예제 #1
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 def __init__(self, config, sender, logger, lbal):
     # Maps of ports.
     self.logger = logger
     self.sender = sender
     self.config = config
     self.lbal = lbal
     self.fm_builder = FlowModMsgBuilder(0, self.config.flanc_auth["key"])
     lbal.lb_policy(self.config.edge_core)
예제 #2
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    def xstart(self):
        # Start all clients/listeners/whatevs
        self.logger.info("Starting controller for participant")

        # ExaBGP Peering Instance
        self.bgp_instance = self.cfg.get_bgp_instance()

        # Route server client, Reference monitor client, Arp Proxy client
        self.xrs_client = self.cfg.get_xrs_client(self.logger)
	self.xrs_client.send({'msgType': 'hello', 'id': self.cfg.id, 'peers_in': self.cfg.peers_in, 'peers_out': self.cfg.peers_out, 'ports': self.cfg.get_ports()})

        self.arp_client = self.cfg.get_arp_client(self.logger)
        self.arp_client.send({'msgType': 'hello', 'macs': self.cfg.get_macs()})

        self.refmon_client = self.cfg.get_refmon_client(self.logger)
         # class for building flow mod msgs to the reference monitor
        self.fm_builder = FlowModMsgBuilder(self.id, self.refmon_client.key)

        # Send flow rules for initial policies to the SDX's Reference Monitor
        self.initialize_dataplane()
        self.push_dp()

        # Start the event handlers
        ps_thread_arp = Thread(target=self.start_eh_arp)
        ps_thread_arp.daemon = True
        ps_thread_arp.start()

        ps_thread_xrs = Thread(target=self.start_eh_xrs)
        ps_thread_xrs.daemon = True
        ps_thread_xrs.start()

        ps_thread_arp.join()
        ps_thread_xrs.join()
        self.logger.debug("Return from ps_thread.join()")
예제 #3
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 def __init__(self, config, sender, logger, lbal):
     # Maps of ports.
     self.logger = logger
     self.sender = sender
     self.config = config
     self.lbal = lbal
     self.fm_builder = FlowModMsgBuilder(0, self.config.flanc_auth["key"])
     lbal.lb_policy(self.config.edge_core)
예제 #4
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    def push_dp(self):
        '''
        (1) Check if there are any policies queued to be pushed
        (2) Send the queued policies to reference monitor
        '''

        self.logger.debug("Pushing current flow mod queue:")

        # it is crucial that dp_queued is traversed chronologically
        fm_builder = FlowModMsgBuilder(self.id, self.refmon_client.key)
        for flowmod in self.dp_queued:
            self.logger.debug("MOD: " + str(flowmod))
            if (flowmod['mod_type'] == 'remove'):
                fm_builder.delete_flow_mod(flowmod['mod_type'],
                                           flowmod['rule_type'],
                                           flowmod['cookie'][0],
                                           flowmod['cookie'][1])
            elif (flowmod['mod_type'] == 'insert'):
                fm_builder.add_flow_mod(**flowmod)
            else:
                self.logger.error("Unhandled flow type: " +
                                  flowmod['mod_type'])
                continue
            self.dp_pushed.append(flowmod)

        self.dp_queued = []
        self.refmon_client.send(json.dumps(fm_builder.get_msg()))
예제 #5
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 def __init__(self, config, flows, sender, logger, **kwargs):
     self.logger = logger
     self.sender = sender
     self.config = config
     table_id = None
     self.fm_builder = FlowModMsgBuilder(0, self.config.flanc_auth["key"])
     try:
         table_id =  config.tables['access-control']
     except KeyError, e:
         print "Access Control table does not exists in the sdx_global.cfg file! - Add a table named %s." % str(e)
예제 #6
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    def xstart(self):
        # Start all clients/listeners/whatevs
        self.logger.info("Starting controller for participant")

        # ExaBGP Peering Instance
        self.bgp_instance = self.cfg.get_bgp_instance()

        # Route server client, Reference monitor client, Arp Proxy client
        self.xrs_client = self.cfg.get_xrs_client(self.logger)
        self.xrs_client.send({
            'msgType': 'hello',
            'id': self.cfg.id,
            'peers_in': self.cfg.peers_in,
            'peers_out': self.cfg.peers_out,
            'ports': self.cfg.get_ports()
        })

        self.arp_client = self.cfg.get_arp_client(self.logger)
        self.arp_client.send({'msgType': 'hello', 'macs': self.cfg.get_macs()})

        self.refmon_client = self.cfg.get_refmon_client(self.logger)
        # class for building flow mod msgs to the reference monitor
        self.fm_builder = FlowModMsgBuilder(self.id, self.refmon_client.key)

        # Send flow rules for initial policies to the SDX's Reference Monitor
        self.initialize_dataplane()
        self.push_dp()

        # Start the event handlers
        ps_thread_arp = Thread(target=self.start_eh_arp)
        ps_thread_arp.daemon = True
        ps_thread_arp.start()

        ps_thread_xrs = Thread(target=self.start_eh_xrs)
        ps_thread_xrs.daemon = True
        ps_thread_xrs.start()

        ps_thread_arp.join()
        ps_thread_xrs.join()
        self.logger.debug("Return from ps_thread.join()")
예제 #7
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    def start(self):
        # Start all clients/listeners/whatevs
        self.logger.info("Starting controller for participant")

        # ExaBGP Peering Instance
        self.bgp_instance = self.cfg.get_bgp_instance()
        self.logger.debug("Trace: Started controller for participant")

        # Route server client, Reference monitor client, Arp Proxy client
        self.xrs_client = self.cfg.get_xrs_client(self.logger)
        self.arp_client = self.cfg.get_arp_client(self.logger)
        self.refmon_client = self.cfg.get_refmon_client(self.logger)
         # class for building flow mod msgs to the reference monitor
        self.fm_builder = FlowModMsgBuilder(self.id, self.refmon_client.key)

        # Send flow rules for initial policies to the SDX's Reference Monitor
        self.initialize_dataplane()
        self.push_dp()

        # Start the event handler
        eh_socket = self.cfg.get_eh_info()
        self.listener_eh = Listener(eh_socket, authkey=None)
        self.start_eh()
예제 #8
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 def __init__(self, config, flows, sender, logger, **kwargs):
     self.logger = logger
     self.sender = sender
     self.config = config
     # collector is a class to execute queries for network status.
     self.collector = StatsCollector(
         InfluxDBClient(host=INFLUXDB_HOST,
                        port=INFLUXDB_PORT,
                        username=INFLUXDB_USER,
                        password=INFLUXDB_PASS,
                        database=INFLUXDB_DB,
                        timeout=10))
     table_id = None
     self.fm_builder = FlowModMsgBuilder(0, self.config.flanc_auth["key"])
     try:
         table_id = config.tables['monitor']
     except KeyError, e:
         print "Monitoring table does not exists in the sdx_global.cfg file! - Add a table named %s." % str(
             e)
예제 #9
0
    def push_dp(self):
        '''
        (1) Check if there are any policies queued to be pushed
        (2) Send the queued policies to reference monitor
        '''

        self.logger.debug("Pushing current flow mod queue:")

