3 # Hippotat - Asinine IP Over HTTP program
4 # hippotatlib/__init__.py - common library code
6 # Copyright 2017 Ian Jackson
10 # This program is free software: you can redistribute it and/or modify
11 # it under the terms of the GNU General Public License as published by
12 # the Free Software Foundation, either version 3 of the License, or
13 # (at your option) any later version.
15 # This program is distributed in the hope that it will be useful,
16 # but WITHOUT ANY WARRANTY; without even the implied warranty of
17 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 # GNU General Public License for more details.
20 # You should have received a copy of the GNU General Public License
21 # along with this program, in the file GPLv3. If not,
22 # see <http://www.gnu.org/licenses/>.
26 signal.signal(signal.SIGINT, signal.SIG_DFL)
31 from zope.interface import implementer
34 from twisted.internet import reactor
35 import twisted.internet.endpoints
37 from twisted.logger import LogLevel
38 import twisted.python.constants
39 from twisted.python.constants import NamedConstant
42 from ipaddress import AddressValueError
44 from optparse import OptionParser
46 from configparser import ConfigParser
47 from configparser import NoOptionError
49 from functools import partial
58 import hippotatlib.slip as slip
60 class DBG(twisted.python.constants.Names):
61 INIT = NamedConstant()
62 CONFIG = NamedConstant()
63 ROUTE = NamedConstant()
64 DROP = NamedConstant()
65 OWNSOURCE = NamedConstant()
66 FLOW = NamedConstant()
67 HTTP = NamedConstant()
68 TWISTED = NamedConstant()
69 QUEUE = NamedConstant()
70 HTTP_CTRL = NamedConstant()
71 QUEUE_CTRL = NamedConstant()
72 HTTP_FULL = NamedConstant()
73 CTRL_DUMP = NamedConstant()
74 SLIP_FULL = NamedConstant()
75 DATA_COMPLETE = NamedConstant()
77 _hex_codec = codecs.getencoder('hex_codec')
79 #---------- logging ----------
81 org_stderr = sys.stderr
83 log = twisted.logger.Logger()
86 debug_def_detail = DBG.HTTP
88 def log_debug(dflag, msg, idof=None, d=None):
89 if dflag not in debug_set: return
90 #print('---------------->',repr((dflag, msg, idof, d)), file=sys.stderr)
92 msg = '[%#x] %s' % (id(idof), msg)
95 if not DBG.DATA_COMPLETE in debug_set:
99 d = _hex_codec(d)[0].decode('ascii')
100 msg += ' ' + d + trunc
101 log.info('{dflag} {msgcore}', dflag=dflag, msgcore=msg)
103 def logevent_is_boringtwisted(event):
105 if event.get('log_level') != LogLevel.info:
107 dflag = event.get('dflag')
108 if dflag is False : return False
109 if dflag in debug_set: return False
110 if dflag is None and DBG.TWISTED in debug_set: return False
113 print('EXCEPTION (IN BORINGTWISTED CHECK)',
114 traceback.format_exc(), file=org_stderr)
117 @implementer(twisted.logger.ILogFilterPredicate)
118 class LogNotBoringTwisted:
119 def __call__(self, event):
121 twisted.logger.PredicateResult.no
122 if logevent_is_boringtwisted(event) else
123 twisted.logger.PredicateResult.yes
126 #---------- default config ----------
130 max_batch_down = 65536
132 target_requests_outstanding = 3
134 http_timeout_grace = 5
135 max_requests_outstanding = 6
140 ifname_client = hippo%%d
141 ifname_server = shippo%%d
143 #[server] or [<client>] overrides
144 ipif = userv root ipif %(local)s,%(peer)s,%(mtu)s,slip,%(ifname)s %(rnets)s
146 # relating to virtual network
149 # addrs = 127.0.0.1 ::1
152 # relating to virtual network
153 vvnetwork = 172.24.230.192
154 # vnetwork = <prefix>/<len>
159 # [<client-ip4-or-ipv6-address>]
160 # password = <password> # used by both, must match
163 max_batch_down = 262144
166 target_requests_outstanding = 10
169 # these need to be defined here so that they can be imported by import *
170 cfg = ConfigParser(strict=False)
171 optparser = OptionParser()
173 _mimetrans = bytes.maketrans(b'-'+slip.esc, slip.esc+b'-')
174 def mime_translate(s):
175 # SLIP-encoded packets cannot contain ESC ESC.
