vmware-nsx/quantum/agent/l3_agent.py

559 lines
23 KiB
Python

"""
# vim: tabstop=4 shiftwidth=4 softtabstop=4
#
# Copyright 2012 Nicira Networks, 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.
#
# @author: Dan Wendlandt, Nicira, Inc
#
"""
import sys
import time
import netaddr
from quantum.agent.common import config
from quantum.agent.linux import interface
from quantum.agent.linux import ip_lib
from quantum.agent.linux import iptables_manager
from quantum.agent.linux import utils
from quantum.db import l3_db
from quantum.openstack.common import cfg
from quantum.openstack.common import importutils
from quantum.openstack.common import log as logging
from quantumclient.v2_0 import client
LOG = logging.getLogger(__name__)
NS_PREFIX = 'qrouter-'
INTERNAL_DEV_PREFIX = 'qr-'
EXTERNAL_DEV_PREFIX = 'qg-'
class RouterInfo(object):
def __init__(self, router_id, root_helper, use_namespaces):
self.router_id = router_id
self.ex_gw_port = None
self.internal_ports = []
self.floating_ips = []
self.root_helper = root_helper
self.use_namespaces = use_namespaces
self.iptables_manager = iptables_manager.IptablesManager(
root_helper=root_helper,
#FIXME(danwent): use_ipv6=True,
namespace=self.ns_name())
def ns_name(self):
if self.use_namespaces:
return NS_PREFIX + self.router_id
class L3NATAgent(object):
OPTS = [
cfg.StrOpt('admin_user'),
cfg.StrOpt('admin_password'),
cfg.StrOpt('admin_tenant_name'),
cfg.StrOpt('auth_url'),
cfg.StrOpt('auth_strategy', default='keystone'),
cfg.StrOpt('auth_region'),
cfg.StrOpt('root_helper', default='sudo'),
cfg.StrOpt('external_network_bridge', default='br-ex',
help="Name of bridge used for external network traffic."),
cfg.StrOpt('interface_driver',
help="The driver used to manage the virtual interface."),
cfg.IntOpt('polling_interval',
default=3,
help="The time in seconds between state poll requests."),
cfg.StrOpt('metadata_ip', default='',
help="IP address used by Nova metadata server."),
cfg.IntOpt('metadata_port',
default=8775,
help="TCP Port used by Nova metadata server."),
cfg.IntOpt('send_arp_for_ha',
default=3,
help="Send this many gratuitous ARPs for HA setup, "
"set it below or equal to 0 to disable this feature."),
cfg.BoolOpt('use_namespaces', default=True,
help="Allow overlapping IP."),
cfg.StrOpt('router_id', default='',
help="If namespaces is disabled, the l3 agent can only"
" confgure a router that has the matching router ID."),
cfg.BoolOpt('handle_internal_only_routers',
default=True,
help="Agent should implement routers with no gateway"),
cfg.StrOpt('gateway_external_network_id', default='',
help="UUID of external network for routers implemented "
"by the agents."),
]
def __init__(self, conf):
self.conf = conf
self.router_info = {}
if not conf.interface_driver:
LOG.error(_('You must specify an interface driver'))
sys.exit(1)
try:
self.driver = importutils.import_object(conf.interface_driver,
conf)
except:
LOG.exception(_("Error importing interface driver '%s'"
% conf.interface_driver))
sys.exit(1)
self.polling_interval = conf.polling_interval
self.qclient = client.Client(
username=self.conf.admin_user,
password=self.conf.admin_password,
tenant_name=self.conf.admin_tenant_name,
auth_url=self.conf.auth_url,
auth_strategy=self.conf.auth_strategy,
auth_region=self.conf.auth_region
)
if self.conf.use_namespaces:
self._destroy_all_router_namespaces()
def _destroy_all_router_namespaces(self):
"""Destroy all router namespaces on the host to eliminate
all stale linux devices, iptables rules, and namespaces.
