"""Manage flooding/learning on standalone datapaths."""
# Copyright (C) 2013 Nippon Telegraph and Telephone Corporation.
# Copyright (C) 2015 Brad Cowie, Christopher Lorier and Joe Stringer.
# Copyright (C) 2015 Research and Education Advanced Network New Zealand Ltd.
# Copyright (C) 2015--2019 The Contributors
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import copy
import functools
from faucet import valve_of
from faucet import valve_packet
from faucet.valve_manager_base import ValveManagerBase
from faucet.vlan import NullVLAN
[docs]class ValveSwitchManager(ValveManagerBase):
"""Implement dataplane based flooding/learning for standalone dataplanes."""
# Enumerate possible eth_dst flood destinations.
# First bool says whether to flood this destination if the VLAN
# has unicast flooding enabled (if unicast flooding is enabled,
# then we flood all destination eth_dsts).
FLOOD_DSTS = (
(True, None, None, None),
(False, None, valve_packet.BRIDGE_GROUP_ADDRESS, valve_packet.mac_byte_mask(3)), # 802.x
(False, None, '01:00:5E:00:00:00', valve_packet.mac_byte_mask(3)), # IPv4 multicast
(False, None, '33:33:00:00:00:00', valve_packet.mac_byte_mask(2)), # IPv6 multicast
(False, None, valve_of.mac.BROADCAST_STR, valve_packet.mac_byte_mask(6)), # eth broadcasts
)
# Ports with restricted broadcast enabled may only receive these broadcasts.
RESTRICTED_FLOOD_DISTS = (
(False, valve_of.ether.ETH_TYPE_ARP,
valve_of.mac.BROADCAST_STR, valve_packet.mac_byte_mask(6)), # ARP
(False, valve_of.ether.ETH_TYPE_IPV6,
'33:33:FF:00:00:00', valve_packet.mac_byte_mask(3)), # IPv6 multicast for ND
(False, valve_of.ether.ETH_TYPE_IPV6,
valve_packet.IPV6_ALL_ROUTERS_MCAST, valve_packet.mac_byte_mask(6)), # IPV6 all routers
(False, valve_of.ether.ETH_TYPE_IPV6,
valve_packet.IPV6_ALL_NODES_MCAST, valve_packet.mac_byte_mask(6)), # IPv6 all nodes
)
def __init__(self, logger, ports, vlans, # pylint: disable=too-many-arguments
vlan_table, vlan_acl_table, eth_src_table, eth_dst_table,
eth_dst_hairpin_table, flood_table, classification_table,
pipeline, use_group_table, groups, combinatorial_port_flood,
canonical_port_order, restricted_bcast_arpnd, has_externals,
learn_ban_timeout, learn_timeout, learn_jitter, cache_update_guard_time, idle_dst):
self.logger = logger
self.ports = ports
self.vlans = vlans
self.vlan_table = vlan_table
self.vlan_acl_table = vlan_acl_table
self.eth_src_table = eth_src_table
self.eth_dst_table = eth_dst_table
self.eth_dst_hairpin_table = eth_dst_hairpin_table
self.flood_table = flood_table
self.classification_table = classification_table
self.pipeline = pipeline
self.use_group_table = use_group_table
self.groups = groups
self.combinatorial_port_flood = combinatorial_port_flood
self.canonical_port_order = canonical_port_order
self.restricted_bcast_arpnd = restricted_bcast_arpnd
self.has_externals = has_externals
self.learn_ban_timeout = learn_ban_timeout
self.learn_timeout = learn_timeout
self.learn_jitter = learn_jitter
self.cache_update_guard_time = cache_update_guard_time
self.idle_dst = idle_dst
self.output_table = self.eth_dst_table
if self.eth_dst_hairpin_table:
self.output_table = self.eth_dst_hairpin_table
if restricted_bcast_arpnd:
self.flood_dsts = self.FLOOD_DSTS + self.RESTRICTED_FLOOD_DISTS
else:
self.flood_dsts = self.FLOOD_DSTS
self.bypass_priority = self._FILTER_PRIORITY
self.host_priority = self._MATCH_PRIORITY
self.flood_priority = self._MATCH_PRIORITY
self.low_priority = self._LOW_PRIORITY
self.high_priority = self._HIGH_PRIORITY
self.classification_offset = 0x100
[docs] def initialise_tables(self):
"""Initialise the flood table with filtering flows."""
