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)
class EnforcementController(PolicyMixin, MagmaController):
"""
EnforcementController
The enforcement controller installs flows for policy enforcement and
classification. Each flow installed matches on a rule and an IMSI and then
classifies the packet with the rule. The flow also redirects and drops
the packet as specified in the policy.
NOTE: Enforcement currently relies on the fact that policies do not
overlap. In this implementation, there is the idea of a 'default rule'
which is the catch-all. This rule is treated specially and tagged with a
specific priority.
"""
APP_NAME = "enforcement"
APP_TYPE = ControllerType.LOGICAL
ENFORCE_DROP_PRIORITY = flows.MINIMUM_PRIORITY + 1
# Should not overlap with the drop flow as drop matches all packets.
MIN_ENFORCE_PROGRAMMED_FLOW = ENFORCE_DROP_PRIORITY + 1
MAX_ENFORCE_PRIORITY = flows.MAXIMUM_PRIORITY
# Effectively range is 2 -> 65535
ENFORCE_PRIORITY_RANGE = MAX_ENFORCE_PRIORITY - MIN_ENFORCE_PROGRAMMED_FLOW
def __init__(self, *args, **kwargs):
super(EnforcementController, 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._enforcement_stats_scratch = self._service_manager.get_table_num(
EnforcementStatsController.APP_NAME)
self.loop = kwargs['loop']
self._relay_enabled = kwargs['mconfig'].relay_enabled
self._qos_map = QosQueueMap(kwargs['config']['nat_iface'],
kwargs['config']['enodeb_iface'],
kwargs['config']['enable_queue_pgm'])
self._msg_hub = MessageHub(self.logger)
self._redirect_scratch = \
self._service_manager.allocate_scratch_tables(self.APP_NAME, 1)[0]
self._bridge_ip_address = kwargs['config']['bridge_ip_address']
self._redirect_manager = None
self._clean_restart = kwargs['config']['clean_restart']
self._relay_enabled = kwargs['mconfig'].relay_enabled
if not self._relay_enabled:
self.logger.info('Relay mode is not enabled, enforcement will not'
' wait for sessiond to push flows.')
def initialize_on_connect(self, datapath):
"""
Install the default flows on datapath connect event.
Args:
datapath: ryu datapath struct
"""
self._datapath = datapath
if not self._relay_enabled:
self._install_default_flows_if_not_installed(datapath, [])
self._redirect_manager = RedirectionManager(
self._bridge_ip_address, self.logger, self.tbl_num,
self._enforcement_stats_scratch, self._redirect_scratch,
self._session_rule_version_mapper)
def cleanup_on_disconnect(self, datapath):
"""
Cleanup flows on datapath disconnect event.
Args:
datapath: ryu datapath struct
"""
if self._clean_restart:
self.delete_all_flows(datapath)
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)
@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)
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
"""
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
def get_of_priority(self, precedence):
"""
Lower the precedence higher the importance of the flow in 3GPP.
Higher the priority higher the importance of the flow in openflow.
Convert precedence to priority:
1 - Flows with precedence > 65534 will have min priority which is the
min priority for a programmed flow = (default drop + 1)
2 - Flows in the precedence range 0-65534 will have priority 65535 -
Precedence
:param precedence:
:return:
"""
if precedence >= self.ENFORCE_PRIORITY_RANGE:
self.logger.warning(
"Flow precedence is higher than OF range using min priority %d",
self.MIN_ENFORCE_PROGRAMMED_FLOW)
return self.MIN_ENFORCE_PROGRAMMED_FLOW
return self.MAX_ENFORCE_PRIORITY - precedence
def _get_rule_match_flow_msgs(self, imsi, rule):
"""
Get a flow msg 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
rule (PolicyRule): policy rule proto
"""
rule_num = self._rule_mapper.get_or_create_rule_num(rule.id)
priority = self.get_of_priority(rule.priority)
ul_qos = rule.qos.max_req_bw_ul
dl_qos = rule.qos.max_req_bw_dl
flow_adds = []
for flow in rule.flow_list:
try:
flow_adds.append(
self._get_classify_rule_flow_msg(imsi, flow, rule_num,
priority, ul_qos, dl_qos,
rule.hard_timeout,
rule.id))
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
def _install_flow_for_rule(self, imsi, ip_addr, 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
rule (PolicyRule): policy rule proto
"""
if rule.redirect.support == rule.redirect.ENABLED:
return self._install_redirect_flow(imsi, ip_addr, rule)
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, rule)
except FlowMatchError:
return RuleModResult.FAILURE
chan = self._msg_hub.send(flow_adds, self._datapath)
return self._wait_for_rule_responses(imsi, rule, chan)
def _wait_for_rule_responses(self, imsi, rule, chan):
def fail(err):
self.logger.error(
"Failed to install rule %s for subscriber %s: %s", rule.id,
imsi, err)
self._deactivate_flow_for_rule(imsi, rule.id)
return RuleModResult.FAILURE
for _ in range(len(rule.flow_list)):
try:
result = chan.get()
except MsgChannel.Timeout:
return fail("No response from OVS")
if not result.ok():
return fail(result.exception())
return RuleModResult.SUCCESS
def _get_classify_rule_flow_msg(self, imsi, flow, rule_num, priority,
ul_qos, dl_qos, hard_timeout, rule_id):
"""
Install a flow from a rule. If the flow action is DENY, then the flow
will drop the packet. Otherwise, the flow classifies the packet with
its matched rule and injects the rule num into the packet's register.