"""
root_ip = ip_lib.IPWrapper(self.conf.root_helper)
for ns in root_ip.get_namespaces(self.conf.root_helper):
if ns.startswith(NS_PREFIX):
try:
self._destroy_router_namespace(ns)
except:
LOG.exception("couldn't delete namespace '%s'" % ns)
def _destroy_router_namespace(self, namespace):
ns_ip = ip_lib.IPWrapper(self.conf.root_helper,
namespace=namespace)
for d in ns_ip.get_devices(exclude_loopback=True):
if d.name.startswith(INTERNAL_DEV_PREFIX):
# device is on default bridge
self.driver.unplug(d.name, namespace=namespace,
prefix=INTERNAL_DEV_PREFIX)
elif d.name.startswith(EXTERNAL_DEV_PREFIX):
self.driver.unplug(d.name,
bridge=self.conf.external_network_bridge,
namespace=namespace,
prefix=EXTERNAL_DEV_PREFIX)
#(TODO) Address the failure for the deletion of the namespace
def _create_router_namespace(self, ri):
ip_wrapper_root = ip_lib.IPWrapper(self.conf.root_helper)
ip_wrapper = ip_wrapper_root.ensure_namespace(ri.ns_name())
ip_wrapper.netns.execute(['sysctl', '-w', 'net.ipv4.ip_forward=1'])
def daemon_loop(self):
#TODO(danwent): this simple diff logic does not handle if
# details of a router port (e.g., IP, mac) are changed behind
# our back. Will fix this properly with update notifications.
while True:
try:
self.do_single_loop()
except:
LOG.exception("Error running l3_nat daemon_loop")
time.sleep(self.polling_interval)
def _fetch_external_net_id(self):
"""Find UUID of single external network for this agent"""
if self.conf.gateway_external_network_id:
return self.conf.gateway_external_network_id
params = {'router:external': True}
ex_nets = self.qclient.list_networks(**params)['networks']
if len(ex_nets) > 1:
raise Exception("must configure 'gateway_external_network_id' if "
"Quantum has more than one external network.")
if len(ex_nets) == 0:
return None
return ex_nets[0]['id']
def do_single_loop(self):
if (self.conf.external_network_bridge and
not ip_lib.device_exists(self.conf.external_network_bridge)):
LOG.error("external network bridge '%s' does not exist"
% self.conf.external_network_bridge)
return
prev_router_ids = set(self.router_info)
cur_router_ids = set()
target_ex_net_id = self._fetch_external_net_id()
# identify and update new or modified routers
for r in self.qclient.list_routers()['routers']:
if not r['admin_state_up']:
continue
ex_net_id = (r['external_gateway_info'] and
r['external_gateway_info'].get('network_id'))
if not ex_net_id and not self.conf.handle_internal_only_routers:
continue
if ex_net_id and ex_net_id != target_ex_net_id:
continue
# If namespaces are disabled, only process the router associated
# with the configured agent id.
if (self.conf.use_namespaces or
r['id'] == self.conf.router_id):
cur_router_ids.add(r['id'])
else:
continue
if r['id'] not in self.router_info:
self._router_added(r['id'])
ri = self.router_info[r['id']]
self.process_router(ri)
# identify and remove routers that no longer exist
for router_id in prev_router_ids - cur_router_ids:
self._router_removed(router_id)
prev_router_ids = cur_router_ids
def _router_added(self, router_id):
ri = RouterInfo(router_id, self.conf.root_helper,
self.conf.use_namespaces)
self.router_info[router_id] = ri
if self.conf.use_namespaces:
self._create_router_namespace(ri)
for c, r in self.metadata_filter_rules():
ri.iptables_manager.ipv4['filter'].add_rule(c, r)
for c, r in self.metadata_nat_rules():
ri.iptables_manager.ipv4['nat'].add_rule(c, r)
