ovn-docker-driver

#! /usr/bin/python
# Copyright (C) 2015 Nicira, 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.

import argparse
import atexit
import getpass
import json
import os
import re
import shlex
import subprocess
import sys
import time
import uuid

import ovs.dirs
import ovs.util
import ovs.daemon
import ovs.unixctl.server
import ovs.vlog

from neutronclient.v2_0 import client
from flask import Flask, jsonify
from flask import request, abort

app = Flask(__name__)
vlog = ovs.vlog.Vlog("ovn-docker-driver")

AUTH_STRATEGY = ""
AUTH_URL = ""
ENDPOINT_URL = ""
MODE = ""
OVN_BRIDGE = ""
PASSWORD = ""
PLUGIN_DIR = "/etc/docker/plugins"
PLUGIN_FILE = "/etc/docker/plugins/openvswitch.spec"
TENANT_ID = ""
USERNAME = ""
VIF_ID = ""


def call_popen(cmd):
    child = subprocess.Popen(cmd, stdout=subprocess.PIPE)
    output = child.communicate()
    if child.returncode:
        raise RuntimeError("Fatal error executing %s" % (cmd))
    if len(output) == 0 or output[0] == None:
        output = ""
    else:
        output = output[0].strip()
    return output


def call_prog(prog, args_list):
    cmd = [prog, "-vconsole:off"] + args_list
    return call_popen(cmd)


def ovs_vsctl(args):
    return call_prog("ovs-vsctl", shlex.split(args))


def cleanup():
    if os.path.isfile(PLUGIN_FILE):
        os.remove(PLUGIN_FILE)


def ovn_init_overlay():
    global OVN_BRIDGE
    OVN_BRIDGE = "br-int"
    br_list = ovs_vsctl("list-br").split()
    if OVN_BRIDGE not in br_list:
        ovs_vsctl("-- --may-exist add-br %s "
                  "-- br-set-external-id %s bridge-id %s "
                  "-- set bridge %s other-config:disable-in-band=true "
                  "-- set bridge %s fail-mode=secure"
                  % (OVN_BRIDGE, OVN_BRIDGE, OVN_BRIDGE, OVN_BRIDGE,
                     OVN_BRIDGE))

    global AUTH_STRATEGY, ENDPOINT_URL
    AUTH_STRATEGY = "noauth"
    endpoint_ip = ovs_vsctl("get Open_vSwitch . "
                            "external_ids:ipam").strip('"')
    if not endpoint_ip:
        sys.exit("ipam server's ip address not set")
    ENDPOINT_URL = "http://%s:9696/" % (endpoint_ip)

    ovs_vsctl("set open_vswitch . external_ids:ovn-bridge=%s "
              "external_ids:ovn-encap-type=geneve" % OVN_BRIDGE)


def ovn_init_underlay():
    global USERNAME, PASSWORD, TENANT_ID, AUTH_URL, AUTH_STRATEGY, VIF_ID

    VIF_ID = os.environ.get('OS_VIF_ID', '')
    if not VIF_ID:
        sys.exit("env OS_VIF_ID not set")
    USERNAME = os.environ.get('OS_USERNAME', '')
    if not USERNAME:
        sys.exit("env OS_USERNAME not set")
    TENANT_ID = os.environ.get('OS_TENANT_ID', '')
    if not TENANT_ID:
        sys.exit("env OS_TENANT_ID not set")
    AUTH_URL = os.environ.get('OS_AUTH_URL', '')
    if not AUTH_URL:
        sys.exit("env OS_AUTH_URL not set")
    AUTH_STRATEGY = "keystone"

    PASSWORD = os.environ.get('OS_PASSWORD', '')
    if not PASSWORD:
        PASSWORD = getpass.getpass()


def ovn_init(args):
    global MODE
    if args.underlay_mode:
        if not args.bridge:
            sys.exit("OVS bridge name not provided")
        global OVN_BRIDGE
        OVN_BRIDGE = args.bridge
        MODE = "underlay"
        ovn_init_underlay()
    else:
        MODE = "overlay"
        ovn_init_overlay()


def prepare():
    parser = argparse.ArgumentParser()
    parser.add_argument('--overlay-mode', action='store_true')
    parser.add_argument('--underlay-mode', action='store_true')
    parser.add_argument('--bridge', help="The Bridge to which containers "
                        "interfaces connect to.")