"""
flow_match = flow_match_to_magma_match(flow.match)
flow_match.imsi = encode_imsi(imsi)
flow_match_actions = self._get_classify_rule_of_actions(
flow, rule_num, imsi, ul_qos, dl_qos, rule_id)
if flow.action == flow.DENY:
return flows.get_add_drop_flow_msg(self._datapath,
self.tbl_num,
flow_match,
flow_match_actions,
hard_timeout=hard_timeout,
priority=priority,
cookie=rule_num)
if self._enforcement_stats_scratch:
return flows.get_add_resubmit_current_service_flow_msg(
self._datapath,
self.tbl_num,
flow_match,
flow_match_actions,
hard_timeout=hard_timeout,
priority=priority,
cookie=rule_num,
resubmit_table=self._enforcement_stats_scratch)
# If enforcement stats has not claimed a scratch table, resubmit
# directly to the next app.
return flows.get_add_resubmit_next_service_flow_msg(
self._datapath,
self.tbl_num,
flow_match,
flow_match_actions,
hard_timeout=hard_timeout,
priority=priority,
cookie=rule_num,
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 = self.get_of_priority(rule.priority)
redirect_request = RedirectionManager.RedirectRequest(
imsi=imsi,
ip_addr=ip_addr,
rule=rule,
rule_num=rule_num,
priority=priority)
try:
self._redirect_manager.handle_redirection(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 _get_classify_rule_of_actions(self, flow, rule_num, imsi, ul_qos,
dl_qos, rule_id):
parser = self._datapath.ofproto_parser
# encode the rule id in hex
of_note = parser.NXActionNote(list(rule_id.encode()))
actions = [of_note]
if flow.action == flow.DENY:
return actions
# QoS Rate-Limiting is currently supported for uplink traffic
qid = 0
if ul_qos != 0 and flow.match.direction == flow.match.UPLINK:
qid = self._qos_map.map_flow_to_queue(imsi, rule_num, ul_qos, True)
elif dl_qos != 0 and flow.match.direction == flow.match.DOWNLINK:
qid = self._qos_map.map_flow_to_queue(imsi, rule_num, dl_qos,
False)
if qid != 0:
actions.append(parser.OFPActionSetField(pkt_mark=qid))
version = self._session_rule_version_mapper.get_version(imsi, rule_id)
actions.extend([
parser.NXActionRegLoad2(dst='reg2', value=rule_num),
parser.NXActionRegLoad2(dst=RULE_VERSION_REG, value=version)
])
return actions
def _get_default_flow_msg_for_subscriber(self, imsi):
match = MagmaMatch(imsi=encode_imsi(imsi))
actions = []
return flows.get_add_drop_flow_msg(self._datapath,
self.tbl_num,
match,
actions,
priority=self.ENFORCE_DROP_PRIORITY)
def _install_default_flow_for_subscriber(self, imsi):
"""
Add a low priority flow to drop a subscriber's traffic in the event
that all rules have been deactivated.
Args:
imsi (string): subscriber id
"""
match = MagmaMatch(imsi=encode_imsi(imsi))
actions = [] # empty options == drop
flows.add_drop_flow(self._datapath,
self.tbl_num,
match,
actions,
priority=self.ENFORCE_DROP_PRIORITY)
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)
self._qos_map.del_queue_for_flow(imsi, num)
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)
self._qos_map.del_subscriber_queues(imsi)
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)
class EnforcementController(PolicyMixin, RestartMixin, MagmaController):
"""
EnforcementController
The enforcement controller installs flows for policy enforcement and
classification. Each flow installed matches on a rule and an IMSI and then
classifies the packet with the rule. The flow also redirects and drops
the packet as specified in the policy.
NOTE: Enforcement currently relies on the fact that policies do not
overlap. In this implementation, there is the idea of a 'default rule'
which is the catch-all. This rule is treated specially and tagged with a
specific priority.
