102 lines
3.8 KiB
Python
102 lines
3.8 KiB
Python
# Copyright (C) 2016 Nippon Telegraph and Telephone Corporation.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
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# implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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from os_ken.base import app_manager
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from os_ken.controller import ofp_event
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from os_ken.controller.handler import CONFIG_DISPATCHER, MAIN_DISPATCHER
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from os_ken.controller.handler import set_ev_cls
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from os_ken.ofproto import ofproto_v1_3
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from os_ken.lib.packet import packet
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from os_ken.lib.packet import ethernet
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class ExampleSwitch13(app_manager.RyuApp):
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OFP_VERSIONS = [ofproto_v1_3.OFP_VERSION]
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def __init__(self, *args, **kwargs):
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super(ExampleSwitch13, self).__init__(*args, **kwargs)
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# initialize mac address table.
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self.mac_to_port = {}
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@set_ev_cls(ofp_event.EventOFPSwitchFeatures, CONFIG_DISPATCHER)
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def switch_features_handler(self, ev):
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datapath = ev.msg.datapath
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ofproto = datapath.ofproto
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parser = datapath.ofproto_parser
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# install the table-miss flow entry.
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match = parser.OFPMatch()
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actions = [parser.OFPActionOutput(ofproto.OFPP_CONTROLLER,
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ofproto.OFPCML_NO_BUFFER)]
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self.add_flow(datapath, 0, match, actions)
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def add_flow(self, datapath, priority, match, actions):
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ofproto = datapath.ofproto
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parser = datapath.ofproto_parser
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# construct flow_mod message and send it.
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inst = [parser.OFPInstructionActions(ofproto.OFPIT_APPLY_ACTIONS,
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actions)]
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mod = parser.OFPFlowMod(datapath=datapath, priority=priority,
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match=match, instructions=inst)
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datapath.send_msg(mod)
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@set_ev_cls(ofp_event.EventOFPPacketIn, MAIN_DISPATCHER)
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def _packet_in_handler(self, ev):
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msg = ev.msg
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datapath = msg.datapath
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ofproto = datapath.ofproto
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parser = datapath.ofproto_parser
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# get Datapath ID to identify OpenFlow switches.
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dpid = datapath.id
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self.mac_to_port.setdefault(dpid, {})
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# analyse the received packets using the packet library.
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pkt = packet.Packet(msg.data)
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eth_pkt = pkt.get_protocol(ethernet.ethernet)
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dst = eth_pkt.dst
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src = eth_pkt.src
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# get the received port number from packet_in message.
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in_port = msg.match['in_port']
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self.logger.info("packet in %s %s %s %s", dpid, src, dst, in_port)
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# learn a mac address to avoid FLOOD next time.
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self.mac_to_port[dpid][src] = in_port
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# if the destination mac address is already learned,
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# decide which port to output the packet, otherwise FLOOD.
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if dst in self.mac_to_port[dpid]:
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out_port = self.mac_to_port[dpid][dst]
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else:
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out_port = ofproto.OFPP_FLOOD
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# construct action list.
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actions = [parser.OFPActionOutput(out_port)]
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# install a flow to avoid packet_in next time.
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if out_port != ofproto.OFPP_FLOOD:
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match = parser.OFPMatch(in_port=in_port, eth_dst=dst)
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self.add_flow(datapath, 1, match, actions)
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# construct packet_out message and send it.
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out = parser.OFPPacketOut(datapath=datapath,
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buffer_id=ofproto.OFP_NO_BUFFER,
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in_port=in_port, actions=actions,
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data=msg.data)
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datapath.send_msg(out)
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