ofmsgs = []
for eth_dst, eth_dst_mask in (
(valve_packet.CISCO_CDP_VTP_UDLD_ADDRESS, valve_packet.mac_byte_mask(6)),
(valve_packet.CISCO_SPANNING_GROUP_ADDRESS, valve_packet.mac_byte_mask(6)),
(valve_packet.BRIDGE_GROUP_ADDRESS, valve_packet.BRIDGE_GROUP_MASK)):
ofmsgs.append(self.flood_table.flowdrop(
self.flood_table.match(eth_dst=eth_dst, eth_dst_mask=eth_dst_mask),
priority=self._mask_flood_priority(eth_dst_mask)))
return ofmsgs
[docs] def floods_to_root(self, _dp_obj):
"""Return True if the given dp floods (only) to root switch"""
return False
@functools.lru_cache(maxsize=1024)
def _mask_flood_priority(self, eth_dst_mask):
return self.flood_priority + valve_packet.mac_mask_bits(eth_dst_mask)
@staticmethod
def _vlan_all_ports(vlan, exclude_unicast):
"""Return list of all ports that should be flooded to on a VLAN."""
return list(vlan.flood_ports(vlan.get_ports(), exclude_unicast))
def _build_flood_local_rule_actions(self, vlan, exclude_unicast, in_port, # pylint: disable=too-many-arguments
exclude_all_external, exclude_restricted_bcast_arpnd):
"""Return a list of flood actions to flood packets from a port."""
external_ports = self.canonical_port_order(vlan.loop_protect_external_ports_up())
exclude_ports = vlan.excluded_lag_ports(in_port)
exclude_ports.update(vlan.exclude_native_if_dot1x())
if exclude_all_external or (in_port is not None and in_port.loop_protect_external):
exclude_ports.update(set(external_ports))
else:
exclude_ports.update(set(external_ports[1:]))
if exclude_restricted_bcast_arpnd:
exclude_ports.update(set(vlan.restricted_bcast_arpnd_ports()))
return valve_of.flood_port_outputs(
vlan.tagged_flood_ports(exclude_unicast),
vlan.untagged_flood_ports(exclude_unicast),
in_port=in_port,
exclude_ports=exclude_ports)
def _build_flood_rule_actions(self, vlan, exclude_unicast, in_port, # pylint: disable=too-many-arguments
exclude_all_external=False, exclude_restricted_bcast_arpnd=False):
actions = []
if vlan.loop_protect_external_ports() and vlan.tagged_flood_ports(exclude_unicast):
actions.append(self.flood_table.set_external_forwarding_requested())
actions.extend(self._build_flood_local_rule_actions(
vlan, exclude_unicast, in_port, exclude_all_external, exclude_restricted_bcast_arpnd))
return tuple(actions)
def _build_flood_rule(self, match, command, flood_acts, flood_priority):
return self.flood_table.flowmod(
match=match,
command=command,
inst=[valve_of.apply_actions(flood_acts)],
priority=flood_priority)
@functools.lru_cache(maxsize=1024)
def _vlan_flood_priority(self, eth_type, eth_dst_mask):
priority = self._mask_flood_priority(eth_dst_mask)
if eth_type:
priority += eth_type
return priority
def _build_flood_rule_for_vlan(self, vlan, eth_type, eth_dst, eth_dst_mask, # pylint: disable=too-many-arguments
exclude_unicast, command):
flood_priority = self._vlan_flood_priority(eth_type, eth_dst_mask)
match = self.flood_table.match(
vlan=vlan, eth_type=eth_type, eth_dst=eth_dst, eth_dst_mask=eth_dst_mask)
