422 lines
14 KiB
Python
422 lines
14 KiB
Python
# vim: tabstop=4 shiftwidth=4 softtabstop=4
|
|
|
|
# Copyright 2012 OpenStack LLC
|
|
# 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.
|
|
|
|
import abc
|
|
import os
|
|
import re
|
|
import socket
|
|
import StringIO
|
|
import sys
|
|
import tempfile
|
|
|
|
import netaddr
|
|
from oslo.config import cfg
|
|
|
|
from quantum.agent.linux import ip_lib
|
|
from quantum.agent.linux import utils
|
|
from quantum.openstack.common import jsonutils
|
|
from quantum.openstack.common import log as logging
|
|
|
|
LOG = logging.getLogger(__name__)
|
|
|
|
OPTS = [
|
|
cfg.StrOpt('dhcp_confs',
|
|
default='$state_path/dhcp',
|
|
help=_('Location to store DHCP server config files')),
|
|
cfg.IntOpt('dhcp_lease_time',
|
|
default=120,
|
|
help=_('Lifetime of a DHCP lease in seconds')),
|
|
cfg.StrOpt('dhcp_domain',
|
|
default='openstacklocal',
|
|
help=_('Domain to use for building the hostnames')),
|
|
cfg.StrOpt('dnsmasq_config_file',
|
|
default='',
|
|
help=_('Override the default dnsmasq settings with this file')),
|
|
cfg.StrOpt('dnsmasq_dns_server',
|
|
help=_('Use another DNS server before any in '
|
|
'/etc/resolv.conf.')),
|
|
]
|
|
|
|
IPV4 = 4
|
|
IPV6 = 6
|
|
UDP = 'udp'
|
|
TCP = 'tcp'
|
|
DNS_PORT = 53
|
|
DHCPV4_PORT = 67
|
|
DHCPV6_PORT = 467
|
|
METADATA_DEFAULT_IP = '169.254.169.254'
|
|
|
|
|
|
class DhcpBase(object):
|
|
__metaclass__ = abc.ABCMeta
|
|
|
|
def __init__(self, conf, network, root_helper='sudo',
|
|
device_delegate=None, namespace=None):
|
|
self.conf = conf
|
|
self.network = network
|
|
self.root_helper = root_helper
|
|
self.device_delegate = device_delegate
|
|
self.namespace = namespace
|
|
|
|
@abc.abstractmethod
|
|
def enable(self):
|
|
"""Enables DHCP for this network."""
|
|
|
|
@abc.abstractmethod
|
|
def disable(self, retain_port=False):
|
|
"""Disable dhcp for this network."""
|
|
|
|
def restart(self):
|
|
"""Restart the dhcp service for the network."""
|
|
self.disable(retain_port=True)
|
|
self.enable()
|
|
|
|
@abc.abstractproperty
|
|
def active(self):
|
|
"""Boolean representing the running state of the DHCP server."""
|
|
|
|
@abc.abstractmethod
|
|
def reload_allocations(self):
|
|
"""Force the DHCP server to reload the assignment database."""
|
|
|
|
|
|
class DhcpLocalProcess(DhcpBase):
|
|
PORTS = []
|
|
|
|
def _enable_dhcp(self):
|
|
"""check if there is a subnet within the network with dhcp enabled."""
|
|
for subnet in self.network.subnets:
|
|
if subnet.enable_dhcp:
|
|
return True
|
|
return False
|
|
|
|
def enable(self):
|
|
"""Enables DHCP for this network by spawning a local process."""
|
|
interface_name = self.device_delegate.setup(self.network,
|
|
reuse_existing=True)
|
|
if self.active:
|
|
self.restart()
|
|
elif self._enable_dhcp():
|
|
self.interface_name = interface_name
|
|
self.spawn_process()
|
|
|
|
def disable(self, retain_port=False):
|
|
"""Disable DHCP for this network by killing the local process."""
