OpenStack Networking (Neutron)
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
neutron/neutron/agent/linux/ip_lib.py

567 lines
18 KiB

# Copyright 2012 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 netaddr
from oslo.config import cfg
from neutron.agent.linux import utils
from neutron.common import exceptions
OPTS = [
cfg.BoolOpt('ip_lib_force_root',
default=False,
help=_('Force ip_lib calls to use the root helper')),
]
LOOPBACK_DEVNAME = 'lo'
# NOTE(ethuleau): depend of the version of iproute2, the vlan
# interface details vary.
VLAN_INTERFACE_DETAIL = ['vlan protocol 802.1q',
'vlan protocol 802.1Q',
'vlan id']
class SubProcessBase(object):
def __init__(self, root_helper=None, namespace=None):
self.root_helper = root_helper
self.namespace = namespace
try:
self.force_root = cfg.CONF.ip_lib_force_root
except cfg.NoSuchOptError:
# Only callers that need to force use of the root helper
# need to register the option.
self.force_root = False
def _run(self, options, command, args):
if self.namespace:
return self._as_root(options, command, args)
elif self.force_root:
# Force use of the root helper to ensure that commands
# will execute in dom0 when running under XenServer/XCP.
return self._execute(options, command, args, self.root_helper)
else:
return self._execute(options, command, args)
def _as_root(self, options, command, args, use_root_namespace=False):
if not self.root_helper:
raise exceptions.SudoRequired()
namespace = self.namespace if not use_root_namespace else None
return self._execute(options,
command,
args,
self.root_helper,
namespace)
@classmethod
def _execute(cls, options, command, args, root_helper=None,
namespace=None):
opt_list = ['-%s' % o for o in options]
if namespace:
ip_cmd = ['ip', 'netns', 'exec', namespace, 'ip']
else:
ip_cmd = ['ip']
return utils.execute(ip_cmd + opt_list + [command] + list(args),
root_helper=root_helper)
class IPWrapper(SubProcessBase):
def __init__(self, root_helper=None, namespace=None):
super(IPWrapper, self).__init__(root_helper=root_helper,
namespace=namespace)
self.netns = IpNetnsCommand(self)
def device(self, name):
return IPDevice(name, self.root_helper, self.namespace)
def get_devices(self, exclude_loopback=False):
retval = []
output = self._execute(['o', 'd'], 'link', ('list',),
self.root_helper, self.namespace)
for line in output.split('\n'):
if '<' not in line:
continue
tokens = line.split(' ', 2)
if len(tokens) == 3:
if any(v in tokens[2] for v in VLAN_INTERFACE_DETAIL):
delimiter = '@'
else:
delimiter = ':'
name = tokens[1].rpartition(delimiter)[0].strip()
if exclude_loopback and name == LOOPBACK_DEVNAME:
continue
retval.append(IPDevice(name,
self.root_helper,
self.namespace))
return retval
def add_tuntap(self, name, mode='tap'):
self._as_root('', 'tuntap', ('add', name, 'mode', mode))
return IPDevice(name, self.root_helper, self.namespace)
def add_veth(self, name1, name2, namespace2=None):
args = ['add', name1, 'type', 'veth', 'peer', 'name', name2]
if namespace2 is None:
namespace2 = self.namespace
else:
self.ensure_namespace(namespace2)
args += ['netns', namespace2]
self._as_root('', 'link', tuple(args))
return (IPDevice(name1, self.root_helper, self.namespace),
IPDevice(name2, self.root_helper, namespace2))
def ensure_namespace(self, name):
if not self.netns.exists(name):
ip = self.netns.add(name)
lo = ip.device(LOOPBACK_DEVNAME)
lo.link.set_up()
else:
ip = IPWrapper(self.root_helper, name)
return ip
def namespace_is_empty(self):
return not self.get_devices(exclude_loopback=True)
def garbage_collect_namespace(self):
"""Conditionally destroy the namespace if it is empty."""
