class Peer (object):
def __init__ (self, neighbor, reactor):
try:
self.logger = Logger()
# We only to try to connect via TCP once
self.once = environment.settings().tcp.once
self.bind = True if environment.settings().tcp.bind else False
except RuntimeError:
self.logger = FakeLogger()
self.once = False
self.bind = True
now = time.time()
self.reactor = reactor
self.neighbor = neighbor
# The next restart neighbor definition
self._neighbor = None
self.proto = None
self.fsm = FSM(self,FSM.IDLE)
self.stats = {
'fsm': self.fsm,
'creation': now,
'complete': now,
}
self.generator = None
# The peer should restart after a stop
self._restart = True
# The peer was restarted (to know what kind of open to send for graceful restart)
self._restarted = FORCE_GRACEFUL
# We want to remove routes which are not in the configuration anymote afte a signal to reload
self._reconfigure = True
# We want to send all the known routes
self._resend_routes = SEND.DONE
# We have new routes for the peers
self._have_routes = True
# We have been asked to teardown the session with this code
self._teardown = None
self._delay = Delay()
self.recv_timer = None
def _reset (self, message='',error=''):
self.fsm.change(FSM.IDLE)
self.stats = {
'fsm': self.fsm,
'creation': self.stats['creation'],
'complete': self.stats['creation'],
}
if self.proto:
self.proto.close(u"peer reset, message [{0}] error[{1}]".format(message, error))
self._delay.increase()
self.proto = None
if not self._restart or self.neighbor.generated:
self.generator = False
return
self.generator = None
self._teardown = None
self.neighbor.rib.reset()
# If we are restarting, and the neighbor definition is different, update the neighbor
if self._neighbor:
self.neighbor = self._neighbor
self._neighbor = None
def _stop (self, message):
self.generator = False
self.proto.close('stop, message [%s]' % message)
self.proto = None
# logging
def me (self, message):
return "peer %s ASN %-7s %s" % (self.neighbor.peer_address,self.neighbor.peer_as,message)
# control
def stop (self):
self._teardown = 3
self._restart = False
self._restarted = False
self._delay.reset()
self.fsm.change(FSM.IDLE)
self.stats = {
'fsm': self.fsm,
'creation': self.stats['creation'],
'reset': time.time(),
}
self.neighbor.rib.uncache()
def resend (self):
self._resend_routes = SEND.NORMAL
self._delay.reset()
def schedule_rib_check (self, changes=None, update=None):
if changes:
self.neighbor.rib.outgoing.replace(changes)
self._have_routes = self.neighbor.flush if update is None else update
def reestablish (self, restart_neighbor=None):
# we want to tear down the session and re-establish it
self._teardown = 3
self._restart = True
self._restarted = True
self._resend_routes = SEND.NORMAL
self._neighbor = restart_neighbor
self._delay.reset()
def reconfigure (self, restart_neighbor=None):
# we want to update the route which were in the configuration file
self._reconfigure = True
self._neighbor = restart_neighbor
self._resend_routes = SEND.NORMAL
self._neighbor = restart_neighbor
def teardown (self, code, restart=True):
self._restart = restart
self._teardown = code
self._delay.reset()
# sockets we must monitor
def sockets (self):
ios = []
if self.proto and self.proto.connection and self.proto.connection.io:
ios.append(self.proto.connection.io)
return ios
def handle_connection (self, connection):
# if the other side fails, we go back to idle
if self.fsm == FSM.ESTABLISHED:
self.logger.network('we already have a peer in state established for %s' % connection.name())
return connection.notification(6,7,b'could not accept the connection, already established')
# 6.8 The convention is to compare the BGP Identifiers of the peers
# involved in the collision and to retain only the connection initiated
# by the BGP speaker with the higher-valued BGP Identifier.
# FSM.IDLE , FSM.ACTIVE , FSM.CONNECT , FSM.OPENSENT , FSM.OPENCONFIRM , FSM.ESTABLISHED
if self.fsm == FSM.OPENCONFIRM:
# We cheat: we are not really reading the OPEN, we use the data we have instead
# it does not matter as the open message will be the same anyway
local_id = self.neighbor.router_id.pack()
remote_id = self.proto.negotiated.received_open.router_id.pack()
if remote_id < local_id:
self.logger.network('closing incoming connection as we have an outgoing connection with higher router-id for %s' % connection.name())
return connection.notification(6,7,b'could not accept the connection, as another connection is already in open-confirm and will go through')
# accept the connection
if self.proto:
self.proto.close('closing outgoing connection as we have another incoming on with higher router-id')
self.proto = Protocol(self).accept(connection)
self.generator = None
# Let's make sure we do some work with this connection
self._delay.reset()
return None
def established (self):
return self.fsm == FSM.ESTABLISHED
def negotiated_families(self):
if self.proto:
families = ["%s/%s" % (x[0], x[1]) for x in self.proto.negotiated.families]
else:
families = ["%s/%s" % (x[0], x[1]) for x in self.neighbor.families()]
if len(families) > 1:
return "[ %s ]" % " ".join(families)
elif len(families) == 1:
return families[0]
return ''
def _connect (self):
proto = Protocol(self)
generator = proto.connect()
connected = False
try:
while not connected:
if self._teardown:
raise StopIteration()
connected = six.next(generator)
# we want to come back as soon as possible
yield ACTION.LATER
self.proto = proto
except StopIteration:
# Connection failed
if not connected and self.proto:
self.proto.close('connection to %s:%d failed' % (self.neighbor.peer_address,self.neighbor.connect))