        # it is crucial that dp_queued is traversed chronologically
        fm_builder = FlowModMsgBuilder(self.id, self.refmon_client.key)
        for flowmod in self.dp_queued:
            self.logger.debug("MOD: "+str(flowmod))
            if (flowmod['mod_type'] == 'remove'):
                fm_builder.delete_flow_mod(flowmod['mod_type'], flowmod['rule_type'], flowmod['cookie'][0], flowmod['cookie'][1])
            elif (flowmod['mod_type'] == 'insert'):
                fm_builder.add_flow_mod(**flowmod)
            else:
                self.logger.error("Unhandled flow type: " + flowmod['mod_type'])
                continue
            self.dp_pushed.append(flowmod)

        self.dp_queued = []
        self.refmon_client.send(json.dumps(fm_builder.get_msg()))
예제 #10
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class ParticipantController(object):
    def __init__(self, id, config_file, policy_file, logger):
        # participant id
        self.id = id
        # print ID for logging
        self.logger = logger

        # used to signal termination
        self.run = True
        self.prefix_lock = {}

        # Initialize participant params
        self.cfg = PConfig(config_file, self.id)
        # Vmac encoding mode
        # self.cfg.vmac_mode = config_file["vmac_mode"]
        # Dataplane mode---multi table or multi switch
        # self.cfg.dp_mode = config_file["dp_mode"]


        self.load_policies(policy_file)

        # The port 0 MAC is used for tagging outbound rules as belonging to us
        self.port0_mac = self.cfg.port0_mac

        self.nexthop_2_part = self.cfg.get_nexthop_2_part()

        # VNHs related params
        self.num_VNHs_in_use = 0
        self.VNH_2_prefix = {}
        self.prefix_2_VNH = {}


        # Superset related params
        if self.cfg.isSupersetsMode():
            self.supersets = SuperSets(self, self.cfg.vmac_options)
        else:
            # TODO: create similar class and variables for MDS
            self.mds = None

        # Keep track of flow rules pushed
        self.dp_pushed = []
        # Keep track of flow rules which are scheduled to be pushed
        self.dp_queued = []


    def start(self):
        # Start all clients/listeners/whatevs
        self.logger.info("Starting controller for participant")

        # ExaBGP Peering Instance
        self.bgp_instance = self.cfg.get_bgp_instance()
        self.logger.debug("Trace: Started controller for participant")

        # Route server client, Reference monitor client, Arp Proxy client
        self.xrs_client = self.cfg.get_xrs_client(self.logger)
        self.arp_client = self.cfg.get_arp_client(self.logger)
        self.refmon_client = self.cfg.get_refmon_client(self.logger)
         # class for building flow mod msgs to the reference monitor
        self.fm_builder = FlowModMsgBuilder(self.id, self.refmon_client.key)

        # Send flow rules for initial policies to the SDX's Reference Monitor
        self.initialize_dataplane()
        self.push_dp()

        # Start the event handler
        eh_socket = self.cfg.get_eh_info()
        self.listener_eh = Listener(eh_socket, authkey=None)
        self.start_eh()
        #ps_thread = Thread(target=self.start_eh)
        #ps_thread.daemon = True
        #ps_thread.start()


    def load_policies(self, policy_file):
        # Load policies from file

        with open(policy_file, 'r') as f:
            self.policies = json.load(f)

        port_count = len(self.cfg.ports)

        # sanitize the input policies
        if 'inbound' in self.policies:
            for policy in self.policies['inbound']:
                if 'action' not in policy:
                    continue
                if 'fwd' in policy['action'] and int(policy['action']['fwd']) >= port_count:
                    policy['action']['fwd'] = 0


    def initialize_dataplane(self):
        "Read the config file and update the queued policy variable"

        self.logger.info("Initializing inbound rules")

        final_switch = "main-in"
        if self.cfg.isMultiTableMode():
            final_switch = "main-out"

        self.init_vnh_assignment()

        rule_msgs = init_inbound_rules(self.id, self.policies,
                                        self.supersets, final_switch)
        self.logger.debug("Rule Messages INBOUND:: "+str(rule_msgs))

        rule_msgs2 = init_outbound_rules(self, self.id, self.policies,
                                        self.supersets, final_switch)
        self.logger.debug("Rule Messages OUTBOUND:: "+str(rule_msgs2))

        if 'changes' in rule_msgs2:
            if 'changes' not in rule_msgs:
                rule_msgs['changes'] = []
            rule_msgs['changes'] += rule_msgs2['changes']

        #TODO: Initialize Outbound Policies from RIB
        self.logger.debug("Rule Messages:: "+str(rule_msgs))
        if 'changes' in rule_msgs:
            self.dp_queued.extend(rule_msgs["changes"])


    def push_dp(self):
        '''
        (1) Check if there are any policies queued to be pushed
        (2) Send the queued policies to reference monitor
        '''

        self.logger.debug("Pushing current flow mod queue:")

        # it is crucial that dp_queued is traversed chronologically
        for flowmod in self.dp_queued:
            self.logger.debug("MOD: "+str(flowmod))
            self.fm_builder.add_flow_mod(**flowmod)
            self.dp_pushed.append(flowmod)

        self.dp_queued = []
        self.refmon_client.send(json.dumps(self.fm_builder.get_msg()))


    def stop(self):
        "Stop the Participants' SDN Controller"
        self.logger.info("Stopping Controller. "+str(self.logger_info))

        # Signal Termination and close blocking listener
        self.run = False
        conn = Client(self.cfg.get_eh_info(), authkey=None)
        conn.send("terminate")
        conn.close()

        # TODO: confirm that this isn't silly
        self.xrs_client = None
        self.refmon_client = None
        self.arp_client = None

        # TODO: Think of better way of terminating this listener
        self.listener_eh.close()


    def start_eh(self):
        '''Socket listener for network events '''
        self.logger.info("Event Handler started.")

        while self.run:
            self.logger.debug("EH waiting for connection...")
            conn_eh = self.listener_eh.accept()

            tmp = conn_eh.recv()

            if tmp != "terminate":
                self.logger.debug("EH established connection...")

                data = json.loads(tmp)

                self.logger.debug("Event received of type "+str(data.keys()))

                # Starting a thread for independently processing each incoming network event
                event_processor_thread = Thread(target = self.process_event, args = [data])
                event_processor_thread.daemon = True
                event_processor_thread.start()

                # Send a message back to the sender.
                reply = "Event Received"
                conn_eh.send(reply)
            conn_eh.close()

    def process_event(self, data):
        "Locally process each incoming network event"


        if 'bgp' in data:
            self.logger.debug("Event Received: BGP Update.")
            route = data['bgp']
            # Process the incoming BGP updates from XRS
            #self.logger.debug("BGP Route received: "+str(route)+" "+str(type(route)))
            self.process_bgp_route(route)

        elif 'policy' in data:
            # Process the event requesting change of participants' policies
            self.logger.debug("Event Received: Policy change.")
            change_info = data['policy']
            self.process_policy_changes(change_info)

        elif 'arp' in data:
            (requester_srcmac, requested_vnh) = tuple(data['arp'])
            self.logger.debug("Event Received: ARP request for IP "+str(requested_vnh))
            self.process_arp_request(requester_srcmac, requested_vnh)

        else:
            self.logger.warn("UNKNOWN EVENT TYPE RECEIVED: "+str(data))


    def process_policy_changes(self, change_info):
        "Process the changes in participants' policies"
        # TODO: Implement the logic of dynamically changing participants' outbound and inbound policy
        '''
            change_info =
            {
                'removal_cookies' : [cookie1, ...], # Cookies of deleted policies
                'new_policies' :
                {
                    <policy file format>
                }

