Provide Fedora support for StrongSwan

The initial release of StrongSwan VPNaaS driver only support Ubuntu.
This patch will provide the Fedora support. The different usage of
StrongSwan between Fedora and Ubuntu are:
- Uses 'strongswan' CLI command instead of 'ipsec'
- Configuration files location is different
- Strongswan.d directory in template directory does not include
  'charon' directory

Change-Id: I27d8518d1d8110453d4674a0c6fb3cb6072a32f0
Closes-bug: 1444776
Closes-bug: 1441788

etc/neutron/rootwrap.d/vpnaas.filters

@@ -11,5 +11,6 @@
 ip: IpFilter, ip, root
 ip_exec: IpNetnsExecFilter, ip, root
 ipsec: CommandFilter, ipsec, root
+strongswan: CommandFilter, strongswan, root
 neutron_netns_wrapper: CommandFilter, neutron-vpn-netns-wrapper, root
 neutron_netns_wrapper_local: CommandFilter, /usr/local/bin/neutron-vpn-netns-wrapper, root

etc/vpn_agent.ini

@@ -12,6 +12,7 @@
 # vpn_device_driver=neutron_vpnaas.services.vpn.device_drivers.cisco_ipsec.CiscoCsrIPsecDriver
 # vpn_device_driver=neutron_vpnaas.services.vpn.device_drivers.vyatta_ipsec.VyattaIPSecDriver
 # vpn_device_driver=neutron_vpnaas.services.vpn.device_drivers.strongswan_ipsec.StrongSwanDriver
+# vpn_device_driver=neutron_vpnaas.services.vpn.device_drivers.fedora_strongswan_ipsec.FedoraStrongSwanDriver
 # vpn_device_driver=another_driver
 
 [ipsec]

neutron_vpnaas/services/vpn/device_drivers/fedora_strongswan_ipsec.py

@@ -0,0 +1,107 @@
+# Copyright (c) 2015 IBM, 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.
+
+import os
+
+from oslo_config import cfg
+from oslo_log import log as logging
+
+from neutron_vpnaas.services.vpn.device_drivers import ipsec
+from neutron_vpnaas.services.vpn.device_drivers import strongswan_ipsec
+
+LOG = logging.getLogger(__name__)
+TEMPLATE_PATH = os.path.dirname(os.path.abspath(__file__))
+
+cfg.CONF.set_default(name='default_config_area',
+                     default=os.path.join(
+                         TEMPLATE_PATH,
+                         '/usr/share/strongswan/templates/'
+                         'config/strongswan.d'),
+                     group='strongswan')
+
+
+class FedoraStrongSwanProcess(strongswan_ipsec.StrongSwanProcess):
+
+    binary = 'strongswan'
+    CONFIG_DIRS = [
+        'var/run',
+        'log',
+        'etc',
+        'etc/strongswan/ipsec.d/aacerts',
+        'etc/strongswan/ipsec.d/acerts',
+        'etc/strongswan/ipsec.d/cacerts',
+        'etc/strongswan/ipsec.d/certs',
+        'etc/strongswan/ipsec.d/crls',
+        'etc/strongswan/ipsec.d/ocspcerts',
+        'etc/strongswan/ipsec.d/policies',
+        'etc/strongswan/ipsec.d/private',
+        'etc/strongswan/ipsec.d/reqs',
+        'etc/pki/nssdb/'
+    ]
+    STATUS_NOT_RUNNING_RE = ('Command:.*[ipsec|strongswan].*status.*'
+                             'Exit code: [1|3] ')
+
+    def __init__(self, conf, process_id, vpnservice, namespace):
+        super(FedoraStrongSwanProcess, self).__init__(conf, process_id,
+                                                      vpnservice, namespace)
+
+    def ensure_configs(self):
+        """Generate config files which are needed for StrongSwan.
+
+        If there is no directory, this function will create
+        dirs.
+        """
+        self.ensure_config_dir(self.vpnservice)
+        self.ensure_config_file(
+            'ipsec.conf',
+            cfg.CONF.strongswan.ipsec_config_template,
+            self.vpnservice)
+        self.ensure_config_file(
+            'strongswan.conf',
+            cfg.CONF.strongswan.strongswan_config_template,
+            self.vpnservice)
+        self.ensure_config_file(
+            'ipsec.secrets',
+            cfg.CONF.strongswan.ipsec_secret_template,
+            self.vpnservice)
+        self.copy_and_overwrite(cfg.CONF.strongswan.default_config_area,
+                                self._get_config_filename('strongswan.d'))
+        # Fedora uses /usr/share/strongswan/templates/config/ as strongswan
+        # template directory. But /usr/share/strongswan/templates/config/
+        # strongswan.d does not include charon. Those configuration files
+        # are in /usr/share/strongswan/templates/config/plugins directory.
+        charon_dir = os.path.join(
+            cfg.CONF.strongswan.default_config_area,
+            'charon')
+        if not os.path.exists(charon_dir):
+            plugins_dir = os.path.join(
+                cfg.CONF.strongswan.default_config_area, '../plugins')
+            self.copy_and_overwrite(
+                plugins_dir,
+                self._get_config_filename('strongswan.d/charon'))
+
+    def _get_config_filename(self, kind):
+        config_dir = '%s/strongswan' % self.etc_dir
+        return os.path.join(config_dir, kind)
+
+
+class FedoraStrongSwanDriver(ipsec.IPsecDriver):
+
+    def create_process(self, process_id, vpnservice, namespace):
+        return FedoraStrongSwanProcess(
+            self.conf,
+            process_id,
+            vpnservice,
+            namespace)

neutron_vpnaas/tests/unit/services/vpn/device_drivers/test_ipsec.py

@@ -25,6 +25,7 @@ from neutron.plugins.common import constants
 from oslo_config import cfg
 
 from neutron_vpnaas.extensions import vpnaas
+from neutron_vpnaas.services.vpn.device_drivers import fedora_strongswan_ipsec
 from neutron_vpnaas.services.vpn.device_drivers import ipsec as openswan_ipsec
 from neutron_vpnaas.services.vpn.device_drivers import strongswan_ipsec
 from neutron_vpnaas.tests import base
@@ -727,3 +728,20 @@ class IPsecStrongswanDeviceDriverDVR(IPSecDeviceDVR):
               ipsec_process=strongswan_ipsec.StrongSwanProcess):
         super(IPsecStrongswanDeviceDriverDVR, self).setUp(driver,
                                                           ipsec_process)
+
+
+class IPsecFedoraStrongswanDeviceDriverLegacy(
+    IPsecStrongswanDeviceDriverLegacy):
+
+    def setUp(self, driver=fedora_strongswan_ipsec.FedoraStrongSwanDriver,
+              ipsec_process=fedora_strongswan_ipsec.FedoraStrongSwanProcess):
+        super(IPsecFedoraStrongswanDeviceDriverLegacy,
+              self).setUp(driver, ipsec_process)
+
+
+class IPsecFedoraStrongswanDeviceDriverDVR(IPSecDeviceDVR):
+
+    def setUp(self, driver=fedora_strongswan_ipsec.FedoraStrongSwanDriver,
+              ipsec_process=fedora_strongswan_ipsec.FedoraStrongSwanProcess):
+        super(IPsecFedoraStrongswanDeviceDriverDVR, self).setUp(driver,
+                                                                ipsec_process)