# A connection arrived before we could establish !
if not connected or self.proto:
yield ACTION.NOW
raise Interrupted()
def _send_open (self):
message = Message.CODE.NOP
for message in self.proto.new_open():
if ordinal(message.TYPE) == Message.CODE.NOP:
yield ACTION.NOW
yield message
def _read_open (self):
wait = environment.settings().bgp.openwait
opentimer = ReceiveTimer(self.proto.connection.session,wait,1,1,'waited for open too long, we do not like stuck in active')
# Only yield if we have not the open, otherwise the reactor can run the other connection
# which would be bad as we need to do the collission check without going to the other peer
for message in self.proto.read_open(self.neighbor.peer_address.top()):
opentimer.check_ka(message)
# XXX: FIXME: change the whole code to use the ord and not the chr version
# Only yield if we have not the open, otherwise the reactor can run the other connection
# which would be bad as we need to do the collission check
if ordinal(message.TYPE) == Message.CODE.NOP:
yield ACTION.NOW
yield message
def _send_ka (self):
for message in self.proto.new_keepalive('OPENCONFIRM'):
yield ACTION.NOW
def _read_ka (self):
# Start keeping keepalive timer
for message in self.proto.read_keepalive():
self.recv_timer.check_ka(message)
yield ACTION.NOW
def _establish (self):
# try to establish the outgoing connection
self.fsm.change(FSM.ACTIVE)
if not self.proto:
for action in self._connect():
if action in ACTION.ALL:
yield action
self.fsm.change(FSM.CONNECT)
# normal sending of OPEN first ...
if self.neighbor.local_as:
for sent_open in self._send_open():
if sent_open in ACTION.ALL:
yield sent_open
self.proto.negotiated.sent(sent_open)
self.fsm.change(FSM.OPENSENT)
# read the peer's open
for received_open in self._read_open():
if received_open in ACTION.ALL:
yield received_open
self.proto.negotiated.received(received_open)
# if we mirror the ASN, we need to read first and send second
if not self.neighbor.local_as:
for sent_open in self._send_open():
if sent_open in ACTION.ALL:
yield sent_open
self.proto.negotiated.sent(sent_open)
self.fsm.change(FSM.OPENSENT)
self.proto.validate_open()
self.fsm.change(FSM.OPENCONFIRM)
self.recv_timer = ReceiveTimer(self.proto.connection.session,self.proto.negotiated.holdtime,4,0)
for action in self._send_ka():
yield action
for action in self._read_ka():
yield action
self.fsm.change(FSM.ESTABLISHED)
self.stats['complete'] = time.time()
# let the caller know that we were sucesfull
yield ACTION.NOW
def _main (self):
"""yield True if we want to come back to it asap, None if nothing urgent, and False if stopped"""
if self._teardown:
raise Notify(6,3)
include_withdraw = False
# Announce to the process BGP is up
self.logger.network('Connected to peer %s' % self.neighbor.name())
self.stats['up'] = self.stats.get('up',0) + 1
if self.neighbor.api['neighbor-changes']:
try:
self.reactor.processes.up(self.neighbor)
except ProcessError:
# Can not find any better error code than 6,0 !
# XXX: We can not restart the program so this will come back again and again - FIX
# XXX: In the main loop we do exit on this kind of error
raise Notify(6,0,'ExaBGP Internal error, sorry.')
