Example #1
0
class GYController(PolicyMixin, MagmaController):
    """
    GYController

    The GY controller installs flows for enforcement of GY final actions, this
    includes redirection and QoS(currently not supported)
    """
    APP_NAME = "gy"
    APP_TYPE = ControllerType.LOGICAL

    def __init__(self, *args, **kwargs):
        super(GYController, self).__init__(*args, **kwargs)
        self._config = kwargs['config']
        self.tbl_num = self._service_manager.get_table_num(self.APP_NAME)
        self.next_main_table = self._service_manager.get_next_table_num(
            self.APP_NAME)
        self.next_service_table = self._service_manager.get_next_table_num(
            EnforcementStatsController.APP_NAME)
        self._enforcement_stats_tbl = self._service_manager.get_table_num(
            EnforcementStatsController.APP_NAME)
        self.loop = kwargs['loop']
        self._msg_hub = MessageHub(self.logger)
        self._internal_ip_allocator = kwargs['internal_ip_allocator']
        self._redirect_scratch = \
            self._service_manager.allocate_scratch_tables(self.APP_NAME, 2)[0]
        self._mac_rewr = \
            self._service_manager.INTERNAL_MAC_IP_REWRITE_TBL_NUM
        self._bridge_ip_address = kwargs['config']['bridge_ip_address']
        self._clean_restart = kwargs['config']['clean_restart']
        self._qos_mgr = None
        self._setup_type = self._config['setup_type']
        self._redirect_manager = \
            RedirectionManager(
                self._bridge_ip_address,
                self.logger,
                self.tbl_num,
                self._service_manager.get_table_num(EGRESS),
                self._redirect_scratch,
                self._session_rule_version_mapper
            )
        if self._setup_type == 'CWF':
            self._redirect_manager.set_cwf_args(
                internal_ip_allocator=kwargs['internal_ip_allocator'],
                arp=kwargs['app_futures']['arpd'],
                mac_rewrite=self._mac_rewr,
                bridge_name=kwargs['config']['bridge_name'],
                egress_table=self._service_manager.get_table_num(EGRESS)
            )

    def initialize_on_connect(self, datapath):
        """
        Install the default flows on datapath connect event.

        Args:
            datapath: ryu datapath struct
        """
        self._datapath = datapath
        self._qos_mgr = QosManager(datapath, self.loop, self._config)
        self._qos_mgr.setup()

        self._delete_all_flows(datapath)
        self._install_default_flows(datapath)

    def deactivate_rules(self, imsi, ip_addr, rule_ids):
        """
        Deactivate flows for a subscriber. If only imsi is present, delete all
        rule flows for a subscriber (i.e. end its session). If rule_ids are
        present, delete the rule flows for that subscriber.

        Args:
            imsi (string): subscriber id
            rule_ids (list of strings): policy rule ids
        """
        if not self.init_finished:
            self.logger.error('Pipelined is not initialized')
            return RuleModResult.FAILURE

        if self._datapath is None:
            self.logger.error('Datapath not initialized')
            return

        if not imsi:
            self.logger.error('No subscriber specified')
            return

        if not rule_ids:
            self._deactivate_flows_for_subscriber(imsi, ip_addr)
        else:
            for rule_id in rule_ids:
                self._deactivate_flow_for_rule(imsi, ip_addr, rule_id)

    def cleanup_state(self):
        pass

    def _deactivate_flows_for_subscriber(self, imsi, ip_addr):
        """
        Deactivate all rules for a subscriber, ending any enforcement

        Args:
            imsi (string): subscriber id
            ip_addr(IPAddress): session IP address
        """
        match = MagmaMatch(imsi=encode_imsi(imsi))
        flows.delete_flow(self._datapath, self.tbl_num, match)
        self._redirect_manager.deactivate_flows_for_subscriber(self._datapath,
                                                               imsi)
        self._qos_mgr.remove_subscriber_qos(imsi)
        self._remove_he_flows(ip_addr, None)

    def _deactivate_flow_for_rule(self, imsi, ip_addr, rule_id):
        """
        Deactivate a specific rule using the flow cookie for a subscriber

