ironic-inspector/ironic_inspector/firewall.py
Dmitry Tantsur d6404d2f99 Rename discoverd -> inspector
As agreed on the summit I'm renaming the python modules
and doing some adjustments:
* This is a breaking change, so version is bumped to 2.0.0
* Used this chance to split conf options over proper sections
* RELEASES.rst is gone; it's too hard to keep it up-to-date;
  anyway git does better job at doing history
* Dropped deprecated option ports_for_inactive_interfaces
* Dropped old /v1/discover endpoint and associated client call
* No longer set on_discovery and newly_discovered in Node.extra
  (deprecated since 1.0.0, superseded by the get status API)
* Default firewall chain name is "ironic-inspector" and
  is configurable

Notes:
* Some links will be updated after real move.
* Stable branches will probably use the old name.
* Some usage of discovery word is left in context of
  "discovered data"
* DIB element will probably be deprecated, so leaving it
  alone for now.
* Some usages of word "discovery" in the README will be updated
  later to make this patch a bit smaller
* Ramdisk code will be moved to IPA, so not touching it too much

Change-Id: I59f1f5bfb1248ab69973dab845aa028df493054e
2015-05-29 09:06:56 +02:00

133 lines
4.2 KiB
Python

# 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 logging
import subprocess
from eventlet import semaphore
from oslo_config import cfg
from ironic_inspector.common.i18n import _LE
from ironic_inspector import node_cache
from ironic_inspector import utils
CONF = cfg.CONF
LOG = logging.getLogger("ironic_inspector.firewall")
NEW_CHAIN = None
CHAIN = None
INTERFACE = None
LOCK = semaphore.BoundedSemaphore()
def _iptables(*args, **kwargs):
cmd = ('iptables',) + args
ignore = kwargs.pop('ignore', False)
LOG.debug('Running iptables %s', args)
kwargs['stderr'] = subprocess.STDOUT
try:
subprocess.check_output(cmd, **kwargs)
except subprocess.CalledProcessError as exc:
if ignore:
LOG.debug('ignoring failed iptables %s:\n%s', args, exc.output)
else:
LOG.error(_LE('iptables %(iptables)s failed:\n%(exc)s') %
{'iptables': args, 'exc': exc.output})
raise
def init():
"""Initialize firewall management.
Must be called one on start-up.
"""
if not CONF.firewall.manage_firewall:
return
global INTERFACE, CHAIN, NEW_CHAIN
INTERFACE = CONF.firewall.dnsmasq_interface
CHAIN = CONF.firewall.firewall_chain
NEW_CHAIN = CHAIN + '_temp'
_clean_up(CHAIN)
# Not really needed, but helps to validate that we have access to iptables
_iptables('-N', CHAIN)
def _clean_up(chain):
_iptables('-D', 'INPUT', '-i', INTERFACE, '-p', 'udp',
'--dport', '67', '-j', chain,
ignore=True)
_iptables('-F', chain, ignore=True)
_iptables('-X', chain, ignore=True)
def clean_up():
"""Clean up everything before exiting."""
if not CONF.firewall.manage_firewall:
return
_clean_up(CHAIN)
_clean_up(NEW_CHAIN)
def update_filters(ironic=None):
"""Update firewall filter rules for introspection.
Gives access to PXE boot port for any machine, except for those,
whose MAC is registered in Ironic and is not on introspection right now.
This function is called from both introspection initialization code and
from periodic task. This function is supposed to be resistant to unexpected
iptables state.
``init()`` function must be called once before any call to this function.
This function is using ``eventlet`` semaphore to serialize access from
different green threads.
Does nothing, if firewall management is disabled in configuration.
:param ironic: Ironic client instance, optional.
"""
if not CONF.firewall.manage_firewall:
return
assert INTERFACE is not None
ironic = utils.get_client() if ironic is None else ironic
with LOCK:
macs_active = set(p.address for p in ironic.port.list(limit=0))
to_blacklist = macs_active - node_cache.active_macs()
LOG.debug('Blacklisting active MAC\'s %s', to_blacklist)
# Clean up a bit to account for possible troubles on previous run
_clean_up(NEW_CHAIN)
# Operate on temporary chain
_iptables('-N', NEW_CHAIN)
# - Blacklist active macs, so that nova can boot them
for mac in to_blacklist:
_iptables('-A', NEW_CHAIN, '-m', 'mac',
'--mac-source', mac, '-j', 'DROP')
# - Whitelist everything else
_iptables('-A', NEW_CHAIN, '-j', 'ACCEPT')
# Swap chains
_iptables('-I', 'INPUT', '-i', INTERFACE, '-p', 'udp',
'--dport', '67', '-j', NEW_CHAIN)
_iptables('-D', 'INPUT', '-i', INTERFACE, '-p', 'udp',
'--dport', '67', '-j', CHAIN,
ignore=True)
_iptables('-F', CHAIN, ignore=True)
_iptables('-X', CHAIN, ignore=True)
_iptables('-E', NEW_CHAIN, CHAIN)