def check_nlri(neighbor, routes):
option.enabled['parser'] = True
announced = _hexa(routes)
negotiated = _negotiated(neighbor)
afi, safi = neighbor.families()[0]
# Is the peer going to send us some Path Information with the route (AddPath)
addpath = negotiated.addpath.send(afi, safi)
nlris = []
try:
while announced:
log.debug('parsing NLRI %s' % announced, 'parser')
nlri, announced = NLRI.unpack_nlri(afi, safi, announced, IN.ANNOUNCED, addpath)
nlris.append(nlri)
except Exception as exc:
log.error('could not parse the nlri', 'parser')
from exabgp.debug import string_exception
log.error(string_exception(exc), 'parser')
if getenv().debug.pdb:
raise
return False
log.debug('', 'parser') # new line
for nlri in nlris:
log.info('nlri json %s' % nlri.json(), 'parser')
return True
def run(self):
if self.reactor.processes.broken(self.neighbor):
# XXX: we should perhaps try to restart the process ??
log.error('ExaBGP lost the helper process for this peer - stopping', 'process')
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 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]:
log.debug('stopping, other connection is established', self.id())
self.generator = False
return ACTION.LATER
if self._delay.backoff():
return ACTION.LATER
if self._restart:
log.debug('initialising connection to %s' % self.id(), 'reactor')
self.generator = self._run()
return ACTION.LATER # make sure we go through a clean loop
return ACTION.CLOSE
def savepid(self):
if not self.pid:
return True
ownid = os.getpid()
flags = os.O_CREAT | os.O_EXCL | os.O_WRONLY
mode = ((os.R_OK | os.W_OK) << 6) | (os.R_OK << 3) | os.R_OK
try:
fd = os.open(self.pid, flags, mode)
except OSError:
try:
pid = open(self.pid, 'r').readline().strip()
if self.check_pid(int(pid)):
log.debug("PIDfile already exists and program still running %s" % self.pid, 'daemon')
return False
else:
# If pid is not running, reopen file without O_EXCL
fd = os.open(self.pid, flags ^ os.O_EXCL, mode)
except (OSError, IOError, ValueError):
log.debug("issue accessing PID file %s (most likely permission or ownership)" % self.pid, 'daemon')
return False
try:
f = os.fdopen(fd, 'w')
line = "%d\n" % ownid
f.write(line)
f.close()
self._saved_pid = True
except IOError:
log.warning("Can not create PIDfile %s" % self.pid, 'daemon')
return False
log.warning("Created PIDfile %s with value %d" % (self.pid, ownid), 'daemon')
return True
def close(self, reason='protocol closed, reason unspecified'):
if self.connection:
log.debug(reason, self.connection.session())
self.peer.stats['down'] = self.peer.stats.get('down', 0) + 1
self.connection.close()
self.connection = None
def _enter(self, name):
location = self.tokeniser.iterate()
log.debug("> %-16s | %s" % (location, self.tokeniser.params()),
'configuration')
if location not in self._structure[name]['sections']:
return self.error.set('section %s is invalid in %s, %s' %
(location, name, self.scope.location()))
self.scope.enter(location)
self.scope.to_context()
class_name = self._structure[name]['sections'][location]
instance = self._structure[class_name].get('class', None)
if not instance:
raise RuntimeError('This should not be happening, debug time !')
if not instance.pre():
return False
if not self.dispatch(self._structure[name]['sections'][location]):
return False
if not instance.post():
return False
left = self.scope.leave()
if not left:
return self.error.set('closing too many parenthesis')
self.scope.to_context()
log.debug("< %-16s | %s" % (left, self.tokeniser.params()),
'configuration')
return True
def listen_on(self, local_addr, remote_addr, port, md5_password,
md5_base64, ttl_in):
try:
if not remote_addr:
remote_addr = IP.create(
'0.0.0.0') if local_addr.ipv4() else IP.create('::')
self._listen(local_addr, remote_addr, port, md5_password,
md5_base64, ttl_in)
log.debug(
'listening for BGP session(s) on %s:%d%s' %
(local_addr, port, ' with MD5' if md5_password else ''),
'network',
)
return True
except NetworkError as exc:
if os.geteuid() != 0 and port <= 1024:
log.critical(
'can not bind to %s:%d, you may need to run ExaBGP as root'
% (local_addr, port), 'network')
else:
log.critical(
'can not bind to %s:%d (%s)' %
(local_addr, port, str(exc)), 'network')
log.critical(
'unset exabgp.tcp.bind if you do not want listen for incoming connections',
'network')
log.critical(
'and check that no other daemon is already binding to port %d'
% port, 'network')
return False
def unpack_nlri(cls, afi, safi, data, action, addpath):
a, s = AFI.create(afi), SAFI.create(safi)