        Args:
            imsi (string): subscriber id
            rule_id (string): policy rule id
        """
        try:
            num = self._rule_mapper.get_rule_num(rule_id)
        except KeyError:
            self.logger.error('Could not find rule id %s', rule_id)
            return
        cookie, mask = (num, flows.OVS_COOKIE_MATCH_ALL)
        match = MagmaMatch(imsi=encode_imsi(imsi))
        flows.delete_flow(self._datapath, self.tbl_num, match,
                          cookie=cookie, cookie_mask=mask)
        self._redirect_manager.deactivate_flow_for_rule(self._datapath, imsi,
                                                        num)
        self._qos_mgr.remove_subscriber_qos(imsi, num)
        self._remove_he_flows(ip_addr, rule_id)

    def _install_flow_for_rule(self, imsi, msisdn:bytes, uplink_tunnel: int, ip_addr, apn_ambr, rule):
        """
        Install a flow to get stats for a particular rule. Flows will match on
        IMSI, cookie (the rule num), in/out direction

        Args:
            imsi (string): subscriber to install rule for
            ip_addr (string): subscriber session ipv4 address
            apn_ambr (integer): maximum bandwidth for non-GBR EPS bearers
            rule (PolicyRule): policy rule proto
        """
        if rule.redirect.support == rule.redirect.ENABLED:
            self._install_redirect_flow(imsi, ip_addr, rule)
            return RuleModResult.SUCCESS

        if not rule.flow_list:
            self.logger.error('The flow list for imsi %s, rule.id - %s'
                              'is empty, this shoudn\'t happen', imsi, rule.id)
            return RuleModResult.FAILURE

        flow_adds = []
        try:
            flow_adds = self._get_rule_match_flow_msgs(imsi, msisdn, uplink_tunnel, ip_addr, apn_ambr, rule)
        except FlowMatchError:
            return RuleModResult.FAILURE

        chan = self._msg_hub.send(flow_adds, self._datapath)
        return self._wait_for_rule_responses(imsi, ip_addr, rule, chan)

    def _get_default_flow_msgs_for_subscriber(self, *_):
        return None

    def _install_default_flow_for_subscriber(self, *_):
        pass

    def _delete_all_flows(self, datapath):
        flows.delete_all_flows_from_table(datapath, self.tbl_num)
        flows.delete_all_flows_from_table(datapath, self._redirect_scratch)
        flows.delete_all_flows_from_table(datapath, self._mac_rewr)

    def _install_default_flows(self, datapath):
        """
        For each direction set the default flows to just forward to next app.
        The enforcement flows for each subscriber would be added when the
        IP session is created, by reaching out to the controller/PCRF.

        Args:
            datapath: ryu datapath struct
        """
        match = MagmaMatch()
        flows.add_resubmit_next_service_flow(
            datapath, self.tbl_num, match, [],
            priority=flows.MINIMUM_PRIORITY,
            resubmit_table=self.next_main_table)

    def _install_redirect_flow(self, imsi, ip_addr, rule):
        rule_num = self._rule_mapper.get_or_create_rule_num(rule.id)
        rule_version = self._session_rule_version_mapper.get_version(imsi,
                                                                     ip_addr,
                                                                     rule.id)
        priority = rule.priority
        # TODO currently if redirection is enabled we ignore other flows
        # from rule.flow_list, confirm that this is the expected behaviour
        redirect_request = RedirectionManager.RedirectRequest(
            imsi=imsi,
            ip_addr=ip_addr.address.decode('utf-8'),
            rule=rule,
            rule_num=rule_num,
            rule_version=rule_version,
            priority=priority)
        try:
            if self._setup_type == 'CWF':
                self._redirect_manager.setup_cwf_redirect(
                    self._datapath, self.loop, redirect_request)
            else:
                self._redirect_manager.setup_lte_redirect(
                    self._datapath, self.loop, redirect_request)
            return RuleModResult.SUCCESS
        except RedirectException as err:
            self.logger.error(
                'Redirect Exception for imsi %s, rule.id - %s : %s',
                imsi, rule.id, err
            )
            return RuleModResult.FAILURE

    def _install_default_flows_if_not_installed(self, datapath,
            existing_flows: List[OFPFlowStats]) -> List[OFPFlowStats]:
        """
        For each direction set the default flows to just forward to next app.
        The enforcement flows for each subscriber would be added when the
        IP session is created, by reaching out to the controller/PCRF.
        If default flows are already installed, do nothing.