if self.namespace and self.netns.exists(self.namespace):
if self.namespace_is_empty():
self.netns.delete(self.namespace)
return True
return False
def add_device_to_namespace(self, device):
if self.namespace:
device.link.set_netns(self.namespace)
def add_vxlan(self, name, vni, group=None, dev=None, ttl=None, tos=None,
local=None, port=None, proxy=False):
cmd = ['add', name, 'type', 'vxlan', 'id', vni]
if group:
cmd.extend(['group', group])
if dev:
cmd.extend(['dev', dev])
if ttl:
cmd.extend(['ttl', ttl])
if tos:
cmd.extend(['tos', tos])
if local:
cmd.extend(['local', local])
if proxy:
cmd.append('proxy')
# tuple: min,max
if port and len(port) == 2:
cmd.extend(['port', port[0], port[1]])
elif port:
raise exceptions.NetworkVxlanPortRangeError(vxlan_range=port)
self._as_root('', 'link', cmd)
return (IPDevice(name, self.root_helper, self.namespace))
@classmethod
def get_namespaces(cls, root_helper):
output = cls._execute('', 'netns', ('list',), root_helper=root_helper)
return [l.strip() for l in output.split('\n')]
class IpRule(IPWrapper):
def add_rule_from(self, ip, table, rule_pr):
args = ['add', 'from', ip, 'lookup', table, 'priority', rule_pr]
ip = self._as_root('', 'rule', tuple(args))
return ip
def delete_rule_priority(self, rule_pr):
args = ['del', 'priority', rule_pr]
ip = self._as_root('', 'rule', tuple(args))
return ip
class IPDevice(SubProcessBase):
def __init__(self, name, root_helper=None, namespace=None):
super(IPDevice, self).__init__(root_helper=root_helper,
namespace=namespace)
self.name = name
self.link = IpLinkCommand(self)
self.addr = IpAddrCommand(self)
self.route = IpRouteCommand(self)
self.neigh = IpNeighCommand(self)
def __eq__(self, other):
return (other is not None and self.name == other.name
and self.namespace == other.namespace)
def __str__(self):
return self.name
class IpCommandBase(object):
COMMAND = ''
def __init__(self, parent):
self._parent = parent
def _run(self, *args, **kwargs):
return self._parent._run(kwargs.get('options', []), self.COMMAND, args)
def _as_root(self, *args, **kwargs):
return self._parent._as_root(kwargs.get('options', []),
self.COMMAND,
args,
kwargs.get('use_root_namespace', False))
class IpDeviceCommandBase(IpCommandBase):
@property
def name(self):
return self._parent.name
class IpLinkCommand(IpDeviceCommandBase):
COMMAND = 'link'
def set_address(self, mac_address):
self._as_root('set', self.name, 'address', mac_address)
def set_mtu(self, mtu_size):
self._as_root('set', self.name, 'mtu', mtu_size)
def set_up(self):
self._as_root('set', self.name, 'up')
def set_down(self):
self._as_root('set', self.name, 'down')
def set_netns(self, namespace):
self._as_root('set', self.name, 'netns', namespace)
self._parent.namespace = namespace
def set_name(self, name):
self._as_root('set', self.name, 'name', name)
self._parent.name = name
def set_alias(self, alias_name):
self._as_root('set', self.name, 'alias', alias_name)
def delete(self):
self._as_root('delete', self.name)
@property
def address(self):
return self.attributes.get('link/ether')
@property
def state(self):
return self.attributes.get('state')
@property
def mtu(self):
return self.attributes.get('mtu')
@property
def qdisc(self):
return self.attributes.get('qdisc')
@property
def qlen(self):
return self.attributes.get('qlen')
@property
def alias(self):
return self.attributes.get('alias')
@property
def attributes(self):
return self._parse_line(self._run('show', self.name, options='o'))
def _parse_line(self, value):
if not value:
return {}
device_name, settings = value.replace("\\", '').split('>', 1)
tokens = settings.split()
keys = tokens[::2]
values = [int(v) if v.isdigit() else v for v in tokens[1::2]]
retval = dict(zip(keys, values))
return retval
class IpAddrCommand(IpDeviceCommandBase):
COMMAND = 'addr'
def add(self, ip_version, cidr, broadcast, scope='global'):
self._as_root('add',
cidr,
'brd',
broadcast,
'scope',
scope,
'dev',
self.name,
options=[ip_version])
def delete(self, ip_version, cidr):
self._as_root('del',
cidr,
'dev',
self.name,
options=[ip_version])
def flush(self):
self._as_root('flush', self.name)
def list(self, scope=None, to=None, filters=None):
if filters is None:
filters = []
retval = []
if scope:
filters += ['scope', scope]
if to:
filters += ['to', to]
for line in self._run('show', self.name, *filters).split('\n'):
line = line.strip()
if not line.startswith('inet'):
continue
parts = line.split()
if parts[0] == 'inet6':
version = 6
scope = parts[3]
broadcast = '::'
else:
version = 4
if parts[2] == 'brd':
broadcast = parts[3]
scope = parts[5]
else:
# sometimes output of 'ip a' might look like:
# inet 192.168.100.100/24 scope global eth0
# and broadcast needs to be calculated from CIDR
broadcast = str(netaddr.IPNetwork(parts[1]).broadcast)
scope = parts[3]
retval.append(dict(cidr=parts[1],
broadcast=broadcast,
scope=scope,
ip_version=version,
dynamic=('dynamic' == parts[-1])))
return retval
class IpRouteCommand(IpDeviceCommandBase):
COMMAND = 'route'
def add_gateway(self, gateway, metric=None, table=None):
args = ['replace', 'default', 'via', gateway]
if metric:
args += ['metric', metric]
args += ['dev', self.name]
if table:
args += ['table', table]
self._as_root(*args)
def delete_gateway(self, gateway=None, table=None):
args = ['del', 'default']
if gateway:
args += ['via', gateway]
args += ['dev', self.name]
if table:
args += ['table', table]
self._as_root(*args)
def list_onlink_routes(self):
def iterate_routes():
output = self._run('list', 'dev', self.name, 'scope', 'link')
for line in output.split('\n'):
line = line.strip()
if line and not line.count('src'):
yield line
return [x for x in iterate_routes()]
def add_onlink_route(self, cidr):
self._as_root('replace', cidr, 'dev', self.name, 'scope', 'link')
def delete_onlink_route(self, cidr):
self._as_root('del', cidr, 'dev', self.name, 'scope', 'link')
def get_gateway(self, scope=None, filters=None):
if filters is None:
filters = []
retval = None
if scope:
filters += ['scope', scope]
route_list_lines = self._run('list', 'dev', self.name,
*filters).split('\n')
default_route_line = next((x.strip() for x in
route_list_lines if
x.strip().startswith('default')), None)
if default_route_line:
gateway_index = 2
parts = default_route_line.split()
retval = dict(gateway=parts[gateway_index])
if 'metric' in parts:
metric_index = parts.index('metric') + 1
retval.update(metric=int(parts[metric_index]))
return retval
def pullup_route(self, interface_name):
"""Ensures that the route entry for the interface is before all
others on the same subnet.
