vmware-nsx/neutron/plugins/nicira/dhcp_meta/rpc.py
armando-migliaccio f1b0dbe7a7 Refactoring for nicira plugin to support NVP DHCP/Metadata services
This initial patch is aimed at decoupling core plugin services from
DHCP and metadata services. The abstraction being introduced is
needed so that the code can support both models where dhcp and
metadata services are provided by external RPC agents or solely by
the server-side plugin.

Supports blueprint nvp-dhcp-metadata-services

Change-Id: I396ee7bbcbd866e4e9d4a79887e844b4f5ec3c9e
2013-09-03 15:04:32 -07:00

246 lines
10 KiB
Python

# vim: tabstop=4 shiftwidth=4 softtabstop=4
# Copyright 2013 VMware, Inc.
# All Rights Reserved
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
#
from eventlet import greenthread
import netaddr
from oslo.config import cfg
from neutron.api.rpc.agentnotifiers import dhcp_rpc_agent_api
from neutron.api.v2 import attributes
from neutron.common import constants as const
from neutron.common import exceptions as ntn_exc
from neutron.common import rpc as n_rpc
from neutron.db import agents_db
from neutron.db import db_base_plugin_v2
from neutron.db import dhcp_rpc_base
from neutron.db import l3_db
from neutron.db import models_v2
from neutron.openstack.common import log as logging
from neutron.plugins.nicira.common import config
from neutron.plugins.nicira.common import exceptions as nvp_exc
from neutron.plugins.nicira import NvpApiClient
LOG = logging.getLogger(__name__)
METADATA_DEFAULT_PREFIX = 30
METADATA_SUBNET_CIDR = '169.254.169.252/%d' % METADATA_DEFAULT_PREFIX
METADATA_GATEWAY_IP = '169.254.169.253'
METADATA_DHCP_ROUTE = '169.254.169.254/32'
class NVPRpcCallbacks(dhcp_rpc_base.DhcpRpcCallbackMixin):
RPC_API_VERSION = '1.1'
def create_rpc_dispatcher(self):
'''Get the rpc dispatcher for this manager.
If a manager would like to set an rpc API version, or support more than
one class as the target of rpc messages, override this method.
'''
return n_rpc.PluginRpcDispatcher([self,
agents_db.AgentExtRpcCallback()])
def handle_network_dhcp_access(plugin, context, network, action):
# TODO(armando-migliaccio): revise the implementation of this
# method in the context bug #1212555; a potential fix might be
# as simple as a 'pass', but keeping the hook might be useful
# in other agent modes.
if action == 'create_network':
plugin.schedule_network(context, network)
def handle_port_dhcp_access(plugin, context, port_data, action):
if action == 'create_port':
net = plugin.get_network(context, port_data['network_id'])
plugin.schedule_network(context, net)
active_port = (cfg.CONF.NVP.metadata_mode == config.MetadataModes.INDIRECT
and port_data.get('device_owner') == const.DEVICE_OWNER_DHCP
and port_data.get('fixed_ips', []))
if active_port:
subnet_id = port_data['fixed_ips'][0]['subnet_id']
subnet = plugin.get_subnet(context, subnet_id)
if (cfg.CONF.dhcp_agent_notification and subnet.get('gateway_ip')
or action == 'delete_port'):
dhcp_notifier = dhcp_rpc_agent_api.DhcpAgentNotifyAPI()
dhcp_notifier.notify(
context, {'subnet': subnet}, 'subnet.update.end')
def handle_port_metadata_access(context, port, is_delete=False):
if (cfg.CONF.NVP.metadata_mode == config.MetadataModes.INDIRECT and
port.get('device_owner') == const.DEVICE_OWNER_DHCP):
if port.get('fixed_ips', []) or is_delete:
fixed_ip = port['fixed_ips'][0]
query = context.session.query(models_v2.Subnet)
subnet = query.filter(
models_v2.Subnet.id == fixed_ip['subnet_id']).one()
# If subnet does not have a gateway do not create metadata
# route. This is done via the enable_isolated_metadata
# option if desired.
if not subnet.get('gateway_ip'):
return
metadata_routes = [r for r in subnet.routes
if r['destination'] == METADATA_DHCP_ROUTE]
if metadata_routes:
# We should have only a single metadata route at any time
# because the route logic forbids two routes with the same
# destination. Update next hop with the provided IP address
if not is_delete:
metadata_routes[0].nexthop = fixed_ip['ip_address']
else:
context.session.delete(metadata_routes[0])
else:
# add the metadata route
route = models_v2.SubnetRoute(
subnet_id=subnet.id,
destination=METADATA_DHCP_ROUTE,
nexthop=fixed_ip['ip_address'])
context.session.add(route)
def handle_router_metadata_access(plugin, context, router_id, do_create=True):