send_eor = not self.neighbor.manual_eor
new_routes = None
self._resend_routes = SEND.NORMAL
send_families = []
# Every last asm message should be re-announced on restart
for family in self.neighbor.asm:
if family in self.neighbor.families():
self.neighbor.messages.appendleft(self.neighbor.asm[family])
operational = None
refresh = None
command_eor = None
number = 0
refresh_enhanced = True if self.proto.negotiated.refresh == REFRESH.ENHANCED else False
send_ka = KA(self.proto.connection.session,self.proto)
while not self._teardown:
for message in self.proto.read_message():
self.recv_timer.check_ka(message)
if send_ka() is not False:
# we need and will send a keepalive
while send_ka() is None:
yield ACTION.NOW
# Received update
if message.TYPE == Update.TYPE:
number += 1
self.logger.routes('%s << UPDATE #%d' % (self.proto.connection.session(),number))
for nlri in message.nlris:
self.neighbor.rib.incoming.update_cache(Change(nlri,message.attributes))
self.logger.routes(LazyFormat('<< UPDATE #%d nlri ' % number,nlri,str),source=self.proto.connection.session())
elif message.TYPE == RouteRefresh.TYPE:
if message.reserved == RouteRefresh.request:
self._resend_routes = SEND.REFRESH
send_families.append((message.afi,message.safi))
# SEND OPERATIONAL
if self.neighbor.operational:
if not operational:
new_operational = self.neighbor.messages.popleft() if self.neighbor.messages else None
if new_operational:
operational = self.proto.new_operational(new_operational,self.proto.negotiated)
if operational:
try:
six.next(operational)
except StopIteration:
operational = None
# make sure that if some operational message are received via the API
# that we do not eat memory for nothing
elif self.neighbor.messages:
self.neighbor.messages.popleft()
# SEND REFRESH
if self.neighbor.route_refresh:
if not refresh:
new_refresh = self.neighbor.refresh.popleft() if self.neighbor.refresh else None
if new_refresh:
refresh = self.proto.new_refresh(new_refresh)
if refresh:
try:
six.next(refresh)
except StopIteration:
refresh = None
# Take the routes already sent to that peer and resend them
if self._reconfigure:
self._reconfigure = False
# we are here following a configuration change
if self._neighbor:
# see what changed in the configuration
self.neighbor.rib.outgoing.replace(self._neighbor.backup_changes,self._neighbor.changes)
# do not keep the previous routes in memory as they are not useful anymore
self._neighbor.backup_changes = []
self._have_routes = True
# Take the routes already sent to that peer and resend them
if self._resend_routes != SEND.DONE:
enhanced = True if refresh_enhanced and self._resend_routes == SEND.REFRESH else False
self._resend_routes = SEND.DONE
self.neighbor.rib.outgoing.resend(send_families,enhanced)
self._have_routes = True
send_families = []
# Need to send update
if self._have_routes and not new_routes:
self._have_routes = False
# XXX: in proto really. hum to think about ?
new_routes = self.proto.new_update(include_withdraw)
if new_routes:
try:
count = 20
while count:
# This can raise a NetworkError
six.next(new_routes)
count -= 1
except StopIteration:
new_routes = None
include_withdraw = True
elif send_eor:
send_eor = False
for _ in self.proto.new_eors():
yield ACTION.NOW
self.logger.message('>> EOR(s)')
# SEND MANUAL KEEPALIVE (only if we have no more routes to send)
elif not command_eor and self.neighbor.eor:
new_eor = self.neighbor.eor.popleft()
command_eor = self.proto.new_eors(new_eor.afi,new_eor.safi)
if command_eor:
try:
six.next(command_eor)
except StopIteration:
command_eor = None
if new_routes or message.TYPE != NOP.TYPE:
yield ACTION.NOW
elif self.neighbor.messages or operational:
yield ACTION.NOW
elif self.neighbor.eor or command_eor:
yield ACTION.NOW
else:
yield ACTION.LATER
# read_message will loop until new message arrives with NOP
if self._teardown:
break
# If graceful restart, silent shutdown
if self.neighbor.graceful_restart and self.proto.negotiated.sent_open.capabilities.announced(Capability.CODE.GRACEFUL_RESTART):
self.logger.network('Closing the session without notification','error')
self.proto.close('graceful restarted negotiated, closing without sending any notification')
raise NetworkError('closing')
# notify our peer of the shutdown
raise Notify(6,self._teardown)
def _run (self):
"""yield True if we want the reactor to give us back the hand with the same peer loop, None if we do not have any more work to do"""
try:
for action in self._establish():
yield action
for action in self._main():
yield action
# CONNECTION FAILURE
except NetworkError as network:
# we tried to connect once, it failed and it was not a manual request, we stop
if self.once and not self._teardown:
self.logger.network('only one attempt to connect is allowed, stopping the peer')
self.stop()
self._reset('closing connection',network)
return
# NOTIFY THE PEER OF AN ERROR
except Notify as notify:
if self.proto:
try:
generator = self.proto.new_notification(notify)
try:
while True:
six.next(generator)
yield ACTION.NOW
except StopIteration:
pass
except (NetworkError,ProcessError):
self.logger.network('NOTIFICATION NOT SENT','error')
self._reset('notification sent (%d,%d)' % (notify.code,notify.subcode),notify)
else:
self._reset()
return
# THE PEER NOTIFIED US OF AN ERROR
except Notification as notification:
# we tried to connect once, it failed and it was not a manual request, we stop
if self.once and not self._teardown:
self.logger.network('only one attempt to connect is allowed, stopping the peer')
self.stop()
self._reset(
'notification received (%d,%d)' % (
notification.code,
notification.subcode),
notification
)
return
# RECEIVED a Message TYPE we did not expect
except Message as message:
self._reset('unexpected message received',message)
return
# PROBLEM WRITING TO OUR FORKED PROCESSES
except ProcessError as process:
self._reset('process problem',process)
