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| -rw-r--r-- | ryu/app/example_switch_13.py | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/ryu/app/example_switch_13.py b/ryu/app/example_switch_13.py new file mode 100644 index 00000000..046e4ed0 --- /dev/null +++ b/ryu/app/example_switch_13.py @@ -0,0 +1,101 @@ +# Copyright (C) 2016 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. + +from ryu.base import app_manager +from ryu.controller import ofp_event +from ryu.controller.handler import CONFIG_DISPATCHER, MAIN_DISPATCHER +from ryu.controller.handler import set_ev_cls +from ryu.ofproto import ofproto_v1_3 +from ryu.lib.packet import packet +from ryu.lib.packet import ethernet + + +class ExampleSwitch13(app_manager.RyuApp): + OFP_VERSIONS = [ofproto_v1_3.OFP_VERSION] + + def __init__(self, *args, **kwargs): + super(ExampleSwitch13, self).__init__(*args, **kwargs) + # initialize mac address table. + self.mac_to_port = {} + + @set_ev_cls(ofp_event.EventOFPSwitchFeatures, CONFIG_DISPATCHER) + def switch_features_handler(self, ev): + datapath = ev.msg.datapath + ofproto = datapath.ofproto + parser = datapath.ofproto_parser + + # install the table-miss flow entry. + match = parser.OFPMatch() + actions = [parser.OFPActionOutput(ofproto.OFPP_CONTROLLER, + ofproto.OFPCML_NO_BUFFER)] + self.add_flow(datapath, 0, match, actions) + + def add_flow(self, datapath, priority, match, actions): + ofproto = datapath.ofproto + parser = datapath.ofproto_parser + + # construct flow_mod message and send it. + inst = [parser.OFPInstructionActions(ofproto.OFPIT_APPLY_ACTIONS, + actions)] + mod = parser.OFPFlowMod(datapath=datapath, priority=priority, + match=match, instructions=inst) + 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 + parser = datapath.ofproto_parser + + # get Datapath ID to identify OpenFlow switches. + dpid = datapath.id + self.mac_to_port.setdefault(dpid, {}) + + # analyse the received packets using the packet library. + pkt = packet.Packet(msg.data) + eth_pkt = pkt.get_protocol(ethernet.ethernet) + dst = eth_pkt.dst + src = eth_pkt.src + + # get the received port number from packet_in message. + in_port = msg.match['in_port'] + + self.logger.info("packet in %s %s %s %s", dpid, src, dst, in_port) + + # learn a mac address to avoid FLOOD next time. + self.mac_to_port[dpid][src] = in_port + + # if the destination mac address is already learned, + # decide which port to output the packet, otherwise FLOOD. + if dst in self.mac_to_port[dpid]: + out_port = self.mac_to_port[dpid][dst] + else: + out_port = ofproto.OFPP_FLOOD + + # construct action list. + actions = [parser.OFPActionOutput(out_port)] + + # install a flow to avoid packet_in next time. + if out_port != ofproto.OFPP_FLOOD: + match = parser.OFPMatch(in_port=in_port, eth_dst=dst) + self.add_flow(datapath, 1, match, actions) + + # construct packet_out message and send it. + out = parser.OFPPacketOut(datapath=datapath, + buffer_id=ofproto.OFP_NO_BUFFER, + in_port=in_port, actions=actions, + data=msg.data) + datapath.send_msg(out) |