ryu/ryu/lib/stplib.py

   1 # Copyright (C) 2013 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
  17 import datetime
  18 import logging
  19
  20 from ryu.base import app_manager
  21 from ryu.controller import event
  22 from ryu.controller import handler
  23 from ryu.controller import ofp_event
  24 from ryu.controller.handler import set_ev_cls
  25 from ryu.exception import RyuException
  26 from ryu.exception import OFPUnknownVersion
  27 from ryu.lib import hub
  28 from ryu.lib import mac
  29 from ryu.lib.dpid import dpid_to_str
  30 from ryu.lib.packet import bpdu
  31 from ryu.lib.packet import ethernet
  32 from ryu.lib.packet import llc
  33 from ryu.lib.packet import packet
  34 from ryu.ofproto import ofproto_v1_0
  35 from ryu.ofproto import ofproto_v1_2
  36 from ryu.ofproto import ofproto_v1_3
  37
  38
  39 MAX_PORT_NO = 0xfff
  40
  41 # for OpenFlow 1.2/1.3
  42 BPDU_PKT_IN_PRIORITY = 0xffff
  43 NO_PKT_IN_PRIORITY = 0xfffe
  44
  45
  46 # Result of compared config BPDU priority.
  47 SUPERIOR = -1
  48 REPEATED = 0
  49 INFERIOR = 1
  50
  51 # Port role
  52 DESIGNATED_PORT = 0  # The port which sends BPDU.
  53 ROOT_PORT = 1  # The port which receives BPDU from a root bridge.
  54 NON_DESIGNATED_PORT = 2  # The port which blocked.
  55
  56 """ How to decide the port roles.
  57
  58      Root bridge:
  59        a bridge has smallest bridge ID is chosen as a root.
  60        it sends original config BPDU.
  61      Non Root bridge:
  62        forwards config BPDU received from the root bridge.
  63
  64                    +-----------------------+
  65                    |      Root bridge      |
  66                    +-----------------------+
  67                      (D)               (D)
  68                       |                 |
  69                       |                 |
  70                      (R)               (R)
  71         +-----------------+          +-----------------+
  72         | Non Root bridge |(D)---(ND)| Non Root bridge |
  73         +-----------------+          +-----------------+
  74
  75      ROOT_PORT(R):
  76        the nearest port to a root bridge of the bridge.
  77        it is determined by the cost of the path, etc.
  78      DESIGNATED_PORT(D):
  79        the port of the side near the root bridge of each link.
  80        it is determined by the cost of the path, etc.
  81      NON_DESIGNATED_PORT(ND):
  82        the port other than a ROOT_PORT and DESIGNATED_PORT.
  83 """
  84
  85
  86 # Port state
  87 #  DISABLE: Administratively down or link down by an obstacle.
  88 #  BLOCK  : Not part of spanning tree.
  89 #  LISTEN : Not learning or relaying frames.
  90 #  LEARN  : Learning but not relaying frames.
  91 #  FORWARD: Learning and relaying frames.
  92 PORT_STATE_DISABLE = 0
  93 PORT_STATE_BLOCK = 1
  94 PORT_STATE_LISTEN = 2
  95 PORT_STATE_LEARN = 3
  96 PORT_STATE_FORWARD = 4
  97
  98 # for OpenFlow 1.0
  99 PORT_CONFIG_V1_0 = {PORT_STATE_DISABLE: (ofproto_v1_0.OFPPC_NO_RECV_STP
 100                                          | ofproto_v1_0.OFPPC_NO_RECV
 101                                          | ofproto_v1_0.OFPPC_NO_FLOOD
 102                                          | ofproto_v1_0.OFPPC_NO_FWD),
 103                     PORT_STATE_BLOCK: (ofproto_v1_0.OFPPC_NO_RECV
 104                                        | ofproto_v1_0.OFPPC_NO_FLOOD
 105                                        | ofproto_v1_0.OFPPC_NO_FWD),
 106                     PORT_STATE_LISTEN: (ofproto_v1_0.OFPPC_NO_RECV
 107                                         | ofproto_v1_0.OFPPC_NO_FLOOD),
 108                     PORT_STATE_LEARN: ofproto_v1_0.OFPPC_NO_FLOOD,
 109                     PORT_STATE_FORWARD: 0}
 110
 111 # for OpenFlow 1.2
 112 PORT_CONFIG_V1_2 = {PORT_STATE_DISABLE: (ofproto_v1_2.OFPPC_NO_RECV
 113                                          | ofproto_v1_2.OFPPC_NO_FWD),
 114                     PORT_STATE_BLOCK: (ofproto_v1_2.OFPPC_NO_FWD
 115                                        | ofproto_v1_2.OFPPC_NO_PACKET_IN),
 116                     PORT_STATE_LISTEN: ofproto_v1_2.OFPPC_NO_PACKET_IN,
 117                     PORT_STATE_LEARN: ofproto_v1_2.OFPPC_NO_PACKET_IN,
 118                     PORT_STATE_FORWARD: 0}
 119
 120 # for OpenFlow 1.3
 121 PORT_CONFIG_V1_3 = {PORT_STATE_DISABLE: (ofproto_v1_3.OFPPC_NO_RECV
 122                                          | ofproto_v1_3.OFPPC_NO_FWD),
 123                     PORT_STATE_BLOCK: (ofproto_v1_3.OFPPC_NO_FWD
 124                                        | ofproto_v1_3.OFPPC_NO_PACKET_IN),
 125                     PORT_STATE_LISTEN: ofproto_v1_3.OFPPC_NO_PACKET_IN,
 126                     PORT_STATE_LEARN: ofproto_v1_3.OFPPC_NO_PACKET_IN,
 127                     PORT_STATE_FORWARD: 0}
 128
 129 """ Port state machine
 130
 131     +------------------------<--------------------------+
 132     |                                                   |*2
 133     +--> [BLOCK] -----+--> [LISTEN] ----> [LEARN] ------+----> [FORWARD]
 134                   *3  |        |    15sec    |    15sec   *1       |
 135                       |        |*3           |*3                   |*3
 136                       +----<---+------<------+----------<----------+
 137
 138           *1 if port role == DESIGNATED_PORT or ROOT_PORT
 139           *2 if port role == NON_DESIGNATED_PORT
 140           *3 re-calculation of Spanning tree occurred.
 141
 142       When bridge has started, each port state is set to [LISTEN]
 143        except port configuration is disable.
 144       If port configuration is disable or link down occurred,
 145        the port state is set to [DISABLE]
 146 """
 147
 148
 149 # Throw this event when network topology is changed.