return
# ....
except Interrupted as interruption:
self._reset('connection received before we could fully establish one')
return
# UNHANDLED PROBLEMS
except Exception as exc:
# Those messages can not be filtered in purpose
self.logger.raw('\n'.join([
NO_PANIC,
'',
'',
str(type(exc)),
str(exc),
trace(),
FOOTER
]))
self._reset()
return
# loop
def run (self):
if self.reactor.processes.broken(self.neighbor):
# XXX: we should perhaps try to restart the process ??
self.logger.processes('ExaBGP lost the helper process for this peer - stopping','error')
if self.reactor.processes.terminate_on_error:
self.reactor.api_shutdown()
else:
self.stop()
return True
if self.generator:
try:
# This generator only stops when it raises
# otherwise return one of the ACTION
return six.next(self.generator)
except StopIteration:
# Trying to run a closed loop, no point continuing
self.generator = None
if self._restart:
return ACTION.LATER
return ACTION.CLOSE
elif self.generator is None:
if self.fsm in [FSM.OPENCONFIRM,FSM.ESTABLISHED]:
self.logger.network('stopping, other connection is established','debug')
self.generator = False
return ACTION.LATER
if self._delay.backoff():
return ACTION.LATER
if self._restart:
self.logger.network('initialising connection to %s' % self.neighbor.name(),'debug')
self.generator = self._run()
return ACTION.LATER # make sure we go through a clean loop
return ACTION.CLOSE
def cli_data (self):
def tri (value):
if value is None:
return None
return True if value else False
peer = defaultdict(lambda: None)
have_peer = self.proto is not None
have_open = self.proto and self.proto.negotiated.received_open
if have_peer:
peer.update({
'multi-session': self.proto.negotiated.multisession,
'operational': self.proto.negotiated.operational,
})
if have_open:
capa = self.proto.negotiated.received_open.capabilities
peer.update({
'router-id': self.proto.negotiated.received_open.router_id,
'hold-time': self.proto.negotiated.received_open.hold_time,
'asn4': self.proto.negotiated.asn4,
'route-refresh': capa.announced(Capability.CODE.ROUTE_REFRESH),
'multi-session': capa.announced(Capability.CODE.MULTISESSION) or capa.announced(Capability.CODE.MULTISESSION_CISCO),
'add-path': capa.announced(Capability.CODE.ADD_PATH),
'graceful-restart': capa.announced(Capability.CODE.GRACEFUL_RESTART),
})
capabilities = {
'asn4': (tri(self.neighbor.asn4), tri(peer['asn4'])),
'route-refresh': (tri(self.neighbor.route_refresh),tri(peer['route-refresh'])),
'multi-session': (tri(self.neighbor.multisession), tri(peer['multi-session'])),
'operational': (tri(self.neighbor.operational), tri(peer['operational'])),
'add-path': (tri(self.neighbor.add_path),tri(peer['add-path'])),
'graceful-restart': (tri(self.neighbor.graceful_restart),tri(peer['graceful-restart'])),
}
families = {}
for family in self.neighbor.families():
if have_open:
common = True if family in self.proto.negotiated.families else False
addpath = self.proto.negotiated.addpath.receive(*family) and self.proto.negotiated.addpath.receive(*family)
else:
common = False
addpath = False
families[family] = (True,common if have_open else None,addpath)
messages = {}
total_sent = 0
total_rcvd = 0
for message in ('open','notification','keepalive','update','refresh'):
sent = self.stats.get('send-%s' % message,0)
rcvd = self.stats.get('receive-%s' % message,0)
total_sent += sent
total_rcvd += rcvd
messages[message] = (sent, rcvd)
messages['total'] = (total_sent, total_rcvd)
return {
'duration': int(time.time() - self.stats['complete']) if self.stats['complete'] else 0,
'local-address': str(self.neighbor.local_address),
'peer-address': str(self.neighbor.peer_address),
'local-as': int(self.neighbor.local_as),
'peer-as': int(self.neighbor.peer_as),
'local-id': str(self.neighbor.router_id),
'peer-id': None if peer['peer-id'] is None else str(peer['router-id']),
'local-hold': int(self.neighbor.hold_time),
'peer-hold': None if peer['hold-time'] is None else int(peer['hold-time']),
'state': self.fsm.name(),
'capabilities': capabilities,
'families': families,
'messages': messages,
}
class Peer(object):
def __init__(self, neighbor, reactor):
try:
self.logger = Logger()
# We only to try to connect via TCP once
self.once = environment.settings().tcp.once
self.bind = True if environment.settings().tcp.bind else False
except RuntimeError:
self.logger = FakeLogger()
self.once = False
self.bind = True
self.reactor = reactor
self.neighbor = neighbor
# The next restart neighbor definition
self._neighbor = None