            }
        '''
        # remove flow rules for the old policies
        removal_msgs = []

        '''
        for cookie in change_info['removal_cookies']:
            mod =  {"rule_type":"outbound", "priority":0,
                    "match":match_args , "action":{},
                    "cookie":cookie, "mod_type":"remove"}
            removal_msgs.append(mod)
        '''

        self.dp_queued.extend(removal_msgs)


        # add flow rules for the new policies
        if self.cfg.isSupersetsMode():
            dp_msgs = ss_process_policy_change(self.supersets, add_policies, remove_policies, policies,
                                                self.port_count, self.port0_mac)
        else:
            dp_msgs = []

        self.dp_queued.extend(dp_msgs)

        self.push_dp()

        return 0




    def process_arp_request(self, part_mac, vnh):
        vmac = ""
        if self.cfg.isSupersetsMode():
            vmac = self.supersets.get_vmac(self, vnh)
        else:
            vmac = "whoa" # MDS vmac goes here

        arp_responses = list()

        # if this is gratuitous, send a reply to the part's ID
        if part_mac is None:
            gratuitous = True
            # set fields appropriately for gratuitous arps
            i = 0
            for port in self.cfg.ports:
                eth_dst = vmac_part_port_match(self.id, i, self.supersets, False)
                arp_responses.append({'SPA': vnh, 'TPA': vnh,
                                   'SHA': vmac, 'THA': vmac,
                                   'eth_src': vmac, 'eth_dst': eth_dst})
                i += 1

        else: # if it wasn't gratuitous
            gratuitous = False
            # dig up the IP of the target participant
            for port in self.cfg.ports:
                if part_mac == port["MAC"]:
                    part_ip = port["IP"]
                    break

            # set field appropriately for arp responses
            arp_responses.append({'SPA': vnh, 'TPA': part_ip,
                        'SHA': vmac, 'THA': part_mac,
                        'eth_src': vmac, 'eth_dst': part_mac})

        if gratuitous:
            self.logger.debug("Sending Gratuitious ARP: "+str(arp_responses))
        else:
            self.logger.debug("Sending ARP Response: "+str(arp_responses))

        for arp_response in arp_responses:
            self.arp_client.send(json.dumps(arp_response))

    def getlock(self, prefixes):
        prefixes.sort()
        hsh = "-".join(prefixes)
        if hsh not in self.prefix_lock:
            #self.logger.debug("First Lock:: "+str(hsh))
            self.prefix_lock[hsh] = RLock()
        #else:
            #self.logger.debug("Repeat :: "+str(hsh))
        return self.prefix_lock[hsh]

    def process_bgp_route(self, route):
        "Process each incoming BGP advertisement"
        tstart = time.time()

        prefixes = get_prefixes_from_announcements(route)
        with self.getlock(prefixes):
            reply = ''
            # Map to update for each prefix in the route advertisement.
            updates = self.bgp_instance.update(route)
            #self.logger.debug("process_bgp_route:: "+str(updates))
            # TODO: This step should be parallelized
            # TODO: The decision process for these prefixes is going to be same, we
            # should think about getting rid of such redundant computations.
            for update in updates:
                self.bgp_instance.decision_process_local(update)
                self.vnh_assignment(update)

            if TIMING:
                elapsed = time.time() - tstart
                self.logger.debug("Time taken for decision process: "+str(elapsed))
                tstart = time.time()

            if self.cfg.isSupersetsMode():
            ################## SUPERSET RESPONSE TO BGP ##################
                # update supersets
                "Map the set of BGP updates to a list of superset expansions."
                ss_changes, ss_changed_prefs = self.supersets.update_supersets(self, updates)

                if TIMING:
                    elapsed = time.time() - tstart
                    self.logger.debug("Time taken to update supersets: "+str(elapsed))
                    tstart = time.time()

                # ss_changed_prefs are prefixes for which the VMAC bits have changed
                # these prefixes must have gratuitous arps sent
                garp_required_vnhs = [self.prefix_2_VNH[prefix] for prefix in ss_changed_prefs]

                "If a recomputation event was needed, wipe out the flow rules."
                if ss_changes["type"] == "new":
                    self.logger.debug("Wiping outbound rules.")
                    wipe_msgs = msg_clear_all_outbound(self.policies, self.port0_mac)
                    self.dp_queued.extend(wipe_msgs)

                    #if a recomputation was needed, all VMACs must be reARPed
                    # TODO: confirm reARPed is a word
                    garp_required_vnhs = self.VNH_2_prefix.keys()

                if len(ss_changes['changes']) > 0:

                    self.logger.debug("Supersets have changed: "+str(ss_changes))

                    "Map the superset changes to a list of new flow rules."
                    flow_msgs = update_outbound_rules(ss_changes, self.policies,
                            self.supersets, self.port0_mac)

                    self.logger.debug("Flow msgs: "+str(flow_msgs))
                    "Dump the new rules into the dataplane queue."
                    self.dp_queued.extend(flow_msgs)

                if TIMING:
                    elapsed = time.time() - tstart
                    self.logger.debug("Time taken to deal with ss_changes: "+str(elapsed))
                    tstart = time.time()

            ################## END SUPERSET RESPONSE ##################

            else:
                # TODO: similar logic for MDS
                self.logger.debug("Creating ctrlr messages for MDS scheme")

            self.push_dp()

            if TIMING:
                elapsed = time.time() - tstart
                self.logger.debug("Time taken to push dp msgs: "+str(elapsed))
                tstart = time.time()

            changed_vnhs, announcements = self.bgp_instance.bgp_update_peers(updates,
                    self.prefix_2_VNH, self.cfg.ports)

            """ Combine the VNHs which have changed BGP default routes with the
                VNHs which have changed supersets.
            """

            changed_vnhs = set(changed_vnhs)
            changed_vnhs.update(garp_required_vnhs)

            # Send gratuitous ARP responses for all them
            for vnh in changed_vnhs:
                self.process_arp_request(None, vnh)