 150 # Flush filtering database, when you receive this event.
 151 class EventTopologyChange(event.EventBase):
 152     def __init__(self, dp):
 153         super(EventTopologyChange, self).__init__()
 154         self.dp = dp
 155
 156
 157 # Throw this event when port status is changed.
 158 class EventPortStateChange(event.EventBase):
 159     def __init__(self, dp, port):
 160         super(EventPortStateChange, self).__init__()
 161         self.dp = dp
 162         self.port_no = port.ofport.port_no
 163         self.port_state = port.state
 164
 165
 166 # Event for receive packet in message except BPDU packet.
 167 class EventPacketIn(event.EventBase):
 168     def __init__(self, msg):
 169         super(EventPacketIn, self).__init__()
 170         self.msg = msg
 171
 172
 173 # For Python3 compatibility
 174 # Note: The following is the official workaround for cmp() in Python2.
 175 # https://docs.python.org/3.0/whatsnew/3.0.html#ordering-comparisons
 176 def cmp(a, b):
 177     return (a > b) - (a < b)
 178
 179
 180 class Stp(app_manager.RyuApp):
 181     """ STP(spanning tree) library. """
 182
 183     OFP_VERSIONS = [ofproto_v1_0.OFP_VERSION,
 184                     ofproto_v1_2.OFP_VERSION,
 185                     ofproto_v1_3.OFP_VERSION]
 186
 187     def __init__(self):
 188         super(Stp, self).__init__()
 189         self.name = 'stplib'
 190         self._set_logger()
 191         self.config = {}
 192         self.bridge_list = {}
 193
 194     def close(self):
 195         for dpid in self.bridge_list:
 196             self._unregister_bridge(dpid)
 197
 198     def _set_logger(self):
 199         self.logger.propagate = False
 200         hdlr = logging.StreamHandler()
 201         fmt_str = '[STP][%(levelname)s] dpid=%(dpid)s: %(message)s'
 202         hdlr.setFormatter(logging.Formatter(fmt_str))
 203         self.logger.addHandler(hdlr)
 204
 205     def set_config(self, config):
 206         """ Use this API if you want to set up configuration
 207              of each bridge and ports.
 208             Set configuration with 'config' parameter as follows.
 209
 210              config = {<dpid>: {'bridge': {'priority': <value>,
 211                                            'sys_ext_id': <value>,
 212                                            'max_age': <value>,
 213                                            'hello_time': <value>,
 214                                            'fwd_delay': <value>}
 215                                 'ports': {<port_no>: {'priority': <value>,
 216                                                       'path_cost': <value>,
 217                                                       'enable': <True/False>},
 218                                           <port_no>: {...},,,}}
 219                        <dpid>: {...},
 220                        <dpid>: {...},,,}
 221
 222              NOTE: You may omit each field.
 223                     If omitted, a default value is set up.
 224                    It becomes effective when a bridge starts.
 225
 226              Default values:
 227              ------------------------------------------------------
 228              | bridge | priority   | bpdu.DEFAULT_BRIDGE_PRIORITY |
 229              |        | sys_ext_id | 0                            |
 230              |        | max_age    | bpdu.DEFAULT_MAX_AGE         |
 231              |        | hello_time | bpdu.DEFAULT_HELLO_TIME      |
 232              |        | fwd_delay  | bpdu.DEFAULT_FORWARD_DELAY   |
 233              |--------|------------|------------------------------|
 234              | port   | priority   | bpdu.DEFAULT_PORT_PRIORITY   |
 235              |        | path_cost  | (Set up automatically        |
 236              |        |            |   according to link speed.)  |
 237              |        | enable     | True                         |
 238              ------------------------------------------------------
 239         """
 240         assert isinstance(config, dict)
 241         self.config = config
 242
 243     @set_ev_cls(ofp_event.EventOFPStateChange,
 244                 [handler.MAIN_DISPATCHER, handler.DEAD_DISPATCHER])
 245     def dispacher_change(self, ev):
 246         assert ev.datapath is not None
 247         if ev.state == handler.MAIN_DISPATCHER:
 248             self._register_bridge(ev.datapath)
 249         elif ev.state == handler.DEAD_DISPATCHER:
 250             self._unregister_bridge(ev.datapath.id)
 251
 252     def _register_bridge(self, dp):
 253         self._unregister_bridge(dp.id)
 254
 255         dpid_str = {'dpid': dpid_to_str(dp.id)}
 256         self.logger.info('Join as stp bridge.', extra=dpid_str)
 257         try:
 258             bridge = Bridge(dp, self.logger,
 259                             self.config.get(dp.id, {}),
 260                             self.send_event_to_observers)
 261         except OFPUnknownVersion as message:
 262             self.logger.error(str(message), extra=dpid_str)
 263             return
 264
 265         self.bridge_list[dp.id] = bridge
 266
 267     def _unregister_bridge(self, dp_id):
 268         if dp_id in self.bridge_list:
 269             self.bridge_list[dp_id].delete()
 270             del self.bridge_list[dp_id]
 271             self.logger.info('Leave stp bridge.',
 272                              extra={'dpid': dpid_to_str(dp_id)})
 273
 274     @set_ev_cls(ofp_event.EventOFPPacketIn, handler.MAIN_DISPATCHER)
 275     def packet_in_handler(self, ev):
 276         if ev.msg.datapath.id in self.bridge_list:
 277             bridge = self.bridge_list[ev.msg.datapath.id]
 278             bridge.packet_in_handler(ev.msg)
 279
 280     @set_ev_cls(ofp_event.EventOFPPortStatus, handler.MAIN_DISPATCHER)
 281     def port_status_handler(self, ev):
 282         dp = ev.msg.datapath
 283         dpid_str = {'dpid': dpid_to_str(dp.id)}
 284         port = ev.msg.desc
 285         reason = ev.msg.reason
 286         link_down_flg = port.state & 0b1
 287
 288         if dp.id in self.bridge_list:
 289             bridge = self.bridge_list[dp.id]
 290
 291             if reason is dp.ofproto.OFPPR_ADD:
 292                 self.logger.info('[port=%d] Port add.',
 293                                  port.port_no, extra=dpid_str)
 294                 bridge.port_add(port)
 295             elif reason is dp.ofproto.OFPPR_DELETE:
 296                 self.logger.info('[port=%d] Port delete.',
 297                                  port.port_no, extra=dpid_str)
 298                 bridge.port_delete(port)
 299             else:
 300                 assert reason is dp.ofproto.OFPPR_MODIFY
 301                 if bridge.ports_state[port.port_no] == port.state:
 302                     # Do nothing
 303                     self.logger.debug('[port=%d] Link status not changed.',
 304                                       port.port_no, extra=dpid_str)
 305                     return
 306                 if link_down_flg:
 307                     self.logger.info('[port=%d] Link down.',
 308                                      port.port_no, extra=dpid_str)
 309                     bridge.link_down(port)
 310                 else:
 311                     self.logger.info('[port=%d] Link up.',
 312                                      port.port_no, extra=dpid_str)
 313                     bridge.link_up(port)
 314
 315     @staticmethod
 316     def compare_root_path(path_cost1, path_cost2, bridge_id1, bridge_id2,
 317                           port_id1, port_id2):
 318         """ Decide the port of the side near a root bridge.