# TODO: optimization - drop all general flood dsts if all ports are restricted.
exclude_restricted_bcast_arpnd = True
flood_acts = self._build_flood_rule_actions(
vlan, exclude_unicast, None,
exclude_restricted_bcast_arpnd=exclude_restricted_bcast_arpnd)
return (self._build_flood_rule(match, command, flood_acts, flood_priority), flood_acts)
def _build_flood_acts_for_port(self, vlan, exclude_unicast, port, # pylint: disable=too-many-arguments
exclude_all_external=False,
exclude_restricted_bcast_arpnd=False):
flood_acts = ()
port_output_ports = []
port_non_output_acts = []
if port.dyn_phys_up:
if exclude_restricted_bcast_arpnd:
flood_acts = self._build_flood_rule_actions(
vlan, exclude_unicast, port, exclude_all_external, port.restricted_bcast_arpnd)
else:
flood_acts = self._build_flood_rule_actions(
vlan, exclude_unicast, port, exclude_all_external, False)
(flood_acts,
port_output_ports,
port_non_output_acts) = valve_of.output_non_output_actions(flood_acts)
if not port_output_ports:
flood_acts = ()
port_non_output_acts = ()
return (flood_acts, port_output_ports, port_non_output_acts)
def _build_flood_match_priority(self, port, vlan, eth_type, # pylint: disable=too-many-arguments
eth_dst, eth_dst_mask, add_match):
flood_priority = self._vlan_flood_priority(eth_type, eth_dst_mask) + 1
if add_match is None:
add_match = {}
match = self.flood_table.match(
vlan=vlan, in_port=port.number,
eth_type=eth_type, eth_dst=eth_dst, eth_dst_mask=eth_dst_mask,
**add_match)
return (flood_priority, match)
def _build_flood_rule_for_port(self, vlan, eth_type, eth_dst, eth_dst_mask, # pylint: disable=too-many-arguments
command, port, flood_acts, add_match=None):
flood_priority, match = self._build_flood_match_priority(
port, vlan, eth_type, eth_dst, eth_dst_mask, add_match)
return self._build_flood_rule(match, command, flood_acts, flood_priority)
def _build_mask_flood_rules(self, vlan, eth_type, eth_dst, eth_dst_mask, # pylint: disable=too-many-arguments
exclude_unicast, exclude_restricted_bcast_arpnd, command):
ofmsgs = []
if self.combinatorial_port_flood:
for port in self._vlan_all_ports(vlan, exclude_unicast):
flood_acts, _, _ = self._build_flood_acts_for_port(
vlan, exclude_unicast, port,
exclude_restricted_bcast_arpnd=exclude_restricted_bcast_arpnd)
if flood_acts:
ofmsgs.append(self._build_flood_rule_for_port(
vlan, eth_type, eth_dst, eth_dst_mask, command, port, flood_acts))
else:
vlan_flood_ofmsg, vlan_flood_acts = self._build_flood_rule_for_vlan(
vlan, eth_type, eth_dst, eth_dst_mask, exclude_unicast, command)
if not self.use_group_table:
ofmsgs.append(vlan_flood_ofmsg)
(flood_acts,
vlan_output_ports,
vlan_non_output_acts) = valve_of.output_non_output_actions(vlan_flood_acts)
for port in self._vlan_all_ports(vlan, exclude_unicast):
(flood_acts,
port_output_ports,
port_non_output_acts) = self._build_flood_acts_for_port(
vlan, exclude_unicast, port,
exclude_restricted_bcast_arpnd=exclude_restricted_bcast_arpnd)
if not flood_acts:
continue
if (vlan_output_ports - set([port.number]) == port_output_ports and
vlan_non_output_acts == port_non_output_acts):
# Delete a potentially existing port specific flow
# TODO: optimize, avoid generating delete for port if no existing flow.
flood_priority, match = self._build_flood_match_priority(
port, vlan, eth_type, eth_dst, eth_dst_mask, add_match=None)
ofmsgs.append(self.flood_table.flowdel(
match=match, priority=flood_priority))
else:
ofmsgs.append(self._build_flood_rule_for_port(
vlan, eth_type, eth_dst, eth_dst_mask, command, port, flood_acts))
return ofmsgs
def _build_multiout_flood_rules(self, vlan, command):
"""Build flooding rules for a VLAN without using groups."""
ofmsgs = []
for unicast_eth_dst, eth_type, eth_dst, eth_dst_mask in self.flood_dsts:
if unicast_eth_dst and not vlan.unicast_flood:
continue
exclude_restricted_bcast_arpnd = eth_type is None
ofmsgs.extend(self._build_mask_flood_rules(
vlan, eth_type, eth_dst, eth_dst_mask,
unicast_eth_dst, exclude_restricted_bcast_arpnd, command))
return ofmsgs
def _build_group_flood_rules(self, vlan, modify, command):
"""Build flooding rules for a VLAN using groups."""