            # Tell Route Server that it needs to announce these routes
            for announcement in announcements:
                # TODO: Complete the logic for this function
                self.send_announcement(announcement)

            if TIMING:
                elapsed = time.time() - tstart
                self.logger.debug("Time taken to send garps/announcements: "+str(elapsed))
                tstart = time.time()

            return reply


    def send_announcement(self, announcement):
        "Send the announcements to XRS"
        self.logger.debug("Sending announcements to XRS. "+str(type(announcement)))

        self.xrs_client.send(json.dumps(announcement))


    def vnh_assignment(self, update):
        "Assign VNHs for the advertised prefixes"
        if self.cfg.isSupersetsMode():
            " Superset"
            # TODO: Do we really need to assign a VNH for each advertised prefix?
            if ('announce' in update):
                prefix = update['announce'].prefix

                if (prefix not in self.prefix_2_VNH):
                    # get next VNH and assign it the prefix
                    self.num_VNHs_in_use += 1
                    vnh = str(self.cfg.VNHs[self.num_VNHs_in_use])

                    self.prefix_2_VNH[prefix] = vnh
                    self.VNH_2_prefix[vnh] = prefix
        else:
            "Disjoint"
            # TODO: @Robert: Place your logic here for VNH assignment for MDS scheme
            self.logger.debug("VNH assignment called for disjoint vmac_mode")


    def init_vnh_assignment(self):
        "Assign VNHs for the advertised prefixes"
        if self.cfg.isSupersetsMode():
            " Superset"
            # TODO: Do we really need to assign a VNH for each advertised prefix?
            #self.bgp_instance.rib["local"].dump()
            prefixes = self.bgp_instance.rib["local"].get_prefixes()
            #print 'init_vnh_assignment: prefixes:', prefixes
            #print 'init_vnh_assignment: prefix_2_VNH:', self.prefix_2_VNH
            for prefix in prefixes:
                if (prefix not in self.prefix_2_VNH):
                    # get next VNH and assign it the prefix
                    self.num_VNHs_in_use += 1
                    vnh = str(self.cfg.VNHs[self.num_VNHs_in_use])

                    self.prefix_2_VNH[prefix] = vnh
                    self.VNH_2_prefix[vnh] = prefix
        else:
            "Disjoint"
            # TODO: @Robert: Place your logic here for VNH assignment for MDS scheme
            self.logger.debug("VNH assignment called for disjoint vmac_mode")
예제 #11
0
class ParticipantController(object):
    def __init__(self, id, config_file, policy_file, logger):
        # participant id
        self.id = id
        # print ID for logging
        self.logger = logger

        # used to signal termination
        self.run = True
        self.prefix_lock = {}

        # Initialize participant params
        self.cfg = PConfig(config_file, self.id)
        # Vmac encoding mode
        # self.cfg.vmac_mode = config_file["vmac_mode"]
        # Dataplane mode---multi table or multi switch
        # self.cfg.dp_mode = config_file["dp_mode"]


        self.policies = self.load_policies(policy_file)

        # The port 0 MAC is used for tagging outbound rules as belonging to us
        self.port0_mac = self.cfg.port0_mac

        self.nexthop_2_part = self.cfg.get_nexthop_2_part()

        # VNHs related params
        self.num_VNHs_in_use = 0
        self.VNH_2_prefix = {}
        self.prefix_2_VNH = {}


        # Superset related params
        if self.cfg.isSupersetsMode():
            self.supersets = SuperSets(self, self.cfg.vmac_options)
        else:
            # TODO: create similar class and variables for MDS
            self.mds = None

        # Keep track of flow rules pushed
        self.dp_pushed = []
        # Keep track of flow rules which are scheduled to be pushed
        self.dp_queued = []


    def xstart(self):
        # Start all clients/listeners/whatevs
        self.logger.info("Starting controller for participant")

        # ExaBGP Peering Instance
        self.bgp_instance = self.cfg.get_bgp_instance()

        # Route server client, Reference monitor client, Arp Proxy client
        self.xrs_client = self.cfg.get_xrs_client(self.logger)
        self.xrs_client.send({'msgType': 'hello', 'id': self.cfg.id, 'peers_in': self.cfg.peers_in, 'peers_out': self.cfg.peers_out, 'ports': self.cfg.get_ports()})

        self.arp_client = self.cfg.get_arp_client(self.logger)
        self.arp_client.send({'msgType': 'hello', 'macs': self.cfg.get_macs()})

        # Participant API for dynamic route updates
        self.participant_api = self.cfg.get_participant_api(self.id, self.logger)
        self.participant_api.start(self)

        # RefMon Instance
        self.refmon_client = self.cfg.get_refmon_client(self.logger)
        
         # class for building flow mod msgs to the reference monitor
        self.fm_builder = FlowModMsgBuilder(self.id, self.refmon_client.key)

        # Send flow rules for initial policies to the SDX's Reference Monitor
        self.initialize_dataplane()
        self.push_dp()

        # Start the event handlers
        ps_thread_arp = Thread(target=self.start_eh_arp)
        ps_thread_arp.daemon = True
        ps_thread_arp.start()

        ps_thread_xrs = Thread(target=self.start_eh_xrs)
        ps_thread_xrs.daemon = True
        ps_thread_xrs.start()

        ps_thread_arp.join()
        ps_thread_xrs.join()
        self.logger.debug("Return from ps_thread.join()")

    def sanitize_policies(self, policies):

        port_count = len(self.cfg.ports)

        # sanitize the input policies
        if 'inbound' in policies:
            for policy in policies['inbound']:
                if 'action' not in policy:
                    continue
                if 'fwd' in policy['action'] and int(policy['action']['fwd']) >= port_count:
                    policy['action']['fwd'] = 0

        return policies


    def load_policies(self, policy_file):
        # Load policies from file

        with open(policy_file, 'r') as f:
            policies = json.load(f)

        return self.sanitize_policies(policies)


    def initialize_dataplane(self):
        "Read the config file and update the queued policy variable"

        self.logger.info("Initializing inbound rules")

        final_switch = "main-in"
        if self.cfg.isMultiTableMode():
            final_switch = "main-out"

        self.init_vnh_assignment()

        rule_msgs = init_inbound_rules(self.id, self.policies,
                                        self.supersets, final_switch)
        self.logger.debug("Rule Messages INBOUND:: "+str(rule_msgs))

        rule_msgs2 = init_outbound_rules(self, self.id, self.policies,
                                        self.supersets, final_switch)
        self.logger.debug("Rule Messages OUTBOUND:: "+str(rule_msgs2))

        if 'changes' in rule_msgs2:
            if 'changes' not in rule_msgs:
                rule_msgs['changes'] = []
            rule_msgs['changes'] += rule_msgs2['changes']

        #TODO: Initialize Outbound Policies from RIB
        self.logger.debug("Rule Messages:: "+str(rule_msgs))
        if 'changes' in rule_msgs:
            self.dp_queued.extend(rule_msgs["changes"])


    def push_dp(self):
        '''
        (1) Check if there are any policies queued to be pushed
        (2) Send the queued policies to reference monitor
        '''

        # it is crucial that dp_queued is traversed chronologically
        for flowmod in self.dp_queued:
            self.fm_builder.add_flow_mod(**flowmod)
            self.dp_pushed.append(flowmod)

        # reset queue
        self.dp_queued = []

        self.refmon_client.send(json.dumps(self.fm_builder.get_msg()))
        
        # reset flow_mods after send - self.flow_mods = []
        self.fm_builder.reset_flow_mod()


    def stop(self):
        "Stop the Participants' SDN Controller"

        self.logger.info("Stopping Controller.")