ri.iptables_manager.apply()
def _router_removed(self, router_id):
ri = self.router_info[router_id]
for c, r in self.metadata_filter_rules():
ri.iptables_manager.ipv4['filter'].remove_rule(c, r)
for c, r in self.metadata_nat_rules():
ri.iptables_manager.ipv4['nat'].remove_rule(c, r)
ri.iptables_manager.apply()
del self.router_info[router_id]
self._destroy_router_namespace(ri.ns_name())
def _set_subnet_info(self, port):
ips = port['fixed_ips']
if not ips:
raise Exception("Router port %s has no IP address" % port['id'])
if len(ips) > 1:
LOG.error("Ignoring multiple IPs on router port %s" % port['id'])
port['subnet'] = self.qclient.show_subnet(
ips[0]['subnet_id'])['subnet']
prefixlen = netaddr.IPNetwork(port['subnet']['cidr']).prefixlen
port['ip_cidr'] = "%s/%s" % (ips[0]['ip_address'], prefixlen)
def process_router(self, ri):
ex_gw_port = self._get_ex_gw_port(ri)
internal_ports = self.qclient.list_ports(
device_id=ri.router_id,
device_owner=l3_db.DEVICE_OWNER_ROUTER_INTF)['ports']
existing_port_ids = set([p['id'] for p in ri.internal_ports])
current_port_ids = set([p['id'] for p in internal_ports
if p['admin_state_up']])
new_ports = [p for p in internal_ports if
p['id'] in current_port_ids and
p['id'] not in existing_port_ids]
old_ports = [p for p in ri.internal_ports if
p['id'] not in current_port_ids]
for p in new_ports:
self._set_subnet_info(p)
ri.internal_ports.append(p)
self.internal_network_added(ri, ex_gw_port,
p['network_id'], p['id'],
p['ip_cidr'], p['mac_address'])
for p in old_ports:
ri.internal_ports.remove(p)
self.internal_network_removed(ri, ex_gw_port, p['id'],
p['ip_cidr'])
internal_cidrs = [p['ip_cidr'] for p in ri.internal_ports]
if ex_gw_port and not ri.ex_gw_port:
self._set_subnet_info(ex_gw_port)
self.external_gateway_added(ri, ex_gw_port, internal_cidrs)
elif not ex_gw_port and ri.ex_gw_port:
self.external_gateway_removed(ri, ri.ex_gw_port,
internal_cidrs)
if ri.ex_gw_port or ex_gw_port:
self.process_router_floating_ips(ri, ex_gw_port)
ri.ex_gw_port = ex_gw_port
def process_router_floating_ips(self, ri, ex_gw_port):
floating_ips = self.qclient.list_floatingips(
router_id=ri.router_id)['floatingips']
existing_floating_ip_ids = set([fip['id'] for fip in ri.floating_ips])
cur_floating_ip_ids = set([fip['id'] for fip in floating_ips])
id_to_fixed_map = {}
for fip in floating_ips:
if fip['port_id']:
if fip['id'] not in existing_floating_ip_ids:
ri.floating_ips.append(fip)
self.floating_ip_added(ri, ex_gw_port,
fip['floating_ip_address'],
fip['fixed_ip_address'])
# store to see if floatingip was remapped
id_to_fixed_map[fip['id']] = fip['fixed_ip_address']
floating_ip_ids_to_remove = (existing_floating_ip_ids -
cur_floating_ip_ids)
for fip in ri.floating_ips:
if fip['id'] in floating_ip_ids_to_remove:
ri.floating_ips.remove(fip)
self.floating_ip_removed(ri, ri.ex_gw_port,
fip['floating_ip_address'],
fip['fixed_ip_address'])
else:
# handle remapping of a floating IP
cur_fixed_ip = id_to_fixed_map[fip['id']]
existing_fixed_ip = fip['fixed_ip_address']
if (cur_fixed_ip and existing_fixed_ip and
cur_fixed_ip != existing_fixed_ip):
floating_ip = fip['floating_ip_address']
self.floating_ip_removed(ri, ri.ex_gw_port,
floating_ip, existing_fixed_ip)
self.floating_ip_added(ri, ri.ex_gw_port,
floating_ip, cur_fixed_ip)
def _get_ex_gw_port(self, ri):
ports = self.qclient.list_ports(
device_id=ri.router_id,