"""
device_list = []
device_route_list_lines = self._run('list', 'proto', 'kernel',
'dev', interface_name).split('\n')
for device_route_line in device_route_list_lines:
try:
subnet = device_route_line.split()[0]
except Exception:
continue
subnet_route_list_lines = self._run('list', 'proto', 'kernel',
'match', subnet).split('\n')
for subnet_route_line in subnet_route_list_lines:
i = iter(subnet_route_line.split())
while(i.next() != 'dev'):
pass
device = i.next()
try:
while(i.next() != 'src'):
pass
src = i.next()
except Exception:
src = ''
if device != interface_name:
device_list.append((device, src))
else:
break
for (device, src) in device_list:
self._as_root('del', subnet, 'dev', device)
if (src != ''):
self._as_root('append', subnet, 'proto', 'kernel',
'src', src, 'dev', device)
else:
self._as_root('append', subnet, 'proto', 'kernel',
'dev', device)
def add_route(self, cidr, ip, table=None):
args = ['replace', cidr, 'via', ip, 'dev', self.name]
if table:
args += ['table', table]
self._as_root(*args)
def delete_route(self, cidr, ip, table=None):
args = ['del', cidr, 'via', ip, 'dev', self.name]
if table:
args += ['table', table]
self._as_root(*args)
class IpNeighCommand(IpDeviceCommandBase):
COMMAND = 'neigh'
def add(self, ip_version, ip_address, mac_address):
self._as_root('replace',
ip_address,
'lladdr',
mac_address,
'nud',
'permanent',
'dev',
self.name,
options=[ip_version])
def delete(self, ip_version, ip_address, mac_address):
self._as_root('del',
ip_address,
'lladdr',
mac_address,
'dev',
self.name,
options=[ip_version])
class IpNetnsCommand(IpCommandBase):
COMMAND = 'netns'
def add(self, name):
self._as_root('add', name, use_root_namespace=True)
return IPWrapper(self._parent.root_helper, name)
def delete(self, name):
self._as_root('delete', name, use_root_namespace=True)
def execute(self, cmds, addl_env={}, check_exit_code=True):
if not self._parent.root_helper:
raise exceptions.SudoRequired()
ns_params = []
if self._parent.namespace:
ns_params = ['ip', 'netns', 'exec', self._parent.namespace]
env_params = []
if addl_env:
env_params = (['env'] +
['%s=%s' % pair for pair in addl_env.items()])
return utils.execute(
ns_params + env_params + list(cmds),
root_helper=self._parent.root_helper,
check_exit_code=check_exit_code)
def exists(self, name):
output = self._parent._execute('o', 'netns', ['list'])
for line in output.split('\n'):
if name == line.strip():
return True
return False
def device_exists(device_name, root_helper=None, namespace=None):
try:
address = IPDevice(device_name, root_helper, namespace).link.address
except RuntimeError:
return False
return bool(address)
def ensure_device_is_ready(device_name, root_helper=None, namespace=None):
dev = IPDevice(device_name, root_helper, namespace)
try:
# Ensure the device is up, even if it is already up. If the device
# doesn't exist, a RuntimeError will be raised.
dev.link.set_up()
except RuntimeError:
return False
return True
def iproute_arg_supported(command, arg, root_helper=None):
command += ['help']
stdout, stderr = utils.execute(command, root_helper=root_helper,
check_exit_code=False, return_stderr=True)
return any(arg in line for line in stderr.split('\n'))