 319             It is compared by the following priorities.
 320              1. root path cost
 321              2. designated bridge ID value
 322              3. designated port ID value """
 323         result = Stp._cmp_value(path_cost1, path_cost2)
 324         if not result:
 325             result = Stp._cmp_value(bridge_id1, bridge_id2)
 326             if not result:
 327                 result = Stp._cmp_value(port_id1, port_id2)
 328         return result
 329
 330     @staticmethod
 331     def compare_bpdu_info(my_priority, my_times, rcv_priority, rcv_times):
 332         """ Check received BPDU is superior to currently held BPDU
 333              by the following comparison.
 334              - root bridge ID value
 335              - root path cost
 336              - designated bridge ID value
 337              - designated port ID value
 338              - times """
 339         if my_priority is None:
 340             result = SUPERIOR
 341         else:
 342             result = Stp._cmp_value(rcv_priority.root_id.value,
 343                                     my_priority.root_id.value)
 344             if not result:
 345                 result = Stp.compare_root_path(
 346                     rcv_priority.root_path_cost,
 347                     my_priority.root_path_cost,
 348                     rcv_priority.designated_bridge_id.value,
 349                     my_priority.designated_bridge_id.value,
 350                     rcv_priority.designated_port_id.value,
 351                     my_priority.designated_port_id.value)
 352                 if not result:
 353                     result1 = Stp._cmp_value(
 354                         rcv_priority.designated_bridge_id.value,
 355                         mac.haddr_to_int(
 356                             my_priority.designated_bridge_id.mac_addr))
 357                     result2 = Stp._cmp_value(
 358                         rcv_priority.designated_port_id.value,
 359                         my_priority.designated_port_id.port_no)
 360                     if not result1 and not result2:
 361                         result = SUPERIOR
 362                     else:
 363                         result = Stp._cmp_obj(rcv_times, my_times)
 364         return result
 365
 366     @staticmethod
 367     def _cmp_value(value1, value2):
 368         result = cmp(value1, value2)
 369         if result < 0:
 370             return SUPERIOR
 371         elif result == 0:
 372             return REPEATED
 373         else:
 374             return INFERIOR
 375
 376     @staticmethod
 377     def _cmp_obj(obj1, obj2):
 378         for key in obj1.__dict__.keys():
 379             if (not hasattr(obj2, key)
 380                     or getattr(obj1, key) != getattr(obj2, key)):
 381                 return SUPERIOR
 382         return REPEATED
 383
 384
 385 class Bridge(object):
 386     _DEFAULT_VALUE = {'priority': bpdu.DEFAULT_BRIDGE_PRIORITY,
 387                       'sys_ext_id': 0,
 388                       'max_age': bpdu.DEFAULT_MAX_AGE,
 389                       'hello_time': bpdu.DEFAULT_HELLO_TIME,
 390                       'fwd_delay': bpdu.DEFAULT_FORWARD_DELAY}
 391
 392     def __init__(self, dp, logger, config, send_ev_func):
 393         super(Bridge, self).__init__()
 394         self.dp = dp
 395         self.logger = logger
 396         self.dpid_str = {'dpid': dpid_to_str(dp.id)}
 397         self.send_event = send_ev_func
 398
 399         # Bridge data
 400         bridge_conf = config.get('bridge', {})
 401         values = self._DEFAULT_VALUE
 402         for key, value in bridge_conf.items():
 403             values[key] = value
 404         system_id = list(dp.ports.values())[0].hw_addr
 405
 406         self.bridge_id = BridgeId(values['priority'],
 407                                   values['sys_ext_id'],
 408                                   system_id)
 409         self.bridge_times = Times(0,  # message_age
 410                                   values['max_age'],
 411                                   values['hello_time'],
 412                                   values['fwd_delay'])
 413         # Root bridge data
 414         self.root_priority = Priority(self.bridge_id, 0, None, None)
 415         self.root_times = self.bridge_times
 416         # Ports
 417         self.ports = {}
 418         self.ports_state = {}
 419         self.ports_conf = config.get('ports', {})
 420         for ofport in dp.ports.values():
 421             self.port_add(ofport)
 422
 423         # Install BPDU PacketIn flow. (OpenFlow 1.2/1.3)
 424         if dp.ofproto == ofproto_v1_2 or dp.ofproto == ofproto_v1_3:
 425             ofctl = OfCtl_v1_2later(self.dp)
 426             ofctl.add_bpdu_pkt_in_flow()
 427
 428     @property
 429     def is_root_bridge(self):
 430         return bool(self.bridge_id.value == self.root_priority.root_id.value)
 431
 432     def delete(self):
 433         for port in self.ports.values():
 434             port.delete()
 435
 436     def port_add(self, ofport):
 437         if ofport.port_no <= MAX_PORT_NO:
 438             port_conf = self.ports_conf.get(ofport.port_no, {})
 439             self.ports[ofport.port_no] = Port(self.dp, self.logger,
 440                                               port_conf, self.send_event,
 441                                               self.recalculate_spanning_tree,
 442                                               self.topology_change_notify,
 443                                               self.bridge_id,
 444                                               self.bridge_times,
 445                                               ofport)
 446             self.ports_state[ofport.port_no] = ofport.state
 447
 448     def port_delete(self, ofp_port):
 449         self.link_down(ofp_port)
 450         self.ports[ofp_port.port_no].delete()
 451         del self.ports[ofp_port.port_no]
 452         del self.ports_state[ofp_port.port_no]
 453
 454     def link_up(self, ofp_port):
 455         port = self.ports[ofp_port.port_no]
 456         port.up(DESIGNATED_PORT, self.root_priority, self.root_times)
 457         self.ports_state[ofp_port.port_no] = ofp_port.state
 458
 459     def link_down(self, ofp_port):
 460         """ DESIGNATED_PORT/NON_DESIGNATED_PORT: change status to DISABLE.