        # Signal Termination and close blocking listener
        self.run = False

        # TODO: confirm that this isn't silly
        #self.refmon_client = None


    def start_eh_arp(self):
        self.logger.info("ARP Event Handler started.")

        while self.run:
            # need to poll since recv() will not detect close from this end
            # and need some way to shutdown gracefully.
            if not self.arp_client.poll(1):
                continue
            try:
                tmp = self.arp_client.recv()
            except EOFError:
                break

            data = json.loads(tmp)
            self.logger.debug("ARP Event received: %s", data)

            # Starting a thread for independently processing each incoming network event
            event_processor_thread = Thread(target=self.process_event, args=(data,))
            event_processor_thread.daemon = True
            event_processor_thread.start()

        self.arp_client.close()
        self.logger.debug("Exiting start_eh_arp")


    def start_eh_xrs(self):
        self.logger.info("XRS Event Handler started.")

        while self.run:
            # need to poll since recv() will not detect close from this end
            # and need some way to shutdown gracefully.
            if not self.xrs_client.poll(1):
                continue
            try:
                tmp = self.xrs_client.recv()
            except EOFError:
                break

            data = json.loads(tmp)
            self.logger.debug("XRS Event received: %s", data)

            self.process_event(data)

        self.xrs_client.close()
        self.logger.debug("Exiting start_eh_xrs")


    def process_event(self, data, mod_type=None):  
        "Locally process each incoming network event"

        if 'bgp' in data:
            self.logger.debug("Event Received: BGP Update.")
            route = data['bgp']
            # Process the incoming BGP updates from XRS
            #self.logger.debug("BGP Route received: "+str(route)+" "+str(type(route)))
            self.process_bgp_route(route)

        elif 'policy' in data:
            # Process the event requesting change of participants' policies
            self.logger.debug("Event Received: Policy change.")
            change_info = data['policy']
            for element in change_info:
                if 'remove' in element:
                    self.process_policy_changes(element['remove'], 'remove')
                    #self.logger.debug("PART_Test: REMOVE: %s" % element)
                if 'insert' in element:
                    self.process_policy_changes(element['insert'], 'insert')
                    #self.logger.debug("PART_Test: INSERT: %s" % element)

        elif 'arp' in data:
            (requester_srcmac, requested_vnh) = tuple(data['arp'])
            self.logger.debug("Event Received: ARP request for IP "+str(requested_vnh))
            self.process_arp_request(requester_srcmac, requested_vnh)

        else:
            self.logger.warn("UNKNOWN EVENT TYPE RECEIVED: "+str(data))


    def process_policy_changes(self, change_info, mod_type):
        # idea to remove flow rules for the old policies with cookies
        '''
        removal_msgs = []
        for element in change_info:

            if 'removal_cookies' in element:
        
                for cookie in element['removal_cookies']:
                    cookie_id = (cookie['cookie'],65535)
                    match_args = cookie['match']
                    mod =  {"rule_type":"inbound", "priority":4,"match":{} , "action":{}, "cookie":cookie_id, "mod_type":"remove"}
                    removal_msgs.append(mod)
        
        self.dp_queued.extend(removal_msgs)
        '''

        # json file format for change_info - mod_type = remove or insert
        '''
        {
            "policy": [
            {
                mod_type: [ 
        
        # change_info begin

                    {
                        "inbound": [
                            { cookie1 ... match ... action }
                            { cookie2 ... match ... action }
                        ]
                    }

                    {
                        "outbound": [
                            { cookie1 ... match ... action }
                            { cookie2 ... match ... action }
                        ]
                    }

        # change_info end
                
                ]           // end mod_type-array
            }, 
            
            {
                mod_type: ...

            }

            ]               // end policy-array
        }
        '''

        policies = self.sanitize_policies(change_info)

        final_switch = "main-in"
        if self.cfg.isMultiTableMode():
            final_switch = "main-out"

        #self.init_vnh_assignment() // not used
        inbound_policies = {}
        outbound_policies = {}
        
        for element in policies:
            if 'inbound' in element:
                inbound_policies = element
            if 'outbound' in element:
                outbound_policies = element

        #self.logger.debug("PART_Test: INBOUND: %s" % inbound_policies)
        #self.logger.debug("PART_Test: OUTBOUND: %s" % outbound_policies)

        rule_msgs = init_inbound_rules(self.id, inbound_policies,
                                        self.supersets, final_switch)

        rule_msgs2 = init_outbound_rules(self, self.id, outbound_policies,
                                        self.supersets, final_switch)

        if 'changes' in rule_msgs2:
            if 'changes' not in rule_msgs:
                rule_msgs['changes'] = []
            rule_msgs['changes'] += rule_msgs2['changes']


        for rule in rule_msgs['changes']:
            rule['mod_type'] = mod_type


        #self.logger.debug("PART_Test: Rule Msgs: %s" % rule_msgs)

        if 'changes' in rule_msgs:
            self.dp_queued.extend(rule_msgs["changes"])

        self.push_dp()


    def process_arp_request(self, part_mac, vnh):
        vmac = ""
        if self.cfg.isSupersetsMode():
            vmac = self.supersets.get_vmac(self, vnh)
        else:
            vmac = "whoa" # MDS vmac goes here

        arp_responses = list()

        # if this is gratuitous, send a reply to the part's ID
        if part_mac is None:
            gratuitous = True
            # set fields appropriately for gratuitous arps
            i = 0
            for port in self.cfg.ports:
                eth_dst = vmac_part_port_match(self.id, i, self.supersets, False)
                arp_responses.append({'SPA': vnh, 'TPA': vnh,
                                   'SHA': vmac, 'THA': vmac,
                                   'eth_src': vmac, 'eth_dst': eth_dst})
                i += 1

        else: # if it wasn't gratuitous
            gratuitous = False
            # dig up the IP of the target participant
            for port in self.cfg.ports:
                if part_mac == port["MAC"]:
                    part_ip = port["IP"]
                    break

            # set field appropriately for arp responses
            arp_responses.append({'SPA': vnh, 'TPA': part_ip,
                        'SHA': vmac, 'THA': part_mac,
                        'eth_src': vmac, 'eth_dst': part_mac})

        if gratuitous:
            self.logger.debug("Sending Gratuitious ARP: "+str(arp_responses))
        else:
            self.logger.debug("Sending ARP Response: "+str(arp_responses))

        for arp_response in arp_responses:
            arp_response['msgType'] = 'garp'
            self.arp_client.send(arp_response)


    def getlock(self, prefixes):
        prefixes.sort()
        hsh = "-".join(prefixes)
        if hsh not in self.prefix_lock:
            #self.logger.debug("First Lock:: "+str(hsh))
            self.prefix_lock[hsh] = RLock()
        #else:
            #self.logger.debug("Repeat :: "+str(hsh))
        return self.prefix_lock[hsh]

    def process_bgp_route(self, route):
        "Process each incoming BGP advertisement"
        tstart = time.time()

