neutron/neutron/agent/metadata/driver_base.py

284 lines
12 KiB
Python

# Copyright 2014 OpenStack Foundation.
# 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 grp
import os
import pwd
import signal
from neutron_lib import exceptions
from oslo_config import cfg
from oslo_log import log as logging
from neutron._i18n import _
from neutron.agent.linux import external_process
from neutron.agent.linux import ip_lib
from neutron.agent.linux import utils as linux_utils
from neutron.common import metadata as comm_meta
from neutron.common import utils as common_utils
LOG = logging.getLogger(__name__)
SIGTERM_TIMEOUT = 5
METADATA_SERVICE_NAME = 'metadata-proxy'
HAPROXY_SERVICE = 'haproxy'
_UNLIMITED_CONFIG_TEMPLATE = """
listen listener
bind %(host)s:%(port)s
%(bind_v6_line)s
server metadata %(unix_socket_path)s
"""
class HaproxyConfiguratorBase(object):
PROXY_CONFIG_DIR = None
HEADER_CONFIG_TEMPLATE = None
def __init__(self, network_id, router_id, unix_socket_path, host, port,
user, group, state_path, pid_file, rate_limiting_config,
host_v6=None, bind_interface=None):
self.network_id = network_id
self.router_id = router_id
if network_id is None and router_id is None:
raise exceptions.NetworkIdOrRouterIdRequiredError()
self.host = host
self.host_v6 = host_v6
self.bind_interface = bind_interface
self.port = port
self.user = user
self.group = group
self.state_path = state_path
self.unix_socket_path = unix_socket_path
self.pidfile = pid_file
self.rate_limiting_config = rate_limiting_config
self.log_level = (
'debug' if logging.is_debug_enabled(cfg.CONF) else 'info')
# log-tag will cause entries to have the string pre-pended, so use
# the uuid haproxy will be started with. Additionally, if it
# starts with "haproxy" then things will get logged to
# /var/log/haproxy.log on Debian distros, instead of to syslog.
uuid = network_id or router_id
self.log_tag = "haproxy-{}-{}".format(METADATA_SERVICE_NAME, uuid)
def create_config_file(self):
"""Create the config file for haproxy."""
# Need to convert uid/gid into username/group
try:
username = pwd.getpwuid(int(self.user)).pw_name
except (ValueError, KeyError):
try:
username = pwd.getpwnam(self.user).pw_name
except KeyError:
raise comm_meta.InvalidUserOrGroupException(
_("Invalid user/uid: '%s'") % self.user)
try:
groupname = grp.getgrgid(int(self.group)).gr_name
except (ValueError, KeyError):
try:
groupname = grp.getgrnam(self.group).gr_name
except KeyError:
raise comm_meta.InvalidUserOrGroupException(
_("Invalid group/gid: '%s'") % self.group)
cfg_info = {
'host': self.host,
'port': self.port,
'unix_socket_path': self.unix_socket_path,
'user': username,
'group': groupname,
'pidfile': self.pidfile,
'log_level': self.log_level,
'log_tag': self.log_tag,
'bind_v6_line': '',
}
if self.host_v6 and self.bind_interface:
cfg_info['bind_v6_line'] = (
'bind %s:%s interface %s' % (
self.host_v6, self.port, self.bind_interface)
)
# If using the network ID, delete any spurious router ID that might
# have been in the request, same for network ID when using router ID.
# This is to prevent someone from spoofing a metadata request using
# the proxy via an external network. See LP #1865036 for more info.
# This only applies to the non-OVN driver.
if self.network_id:
cfg_info['res_type'] = 'Network'
cfg_info['res_id'] = self.network_id
cfg_info['res_type_del'] = 'Router'
else:
cfg_info['res_type'] = 'Router'
cfg_info['res_id'] = self.router_id
cfg_info['res_type_del'] = 'Network'
haproxy_cfg = comm_meta.get_haproxy_config(cfg_info,
self.rate_limiting_config,
self.HEADER_CONFIG_TEMPLATE,
_UNLIMITED_CONFIG_TEMPLATE)
LOG.debug("haproxy_cfg = %s", haproxy_cfg)
cfg_dir = self.get_config_path(self.state_path)
# uuid has to be included somewhere in the command line so that it can
# be tracked by process_monitor.
self.cfg_path = os.path.join(cfg_dir, "%s.conf" % cfg_info['res_id'])
if not os.path.exists(cfg_dir):
os.makedirs(cfg_dir)
with open(self.cfg_path, "w") as cfg_file:
cfg_file.write(haproxy_cfg)
@classmethod
def get_config_path(cls, state_path):
return os.path.join(state_path or cfg.CONF.state_path,
cls.PROXY_CONFIG_DIR)
@classmethod
def cleanup_config_file(cls, uuid, state_path):
"""Delete config file created when metadata proxy was spawned."""
