os-ken/ryu/app/simple_switch_igmp.py
Yuichi Ito ffc1f82554 add IGMP snooping application
this application provides the simple example of IGMP snooping.

the module "igmplib" mainly offers 2 functions:
- listening on in the IGMP conversation between multicast routers and hosts
- emulating of the querier function of multicast servers
the former operates a switch as a snooping switch and controls transmission of an unnecessary multicasting packet.
the latter realizes the IGMP conversation in the environment without multicast routers.

the module "simple_switch_igmp" is a variation of "simple_switch".
the switch receives the "EventPacketIn" event instead of the "EventOFPPacketIn" event from the module "igmplib" in order to except IGMP.

Signed-off-by: Yuichi Ito <ito.yuichi0@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
2014-01-06 20:28:01 +09:00

105 lines
3.8 KiB
Python

# Copyright (C) 2013 Nippon Telegraph and Telephone 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.
import struct
from ryu.base import app_manager
from ryu.controller.handler import MAIN_DISPATCHER
from ryu.controller.handler import set_ev_cls
from ryu.ofproto import ofproto_v1_0
from ryu.lib import addrconv
from ryu.lib import igmplib
from ryu.lib.dpid import str_to_dpid
class SimpleSwitchIgmp(app_manager.RyuApp):
OFP_VERSIONS = [ofproto_v1_0.OFP_VERSION]
_CONTEXTS = {'igmplib': igmplib.IgmpLib}
def __init__(self, *args, **kwargs):
super(SimpleSwitchIgmp, self).__init__(*args, **kwargs)
self.mac_to_port = {}
self._snoop = kwargs['igmplib']
# if you want a switch to operate as a querier,
# set up as follows:
self._snoop.set_querier_mode(
dpid=str_to_dpid('0000000000000001'), server_port=2)
# dpid the datapath id that will operate as a querier.
# server_port a port number which connect to the multicast
# server.
#
# NOTE: you can set up only the one querier.
# when you called this method several times,
# only the last one becomes effective.
def add_flow(self, datapath, in_port, dst, actions):
ofproto = datapath.ofproto
parser = datapath.ofproto_parser
match = parser.OFPMatch(in_port=in_port,
dl_dst=addrconv.mac.text_to_bin(dst))
mod = parser.OFPFlowMod(
datapath=datapath, match=match, cookie=0,
command=ofproto.OFPFC_ADD, actions=actions)
datapath.send_msg(mod)
@set_ev_cls(igmplib.EventPacketIn, MAIN_DISPATCHER)
def _packet_in_handler(self, ev):
msg = ev.msg
datapath = msg.datapath
ofproto = datapath.ofproto
(dst_, src_, _eth_type) = struct.unpack_from(
'!6s6sH', buffer(msg.data), 0)
src = addrconv.mac.bin_to_text(src_)
dst = addrconv.mac.bin_to_text(dst_)
dpid = datapath.id
self.mac_to_port.setdefault(dpid, {})
self.logger.info("packet in %s %s %s %s",
dpid, src, dst, msg.in_port)
# learn a mac address to avoid FLOOD next time.
self.mac_to_port[dpid][src] = msg.in_port
if dst in self.mac_to_port[dpid]:
out_port = self.mac_to_port[dpid][dst]
else:
out_port = ofproto.OFPP_FLOOD
actions = [datapath.ofproto_parser.OFPActionOutput(out_port)]
# install a flow to avoid packet_in next time
if out_port != ofproto.OFPP_FLOOD:
self.add_flow(datapath, msg.in_port, dst, actions)
out = datapath.ofproto_parser.OFPPacketOut(
datapath=datapath, buffer_id=msg.buffer_id, in_port=msg.in_port,
actions=actions)
datapath.send_msg(out)
@set_ev_cls(igmplib.EventMulticastGroupStateChanged,
MAIN_DISPATCHER)
def _status_changed(self, ev):
msg = {
igmplib.MG_GROUP_ADDED: 'Multicast Group Added',
igmplib.MG_MEMBER_CHANGED: 'Multicast Group Member Changed',
igmplib.MG_GROUP_REMOVED: 'Multicast Group Removed',
}
self.logger.info("%s: [%s] querier:[%s] hosts:%s",
msg.get(ev.reason), ev.address, ev.src,
ev.dsts)