if cfg.CONF.NVP.metadata_mode != config.MetadataModes.DIRECT:
LOG.debug(_("Metadata access network is disabled"))
return
if not cfg.CONF.allow_overlapping_ips:
LOG.warn(_("Overlapping IPs must be enabled in order to setup "
"the metadata access network"))
return
# As we'll use a different device_owner for metadata interface
# this query will return only 'real' router interfaces
ctx_elevated = context.elevated()
device_filter = {'device_id': [router_id],
'device_owner': [l3_db.DEVICE_OWNER_ROUTER_INTF]}
# Retrieve ports calling database plugin
ports = db_base_plugin_v2.NeutronDbPluginV2.get_ports(
plugin, context, filters=device_filter)
try:
if ports:
if (do_create and
not _find_metadata_port(plugin, ctx_elevated, ports)):
_create_metadata_access_network(
plugin, ctx_elevated, router_id)
elif len(ports) == 1:
# The only port left might be the metadata port
_destroy_metadata_access_network(
plugin, ctx_elevated, router_id, ports)
else:
LOG.debug(_("No router interface found for router '%s'. "
"No metadata access network should be "
"created or destroyed"), router_id)
# TODO(salvatore-orlando): A better exception handling in the
# NVP plugin would allow us to improve error handling here
except (ntn_exc.NeutronException, nvp_exc.NvpPluginException,
NvpApiClient.NvpApiException):
# Any exception here should be regarded as non-fatal
LOG.exception(_("An error occurred while operating on the "
"metadata access network for router:'%s'"),
router_id)
def _find_metadata_port(plugin, context, ports):
for port in ports:
for fixed_ip in port['fixed_ips']:
cidr = netaddr.IPNetwork(
plugin.get_subnet(context, fixed_ip['subnet_id'])['cidr'])
if cidr in netaddr.IPNetwork(METADATA_SUBNET_CIDR):
return port
def _create_metadata_access_network(plugin, context, router_id):
# Add network
# Network name is likely to be truncated on NVP
net_data = {'name': 'meta-%s' % router_id,
'tenant_id': '', # intentionally not set
'admin_state_up': True,
'port_security_enabled': False,
'shared': False,
'status': const.NET_STATUS_ACTIVE}
meta_net = plugin.create_network(context,
{'network': net_data})
greenthread.sleep(0) # yield
# From this point on there will be resources to garbage-collect
# in case of failures
meta_sub = None
try:
# Add subnet
subnet_data = {'network_id': meta_net['id'],
'tenant_id': '', # intentionally not set
'name': 'meta-%s' % router_id,
'ip_version': 4,
'shared': False,
'cidr': METADATA_SUBNET_CIDR,
'enable_dhcp': True,
# Ensure default allocation pool is generated
'allocation_pools': attributes.ATTR_NOT_SPECIFIED,
'gateway_ip': METADATA_GATEWAY_IP,
'dns_nameservers': [],
'host_routes': []}
meta_sub = plugin.create_subnet(context,
{'subnet': subnet_data})
greenthread.sleep(0) # yield
plugin.add_router_interface(context, router_id,
{'subnet_id': meta_sub['id']})
greenthread.sleep(0) # yield
except (ntn_exc.NeutronException,
nvp_exc.NvpPluginException,
NvpApiClient.NvpApiException):
# It is not necessary to explicitly delete the subnet
# as it will be removed with the network
plugin.delete_network(context, meta_net['id'])
if cfg.CONF.dhcp_agent_notification:
# We need to send a notification to the dhcp agent in
# order to start the metadata agent proxy
dhcp_notifier = dhcp_rpc_agent_api.DhcpAgentNotifyAPI()
dhcp_notifier.notify(context, {'network': meta_net},
'network.create.end')
def _destroy_metadata_access_network(plugin, context, router_id, ports):
if not ports:
return
meta_port = _find_metadata_port(plugin, context, ports)
if not meta_port:
return
meta_net_id = meta_port['network_id']
meta_sub_id = meta_port['fixed_ips'][0]['subnet_id']
plugin.remove_router_interface(
context, router_id, {'port_id': meta_port['id']})
greenthread.sleep(0) # yield
try:
# Remove network (this will remove the subnet too)
plugin.delete_network(context, meta_net_id)
greenthread.sleep(0) # yield
except (ntn_exc.NeutronException, nvp_exc.NvpPluginException,
NvpApiClient.NvpApiException):
# must re-add the router interface
plugin.add_router_interface(context, router_id,
{'subnet_id': meta_sub_id})
if cfg.CONF.dhcp_agent_notification:
# We need to send a notification to the dhcp agent in
# order to stop the metadata agent proxy
dhcp_notifier = dhcp_rpc_agent_api.DhcpAgentNotifyAPI()
dhcp_notifier.notify(context,
{'network': {'id': meta_net_id}},
'network.delete.end')