device_owner=l3_db.DEVICE_OWNER_ROUTER_GW)['ports']
if not ports:
return None
elif len(ports) == 1:
return ports[0]
else:
LOG.error("Ignoring multiple gateway ports for router %s"
% ri.router_id)
def _send_gratuitous_arp_packet(self, ri, interface_name, ip_address):
if self.conf.send_arp_for_ha > 0:
arping_cmd = ['arping', '-A', '-U',
'-I', interface_name,
'-c', self.conf.send_arp_for_ha,
ip_address]
try:
if self.conf.use_namespaces:
ip_wrapper = ip_lib.IPWrapper(self.conf.root_helper,
namespace=ri.ns_name())
ip_wrapper.netns.execute(arping_cmd, check_exit_code=True)
else:
utils.execute(arping_cmd, check_exit_code=True,
root_helper=self.conf.root_helper)
except Exception as e:
LOG.error(_("Failed sending gratuitous ARP: %s") % str(e))
def get_internal_device_name(self, port_id):
return (INTERNAL_DEV_PREFIX + port_id)[:self.driver.DEV_NAME_LEN]
def get_external_device_name(self, port_id):
return (EXTERNAL_DEV_PREFIX + port_id)[:self.driver.DEV_NAME_LEN]
def external_gateway_added(self, ri, ex_gw_port, internal_cidrs):
interface_name = self.get_external_device_name(ex_gw_port['id'])
ex_gw_ip = ex_gw_port['fixed_ips'][0]['ip_address']
if not ip_lib.device_exists(interface_name,
root_helper=self.conf.root_helper,
namespace=ri.ns_name()):
self.driver.plug(ex_gw_port['network_id'],
ex_gw_port['id'], interface_name,
ex_gw_port['mac_address'],
bridge=self.conf.external_network_bridge,
namespace=ri.ns_name(),
prefix=EXTERNAL_DEV_PREFIX)
self.driver.init_l3(interface_name, [ex_gw_port['ip_cidr']],
namespace=ri.ns_name())
ip_address = ex_gw_port['ip_cidr'].split('/')[0]
self._send_gratuitous_arp_packet(ri, interface_name, ip_address)
gw_ip = ex_gw_port['subnet']['gateway_ip']
if ex_gw_port['subnet']['gateway_ip']:
cmd = ['route', 'add', 'default', 'gw', gw_ip]
if self.conf.use_namespaces:
ip_wrapper = ip_lib.IPWrapper(self.conf.root_helper,
namespace=ri.ns_name())
ip_wrapper.netns.execute(cmd, check_exit_code=False)
else:
utils.execute(cmd, check_exit_code=False,
root_helper=self.conf.root_helper)
for (c, r) in self.external_gateway_nat_rules(ex_gw_ip,
internal_cidrs,
interface_name):
ri.iptables_manager.ipv4['nat'].add_rule(c, r)
ri.iptables_manager.apply()
def external_gateway_removed(self, ri, ex_gw_port, internal_cidrs):
interface_name = self.get_external_device_name(ex_gw_port['id'])
if ip_lib.device_exists(interface_name,
root_helper=self.conf.root_helper,
namespace=ri.ns_name()):
self.driver.unplug(interface_name,
bridge=self.conf.external_network_bridge,
namespace=ri.ns_name(),
prefix=EXTERNAL_DEV_PREFIX)
ex_gw_ip = ex_gw_port['fixed_ips'][0]['ip_address']
for c, r in self.external_gateway_nat_rules(ex_gw_ip, internal_cidrs,
interface_name):
ri.iptables_manager.ipv4['nat'].remove_rule(c, r)
ri.iptables_manager.apply()
def metadata_filter_rules(self):
rules = []
if self.conf.metadata_ip:
rules.append(('INPUT', '-s 0.0.0.0/0 -d %s '
'-p tcp -m tcp --dport %s '
'-j ACCEPT' %
(self.conf.metadata_ip, self.conf.metadata_port)))
return rules
def metadata_nat_rules(self):
rules = []
if self.conf.metadata_ip:
rules.append(('PREROUTING', '-s 0.0.0.0/0 -d 169.254.169.254/32 '
'-p tcp -m tcp --dport 80 -j DNAT '
'--to-destination %s:%s' %
(self.conf.metadata_ip, self.conf.metadata_port)))
return rules
def external_gateway_nat_rules(self, ex_gw_ip, internal_cidrs,
interface_name):
rules = [('POSTROUTING', '! -i %(interface_name)s '