176 # Swap `-' and ESC. The result cannot contain `--'
177 return s.translate(_mimetrans)
183 return 'ConfigResults('+repr(self.__dict__)+')'
185 def log_discard(packet, iface, saddr, daddr, why):
187 'discarded packet [%s] %s -> %s: %s' % (iface, saddr, daddr, why),
190 #---------- packet parsing ----------
192 def packet_addrs(packet):
193 version = packet[0] >> 4
197 factory = ipaddress.IPv4Address
201 factory = ipaddress.IPv6Address
203 raise ValueError('unsupported IP version %d' % version)
204 saddr = factory(packet[ saddroff : saddroff + addrlen ])
205 daddr = factory(packet[ saddroff + addrlen : saddroff + addrlen*2 ])
206 return (saddr, daddr)
208 #---------- address handling ----------
212 r = ipaddress.IPv4Address(input)
213 except AddressValueError:
214 r = ipaddress.IPv6Address(input)
217 def ipnetwork(input):
219 r = ipaddress.IPv4Network(input)
220 except NetworkValueError:
221 r = ipaddress.IPv6Network(input)
224 #---------- ipif (SLIP) subprocess ----------
226 class SlipStreamDecoder():
227 def __init__(self, desc, on_packet):
229 self._on_packet = on_packet
231 self._log('__init__')
233 def _log(self, msg, **kwargs):
234 log_debug(DBG.SLIP_FULL, 'slip %s: %s' % (self._desc, msg), **kwargs)
236 def inputdata(self, data):
237 self._log('inputdata', d=data)
238 data = self._buffer + data
240 packets = slip.decode(data, True)
241 self._buffer = packets.pop()
242 for packet in packets:
243 self._maybe_packet(packet)
244 self._log('bufremain', d=self._buffer)
246 def _maybe_packet(self, packet):
247 self._log('maybepacket', d=packet)
249 self._on_packet(packet)
255 packets = slip.decode(data)
256 assert(len(packets) == 1)
257 self._maybe_packet(packets[0])
259 class _IpifProcessProtocol(twisted.internet.protocol.ProcessProtocol):
260 def __init__(self, router):
261 self._router = router
262 self._decoder = SlipStreamDecoder('ipif', self.slip_on_packet)
263 def connectionMade(self): pass
264 def outReceived(self, data):
265 self._decoder.inputdata(data)
266 def slip_on_packet(self, packet):
267 (saddr, daddr) = packet_addrs(packet)
268 if saddr.is_link_local or daddr.is_link_local:
269 log_discard(packet, 'ipif', saddr, daddr, 'link-local')
271 self._router(packet, saddr, daddr)
272 def processEnded(self, status):
273 status.raiseException()
275 def start_ipif(command, router):
276 ipif = _IpifProcessProtocol(router)
277 reactor.spawnProcess(ipif,
278 '/bin/sh',['sh','-xc', command],
279 childFDs={0:'w', 1:'r', 2:2},
283 def queue_inbound(ipif, packet):
284 log_debug(DBG.FLOW, "queue_inbound", d=packet)
285 ipif.transport.write(slip.delimiter)
286 ipif.transport.write(slip.encode(packet))
287 ipif.transport.write(slip.delimiter)
289 #---------- packet queue ----------
292 def __init__(self, desc, max_queue_time):
295 self._max_queue_time = max_queue_time
296 self._pq = collections.deque() # packets
298 def _log(self, dflag, msg, **kwargs):
299 log_debug(dflag, self._desc+' pq: '+msg, **kwargs)
301 def append(self, packet):
302 self._log(DBG.QUEUE, 'append', d=packet)
303 self._pq.append((time.monotonic(), packet))
306 self._log(DBG.QUEUE, 'nonempty ?')
308 try: (queuetime, packet) = self._pq[0]
310 self._log(DBG.QUEUE, 'nonempty ? empty.')
313 age = time.monotonic() - queuetime
314 if age > self._max_queue_time:
315 # strip old packets off the front
316 self._log(DBG.QUEUE, 'dropping (old)', d=packet)
320 self._log(DBG.QUEUE, 'nonempty ? nonempty.')
323 def process(self, sizequery, moredata, max_batch):
324 # sizequery() should return size of batch so far
325 # moredata(s) should add s to batch
326 self._log(DBG.QUEUE, 'process...')