_, vlan_flood_acts = self._build_flood_rule_for_vlan(
vlan, None, None, None, False, command)
group_id = vlan.vid
group = self.groups.get_entry(
group_id, valve_of.build_group_flood_buckets(vlan_flood_acts))
groups_by_unicast_eth = {False: group, True: group}
ofmsgs = []
# Only configure unicast flooding group if has different output
# actions to non unicast flooding.
_, unicast_eth_vlan_flood_acts = self._build_flood_rule_for_vlan(
vlan, None, None, None, True, command)
unicast_eth_vlan_flood_acts, unicast_output_ports, _ = valve_of.output_non_output_actions(
unicast_eth_vlan_flood_acts)
vlan_flood_acts, vlan_output_ports, _ = valve_of.output_non_output_actions(vlan_flood_acts)
if unicast_output_ports != vlan_output_ports:
group_id += valve_of.VLAN_GROUP_OFFSET
group = self.groups.get_entry(
group_id, valve_of.build_group_flood_buckets(unicast_eth_vlan_flood_acts))
groups_by_unicast_eth[True] = group
for group in groups_by_unicast_eth.values():
if modify:
ofmsgs.append(group.modify())
else:
ofmsgs.extend(group.add())
for unicast_eth_dst, eth_type, eth_dst, eth_dst_mask in self.flood_dsts:
if unicast_eth_dst and not vlan.unicast_flood:
continue
group = groups_by_unicast_eth[unicast_eth_dst]
match = self.flood_table.match(
vlan=vlan, eth_type=eth_type, eth_dst=eth_dst, eth_dst_mask=eth_dst_mask)
flood_priority = self._vlan_flood_priority(eth_type, eth_dst_mask)
ofmsgs.append(self.flood_table.flowmod(
match=match,
command=command,
inst=[valve_of.apply_actions([valve_of.group_act(group.group_id)])],
priority=flood_priority))
return ofmsgs
[docs] def add_vlan(self, vlan):
ofmsgs = []
ofmsgs.append(self.eth_src_table.flowcontroller(
match=self.eth_src_table.match(vlan=vlan),
priority=self.low_priority,
inst=[self.eth_src_table.goto(self.output_table)]))
ofmsgs.extend(self.build_flood_rules(vlan))
return ofmsgs
[docs] def del_vlan(self, vlan):
return [self.flood_table.flowdel(self.flood_table.match(vlan=vlan.vid))]
[docs] def update_vlan(self, vlan):
return self.build_flood_rules(vlan, modify=True)
def _find_forwarding_table(self, vlan):
if vlan.acls_in:
return self.vlan_acl_table
return self.classification_table()
def _port_add_vlan_rules(self, port, vlan, mirror_act, push_vlan=True):
actions = copy.copy(mirror_act)
match_vlan = vlan
if push_vlan:
actions.extend(valve_of.push_vlan_act(
self.vlan_table, vlan.vid))
match_vlan = NullVLAN()
if self.has_externals:
if port.loop_protect_external:
actions.append(self.vlan_table.set_no_external_forwarding_requested())
else:
actions.append(self.vlan_table.set_external_forwarding_requested())
inst = [
valve_of.apply_actions(actions),
self.vlan_table.goto(self._find_forwarding_table(vlan))]
return self.vlan_table.flowmod(
self.vlan_table.match(in_port=port.number, vlan=match_vlan),
priority=self.low_priority, inst=inst)
def _native_vlan(self, port):
for native_vlan in (port.dyn_dot1x_native_vlan, port.native_vlan):
if native_vlan is not None:
return native_vlan
return None
[docs] def add_port(self, port):
if port.vlans():
mirror_act = port.mirror_actions()
tagged_ofmsgs = []
for vlan in port.tagged_vlans:
tagged_ofmsgs.append(self._port_add_vlan_rules(
port, vlan, mirror_act, push_vlan=False))
untagged_ofmsgs = []
native_vlan = self._native_vlan(port)
if native_vlan is not None:
untagged_ofmsgs.append(self._port_add_vlan_rules(
port, native_vlan, mirror_act))