'! -o %(interface_name)s -m conntrack ! '
'--ctstate DNAT -j ACCEPT' % locals())]
for cidr in internal_cidrs:
rules.extend(self.internal_network_nat_rules(ex_gw_ip, cidr))
return rules
def internal_network_added(self, ri, ex_gw_port, network_id, port_id,
internal_cidr, mac_address):
interface_name = self.get_internal_device_name(port_id)
if not ip_lib.device_exists(interface_name,
root_helper=self.conf.root_helper,
namespace=ri.ns_name()):
self.driver.plug(network_id, port_id, interface_name, mac_address,
namespace=ri.ns_name(),
prefix=INTERNAL_DEV_PREFIX)
self.driver.init_l3(interface_name, [internal_cidr],
namespace=ri.ns_name())
ip_address = internal_cidr.split('/')[0]
self._send_gratuitous_arp_packet(ri, interface_name, ip_address)
if ex_gw_port:
ex_gw_ip = ex_gw_port['fixed_ips'][0]['ip_address']
for c, r in self.internal_network_nat_rules(ex_gw_ip,
internal_cidr):
ri.iptables_manager.ipv4['nat'].add_rule(c, r)
ri.iptables_manager.apply()
def internal_network_removed(self, ri, ex_gw_port, port_id, internal_cidr):
interface_name = self.get_internal_device_name(port_id)
if ip_lib.device_exists(interface_name,
root_helper=self.conf.root_helper,
namespace=ri.ns_name()):
self.driver.unplug(interface_name, namespace=ri.ns_name(),
prefix=INTERNAL_DEV_PREFIX)
if ex_gw_port:
ex_gw_ip = ex_gw_port['fixed_ips'][0]['ip_address']
for c, r in self.internal_network_nat_rules(ex_gw_ip,
internal_cidr):
ri.iptables_manager.ipv4['nat'].remove_rule(c, r)
ri.iptables_manager.apply()
def internal_network_nat_rules(self, ex_gw_ip, internal_cidr):
rules = [('snat', '-s %s -j SNAT --to-source %s' %
(internal_cidr, ex_gw_ip))]
if self.conf.metadata_ip:
rules.append(('POSTROUTING', '-s %s -d %s/32 -j ACCEPT' %
(internal_cidr, self.conf.metadata_ip)))
return rules
def floating_ip_added(self, ri, ex_gw_port, floating_ip, fixed_ip):
ip_cidr = str(floating_ip) + '/32'
interface_name = self.get_external_device_name(ex_gw_port['id'])
device = ip_lib.IPDevice(interface_name, self.conf.root_helper,
namespace=ri.ns_name())
if not ip_cidr in [addr['cidr'] for addr in device.addr.list()]:
net = netaddr.IPNetwork(ip_cidr)
device.addr.add(net.version, ip_cidr, str(net.broadcast))
self._send_gratuitous_arp_packet(ri, interface_name, floating_ip)
for chain, rule in self.floating_forward_rules(floating_ip, fixed_ip):
ri.iptables_manager.ipv4['nat'].add_rule(chain, rule)
ri.iptables_manager.apply()
def floating_ip_removed(self, ri, ex_gw_port, floating_ip, fixed_ip):
ip_cidr = str(floating_ip) + '/32'
net = netaddr.IPNetwork(ip_cidr)
interface_name = self.get_external_device_name(ex_gw_port['id'])
device = ip_lib.IPDevice(interface_name, self.conf.root_helper,
namespace=ri.ns_name())
device.addr.delete(net.version, ip_cidr)
for chain, rule in self.floating_forward_rules(floating_ip, fixed_ip):
ri.iptables_manager.ipv4['nat'].remove_rule(chain, rule)
ri.iptables_manager.apply()
def floating_forward_rules(self, floating_ip, fixed_ip):
return [('PREROUTING', '-d %s -j DNAT --to %s' %
(floating_ip, fixed_ip)),
('OUTPUT', '-d %s -j DNAT --to %s' %
(floating_ip, fixed_ip)),
('float-snat', '-s %s -j SNAT --to %s' %
(fixed_ip, floating_ip))]
def main():
conf = config.setup_conf()
conf.register_opts(L3NATAgent.OPTS)
conf.register_opts(interface.OPTS)
conf(sys.argv)
config.setup_logging(conf)
mgr = L3NATAgent(conf)
mgr.daemon_loop()
if __name__ == '__main__':
main()