328 try: (dummy, packet) = self._pq[0]
330 self._log(DBG.QUEUE, 'process... empty')
333 self._log(DBG.QUEUE_CTRL, 'process... packet', d=packet)
335 encoded = slip.encode(packet)
338 self._log(DBG.QUEUE_CTRL,
339 'process... (sofar=%d, max=%d) encoded' % (sofar, max_batch),
343 if sofar + len(slip.delimiter) + len(encoded) > max_batch:
344 self._log(DBG.QUEUE_CTRL, 'process... overflow')
346 moredata(slip.delimiter)
351 #---------- error handling ----------
358 print('========== CRASH ==========', err,
359 '===========================', file=sys.stderr)
361 except twisted.internet.error.ReactorNotRunning: pass
363 def crash_on_defer(defer):
364 defer.addErrback(lambda err: crash(err))
366 def crash_on_critical(event):
367 if event.get('log_level') >= LogLevel.critical:
368 crash(twisted.logger.formatEvent(event))
370 #---------- config processing ----------
372 def _cfg_process_putatives():
375 # maps from abstract object to canonical name for cs's
377 def putative(cmap, abstract, canoncs):
379 current_canoncs = cmap[abstract]
383 assert(current_canoncs == canoncs)
384 cmap[abstract] = canoncs
386 server_pat = r'[-.0-9A-Za-z]+'
387 client_pat = r'[.:0-9a-f]+'
388 server_re = regexp.compile(server_pat)
389 serverclient_re = regexp.compile(
390 server_pat + r' ' + '(?:' + client_pat + '|LIMIT)')
392 for cs in cfg.sections():
394 print('warning: ignoring config section [%s] (%s)' % (cs, why),
397 if cs == 'LIMIT' or cs == 'COMMON':
398 # plan A "[LIMIT]" or "[COMMON]"
402 # plan B "[<client>]" part 1
404 except AddressValueError:
406 if server_re.fullmatch(cs):
407 # plan C "[<servername>]"
408 putative(servers, cs, cs)
411 if serverclient_re.fullmatch(cs):
412 # plan D "[<servername> <client>]" part 1
413 (pss,pcs) = cs.split(' ')
416 # plan E "[<servername> LIMIT]"
420 # plan D "[<servername> <client>]" part 2
422 except AddressValueError:
423 # plan F "[<some thing we do not understand>]"
424 log_ignore('bad-addr')
427 else: # no AddressValueError
428 # plan D "[<servername> <client]" part 3
429 putative(clients, ci, pcs)
430 putative(servers, pss, pss)
433 else: # no AddressValueError
434 # plan B "[<client>" part 2
435 putative(clients, ci, cs)
438 return (servers, clients)
440 def cfg_process_general(c, ss):
441 c.mtu = cfg1getint(ss, 'mtu')
443 def cfg_process_saddrs(c, ss):
445 def __init__(self, port, addrspec):
449 self.addr = ipaddress.IPv4Address(addrspec)
450 self._endpointfactory = twisted.internet.endpoints.TCP4ServerEndpoint
452 except AddressValueError:
453 self.addr = ipaddress.IPv6Address(addrspec)
454 self._endpointfactory = twisted.internet.endpoints.TCP6ServerEndpoint
455 self._inurl = b'[%s]'
456 def make_endpoint(self):
457 return self._endpointfactory(reactor, self.port,
458 interface= '%s' % self.addr)
460 url = b'http://' + (self._inurl % str(self.addr).encode('ascii'))
461 if self.port != 80: url += b':%d' % self.port
465 return 'ServerAddr'+repr((self.port,self.addr))
467 c.port = cfg1getint(ss,'port')
469 for addrspec in cfg1get(ss, 'addrs').split():
470 sa = ServerAddr(c.port, addrspec)
473 def cfg_process_vnetwork(c, ss):
474 c.vnetwork = ipnetwork(cfg1get(ss,'vnetwork'))
475 if c.vnetwork.num_addresses < 3 + 2:
476 raise ValueError('vnetwork needs at least 2^3 addresses')
478 def cfg_process_vaddr(c, ss):
480 c.vaddr = cfg1get(ss,'vaddr')
481 except NoOptionError:
482 cfg_process_vnetwork(c, ss)
483 c.vaddr = next(c.vnetwork.hosts())
485 def cfg_search_section(key,sections):
486 for section in sections:
487 if cfg.has_option(section, key):
489 raise NoOptionError(key, repr(sections))
491 def cfg_get_raw(*args, **kwargs):
492 # for passing to cfg_search
493 return cfg.get(*args, raw=True, **kwargs)
495 def cfg_search(getter,key,sections):
496 section = cfg_search_section(key,sections)
497 return getter(section, key)
499 def cfg1get(section,key, getter=cfg.get,**kwargs):
500 section = cfg_search_section(key,[section,'COMMON'])
501 return getter(section,key,**kwargs)
503 def cfg1getint(section,key, **kwargs):
504 return cfg1get(section,key, getter=cfg.getint,**kwargs);
506 def cfg_process_client_limited(cc,ss,sections,key):
507 val = cfg_search(cfg1getint, key, sections)
508 lim = cfg_search(cfg1getint, key, ['%s LIMIT' % ss, 'LIMIT'])
509 cc.__dict__[key] = min(val,lim)
