¡@
OpenStack Study: firewall.py**** CubicPower OpenStack Study ****
# Copyright 2010 United States Government as represented by the # Administrator of the National Aeronautics and Space Administration. # All Rights Reserved. # Copyright (c) 2010 Citrix Systems, Inc. # # 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 nova import context from nova.openstack.common.gettextutils import _ from nova.openstack.common import jsonutils from nova.openstack.common import log as logging from nova.virt import firewall from nova.virt import netutils LOG = logging.getLogger(__name__)
**** CubicPower OpenStack Study **** class Dom0IptablesFirewallDriver(firewall.IptablesFirewallDriver): """Dom0IptablesFirewallDriver class This class provides an implementation for nova.virt.Firewall using iptables. This class is meant to be used with the xenapi backend and uses xenapi plugin to enforce iptables rules in dom0. """
**** CubicPower OpenStack Study **** def _plugin_execute(self, *cmd, **kwargs): # Prepare arguments for plugin call args = {} args.update(map(lambda x: (x, str(kwargs[x])), kwargs)) args['cmd_args'] = jsonutils.dumps(cmd) ret = self._session.call_plugin('xenhost', 'iptables_config', args) json_ret = jsonutils.loads(ret) return (json_ret['out'], json_ret['err'])
**** CubicPower OpenStack Study **** def __init__(self, virtapi, xenapi_session=None, **kwargs): from nova.network import linux_net super(Dom0IptablesFirewallDriver, self).__init__(virtapi, **kwargs) self._session = xenapi_session # Create IpTablesManager with executor through plugin self.iptables = linux_net.IptablesManager(self._plugin_execute) self.iptables.ipv4['filter'].add_chain('sg-fallback') self.iptables.ipv4['filter'].add_rule('sg-fallback', '-j DROP') self.iptables.ipv6['filter'].add_chain('sg-fallback') self.iptables.ipv6['filter'].add_rule('sg-fallback', '-j DROP')
**** CubicPower OpenStack Study **** def _build_tcp_udp_rule(self, rule, version): if rule['from_port'] == rule['to_port']: return ['--dport', '%s' % (rule['from_port'],)] else: # No multiport needed for XS! return ['--dport', '%s:%s' % (rule['from_port'], rule['to_port'])]
**** CubicPower OpenStack Study **** def _provider_rules(self): """Generate a list of rules from provider for IP4 & IP6. Note: We could not use the common code from virt.firewall because XS doesn't accept the '-m multiport' option. """ ctxt = context.get_admin_context() ipv4_rules = [] ipv6_rules = [] rules = self._virtapi.provider_fw_rule_get_all(ctxt) for rule in rules: LOG.debug(_('Adding provider rule: %s'), rule['cidr']) version = netutils.get_ip_version(rule['cidr']) if version == 4: fw_rules = ipv4_rules else: fw_rules = ipv6_rules protocol = rule['protocol'] if version == 6 and protocol == 'icmp': protocol = 'icmpv6' args = ['-p', protocol, '-s', rule['cidr']] if protocol in ['udp', 'tcp']: if rule['from_port'] == rule['to_port']: args += ['--dport', '%s' % (rule['from_port'],)] else: args += ['--dport', '%s:%s' % (rule['from_port'], rule['to_port'])] elif protocol == 'icmp': icmp_type = rule['from_port'] icmp_code = rule['to_port'] if icmp_type == -1: icmp_type_arg = None else: icmp_type_arg = '%s' % icmp_type if not icmp_code == -1: icmp_type_arg += '/%s' % icmp_code if icmp_type_arg: if version == 4: args += ['-m', 'icmp', '--icmp-type', icmp_type_arg] elif version == 6: args += ['-m', 'icmp6', '--icmpv6-type', icmp_type_arg] args += ['-j DROP'] fw_rules += [' '.join(args)] return ipv4_rules, ipv6_rules
|