"""
APP_NAME = "enforcement"
APP_TYPE = ControllerType.LOGICAL
DEFAULT_FLOW_COOKIE = 0xfffffffffffffffe
def __init__(self, *args, **kwargs):
super(EnforcementController, 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(
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._redirect_scratch = \
self._service_manager.allocate_scratch_tables(self.APP_NAME, 1)[0]
self._bridge_ip_address = kwargs['config']['bridge_ip_address']
self._redirect_manager = None
self._qos_mgr = None
self._clean_restart = kwargs['config']['clean_restart']
self._redirect_manager = RedirectionManager(
self._bridge_ip_address, self.logger, self.tbl_num,
self._enforcement_stats_tbl, self.next_main_table,
self._redirect_scratch, self._session_rule_version_mapper)
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.get_qos_manager(datapath, self.loop,
self._config)
def cleanup_on_disconnect(self, datapath):
"""
Cleanup flows on datapath disconnect event.
Args:
datapath: ryu datapath struct
"""
if self._clean_restart:
self.delete_all_flows(datapath)
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)
def cleanup_state(self):
pass
@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)
@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)
def _get_default_flow_msgs(self, datapath) -> DefaultMsgsMap:
"""
Gets the default flow msg that forward to stats table(traffic will be
dropped because stats table doesn't forward anything)
Args:
datapath: ryu datapath struct
Returns:
The list of default msgs to add
"""
match = MagmaMatch()
msg = flows.get_add_resubmit_next_service_flow_msg(
datapath,
self.tbl_num,
match, [],
priority=flows.MINIMUM_PRIORITY,
resubmit_table=self._enforcement_stats_tbl,
cookie=self.DEFAULT_FLOW_COOKIE)
return {self.tbl_num: [msg]}
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 MSISDN
uplink_tunnel (int): tunnel ID of the subscriber.
ip_addr (string): subscriber session ipv4 address
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_main_table, version, self._qos_mgr,
self._enforcement_stats_tbl, rule.he.urls))
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
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
msisdn (bytes): subscriber MSISDN
uplink_tunnel (int): tunnel ID of the subscriber.
ip_addr (string): subscriber session ipv4 address
rule (PolicyRule): policy rule proto
"""
if rule.redirect.support == rule.redirect.ENABLED:
return self._install_redirect_flow(imsi, ip_addr, rule)
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
try:
chan = self._msg_hub.send(flow_adds, self._datapath)
except MagmaDPDisconnectedError:
self.logger.error(
"Datapath disconnected, failed to install rule %s"
"for imsi %s", rule, imsi)
return RuleModResult.FAILURE
return self._wait_for_rule_responses(imsi, ip_addr, rule, chan)
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 = Utils.get_of_priority(rule.priority)
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:
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 _get_default_flow_msgs_for_subscriber(self, *_):
pass
def _install_default_flow_for_subscriber(self, *_):
pass
def _deactivate_flow_for_rule(self, imsi, ip_addr, 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
if num is None:
self.logger.error('Rule num is None for rule %s', rule_id)
return
cookie, mask = (num, flows.OVS_COOKIE_MATCH_ALL)
ip_match_in = get_ue_ip_match_args(ip_addr, Direction.IN)
match = MagmaMatch(eth_type=get_eth_type(ip_addr),
imsi=encode_imsi(imsi),
**ip_match_in)
flows.delete_flow(self._datapath,
self.tbl_num,
match,
cookie=cookie,
cookie_mask=mask)
ip_match_out = get_ue_ip_match_args(ip_addr, Direction.OUT)
match = MagmaMatch(eth_type=get_eth_type(ip_addr),
imsi=encode_imsi(imsi),
**ip_match_out)
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, num)
def _deactivate_flows_for_subscriber(self, imsi, ip_addr):
""" Deactivate all rules for specified subscriber session """
ip_match_in = get_ue_ip_match_args(ip_addr, Direction.IN)
match = MagmaMatch(eth_type=get_eth_type(ip_addr),
imsi=encode_imsi(imsi),
**ip_match_in)
flows.delete_flow(self._datapath, self.tbl_num, match)
ip_match_out = get_ue_ip_match_args(ip_addr, Direction.OUT)
match = MagmaMatch(eth_type=get_eth_type(ip_addr),
imsi=encode_imsi(imsi),
**ip_match_out)
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)
def deactivate_rules(self, imsi, ip_addr, rule_ids):
"""
Deactivate flows for a subscriber.
Only imsi -> remove all rules for imsi
imsi+ipv4 -> remove all rules for imsi session
imsi+rule_ids -> remove specific rules for imsi (for all sessions)
imsi+ipv4+rule_ids -> remove rules for specific imsi session
Args:
imsi (string): subscriber id
ip_addr (string): subscriber ip address
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 recover_state(self, _):
pass
class EnforcementController(PolicyMixin, MagmaController):
"""
EnforcementController
The enforcement controller installs flows for policy enforcement and
classification. Each flow installed matches on a rule and an IMSI and then
classifies the packet with the rule. The flow also redirects and drops
the packet as specified in the policy.
