ovsfw: Refresh OFPort when necessary

Events like server reboots change ofport numbers.  In such cases,
cached ofports need to be refreshed.

Change-Id: If4acf61736b8f1e9707efc409509e1f557d5f886
Closes-Bug: #1645655

neutron/agent/linux/openvswitch_firewall/firewall.py

@@ -243,19 +243,31 @@ class OVSFirewallDriver(firewall.FirewallDriver):
         for table in ovs_consts.OVS_FIREWALL_TABLES:
             self.int_br.br.add_flow(table=table, priority=0, actions='drop')
 
-    def get_or_create_ofport(self, port):
+    def get_ofport(self, port):
+        port_id = port['device']
+        return self.sg_port_map.ports.get(port_id)
+
+    def get_or_create_ofport(self, port):
+        """Get ofport specified by port['device'], checking and reflecting
+        ofport changes.
+        If ofport is nonexistent, create and return one.
+        """
         port_id = port['device']
-        try:
-            of_port = self.sg_port_map.ports[port_id]
-        except KeyError:
         ovs_port = self.int_br.br.get_vif_port_by_id(port_id)
         if not ovs_port:
             raise exceptions.OVSFWPortNotFound(port_id=port_id)
+
+        try:
+            of_port = self.sg_port_map.ports[port_id]
+        except KeyError:
             port_vlan_id = get_tag_from_other_config(
                 self.int_br.br, ovs_port.port_name)
             of_port = OFPort(port, ovs_port, port_vlan_id)
             self.sg_port_map.create_port(of_port, port)
         else:
+            if of_port.ofport != ovs_port.ofport:
+                self.sg_port_map.remove_port(of_port)
+                of_port = OFPort(port, ovs_port, of_port.vlan_tag)
             self.sg_port_map.update_port(of_port, port)
 
         return of_port
@@ -266,13 +278,13 @@ class OVSFirewallDriver(firewall.FirewallDriver):
     def prepare_port_filter(self, port):
         if not firewall.port_sec_enabled(port):
             return
-        port_exists = self.is_port_managed(port)
+        old_of_port = self.get_ofport(port)
         of_port = self.get_or_create_ofport(port)
-        if port_exists:
+        if old_of_port:
             LOG.error(_LE("Initializing port %s that was already "
                           "initialized."),
                       port['device'])
-            self.delete_all_port_flows(of_port)
+            self.delete_all_port_flows(old_of_port)
         self.initialize_port_flows(of_port)
         self.add_flows_from_rules(of_port)
 
@@ -289,9 +301,10 @@ class OVSFirewallDriver(firewall.FirewallDriver):
         elif not self.is_port_managed(port):
             self.prepare_port_filter(port)
             return
+        old_of_port = self.get_ofport(port)
         of_port = self.get_or_create_ofport(port)
         # TODO(jlibosva): Handle firewall blink
-        self.delete_all_port_flows(of_port)
+        self.delete_all_port_flows(old_of_port)
         self.initialize_port_flows(of_port)
         self.add_flows_from_rules(of_port)
 
@@ -303,7 +316,7 @@ class OVSFirewallDriver(firewall.FirewallDriver):
 
         """
         if self.is_port_managed(port):
-            of_port = self.get_or_create_ofport(port)
+            of_port = self.get_ofport(port)
             self.delete_all_port_flows(of_port)
             self.sg_port_map.remove_port(of_port)
 

neutron/tests/unit/agent/linux/openvswitch_firewall/test_firewall.py

@@ -30,7 +30,8 @@ TESTING_VLAN_TAG = 1
 
 
 def create_ofport(port_dict):
-    ovs_port = mock.Mock(vif_mac='00:00:00:00:00:00', port_name="port-name")
+    ovs_port = mock.Mock(vif_mac='00:00:00:00:00:00', ofport=1,
+                         port_name="port-name")
     return ovsfw.OFPort(port_dict, ovs_port, vlan_tag=TESTING_VLAN_TAG)
 
 
@@ -327,6 +328,18 @@ class TestOVSFirewallDriver(base.BaseTestCase):
         self.assertIn(port, sg1.ports)
         self.assertIn(port, sg2.ports)
 
+    def test_get_or_create_ofport_changed(self):
+        port_dict = {
+            'device': 'port-id',
+            'security_groups': [123, 456]}
+        of_port = create_ofport(port_dict)
+        self.firewall.sg_port_map.ports[of_port.id] = of_port
+        fake_ovs_port = FakeOVSPort('port', 2, '00:00:00:00:00:00')
+        self.mock_bridge.br.get_vif_port_by_id.return_value = \
+            fake_ovs_port
+        port = self.firewall.get_or_create_ofport(port_dict)
+        self.assertEqual(port.ofport, 2)
+
     def test_get_or_create_ofport_missing(self):
         port_dict = {
             'device': 'port-id',
@@ -335,6 +348,14 @@ class TestOVSFirewallDriver(base.BaseTestCase):
         with testtools.ExpectedException(exceptions.OVSFWPortNotFound):
             self.firewall.get_or_create_ofport(port_dict)
 
+    def test_get_or_create_ofport_missing_nocreate(self):
+        port_dict = {
+            'device': 'port-id',
+            'security_groups': [123, 456]}
+        self.mock_bridge.br.get_vif_port_by_id.return_value = None
+        self.assertIsNone(self.firewall.get_ofport(port_dict))
+        self.assertFalse(self.mock_bridge.br.get_vif_port_by_id.called)
+
     def test_is_port_managed_managed_port(self):
         port_dict = {'device': 'port-id'}
         self.firewall.sg_port_map.ports[port_dict['device']] = object()