# -*- python -*-
-import hippotat.slip as slip
+import signal
+signal.signal(signal.SIGINT, signal.SIG_DFL)
+
+import sys
+
+import twisted
+from twisted.internet import reactor
+from twisted.logger import LogLevel
+import twisted.internet.endpoints
import ipaddress
from ipaddress import AddressValueError
+from optparse import OptionParser
+from configparser import ConfigParser
+from configparser import NoOptionError
+
+import collections
+
+import re as regexp
+
+import hippotat.slip as slip
+
+defcfg = '''
+[DEFAULT]
+#[<client>] overrides
+max_batch_down = 65536 # used by server, subject to [limits]
+max_queue_time = 10 # used by server, subject to [limits]
+max_request_time = 54 # used by server, subject to [limits]
+target_requests_outstanding = 3 # must match; subject to [limits] on server
+max_requests_outstanding = 4 # used by client
+max_batch_up = 4000 # used by client
+http_timeout = 30 # used by client
+
+#[server] or [<client>] overrides
+ipif = userv root ipif %(local)s,%(peer)s,%(mtu)s,slip %(rnets)s
+# extra interpolations: %(local)s %(peer)s %(rnet)s
+# obtained on server [virtual]server [virtual]relay [virtual]network
+# from on client <client> [virtual]server [virtual]routes
+
+[virtual]
+mtu = 1500
+routes = ''
+# network = <prefix>/<len> # mandatory for server
+# server = <ipaddr> # used by both, default is computed from `network'
+# relay = <ipaddr> # used by server, default from `network' and `server'
+# default server is first host in network
+# default relay is first host which is not server
+
+[server]
+# addrs = 127.0.0.1 ::1 # mandatory for server
+port = 80 # used by server
+# url # used by client; default from first `addrs' and `port'
+
+# [<client-ip4-or-ipv6-address>]
+# password = <password> # used by both, must match
+
+[limits]
+max_batch_down = 262144 # used by server
+max_queue_time = 121 # used by server
+max_request_time = 121 # used by server
+target_requests_outstanding = 10 # used by server
+'''
+
+# these need to be defined here so that they can be imported by import *
+cfg = ConfigParser()
+optparser = OptionParser()
+
+_mimetrans = str.maketrans(b'-'+slip.esc, slip.esc+'-')
+def mime_translate(s):
+ # SLIP-encoded packets cannot contain ESC ESC.
+ # Swap `-' and ESC. The result cannot contain `--'
+ return s.translate(_mimetrans)
+
+class ConfigResults:
+ def __init__(self, d = { }):
+ self.__dict__ = d
+ def __repr__(self):
+ return 'ConfigResults('+repr(self.__dict__)+')'
+
+c = ConfigResults()
+
+def log_discard(packet, saddr, daddr, why):
+ print('DROP ', saddr, daddr, why)
+# syslog.syslog(syslog.LOG_DEBUG,
+# 'discarded packet %s -> %s (%s)' % (saddr, daddr, why))
+
#---------- packet parsing ----------
def packet_addrs(packet):
except NetworkValueError:
r = ipaddress.IPv6Network(input)
return r
+
+#---------- ipif (SLIP) subprocess ----------
+
+class SlipStreamDecoder():
+ def __init__(self, on_packet):
+ # we will call packet(<packet>)
+ self._buffer = b''
+ self._on_packet = on_packet
+
+ def inputdata(self, data):
+ #print('SLIP-GOT ', repr(data))
+ self._buffer += data
+ packets = slip.decode(self._buffer)
+ self._buffer = packets.pop()
+ for packet in packets:
+ self._maybe_packet(packet)
+
+ def _maybe_packet(self, packet):
+ if len(packet):
+ self._on_packet(packet)
+
+ def flush(self):
+ self._maybe_packet(self._buffer)
+ self._buffer = b''
+
+class _IpifProcessProtocol(SlipProtocol):
+ def __init__(self, router):
+ self._router = router
+ self._decoder = SlipStreamDecoder(self.slip_on_packet)
+ def connectionMade(self): pass
+ def outReceived(self, data):
+ self._decoder.inputdata(data)
+ def slip_on_packet(self, packet):
+ (saddr, daddr) = packet_addrs(packet)
+ if saddr.is_link_local or daddr.is_link_local:
+ log_discard(packet, saddr, daddr, 'link-local')
+ return
+ self._router(packet, saddr, daddr)
+ def processEnded(self, status):
+ status.raiseException()
+
+def start_ipif(command, router):
