies = admin_utils.vm_dependencies(self.vm.app, self.vm)
@@ -691,7 +714,10 @@ def __init_advanced_tab__(self):
                     None,
                     (lambda vm: getattr(vm, 'template_for_dispvms', False)),
                     allow_default=True, allow_none=True)
+            self.default_dispvm.currentIndexChanged.connect(
+                self.check_warn_dispvmnetvm)
 
+        self.check_warn_dispvmnetvm()
         self.update_virt_mode_list()
 
         windows_running = \

ui/settingsdlg.ui

@@ -29,7 +29,7 @@
         <locale language="English" country="UnitedStates"/>
        </property>
        <property name="currentIndex">
-        <number>1</number>
+        <number>0</number>
        </property>
        <widget class="QWidget" name="basic_tab">
         <property name="locale">
@@ -379,6 +379,19 @@
               </item>
              </layout>
             </item>
+            <item row="2" column="3">
+             <widget class="QLabel" name="warn_netvm_dispvm">
+              <property name="toolTip">
+               <string>&lt;html&gt;&lt;head/&gt;&lt;body&gt;&lt;p&gt;Caution: default DispVM template has a different Networking setting than this qube. Unexpected network access may occur!&lt;/p&gt;&lt;/body&gt;&lt;/html&gt;</string>
+              </property>
+              <property name="text">
+               <string/>
+              </property>
+              <property name="pixmap">
+               <pixmap resource="../resources.qrc">:/warning.png</pixmap>
+              </property>
+             </widget>
+            </item>
            </layout>
           </widget>
          </item>