|
|
pid = self.pid
|
|
|
|
if self.active:
|
|
cmd = ['kill', '-9', pid]
|
|
if self.namespace:
|
|
ip_wrapper = ip_lib.IPWrapper(self.root_helper, self.namespace)
|
|
ip_wrapper.netns.execute(cmd)
|
|
else:
|
|
utils.execute(cmd, self.root_helper)
|
|
|
|
if not retain_port:
|
|
self.device_delegate.destroy(self.network, self.interface_name)
|
|
|
|
elif pid:
|
|
LOG.debug(_('DHCP for %(net_id)s pid %(pid)d is stale, ignoring '
|
|
'command'), {'net_id': self.network.id, 'pid': pid})
|
|
else:
|
|
LOG.debug(_('No DHCP started for %s'), self.network.id)
|
|
|
|
def get_conf_file_name(self, kind, ensure_conf_dir=False):
|
|
"""Returns the file name for a given kind of config file."""
|
|
confs_dir = os.path.abspath(os.path.normpath(self.conf.dhcp_confs))
|
|
conf_dir = os.path.join(confs_dir, self.network.id)
|
|
if ensure_conf_dir:
|
|
if not os.path.isdir(conf_dir):
|
|
os.makedirs(conf_dir, 0755)
|
|
|
|
return os.path.join(conf_dir, kind)
|
|
|
|
def _get_value_from_conf_file(self, kind, converter=None):
|
|
"""A helper function to read a value from one of the state files."""
|
|
file_name = self.get_conf_file_name(kind)
|
|
msg = _('Error while reading %s')
|
|
|
|
try:
|
|
with open(file_name, 'r') as f:
|
|
try:
|
|
return converter and converter(f.read()) or f.read()
|
|
except ValueError, e:
|
|
msg = _('Unable to convert value in %s')
|
|
except IOError, e:
|
|
msg = _('Unable to access %s')
|
|
|
|
LOG.debug(msg % file_name)
|
|
return None
|
|
|
|
@property
|
|
def pid(self):
|
|
"""Last known pid for the DHCP process spawned for this network."""
|
|
return self._get_value_from_conf_file('pid', int)
|
|
|
|
@property
|
|
def active(self):
|
|
pid = self.pid
|
|
if pid is None:
|
|
return False
|
|
|
|
cmd = ['cat', '/proc/%s/cmdline' % pid]
|
|
try:
|
|
return self.network.id in utils.execute(cmd, self.root_helper)
|
|
except RuntimeError, e:
|
|
return False
|
|
|
|
@property
|
|
def interface_name(self):
|
|
return self._get_value_from_conf_file('interface')
|
|
|
|
@interface_name.setter
|
|
def interface_name(self, value):
|
|
interface_file_path = self.get_conf_file_name('interface',
|
|
ensure_conf_dir=True)
|
|
replace_file(interface_file_path, value)
|
|
|
|
@abc.abstractmethod
|
|
def spawn_process(self):
|
|
pass
|
|
|
|
|
|
class Dnsmasq(DhcpLocalProcess):
|
|
# The ports that need to be opened when security policies are active
|
|
# on the Quantum port used for DHCP. These are provided as a convenience
|
|
# for users of this class.
|
|
PORTS = {IPV4: [(UDP, DNS_PORT), (TCP, DNS_PORT), (UDP, DHCPV4_PORT)],
|
|
IPV6: [(UDP, DNS_PORT), (TCP, DNS_PORT), (UDP, DHCPV6_PORT)],
|
|
}
|
|
|
|
_TAG_PREFIX = 'tag%d'
|
|
|
|
QUANTUM_NETWORK_ID_KEY = 'QUANTUM_NETWORK_ID'
|
|
QUANTUM_RELAY_SOCKET_PATH_KEY = 'QUANTUM_RELAY_SOCKET_PATH'
|
|
|
|
def spawn_process(self):
|
|
"""Spawns a Dnsmasq process for the network."""