log.debug(LazyNLRI(a, s, addpath, data), 'parser')
key = '%s/%s' % (a, s)
if key in cls.registered_nlri:
return cls.registered_nlri[key].unpack_nlri(a, s, data, action, addpath)
raise Notify(3, 0, 'trying to decode unknown family %s/%s' % (a, s))
def _terminate(self, process_name):
log.debug('terminating process %s' % process_name, 'process')
process = self._process[process_name]
del self._process[process_name]
self._update_fds()
thread = Thread(target=self._terminate_run, args=(process, ))
thread.start()
return thread
def _run(self, name):
command = self.tokeniser.iterate()
log.debug(". %-16s | %s" % (command, self.tokeniser.params()),
'configuration')
if not self.run(name, command):
return False
return True
def new_notification(self, notification):
for _ in self.write(notification):
yield _NOP
log.debug(
'>> NOTIFICATION (%d,%d,"%s")'
% (notification.code, notification.subcode, notification.data.decode('utf-8')),
self.connection.session(),
)
yield notification
def writer(self, data):
if not self.io:
# XXX: FIXME: Make sure it does not hold the cleanup during the closing of the peering session
yield True
return
while not self.writing():
yield False
logfunc.debug(lazyformat('sending TCP payload', data), self.session())
# The first while is here to setup the try/catch block once as it is very expensive
while True:
try:
while True:
if self.defensive and random.randint(0, 2):
raise socket.error(errno.EAGAIN,
'raising network error on purpose')
# we can not use sendall as in case of network buffer filling
# it does raise and does not let you know how much was sent
number = self.io.send(data)
if not number:
self.close()
log.warning(
'%s %s lost TCP connection with peer' %
(self.name(), self.peer), self.session())
raise LostConnection('lost the TCP connection')
data = data[number:]
if not data:
yield True
return
yield False
except socket.error as exc:
if exc.args[0] in error.block:
log.debug(
'%s %s blocking io problem mid-way through writing a message %s, trying to complete'
% (self.name(), self.peer, errstr(exc)),
self.session(),
)
yield False
elif exc.errno == errno.EPIPE:
# The TCP connection is gone.
self.close()
raise NetworkError('Broken TCP connection')
elif exc.args[0] in error.fatal:
self.close()
log.critical(
'%s %s problem sending message (%s)' %
(self.name(), self.peer, errstr(exc)), self.session())
raise NetworkError(
'Problem while writing data to the network (%s)' %
errstr(exc))
# what error could it be !
else:
log.critical(
'%s %s undefined error writing on socket' %
(self.name(), self.peer), self.session())
yield False
def new_keepalive(self, comment=''):
keepalive = KeepAlive()
for _ in self.write(keepalive):
yield _NOP
log.debug('>> KEEPALIVE%s' % (' (%s)' % comment if comment else ''), self.connection.session())
yield keepalive
def _handle_problem(self, process):
if process not in self._process:
return
if self.respawn_number and self._restart[process]:
log.debug('process %s ended, restarting it' % process, 'process')
self._terminate(process)
self._start(process)
else:
log.debug('process %s ended' % process, 'process')
self._terminate(process)
def _reader(self, number):
# The function must not be called if it does not return with no data with a smaller size as parameter
if not self.io:
self.close()
raise NotConnected('Trying to read on a closed TCP connection')
if number == 0:
yield b''
return
while not self.reading():
yield b''
data = b''
reported = ''
while True:
try:
while True:
if self.defensive and random.randint(0, 2):
raise socket.error(errno.EAGAIN, 'raising network error on purpose')
read = self.io.recv(number)
if not read:
self.close()
log.warning('%s %s lost TCP session with peer' % (self.name(), self.peer), self.session())
raise LostConnection('the TCP connection was closed by the remote end')
data += read
number -= len(read)
if not number:
log.debug(LazyFormat('received TCP payload', data), self.session())
yield data
return
yield b''
except socket.timeout as exc:
self.close()
log.warning('%s %s peer is too slow' % (self.name(), self.peer), self.session())
raise TooSlowError('Timeout while reading data from the network (%s)' % errstr(exc))
except socket.error as exc:
if exc.args[0] in error.block:
message = '%s %s blocking io problem mid-way through reading a message %s, trying to complete' % (
self.name(),
self.peer,
errstr(exc),
)
if message != reported:
reported = message
log.debug(message, self.session())
yield b''
elif exc.args[0] in error.fatal:
self.close()
raise LostConnection('issue reading on the socket: %s' % errstr(exc))
