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(server_pat + r' ' + client_pat)
391 for cs in cfg.sections():
392 if cs == 'LIMIT' or cs == 'COMMON':
393 # plan A "[LIMIT]" or "[COMMON]"
397 # plan B "[<client>]" part 1
399 except AddressValueError:
401 if server_re.fullmatch(cs):
402 # plan C "[<servername>]"
403 putative(servers, cs, cs)
406 if serverclient_re.fullmatch(cs):
407 # plan D "[<servername> <client>]" part 1
408 (pss,pcs) = cs.split(' ')
411 # plan E "[<servername> LIMIT]"
415 # plan D "[<servername> <client>]" part 2
417 except AddressValueError:
418 # plan F "[<some thing we do not understand>]"
419 # well, we ignore this
420 print('warning: ignoring config section %s' % cs, file=sys.stderr)
423 else: # no AddressValueError
424 # plan D "[<servername> <client]" part 3
425 putative(clients, ci, pcs)
426 putative(servers, pss, pss)
429 else: # no AddressValueError
430 # plan B "[<client>" part 2
431 putative(clients, ci, cs)
434 return (servers, clients)
436 def cfg_process_general(c, ss):
437 c.mtu = cfg1getint(ss, 'mtu')
439 def cfg_process_saddrs(c, ss):
441 def __init__(self, port, addrspec):
445 self.addr = ipaddress.IPv4Address(addrspec)
446 self._endpointfactory = twisted.internet.endpoints.TCP4ServerEndpoint
448 except AddressValueError:
449 self.addr = ipaddress.IPv6Address(addrspec)
450 self._endpointfactory = twisted.internet.endpoints.TCP6ServerEndpoint
451 self._inurl = b'[%s]'
452 def make_endpoint(self):
453 return self._endpointfactory(reactor, self.port,
454 interface= '%s' % self.addr)
456 url = b'http://' + (self._inurl % str(self.addr).encode('ascii'))
457 if self.port != 80: url += b':%d' % self.port
461 return 'ServerAddr'+repr((self.port,self.addr))
463 c.port = cfg1getint(ss,'port')
465 for addrspec in cfg1get(ss, 'addrs').split():
466 sa = ServerAddr(c.port, addrspec)
469 def cfg_process_vnetwork(c, ss):
470 c.vnetwork = ipnetwork(cfg1get(ss,'vnetwork'))
471 if c.vnetwork.num_addresses < 3 + 2:
472 raise ValueError('vnetwork needs at least 2^3 addresses')
474 def cfg_process_vaddr(c, ss):
476 c.vaddr = cfg1get(ss,'vaddr')
477 except NoOptionError:
478 cfg_process_vnetwork(c, ss)
479 c.vaddr = next(c.vnetwork.hosts())
481 def cfg_search_section(key,sections):
482 for section in sections:
483 if cfg.has_option(section, key):
485 raise NoOptionError(key, repr(sections))
487 def cfg_get_raw(*args, **kwargs):
488 # for passing to cfg_search
489 return cfg.get(*args, raw=True, **kwargs)
491 def cfg_search(getter,key,sections):
492 section = cfg_search_section(key,sections)
493 return getter(section, key)
495 def cfg1get(section,key, getter=cfg.get,**kwargs):
496 section = cfg_search_section(key,[section,'COMMON'])
497 return getter(section,key,**kwargs)
499 def cfg1getint(section,key, **kwargs):
500 return cfg1get(section,key, getter=cfg.getint,**kwargs);
502 def cfg_process_client_limited(cc,ss,sections,key):
503 val = cfg_search(cfg1getint, key, sections)
504 lim = cfg_search(cfg1getint, key, ['%s LIMIT' % ss, 'LIMIT'])
505 cc.__dict__[key] = min(val,lim)
507 def cfg_process_client_common(cc,ss,cs,ci):
508 # returns sections to search in, iff password is defined, otherwise None
511 sections = ['%s %s' % (ss,cs),
516 try: pwsection = cfg_search_section('password', sections)
517 except NoOptionError: return None
519 pw = cfg1get(pwsection, 'password')
520 cc.password = pw.encode('utf-8')
522 cfg_process_client_limited(cc,ss,sections,'target_requests_outstanding')
523 cfg_process_client_limited(cc,ss,sections,'http_timeout')
527 def cfg_process_ipif(c, sections, varmap):
529 try: v = getattr(c, s)
530 except AttributeError: continue