NOTE: Enforcement currently relies on the fact that policies do not
overlap. In this implementation, there is the idea of a 'default rule'
which is the catch-all. This rule is treated specially and tagged with a
specific priority.
"""
APP_NAME = "enforcement"
APP_TYPE = ControllerType.LOGICAL
ENFORCE_DROP_PRIORITY = flows.MINIMUM_PRIORITY + 1
# For allowing unlcassified flows for app/service type rules.
UNCLASSIFIED_ALLOW_PRIORITY = ENFORCE_DROP_PRIORITY + 1
# Should not overlap with the drop flow as drop matches all packets.
MIN_ENFORCE_PROGRAMMED_FLOW = UNCLASSIFIED_ALLOW_PRIORITY + 1
MAX_ENFORCE_PRIORITY = flows.MAXIMUM_PRIORITY
# Effectively range is 3 -> 65535
ENFORCE_PRIORITY_RANGE = MAX_ENFORCE_PRIORITY - MIN_ENFORCE_PROGRAMMED_FLOW
def __init__(self, *args, **kwargs):
super(EnforcementController, 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._enforcement_stats_scratch = self._service_manager.get_table_num(
EnforcementStatsController.APP_NAME)
self.loop = kwargs['loop']
self._msg_hub = MessageHub(self.logger)
self._redirect_scratch = \
self._service_manager.allocate_scratch_tables(self.APP_NAME, 1)[0]
self._bridge_ip_address = kwargs['config']['bridge_ip_address']
self._redirect_manager = None
self._qos_mgr = None
self._clean_restart = kwargs['config']['clean_restart']
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._redirect_manager = RedirectionManager(
self._bridge_ip_address,
self.logger,
self.tbl_num,
self._enforcement_stats_scratch,
self._redirect_scratch,
self._session_rule_version_mapper)
def cleanup_on_disconnect(self, datapath):
"""
Cleanup flows on datapath disconnect event.
Args:
datapath: ryu datapath struct
"""
if self._clean_restart:
self.delete_all_flows(datapath)
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)
def cleanup_state(self):
pass
@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)
@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)
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
"""
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
def get_of_priority(self, precedence):
"""
Lower the precedence higher the importance of the flow in 3GPP.
Higher the priority higher the importance of the flow in openflow.
Convert precedence to priority:
1 - Flows with precedence > 65534 will have min priority which is the
min priority for a programmed flow = (default drop + 1)
2 - Flows in the precedence range 0-65534 will have priority 65535 -
Precedence
:param precedence:
:return:
"""
if precedence >= self.ENFORCE_PRIORITY_RANGE:
self.logger.warning(
"Flow precedence is higher than OF range using min priority %d",
self.MIN_ENFORCE_PROGRAMMED_FLOW)
return self.MIN_ENFORCE_PROGRAMMED_FLOW
return self.MAX_ENFORCE_PRIORITY - precedence
def _get_rule_match_flow_msgs(self, imsi, 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
ip_addr (string): subscriber session ipv4 address
rule (PolicyRule): policy rule proto
"""
rule_num = self._rule_mapper.get_or_create_rule_num(rule.id)
priority = self.get_of_priority(rule.priority)
flow_adds = []
for flow in rule.flow_list:
try:
flow_adds.extend(self._get_classify_rule_flow_msgs(
imsi, ip_addr, apn_ambr, flow, rule_num, priority,
rule.qos, rule.hard_timeout, rule.id, rule.app_name,
rule.app_service_type))
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
def _install_flow_for_rule(self, imsi, 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
rule (PolicyRule): policy rule proto
"""
if rule.redirect.support == rule.redirect.ENABLED:
return self._install_redirect_flow(imsi, ip_addr, rule)
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, 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, rule, chan)
def _wait_for_rule_responses(self, imsi, rule, chan):
def fail(err):
self.logger.error(
"Failed to install rule %s for subscriber %s: %s",
rule.id, imsi, err)
self._deactivate_flow_for_rule(imsi, rule.id)
return RuleModResult.FAILURE
for _ in range(len(rule.flow_list)):
try:
result = chan.get()
except MsgChannel.Timeout:
return fail("No response from OVS")
if not result.ok():
return fail(result.exception())
return RuleModResult.SUCCESS
def _get_classify_rule_flow_msgs(self, imsi, ip_addr, apn_ambr, flow, rule_num,
priority, qos, hard_timeout, rule_id,
app_name, app_service_type):
"""
Install a flow from a rule. If the flow action is DENY, then the flow
will drop the packet. Otherwise, the flow classifies the packet with
its matched rule and injects the rule num into the packet's register.