    ovs.vlog.add_args(parser)
    ovs.daemon.add_args(parser)
    args = parser.parse_args()
    ovs.vlog.handle_args(args)
    ovs.daemon.handle_args(args)
    ovn_init(args)

    if not os.path.isdir(PLUGIN_DIR):
        sys.exit("No docker plugin directory configured")

    ovs.daemon.daemonize()
    try:
        fo = open(PLUGIN_FILE, "w")
        fo.write("tcp://0.0.0.0:5000")
        fo.close()
    except Exception as e:
        ovs.util.ovs_fatal(0, "Failed to write to spec file (%s)" % str(e),
                           vlog)

    atexit.register(cleanup)


# curl -i -H 'Content-Type: application/json' -X POST
# http://localhost:5000/Plugin.Activate
@app.route('/Plugin.Activate', methods=['POST'])
def plugin_activate():
    return jsonify({"Implements": ["NetworkDriver"]})


def neutron_login():
    try:
        neutron = client.Client(username=USERNAME,
                                password=PASSWORD,
                                tenant_id=TENANT_ID,
                                auth_url=AUTH_URL,
                                endpoint_url=ENDPOINT_URL,
                                auth_strategy=AUTH_STRATEGY)
    except Exception as e:
        raise RuntimeError("Failed to login into Neutron(%s)" % str(e))
    return neutron


def get_networkuuid_by_name(neutron, name):
    param = {'fields': 'id', 'name': name}
    ret = neutron.list_networks(**param)
    if len(ret['networks']) > 1:
        raise RuntimeError("More than one network for the given name")
    elif len(ret['networks']) == 0:
        network = None
    else:
        network = ret['networks'][0]['id']
    return network


# curl -i -H 'Content-Type: application/json' -X POST -d
# '{"NetworkID":"dummy-network","Options":{"subnet":"192.168.1.0/24"}}'
# http://localhost:5000/NetworkDriver.CreateNetwork
@app.route('/NetworkDriver.CreateNetwork', methods=['POST'])
def create_network():
    # When IPAM is Neutron, we will have to create subnet separately
    # because Docker currently does not allow passing subnet information.

    if not request.data:
        abort(400)

    data = json.loads(request.data)

    # NetworkID will have docker generated network uuid and it
    # becomes 'name' in a neutron network record.
    network = data.get("NetworkID", "")
    if not network:
        abort(400)

    try:
        neutron = neutron_login()
    except Exception as e:
        error = "%s" % (str(e))
        return jsonify({'Err': error})

    try:
        if get_networkuuid_by_name(neutron, network):
            return jsonify({})
    except Exception as e:
        error = "%s" % (str(e))
        return jsonify({'Err': error})

    try:
        if MODE == "underlay":
            body = {'network': {'name': network, 'admin_state_up': True}}
        else:
            body = {'network': {'name': network,
                                'tenant_id': "admin",
                                'admin_state_up': True}}
        ret = neutron.create_network(body)
        network_id = ret['network']['id']
    except Exception as e:
        error = "Failed in neutron api call (%s)" % str(e)
        return jsonify({'Err': error})

    return jsonify({})


# curl -i -H 'Content-Type: application/json' -X POST -d
# {"NetworkID":"dummy-network"}
# http://localhost:5000/NetworkDriver.DeleteNetwork
@app.route('/NetworkDriver.DeleteNetwork', methods=['POST'])
def delete_network():
    if not request.data:
        abort(400)

    data = json.loads(request.data)

    nid = data.get("NetworkID", "")
    if not nid:
        abort(400)

    try:
        neutron = neutron_login()
    except Exception as e:
        error = "%s" % (str(e))
        return jsonify({'Err': error})

    network = get_networkuuid_by_name(neutron, nid)
    if not network:
        return jsonify({})

    try:
        neutron.delete_network(network)
    except Exception as e:
        error = "Failed in neutron api call (%s)" % str(e)
        return jsonify({'Err': error})

    return jsonify({})