# The peer should restart after a stop
self._restart = True
# The peer was restarted (to know what kind of open to send for graceful restart)
self._restarted = FORCE_GRACEFUL
# We want to remove routes which are not in the configuration anymote afte a signal to reload
self._reconfigure = True
# We want to send all the known routes
self._resend_routes = SEND.DONE
# We have new routes for the peers
self._have_routes = True
# We have been asked to teardown the session with this code
self._teardown = None
self._delay = Delay()
self.recv_timer = None
self._incoming = Direction('in', self._accept, FSM(FSM.IDLE), None,
False, False)
self._outgoing = Direction(
'out', self._connect, FSM(FSM.IDLE), None,
None if not self.neighbor.passive else False,
None if not self.neighbor.passive else False)
self._incoming.opposite = self._outgoing
self._outgoing.opposite = self._incoming
def _reset(self, direction, message='', error=''):
direction.fsm.change(FSM.IDLE)
if not self._restart:
direction.generator = False
direction.proto = None
return
if direction.proto:
direction.proto.close(
u"{0} loop, peer reset, message [{1}] error[{2}]".format(
direction.name, message, error))
direction.proto = None
direction.generator = direction.enabled
self._teardown = None
if direction.name == 'out':
self._delay.increase()
self.neighbor.rib.reset()
# If we are restarting, and the neighbor definition is different, update the neighbor
if self._neighbor:
self.neighbor = self._neighbor
self._neighbor = None
def _stop(self, direction, message):
direction.generator = False
direction.proto.close('%s loop, stop, message [%s]' %
(direction.name, message))
direction.proto = None
# logging
def me(self, message):
return "peer %s ASN %-7s %s" % (self.neighbor.peer_address,
self.neighbor.peer_as, message)
# control
def stop(self):
self._teardown = 3
self._restart = False
self._restarted = False
self._delay.reset()
def resend(self):
self._resend_routes = SEND.NORMAL
self._delay.reset()
def send_new(self, changes=None, update=None):
if changes:
self.neighbor.rib.outgoing.replace(changes)
self._have_routes = self.neighbor.flush if update is None else update
def reestablish(self, restart_neighbor=None):
# we want to tear down the session and re-establish it
self._teardown = 3
self._restart = True
self._restarted = True
self._resend_routes = SEND.NORMAL
self._neighbor = restart_neighbor
self._delay.reset()
def reconfigure(self, restart_neighbor=None):
# we want to update the route which were in the configuration file
self._reconfigure = True
self._neighbor = restart_neighbor
self._resend_routes = SEND.NORMAL
self._neighbor = restart_neighbor
def teardown(self, code, restart=True):
self._restart = restart
self._teardown = code
self._delay.reset()
# sockets we must monitor
def sockets(self):
ios = []
for proto in (self._incoming.proto, self._outgoing.proto):
if proto and proto.connection and proto.connection.io:
ios.append(proto.connection.io)
return ios
def incoming(self, connection):
# if the other side fails, we go back to idle
if self._incoming.proto not in (True, False, None):
self.logger.network('we already have a peer at this address')
return False
# self._incoming.fsm.change(FSM.ACTIVE)
self._incoming.proto = Protocol(self).accept(connection)
# Let's make sure we do some work with this connection
self._incoming.generator = None
return True
def established(self):
return self._incoming.fsm == FSM.ESTABLISHED or self._outgoing.fsm == FSM.ESTABLISHED
def detailed_link_status(self):
state_tbl = {
FSM.IDLE: "Idle",
FSM.ACTIVE: "Active",
FSM.CONNECT: "Connect",
FSM.OPENSENT: "OpenSent",
FSM.OPENCONFIRM: "OpenConfirm",
FSM.ESTABLISHED: "Established"
}
return state_tbl[max(self._incoming.fsm.state,
self._outgoing.fsm.state)]
def negotiated_families(self):
if self._outgoing.proto:
families = [
"%s/%s" % (x[0], x[1])
for x in self._outgoing.proto.negotiated.families
]
else:
families = [
"%s/%s" % (x[0], x[1]) for x in self.neighbor.families()
]
if len(families) > 1:
return "[ %s ]" % " ".join(families)
elif len(families) == 1:
return families[0]
return ''
def _accept(self):
self._incoming.fsm.change(FSM.CONNECT)
# we can do this as Protocol is a mutable object
proto = self._incoming.proto
# send OPEN
message = Message.CODE.NOP
for message in proto.new_open(self._restarted):
if ord(message.TYPE) == Message.CODE.NOP:
yield ACTION.NOW
proto.negotiated.sent(message)
self._incoming.fsm.change(FSM.OPENSENT)
# Read OPEN
wait = environment.settings().bgp.openwait
opentimer = ReceiveTimer(