"""
flow_match = flow_match_to_magma_match(flow.match)
flow_match.imsi = encode_imsi(imsi)
flow_match_actions, instructions = self._get_classify_rule_of_actions(
flow, rule_num, imsi, ip_addr, apn_ambr, qos, rule_id)
msgs = []
if app_name:
# We have to allow initial traffic to pass through, before it gets
# classified by DPI, flow match set app_id to unclassified
flow_match.app_id = UNCLASSIFIED_PROTO_ID
# Set
parser = self._datapath.ofproto_parser
passthrough_actions = flow_match_actions + \
[parser.NXActionRegLoad2(dst=SCRATCH_REGS[1],
value=IGNORE_STATS)]
msgs.append(
flows.get_add_resubmit_current_service_flow_msg(
self._datapath,
self.tbl_num,
flow_match,
passthrough_actions,
hard_timeout=hard_timeout,
priority=self.UNCLASSIFIED_ALLOW_PRIORITY,
cookie=rule_num,
resubmit_table=self._enforcement_stats_scratch
)
)
flow_match.app_id = get_app_id(
PolicyRule.AppName.Name(app_name),
PolicyRule.AppServiceType.Name(app_service_type),
)
if flow.action == flow.DENY:
msgs.append(flows.get_add_drop_flow_msg(
self._datapath,
self.tbl_num,
flow_match,
flow_match_actions,
hard_timeout=hard_timeout,
priority=priority,
cookie=rule_num)
)
else:
msgs.append(flows.get_add_resubmit_current_service_flow_msg(
self._datapath,
self.tbl_num,
flow_match,
flow_match_actions,
instructions=instructions,
hard_timeout=hard_timeout,
priority=priority,
cookie=rule_num,
resubmit_table=self._enforcement_stats_scratch)
)
return msgs
def _install_redirect_flow(self, imsi, ip_addr, rule):
rule_num = self._rule_mapper.get_or_create_rule_num(rule.id)
priority = self.get_of_priority(rule.priority)
redirect_request = RedirectionManager.RedirectRequest(
imsi=imsi,
ip_addr=ip_addr,
rule=rule,
rule_num=rule_num,
priority=priority)
try:
self._redirect_manager.handle_redirection(
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 _get_classify_rule_of_actions(self, flow, rule_num, imsi, ip_addr,
apn_ambr, qos, rule_id):
parser = self._datapath.ofproto_parser
instructions = []
# encode the rule id in hex
of_note = parser.NXActionNote(list(rule_id.encode()))
actions = [of_note]
if flow.action == flow.DENY:
return actions, instructions
mbr_ul = qos.max_req_bw_ul
mbr_dl = qos.max_req_bw_dl
qos_info = None
ambr = None
d = flow.match.direction
if d == flow.match.UPLINK:
if apn_ambr:
ambr = apn_ambr.max_bandwidth_ul
if mbr_ul != 0:
qos_info = QosInfo(gbr=qos.gbr_ul, mbr=mbr_ul)
if d == flow.match.DOWNLINK:
if apn_ambr:
ambr = apn_ambr.max_bandwidth_dl
if mbr_dl != 0:
qos_info = QosInfo(gbr=qos.gbr_dl, mbr=mbr_dl)
if qos_info or ambr:
action, inst = self._qos_mgr.add_subscriber_qos(
imsi, ip_addr, ambr, rule_num, d, qos_info)
self.logger.debug("adding Actions %s instruction %s ", action, inst)
if action:
actions.append(action)
if inst:
instructions.append(inst)
version = self._session_rule_version_mapper.get_version(imsi, rule_id)
actions.extend(
[parser.NXActionRegLoad2(dst='reg2', value=rule_num),
parser.NXActionRegLoad2(dst=RULE_VERSION_REG, value=version)
])
return actions, instructions
def _get_default_flow_msg_for_subscriber(self, imsi):
match = MagmaMatch(imsi=encode_imsi(imsi))
actions = []
return flows.get_add_drop_flow_msg(self._datapath, self.tbl_num,
match, actions, priority=self.ENFORCE_DROP_PRIORITY)
def _install_default_flow_for_subscriber(self, imsi):
"""
Add a low priority flow to drop a subscriber's traffic in the event
that all rules have been deactivated.
Args:
imsi (string): subscriber id
"""
match = MagmaMatch(imsi=encode_imsi(imsi))
actions = [] # empty options == drop
flows.add_drop_flow(self._datapath, self.tbl_num, match, actions,
priority=self.ENFORCE_DROP_PRIORITY)
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)
self._qos_mgr.remove_subscriber_qos(imsi, num)
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)
self._qos_mgr.remove_subscriber_qos(imsi)
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)
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)
class EnforcementController(MagmaController):
"""
EnforcementController
The enforcement controller installs flows for tracking subscriber usage
per rule and enforcing the usage. Each flow installed matches on a rule
and an IMSI and then the statistics are sent to sessiond for tracking.