|
|
env = {
|
|
self.QUANTUM_NETWORK_ID_KEY: self.network.id,
|
|
self.QUANTUM_RELAY_SOCKET_PATH_KEY:
|
|
self.conf.dhcp_lease_relay_socket
|
|
}
|
|
|
|
cmd = [
|
|
'dnsmasq',
|
|
'--no-hosts',
|
|
'--no-resolv',
|
|
'--strict-order',
|
|
'--bind-interfaces',
|
|
'--interface=%s' % self.interface_name,
|
|
'--except-interface=lo',
|
|
'--pid-file=%s' % self.get_conf_file_name(
|
|
'pid', ensure_conf_dir=True),
|
|
#TODO (mark): calculate value from cidr (defaults to 150)
|
|
#'--dhcp-lease-max=%s' % ?,
|
|
'--dhcp-hostsfile=%s' % self._output_hosts_file(),
|
|
'--dhcp-optsfile=%s' % self._output_opts_file(),
|
|
'--dhcp-script=%s' % self._lease_relay_script_path(),
|
|
'--leasefile-ro',
|
|
]
|
|
|
|
for i, subnet in enumerate(self.network.subnets):
|
|
# if a subnet is specified to have dhcp disabled
|
|
if not subnet.enable_dhcp:
|
|
continue
|
|
if subnet.ip_version == 4:
|
|
mode = 'static'
|
|
else:
|
|
# TODO (mark): how do we indicate other options
|
|
# ra-only, slaac, ra-nameservers, and ra-stateless.
|
|
mode = 'static'
|
|
cmd.append('--dhcp-range=set:%s,%s,%s,%ss' %
|
|
(self._TAG_PREFIX % i,
|
|
netaddr.IPNetwork(subnet.cidr).network,
|
|
mode,
|
|
self.conf.dhcp_lease_time))
|
|
|
|
cmd.append('--conf-file=%s' % self.conf.dnsmasq_config_file)
|
|
if self.conf.dnsmasq_dns_server:
|
|
cmd.append('--server=%s' % self.conf.dnsmasq_dns_server)
|
|
|
|
if self.conf.dhcp_domain:
|
|
cmd.append('--domain=%s' % self.conf.dhcp_domain)
|
|
|
|
if self.namespace:
|
|
ip_wrapper = ip_lib.IPWrapper(self.root_helper, self.namespace)
|
|
ip_wrapper.netns.execute(cmd, addl_env=env)
|
|
else:
|
|
# For normal sudo prepend the env vars before command
|
|
cmd = ['%s=%s' % pair for pair in env.items()] + cmd
|
|
utils.execute(cmd, self.root_helper)
|
|
|
|
def reload_allocations(self):
|
|
"""Rebuild the dnsmasq config and signal the dnsmasq to reload."""
|
|
|
|
# If all subnets turn off dhcp, kill the process.
|
|
if not self._enable_dhcp():
|
|
self.disable()
|
|
LOG.debug(_('Killing dhcpmasq for network since all subnets have '
|
|
'turned off DHCP: %s'), self.network.id)
|
|
return
|
|
|
|
self._output_hosts_file()
|
|
self._output_opts_file()
|
|
cmd = ['kill', '-HUP', self.pid]
|
|
|
|
if self.namespace:
|
|
ip_wrapper = ip_lib.IPWrapper(self.root_helper, self.namespace)
|
|
ip_wrapper.netns.execute(cmd)
|
|
else:
|
|
utils.execute(cmd, self.root_helper)
|
|
LOG.debug(_('Reloading allocations for network: %s'), self.network.id)
|
|
|
|
def _output_hosts_file(self):
|
|
"""Writes a dnsmasq compatible hosts file."""
|
|
r = re.compile('[:.]')
|
|
buf = StringIO.StringIO()
|
|
|
|
for port in self.network.ports:
|
|
for alloc in port.fixed_ips:
|
|
name = '%s.%s' % (r.sub('-', alloc.ip_address),
|
|
self.conf.dhcp_domain)
|
|
buf.write('%s,%s,%s\n' %
|
|
(port.mac_address, name, alloc.ip_address))
|
|
|
|
name = self.get_conf_file_name('host')
|
|
replace_file(name, buf.getvalue())
|
|
return name
|
|
|
|
def _output_opts_file(self):
|
|
"""Write a dnsmasq compatible options file."""