 461             ROOT_PORT: change status to DISABLE and recalculate STP. """
 462         port = self.ports[ofp_port.port_no]
 463         init_stp_flg = bool(port.role is ROOT_PORT)
 464
 465         port.down(PORT_STATE_DISABLE, msg_init=True)
 466         self.ports_state[ofp_port.port_no] = ofp_port.state
 467         if init_stp_flg:
 468             self.recalculate_spanning_tree()
 469
 470     def packet_in_handler(self, msg):
 471         dp = msg.datapath
 472         if dp.ofproto == ofproto_v1_0:
 473             in_port_no = msg.in_port
 474         else:
 475             assert dp.ofproto == ofproto_v1_2 or dp.ofproto == ofproto_v1_3
 476             in_port_no = None
 477             for match_field in msg.match.fields:
 478                 if match_field.header == dp.ofproto.OXM_OF_IN_PORT:
 479                     in_port_no = match_field.value
 480                     break
 481         if in_port_no not in self.ports:
 482             return
 483
 484         in_port = self.ports[in_port_no]
 485         if in_port.state == PORT_STATE_DISABLE:
 486             return
 487
 488         pkt = packet.Packet(msg.data)
 489         if bpdu.ConfigurationBPDUs in pkt:
 490             # Received Configuration BPDU.
 491             # - If received superior BPDU:
 492             #    Re-calculates spanning tree.
 493             # - If received Topology Change BPDU:
 494             #    Throws EventTopologyChange.
 495             #    Forwards Topology Change BPDU.
 496             (bpdu_pkt, ) = pkt.get_protocols(bpdu.ConfigurationBPDUs)
 497             if bpdu_pkt.message_age > bpdu_pkt.max_age:
 498                 log_msg = 'Drop BPDU packet which message_age exceeded.'
 499                 self.logger.debug(log_msg, extra=self.dpid_str)
 500                 return
 501
 502             rcv_info, rcv_tc = in_port.rcv_config_bpdu(bpdu_pkt)
 503
 504             if rcv_info is SUPERIOR:
 505                 self.logger.info('[port=%d] Receive superior BPDU.',
 506                                  in_port_no, extra=self.dpid_str)
 507                 self.recalculate_spanning_tree(init=False)
 508
 509             elif rcv_tc:
 510                 self.send_event(EventTopologyChange(self.dp))
 511
 512             if in_port.role is ROOT_PORT:
 513                 self._forward_tc_bpdu(rcv_tc)
 514
 515         elif bpdu.TopologyChangeNotificationBPDUs in pkt:
 516             # Received Topology Change Notification BPDU.
 517             # Send Topology Change Ack BPDU and throws EventTopologyChange.
 518             # - Root bridge:
 519             #    Sends Topology Change BPDU from all port.
 520             # - Non root bridge:
 521             #    Sends Topology Change Notification BPDU to root bridge.
 522             in_port.transmit_ack_bpdu()
 523             self.topology_change_notify(None)
 524
 525         elif bpdu.RstBPDUs in pkt:
 526             # Received Rst BPDU.
 527             # TODO: RSTP
 528             pass
 529
 530         else:
 531             # Received non BPDU packet.
 532             # Throws EventPacketIn.
 533             self.send_event(EventPacketIn(msg))
 534
 535     def recalculate_spanning_tree(self, init=True):
 536         """ Re-calculation of spanning tree. """
 537         # All port down.
 538         for port in self.ports.values():
 539             if port.state is not PORT_STATE_DISABLE:
 540                 port.down(PORT_STATE_BLOCK, msg_init=init)
 541
 542         # Send topology change event.
 543         if init:
 544             self.send_event(EventTopologyChange(self.dp))
 545
 546         # Update tree roles.
 547         port_roles = {}
 548         self.root_priority = Priority(self.bridge_id, 0, None, None)
 549         self.root_times = self.bridge_times
 550
 551         if init:
 552             self.logger.info('Root bridge.', extra=self.dpid_str)
 553             for port_no in self.ports:
 554                 port_roles[port_no] = DESIGNATED_PORT
 555         else:
 556             (port_roles,
 557              self.root_priority,
 558              self.root_times) = self._spanning_tree_algorithm()
 559
 560         # All port up.
 561         for port_no, role in port_roles.items():
 562             if self.ports[port_no].state is not PORT_STATE_DISABLE:
 563                 self.ports[port_no].up(role, self.root_priority,
 564                                        self.root_times)
 565
 566     def _spanning_tree_algorithm(self):
 567         """ Update tree roles.
 568              - Root bridge:
 569                 all port is DESIGNATED_PORT.
 570              - Non root bridge:
 571                 select one ROOT_PORT and some DESIGNATED_PORT,
 572                 and the other port is set to NON_DESIGNATED_PORT."""
 573         port_roles = {}
 574
 575         root_port = self._select_root_port()
 576
 577         if root_port is None:
 578             # My bridge is a root bridge.
 579             self.logger.info('Root bridge.', extra=self.dpid_str)
 580             root_priority = self.root_priority
 581             root_times = self.root_times
 582
 583             for port_no in self.ports:
 584                 if self.ports[port_no].state is not PORT_STATE_DISABLE:
 585                     port_roles[port_no] = DESIGNATED_PORT
 586         else:
 587             # Other bridge is a root bridge.
 588             self.logger.info('Non root bridge.', extra=self.dpid_str)
 589             root_priority = root_port.designated_priority
 590             root_times = root_port.designated_times
 591
 592             port_roles[root_port.ofport.port_no] = ROOT_PORT
 593
 594             d_ports = self._select_designated_port(root_port)
 595             for port_no in d_ports:
 596                 port_roles[port_no] = DESIGNATED_PORT
 597
 598             for port in self.ports.values():
 599                 if port.state is not PORT_STATE_DISABLE:
 600                     port_roles.setdefault(port.ofport.port_no,
 601                                           NON_DESIGNATED_PORT)
 602
 603         return port_roles, root_priority, root_times
 604
 605     def _select_root_port(self):
 606         """ ROOT_PORT is the nearest port to a root bridge.