+ global ipif
+ ipif = _IpifProcessProtocol(router)
+ reactor.spawnProcess(ipif,
+ '/bin/sh',['sh','-xc', command],
+ childFDs={0:'w', 1:'r', 2:2})
+
+def queue_inbound(packet):
+ ipif.transport.write(slip.delimiter)
+ ipif.transport.write(slip.encode(packet))
+ ipif.transport.write(slip.delimiter)
+
+#---------- packet queue ----------
+
+class PacketQueue():
+ def __init__(self, max_queue_time):
+ self._max_queue_time = max_queue_time
+ self._pq = collections.deque() # packets
+
+ def append(self, packet):
+ self._pq.append((time.monotonic(), packet))
+
+ def nonempty(self):
+ while True:
+ try: (queuetime, packet) = self._pq[0]
+ except IndexError: return False
+
+ age = time.monotonic() - queuetime
+ if age > self.max_queue_time:
+ # strip old packets off the front
+ self._pq.popleft()
+ continue
+
+ return True
+
+ def process(self, sizequery, moredata, max_batch):
+ # sizequery() should return size of batch so far
+ # moredata(s) should add s to batch
+ while True:
+ try: (dummy, packet) = self._pq[0]
+ except IndexError: break
+
+ encoded = slip.encode(packet)
+ sofar = sizequery()
+
+ if sofar > 0:
+ if sofar + len(slip.delimiter) + len(encoded) > max_batch:
+ break
+ moredata(slip.delimiter)
+
+ moredata(encoded)
+ self._pq.popLeft()
+
+#---------- error handling ----------
+
+def crash(err):
+ print('CRASH ', err, file=sys.stderr)
+ try: reactor.stop()
+ except twisted.internet.error.ReactorNotRunning: pass
+
+def crash_on_defer(defer):
+ defer.addErrback(lambda err: crash(err))
+
+vdef crash_on_critical(event):
+ if event.get('log_level') >= LogLevel.critical:
+ crash(twisted.logger.formatEvent(event))
+
+#---------- config processing ----------
+
+def process_cfg_common_always():
+ global mtu
+ c.mtu = cfg.get('virtual','mtu')
+
+def process_cfg_ipif(section, varmap):
+ for d, s in varmap:
+ try: v = getattr(c, s)
+ except AttributeError: continue
+ setattr(c, d, v)
+
+ print(repr(c))
+
+ c.ipif_command = cfg.get(section,'ipif', vars=c.__dict__)
+
+def process_cfg_network():
+ c.network = ipnetwork(cfg.get('virtual','network'))
+ if c.network.num_addresses < 3 + 2:
+ raise ValueError('network needs at least 2^3 addresses')
+
+def process_cfg_server():
+ try:
+ c.server = cfg.get('virtual','server')
+ except NoOptionError:
+ process_cfg_network()
+ c.server = next(c.network.hosts())
+
+class ServerAddr():
+ def __init__(self, port, addrspec):
+ self.port = port
+ # also self.addr
+ try:
+ self.addr = ipaddress.IPv4Address(addrspec)
+ self._endpointfactory = twisted.internet.endpoints.TCP4ServerEndpoint
+ self._inurl = '%s'
+ except AddressValueError:
+ self.addr = ipaddress.IPv6Address(addrspec)
+ self._endpointfactory = twisted.internet.endpoints.TCP6ServerEndpoint
+ self._inurl = '[%s]'
+ def make_endpoint(self):
+ return self._endpointfactory(reactor, self.port, self.addr)
+ def url(self):
+ url = 'http://' + (self._inurl % self.addr)
+ if self.port != 80: url += ':%d' % self.port
+ url += '/'
+ return url
+
+def process_cfg_saddrs():
+ try: port = cfg.getint('server','port')
+ except NoOptionError: port = 80
+
+ c.saddrs = [ ]
+ for addrspec in cfg.get('server','addrs').split():
+ sa = ServerAddr(port, addrspec)
+ c.saddrs.append(sa)
+
+def process_cfg_clients(constructor):
+ c.clients = [ ]
+ for cs in cfg.sections():
+ if not (':' in cs or '.' in cs): continue
+ ci = ipaddr(cs)
+ pw = cfg.get(cs, 'password')
+ constructor(ci,cs,pw)
+
+#---------- startup ----------
+
+def common_startup():
+ twisted.logger.globalLogPublisher.addObserver(crash_on_critical)
+
+ optparser.add_option('-c', '--config', dest='configfile',
+ default='/etc/hippotat/config')
+ (opts, args) = optparser.parse_args()
+ if len(args): optparser.error('no non-option arguments please')
+
+ re = regexp.compile('#.*')
+ cfg.read_string(re.sub('', defcfg))
+ cfg.read(opts.configfile)
+
+def common_run():
+ reactor.run()
+ print('CRASHED (end)', file=sys.stderr)
~ian / hippotat.git / blobdiff