        # Map to update for each prefix in the route advertisement.
        updates = self.bgp_instance.update(route)
        #self.logger.debug("process_bgp_route:: "+str(updates))
        # TODO: This step should be parallelized
        # TODO: The decision process for these prefixes is going to be same, we
        # should think about getting rid of such redundant computations.
        for update in updates:
            self.bgp_instance.decision_process_local(update)
            self.vnh_assignment(update)

        if TIMING:
            elapsed = time.time() - tstart
            self.logger.debug("Time taken for decision process: "+str(elapsed))
            tstart = time.time()

        if self.cfg.isSupersetsMode():
            ################## SUPERSET RESPONSE TO BGP ##################
            # update supersets
            "Map the set of BGP updates to a list of superset expansions."
            ss_changes, ss_changed_prefs = self.supersets.update_supersets(self, updates)

            if TIMING:
                elapsed = time.time() - tstart
                self.logger.debug("Time taken to update supersets: "+str(elapsed))
                tstart = time.time()

            # ss_changed_prefs are prefixes for which the VMAC bits have changed
            # these prefixes must have gratuitous arps sent
            garp_required_vnhs = [self.prefix_2_VNH[prefix] for prefix in ss_changed_prefs]

            "If a recomputation event was needed, wipe out the flow rules."
            if ss_changes["type"] == "new":
                self.logger.debug("Wiping outbound rules.")
                wipe_msgs = msg_clear_all_outbound(self.policies, self.port0_mac)
                self.dp_queued.extend(wipe_msgs)

                #if a recomputation was needed, all VMACs must be reARPed
                # TODO: confirm reARPed is a word
                garp_required_vnhs = self.VNH_2_prefix.keys()

            if len(ss_changes['changes']) > 0:

                self.logger.debug("Supersets have changed: "+str(ss_changes))

                "Map the superset changes to a list of new flow rules."
                flow_msgs = update_outbound_rules(ss_changes, self.policies,
                        self.supersets, self.port0_mac)

                self.logger.debug("Flow msgs: "+str(flow_msgs))
                "Dump the new rules into the dataplane queue."
                self.dp_queued.extend(flow_msgs)

            if TIMING:
                elapsed = time.time() - tstart
                self.logger.debug("Time taken to deal with ss_changes: "+str(elapsed))
                tstart = time.time()

        ################## END SUPERSET RESPONSE ##################

        else:
            # TODO: similar logic for MDS
            self.logger.debug("Creating ctrlr messages for MDS scheme")

        self.push_dp()

        if TIMING:
            elapsed = time.time() - tstart
            self.logger.debug("Time taken to push dp msgs: "+str(elapsed))
            tstart = time.time()

        changed_vnhs, announcements = self.bgp_instance.bgp_update_peers(updates,
                self.prefix_2_VNH, self.cfg.ports)

        """ Combine the VNHs which have changed BGP default routes with the
            VNHs which have changed supersets.
        """

        changed_vnhs = set(changed_vnhs)
        changed_vnhs.update(garp_required_vnhs)

        # Send gratuitous ARP responses for all them
        for vnh in changed_vnhs:
            self.process_arp_request(None, vnh)

        # Tell Route Server that it needs to announce these routes
        for announcement in announcements:
            # TODO: Complete the logic for this function
            self.send_announcement(announcement)

        if TIMING:
            elapsed = time.time() - tstart
            self.logger.debug("Time taken to send garps/announcements: "+str(elapsed))
            tstart = time.time()


    def send_announcement(self, announcement):
        "Send the announcements to XRS"
	self.logger.debug("Sending announcements to XRS: %s", announcement)
	self.xrs_client.send({'msgType': 'bgp', 'announcement': announcement})


    def vnh_assignment(self, update):
        "Assign VNHs for the advertised prefixes"
        if self.cfg.isSupersetsMode():
            " Superset"
            # TODO: Do we really need to assign a VNH for each advertised prefix?
            if ('announce' in update):
                prefix = update['announce'].prefix

                if (prefix not in self.prefix_2_VNH):
                    # get next VNH and assign it the prefix
                    self.num_VNHs_in_use += 1
                    vnh = str(self.cfg.VNHs[self.num_VNHs_in_use])

                    self.prefix_2_VNH[prefix] = vnh
                    self.VNH_2_prefix[vnh] = prefix
        else:
            "Disjoint"
            # TODO: @Robert: Place your logic here for VNH assignment for MDS scheme
            self.logger.debug("VNH assignment called for disjoint vmac_mode")


    def init_vnh_assignment(self):
        "Assign VNHs for the advertised prefixes"
        if self.cfg.isSupersetsMode():
            " Superset"
            # TODO: Do we really need to assign a VNH for each advertised prefix?
            #self.bgp_instance.rib["local"].dump()
            prefixes = self.bgp_instance.rib["local"].get_prefixes()
            #print 'init_vnh_assignment: prefixes:', prefixes
            #print 'init_vnh_assignment: prefix_2_VNH:', self.prefix_2_VNH
            for prefix in prefixes:
                if (prefix not in self.prefix_2_VNH):
                    # get next VNH and assign it the prefix
                    self.num_VNHs_in_use += 1
                    vnh = str(self.cfg.VNHs[self.num_VNHs_in_use])

                    self.prefix_2_VNH[prefix] = vnh
                    self.VNH_2_prefix[vnh] = prefix
        else:
            "Disjoint"
            # TODO: @Robert: Place your logic here for VNH assignment for MDS scheme
            self.logger.debug("VNH assignment called for disjoint vmac_mode")
예제 #12
0
class Umbrella(object):
    def __init__(self, config, sender, logger, lbal):
        # Maps of ports.
        self.logger = logger
        self.sender = sender
        self.config = config
        self.lbal = lbal
        self.fm_builder = FlowModMsgBuilder(0, self.config.flanc_auth["key"])
        lbal.lb_policy(self.config.edge_core)

    # Format to umbrella fabric mac address.
    # core_port: core switch port connected to the edge
    # edge_port: edge port connected to a participant
    def create_umbrella_mac(self, core_port, edge_port):
        # First byte: core switch port connected to the
        # destination's edge switch.
        mac_1st_byte = '{}'.format('0' + format(core_port, 'x') if len(
            hex(core_port)) == 3 else format(core_port, 'x'))
        # Second byte: one of the edges ports connected to the
        # destination peer.
        mac_2nd_byte = '{}'.format('0' + format(edge_port, 'x') if len(
            hex(edge_port)) == 3 else format(edge_port, 'x'))
        mac = '%s:%s:00:00:00:00' % (mac_1st_byte, mac_2nd_byte)
        return mac

    def ARP_match(self, arp_tpa):
        #"eth_dst": ETH_BROADCAST_MAC,
        match = {"eth_type": ETH_TYPE_ARP, "arp_tpa": arp_tpa}
        return match

    def l2_match(self, eth_dst):
        match = {"eth_dst": eth_dst}
        return match

    def handle_ARP(self, rule_type):
        # peers are in the same edge
        for dp in self.config.edge_peers:
            peers = self.config.edge_peers[dp]
            for peer in peers:
                out_port = peers[peer]
                match = self.ARP_match(peer.ip)
                action = {"set_eth_dst": peer.mac, "fwd": [out_port]}
                self.fm_builder.add_flow_mod("insert", rule_type, ARP_PRIORITY,
                                             match, action,
                                             self.config.dpid_2_name[dp])

