path: root/vswitches/ovs.py

# Copyright 2015-2016 Intel Corporation.
#
# 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.

"""VSPERF Open vSwitch base class
"""

import logging
import os
import pexpect
import re
import time

from conf import settings
from src.ovs import OFBridge, flow_key, flow_match
from tools import tasks
from vswitches.vswitch import IVSwitch

_OVS_VAR_DIR = settings.getValue('OVS_VAR_DIR')
_OVS_ETC_DIR = settings.getValue('OVS_ETC_DIR')


class IVSwitchOvs(IVSwitch, tasks.Process):
    """Open vSwitch base class implementation

    The method docstrings document only considerations specific to this
    implementation. For generic information of the nature of the methods,
    see the interface.
    """
    _logfile = os.path.join(settings.getValue('LOG_DIR'), settings.getValue('LOG_FILE_VSWITCHD'))
    _ovsdb_pidfile_path = os.path.join(settings.getValue('LOG_DIR'), "ovsdb_pidfile.pid")
    _vswitchd_pidfile_path = os.path.join(settings.getValue('LOG_DIR'), "vswitchd_pidfile.pid")
    _proc_name = 'ovs-vswitchd'

    def __init__(self):
        """See IVswitch for general description
        """
        self._logger = logging.getLogger(__name__)
        self._expect = None
        self._timeout = 30
        self._bridges = {}
        self._vswitchd_args = ['--pidfile=' + self._vswitchd_pidfile_path,
                               '--overwrite-pidfile', '--log-file=' + self._logfile]
        self._cmd = []
        self._cmd_template = ['sudo', '-E', os.path.join(settings.getValue('OVS_DIR'),
                                                         'vswitchd', 'ovs-vswitchd')]

    def start(self):
        """ Start ``ovsdb-server`` and ``ovs-vswitchd`` instance.

        :raises: pexpect.EOF, pexpect.TIMEOUT
        """
        self._logger.info("Starting vswitchd...")

        self._cmd = self._cmd_template + self._vswitchd_args

        # DB must be started before vswitchd
        self._reset_ovsdb()
        self._start_ovsdb()

        # DB must be up before vswitchd config is altered or vswitchd started
        time.sleep(3)

        self.configure()

        try:
            tasks.Process.start(self)
            self.relinquish()
        except (pexpect.EOF, pexpect.TIMEOUT) as exc:
            logging.error("Exception during VSwitch start.")
            self._kill_ovsdb()
            raise exc

        self._logger.info("Vswitchd...Started.")

    def configure(self):
        """ Configure vswitchd through ovsdb if needed
        """
        pass

    def stop(self):
        """See IVswitch for general description
        """
        self._logger.info("Terminating vswitchd...")
        self.kill()
        self._logger.info("Vswitchd...Terminated.")

    def add_switch(self, switch_name, params=None):
        """See IVswitch for general description
        """
        bridge = OFBridge(switch_name)
        bridge.create(params)
        bridge.set_db_attribute('Open_vSwitch', '.',
                                'other_config:max-idle',
                                settings.getValue('VSWITCH_FLOW_TIMEOUT'))
        self._bridges[switch_name] = bridge

    def del_switch(self, switch_name):
        """See IVswitch for general description
        """
        bridge = self._bridges[switch_name]
        self._bridges.pop(switch_name)
        bridge.destroy()

    def add_phy_port(self, switch_name):
        """See IVswitch for general description
        """
        raise NotImplementedError

    def add_vport(self, switch_name):
        """See IVswitch for general description
        """
        raise NotImplementedError

    def add_tunnel_port(self, switch_name, remote_ip, tunnel_type='vxlan', params=None):
        """Creates tunneling port
        """
        bridge = self._bridges[switch_name]
        pcount = str(self._get_port_count('type=' + tunnel_type))
        port_name = tunnel_type + pcount
        local_params = ['--', 'set', 'Interface', port_name,
                        'type=' + tunnel_type,
                        'options:remote_ip=' + remote_ip]

        if params is not None:
            local_params = local_params + params

        of_port = bridge.add_port(port_name, local_params)
        return (port_name, of_port)

    def get_ports(self, switch_name):
        """See IVswitch for general description
        """
        bridge = self._bridges[switch_name]
        ports = list(bridge.get_ports().items())
        return [(name, of_port) for (name, (of_port, _)) in ports]

    def del_port(self, switch_name, port_name):
        """See IVswitch for general description
        """
        bridge = self._bridges[switch_name]
        bridge.del_port(port_name)

    def add_flow(self, switch_name, flow, cache='off'):
        """See IVswitch for general description
        """
        bridge = self._bridges[switch_name]
        bridge.add_flow(flow, cache=cache)