NOTE: Enforcement currently relies on the fact that policies do not
overlap. In this implementation, there is the idea of a 'default rule'
which is the catch-all. This rule is treated specially and tagged with a
specific priority.
"""
APP_NAME = "enforcement"
ENFORCE_DROP_PRIORITY = flows.MINIMUM_PRIORITY + 1
# Should not overlap with the drop flow as drop matches all packets.
MIN_ENFORCE_PROGRAMMED_FLOW = ENFORCE_DROP_PRIORITY + 1
MAX_ENFORCE_PRIORITY = flows.MAXIMUM_PRIORITY
# Effectively range is 2 -> 65535
ENFORCE_PRIORITY_RANGE = MAX_ENFORCE_PRIORITY - MIN_ENFORCE_PROGRAMMED_FLOW
def __init__(self, *args, **kwargs):
super(EnforcementController, self).__init__(*args, **kwargs)
self.tbl_num = self._service_manager.get_table_num(self.APP_NAME)
self.next_table = self._service_manager.get_next_table_num(
self.APP_NAME)
self._datapath = None
self._rule_mapper = kwargs['rule_id_mapper']
self.loop = kwargs['loop']
self._policy_dict = PolicyRuleDict()
self._qos_map = QosQueueMap(kwargs['config']['nat_iface'],
kwargs['config']['enodeb_iface'],
kwargs['config']['enable_queue_pgm'])
self._msg_hub = MessageHub(self.logger)
self._redirect_manager = RedirectionManager(
kwargs['config']['bridge_ip_address'], self.logger, self.tbl_num,
self.next_table)
def initialize_on_connect(self, datapath):
"""
Install the default flows on datapath connect event.
Args:
datapath: ryu datapath struct
"""
flows.delete_all_flows_from_table(datapath, self.tbl_num)
self._install_default_flows(datapath)
self._datapath = datapath
def cleanup_on_disconnect(self, datapath):
"""
Cleanup flows on datapath disconnect event.
Args:
datapath: ryu datapath struct
"""
flows.delete_all_flows_from_table(datapath, self.tbl_num)
@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)
def _install_default_flows(self, datapath):
"""
For each direction set the default flows to just forward to next table.
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_flow(datapath,
self.tbl_num,
inbound_match, [],
priority=flows.MINIMUM_PRIORITY,
resubmit_table=self.next_table)
flows.add_flow(datapath,
self.tbl_num,
outbound_match, [],
priority=flows.MINIMUM_PRIORITY,
resubmit_table=self.next_table)
def _install_flow_for_static_rule(self, imsi, ip_addr, rule_id):
"""
Install a flow to get stats for a particular static rule id. The rule
will be loaded from Redis and installed
Args:
imsi (string): subscriber to install rule for
ip_addr (string): subscriber session ipv4 address
rule_id (string): policy rule id
"""
rule = self._policy_dict[rule_id]
if rule is None:
self.logger.error("Could not find rule for rule_id: %s", rule_id)
return RuleModResult.FAILURE
return self._install_flow_for_rule(imsi, ip_addr, rule)
def get_of_priority(self, precedence):
"""
Lower the precedence higher the importance of the flow in 3GPP.
Higher the priority higher the importance of the flow in openflow.
Convert precedence to priority:
1 - Flows with precedence > 65534 will have min priority which is the
min priority for a programmed flow = (default drop + 1)
2 - Flows in the precedence range 0-65534 will have priority 65535 -
Precedence
:param precedence:
:return:
"""
if precedence >= self.ENFORCE_PRIORITY_RANGE:
self.logger.warning(
"Flow precedence is higher than OF range using "
"min priority %d", self.MIN_ENFORCE_PROGRAMMED_FLOW)
return self.MIN_ENFORCE_PROGRAMMED_FLOW
return self.MAX_ENFORCE_PRIORITY - precedence
def _install_flow_for_rule(self, imsi, ip_addr, 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
rule (PolicyRule): policy rule proto
"""
rule_num = self._rule_mapper.get_or_create_rule_num(rule.id)
priority = self.get_of_priority(rule.priority)
ul_qos = rule.qos.max_req_bw_ul
if rule.redirect.support == rule.redirect.ENABLED:
# 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.handle_redirection(
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
flow_adds = []
for flow in rule.flow_list:
try:
flow_adds.append(
self._get_add_flow_msg(imsi, flow, rule_num, priority,
ul_qos, rule.hard_timeout, rule.id))
except FlowMatchError as err: # invalid match
self.logger.error(
"Failed to install rule %s for subscriber %s: %s", rule.id,
imsi, err)
return RuleModResult.FAILURE
chan = self._msg_hub.send(flow_adds, self._datapath)
return self._wait_for_responses(imsi, rule, chan)
def _wait_for_responses(self, imsi, rule, chan):
def fail(err):
self.logger.error(
"Failed to install rule %s for subscriber %s: %s", rule.id,