self.me, wait, 1, 1,
'waited for open too long, we do not like stuck in active')
# Only yield if we have not the open, otherwise the reactor can run the other connection
# which would be bad as we need to do the collission check without going to the other peer
for message in proto.read_open(self.neighbor.peer_address.top()):
opentimer.check_ka(message)
if ord(message.TYPE) == Message.CODE.NOP:
yield ACTION.LATER
self._incoming.fsm.change(FSM.OPENCONFIRM)
proto.negotiated.received(message)
proto.validate_open()
if self._outgoing.fsm == FSM.OPENCONFIRM:
self.logger.network(
'incoming connection finds the outgoing connection is in openconfirm'
)
local_id = self.neighbor.router_id.pack()
remote_id = proto.negotiated.received_open.router_id.pack()
if local_id < remote_id:
self.logger.network('closing the outgoing connection')
self._stop(self._outgoing, 'collision local id < remote id')
yield ACTION.LATER
else:
self.logger.network('aborting the incoming connection')
raise Interrupted(self._incoming)
# Send KEEPALIVE
for message in self._incoming.proto.new_keepalive('OPENCONFIRM'):
yield ACTION.NOW
# Start keeping keepalive timer
self.recv_timer = ReceiveTimer(self.me, proto.negotiated.holdtime, 4,
0)
# Read KEEPALIVE
for message in proto.read_keepalive():
self.recv_timer.check_ka(message)
yield ACTION.NOW
self._incoming.fsm.change(FSM.ESTABLISHED)
# let the caller know that we were sucesfull
yield ACTION.NOW
def _connect(self):
# try to establish the outgoing connection
self._outgoing.fsm.change(FSM.CONNECT)
proto = Protocol(self)
generator = proto.connect()
connected = False
try:
while not connected:
if self._teardown:
raise StopIteration()
connected = six.next(generator)
# we want to come back as soon as possible
yield ACTION.LATER
except StopIteration:
# Connection failed
if not connected:
proto.close('connection to %s:%d failed' %
(self.neighbor.peer_address, proto.port))
# A connection arrived before we could establish !
if not connected or self._incoming.proto:
yield ACTION.NOW
raise Interrupted(self._outgoing)
self._outgoing.proto = proto
# send OPEN
# Only yield if we have not the open, otherwise the reactor can run the other connection
# which would be bad as we need to set the state without going to the other peer
message = Message.CODE.NOP
for message in proto.new_open(self._restarted):
if ord(message.TYPE) == Message.CODE.NOP:
yield ACTION.NOW
proto.negotiated.sent(message)
self._outgoing.fsm.change(FSM.OPENSENT)
# Read OPEN
wait = environment.settings().bgp.openwait
opentimer = ReceiveTimer(
self.me, wait, 1, 1,
'waited for open too long, we do not like stuck in active')
for message in self._outgoing.proto.read_open(
self.neighbor.peer_address.top()):
opentimer.check_ka(message)
# XXX: FIXME: change the whole code to use the ord and not the chr version
# Only yield if we have not the open, otherwise the reactor can run the other connection
# which would be bad as we need to do the collission check
if ord(message.TYPE) == Message.CODE.NOP:
yield ACTION.LATER
self._outgoing.fsm.change(FSM.OPENCONFIRM)
proto.negotiated.received(message)
proto.validate_open()
if self._incoming.fsm == FSM.OPENCONFIRM:
self.logger.network(
'outgoing connection finds the incoming connection is in openconfirm'
)
local_id = self.neighbor.router_id.pack()
remote_id = proto.negotiated.received_open.router_id.pack()
if local_id < remote_id:
self.logger.network('aborting the outgoing connection')
raise Interrupted(self._outgoing)
else:
self.logger.network('closing the incoming connection')
self._stop(self._incoming, 'collision local id < remote id')
yield ACTION.LATER
# Send KEEPALIVE
for message in proto.new_keepalive('OPENCONFIRM'):
yield ACTION.NOW
# Start keeping keepalive timer
self.recv_timer = ReceiveTimer(self.me, proto.negotiated.holdtime, 4,
0)
# Read KEEPALIVE
for message in self._outgoing.proto.read_keepalive():
self.recv_timer.check_ka(message)
yield ACTION.NOW
self._outgoing.fsm.change(FSM.ESTABLISHED)
# let the caller know that we were sucesfull
yield ACTION.NOW
def _main(self, direction):
"""yield True if we want to come back to it asap, None if nothing urgent, and False if stopped"""
if self._teardown:
raise Notify(6, 3)
proto = direction.proto
include_withdraw = False
# Announce to the process BGP is up
self.logger.network('Connected to peer %s (%s)' %
(self.neighbor.name(), direction.name))
if self.neighbor.api['neighbor-changes']:
try:
self.reactor.processes.up(self.neighbor)
except ProcessError:
# Can not find any better error code than 6,0 !
# XXX: We can not restart the program so this will come back again and again - FIX
# XXX: In the main loop we do exit on this kind of error
raise Notify(6, 0, 'ExaBGP Internal error, sorry.')
send_eor = not self.neighbor.manual_eor
new_routes = None
self._resend_routes = SEND.NORMAL
send_families = []
# Every last asm message should be re-announced on restart
for family in self.neighbor.asm:
if family in self.neighbor.families():
self.neighbor.messages.appendleft(self.neighbor.asm[family])
operational = None
refresh = None
command_eor = None
number = 0
refresh_enhanced = True if proto.negotiated.refresh == REFRESH.ENHANCED else False
send_ka = KA(self.me, proto)
while not self._teardown:
for message in proto.read_message():
self.recv_timer.check_ka(message)
if send_ka() is not False:
# we need and will send a keepalive
while send_ka() is None:
yield ACTION.NOW
# Received update
if message.TYPE == Update.TYPE:
number += 1
self.logger.routes(
LazyFormat(
self.me('<< UPDATE (%d)' % number),
message.attributes, lambda _: "%s%s" %
(' attributes' if _ else '', _)))
for nlri in message.nlris:
self.neighbor.rib.incoming.insert_received(
Change(nlri, message.attributes))
self.logger.routes(
LazyFormat(
self.me('<< UPDATE (%d) nlri ' % number), nlri,
str))
elif message.TYPE == RouteRefresh.TYPE:
if message.reserved == RouteRefresh.request:
self._resend_routes = SEND.REFRESH
send_families.append((message.afi, message.safi))
# SEND OPERATIONAL
if self.neighbor.operational:
if not operational:
new_operational = self.neighbor.messages.popleft(
) if self.neighbor.messages else None
if new_operational:
operational = proto.new_operational(
new_operational, proto.negotiated)
if operational:
try:
six.next(operational)
except StopIteration:
operational = None
# make sure that if some operational message are received via the API
# that we do not eat memory for nothing
elif self.neighbor.messages:
self.neighbor.messages.popleft()
# SEND REFRESH
if self.neighbor.route_refresh:
if not refresh:
new_refresh = self.neighbor.refresh.popleft(
) if self.neighbor.refresh else None
if new_refresh:
refresh = proto.new_refresh(new_refresh)
if refresh:
try:
six.next(refresh)
except StopIteration:
refresh = None
# Take the routes already sent to that peer and resend them
if self._reconfigure:
self._reconfigure = False
# we are here following a configuration change
if self._neighbor:
# see what changed in the configuration
self.neighbor.rib.outgoing.replace(
self._neighbor.backup_changes,
self._neighbor.changes)
# do not keep the previous routes in memory as they are not useful anymore
self._neighbor.backup_changes = []
self._have_routes = True
# Take the routes already sent to that peer and resend them
if self._resend_routes != SEND.DONE:
enhanced = True if refresh_enhanced and self._resend_routes == SEND.REFRESH else False
self._resend_routes = SEND.DONE
self.neighbor.rib.outgoing.resend(send_families, enhanced)
self._have_routes = True
send_families = []
# Need to send update
if self._have_routes and not new_routes:
self._have_routes = False
# XXX: in proto really. hum to think about ?
new_routes = proto.new_update(include_withdraw)
if new_routes:
try:
count = 20
while count:
# This can raise a NetworkError
six.next(new_routes)
count -= 1
except StopIteration:
new_routes = None
include_withdraw = True
elif send_eor:
send_eor = False
for _ in proto.new_eors():
yield ACTION.NOW
self.logger.message(self.me('>> EOR(s)'))
# SEND MANUAL KEEPALIVE (only if we have no more routes to send)
elif not command_eor and self.neighbor.eor:
new_eor = self.neighbor.eor.popleft()
command_eor = proto.new_eors(new_eor.afi, new_eor.safi)
if command_eor:
try:
six.next(command_eor)
except StopIteration:
command_eor = None
if new_routes or message.TYPE != NOP.TYPE:
yield ACTION.NOW
elif self.neighbor.messages or operational:
yield ACTION.NOW
elif self.neighbor.eor or command_eor:
yield ACTION.NOW
else:
yield ACTION.LATER
# read_message will loop until new message arrives with NOP
if self._teardown:
break
# If graceful restart, silent shutdown
if self.neighbor.graceful_restart and proto.negotiated.sent_open.capabilities.announced(
Capability.CODE.GRACEFUL_RESTART):
self.logger.network('Closing the session without notification',
'error')
proto.close(
'graceful restarted negotiated, closing without sending any notification'
)
raise NetworkError('closing')
# notify our peer of the shutdown
raise Notify(6, self._teardown)
def _run(self, direction):
"""yield True if we want the reactor to give us back the hand with the same peer loop, None if we do not have any more work to do"""
try:
for action in direction.code():
yield action
for action in self._main(direction):
yield action
# CONNECTION FAILURE
except NetworkError as network:
# we tried to connect once, it failed and it was not a manual request, we stop
if self.once and not self._teardown:
self.logger.network(
'only one attempt to connect is allowed, stopping the peer'
)
self.stop()
self._reset(direction, 'closing connection', network)
return
# NOTIFY THE PEER OF AN ERROR
except Notify as notify:
if direction.proto:
try:
generator = direction.proto.new_notification(notify)
try:
maximum = 20
while maximum:
six.next(generator)
maximum -= 1
yield ACTION.NOW if maximum > 10 else ACTION.LATER
except StopIteration:
pass
except (NetworkError, ProcessError):
self.logger.network(self.me('NOTIFICATION NOT SENT'),
'error')
self._reset(
direction, 'notification sent (%d,%d)' %
(notify.code, notify.subcode), notify)
else:
self._reset(direction)
return
# THE PEER NOTIFIED US OF AN ERROR
except Notification as notification:
# we tried to connect once, it failed and it was not a manual request, we stop
if self.once and not self._teardown:
self.logger.network(
'only one attempt to connect is allowed, stopping the peer'
)
self.stop()
self._reset(direction,'notification received (%d,%d)' \
% (notification.code, notification.subcode), notification)
return
# RECEIVED a Message TYPE we did not expect
except Message as message:
self._reset(direction, 'unexpected message received', message)
return
# PROBLEM WRITING TO OUR FORKED PROCESSES
except ProcessError as process:
self._reset(direction, 'process problem', process)
return
# ....
except Interrupted as interruption:
self._reset(interruption.direction)
return
# UNHANDLED PROBLEMS
except Exception as exc:
# Those messages can not be filtered in purpose
self.logger.raw('\n'.join([
no_panic,
self.me(''), '',
str(type(exc)),
str(exc),
trace(), footer
]))
self._reset(direction)
return
# loop
def run(self):
if self.reactor.processes.broken(self.neighbor):
# XXX: we should perhaps try to restart the process ??
self.logger.processes(
'ExaBGP lost the helper process for this peer - stopping',
'error')
self.stop()
return True
back = ACTION.LATER if self._restart else ACTION.CLOSE
for direction in (self._incoming, self._outgoing):
if direction.generator:
try:
# This generator only stops when it raises
r = six.next(direction.generator)
# if r is ACTION.NOW: status = 'immediately'
# elif r is ACTION.LATER: status = 'next second'
# elif r is ACTION.CLOSE: status = 'stop'
# else: status = 'buggy'
# self.logger.network('%s loop %11s, state is %s' % (direction.name,status,direction.fsm),'debug')
if r == ACTION.NOW:
back = ACTION.NOW
elif r == ACTION.LATER:
back = ACTION.LATER if back != ACTION.NOW else ACTION.NOW
except StopIteration:
# Trying to run a closed loop, no point continuing
direction.generator = direction.enabled
elif direction.generator is None:
if direction.opposite.fsm in [
FSM.OPENCONFIRM, FSM.ESTABLISHED
]:
self.logger.network(
'%s loop, stopping, other one is established' %
direction.name, 'debug')
direction.generator = False
continue
if direction.name == 'out' and self._delay.backoff():
self.logger.network(
'%s loop, skipping, not time yet' % direction.name,
'debug')
back = ACTION.LATER
continue
if self._restart:
self.logger.network(
'%s loop, intialising' % direction.name, 'debug')
direction.generator = self._run(direction)
back = ACTION.LATER # make sure we go through a clean loop
return back