        #TODO: peers are in different edges. Edges connected directly.
        # Or create a different class to handle topologies like this

        # peers are in different edges. Edges are connected through cores.
        for edge in self.config.edge_peers:
            for target_dp, hosts in self.config.edge_peers.iteritems():
                if target_dp == edge:
                    continue
                else:
                    for host in hosts:
                        core, out_port_to_core = self.lbal.lb_action(edge)
                        core_port_to_target = self.config.core_edge[core][
                            target_dp]
                        edge_port = self.config.edge_peers[target_dp][host]
                        match = self.ARP_match(host.ip)
                        actions = {
                            "set_eth_dst":
                            self.create_umbrella_mac(core_port_to_target,
                                                     edge_port),
                            "fwd": [out_port_to_core]
                        }
                        self.fm_builder.add_flow_mod(
                            "insert", rule_type, ARP_PRIORITY, match, actions,
                            self.config.dpid_2_name[edge])

    def handle_ingress_l2(self, rule_type):
        # peers are in the same edge
        for dp in self.config.edge_peers:
            peers = self.config.edge_peers[dp]
            for peer in peers:
                out_port = peers[peer]
                match = self.l2_match(peer.mac)
                action = {"fwd": [out_port]}
                self.fm_builder.add_flow_mod("insert", rule_type,
                                             FORWARDING_PRIORITY, match,
                                             action,
                                             self.config.dpid_2_name[dp])

        for edge in self.config.edge_peers:
            for target_dp, hosts in self.config.edge_peers.iteritems():
                if target_dp == edge:
                    continue
                else:
                    for host in hosts:
                        # need to install one flow per core for the load balancing
                        # TODO: find a better way to do it. It is too ugly now
                        for core in self.config.core_edge:
                            out_port_to_core = self.config.edge_core[edge][
                                core]
                            core_port_to_target = self.config.core_edge[core][
                                target_dp]
                            edge_port = self.config.edge_peers[target_dp][host]
                            match = self.l2_match(host.mac)
                            match["metadata"] = core
                            actions = {
                                "set_eth_dst":
                                self.create_umbrella_mac(
                                    core_port_to_target, edge_port),
                                "fwd": [out_port_to_core]
                            }
                            self.fm_builder.add_flow_mod(
                                "insert", rule_type, FORWARDING_PRIORITY,
                                match, actions, self.config.dpid_2_name[edge])

    def create_egress_match(self, edge_port):
        mac_2nd_byte = '{}'.format('0' + format(edge_port, 'x') if len(
            hex(edge_port)) == 3 else format(edge_port, 'x'))
        eth_dst = ('00:%s:00:00:00:00' % (mac_2nd_byte), "00:ff:00:00:00:00")
        match = {"eth_dst": eth_dst}
        return match

    def handle_egress(self, rule_type):
        for dp in self.config.edge_peers:
            peers = self.config.edge_peers[dp]
            for peer in peers:
                # Flow match destination MAC is
                #based on the edge port connected
                edge_port = self.config.edge_peers[dp][peer]
                match = self.create_egress_match(edge_port)
                peer_mac = peer.mac
                action = {"set_eth_dst": peer_mac, "fwd": [edge_port]}
                self.fm_builder.add_flow_mod("insert", rule_type,
                                             FORWARDING_PRIORITY, match,
                                             action,
                                             self.config.dpid_2_name[dp])

    def create_core_match(self, out_port):
        mac_1st_byte = '{}'.format('0' + format(out_port, 'x') if len(
            hex(out_port)) == 3 else format(out_port, 'x'))
        eth_dst = ('%s:00:00:00:00:00' % (mac_1st_byte), "ff:00:00:00:00:00")
        match = {"eth_dst": eth_dst}
        return match

    def handle_core_switches(self, rule_type):
        for core in self.config.core_edge:
            for edge in self.config.core_edge[core]:
                # Flow match is based on the core port connected to the
                # edge switch
                out_port = self.config.core_edge[core][edge]
                match = self.create_core_match(out_port)
                action = {"fwd": [out_port]}

                self.fm_builder.add_flow_mod("insert", rule_type,
                                             FORWARDING_PRIORITY, match,
                                             action,
                                             self.config.dpid_2_name[core])

    # Just send load balancer flows to umbrella.
    def handle_load_balancer(self, rule_type):

        # multi check
        match_byte1 = [0, 0, 0, "00000001"]
        match_byte2 = [0, 0, 0, "00000001"]

        # create id_matches - init core multi match with id_matches
        id_matcher1, id_matcher2 = self.lbal.init_multi_match(
            match_byte1, match_byte2)
        self.lbal.set_core_multi_match(self.config.cores,
                                       [id_matcher1, id_matcher2])

        # Rule for every Edge
        for edge in self.config.edge_core:
            # Rule to every Core
            for core in self.config.cores:
                # Decision for Match is core_id
                core_id = self.config.cores[core]

                # multi check field(s)
                match, metadata = self.lbal.get_ip_multi_match(
                    core_id, ['ipv4_src', 'ipv4_dst'])

                # Build Instruction Meta-Information and Goto-Table
                instructions = {"meta": metadata, "fwd": ["umbrella-edge"]}

                # Send for every Core to every Edge
                self.fm_builder.add_flow_mod("insert", rule_type, LB_PRIORITY,
                                             match, instructions,
                                             self.config.dpid_2_name[edge])
            # Need to handle VNH MACS.
            # TODO: Add group to support fast failover.
            match = {"eth_type": ETH_TYPE_ARP}
            # Picking the last core from the last loop. Should be replaced
            # with a group later
            metadata = [self.config.cores[core], METADATA_MASK]
            instructions = {"meta": metadata, "fwd": ["umbrella-edge"]}
            self.fm_builder.add_flow_mod("insert", rule_type, LB_PRIORITY,
                                         match, instructions,
                                         self.config.dpid_2_name[edge])

    def start(self):
        self.logger.info('start')
        self.handle_ARP("umbrella-edge")
        self.handle_ingress_l2("umbrella-edge")
        self.handle_core_switches("umbrella-core")
        self.handle_egress("umbrella-edge")
        self.handle_load_balancer("load-balancer")
        self.sender.send(self.fm_builder.get_msg())
        self.logger.info('sent flow mods to reference monitor')
예제 #13
0
class Umbrella(object):
    def __init__(self, config, sender, logger, lbal):
        # Maps of ports.
        self.logger = logger
        self.sender = sender
        self.config = config
        self.lbal = lbal
        self.fm_builder = FlowModMsgBuilder(0, self.config.flanc_auth["key"])
        lbal.lb_policy(self.config.edge_core)
    # Format to umbrella fabric mac address.
    # core_port: core switch port connected to the edge
    # edge_port: edge port connected to a participant
    def create_umbrella_mac(self, core_port, edge_port):
        # First byte: core switch port connected to the 
        # destination's edge switch.
        mac_1st_byte = '{}'.format('0' + format(core_port, 'x') if len(hex(core_port)) == 3 else format(core_port, 'x'))
        # Second byte: one of the edges ports connected to the
        # destination peer.
        mac_2nd_byte = '{}'.format('0' + format(edge_port, 'x') if len(hex(edge_port)) == 3 else format(edge_port, 'x'))
        mac = '%s:%s:00:00:00:00' % (mac_1st_byte, mac_2nd_byte)
        return mac