    def del_flow(self, switch_name, flow=None):
        """See IVswitch for general description
        """
        flow = flow or {}
        bridge = self._bridges[switch_name]
        bridge.del_flow(flow)

    def dump_flows(self, switch_name):
        """See IVswitch for general description
        """
        bridge = self._bridges[switch_name]
        bridge.dump_flows()

    def add_route(self, switch_name, network, destination):
        """See IVswitch for general description
        """
        bridge = self._bridges[switch_name]
        bridge.add_route(network, destination)

    def set_tunnel_arp(self, ip_addr, mac_addr, switch_name):
        """See IVswitch for general description
        """
        bridge = self._bridges[switch_name]
        bridge.set_tunnel_arp(ip_addr, mac_addr, switch_name)

    def _get_port_count(self, param):
        """Returns the number of ports having a certain parameter
        """
        cnt = 0
        for k in self._bridges:
            pparams = [c for (_, (_, c)) in list(self._bridges[k].get_ports().items())]
            phits = [i for i in pparams if param in i]
            cnt += len(phits)

        if cnt is None:
            cnt = 0
        return cnt

    def disable_stp(self, switch_name):
        """
        Disable stp protocol on the bridge
        :param switch_name: bridge to disable stp
        :return: None
        """
        bridge = self._bridges[switch_name]
        bridge.set_stp(False)
        self._logger.info('Sleeping for 50 secs to allow stp to stop.')
        time.sleep(50)  # needs time to disable

    def enable_stp(self, switch_name):
        """
        Enable stp protocol on the bridge
        :param switch_name: bridge to enable stp
        :return: None
        """
        bridge = self._bridges[switch_name]
        bridge.set_stp(True)
        self._logger.info('Sleeping for 50 secs to allow stp to start.')
        time.sleep(50)  # needs time to enable

    def disable_rstp(self, switch_name):
        """
        Disable rstp on the bridge
        :param switch_name: bridge to disable rstp
        :return: None
        """
        bridge = self._bridges[switch_name]
        bridge.set_rstp(False)
        self._logger.info('Sleeping for 15 secs to allow rstp to stop.')
        time.sleep(15)  # needs time to disable

    def enable_rstp(self, switch_name):
        """
        Enable rstp on the bridge
        :param switch_name: bridge to enable rstp
        :return: None
        """
        bridge = self._bridges[switch_name]
        bridge.set_rstp(True)
        self._logger.info('Sleeping for 15 secs to allow rstp to start.')
        time.sleep(15)  # needs time to enable

    def kill(self, signal='-15', sleep=10):
        """Kill ``ovs-vswitchd`` and ``ovs-ovsdb`` instances if they are alive.

        :returns: None
        """
        if os.path.isfile(self._vswitchd_pidfile_path):
            self._logger.info('Killing ovs-vswitchd...')
            with open(self._vswitchd_pidfile_path, "r") as pidfile:
                vswitchd_pid = pidfile.read().strip()
                tasks.terminate_task(vswitchd_pid, logger=self._logger)

        self._kill_ovsdb()  # ovsdb must be killed after vswitchd

        # just for case, that sudo envelope has not been terminated yet
        tasks.Process.kill(self, signal, sleep)

    # helper functions

    def _reset_ovsdb(self):
        """Reset system for 'ovsdb'.

        :returns: None
        """
        self._logger.info('Resetting system after last run...')

        tasks.run_task(['sudo', 'rm', '-rf', _OVS_VAR_DIR], self._logger)
        tasks.run_task(['sudo', 'mkdir', '-p', _OVS_VAR_DIR], self._logger)
        tasks.run_task(['sudo', 'rm', '-rf', _OVS_ETC_DIR], self._logger)
        tasks.run_task(['sudo', 'mkdir', '-p', _OVS_ETC_DIR], self._logger)

        tasks.run_task(['sudo', 'rm', '-f',
                        os.path.join(_OVS_ETC_DIR, 'conf.db')],
                       self._logger)

        self._logger.info('System reset after last run.')

    def _start_ovsdb(self):
        """Start ``ovsdb-server`` instance.

        :returns: None
        """
        ovsdb_tool_bin = os.path.join(
            settings.getValue('OVS_DIR'), 'ovsdb', 'ovsdb-tool')
        tasks.run_task(['sudo', ovsdb_tool_bin, 'create',
                        os.path.join(_OVS_ETC_DIR, 'conf.db'),
                        os.path.join(settings.getValue('OVS_DIR'), 'vswitchd',
                                     'vswitch.ovsschema')],
                       self._logger,
                       'Creating ovsdb configuration database...')

        ovsdb_server_bin = os.path.join(
            settings.getValue('OVS_DIR'), 'ovsdb', 'ovsdb-server')

        tasks.run_background_task(
            ['sudo', ovsdb_server_bin,
             '--remote=punix:%s' % os.path.join(_OVS_VAR_DIR, 'db.sock'),
             '--remote=db:Open_vSwitch,Open_vSwitch,manager_options',
             '--pidfile=' + self._ovsdb_pidfile_path, '--overwrite-pidfile'],
            self._logger,
            'Starting ovsdb-server...')

    def _kill_ovsdb(self):
        """Kill ``ovsdb-server`` instance.

