bundles/powerdns: add iptables config

bundles/powerdns/metadata.py

@@ -165,3 +165,17 @@ def hosts_entries_for_all_dns_servers(metadata):
             'entries': entries,
         },
     }
+
+
+@metadata_reactor.provides(
+    'iptables/port_rules',
+)
+def iptables(metadata):
+    return {
+        'iptables': {
+            'port_rules': {
+                '53': atomic(metadata.get('powerdns/restrict-to', set('*'))),
+                '53/udp': atomic(metadata.get('powerdns/restrict-to', set('*'))),
+            },
+        },
+    }