# Delete config file if it exists
cfg_path = os.path.join(
cls.get_config_path(state_path),
"%s.conf" % uuid)
linux_utils.delete_if_exists(cfg_path, run_as_root=True)
class MetadataDriverBase(object, metaclass=abc.ABCMeta):
@staticmethod
@abc.abstractmethod
def haproxy_configurator():
"""Returns the HaproxyConfigurator for the class."""
pass
@classmethod
def _get_metadata_proxy_user_group(cls, conf):
user = conf.metadata_proxy_user or str(os.geteuid())
group = conf.metadata_proxy_group or str(os.getegid())
return user, group
@classmethod
def _get_metadata_proxy_callback(cls, bind_address, port, conf,
network_id=None, router_id=None,
bind_address_v6=None,
bind_interface=None):
def callback(pid_file):
metadata_proxy_socket = conf.metadata_proxy_socket
user, group = cls._get_metadata_proxy_user_group(conf)
configurator = cls.haproxy_configurator()
haproxy = configurator(network_id,
router_id,
metadata_proxy_socket,
bind_address,
port,
user,
group,
conf.state_path,
pid_file,
conf.metadata_rate_limiting,
bind_address_v6,
bind_interface)
haproxy.create_config_file()
proxy_cmd = [HAPROXY_SERVICE, '-f', haproxy.cfg_path]
return proxy_cmd
return callback
@classmethod
def spawn_monitored_metadata_proxy(cls, monitor, ns_name, port, conf,
bind_address="0.0.0.0", network_id=None,
router_id=None, bind_address_v6=None,
bind_interface=None):
if bind_interface is not None and bind_address_v6 is not None:
# HAProxy cannot bind() until IPv6 Duplicate Address Detection
# completes. We must wait until the address leaves its 'tentative'
# state.
try:
ip_lib.IpAddrCommand(
parent=ip_lib.IPDevice(name=bind_interface,
namespace=ns_name)
).wait_until_address_ready(address=bind_address_v6)
except ip_lib.DADFailed as exc:
# This failure means that another DHCP agent has already
# configured this metadata address, so all requests will
# be via that single agent.
LOG.info('DAD failed for address %(address)s on interface '
'%(interface)s in namespace %(namespace)s on network '
'%(network)s, deleting it. Exception: %(exception)s',
{'address': bind_address_v6,
'interface': bind_interface,
'namespace': ns_name,
'network': network_id,
'exception': str(exc)})
try:
ip_lib.delete_ip_address(bind_address_v6, bind_interface,
namespace=ns_name)
except Exception as exc:
# do not re-raise a delete failure, just log
LOG.info('Address deletion failure: %s', str(exc))
# Do not use the address or interface when DAD fails
bind_address_v6 = bind_interface = None
uuid = network_id or router_id
callback = cls._get_metadata_proxy_callback(
bind_address, port, conf,
network_id=network_id, router_id=router_id,
bind_address_v6=bind_address_v6, bind_interface=bind_interface)
pm = cls._get_metadata_proxy_process_manager(uuid, conf,
ns_name=ns_name,
callback=callback)
try:
pm.enable(ensure_active=True)
except exceptions.ProcessExecutionError as exec_err:
LOG.error("Encountered process execution error %(err)s while "
"starting process in namespace %(ns)s",
{"err": exec_err, "ns": ns_name})
return
monitor.register(uuid, METADATA_SERVICE_NAME, pm)
@classmethod
def destroy_monitored_metadata_proxy(cls, monitor, uuid, conf, ns_name):
monitor.unregister(uuid, METADATA_SERVICE_NAME)
pm = cls._get_metadata_proxy_process_manager(uuid, conf,
ns_name=ns_name)
pm.disable(sig=str(int(signal.SIGTERM)))
try:
common_utils.wait_until_true(lambda: not pm.active,
timeout=SIGTERM_TIMEOUT)
except common_utils.WaitTimeout:
LOG.warning('Metadata process %s did not finish after SIGTERM '
'signal in %s seconds, sending SIGKILL signal',
pm.pid, SIGTERM_TIMEOUT)
pm.disable(sig=str(int(signal.SIGKILL)))
# Delete metadata proxy config.
configurator = cls.haproxy_configurator()
configurator.cleanup_config_file(uuid, cfg.CONF.state_path)
@classmethod
def _get_metadata_proxy_process_manager(cls, router_id, conf, ns_name=None,
callback=None):
return external_process.ProcessManager(
conf=conf,
uuid=router_id,
namespace=ns_name,
service=HAPROXY_SERVICE,
default_cmd_callback=callback)