imsi, err)
self._deactivate_flow_for_rule(imsi, rule.id)
return RuleModResult.FAILURE
for _ in range(len(rule.flow_list)):
try:
result = chan.get()
except MsgChannel.Timeout:
return fail("No response from OVS")
if not result.ok():
return fail(result.exception())
return RuleModResult.SUCCESS
def _get_add_flow_msg(self, imsi, flow, rule_num, priority, ul_qos,
hard_timeout, rule_id):
match = flow.match
ryu_match = flow_match_to_magma_match(match)
ryu_match.imsi = encode_imsi(imsi)
actions = self._get_of_actions_for_flow(flow, rule_num, imsi, ul_qos,
rule_id)
resubmit_table = self.next_table if flow.action != flow.DENY else None
return flows.get_add_flow_msg(self._datapath,
self.tbl_num,
ryu_match,
actions,
hard_timeout=hard_timeout,
priority=priority,
cookie=rule_num,
resubmit_table=resubmit_table)
def _get_of_actions_for_flow(self, flow, rule_num, imsi, ul_qos, rule_id):
parser = self._datapath.ofproto_parser
# encode the rule id in hex
of_note = parser.NXActionNote(list(rule_id.encode()))
if flow.action == flow.DENY:
return [of_note]
# QoS Rate-Limiting is currently supported for uplink traffic
if ul_qos != 0 and flow.match.direction == flow.match.UPLINK:
qid = self._qos_map.map_flow_to_queue(imsi, rule_num, ul_qos, True)
if qid != 0:
return [
parser.OFPActionSetField(pkt_mark=qid),
parser.NXActionRegLoad2(dst='reg2', value=rule_num),
of_note
]
return [parser.NXActionRegLoad2(dst='reg2', value=rule_num), of_note]
def _install_drop_flow(self, imsi):
"""
Add a low priority flow to drop a subscriber's traffic in the event
that all rules have been deactivated.
Args:
imsi (string): subscriber id
"""
match = MagmaMatch(imsi=encode_imsi(imsi))
actions = [] # empty options == drop
flows.add_flow(self._datapath,
self.tbl_num,
match,
actions,
priority=self.ENFORCE_DROP_PRIORITY)
def activate_flows(self, imsi, ip_addr, static_rule_ids, dynamic_rules,
fut):
"""
Activate the flows for a subscriber based on the rules stored in Redis.
During activation, another low priority flow is installed for the
subscriber in the event that all rules are out of credit.
Args:
imsi (string): subscriber id
ip_addr (string): subscriber session ipv4 address
static_rule_ids (string []): list of static rules to activate
dynamic_rules (PolicyRule []): list of dynamic rules to activate
fut (Future): future to wait on the results of flow activations
"""
if self._datapath is None:
self.logger.error('Datapath not initialized for adding flows')
fut.set_result(
ActivateFlowsResult(
static_rule_results=[
RuleModResult(
rule_id=rule_id,
result=RuleModResult.FAILURE,
) for rule_id in static_rule_ids
],
dynamic_rule_results=[
RuleModResult(
rule_id=rule.id,
result=RuleModResult.FAILURE,
) for rule in dynamic_rules
],
))
return
static_results = []
for rule_id in static_rule_ids:
res = self._install_flow_for_static_rule(imsi, ip_addr, rule_id)
static_results.append(RuleModResult(rule_id=rule_id, result=res))
dyn_results = []
for rule in dynamic_rules:
res = self._install_flow_for_rule(imsi, ip_addr, rule)
dyn_results.append(RuleModResult(rule_id=rule.id, result=res))
# No matter what, install base flow to drop packets when all other
# flows have been deactivated
self._install_drop_flow(imsi)
fut.set_result(
ActivateFlowsResult(
static_rule_results=static_results,
dynamic_rule_results=dyn_results,
))
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)
self._qos_map.del_queue_for_flow(imsi, num)
def _deactivate_flows_for_subscriber(self, imsi):
""" Deactivate all rules for a subscriber, ending any enforcement """
flows.delete_flow(self._datapath, self.tbl_num,
MagmaMatch(imsi=encode_imsi(imsi)))
self._redirect_manager.deactivate_flows_for_subscriber(
self._datapath, imsi)
self._qos_map.del_subscriber_queues(imsi)
def deactivate_flows(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 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)
class EnforcementController(PolicyMixin, MagmaController):
"""
EnforcementController
The enforcement controller installs flows for policy enforcement and
classification. Each flow installed matches on a rule and an IMSI and then
classifies the packet with the rule. The flow also redirects and drops
the packet as specified in the policy.
NOTE: Enforcement currently relies on the fact that policies do not
overlap. In this implementation, there is the idea of a 'default rule'
which is the catch-all. This rule is treated specially and tagged with a
specific priority.