 607             It is determined by the cost of path, etc. """
 608         root_port = None
 609
 610         for port in self.ports.values():
 611             root_msg = (self.root_priority if root_port is None
 612                         else root_port.designated_priority)
 613             port_msg = port.designated_priority
 614             if port.state is PORT_STATE_DISABLE or port_msg is None:
 615                 continue
 616             if root_msg.root_id.value > port_msg.root_id.value:
 617                 result = SUPERIOR
 618             elif root_msg.root_id.value == port_msg.root_id.value:
 619                 if root_msg.designated_bridge_id is None:
 620                     result = INFERIOR
 621                 else:
 622                     result = Stp.compare_root_path(
 623                         port_msg.root_path_cost,
 624                         root_msg.root_path_cost,
 625                         port_msg.designated_bridge_id.value,
 626                         root_msg.designated_bridge_id.value,
 627                         port_msg.designated_port_id.value,
 628                         root_msg.designated_port_id.value)
 629             else:
 630                 result = INFERIOR
 631
 632             if result is SUPERIOR:
 633                 root_port = port
 634
 635         return root_port
 636
 637     def _select_designated_port(self, root_port):
 638         """ DESIGNATED_PORT is a port of the side near the root bridge
 639             of each link. It is determined by the cost of each path, etc
 640             same as ROOT_PORT. """
 641         d_ports = []
 642         root_msg = root_port.designated_priority
 643
 644         for port in self.ports.values():
 645             port_msg = port.designated_priority
 646             if (port.state is PORT_STATE_DISABLE
 647                     or port.ofport.port_no == root_port.ofport.port_no):
 648                 continue
 649             if (port_msg is None or
 650                     (port_msg.root_id.value != root_msg.root_id.value)):
 651                 d_ports.append(port.ofport.port_no)
 652             else:
 653                 result = Stp.compare_root_path(
 654                     root_msg.root_path_cost,
 655                     port_msg.root_path_cost - port.path_cost,
 656                     self.bridge_id.value,
 657                     port_msg.designated_bridge_id.value,
 658                     port.port_id.value,
 659                     port_msg.designated_port_id.value)
 660                 if result is SUPERIOR:
 661                     d_ports.append(port.ofport.port_no)
 662
 663         return d_ports
 664
 665     def topology_change_notify(self, port_state):
 666         notice = False
 667         if port_state is PORT_STATE_FORWARD:
 668             for port in self.ports.values():
 669                 if port.role is DESIGNATED_PORT:
 670                     notice = True
 671                     break
 672         else:
 673             notice = True
 674
 675         if notice:
 676             self.send_event(EventTopologyChange(self.dp))
 677             if self.is_root_bridge:
 678                 self._transmit_tc_bpdu()
 679             else:
 680                 self._transmit_tcn_bpdu()
 681
 682     def _transmit_tc_bpdu(self):
 683         for port in self.ports.values():
 684             port.transmit_tc_bpdu()
 685
 686     def _transmit_tcn_bpdu(self):
 687         root_port = None
 688         for port in self.ports.values():
 689             if port.role is ROOT_PORT:
 690                 root_port = port
 691                 break
 692         if root_port:
 693             root_port.transmit_tcn_bpdu()
 694
 695     def _forward_tc_bpdu(self, fwd_flg):
 696         for port in self.ports.values():
 697             port.send_tc_flg = fwd_flg
 698
 699
 700 class Port(object):
 701     _DEFAULT_VALUE = {'priority': bpdu.DEFAULT_PORT_PRIORITY,
 702                       'path_cost': bpdu.PORT_PATH_COST_10MB,
 703                       'enable': True}
 704
 705     def __init__(self, dp, logger, config, send_ev_func, timeout_func,
 706                  topology_change_func, bridge_id, bridge_times, ofport):
 707         super(Port, self).__init__()
 708         self.dp = dp
 709         self.logger = logger
 710         self.dpid_str = {'dpid': dpid_to_str(dp.id)}
 711         self.config_enable = config.get('enable',
 712                                         self._DEFAULT_VALUE['enable'])
 713         self.send_event = send_ev_func
 714         self.wait_bpdu_timeout = timeout_func
 715         self.topology_change_notify = topology_change_func
 716         self.ofctl = (OfCtl_v1_0(dp) if dp.ofproto == ofproto_v1_0
 717                       else OfCtl_v1_2later(dp))
 718
 719         # Bridge data
 720         self.bridge_id = bridge_id
 721         # Root bridge data
 722         self.port_priority = None
 723         self.port_times = None
 724         # ofproto_v1_X_parser.OFPPhyPort data
 725         self.ofport = ofport
 726         # Port data
 727         values = self._DEFAULT_VALUE
 728         path_costs = {dp.ofproto.OFPPF_10MB_HD: bpdu.PORT_PATH_COST_10MB,
 729                       dp.ofproto.OFPPF_10MB_FD: bpdu.PORT_PATH_COST_10MB,
 730                       dp.ofproto.OFPPF_100MB_HD: bpdu.PORT_PATH_COST_100MB,
 731                       dp.ofproto.OFPPF_100MB_FD: bpdu.PORT_PATH_COST_100MB,
 732                       dp.ofproto.OFPPF_1GB_HD: bpdu.PORT_PATH_COST_1GB,
 733                       dp.ofproto.OFPPF_1GB_FD: bpdu.PORT_PATH_COST_1GB,
 734                       dp.ofproto.OFPPF_10GB_FD: bpdu.PORT_PATH_COST_10GB}
 735         for rate in sorted(path_costs, reverse=True):
 736             if ofport.curr & rate:
 737                 values['path_cost'] = path_costs[rate]
 738                 break
 739         for key, value in values.items():
 740             values[key] = value
 741         self.port_id = PortId(values['priority'], ofport.port_no)
 742         self.path_cost = values['path_cost']
 743         self.state = (None if self.config_enable else PORT_STATE_DISABLE)
 744         self.role = None
 745         # Receive BPDU data
 746         self.designated_priority = None
 747         self.designated_times = None
 748         # BPDU handling threads
 749         self.send_bpdu_thread = PortThread(self._transmit_bpdu)
 750         self.wait_bpdu_thread = PortThread(self._wait_bpdu_timer)
 751         self.send_tc_flg = None
 752         self.send_tc_timer = None
 753         self.send_tcn_flg = None
 754         self.wait_timer_event = None
 755         # State machine thread
 756         self.state_machine = PortThread(self._state_machine)
 757         self.state_event = None
 758
 759         self.up(DESIGNATED_PORT,
 760                 Priority(bridge_id, 0, None, None),
 761                 bridge_times)
 762
 763         self.state_machine.start()
 764         self.logger.debug('[port=%d] Start port state machine.',
 765                           self.ofport.port_no, extra=self.dpid_str)
 766
 767     def delete(self):
 768         self.state_machine.stop()
 769         self.send_bpdu_thread.stop()
 770         self.wait_bpdu_thread.stop()
 771         if self.state_event is not None:
 772             self.state_event.set()
 773             self.state_event = None
 774         if self.wait_timer_event is not None:
 775             self.wait_timer_event.set()
 776             self.wait_timer_event = None
 777         self.logger.debug('[port=%d] Stop port threads.',
 778                           self.ofport.port_no, extra=self.dpid_str)
 779
 780     def up(self, role, root_priority, root_times):
 781         """ A port is started in the state of LISTEN.  """
 782         self.port_priority = root_priority
 783         self.port_times = root_times
 784
 785         state = (PORT_STATE_LISTEN if self.config_enable
 786                  else PORT_STATE_DISABLE)
 787         self._change_role(role)
 788         self._change_status(state)
 789
 790     def down(self, state, msg_init=False):
 791         """ A port will be in the state of DISABLE or BLOCK,
 792              and be stopped.  """
 793         assert (state is PORT_STATE_DISABLE
 794                 or state is PORT_STATE_BLOCK)
 795         if not self.config_enable:
 796             return
 797
 798         if msg_init:
 799             self.designated_priority = None
 800             self.designated_times = None
 801
 802         self._change_role(DESIGNATED_PORT)
 803         self._change_status(state)
 804
 805     def _state_machine(self):
 806         """ Port state machine.