        Args:
            datapath: ryu datapath struct
        Returns:
            The list of flows that remain after inserting default flows
        """
        match = MagmaMatch()

        msg = flows.get_add_resubmit_next_service_flow_msg(
            datapath, self.tbl_num, match, [],
            priority=flows.MINIMUM_PRIORITY,
            resubmit_table=self.next_main_table)

        msgs, remaining_flows = self._msg_hub \
            .filter_msgs_if_not_in_flow_list([msg], existing_flows)
        if msgs:
            chan = self._msg_hub.send(msgs, datapath)
            self._wait_for_responses(chan, len(msgs))

        return remaining_flows

    def _get_rule_match_flow_msgs(self, imsi, msisdn: bytes, uplink_tunnel: int, ip_addr, apn_ambr, rule):
        """
        Get flow msgs to get stats for a particular rule. Flows will match on
        IMSI, cookie (the rule num), in/out direction

        Args:
            imsi (string): subscriber to install rule for
            msisdn (bytes): subscriber ISDN
            ip_addr (string): subscriber session ipv4 address
            apn_ambr (integer): maximum bandwidth for non-GBR EPS bearers
            rule (PolicyRule): policy rule proto
        """
        rule_num = self._rule_mapper.get_or_create_rule_num(rule.id)
        priority = Utils.get_of_priority(rule.priority)

        flow_adds = []
        for flow in rule.flow_list:
            try:
                version = self._session_rule_version_mapper.get_version(imsi, ip_addr,
                                                                        rule.id)
                flow_adds.extend(self._get_classify_rule_flow_msgs(
                    imsi, msisdn, uplink_tunnel, ip_addr, apn_ambr, flow, rule_num, priority,
                    rule.qos, rule.hard_timeout, rule.id, rule.app_name,
                    rule.app_service_type, self.next_service_table,
                    version, self._qos_mgr, self._enforcement_stats_tbl))

            except FlowMatchError as err:  # invalid match
                self.logger.error(
                    "Failed to get flow msg '%s' for subscriber %s: %s",
                    rule.id, imsi, err)
                raise err
        return flow_adds

    @set_ev_cls(ofp_event.EventOFPMeterConfigStatsReply, MAIN_DISPATCHER)
    def meter_config_stats_reply_handler(self, ev):
        if not self._qos_mgr:
            return

        qos_impl = self._qos_mgr.impl
        if qos_impl and isinstance(qos_impl, MeterManager):
            qos_impl.handle_meter_config_stats(ev.msg.body)

    @set_ev_cls(ofp_event.EventOFPMeterFeaturesStatsReply, MAIN_DISPATCHER)
    def meter_features_stats_reply_handler(self, ev):
        if not self._qos_mgr:
            return

        qos_impl = self._qos_mgr.impl
        if qos_impl and isinstance(qos_impl, MeterManager):
            qos_impl.handle_meter_feature_stats(ev.msg.body)

    @set_ev_cls(ofp_event.EventOFPBarrierReply, MAIN_DISPATCHER)
    def _handle_barrier(self, ev):
        self._msg_hub.handle_barrier(ev)

    @set_ev_cls(ofp_event.EventOFPErrorMsg, MAIN_DISPATCHER)
    def _handle_error(self, ev):
        self._msg_hub.handle_error(ev)
Example #2
0
File: gy.py Project: go-magma/magma
class GYController(PolicyMixin, MagmaController):
    """
    GYController