        :returns: None
        """
        if os.path.isfile(self._ovsdb_pidfile_path):
            with open(self._ovsdb_pidfile_path, "r") as pidfile:
                ovsdb_pid = pidfile.read().strip()

            self._logger.info("Killing ovsdb with pid: " + ovsdb_pid)

            if ovsdb_pid:
                tasks.terminate_task(ovsdb_pid, logger=self._logger)

    @staticmethod
    def get_db_sock_path():
        """Method returns location of db.sock file

        :returns: path to db.sock file.
        """
        return os.path.join(_OVS_VAR_DIR, 'db.sock')

    #
    # validate methods required for integration testcases
    #

    def validate_add_switch(self, result, switch_name, params=None):
        """Validate - Create a new logical switch with no ports
        """
        bridge = self._bridges[switch_name]
        output = bridge.run_vsctl(['show'], check_error=True)
        assert not output[1]  # there shouldn't be any stderr, but in case
        assert re.search('Bridge ["\']?%s["\']?' % switch_name, output[0]) is not None
        return True

    def validate_del_switch(self, result, switch_name):
        """Validate removal of switch
        """
        bridge = OFBridge('tmp')
        output = bridge.run_vsctl(['show'], check_error=True)
        assert not output[1]  # there shouldn't be any stderr, but in case
        assert re.search('Bridge ["\']?%s["\']?' % switch_name, output[0]) is None
        return True

    def validate_add_phy_port(self, result, switch_name):
        """ Validate that physical port was added to bridge.
        """
        bridge = self._bridges[switch_name]
        output = bridge.run_vsctl(['show'], check_error=True)
        assert not output[1]  # there shouldn't be any stderr, but in case
        assert re.search('Port ["\']?%s["\']?' % result[0], output[0]) is not None
        assert re.search('Interface ["\']?%s["\']?' % result[0], output[0]) is not None
        return True

    def validate_add_vport(self, result, switch_name):
        """ Validate that virtual port was added to bridge.
        """
        return self.validate_add_phy_port(result, switch_name)

    def validate_del_port(self, result, switch_name, port_name):
        """ Validate that port_name was removed from bridge.
        """
        bridge = self._bridges[switch_name]
        output = bridge.run_vsctl(['show'], check_error=True)
        assert not output[1]  # there shouldn't be any stderr, but in case
        assert 'Port "%s"' % port_name not in output[0]
        return True

    def validate_add_flow(self, result, switch_name, flow, cache='off'):
        """ Validate insertion of the flow into the switch
        """
        if 'idle_timeout' in flow:
            del(flow['idle_timeout'])

        # Note: it should be possible to call `ovs-ofctl dump-flows switch flow`
        # to verify flow insertion, but it doesn't accept the same flow syntax
        # as add-flow, so we have to compare it the hard way

        # get dump of flows and compare them one by one
        flow_src = flow_key(flow)
        bridge = self._bridges[switch_name]
        output = bridge.run_ofctl(['dump-flows', switch_name], check_error=True)
        for flow_dump in output[0].split('\n'):
            if flow_match(flow_dump, flow_src):
                # flow was added correctly
                return True
        return False

    def validate_del_flow(self, result, switch_name, flow=None):
        """ Validate removal of the flow
        """
        if not flow:
            # what else we can do?
            return True
        return not self.validate_add_flow(result, switch_name, flow)

    def validate_dump_flows(self, result, switch_name):
        """ Validate call of flow dump
        """
        return True

    def validate_disable_rstp(self, result, switch_name):
        """ Validate rstp disable
        """
        bridge = self._bridges[switch_name]
        return 'rstp_enable         : false' in ''.join(bridge.bridge_info())

    def validate_enable_rstp(self, result, switch_name):
        """ Validate rstp enable
        """
        bridge = self._bridges[switch_name]
        return 'rstp_enable         : true' in ''.join(bridge.bridge_info())

    def validate_disable_stp(self, result, switch_name):
        """ Validate stp disable
        """
        bridge = self._bridges[switch_name]
        return 'stp_enable          : false' in ''.join(bridge.bridge_info())

    def validate_enable_stp(self, result, switch_name):
        """ Validate stp enable
        """
        bridge = self._bridges[switch_name]
        return 'stp_enable          : true' in ''.join(bridge.bridge_info())