 807              Change next status when timer is exceeded
 808              or _change_status() method is called."""
 809         role_str = {ROOT_PORT: 'ROOT_PORT          ',
 810                     DESIGNATED_PORT: 'DESIGNATED_PORT    ',
 811                     NON_DESIGNATED_PORT: 'NON_DESIGNATED_PORT'}
 812         state_str = {PORT_STATE_DISABLE: 'DISABLE',
 813                      PORT_STATE_BLOCK: 'BLOCK',
 814                      PORT_STATE_LISTEN: 'LISTEN',
 815                      PORT_STATE_LEARN: 'LEARN',
 816                      PORT_STATE_FORWARD: 'FORWARD'}
 817
 818         if self.state is PORT_STATE_DISABLE:
 819             self.ofctl.set_port_status(self.ofport, self.state)
 820
 821         while True:
 822             self.logger.info('[port=%d] %s / %s', self.ofport.port_no,
 823                              role_str[self.role], state_str[self.state],
 824                              extra=self.dpid_str)
 825
 826             self.state_event = hub.Event()
 827             timer = self._get_timer()
 828             if timer:
 829                 timeout = hub.Timeout(timer)
 830                 try:
 831                     self.state_event.wait()
 832                 except hub.Timeout as t:
 833                     if t is not timeout:
 834                         err_msg = 'Internal error. Not my timeout.'
 835                         raise RyuException(msg=err_msg)
 836                     new_state = self._get_next_state()
 837                     self._change_status(new_state, thread_switch=False)
 838                 finally:
 839                     timeout.cancel()
 840             else:
 841                 self.state_event.wait()
 842
 843             self.state_event = None
 844
 845     def _get_timer(self):
 846         timer = {PORT_STATE_DISABLE: None,
 847                  PORT_STATE_BLOCK: None,
 848                  PORT_STATE_LISTEN: self.port_times.forward_delay,
 849                  PORT_STATE_LEARN: self.port_times.forward_delay,
 850                  PORT_STATE_FORWARD: None}
 851         return timer[self.state]
 852
 853     def _get_next_state(self):
 854         next_state = {PORT_STATE_DISABLE: None,
 855                       PORT_STATE_BLOCK: None,
 856                       PORT_STATE_LISTEN: PORT_STATE_LEARN,
 857                       PORT_STATE_LEARN: (PORT_STATE_FORWARD
 858                                          if (self.role is ROOT_PORT or
 859                                              self.role is DESIGNATED_PORT)
 860                                          else PORT_STATE_BLOCK),
 861                       PORT_STATE_FORWARD: None}
 862         return next_state[self.state]
 863
 864     def _change_status(self, new_state, thread_switch=True):
 865         if new_state is not PORT_STATE_DISABLE:
 866             self.ofctl.set_port_status(self.ofport, new_state)
 867
 868         if(new_state is PORT_STATE_FORWARD
 869            or (self.state is PORT_STATE_FORWARD
 870                and (new_state is PORT_STATE_DISABLE
 871                     or new_state is PORT_STATE_BLOCK))):
 872             self.topology_change_notify(new_state)
 873
 874         if (new_state is PORT_STATE_DISABLE
 875                 or new_state is PORT_STATE_BLOCK):
 876             self.send_tc_flg = False
 877             self.send_tc_timer = None
 878             self.send_tcn_flg = False
 879             self.send_bpdu_thread.stop()
 880         elif new_state is PORT_STATE_LISTEN:
 881             self.send_bpdu_thread.start()
 882
 883         self.state = new_state
 884         self.send_event(EventPortStateChange(self.dp, self))
 885
 886         if self.state_event is not None:
 887             self.state_event.set()
 888             self.state_event = None
 889         if thread_switch:
 890             hub.sleep(0)  # For thread switching.
 891
 892     def _change_role(self, new_role):
 893         if self.role is new_role:
 894             return
 895         self.role = new_role
 896         if (new_role is ROOT_PORT
 897                 or new_role is NON_DESIGNATED_PORT):
 898             self.wait_bpdu_thread.start()
 899         else:
 900             assert new_role is DESIGNATED_PORT
 901             self.wait_bpdu_thread.stop()
 902
 903     def rcv_config_bpdu(self, bpdu_pkt):
 904         # Check received BPDU is superior to currently held BPDU.
 905         root_id = BridgeId(bpdu_pkt.root_priority,
 906                            bpdu_pkt.root_system_id_extension,
 907                            bpdu_pkt.root_mac_address)
 908         root_path_cost = bpdu_pkt.root_path_cost
 909         designated_bridge_id = BridgeId(bpdu_pkt.bridge_priority,
 910                                         bpdu_pkt.bridge_system_id_extension,
 911                                         bpdu_pkt.bridge_mac_address)
 912         designated_port_id = PortId(bpdu_pkt.port_priority,
 913                                     bpdu_pkt.port_number)
 914
 915         msg_priority = Priority(root_id, root_path_cost,
 916                                 designated_bridge_id,
 917                                 designated_port_id)
 918         msg_times = Times(bpdu_pkt.message_age,
 919                           bpdu_pkt.max_age,
 920                           bpdu_pkt.hello_time,
 921                           bpdu_pkt.forward_delay)
 922
 923         rcv_info = Stp.compare_bpdu_info(self.designated_priority,
 924                                          self.designated_times,
 925                                          msg_priority, msg_times)
 926         if rcv_info is SUPERIOR:
 927             self.designated_priority = msg_priority
 928             self.designated_times = msg_times
 929
 930         chk_flg = False
 931         if ((rcv_info is SUPERIOR or rcv_info is REPEATED)
 932                 and (self.role is ROOT_PORT
 933                      or self.role is NON_DESIGNATED_PORT)):
 934             self._update_wait_bpdu_timer()
 935             chk_flg = True
 936         elif rcv_info is INFERIOR and self.role is DESIGNATED_PORT:
 937             chk_flg = True
 938
 939         # Check TopologyChange flag.
