Merge "Fix enable_metadata_network flag"

neutron/agent/dhcp_agent.py

@@ -20,7 +20,6 @@ import sys
 import eventlet
 eventlet.monkey_patch()
 
-import netaddr
 from oslo.config import cfg
 from oslo import messaging
 from oslo.utils import importutils
@@ -355,10 +354,9 @@ class DhcpAgent(manager.Manager):
         # or all the networks connected via a router
         # to the one passed as a parameter
         neutron_lookup_param = '--network_id=%s' % network.id
-        meta_cidr = netaddr.IPNetwork(dhcp.METADATA_DEFAULT_CIDR)
+        # When the metadata network is enabled, the proxy might
-        has_metadata_subnet = any(netaddr.IPNetwork(s.cidr) in meta_cidr
+        # be started for the router attached to the network
-                                  for s in network.subnets)
+        if self.conf.enable_metadata_network:
-        if (self.conf.enable_metadata_network and has_metadata_subnet):
             router_ports = [port for port in network.ports
                             if (port.device_owner ==
                                 constants.DEVICE_OWNER_ROUTER_INTF)]

neutron/agent/linux/dhcp.py

@@ -747,8 +747,25 @@ class Dnsmasq(DhcpLocalProcess):
 
     @classmethod
     def should_enable_metadata(cls, conf, network):
-        """True if there exists a subnet for which a metadata proxy is needed
+        """Determine whether the metadata proxy is needed for a network
+
+        This method returns True for truly isolated networks (ie: not attached
+        to a router), when the enable_isolated_metadata flag is True.
+
+        This method also returns True when enable_metadata_network is True,
+        and the network passed as a parameter has a subnet in the link-local
+        CIDR, thus characterizing it as a "metadata" network. The metadata
+        network is used by solutions which do not leverage the l3 agent for
+        providing access to the metadata service via logical routers built
+        with 3rd party backends.
         """
+        if conf.enable_metadata_network and conf.enable_isolated_metadata:
+            # check if the network has a metadata subnet
+            meta_cidr = netaddr.IPNetwork(METADATA_DEFAULT_CIDR)
+            if any(netaddr.IPNetwork(s.cidr) in meta_cidr
+                   for s in network.subnets):
+                return True
+
         if not conf.use_namespaces or not conf.enable_isolated_metadata:
             return False
 

neutron/tests/unit/test_linux_dhcp.py

@@ -126,13 +126,14 @@ class FakeRouterPort:
     id = 'rrrrrrrr-rrrr-rrrr-rrrr-rrrrrrrrrrrr'
     admin_state_up = True
     device_owner = constants.DEVICE_OWNER_ROUTER_INTF
-    fixed_ips = [FakeIPAllocation('192.168.0.1',
-                                  'dddddddd-dddd-dddd-dddd-dddddddddddd')]
     mac_address = '00:00:0f:rr:rr:rr'
 
-    def __init__(self, dev_owner=constants.DEVICE_OWNER_ROUTER_INTF):
+    def __init__(self, dev_owner=constants.DEVICE_OWNER_ROUTER_INTF,
+                 ip_address='192.168.0.1'):
         self.extra_dhcp_opts = []
         self.device_owner = dev_owner
+        self.fixed_ips = [FakeIPAllocation(
+            ip_address, 'dddddddd-dddd-dddd-dddd-dddddddddddd')]
 
 
 class FakePortMultipleAgents1:
@@ -184,6 +185,16 @@ class FakeV4Subnet:
     dns_nameservers = ['8.8.8.8']
 
 
+class FakeV4MetadataSubnet:
+    id = 'dddddddd-dddd-dddd-dddd-dddddddddddd'
+    ip_version = 4
+    cidr = '169.254.169.254/30'
+    gateway_ip = '169.254.169.253'
+    enable_dhcp = True
+    host_routes = []
+    dns_nameservers = []
+
+
 class FakeV4SubnetGatewayRoute:
     id = 'dddddddd-dddd-dddd-dddd-dddddddddddd'
     ip_version = 4
@@ -342,6 +353,12 @@ class FakeV4NetworkNoRouter:
     ports = [FakePort1()]
 
 
+class FakeV4MetadataNetwork:
+    id = 'cccccccc-cccc-cccc-cccc-cccccccccccc'
+    subnets = [FakeV4MetadataSubnet()]
+    ports = [FakeRouterPort(ip_address='169.254.169.253')]
+
+
 class FakeV4NetworkDistRouter:
     id = 'cccccccc-cccc-cccc-cccc-cccccccccccc'
     subnets = [FakeV4Subnet()]
@@ -477,13 +494,15 @@ class TestBase(base.BaseTestCase):
         self.conf.register_opts(base_config.core_opts)
         self.conf.register_opts(dhcp.OPTS)
         config.register_interface_driver_opts_helper(self.conf)
+        config.register_use_namespaces_opts_helper(self.conf)
         instance = mock.patch("neutron.agent.linux.dhcp.DeviceManager")
         self.mock_mgr = instance.start()
         self.conf.register_opt(cfg.BoolOpt('enable_isolated_metadata',
                                            default=True))
+        self.conf.register_opt(cfg.BoolOpt('enable_metadata_network',
+                                           default=False))
         self.config_parse(self.conf)
         self.conf.set_override('state_path', '')
-        self.conf.use_namespaces = True
 
         self.replace_p = mock.patch('neutron.agent.linux.utils.replace_file')
         self.execute_p = mock.patch('neutron.agent.linux.utils.execute')
@@ -1371,3 +1390,26 @@ tag:tag0,option:router""".lstrip()
         dm._output_hosts_file()
         self.safe.assert_has_calls([mock.call(exp_host_name,
                                               exp_host_data)])
+
+    def test_should_enable_metadata_namespaces_disabled_returns_false(self):
+        self.conf.set_override('use_namespaces', False)
+        self.assertFalse(dhcp.Dnsmasq.should_enable_metadata(self.conf,
+                                                             mock.ANY))
+
+    def test_should_enable_metadata_isolated_network_returns_true(self):
+        self.assertTrue(dhcp.Dnsmasq.should_enable_metadata(
+            self.conf, FakeV4NetworkNoRouter()))
+
+    def test_should_enable_metadata_non_isolated_network_returns_false(self):
+        self.assertFalse(dhcp.Dnsmasq.should_enable_metadata(
+            self.conf, FakeV4NetworkDistRouter()))
+
+    def test_should_enable_metadata_isolated_meta_disabled_returns_false(self):
+        self.conf.set_override('enable_isolated_metadata', False)
+        self.assertFalse(dhcp.Dnsmasq.should_enable_metadata(self.conf,
+                                                             mock.ANY))
+
+    def test_should_enable_metadata_with_metadata_network_returns_true(self):
+        self.conf.set_override('enable_metadata_network', True)
+        self.assertTrue(dhcp.Dnsmasq.should_enable_metadata(
+            self.conf, FakeV4MetadataNetwork()))