# If no untagged VLANs, add explicit drop rule for untagged packets.
if port.count_untag_vlan_miss and not untagged_ofmsgs:
untagged_ofmsgs.append(self.vlan_table.flowmod(
self.vlan_table.match(in_port=port.number, vlan=NullVLAN()),
priority=self.low_priority))
return tagged_ofmsgs + untagged_ofmsgs
return []
[docs] def del_port(self, port):
ofmsgs = []
ofmsgs.append(
self.eth_src_table.flowdel(self.eth_src_table.match(in_port=port.number)))
for table in (self.eth_dst_table, self.eth_dst_hairpin_table):
if table:
# per OF 1.3.5 B.6.23, the OFA will match flows
# that have an action targeting this port.
ofmsgs.append(table.flowdel(out_port=port.number))
for vlan in port.vlans():
vlan.clear_cache_hosts_on_port(port)
native_vlan = self._native_vlan(port)
if native_vlan is not None:
ofmsgs.append(self.vlan_table.flowdel(
self.vlan_table.match(in_port=port.number, vlan=port.native_vlan),
priority=self.low_priority))
return ofmsgs
[docs] def build_flood_rules(self, vlan, modify=False):
"""Add flows to flood packets to unknown destinations on a VLAN."""
command = valve_of.ofp.OFPFC_ADD
if modify:
command = valve_of.ofp.OFPFC_MODIFY_STRICT
ofmsgs = self._build_multiout_flood_rules(vlan, command)
if self.use_group_table:
ofmsgs.extend(self._build_group_flood_rules(vlan, modify, command))
return ofmsgs
[docs] @staticmethod
def update_stack_topo(event, dp, port): # pylint: disable=unused-argument,invalid-name
"""Update the stack topology. It has nothing to do for non-stacking DPs."""
return
[docs] @staticmethod
def edge_learn_port(_other_valves, pkt_meta):
"""Possibly learn a host on a port.
Args:
other_valves (list): All Valves other than this one.
pkt_meta (PacketMeta): PacketMeta instance for packet received.
Returns:
port to learn host on.
"""
return pkt_meta.port
[docs] def ban_rules(self, pkt_meta):
"""Limit learning to a maximum configured on this port/VLAN.
Args:
pkt_meta: PacketMeta instance.
Returns:
list: OpenFlow messages, if any.
"""
ofmsgs = []
port = pkt_meta.port
eth_src = pkt_meta.eth_src
vlan = pkt_meta.vlan
entry = vlan.cached_host(eth_src)
if entry is None:
if port.max_hosts:
if port.hosts_count() == port.max_hosts:
ofmsgs.append(self._temp_ban_host_learning(
self.eth_src_table.match(in_port=port.number)))
port.dyn_learn_ban_count += 1
self.logger.info(
'max hosts %u reached on %s, '
'temporarily banning learning on this port, '
'and not learning %s' % (
port.max_hosts, port, eth_src))
if vlan is not None and vlan.max_hosts:
hosts_count = vlan.hosts_count()
if hosts_count == vlan.max_hosts:
ofmsgs.append(self._temp_ban_host_learning(self.eth_src_table.match(vlan=vlan)))
vlan.dyn_learn_ban_count += 1
self.logger.info(
'max hosts %u reached on VLAN %u, '
'temporarily banning learning on this VLAN, '
'and not learning %s on %s' % (
vlan.max_hosts, vlan.vid, eth_src, port))
return ofmsgs
def _temp_ban_host_learning(self, match):
return self.eth_src_table.flowdrop(
match,
priority=(self.low_priority + 1),
hard_timeout=self.learn_ban_timeout)
[docs] def delete_host_from_vlan(self, eth_src, vlan):
"""Delete a host from a VLAN."""