    The GY controller installs flows for enforcement of GY final actions, this
    includes redirection and QoS(currently not supported)
    """

    APP_NAME = "gy"
    APP_TYPE = ControllerType.LOGICAL

    def __init__(self, *args, **kwargs):
        super(GYController, self).__init__(*args, **kwargs)
        self.tbl_num = self._service_manager.get_table_num(self.APP_NAME)
        self.next_main_table = self._service_manager.get_next_table_num(
            self.APP_NAME)
        self.loop = kwargs['loop']
        self._msg_hub = MessageHub(self.logger)
        self._internal_ip_allocator = kwargs['internal_ip_allocator']
        tbls = \
            self._service_manager.allocate_scratch_tables(self.APP_NAME, 2)
        self._redirect_scratch = tbls[0]
        self._mac_rewr = \
            self._service_manager.INTERNAL_MAC_IP_REWRITE_TBL_NUM
        self._bridge_ip_address = kwargs['config']['bridge_ip_address']
        self._clean_restart = kwargs['config']['clean_restart']
        self._redirect_manager = \
            RedirectionManager(
                self._bridge_ip_address,
                self.logger,
                self.tbl_num,
                self._service_manager.get_table_num(EGRESS),
                self._redirect_scratch,
                self._session_rule_version_mapper
            ).set_cwf_args(
                internal_ip_allocator=kwargs['internal_ip_allocator'],
                arp=kwargs['app_futures']['arpd'],
                mac_rewrite=self._mac_rewr,
                bridge_name=kwargs['config']['bridge_name'],
                egress_table=self._service_manager.get_table_num(EGRESS)
            )

    def initialize_on_connect(self, datapath):
        """
        Install the default flows on datapath connect event.

        Args:
            datapath: ryu datapath struct
        """
        self._datapath = datapath
        self._delete_all_flows(datapath)
        self._install_default_flows(datapath)

    def deactivate_rules(self, imsi, rule_ids):
        """
        Deactivate flows for a subscriber. If only imsi is present, delete all
        rule flows for a subscriber (i.e. end its session). If rule_ids are
        present, delete the rule flows for that subscriber.

        Args:
            imsi (string): subscriber id
            rule_ids (list of strings): policy rule ids
        """
        if not self.init_finished:
            self.logger.error('Pipelined is not initialized')
            return RuleModResult.FAILURE

        if self._datapath is None:
            self.logger.error('Datapath not initialized')
            return

        if not imsi:
            self.logger.error('No subscriber specified')
            return

        if not rule_ids:
            self._deactivate_flows_for_subscriber(imsi)
        else:
            for rule_id in rule_ids:
                self._deactivate_flow_for_rule(imsi, rule_id)

    def cleanup_state(self):
        pass

    def _deactivate_flows_for_subscriber(self, imsi):
        """ Deactivate all rules for a subscriber, ending any enforcement """
        match = MagmaMatch(imsi=encode_imsi(imsi))
        flows.delete_flow(self._datapath, self.tbl_num, match)
        self._redirect_manager.deactivate_flows_for_subscriber(
            self._datapath, imsi)

    def _deactivate_flow_for_rule(self, imsi, rule_id):
        """
        Deactivate a specific rule using the flow cookie for a subscriber
        """
        try:
            num = self._rule_mapper.get_rule_num(rule_id)
        except KeyError:
            self.logger.error('Could not find rule id %s', rule_id)
            return
        cookie, mask = (num, flows.OVS_COOKIE_MATCH_ALL)
        match = MagmaMatch(imsi=encode_imsi(imsi))
        flows.delete_flow(self._datapath,
                          self.tbl_num,
                          match,
                          cookie=cookie,
                          cookie_mask=mask)
        self._redirect_manager.deactivate_flow_for_rule(
            self._datapath, imsi, num)

