openstack/os-vif
Code Issues Proposed changes

ovs: convert over to use privsep module

Browse Source 
Instead of relying on root wrap, convert the openvswitch
network code to use the privsep module to run privileged
actions.

Change-Id: I45208c683fadf97ebcc46e08e2cc9781ff6eedb0
This commit is contained in:
Daniel P. Berrange 2016-03-02 11:44:57 +00:00
parent 48d9e6464a
commit 3f60c8e3f7
3 changed files with 67 additions and 46 deletions
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52
vif_plug_ovs/linux_net.py
View File

@ -27,6 +27,7 @@ from oslo_utils import excutils
from vif_plug_ovs import exception
from vif_plug_ovs.i18n import _LE
from vif_plug_ovs import privsep
LOG = logging.getLogger(__name__)
@ -37,13 +38,14 @@ def _ovs_vsctl(args, timeout=None):
full_args += ['--timeout=%s' % timeout]
full_args += args
try:
return processutils.execute(*full_args, run_as_root=True)
return processutils.execute(*full_args)
except Exception as e:
LOG.error(_LE("Unable to execute %(cmd)s. Exception: %(exception)s"),
{'cmd': full_args, 'exception': e})
raise exception.AgentError(method=full_args)
@privsep.vif_plug.entrypoint
def create_ovs_vif_port(bridge, dev, iface_id, mac, instance_id, mtu,
timeout=None):
_ovs_vsctl(['--', '--if-exists', 'del-port', dev, '--',
@ -57,10 +59,11 @@ def create_ovs_vif_port(bridge, dev, iface_id, mac, instance_id, mtu,
_set_device_mtu(dev, mtu)
@privsep.vif_plug.entrypoint
def delete_ovs_vif_port(bridge, dev, timeout=None):
_ovs_vsctl(['--', '--if-exists', 'del-port', bridge, dev],
timeout=timeout)
delete_net_dev(dev)
_delete_net_dev(dev)
def device_exists(device):
@ -68,74 +71,65 @@ def device_exists(device):
return os.path.exists('/sys/class/net/%s' % device)
def delete_net_dev(dev):
def _delete_net_dev(dev):
"""Delete a network device only if it exists."""
if device_exists(dev):
try:
processutils.execute('ip', 'link', 'delete', dev,
check_exit_code=[0, 2, 254],
run_as_root=True)
check_exit_code=[0, 2, 254])
LOG.debug("Net device removed: '%s'", dev)
except processutils.ProcessExecutionError:
with excutils.save_and_reraise_exception():
LOG.error(_LE("Failed removing net device: '%s'"), dev)
@privsep.vif_plug.entrypoint
def create_veth_pair(dev1_name, dev2_name, mtu):
"""Create a pair of veth devices with the specified names,
deleting any previous devices with those names.
"""
for dev in [dev1_name, dev2_name]:
delete_net_dev(dev)
_delete_net_dev(dev)
processutils.execute('ip', 'link', 'add', dev1_name,
'type', 'veth', 'peer', 'name', dev2_name,
run_as_root=True)
'type', 'veth', 'peer', 'name', dev2_name)
for dev in [dev1_name, dev2_name]:
processutils.execute('ip', 'link', 'set', dev, 'up',
run_as_root=True)
processutils.execute('ip', 'link', 'set', dev, 'up')
processutils.execute('ip', 'link', 'set', dev, 'promisc', 'on')
_set_device_mtu(dev, mtu)
@privsep.vif_plug.entrypoint
def ensure_bridge(bridge):
if not device_exists(bridge):
processutils.execute('brctl', 'addbr', bridge,
run_as_root=True)
processutils.execute('brctl', 'setfd', bridge, 0,
run_as_root=True)
processutils.execute('brctl', 'stp', bridge, 'off',
run_as_root=True)
processutils.execute('brctl', 'addbr', bridge)
processutils.execute('brctl', 'setfd', bridge, 0)
processutils.execute('brctl', 'stp', bridge, 'off')
syspath = '/sys/class/net/%s/bridge/multicast_snooping'
syspath = syspath % bridge
processutils.execute('tee', syspath, process_input='0',
check_exit_code=[0, 1],
run_as_root=True)
check_exit_code=[0, 1])
disv6 = ('/proc/sys/net/ipv6/conf/%s/disable_ipv6' %
bridge)
if os.path.exists(disv6):
processutils.execute('tee',
disv6,
process_input='1',
run_as_root=True,
check_exit_code=[0, 1])
@privsep.vif_plug.entrypoint
def delete_bridge(bridge, dev):
if device_exists(bridge):
processutils.execute('brctl', 'delif', bridge, dev,
run_as_root=True)
processutils.execute('ip', 'link', 'set', bridge, 'down',
run_as_root=True)
processutils.execute('brctl', 'delbr', bridge,
run_as_root=True)
processutils.execute('brctl', 'delif', bridge, dev)
processutils.execute('ip', 'link', 'set', bridge, 'down')
processutils.execute('brctl', 'delbr', bridge)
@privsep.vif_plug.entrypoint
def add_bridge_port(bridge, dev):
processutils.execute('ip', 'link', 'set', bridge, 'up',
run_as_root=True)
processutils.execute('brctl', 'addif', bridge, dev,
run_as_root=True)
processutils.execute('ip', 'link', 'set', bridge, 'up')
processutils.execute('brctl', 'addif', bridge, dev)
def _set_device_mtu(dev, mtu):