# what error could it be !
else:
log.critical('%s %s undefined error reading on socket' % (self.name(), self.peer), self.session())
raise NetworkError('Problem while reading data from the network (%s)' % errstr(exc))
def new_update(self, include_withdraw):
updates = self.neighbor.rib.outgoing.updates(self.neighbor['group-updates'])
number = 0
for update in updates:
for message in update.messages(self.negotiated, include_withdraw):
number += 1
for boolean in self.send(message):
# boolean is a transient network error we already announced
yield _NOP
if number:
log.debug('>> %d UPDATE(s)' % number, self.connection.session())
yield _UPDATE
def read_open(self, ip):
for received_open in self.read_message():
if received_open.TYPE == NOP.TYPE:
yield received_open
else:
break
if received_open.TYPE != Open.TYPE:
raise Notify(5, 1, 'The first packet received is not an open message (%s)' % received_open)
log.debug('<< %s' % received_open, self.connection.session())
yield received_open
def removepid(self):
if not self.pid or not self._saved_pid:
return
try:
os.remove(self.pid)
except OSError as exc:
if exc.errno == errno.ENOENT:
pass
else:
log.error("Can not remove PIDfile %s" % self.pid, 'daemon')
return
log.debug("Removed PIDfile %s" % self.pid, 'daemon')
def __init__(self, afi, peer, local, io):
Connection.__init__(self, afi, peer, local)
log.debug('connection from %s' % self.peer, 'network')
try:
self.io = io
asynchronous(self.io, self.peer)
nagle(self.io, self.peer)
self.success()
except NetworkError as exc:
self.close()
raise NotConnected(errstr(exc))
def _terminate_run(self, process, process_name):
try:
process.terminate()
try:
process.wait(timeout=2)
except subprocess.TimeoutExpired:
log.debug('force kill unresponsive %s' % process_name,
'process')
process.kill()
process.wait(timeout=1)
except (OSError, KeyError, subprocess.TimeoutExpired):
# the process is most likely already dead
pass
def close(self, reason='protocol closed, reason unspecified'):
if self.connection:
log.debug(reason, self.connection.session())
# must be first otherwise we could have a loop caused by the raise in the below
self.connection.close()
self.connection = None
self.peer.stats['down'] = self.peer.stats.get('down', 0) + 1
try:
if self.peer.neighbor.api['neighbor-changes']:
self.peer.reactor.processes.down(self.peer.neighbor, reason)
except ProcessError:
log.debug('could not send notification of neighbor close to API', self.connection.session())
def check_ka_timer(self, message=_NOP, ignore=_NOP.TYPE):
if self.holdtime == 0:
return message.TYPE != KeepAlive.TYPE
now = int(time.time())
if message.TYPE != ignore:
self.last_read = now
elapsed = now - self.last_read
if elapsed > self.holdtime:
raise Notify(self.code, self.subcode, self.message)
if self.last_print != now:
left = self.holdtime - elapsed
log.debug('receive-timer %d second(s) left' % left,
source='ka-' + self.session())
self.last_print = now
return True
def restart(self):
"""Kill the BGP session and restart it"""
log.info('performing restart of exabgp %s' % version, 'reactor')
# XXX: FIXME: Could return False, in case there is interference with old config...
reloaded = self.configuration.reload()
for key in self._peers.keys():
if key not in self.configuration.neighbors.keys():
peer = self._peers[key]
log.debug('removing peer %s' % peer.neighbor.name(), 'reactor')
self._peers[key].remove()
else:
self._peers[key].reestablish()
self.processes.start(self.configuration.processes, True)
def cmdline(cmdarg):
env = getenv()
# Must be done before setting the logger as it modify its behaviour
if cmdarg.verbose:
env.log.all = True
env.log.level = syslog.LOG_DEBUG
log.init()
if cmdarg.pdb:
env.debug.pdb = True
if cmdarg.verbose:
env.log.parser = True
for configuration in cmdarg.configuration:
log.notice(f'loading {configuration}', 'configuration')
location = getconf(configuration)
if not location:
log.critical(f'{configuration} is not an exabgp config file',
'configuration')
sys.exit(1)
config = Reactor([location]).configuration
if not config.reload():
log.critical(f'{configuration} is not a valid config file',
'configuration')
sys.exit(1)
log.info(f'\u2713 loading', 'configuration')
if cmdarg.neighbor:
log.notice(f'checking neighbors', 'configuration')
for name, neighbor in config.neighbors.items():
reparsed = neighbor.string()
for line in reparsed.split('\n'):
log.debug(line, configuration)
log.info(f'\u2713 neighbor {name.split()[1]}',
'configuration')
if cmdarg.route:
log.notice(f'checking routes', 'configuration')
if not check_generation(config.neighbors):
log.critical(f'{configuration} has an invalid route',
'configuration')
sys.exit(1)
log.info(f'\u2713 routes', 'configuration')
def need_ka(self):
if not self.keepalive:
return False
now = int(time.time())
left = self.last_sent + self.keepalive - now
if now != self.last_print:
log.debug('send-timer %d second(s) left' % left,
source='ka-' + self.session())