ofmsgs = [self.eth_src_table.flowdel(
self.eth_src_table.match(vlan=vlan, eth_src=eth_src))]
for table in (self.eth_dst_table, self.eth_dst_hairpin_table):
if table:
ofmsgs.append(table.flowdel(table.match(vlan=vlan, eth_dst=eth_src)))
return ofmsgs
[docs] def expire_hosts_from_vlan(self, vlan, now):
"""Expire hosts from VLAN cache."""
expired_hosts = vlan.expire_cache_hosts(now, self.learn_timeout)
if expired_hosts:
vlan.dyn_last_time_hosts_expired = now
self.logger.info(
'%u recently active hosts on VLAN %u, expired %s' % (
vlan.hosts_count(), vlan.vid, expired_hosts))
return expired_hosts
def _jitter_learn_timeout(self, base_learn_timeout, port, eth_dst):
"""Calculate jittered learning timeout to avoid synchronized host timeouts."""
# Hosts on this port never timeout.
if port.permanent_learn:
return 0
if not base_learn_timeout:
return 0
# Jitter learn timeout based on eth address, so timeout processing is jittered,
# the same hosts will timeout approximately the same time on a stack.
jitter = hash(eth_dst) % self.learn_jitter
min_learn_timeout = base_learn_timeout - self.learn_jitter
return int(max(abs(min_learn_timeout + jitter), self.cache_update_guard_time))
def _learn_host_timeouts(self, port, eth_src):
"""Calculate flow timeouts for learning on a port."""
learn_timeout = self._jitter_learn_timeout(self.learn_timeout, port, eth_src)
# Update datapath to no longer send packets from this mac to controller
# note the use of hard_timeout here and idle_timeout for the dst table
# this is to ensure that the source rules will always be deleted before
# any rules on the dst table. Otherwise if the dst table rule expires
# but the src table rule is still being hit intermittantly the switch
# will flood packets to that dst and not realise it needs to relearn
# the rule
# NB: Must be lower than highest priority otherwise it can match
# flows destined to controller
src_rule_idle_timeout = 0
src_rule_hard_timeout = learn_timeout
dst_rule_idle_timeout = learn_timeout + self.cache_update_guard_time
if not self.idle_dst:
dst_rule_idle_timeout = 0
return (src_rule_idle_timeout, src_rule_hard_timeout, dst_rule_idle_timeout)
def _external_forwarding_requested(self, port): # pylint: disable=unused-argument
if self.has_externals:
return True
return None
[docs] def learn_host_on_vlan_port_flows(self, port, vlan, eth_src,
delete_existing, refresh_rules,
src_rule_idle_timeout,
src_rule_hard_timeout,
dst_rule_idle_timeout):
"""Return flows that implement learning a host on a port."""
ofmsgs = []
# Delete any existing entries for MAC.
if delete_existing:
ofmsgs.extend(self.delete_host_from_vlan(eth_src, vlan))
# Associate this MAC with source port.
src_match = self.eth_src_table.match(
in_port=port.number, vlan=vlan, eth_src=eth_src)
src_priority = self.host_priority - 1
inst = []
inst.append(self.eth_src_table.goto(self.output_table))
ofmsgs.append(self.eth_src_table.flowmod(
match=src_match,
priority=src_priority,
inst=inst,
hard_timeout=src_rule_hard_timeout,
idle_timeout=src_rule_idle_timeout))
hairpinning = port.hairpin or port.hairpin_unicast
# If we are refreshing only and not in hairpin mode, leave existing eth_dst alone.
if refresh_rules and not hairpinning:
return ofmsgs
match_dict = {
'vlan': vlan, 'eth_dst': eth_src, valve_of.EXTERNAL_FORWARDING_FIELD: None}
if self.has_externals:
match_dict.update({
valve_of.EXTERNAL_FORWARDING_FIELD: valve_of.PCP_EXT_PORT_FLAG})
inst = self.pipeline.output(
port, vlan, external_forwarding_requested=self._external_forwarding_requested(port))