"""
APP_NAME = "enforcement"
APP_TYPE = ControllerType.LOGICAL
def __init__(self, *args, **kwargs):
super(EnforcementController, 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._enforcement_stats_tbl = self._service_manager.get_table_num(
EnforcementStatsController.APP_NAME)
self.loop = kwargs['loop']
self._msg_hub = MessageHub(self.logger)
self._redirect_scratch = \
self._service_manager.allocate_scratch_tables(self.APP_NAME, 1)[0]
self._bridge_ip_address = kwargs['config']['bridge_ip_address']
self._redirect_manager = None
self._qos_mgr = None
self._clean_restart = kwargs['config']['clean_restart']
self._redirect_manager = RedirectionManager(
self._bridge_ip_address,
self.logger,
self.tbl_num,
self._enforcement_stats_tbl,
self._redirect_scratch,
self._session_rule_version_mapper)
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()
def cleanup_on_disconnect(self, datapath):
"""
Cleanup flows on datapath disconnect event.
Args:
datapath: ryu datapath struct
"""
if self._clean_restart:
self.delete_all_flows(datapath)
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)
def cleanup_state(self):
pass
@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)
@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)
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
"""
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
def _get_rule_match_flow_msgs(self, imsi, 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
ip_addr (string): subscriber session ipv4 address
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, ip_addr, apn_ambr, flow, rule_num, priority,
rule.qos, rule.hard_timeout, rule.id, rule.app_name,
rule.app_service_type, self._enforcement_stats_tbl,
version, self._qos_mgr))
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
def _install_flow_for_rule(self, imsi, 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
rule (PolicyRule): policy rule proto
"""
if rule.redirect.support == rule.redirect.ENABLED:
return self._install_redirect_flow(imsi, ip_addr, rule)
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, 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, rule, chan)
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 = Utils.get_of_priority(rule.priority)
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:
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 _get_default_flow_msgs_for_subscriber(self, imsi, ip_addr):
ip_match_in = get_ue_ip_match_args(ip_addr, Direction.IN)
match_in = MagmaMatch(eth_type=get_eth_type(ip_addr),
imsi=encode_imsi(imsi), **ip_match_in)
ip_match_out = get_ue_ip_match_args(ip_addr, Direction.OUT)
match_out = MagmaMatch(eth_type=get_eth_type(ip_addr),
imsi=encode_imsi(imsi), **ip_match_out)
actions = []
return [
flows.get_add_drop_flow_msg(
self._datapath, self.tbl_num, match_in, actions,
priority=Utils.DROP_PRIORITY),
flows.get_add_drop_flow_msg(
self._datapath, self.tbl_num, match_out, actions,
priority=Utils.DROP_PRIORITY)]
def _install_default_flow_for_subscriber(self, imsi, ip_addr):
"""
Add a low priority flow to drop a subscriber's traffic in the event
that all rules have been deactivated.
Args:
imsi (string): subscriber id
"""
msgs = self._get_default_flow_msgs_for_subscriber(imsi, ip_addr)
if msgs:
chan = self._msg_hub.send(msgs, self._datapath)
self._wait_for_responses(chan, len(msgs))
def _deactivate_flow_for_rule(self, imsi, ip_addr, 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)
ip_match_in = get_ue_ip_match_args(ip_addr, Direction.IN)
match = MagmaMatch(eth_type=get_eth_type(ip_addr),
imsi=encode_imsi(imsi), **ip_match_in)
flows.delete_flow(self._datapath, self.tbl_num, match,
cookie=cookie, cookie_mask=mask)
ip_match_out = get_ue_ip_match_args(ip_addr, Direction.OUT)
match = MagmaMatch(eth_type=get_eth_type(ip_addr),
imsi=encode_imsi(imsi), **ip_match_out)
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)
def _deactivate_flows_for_subscriber(self, imsi, ip_addr):
""" Deactivate all rules for specified subscriber session """
ip_match_in = get_ue_ip_match_args(ip_addr, Direction.IN)
match = MagmaMatch(eth_type=get_eth_type(ip_addr),
imsi=encode_imsi(imsi), **ip_match_in)
flows.delete_flow(self._datapath, self.tbl_num, match)
ip_match_out = get_ue_ip_match_args(ip_addr, Direction.OUT)
match = MagmaMatch(eth_type=get_eth_type(ip_addr),
imsi=encode_imsi(imsi), **ip_match_out)
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)
def deactivate_rules(self, imsi, ip_addr, rule_ids):
"""
Deactivate flows for a subscriber.
Only imsi -> remove all rules for imsi
imsi+ipv4 -> remove all rules for imsi session
imsi+rule_ids -> remove specific rules for imsi (for all sessions)
imsi+ipv4+rule_ids -> remove rules for specific imsi session
Args:
imsi (string): subscriber id
ip_addr (string): subscriber ip address
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)
