os-ken/os_ken/app/simple_switch.py

111 lines
3.7 KiB
Python

# Copyright (C) 2011 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.
"""
An OpenFlow 1.0 L2 learning switch implementation.
"""
from os_ken.base import app_manager
from os_ken.controller import ofp_event
from os_ken.controller.handler import MAIN_DISPATCHER
from os_ken.controller.handler import set_ev_cls
from os_ken.ofproto import ofproto_v1_0
from os_ken.lib.mac import haddr_to_bin
from os_ken.lib.packet import packet
from os_ken.lib.packet import ethernet
from os_ken.lib.packet import ether_types
class SimpleSwitch(app_manager.RyuApp):
OFP_VERSIONS = [ofproto_v1_0.OFP_VERSION]
def __init__(self, *args, **kwargs):
super(SimpleSwitch, self).__init__(*args, **kwargs)
self.mac_to_port = {}
def add_flow(self, datapath, in_port, dst, src, actions):
ofproto = datapath.ofproto
match = datapath.ofproto_parser.OFPMatch(
in_port=in_port,
dl_dst=haddr_to_bin(dst), dl_src=haddr_to_bin(src))
mod = datapath.ofproto_parser.OFPFlowMod(
datapath=datapath, match=match, cookie=0,
command=ofproto.OFPFC_ADD, idle_timeout=0, hard_timeout=0,
priority=ofproto.OFP_DEFAULT_PRIORITY,
flags=ofproto.OFPFF_SEND_FLOW_REM, actions=actions)
datapath.send_msg(mod)
@set_ev_cls(ofp_event.EventOFPPacketIn, MAIN_DISPATCHER)
def _packet_in_handler(self, ev):
msg = ev.msg
datapath = msg.datapath
ofproto = datapath.ofproto
pkt = packet.Packet(msg.data)
eth = pkt.get_protocol(ethernet.ethernet)
if eth.ethertype == ether_types.ETH_TYPE_LLDP:
# ignore lldp packet
return
dst = eth.dst
src = eth.src
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, src, actions)
data = None
if msg.buffer_id == ofproto.OFP_NO_BUFFER:
data = msg.data
out = datapath.ofproto_parser.OFPPacketOut(
datapath=datapath, buffer_id=msg.buffer_id, in_port=msg.in_port,
actions=actions, data=data)
datapath.send_msg(out)
@set_ev_cls(ofp_event.EventOFPPortStatus, MAIN_DISPATCHER)
def _port_status_handler(self, ev):
msg = ev.msg
reason = msg.reason
port_no = msg.desc.port_no
ofproto = msg.datapath.ofproto
if reason == ofproto.OFPPR_ADD:
self.logger.info("port added %s", port_no)
elif reason == ofproto.OFPPR_DELETE:
self.logger.info("port deleted %s", port_no)
elif reason == ofproto.OFPPR_MODIFY:
self.logger.info("port modified %s", port_no)
else:
self.logger.info("Illeagal port state %s %s", port_no, reason)