def reserve_vlan():
    reserved_vlan = 0
    vlans = ovs_vsctl("--if-exists get Open_vSwitch . "
                      "external_ids:vlans").strip('"')
    if not vlans:
        reserved_vlan = 1
        ovs_vsctl("set Open_vSwitch . external_ids:vlans=%s" % reserved_vlan)
        return reserved_vlan

    vlan_set = str(vlans).split(',')

    for vlan in range(1, 4095):
        if str(vlan) not in vlan_set:
            vlan_set.append(str(vlan))
            reserved_vlan = vlan
            vlans = re.sub(r'[ \[\]\']', '', str(vlan_set))
            ovs_vsctl("set Open_vSwitch . external_ids:vlans=%s" % vlans)
            return reserved_vlan

    if not reserved_vlan:
        raise RuntimeError("No more vlans available on this host")


def unreserve_vlan(reserved_vlan):
    vlans = ovs_vsctl("--if-exists get Open_vSwitch . "
                      "external_ids:vlans").strip('"')
    if not vlans:
        return

    vlan_set = str(vlans).split(',')
    if str(reserved_vlan) not in vlan_set:
        return

    vlan_set.remove(str(reserved_vlan))
    vlans = re.sub(r'[ \[\]\']', '', str(vlan_set))
    if vlans:
        ovs_vsctl("set Open_vSwitch . external_ids:vlans=%s" % vlans)
    else:
        ovs_vsctl("remove Open_vSwitch . external_ids vlans")


def create_port_underlay(neutron, network, eid):
    reserved_vlan = reserve_vlan()
    body = {'port': {'network_id': network,
                     'binding:profile': {'parent_name': VIF_ID,
                                         'tag': int(reserved_vlan)},
                     'name': eid,
                     'admin_state_up': True}}

    try:
        ret = neutron.create_port(body)
        mac_address = ret['port']['mac_address']
        ip = "%s" % ret['port']['fixed_ips'][0]['ip_address']
    except Exception as e:
        unreserve_vlan(reserved_vlan)
        raise RuntimeError("Failed in creation of neutron port (%s)." % str(e))

    ovs_vsctl("set Open_vSwitch . external_ids:%s_vlan=%s"
              % (eid, reserved_vlan))

    return (mac_address, ip)


def create_port_overlay(neutron, network, eid):
    body = {'port': {'network_id': network,
                     'tenant_id': "admin",
                     'name': eid,
                     'admin_state_up': True}}

    ret = neutron.create_port(body)
    mac_address = ret['port']['mac_address']
    ip = "%s" % ret['port']['fixed_ips'][0]['ip_address']
    return (mac_address, ip)


def get_endpointuuid_by_name(neutron, name):
    param = {'fields': 'id', 'name': name}
    ret = neutron.list_ports(**param)
    if len(ret['ports']) > 1:
        raise RuntimeError("More than one endpoint for the given name")
    elif len(ret['ports']) == 0:
        endpoint = None
    else:
        endpoint = ret['ports'][0]['id']
    return endpoint


# curl -i -H 'Content-Type: application/json' -X POST -d
# '{"NetworkID":"dummy-network","EndpointID":"dummy-endpoint","Interfaces":[],"Options":{}}'
# http://localhost:5000/NetworkDriver.CreateEndpoint
@app.route('/NetworkDriver.CreateEndpoint', methods=['POST'])
def create_endpoint():
    if not request.data:
        abort(400)

    data = json.loads(request.data)

    nid = data.get("NetworkID", "")
    if not nid:
        abort(400)

    eid = data.get("EndpointID", "")
    if not eid:
        abort(400)

    interfaces = data.get("Interfaces", "")
    if interfaces:
        # If interfaces has record, the endpoint has already
        # been created.
        return jsonify({})

    try:
        neutron = neutron_login()
    except Exception as e:
        error = "%s" % (str(e))
        return jsonify({'Err': error})

    network = get_networkuuid_by_name(neutron, nid)
    if not network:
        error = "Failed to get neutron network record for (%s)" % (nid)
        return jsonify({'Err': error})

    try:
        ret = neutron.show_network(network)
        subnet = ret['network']['subnets'][0]
        if not subnet:
            raise RuntimeError("No subnet defined for the network.")
    except Exception as e:
        error = "Could not obtain network information.\n(%s)" % (str(e))
        return jsonify({'Err': error})

