src/emuvim/dcemulator/son_emu_simple_switch_13.py

   1 # Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
   2 #
   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
   6 #
   7 #    http://www.apache.org/licenses/LICENSE-2.0
   8 #
   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
  12 # implied.
  13 # See the License for the specific language governing permissions and
  14 # limitations under the License.
  15
  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
  23 from ryu.lib.packet import ether_types
  24 from ryu.topology.event import EventSwitchEnter, EventSwitchReconnected
  25
  26
  27 class SimpleSwitch13(app_manager.RyuApp):
  28     OFP_VERSIONS = [ofproto_v1_3.OFP_VERSION]
  29
  30     def __init__(self, *args, **kwargs):
  31         super(SimpleSwitch13, self).__init__(*args, **kwargs)
  32         self.mac_to_port = {}
  33
  34     @set_ev_cls(ofp_event.EventOFPSwitchFeatures, CONFIG_DISPATCHER)
  35     def switch_features_handler(self, ev):
  36         datapath = ev.msg.datapath
  37         ofproto = datapath.ofproto
  38         parser = datapath.ofproto_parser
  39
  40         # install table-miss flow entry
  41         #
  42         # We specify NO BUFFER to max_len of the output action due to
  43         # OVS bug. At this moment, if we specify a lesser number, e.g.,
  44         # 128, OVS will send Packet-In with invalid buffer_id and
  45         # truncated packet data. In that case, we cannot output packets
  46         # correctly.  The bug has been fixed in OVS v2.1.0.
  47         match = parser.OFPMatch()
  48         # actions = [parser.OFPActionOutput(ofproto.OFPP_CONTROLLER,
  49         #                                  ofproto.OFPCML_NO_BUFFER)]
  50         actions = [parser.OFPActionOutput(ofproto.OFPCML_NO_BUFFER)]
  51         self.add_flow(datapath, 0, match, actions)
  52
  53     def add_flow(self, datapath, priority, match,
  54                  actions, buffer_id=None, table_id=0):
  55         ofproto = datapath.ofproto
  56         parser = datapath.ofproto_parser
  57
  58         inst = [parser.OFPInstructionActions(ofproto.OFPIT_APPLY_ACTIONS,
  59                                              actions)]
  60         if buffer_id:
  61             mod = parser.OFPFlowMod(datapath=datapath, buffer_id=buffer_id,
  62                                     priority=priority, match=match,
  63                                     instructions=inst, table_id=table_id)
  64         else:
  65             mod = parser.OFPFlowMod(datapath=datapath, priority=priority,
  66                                     match=match, instructions=inst, table_id=table_id)
  67         datapath.send_msg(mod)
  68
  69         # new switch detected
  70
  71     @set_ev_cls([EventSwitchEnter, EventSwitchReconnected])
  72     def _ev_switch_enter_handler(self, ev):
  73         datapath = ev.switch.dp
  74         self.logger.info('registered OF switch id: %s' % datapath.id)
  75         ofproto = datapath.ofproto
  76         self.logger.info('OF version: {0}'.format(ofproto))
  77         # send NORMAL action for all undefined flows
  78         ofp_parser = datapath.ofproto_parser
  79         actions = [ofp_parser.OFPActionOutput(ofproto_v1_3.OFPP_NORMAL)]
  80         self.add_flow(datapath, 0, None, actions, table_id=0)
  81
  82     @set_ev_cls(ofp_event.EventOFPPacketIn, MAIN_DISPATCHER)
  83     def _packet_in_handler(self, ev):
  84         # If you hit this you might want to increase
  85         # the "miss_send_length" of your switch
  86         if ev.msg.msg_len < ev.msg.total_len:
  87             self.logger.debug("packet truncated: only %s of %s bytes",
  88                               ev.msg.msg_len, ev.msg.total_len)
  89         msg = ev.msg
  90         datapath = msg.datapath
  91         ofproto = datapath.ofproto
  92         parser = datapath.ofproto_parser
  93         in_port = msg.match['in_port']
  94
  95         pkt = packet.Packet(msg.data)
  96         eth = pkt.get_protocols(ethernet.ethernet)[0]
  97
  98         if eth.ethertype == ether_types.ETH_TYPE_LLDP:
  99             # ignore lldp packet
 100             return
 101         dst = eth.dst
 102         src = eth.src
 103
 104         dpid = datapath.id
 105         self.mac_to_port.setdefault(dpid, {})
 106
 107         self.logger.info("packet in %s %s %s %s", dpid, src, dst, in_port)
 108
 109         # learn a mac address to avoid FLOOD next time.
 110         self.mac_to_port[dpid][src] = in_port
 111
 112         if dst in self.mac_to_port[dpid]:
 113             out_port = self.mac_to_port[dpid][dst]
 114         else:
 115             out_port = ofproto.OFPP_FLOOD
 116
 117         actions = [parser.OFPActionOutput(out_port)]
 118
 119         # install a flow to avoid packet_in next time
 120         if out_port != ofproto.OFPP_FLOOD:
 121             match = parser.OFPMatch(in_port=in_port, eth_dst=dst)
 122             # verify if we have a valid buffer_id, if yes avoid to send both
 123             # flow_mod & packet_out
 124             if msg.buffer_id != ofproto.OFP_NO_BUFFER:
 125                 self.add_flow(datapath, 1, match, actions, msg.buffer_id)
 126                 return
 127             else:
 128                 self.add_flow(datapath, 1, match, actions)
 129         data = None
 130         if msg.buffer_id == ofproto.OFP_NO_BUFFER:
 131             data = msg.data
 132
 133         out = parser.OFPPacketOut(datapath=datapath, buffer_id=msg.buffer_id,
 134                                   in_port=in_port, actions=actions, data=data)
 135         datapath.send_msg(out)