 940         rcv_tc = False
 941         if chk_flg:
 942             tc_flag_mask = 0b00000001
 943             tcack_flag_mask = 0b10000000
 944             if bpdu_pkt.flags & tc_flag_mask:
 945                 self.logger.debug('[port=%d] receive TopologyChange BPDU.',
 946                                   self.ofport.port_no, extra=self.dpid_str)
 947                 rcv_tc = True
 948             if bpdu_pkt.flags & tcack_flag_mask:
 949                 self.logger.debug('[port=%d] receive TopologyChangeAck BPDU.',
 950                                   self.ofport.port_no, extra=self.dpid_str)
 951                 if self.send_tcn_flg:
 952                     self.send_tcn_flg = False
 953
 954         return rcv_info, rcv_tc
 955
 956     def _update_wait_bpdu_timer(self):
 957         if self.wait_timer_event is not None:
 958             self.wait_timer_event.set()
 959             self.wait_timer_event = None
 960             self.logger.debug('[port=%d] Wait BPDU timer is updated.',
 961                               self.ofport.port_no, extra=self.dpid_str)
 962         hub.sleep(0)  # For thread switching.
 963
 964     def _wait_bpdu_timer(self):
 965         time_exceed = False
 966
 967         while True:
 968             self.wait_timer_event = hub.Event()
 969             message_age = (self.designated_times.message_age
 970                            if self.designated_times else 0)
 971             timer = self.port_times.max_age - message_age
 972             timeout = hub.Timeout(timer)
 973             try:
 974                 self.wait_timer_event.wait()
 975             except hub.Timeout as t:
 976                 if t is not timeout:
 977                     err_msg = 'Internal error. Not my timeout.'
 978                     raise RyuException(msg=err_msg)
 979                 self.logger.info('[port=%d] Wait BPDU timer is exceeded.',
 980                                  self.ofport.port_no, extra=self.dpid_str)
 981                 time_exceed = True
 982             finally:
 983                 timeout.cancel()
 984                 self.wait_timer_event = None
 985
 986             if time_exceed:
 987                 break
 988
 989         if time_exceed:  # Bridge.recalculate_spanning_tree
 990             hub.spawn(self.wait_bpdu_timeout)
 991
 992     def _transmit_bpdu(self):
 993         while True:
 994             # Send config BPDU packet if port role is DESIGNATED_PORT.
 995             if self.role == DESIGNATED_PORT:
 996                 now = datetime.datetime.today()
 997                 if self.send_tc_timer and self.send_tc_timer < now:
 998                     self.send_tc_timer = None
 999                     self.send_tc_flg = False
1000
1001                 if not self.send_tc_flg:
1002                     flags = 0b00000000
1003                     log_msg = '[port=%d] Send Config BPDU.'
1004                 else:
1005                     flags = 0b00000001
1006                     log_msg = '[port=%d] Send TopologyChange BPDU.'
1007                 bpdu_data = self._generate_config_bpdu(flags)
1008                 self.ofctl.send_packet_out(self.ofport.port_no, bpdu_data)
1009                 self.logger.debug(log_msg, self.ofport.port_no,
1010                                   extra=self.dpid_str)
1011
1012             # Send Topology Change Notification BPDU until receive Ack.
1013             if self.send_tcn_flg:
1014                 bpdu_data = self._generate_tcn_bpdu()
1015                 self.ofctl.send_packet_out(self.ofport.port_no, bpdu_data)
1016                 self.logger.debug('[port=%d] Send TopologyChangeNotify BPDU.',
1017                                   self.ofport.port_no, extra=self.dpid_str)
1018
1019             hub.sleep(self.port_times.hello_time)
1020
1021     def transmit_tc_bpdu(self):
1022         """ Set send_tc_flg to send Topology Change BPDU. """
1023         if not self.send_tc_flg:
1024             timer = datetime.timedelta(seconds=self.port_times.max_age
1025                                        + self.port_times.forward_delay)
1026             self.send_tc_timer = datetime.datetime.today() + timer
1027             self.send_tc_flg = True
1028
1029     def transmit_ack_bpdu(self):
1030         """ Send Topology Change Ack BPDU. """
1031         ack_flags = 0b10000001
1032         bpdu_data = self._generate_config_bpdu(ack_flags)
1033         self.ofctl.send_packet_out(self.ofport.port_no, bpdu_data)
1034
1035     def transmit_tcn_bpdu(self):
1036         self.send_tcn_flg = True
1037
1038     def _generate_config_bpdu(self, flags):
1039         src_mac = self.ofport.hw_addr
1040         dst_mac = bpdu.BRIDGE_GROUP_ADDRESS
1041         length = (bpdu.bpdu._PACK_LEN + bpdu.ConfigurationBPDUs.PACK_LEN
1042                   + llc.llc._PACK_LEN + llc.ControlFormatU._PACK_LEN)
1043
1044         e = ethernet.ethernet(dst_mac, src_mac, length)
1045         l = llc.llc(llc.SAP_BPDU, llc.SAP_BPDU, llc.ControlFormatU())
1046         b = bpdu.ConfigurationBPDUs(
1047             flags=flags,
1048             root_priority=self.port_priority.root_id.priority,
1049             root_mac_address=self.port_priority.root_id.mac_addr,
1050             root_path_cost=self.port_priority.root_path_cost + self.path_cost,
1051             bridge_priority=self.bridge_id.priority,
1052             bridge_mac_address=self.bridge_id.mac_addr,
1053             port_priority=self.port_id.priority,
1054             port_number=self.ofport.port_no,
1055             message_age=self.port_times.message_age + 1,
1056             max_age=self.port_times.max_age,
1057             hello_time=self.port_times.hello_time,
1058             forward_delay=self.port_times.forward_delay)
1059
1060         pkt = packet.Packet()
1061         pkt.add_protocol(e)
1062         pkt.add_protocol(l)
1063         pkt.add_protocol(b)
1064         pkt.serialize()
1065
1066         return pkt.data
1067