533 #print('CFGIPIF',repr((varmap, sections, c.__dict__)),file=sys.stderr)
535 section = cfg_search_section('ipif', sections)
536 c.ipif_command = cfg1get(section,'ipif', vars=c.__dict__)
538 #---------- startup ----------
540 def log_debug_config(m):
541 if not DBG.CONFIG in debug_set: return
542 print('DBG.CONFIG:', m)
544 def common_startup(process_cfg):
545 # calls process_cfg(putative_clients, putative_servers)
547 # ConfigParser hates #-comments after values
548 trailingcomments_re = regexp.compile(r'#.*')
549 cfg.read_string(trailingcomments_re.sub('', defcfg))
552 def readconfig(pathname, mandatory=True):
553 def log(m, p=pathname):
554 if not DBG.CONFIG in debug_set: return
555 log_debug_config('%s: %s' % (m, p))
558 files = os.listdir(pathname)
560 except FileNotFoundError:
565 except NotADirectoryError:
572 re = regexp.compile('[^-A-Za-z0-9_]')
573 for f in os.listdir(pathname):
574 if re.search(f): continue
575 subpath = pathname + '/' + f
578 except FileNotFoundError:
579 log('entry skipped', subpath)
582 log('entry read', subpath)
584 def oc_config(od,os, value, op):
589 def oc_extra_config(od,os, value, op):
592 def read_defconfig():
593 readconfig('/etc/hippotat/config.d', False)
594 readconfig('/etc/hippotat/passwords.d', False)
595 readconfig('/etc/hippotat/master.cfg', False)
597 def oc_defconfig(od,os, value, op):
600 read_defconfig(value)
602 def dfs_less_detailed(dl):
603 return [df for df in DBG.iterconstants() if df <= dl]
605 def ds_default(od,os,dl,op):
608 debug_set |= set(dfs_less_detailed(debug_def_detail))
610 def ds_select(od,os, spec, op):
611 for it in spec.split(','):
613 if it.startswith('-'):
614 mutator = debug_set.discard
617 mutator = debug_set.add
620 dfs = DBG.iterconstants()
624 mapper = dfs_less_detailed
627 mapper = lambda x: [x]
630 dfspec = DBG.lookupByName(it)
632 optparser.error('unknown debug flag %s in --debug-select' % it)
639 optparser.add_option('-D', '--debug',
642 help='enable default debug (to stdout)',
643 callback= ds_default)
645 optparser.add_option('--debug-select',
648 metavar='[-]DFLAG[+]|[-]+,...',
650 '''enable (`-': disable) each specified DFLAG;
651 `+': do same for all "more interesting" DFLAGSs;
652 just `+': all DFLAGs.
653 DFLAGS: ''' + ' '.join([df.name for df in DBG.iterconstants()]),
657 optparser.add_option('-c', '--config',
660 metavar='CONFIGFILE',
665 optparser.add_option('--extra-config',
668 metavar='CONFIGFILE',
671 callback= oc_extra_config)
673 optparser.add_option('--default-config',
675 callback= oc_defconfig)
677 (opts, args) = optparser.parse_args()
678 if len(args): optparser.error('no non-option arguments please')
684 (pss, pcs) = _cfg_process_putatives()
685 process_cfg(opts, pss, pcs)
686 except (configparser.Error, ValueError):
687 traceback.print_exc(file=sys.stderr)
688 print('\nInvalid configuration, giving up.', file=sys.stderr)
692 #print('X', debug_set, file=sys.stderr)
694 log_formatter = twisted.logger.formatEventAsClassicLogText
695 stdout_obs = twisted.logger.FileLogObserver(sys.stdout, log_formatter)
696 stderr_obs = twisted.logger.FileLogObserver(sys.stderr, log_formatter)
697 pred = twisted.logger.LogLevelFilterPredicate(LogLevel.error)
698 stdsomething_obs = twisted.logger.FilteringLogObserver(
699 stderr_obs, [pred], stdout_obs
701 global file_log_observer
702 file_log_observer = twisted.logger.FilteringLogObserver(
703 stdsomething_obs, [LogNotBoringTwisted()]
705 #log_observer = stdsomething_obs
706 twisted.logger.globalLogBeginner.beginLoggingTo(
707 [ file_log_observer, crash_on_critical ]
711 log_debug(DBG.INIT, 'entering reactor')
712 if not _crashing: reactor.run()
713 print('ENDED', file=sys.stderr)