24
vif_plug_ovs/privsep.py Normal file
View File

@ -0,0 +1,24 @@
#
# Copyright (C) 2016 Red Hat, 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 oslo_privsep import capabilities as c
from oslo_privsep import priv_context
vif_plug = priv_context.PrivContext(
"vif_plug_ovs",
cfg_section="vif_plug_ovs_privileged",
pypath=__name__ + ".vif_plug",
capabilities=[c.CAP_NET_ADMIN],
)

37
vif_plug_ovs/tests/test_linux_net.py
View File

@ -19,6 +19,7 @@ import testtools
from oslo_concurrency import processutils
from vif_plug_ovs import linux_net
from vif_plug_ovs import privsep
if six.PY2:
@ -32,6 +33,11 @@ else:
class LinuxNetTest(testtools.TestCase):
def setUp(self):
super(LinuxNetTest, self).setUp()
privsep.vif_plug.set_client_mode(False)
@mock.patch.object(processutils, "execute")
@mock.patch.object(linux_net, "device_exists", return_value=True)
def test_ensure_bridge_exists(self, mock_dev_exists, mock_execute):
@ -50,12 +56,11 @@ class LinuxNetTest(testtools.TestCase):
linux_net.ensure_bridge("br0")
self.assertEqual(mock_execute.mock_calls, [
mock.call('brctl', 'addbr', 'br0', run_as_root=True),
mock.call('brctl', 'setfd', 'br0', 0, run_as_root=True),
mock.call('brctl', 'stp', 'br0', "off", run_as_root=True),
mock.call('brctl', 'addbr', 'br0'),
mock.call('brctl', 'setfd', 'br0', 0),
mock.call('brctl', 'stp', 'br0', "off"),
mock.call('tee', '/sys/class/net/br0/bridge/multicast_snooping',
check_exit_code=[0, 1], process_input='0',
run_as_root=True),
check_exit_code=[0, 1], process_input='0'),
])
self.assertEqual(mock_dev_exists.mock_calls, [
mock.call("br0")
@ -69,15 +74,13 @@ class LinuxNetTest(testtools.TestCase):
linux_net.ensure_bridge("br0")
self.assertEqual(mock_execute.mock_calls, [
mock.call('brctl', 'addbr', 'br0', run_as_root=True),
mock.call('brctl', 'setfd', 'br0', 0, run_as_root=True),
mock.call('brctl', 'stp', 'br0', "off", run_as_root=True),
mock.call('brctl', 'addbr', 'br0'),
mock.call('brctl', 'setfd', 'br0', 0),
mock.call('brctl', 'stp', 'br0', "off"),
mock.call('tee', '/sys/class/net/br0/bridge/multicast_snooping',
check_exit_code=[0, 1], process_input='0',
run_as_root=True),
check_exit_code=[0, 1], process_input='0'),
mock.call('tee', '/proc/sys/net/ipv6/conf/br0/disable_ipv6',
check_exit_code=[0, 1], process_input='1',
run_as_root=True),
check_exit_code=[0, 1], process_input='1'),
])
self.assertEqual(mock_dev_exists.mock_calls, [
mock.call("br0")
@ -99,9 +102,9 @@ class LinuxNetTest(testtools.TestCase):
linux_net.delete_bridge("br0", "vnet1")
self.assertEqual(mock_execute.mock_calls, [
mock.call('brctl', 'delif', 'br0', 'vnet1', run_as_root=True),
mock.call('ip', 'link', 'set', 'br0', 'down', run_as_root=True),
mock.call('brctl', 'delbr', 'br0', run_as_root=True),
mock.call('brctl', 'delif', 'br0', 'vnet1'),
mock.call('ip', 'link', 'set', 'br0', 'down'),
mock.call('brctl', 'delbr', 'br0'),
])
self.assertEqual(mock_dev_exists.mock_calls, [
mock.call("br0")
@ -112,6 +115,6 @@ class LinuxNetTest(testtools.TestCase):
linux_net.add_bridge_port("br0", "vnet1")
self.assertEqual(mock_execute.mock_calls, [
mock.call('ip', 'link', 'set', 'br0', 'up', run_as_root=True),
mock.call('brctl', 'addif', 'br0', 'vnet1', run_as_root=True),
mock.call('ip', 'link', 'set', 'br0', 'up'),
mock.call('brctl', 'addif', 'br0', 'vnet1'),
])