    def ARP_match(self, arp_tpa):
        #"eth_dst": ETH_BROADCAST_MAC, 
         match = {"eth_type": ETH_TYPE_ARP, "arp_tpa":arp_tpa}
         return match

    def l2_match(self, eth_dst):
        match = {"eth_dst":eth_dst}
        return match

    def handle_ARP(self, rule_type):
        # peers are in the same edge
        for dp in self.config.edge_peers:
            peers = self.config.edge_peers[dp]
            for peer in peers:
                out_port = peers[peer]
                match = self.ARP_match(peer.ip)
                action = {"set_eth_dst":peer.mac, "fwd": [out_port]}
                self.fm_builder.add_flow_mod("insert", rule_type, ARP_PRIORITY, match, action, self.config.dpid_2_name[dp])

        #TODO: peers are in different edges. Edges connected directly.
        # Or create a different class to handle topologies like this 

        # peers are in different edges. Edges are connected through cores.
        for edge in self.config.edge_peers:
            for target_dp, hosts in self.config.edge_peers.iteritems():
                if target_dp == edge:
                    continue
                else:
                    for host in hosts:
                        core, out_port_to_core = self.lbal.lb_action(edge) 
                        core_port_to_target = self.config.core_edge[core][target_dp]
                        edge_port = self.config.edge_peers[target_dp][host]
                        match = self.ARP_match(host.ip)
                        actions = {"set_eth_dst": self.create_umbrella_mac(core_port_to_target, edge_port), "fwd": [out_port_to_core]}
                        self.fm_builder.add_flow_mod("insert", rule_type, ARP_PRIORITY, match, actions, self.config.dpid_2_name[edge]) 

    def handle_ingress_l2(self, rule_type):
        # peers are in the same edge
        for dp in self.config.edge_peers:
            peers = self.config.edge_peers[dp]
            for peer in peers:
                out_port = peers[peer]
                match = self.l2_match(peer.mac)
                action = {"fwd": [out_port]}
                self.fm_builder.add_flow_mod("insert", rule_type, FORWARDING_PRIORITY, match, action, self.config.dpid_2_name[dp])
        
        for edge in self.config.edge_peers:
            for target_dp, hosts in self.config.edge_peers.iteritems():
                if target_dp == edge:
                    continue
                else:
                    for host in hosts:
                    # need to install one flow per core for the load balancing
                    # TODO: find a better way to do it. It is too ugly now
                        for core in self.config.core_edge:
                            out_port_to_core = self.config.edge_core[edge][core] 
                            core_port_to_target = self.config.core_edge[core][target_dp]
                            edge_port = self.config.edge_peers[target_dp][host]
                            match = self.l2_match(host.mac)
                            match["metadata"] = core
                            actions = {"set_eth_dst": self.create_umbrella_mac(core_port_to_target, edge_port), "fwd": [out_port_to_core]}
                            self.fm_builder.add_flow_mod("insert", rule_type, FORWARDING_PRIORITY, match, actions, self.config.dpid_2_name[edge]) 

    def create_egress_match(self, edge_port):
        mac_2nd_byte = '{}'.format('0' + format(edge_port, 'x') if len(hex(edge_port)) == 3 else format(edge_port, 'x'))
        eth_dst = ('00:%s:00:00:00:00' % (mac_2nd_byte), "00:ff:00:00:00:00")
        match = {"eth_dst":eth_dst}
        return match

    def handle_egress(self, rule_type):
        for dp in self.config.edge_peers:
            peers = self.config.edge_peers[dp]
            for peer in peers:
                # Flow match destination MAC is 
                #based on the edge port connected
                edge_port = self.config.edge_peers[dp][peer]
                match = self.create_egress_match(edge_port)
                peer_mac = peer.mac
                action = {"set_eth_dst": peer_mac, "fwd": [edge_port]}
                self.fm_builder.add_flow_mod("insert", rule_type, FORWARDING_PRIORITY, match, action, self.config.dpid_2_name[dp]) 

    def create_core_match(self, out_port):
        mac_1st_byte = '{}'.format('0' + format(out_port, 'x') if len(hex(out_port)) == 3 else format(out_port, 'x'))
        eth_dst = ('%s:00:00:00:00:00' % (mac_1st_byte), "ff:00:00:00:00:00")
        match = {"eth_dst": eth_dst}
        return match

    def handle_core_switches(self, rule_type):
        for core in self.config.core_edge:
            for edge in self.config.core_edge[core]:
                # Flow match is based on the core port connected to the
                # edge switch
                out_port = self.config.core_edge[core][edge]
                match = self.create_core_match(out_port)
                action = {"fwd": [out_port]}

                self.fm_builder.add_flow_mod("insert", rule_type, FORWARDING_PRIORITY, match, action, self.config.dpid_2_name[core] )

    # Just send load balancer flows to umbrella. 
    def handle_load_balancer(self, rule_type):
        
        # multi check
        match_byte1 = [0, 0, 0, "00000001"]
        match_byte2 = [0, 0, 0, "00000001"]
        
        # create id_matches - init core multi match with id_matches
        id_matcher1, id_matcher2 = self.lbal.init_multi_match(match_byte1, match_byte2)
        self.lbal.set_core_multi_match(self.config.cores, [id_matcher1, id_matcher2])

        # Rule for every Edge
        for edge in self.config.edge_core:
            # Rule to every Core
            for core in self.config.cores:            
                # Decision for Match is core_id
                core_id = self.config.cores[core]

                # multi check field(s)
                match, metadata = self.lbal.get_ip_multi_match(core_id, ['ipv4_src','ipv4_dst'])

                # Build Instruction Meta-Information and Goto-Table
                instructions = {"meta": metadata, "fwd": ["umbrella-edge"]}

                # Send for every Core to every Edge
                self.fm_builder.add_flow_mod("insert", rule_type, LB_PRIORITY, match, instructions, self.config.dpid_2_name[edge]) 
            # Need to handle VNH MACS. 
            # TODO: Add group to support fast failover.
            match = {"eth_type": ETH_TYPE_ARP}
            # Picking the last core from the last loop. Should be replaced 
            # with a group later
            metadata = [self.config.cores[core], METADATA_MASK] 
            instructions = {"meta": metadata, "fwd": ["umbrella-edge"]}
            self.fm_builder.add_flow_mod("insert", rule_type, LB_PRIORITY, match, instructions, self.config.dpid_2_name[edge]) 

    def start(self):
        self.logger.info('start')
        self.handle_ARP("umbrella-edge")
        self.handle_ingress_l2("umbrella-edge")
        self.handle_core_switches("umbrella-core")
        self.handle_egress("umbrella-edge")
        self.handle_load_balancer("load-balancer")
        self.sender.send(self.fm_builder.get_msg())
        self.logger.info('sent flow mods to reference monitor')