    try:
        ret = neutron.show_subnet(subnet)
        gateway_ip = ret['subnet']['gateway_ip']
        cidr = ret['subnet']['cidr']
        netmask = cidr.rsplit('/', 1)[1]
        if not netmask:
            raise RuntimeError("No cidr netmask found for subnet")
    except Exception as e:
        error = "Could not obtain subnet information (%s)" % (str(e))
        return jsonify({'Err': error})

    try:
        if MODE == "underlay":
            (mac_address, ip_address) = create_port_underlay(neutron, network,
                                                             eid)
        else:
            (mac_address, ip_address) = create_port_overlay(neutron, network,
                                                            eid)

    except Exception as e:
        error = "Failed in neutron port creation call (%s)" % (str(e))
        return jsonify({'Err': error})

    ip_address_and_mask = "%s/%s" % (ip_address, netmask)
    return jsonify({"Interfaces": [{
                                    "ID": 0,
                                    "Address": ip_address_and_mask,
                                    "AddressIPv6": None,
                                    "MacAddress": mac_address
                                    }]})


# curl -i -H 'Content-Type: application/json' -X POST -d
# '{"NetworkID":"dummy-network","EndpointID":"dummy-endpoint"}'
# http://localhost:5000/NetworkDriver.EndpointOperInfo
@app.route('/NetworkDriver.EndpointOperInfo', methods=['POST'])
def show_endpoint():
    if not request.data:
        abort(400)

    data = json.loads(request.data)

    nid = data.get("NetworkID", "")
    if not nid:
        abort(400)

    eid = data.get("EndpointID", "")
    if not eid:
        abort(400)

    try:
        neutron = neutron_login()
    except Exception as e:
        error = "%s" % (str(e))
        return jsonify({'Err': error})

    endpoint = get_endpointuuid_by_name(neutron, eid)
    if not endpoint:
        error = "Failed to get endpoint by name"
        return jsonify({'Err': error})

    try:
        ret = neutron.show_port(endpoint)
        mac_address = ret['port']['mac_address']
        ip_address = ret['port']['fixed_ips'][0]['ip_address']
    except Exception as e:
        error = "Failed to get endpoint information (%s)" % (str(e))
        return jsonify({'Err': error})

    veth_outside = eid[0:15]
    return jsonify({"Value": {"ip_address": ip_address,
                              "mac_address": mac_address,
                              "veth_outside": veth_outside
                              }})


# curl -i -H 'Content-Type: application/json' -X POST -d
# '{"NetworkID":"dummy-network","EndpointID":"dummy-endpoint"}'
# http://localhost:5000/NetworkDriver.DeleteEndpoint
@app.route('/NetworkDriver.DeleteEndpoint', methods=['POST'])
def delete_endpoint():
    if not request.data:
        abort(400)

    data = json.loads(request.data)

    nid = data.get("NetworkID", "")
    if not nid:
        abort(400)

    eid = data.get("EndpointID", "")
    if not eid:
        abort(400)

    try:
        neutron = neutron_login()
    except Exception as e:
        error = "%s" % (str(e))
        return jsonify({'Err': error})

    endpoint = get_endpointuuid_by_name(neutron, eid)
    if not endpoint:
        return jsonify({})

    if MODE == "underlay":
        reserved_vlan = ovs_vsctl("--if-exists get Open_vSwitch . "
                                  "external_ids:%s_vlan" % eid).strip('"')
        if reserved_vlan:
            unreserve_vlan(reserved_vlan)
            ovs_vsctl("remove Open_vSwitch . external_ids %s_vlan"
                      % eid)
        else:
            # This endpoint was not created on this host
            return jsonify({})

    try:
        neutron.delete_port(endpoint)
    except Exception as e:
        error = "Failed to delete endpoint. (%s)" % (str(e))
        return jsonify({'Err': error})

    return jsonify({})