|
|
|
|
if self.conf.enable_isolated_metadata:
|
|
subnet_to_interface_ip = self._make_subnet_interface_ip_map()
|
|
|
|
options = []
|
|
for i, subnet in enumerate(self.network.subnets):
|
|
if not subnet.enable_dhcp:
|
|
continue
|
|
if subnet.dns_nameservers:
|
|
options.append(
|
|
self._format_option(i, 'dns-server',
|
|
','.join(subnet.dns_nameservers)))
|
|
|
|
host_routes = ["%s,%s" % (hr.destination, hr.nexthop)
|
|
for hr in subnet.host_routes]
|
|
|
|
# Add host routes for isolated network segments
|
|
enable_metadata = (
|
|
self.conf.enable_isolated_metadata
|
|
and not subnet.gateway_ip
|
|
and subnet.ip_version == 4)
|
|
|
|
if enable_metadata:
|
|
subnet_dhcp_ip = subnet_to_interface_ip[subnet.id]
|
|
host_routes.append(
|
|
'%s/32,%s' % (METADATA_DEFAULT_IP, subnet_dhcp_ip)
|
|
)
|
|
|
|
if host_routes:
|
|
options.append(
|
|
self._format_option(i, 'classless-static-route',
|
|
','.join(host_routes)))
|
|
|
|
if subnet.ip_version == 4:
|
|
if subnet.gateway_ip:
|
|
options.append(self._format_option(i, 'router',
|
|
subnet.gateway_ip))
|
|
else:
|
|
options.append(self._format_option(i, 'router'))
|
|
|
|
name = self.get_conf_file_name('opts')
|
|
replace_file(name, '\n'.join(options))
|
|
return name
|
|
|
|
def _make_subnet_interface_ip_map(self):
|
|
ip_dev = ip_lib.IPDevice(
|
|
self.interface_name,
|
|
self.root_helper,
|
|
self.namespace
|
|
)
|
|
|
|
subnet_lookup = dict(
|
|
(netaddr.IPNetwork(subnet.cidr), subnet.id)
|
|
for subnet in self.network.subnets
|
|
)
|
|
|
|
retval = {}
|
|
|
|
for addr in ip_dev.addr.list():
|
|
ip_net = netaddr.IPNetwork(addr['cidr'])
|
|
|
|
if ip_net in subnet_lookup:
|
|
retval[subnet_lookup[ip_net]] = addr['cidr'].split('/')[0]
|
|
|
|
return retval
|
|
|
|
def _lease_relay_script_path(self):
|
|
return os.path.join(os.path.dirname(sys.argv[0]),
|
|
'quantum-dhcp-agent-dnsmasq-lease-update')
|
|
|
|
def _format_option(self, index, option_name, *args):
|
|
return ','.join(('tag:' + self._TAG_PREFIX % index,
|
|
'option:%s' % option_name) + args)
|
|
|
|
@classmethod
|
|
def lease_update(cls):
|
|
network_id = os.environ.get(cls.QUANTUM_NETWORK_ID_KEY)
|
|
dhcp_relay_socket = os.environ.get(cls.QUANTUM_RELAY_SOCKET_PATH_KEY)
|
|
|
|
action = sys.argv[1]
|
|
if action not in ('add', 'del', 'old'):
|
|
sys.exit()
|
|
|
|
mac_address = sys.argv[2]
|
|
ip_address = sys.argv[3]
|
|
|
|
if action == 'del':
|
|
lease_remaining = 0
|
|
else:
|
|
lease_remaining = int(os.environ.get('DNSMASQ_TIME_REMAINING', 0))
|
|
|
|
data = dict(network_id=network_id, mac_address=mac_address,
|
|
ip_address=ip_address, lease_remaining=lease_remaining)
|
|
|
|
if os.path.exists(dhcp_relay_socket):
|
|
sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
|
|
sock.connect(dhcp_relay_socket)
|
|
sock.send(jsonutils.dumps(data))
|
|
sock.close()
|
|
|
|
|
|
def replace_file(file_name, data):
|
|
"""Replaces the contents of file_name with data in a safe manner.
|
|
|
|
First write to a temp file and then rename. Since POSIX renames are
|
|
atomic, the file is unlikely to be corrupted by competing writes.
|
|
|
|
We create the tempfile on the same device to ensure that it can be renamed.
|
|
"""
|
|
|
|
base_dir = os.path.dirname(os.path.abspath(file_name))
|
|
tmp_file = tempfile.NamedTemporaryFile('w+', dir=base_dir, delete=False)
|
|
tmp_file.write(data)
|
|
tmp_file.close()
|
|
os.chmod(tmp_file.name, 0644)
|
|
os.rename(tmp_file.name, file_name)
|