# Output packets for this MAC to specified port.
ofmsgs.append(self.eth_dst_table.flowmod(
self.eth_dst_table.match(**match_dict),
priority=self.host_priority,
inst=inst,
idle_timeout=dst_rule_idle_timeout))
if self.has_externals and not port.loop_protect_external:
match_dict.update({
valve_of.EXTERNAL_FORWARDING_FIELD: valve_of.PCP_NONEXT_PORT_FLAG})
ofmsgs.append(self.eth_dst_table.flowmod(
self.eth_dst_table.match(**match_dict),
priority=self.host_priority,
inst=inst,
idle_timeout=dst_rule_idle_timeout))
# If port is in hairpin mode, install a special rule
# that outputs packets destined to this MAC back out the same
# port they came in (e.g. multiple hosts on same WiFi AP,
# and FAUCET is switching between them on the same port).
if hairpinning:
ofmsgs.append(self.eth_dst_hairpin_table.flowmod(
self.eth_dst_hairpin_table.match(in_port=port.number, vlan=vlan, eth_dst=eth_src),
priority=self.host_priority,
inst=self.pipeline.output(port, vlan, hairpin=True),
idle_timeout=dst_rule_idle_timeout))
return ofmsgs
def _perm_learn_check(self, entry, vlan, now, eth_src, port, ofmsgs, # pylint: disable=unused-argument
cache_port, cache_age,
delete_existing, refresh_rules):
learn_exit = False
update_cache = True
if entry is not None and entry.port.permanent_learn:
if entry.port != port:
ofmsgs.extend(self.pipeline.filter_packets(
{'eth_src': eth_src, 'in_port': port.number}))
learn_exit = True
update_cache = False
return (learn_exit, ofmsgs, cache_port, update_cache, delete_existing, refresh_rules)
def _learn_cache_check(self, entry, vlan, now, eth_src, port, ofmsgs, # pylint: disable=unused-argument
cache_port, cache_age,
delete_existing, refresh_rules):
learn_exit = False
update_cache = True
if cache_port is not None:
# packet was received on same member of a LAG.
same_lag = (port.lacp and port.lacp == cache_port.lacp)
guard_time = self.cache_update_guard_time
if cache_port == port or same_lag:
# aggressively re-learn on LAGs
if same_lag:
guard_time = 2
# port didn't change status, and recent cache update, don't do anything.
if (cache_age < guard_time and
port.dyn_update_time is not None and
port.dyn_update_time <= entry.cache_time):
update_cache = False
learn_exit = True
# skip delete if host didn't change ports or on same LAG.
elif cache_port == port or same_lag:
delete_existing = False
refresh_rules = True
return (learn_exit, ofmsgs, cache_port, update_cache, delete_existing, refresh_rules)
def _loop_protect_check(self, entry, vlan, now, eth_src, port, ofmsgs, # pylint: disable=unused-argument
cache_port, cache_age,
delete_existing, refresh_rules):
learn_exit = False
update_cache = True
if port.loop_protect:
ban_age = None
learn_ban = False
# if recently in loop protect mode and still receiving packets,
# prolong the ban
if port.dyn_last_ban_time:
ban_age = now - port.dyn_last_ban_time
if ban_age < self.cache_update_guard_time:
learn_ban = True
# if not in protect mode and we get a rapid move, enact protect mode
if not learn_ban and entry is not None:
if port != cache_port and cache_age < self.cache_update_guard_time:
learn_ban = True
port.dyn_learn_ban_count += 1
self.logger.info('rapid move of %s from %s to %s, temp loop ban %s' % (
eth_src, cache_port, port, port))
# already, or newly in protect mode, apply the ban rules.
if learn_ban:
port.dyn_last_ban_time = now
ofmsgs.append(self._temp_ban_host_learning(
self.eth_src_table.match(in_port=port.number)))
learn_exit = True
return (learn_exit, ofmsgs, cache_port, update_cache, delete_existing, refresh_rules)
def _learn_check(self, entry, vlan, now, eth_src, port, ofmsgs, # pylint: disable=unused-argument
cache_port, cache_age,
delete_existing, refresh_rules):
learn_exit = True
update_cache = True
(src_rule_idle_timeout,
src_rule_hard_timeout,
dst_rule_idle_timeout) = self._learn_host_timeouts(port, eth_src)
ofmsgs.extend(self.learn_host_on_vlan_port_flows(
port, vlan, eth_src, delete_existing, refresh_rules,
src_rule_idle_timeout, src_rule_hard_timeout,
dst_rule_idle_timeout))
return (learn_exit, ofmsgs, cache_port, update_cache, delete_existing, refresh_rules)
[docs] def learn_host_on_vlan_ports(self, now, port, vlan, eth_src,
delete_existing=True,
last_dp_coldstart_time=None):
"""Learn a host on a port."""