# curl -i -H 'Content-Type: application/json' -X POST -d
# '{u'NetworkID': u'dummy-network', u'SandboxKey': u'sandbox-key', \
#   u'Options': {u'foo': u'fooValue'}, u'EndpointID': u'dummy-endpoint'}'
# http://localhost:5000/NetworkDriver.Join
@app.route('/NetworkDriver.Join', methods=['POST'])
def network_join():
    if not request.data:
        abort(400)

    data = json.loads(request.data)

    nid = data.get("NetworkID", "")
    if not nid:
        abort(400)

    eid = data.get("EndpointID", "")
    if not eid:
        abort(400)

    sboxkey = data.get("SandboxKey", "")
    if not sboxkey:
        abort(400)

    # sboxkey is of the form: /var/run/docker/netns/CONTAINER_ID
    vm_id = sboxkey.rsplit('/')[-1]

    try:
        neutron = neutron_login()
    except Exception as e:
        error = "%s" % (str(e))
        return jsonify({'Err': error})

    endpoint = get_endpointuuid_by_name(neutron, eid)
    if not endpoint:
        error = "Failed to get endpoint by name"
        return jsonify({'Err': error})

    try:
        ret = neutron.show_port(endpoint)
        mac_address = ret['port']['mac_address']
    except Exception as e:
        error = "Failed to get endpoint information (%s)" % (str(e))
        return jsonify({'Err': error})

    veth_outside = eid[0:15]
    veth_inside = eid[0:13] + "_c"
    command = "ip link add %s type veth peer name %s" \
              % (veth_inside, veth_outside)
    try:
        call_popen(shlex.split(command))
    except Exception as e:
        error = "Failed to create veth pair (%s)" % (str(e))
        return jsonify({'Err': error})

    command = "ip link set dev %s address %s" \
              % (veth_inside, mac_address)

    try:
        call_popen(shlex.split(command))
    except Exception as e:
        error = "Failed to set veth mac address (%s)" % (str(e))
        return jsonify({'Err': error})

    command = "ip link set %s up" % (veth_outside)

    try:
        call_popen(shlex.split(command))
    except Exception as e:
        error = "Failed to up the veth interface (%s)" % (str(e))
        return jsonify({'Err': error})

    try:
        if MODE == "underlay":
            reserved_vlan = ovs_vsctl("--if-exists get Open_vSwitch . "
                                      "external_ids:%s_vlan" % eid).strip('"')
            if not reserved_vlan:
                error = "No reserved vlan for this endpoint"
                return jsonify({'Err': error})
            ovs_vsctl("add-port %s %s tag=%s"
                      % (OVN_BRIDGE, veth_outside, reserved_vlan))
        else:
            ovs_vsctl("add-port %s %s" % (OVN_BRIDGE, veth_outside))
            ovs_vsctl("set interface %s external_ids:attached-mac=%s "
                      "external_ids:iface-id=%s "
                      "external_ids:vm-id=%s "
                      "external_ids:iface-status=%s "
                      % (veth_outside, mac_address, endpoint, vm_id, "active"))
    except Exception as e:
        error = "Failed to create a port (%s)" % (str(e))
        return jsonify({'Err': error})

    return jsonify({"InterfaceNames": [{
                                        "SrcName": veth_inside,
                                        "DstPrefix": "eth"
                                       }],
                    "Gateway": "",
                    "GatewayIPv6": "",
                    "HostsPath": "",
                    "ResolvConfPath": ""})


# curl -i -H 'Content-Type: application/json' -X POST -d
# '{"NetworkID":"dummy-network","EndpointID":"dummy-endpoint"}'
# http://localhost:5000/NetworkDriver.Leave
@app.route('/NetworkDriver.Leave', methods=['POST'])
def network_leave():
    if not request.data:
        abort(400)

    data = json.loads(request.data)

    nid = data.get("NetworkID", "")
    if not nid:
        abort(400)

    eid = data.get("EndpointID", "")
    if not eid:
        abort(400)

    veth_outside = eid[0:15]
    command = "ip link delete %s" % (veth_outside)
    try:
        call_popen(shlex.split(command))
    except Exception as e:
        error = "Failed to delete veth pair (%s)" % (str(e))
        return jsonify({'Err': error})

    try:
        ovs_vsctl("--if-exists del-port %s" % (veth_outside))
    except Exception as e:
        error = "Failed to delete port (%s)" % (str(e))
        return jsonify({'Err': error})

    return jsonify({})

if __name__ == '__main__':
    prepare()
    app.run(host='0.0.0.0')