1 # Copyright (C) 2016 Nippon Telegraph and Telephone Corporation.
3 # Licensed under the Apache License, Version 2.0 (the "License");
4 # you may not use this file except in compliance with the License.
5 # You may obtain a copy of the License at
7 # http://www.apache.org/licenses/LICENSE-2.0
9 # Unless required by applicable law or agreed to in writing, software
10 # distributed under the License is distributed on an "AS IS" BASIS,
11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
13 # See the License for the specific language governing permissions and
14 # limitations under the License.
16 from ryu.base import app_manager
17 from ryu.controller import ofp_event
18 from ryu.controller.handler import CONFIG_DISPATCHER, MAIN_DISPATCHER
19 from ryu.controller.handler import set_ev_cls
20 from ryu.ofproto import ofproto_v1_3
21 from ryu.lib.packet import packet
22 from ryu.lib.packet import ethernet
25 class ExampleSwitch13(app_manager.RyuApp):
26 OFP_VERSIONS = [ofproto_v1_3.OFP_VERSION]
28 def __init__(self, *args, **kwargs):
29 super(ExampleSwitch13, self).__init__(*args, **kwargs)
30 # initialize mac address table.
33 @set_ev_cls(ofp_event.EventOFPSwitchFeatures, CONFIG_DISPATCHER)
34 def switch_features_handler(self, ev):
35 datapath = ev.msg.datapath
36 ofproto = datapath.ofproto
37 parser = datapath.ofproto_parser
39 # install the table-miss flow entry.
40 match = parser.OFPMatch()
41 actions = [parser.OFPActionOutput(ofproto.OFPP_CONTROLLER,
42 ofproto.OFPCML_NO_BUFFER)]
43 self.add_flow(datapath, 0, match, actions)
45 def add_flow(self, datapath, priority, match, actions):
46 ofproto = datapath.ofproto
47 parser = datapath.ofproto_parser
49 # construct flow_mod message and send it.
50 inst = [parser.OFPInstructionActions(ofproto.OFPIT_APPLY_ACTIONS,
52 mod = parser.OFPFlowMod(datapath=datapath, priority=priority,
53 match=match, instructions=inst)
54 datapath.send_msg(mod)
56 @set_ev_cls(ofp_event.EventOFPPacketIn, MAIN_DISPATCHER)
57 def _packet_in_handler(self, ev):
59 datapath = msg.datapath
60 ofproto = datapath.ofproto
61 parser = datapath.ofproto_parser
63 # get Datapath ID to identify OpenFlow switches.
65 self.mac_to_port.setdefault(dpid, {})
67 # analyse the received packets using the packet library.
68 pkt = packet.Packet(msg.data)
69 eth_pkt = pkt.get_protocol(ethernet.ethernet)
73 # get the received port number from packet_in message.
74 in_port = msg.match['in_port']
76 self.logger.info("packet in %s %s %s %s", dpid, src, dst, in_port)
78 # learn a mac address to avoid FLOOD next time.
79 self.mac_to_port[dpid][src] = in_port
81 # if the destination mac address is already learned,
82 # decide which port to output the packet, otherwise FLOOD.
83 if dst in self.mac_to_port[dpid]:
84 out_port = self.mac_to_port[dpid][dst]
86 out_port = ofproto.OFPP_FLOOD
88 # construct action list.
89 actions = [parser.OFPActionOutput(out_port)]
91 # install a flow to avoid packet_in next time.
92 if out_port != ofproto.OFPP_FLOOD:
93 match = parser.OFPMatch(in_port=in_port, eth_dst=dst)
94 self.add_flow(datapath, 1, match, actions)
96 # construct packet_out message and send it.
97 out = parser.OFPPacketOut(datapath=datapath,
98 buffer_id=ofproto.OFP_NO_BUFFER,
99 in_port=in_port, actions=actions,
101 datapath.send_msg(out)