ofmsgs = []
cache_port = None
cache_age = None
refresh_rules = False
update_cache = True
entry = vlan.cached_host(eth_src)
# Host not cached, and no hosts expired since we cold started
# Enable faster learning by assuming there's no previous host to delete
if entry is None:
if (last_dp_coldstart_time and
(vlan.dyn_last_time_hosts_expired is None or
vlan.dyn_last_time_hosts_expired < last_dp_coldstart_time)):
delete_existing = False
else:
cache_age = now - entry.cache_time
cache_port = entry.port
for learn_func in (
self._perm_learn_check, self._learn_cache_check,
self._loop_protect_check, self._learn_check):
(learn_exit, ofmsgs, cache_port, update_cache,
delete_existing, refresh_rules) = learn_func(
entry, vlan, now, eth_src, port, ofmsgs, cache_port, cache_age,
delete_existing, refresh_rules)
if learn_exit:
break
return (ofmsgs, cache_port, update_cache)
[docs] def flow_timeout(self, _now, _table_id, _match):
"""Handle a flow timed out message from dataplane."""
return []
[docs]class ValveSwitchFlowRemovedManager(ValveSwitchManager):
"""Trigger relearning on flow removed notifications.
.. note::
not currently reliable.
"""
[docs] def flow_timeout(self, now, table_id, match):
ofmsgs = []
if table_id in (self.eth_src_table.table_id, self.eth_dst_table.table_id):
if 'vlan_vid' in match:
vlan = self.vlans[valve_of.devid_present(match['vlan_vid'])]
in_port = None
eth_src = None
eth_dst = None
for field, value in match.items():
if field == 'in_port':
in_port = value
elif field == 'eth_src':
eth_src = value
elif field == 'eth_dst':
eth_dst = value
if eth_src and in_port:
port = self.ports[in_port]
ofmsgs.extend(self._src_rule_expire(vlan, port, eth_src))
elif eth_dst:
ofmsgs.extend(self._dst_rule_expire(now, vlan, eth_dst))
return ofmsgs
[docs] def expire_hosts_from_vlan(self, _vlan, _now):
return []
def _learn_host_timeouts(self, port, eth_src):
"""Calculate flow timeouts for learning on a port."""
learn_timeout = self._jitter_learn_timeout(self.learn_timeout, port, eth_src)
# Disable hard_time, dst rule expires after src rule.
src_rule_idle_timeout = learn_timeout
src_rule_hard_timeout = 0
dst_rule_idle_timeout = learn_timeout + self.cache_update_guard_time
return (src_rule_idle_timeout, src_rule_hard_timeout, dst_rule_idle_timeout)
def _src_rule_expire(self, vlan, port, eth_src):
"""When a src rule expires, the host is probably inactive or active in
receiving but not sending. We mark just mark the host as expired."""
ofmsgs = []
entry = vlan.cached_host_on_port(eth_src, port)
if entry is not None:
vlan.expire_cache_host(eth_src)
self.logger.info('expired src_rule for host %s' % eth_src)
return ofmsgs
def _dst_rule_expire(self, now, vlan, eth_dst):
"""Expiring a dst rule may indicate that the host is actively sending
traffic but not receving. If the src rule not yet expires, we reinstall
host rules."""
ofmsgs = []
entry = vlan.cached_host(eth_dst)
if entry is not None:
ofmsgs.extend(self.learn_host_on_vlan_ports(
now, entry.port, vlan, eth_dst, delete_existing=False))
self.logger.info(
'refreshing host %s from VLAN %u' % (eth_dst, vlan.vid))
return ofmsgs