    def _install_flow_for_rule(self, imsi, ip_addr, rule):
        if rule.redirect.support == rule.redirect.ENABLED:
            self._install_redirect_flow(imsi, ip_addr, rule)
            return RuleModResult.SUCCESS
        else:
            # TODO: Add support once sessiond implements restrict access QOS
            self.logger.error('GY only supports FINAL action redirect, other'
                              'final actions are not supported')
            return RuleModResult.FAILURE

    def _install_default_flow_for_subscriber(self, imsi):
        pass

    def _delete_all_flows(self, datapath):
        flows.delete_all_flows_from_table(datapath, self.tbl_num)
        flows.delete_all_flows_from_table(datapath, self._redirect_scratch)
        flows.delete_all_flows_from_table(datapath, self._mac_rewr)

    def _install_default_flows(self, datapath):
        """
        For each direction set the default flows to just forward to next app.
        The enforcement flows for each subscriber would be added when the
        IP session is created, by reaching out to the controller/PCRF.

        Args:
            datapath: ryu datapath struct
        """
        inbound_match = MagmaMatch(eth_type=ether_types.ETH_TYPE_IP,
                                   direction=Direction.IN)
        outbound_match = MagmaMatch(eth_type=ether_types.ETH_TYPE_IP,
                                    direction=Direction.OUT)
        flows.add_resubmit_next_service_flow(
            datapath,
            self.tbl_num,
            inbound_match, [],
            priority=flows.MINIMUM_PRIORITY,
            resubmit_table=self.next_main_table)
        flows.add_resubmit_next_service_flow(
            datapath,
            self.tbl_num,
            outbound_match, [],
            priority=flows.MINIMUM_PRIORITY,
            resubmit_table=self.next_main_table)

    def _install_redirect_flow(self, imsi, ip_addr, rule):
        rule_num = self._rule_mapper.get_or_create_rule_num(rule.id)
        priority = rule.priority
        # TODO currently if redirection is enabled we ignore other flows
        # from rule.flow_list, confirm that this is the expected behaviour
        redirect_request = RedirectionManager.RedirectRequest(
            imsi=imsi,
            ip_addr=ip_addr,
            rule=rule,
            rule_num=rule_num,
            priority=priority)
        try:
            self._redirect_manager.setup_cwf_redirect(self._datapath,
                                                      self.loop,
                                                      redirect_request)
            return RuleModResult.SUCCESS
        except RedirectException as err:
            self.logger.error(
                'Redirect Exception for imsi %s, rule.id - %s : %s', imsi,
                rule.id, err)
            return RuleModResult.FAILURE

    def _install_default_flows_if_not_installed(
            self, datapath,
            existing_flows: List[OFPFlowStats]) -> List[OFPFlowStats]:
        inbound_match = MagmaMatch(eth_type=ether_types.ETH_TYPE_IP,
                                   direction=Direction.IN)
        outbound_match = MagmaMatch(eth_type=ether_types.ETH_TYPE_IP,
                                    direction=Direction.OUT)

        inbound_msg = flows.get_add_resubmit_next_service_flow_msg(
            datapath,
            self.tbl_num,
            inbound_match, [],
            priority=flows.MINIMUM_PRIORITY,
            resubmit_table=self.next_main_table)

        outbound_msg = flows.get_add_resubmit_next_service_flow_msg(
            datapath,
            self.tbl_num,
            outbound_match, [],
            priority=flows.MINIMUM_PRIORITY,
            resubmit_table=self.next_main_table)

        msgs, remaining_flows = self._msg_hub \
            .filter_msgs_if_not_in_flow_list([inbound_msg, outbound_msg],
                                             existing_flows)
        if msgs:
            chan = self._msg_hub.send(msgs, datapath)
            self._wait_for_responses(chan, len(msgs))

        return remaining_flows

    @set_ev_cls(ofp_event.EventOFPBarrierReply, MAIN_DISPATCHER)
    def _handle_barrier(self, ev):
        self._msg_hub.handle_barrier(ev)

    @set_ev_cls(ofp_event.EventOFPErrorMsg, MAIN_DISPATCHER)
    def _handle_error(self, ev):
        self._msg_hub.handle_error(ev)