1068     def _generate_tcn_bpdu(self):
1069         src_mac = self.ofport.hw_addr
1070         dst_mac = bpdu.BRIDGE_GROUP_ADDRESS
1071         length = (bpdu.bpdu._PACK_LEN
1072                   + bpdu.TopologyChangeNotificationBPDUs.PACK_LEN
1073                   + llc.llc._PACK_LEN + llc.ControlFormatU._PACK_LEN)
1074
1075         e = ethernet.ethernet(dst_mac, src_mac, length)
1076         l = llc.llc(llc.SAP_BPDU, llc.SAP_BPDU, llc.ControlFormatU())
1077         b = bpdu.TopologyChangeNotificationBPDUs()
1078
1079         pkt = packet.Packet()
1080         pkt.add_protocol(e)
1081         pkt.add_protocol(l)
1082         pkt.add_protocol(b)
1083         pkt.serialize()
1084
1085         return pkt.data
1086
1087
1088 class PortThread(object):
1089     def __init__(self, function):
1090         super(PortThread, self).__init__()
1091         self.function = function
1092         self.thread = None
1093
1094     def start(self):
1095         self.stop()
1096         self.thread = hub.spawn(self.function)
1097
1098     def stop(self):
1099         if self.thread is not None:
1100             hub.kill(self.thread)
1101             hub.joinall([self.thread])
1102             self.thread = None
1103
1104
1105 class BridgeId(object):
1106     def __init__(self, priority, system_id_extension, mac_addr):
1107         super(BridgeId, self).__init__()
1108         self.priority = priority
1109         self.system_id_extension = system_id_extension
1110         self.mac_addr = mac_addr
1111         self.value = bpdu.ConfigurationBPDUs.encode_bridge_id(
1112             priority, system_id_extension, mac_addr)
1113
1114
1115 class PortId(object):
1116     def __init__(self, priority, port_no):
1117         super(PortId, self).__init__()
1118         self.priority = priority
1119         self.port_no = port_no
1120         self.value = bpdu.ConfigurationBPDUs.encode_port_id(priority, port_no)
1121
1122
1123 class Priority(object):
1124     def __init__(self, root_id, root_path_cost,
1125                  designated_bridge_id, designated_port_id):
1126         super(Priority, self).__init__()
1127         self.root_id = root_id
1128         self.root_path_cost = root_path_cost
1129         self.designated_bridge_id = designated_bridge_id
1130         self.designated_port_id = designated_port_id
1131
1132
1133 class Times(object):
1134     def __init__(self, message_age, max_age, hello_time, forward_delay):
1135         super(Times, self).__init__()
1136         self.message_age = message_age
1137         self.max_age = max_age
1138         self.hello_time = hello_time
1139         self.forward_delay = forward_delay
1140
1141
1142 class OfCtl_v1_0(object):
1143     def __init__(self, dp):
1144         super(OfCtl_v1_0, self).__init__()
1145         self.dp = dp
1146
1147     def send_packet_out(self, out_port, data):
1148         actions = [self.dp.ofproto_parser.OFPActionOutput(out_port, 0)]
1149         self.dp.send_packet_out(buffer_id=self.dp.ofproto.OFP_NO_BUFFER,
1150                                 in_port=self.dp.ofproto.OFPP_CONTROLLER,
1151                                 actions=actions, data=data)
1152
1153     def set_port_status(self, port, state):
1154         ofproto_parser = self.dp.ofproto_parser
1155         mask = 0b1111111
1156         msg = ofproto_parser.OFPPortMod(self.dp, port.port_no, port.hw_addr,
1157                                         PORT_CONFIG_V1_0[state], mask,
1158                                         port.advertised)
1159         self.dp.send_msg(msg)
1160
1161
1162 class OfCtl_v1_2later(OfCtl_v1_0):
1163     def __init__(self, dp):
1164         super(OfCtl_v1_2later, self).__init__(dp)
1165
1166     def set_port_status(self, port, state):
1167         ofp = self.dp.ofproto
1168         parser = self.dp.ofproto_parser
1169         config = {ofproto_v1_2: PORT_CONFIG_V1_2,
1170                   ofproto_v1_3: PORT_CONFIG_V1_3}
1171
1172         # Only turn on the relevant bits defined on OpenFlow 1.2+, otherwise
1173         # some switch that follows the specification strictly will report
1174         # OFPPMFC_BAD_CONFIG error.
1175         mask = 0b1100101
1176         msg = parser.OFPPortMod(self.dp, port.port_no, port.hw_addr,
1177                                 config[ofp][state], mask, port.advertised)
1178         self.dp.send_msg(msg)
1179
1180         if config[ofp][state] & ofp.OFPPC_NO_PACKET_IN:
1181             self.add_no_pkt_in_flow(port.port_no)
1182         else:
1183             self.del_no_pkt_in_flow(port.port_no)
1184
1185     def add_bpdu_pkt_in_flow(self):
1186         ofp = self.dp.ofproto
1187         parser = self.dp.ofproto_parser
1188
1189         match = parser.OFPMatch(eth_dst=bpdu.BRIDGE_GROUP_ADDRESS)
1190         actions = [parser.OFPActionOutput(ofp.OFPP_CONTROLLER,
1191                                           ofp.OFPCML_NO_BUFFER)]
1192         inst = [parser.OFPInstructionActions(ofp.OFPIT_APPLY_ACTIONS,
1193                                              actions)]
1194         mod = parser.OFPFlowMod(self.dp, priority=BPDU_PKT_IN_PRIORITY,
1195                                 match=match, instructions=inst)
1196         self.dp.send_msg(mod)
1197
1198     def add_no_pkt_in_flow(self, in_port):
1199         parser = self.dp.ofproto_parser
1200
1201         match = parser.OFPMatch(in_port=in_port)
1202         mod = parser.OFPFlowMod(self.dp, priority=NO_PKT_IN_PRIORITY,
1203                                 match=match)
1204         self.dp.send_msg(mod)
1205
1206     def del_no_pkt_in_flow(self, in_port):
1207         ofp = self.dp.ofproto
1208         parser = self.dp.ofproto_parser
1209
1210         match = parser.OFPMatch(in_port=in_port)
1211         mod = parser.OFPFlowMod(self.dp, command=ofp.OFPFC_DELETE_STRICT,
1212                                 out_port=ofp.OFPP_ANY, out_group=ofp.OFPG_ANY,
1213                                 priority=NO_PKT_IN_PRIORITY, match=match)
1214         self.dp.send_msg(mod)