self.last_print = now
if left <= 0:
self.last_sent = now
return True
return False
def check_update(neighbor, raw):
option.enabled['parser'] = True
negotiated = _negotiated(neighbor)
while raw:
if raw.startswith(b'\xff' * 16):
kind = raw[18]
size = (raw[16] << 16) + raw[17]
injected, raw = raw[19:size], raw[size:]
if kind == 2:
log.debug('the message is an update', 'parser')
decoding = 'update'
else:
log.debug(
'the message is not an update (%d) - aborting' % kind,
'parser')
return False
else:
log.debug('header missing, assuming this message is ONE update',
'parser')
decoding = 'update'
injected, raw = raw, ''
try:
# This does not take the BGP header - let's assume we will not break that :)
update = Update.unpack_message(injected, Direction.IN, negotiated)
except Notify:
import traceback
log.error('could not parse the message', 'parser')
log.error(traceback.format_exc(), 'parser')
if getenv().debug.pdb:
raise
return False
except Exception:
import traceback
log.error('could not parse the message', 'parser')
log.error(traceback.format_exc(), 'parser')
if getenv().debug.pdb:
raise
return False
log.debug('', 'parser') # new line
for number in range(len(update.nlris)):
change = Change(update.nlris[number], update.attributes)
log.info(
'decoded %s %s %s' %
(decoding, change.nlri.action, change.extensive()), 'parser')
log.info(
'update json %s' % Response.JSON(json_version).update(
neighbor, 'in', update, None, '', ''), 'parser')
return True
def terminate(self):
for process in list(self._process):
if not self.silence:
try:
self.write(process, self._encoder[process].shutdown())
except ProcessError:
pass
self.silence = True
# waiting a little to make sure IO is flushed to the pipes
# we are using unbuffered IO but still ..
time.sleep(0.1)
for process in list(self._process):
try:
t = self._terminate(process)
t.join()
except OSError:
# we most likely received a SIGTERM signal and our child is already dead
log.debug('child process %s was already dead' % process,
'process')
self.clean()
def partial(self, section, text, action='announce'):
self._cleanup(
) # this perform a big cleanup (may be able to be smarter)
self._clear()
self.tokeniser.set_api(
text if text.endswith(';') or text.endswith('}') else text + ' ;')
self.tokeniser.set_action(action)
if self.parseSection(section) is not True:
self._rollback_reload()
log.debug(
"\n"
"syntax error in api command %s\n"
"line %d: %s\n"
"\n%s" % (self.scope.location(), self.tokeniser.number,
' '.join(self.tokeniser.line), str(self.error)),
'configuration',
)
return False
return True
def handle_connection(self, connection):
log.debug("state machine for the peer is %s" % self.fsm.name(),
self.id())
# if the other side fails, we go back to idle
if self.fsm == FSM.ESTABLISHED:
log.debug(
'we already have a peer in state established for %s' %
connection.name(), self.id())
return connection.notification(
6, 7, '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:
log.debug(
'closing incoming connection as we have an outgoing connection with higher router-id for %s'
% connection.name(),
self.id(),
)
return connection.notification(
6,
7,
'could not accept the connection, as another connection is already in open-confirm and will go through',
)
# accept the connection
if self.proto:
log.debug(
'closing outgoing connection as we have another incoming on with higher router-id for %s'
% connection.name(),
self.id(),
)
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 write(self, process, string, neighbor=None):
if string is None:
return True
# XXX: FIXME: This is potentially blocking
while True:
try:
self._process[process].stdin.write(
bytes('%s\n' % string, 'ascii'))
except IOError as exc:
self._broken.append(process)
if exc.errno == errno.EPIPE:
self._broken.append(process)
log.debug('issue while sending data to our helper program',
'process')
raise ProcessError()
else:
# Could it have been caused by a signal ? What to do.
log.debug(
'error received while sending data to helper program, retrying (%s)'
% errstr(exc), 'process')
continue
break
try:
self._process[process].stdin.flush()
except IOError as exc:
# AFAIK, the buffer should be flushed at the next attempt.
log.debug(
'error received while FLUSHING data to helper program, retrying (%s)'
% errstr(exc), 'process')
return True
def establish(self):
last = time.time() - 2.0
while True:
notify = time.time() - last > 1.0
if notify:
last = time.time()
if notify:
log.debug('attempting connection to %s:%d' % (self.peer, self.port), self.session())
connect_issue = self._connect()
if connect_issue:
if notify:
log.debug('connection to %s:%d failed' % (self.peer, self.port), self.session())
log.debug(str(connect_issue), self.session())
yield False
continue
connected = False
for r, message in ready(self.io):
if not r:
yield False
continue
connected = True
if connected:
self.success()
if not self.local:
self.local = self.io.getsockname()[0]
yield True
return
self._setup()
