Add configuration option to support additional dnsmasq flags.

config.yaml

@@ -128,6 +128,12 @@ options:
       within the cloud.  This is useful in deployments where its not
       possible to increase MTU on switches and physical servers to
       accommodate the packet overhead of using GRE tunnels.
+  dnsmasq-flags:
+    type: string
+    default:
+    description: |
+      Comma-separated list of key=value config flags with the additional
+      dhcp options for neutron dnsmasq.
   enable-l3-agent:
     type: boolean
     default: True

hooks/neutron_contexts.py

@@ -13,6 +13,7 @@ from charmhelpers.fetch import (
 from charmhelpers.contrib.openstack.context import (
     OSContextGenerator,
     NeutronAPIContext,
+    config_flags_parser
 )
 from charmhelpers.contrib.openstack.utils import (
     get_os_codename_install_source
@@ -154,6 +155,10 @@ class NeutronGatewayContext(NeutronAPIContext):
         if vlan_ranges:
             ctxt['vlan_ranges'] = ','.join(vlan_ranges.split())
 
+        dnsmasq_flags = config('dnsmasq-flags')
+        if dnsmasq_flags:
+            ctxt['dnsmasq_flags'] = config_flags_parser(dnsmasq_flags)
+
         net_dev_mtu = api_settings['network_device_mtu']
         if net_dev_mtu:
             ctxt['network_device_mtu'] = net_dev_mtu

templates/havana/dnsmasq.conf

@@ -1,3 +1,8 @@
 {%- if instance_mtu -%}
 dhcp-option=26,{{ instance_mtu }}
 {% endif -%}
+{% if dnsmasq_flags -%}
+{% for key, value in dnsmasq_flags.iteritems() -%}
+{{ key }} = {{ value }}
+{% endfor -%}
+{% endif -%}

unit_tests/test_neutron_contexts.py

@@ -123,6 +123,8 @@ class TestNeutronGatewayContext(CharmTestCase):
         self.test_config.set('debug', False)
         self.test_config.set('verbose', True)
         self.test_config.set('instance-mtu', 1420)
+        self.test_config.set('dnsmasq-flags', 'dhcp-userclass=set:ipxe,iPXE,'
+                                              'dhcp-match=set:ipxe,175')
         self.test_config.set('vlan-ranges',
                              'physnet1:1000:2000 physnet2:2001:3000')
         self.test_config.set('flat-network-providers', 'physnet3 physnet4')
@@ -152,6 +154,10 @@ class TestNeutronGatewayContext(CharmTestCase):
             'vlan_ranges': 'physnet1:1000:2000,physnet2:2001:3000',
             'network_device_mtu': 9000,
             'veth_mtu': 9000,
+            'dnsmasq_flags': {
+                'dhcp-userclass': 'set:ipxe,iPXE',
+                'dhcp-match': 'set:ipxe,175'
+            }
         })