511 def cfg_process_client_common(cc,ss,cs,ci):
512 # returns sections to search in, iff password is defined, otherwise None
515 sections = ['%s %s' % (ss,cs),
520 try: pwsection = cfg_search_section('password', sections)
521 except NoOptionError: return None
523 pw = cfg1get(pwsection, 'password')
524 cc.password = pw.encode('utf-8')
526 cfg_process_client_limited(cc,ss,sections,'target_requests_outstanding')
527 cfg_process_client_limited(cc,ss,sections,'http_timeout')
531 def cfg_process_ipif(c, sections, varmap):
533 try: v = getattr(c, s)
534 except AttributeError: continue
537 #print('CFGIPIF',repr((varmap, sections, c.__dict__)),file=sys.stderr)
539 section = cfg_search_section('ipif', sections)
540 c.ipif_command = cfg1get(section,'ipif', vars=c.__dict__)
542 #---------- startup ----------
544 def log_debug_config(m):
545 if not DBG.CONFIG in debug_set: return
546 print('DBG.CONFIG:', m)
548 def common_startup(process_cfg):
549 # calls process_cfg(putative_clients, putative_servers)
551 # ConfigParser hates #-comments after values
552 trailingcomments_re = regexp.compile(r'#.*')
553 cfg.read_string(trailingcomments_re.sub('', defcfg))
556 def readconfig(pathname, mandatory=True):
557 def log(m, p=pathname):
558 if not DBG.CONFIG in debug_set: return
559 log_debug_config('%s: %s' % (m, p))
562 files = os.listdir(pathname)
564 except FileNotFoundError:
569 except NotADirectoryError:
576 re = regexp.compile('[^-A-Za-z0-9_]')
577 for f in os.listdir(pathname):
578 if re.search(f): continue
579 subpath = pathname + '/' + f
582 except FileNotFoundError:
583 log('entry skipped', subpath)
586 log('entry read', subpath)
588 def oc_config(od,os, value, op):
593 def oc_extra_config(od,os, value, op):
596 def read_defconfig():
597 readconfig('/etc/hippotat/config.d', False)
598 readconfig('/etc/hippotat/passwords.d', False)
599 readconfig('/etc/hippotat/master.cfg', False)
601 def oc_defconfig(od,os, value, op):
604 read_defconfig(value)
606 def dfs_less_detailed(dl):
607 return [df for df in DBG.iterconstants() if df <= dl]
609 def ds_default(od,os,dl,op):
612 debug_set |= set(dfs_less_detailed(debug_def_detail))
614 def ds_select(od,os, spec, op):
615 for it in spec.split(','):
617 if it.startswith('-'):
618 mutator = debug_set.discard
621 mutator = debug_set.add
624 dfs = DBG.iterconstants()
628 mapper = dfs_less_detailed
631 mapper = lambda x: [x]
634 dfspec = DBG.lookupByName(it)
636 optparser.error('unknown debug flag %s in --debug-select' % it)
643 optparser.add_option('-D', '--debug',
646 help='enable default debug (to stdout)',
647 callback= ds_default)
649 optparser.add_option('--debug-select',
652 metavar='[-]DFLAG[+]|[-]+,...',
654 '''enable (`-': disable) each specified DFLAG;
655 `+': do same for all "more interesting" DFLAGSs;
656 just `+': all DFLAGs.
657 DFLAGS: ''' + ' '.join([df.name for df in DBG.iterconstants()]),
661 optparser.add_option('-c', '--config',
664 metavar='CONFIGFILE',
669 optparser.add_option('--extra-config',
672 metavar='CONFIGFILE',
675 callback= oc_extra_config)
677 optparser.add_option('--default-config',
679 callback= oc_defconfig)
681 (opts, args) = optparser.parse_args()
682 if len(args): optparser.error('no non-option arguments please')
688 (pss, pcs) = _cfg_process_putatives()
689 process_cfg(opts, pss, pcs)
690 except (configparser.Error, ValueError):
691 traceback.print_exc(file=sys.stderr)
692 print('\nInvalid configuration, giving up.', file=sys.stderr)
696 #print('X', debug_set, file=sys.stderr)
698 log_formatter = twisted.logger.formatEventAsClassicLogText
699 stdout_obs = twisted.logger.FileLogObserver(sys.stdout, log_formatter)
700 stderr_obs = twisted.logger.FileLogObserver(sys.stderr, log_formatter)
701 pred = twisted.logger.LogLevelFilterPredicate(LogLevel.error)
702 stdsomething_obs = twisted.logger.FilteringLogObserver(
703 stderr_obs, [pred], stdout_obs
705 global file_log_observer
706 file_log_observer = twisted.logger.FilteringLogObserver(
707 stdsomething_obs, [LogNotBoringTwisted()]
709 #log_observer = stdsomething_obs
710 twisted.logger.globalLogBeginner.beginLoggingTo(
711 [ file_log_observer, crash_on_critical ]
715 log_debug(DBG.INIT, 'entering reactor')
716 if not _crashing: reactor.run()
717 print('ENDED', file=sys.stderr)