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