mdw@git.distorted.org.uk Git - hippotat/blob - hippotatd

   1 #!/usr/bin/python3
   2 #
   3 # Hippotat - Asinine IP Over HTTP program
   4 # ./hippotatd - server main program
   5 #
   6 # Copyright 2017 Ian Jackson
   7 #
   8 # AGPLv3+ + CAFv2+
   9 #
  10 #    This program is free software: you can redistribute it and/or
  11 #    modify it under the terms of the GNU Affero General Public
  12 #    License as published by the Free Software Foundation, either
  13 #    version 3 of the License, or (at your option) any later version,
  14 #    with the "CAF Login Exception" as published by Ian Jackson
  15 #    (version 2, or at your option any later version) as an Additional
  16 #    Permission.
  17 #
  18 #    This program is distributed in the hope that it will be useful,
  19 #    but WITHOUT ANY WARRANTY; without even the implied warranty of
  20 #    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  21 #    Affero General Public License for more details.
  22 #
  23 #    You should have received a copy of the GNU Affero General Public
  24 #    License and the CAF Login Exception along with this program, in
  25 #    the file AGPLv3+CAFv2.  If not, email Ian Jackson
  26 #    <ijackson@chiark.greenend.org.uk>.
  27
  28
  29 from hippotatlib import *
  30
  31 import os
  32 import tempfile
  33 import atexit
  34 import shutil
  35 import subprocess
  36
  37 import twisted.internet
  38 from twisted.web.server import NOT_DONE_YET
  39
  40 import twisted.web.static
  41 import twisted.python.syslog
  42
  43 import hippotatlib.ownsource
  44 from hippotatlib.ownsource import SourceShipmentPreparer
  45
  46 #import twisted.web.server import Site
  47 #from twisted.web.resource import Resource
  48
  49 import syslog
  50
  51 cleanups = [ ]
  52
  53 clients = { }
  54
  55 #---------- "router" ----------
  56
  57 def route(packet, iface, saddr, daddr):
  58   def lt(dest):
  59     log_debug(DBG.ROUTE, 'route: %s -> %s: %s' % (saddr,daddr,dest), d=packet)
  60   try: dclient = clients[daddr]
  61   except KeyError: dclient = None
  62   if dclient is not None:
  63     lt('client')
  64     dclient.queue_outbound(packet)
  65   elif daddr == c.vaddr or daddr not in c.vnetwork:
  66     lt('inbound')
  67     queue_inbound(ipif, packet)
  68   elif daddr == c.relay:
  69     lt('discard relay')
  70     log_discard(packet, iface, saddr, daddr, 'relay')
  71   else:
  72     lt('discard no-client')
  73     log_discard(packet, iface, saddr, daddr, 'no-client')
  74
  75 #---------- client ----------
  76
  77 class Client():
  78   def __init__(self, ip, cc):
  79     # instance data members
  80     self._ip = ip
  81     self.cc = cc
  82     self._rq = collections.deque() # requests
  83     self._pq = PacketQueue(str(ip), self.cc.max_queue_time)
  84
  85     if ip not in c.vnetwork:
  86       raise ValueError('client %s not in vnetwork' % ip)
  87
  88     if ip in clients:
  89       raise ValueError('multiple client cfg sections for %s' % ip)
  90     clients[ip] = self
  91
  92     self._log(DBG.INIT, 'new')
  93
  94   def _log(self, dflag, msg, **kwargs):
  95     log_debug(dflag, ('client %s: ' % self._ip)+msg, **kwargs)
  96
  97   def process_arriving_data(self, d):
  98     self._log(DBG.FLOW, "req data (enc'd)", d=d)
  99     if not len(d): return
 100     for packet in slip.decode(d):
 101       (saddr, daddr) = packet_addrs(packet)
 102       if saddr != self._ip:
 103         raise ValueError('wrong source address %s' % saddr)
 104       route(packet, self._ip, saddr, daddr)
 105
 106   def _req_cancel(self, request):
 107     self._log(DBG.HTTP_CTRL, 'cancel', idof=request)
 108     request.finish()
 109
 110   def _req_error(self, err, request):
 111     self._log(DBG.HTTP_CTRL, 'error %s' % err, idof=request)
 112     self._req_cancel(request)
 113
 114   def queue_outbound(self, packet):
 115     self._pq.append(packet)
 116     self._check_outbound()
 117
 118   def _req_fin(self, dummy, request, cl):
 119     self._log(DBG.HTTP_CTRL, '_req_fin ' + repr(dummy), idof=request)
 120     try: cl.cancel()
 121     except twisted.internet.error.AlreadyCalled: pass
 122
 123   def new_request(self, request):
 124     request.setHeader('Content-Type','application/octet-stream')
 125     cl = reactor.callLater(self.cc.http_timeout, self._req_cancel, request)
 126     nf = request.notifyFinish()
 127     nf.addErrback(self._req_error, request)
 128     nf.addCallback(self._req_fin, request, cl)
 129     self._rq.append(request)
 130     self._check_outbound()
 131
 132   def _req_write(self, req, d):
 133     self._log(DBG.HTTP, 'req_write ', idof=req, d=d)
 134     req.write(d)
 135
 136   def _check_outbound(self):
 137     log_debug(DBG.HTTP_CTRL, 'CHKO')
 138     while True:
 139       try: request = self._rq[0]
 140       except IndexError: request = None
 141       if request and request.finished:
 142         self._log(DBG.HTTP_CTRL, 'CHKO req finished, discard', idof=request)
 143         self._rq.popleft()
 144         continue
 145
 146       if not self._pq.nonempty():
 147         # no packets, oh well
 148         self._log(DBG.HTTP_CTRL, 'CHKO no packets, OUT-DONE', idof=request)
 149         break
 150
 151       if request is None:
 152         # no request
 153         self._log(DBG.HTTP_CTRL, 'CHKO no request, OUT-DONE', idof=request)
 154         break
 155
 156       self._log(DBG.HTTP_CTRL, 'CHKO processing', idof=request)
 157       # request, and also some non-expired packets
 158       self._pq.process((lambda: request.sentLength),
 159                        (lambda d: self._req_write(request, d)),
 160                        self.cc.max_batch_down)
 161
 162       assert(request.sentLength)
 163       self._rq.popleft()
 164       request.finish()
 165       self._log(DBG.HTTP, 'complete', idof=request)
 166       # round again, looking for more to do
 167
 168     while len(self._rq) > self.cc.target_requests_outstanding:
 169       request = self._rq.popleft()
 170       self._log(DBG.HTTP, 'CHKO above target, returning empty', idof=request)
 171       request.finish()
 172
 173 def process_request(request, desca):
 174   # find client, update config, etc.
 175   metadata = request.args[b'm'][0]
 176   metadata = metadata.split(b'\r\n')
 177   (ci_s, pw, tro, cto) = metadata[0:4]
 178   desca['m[0,2:3]'] = [ci_s, tro, cto]
 179   ci_s = ci_s.decode('utf-8')
 180   tro = int(tro); desca['tro']= tro
 181   cto = int(cto); desca['cto']= cto
 182   ci = ipaddr(ci_s)
 183   desca['ci'] = ci
 184   cl = clients[ci]
 185   if pw != cl.cc.password: raise ValueError('bad password')
 186   desca['pwok']=True
 187
 188   if tro != cl.cc.target_requests_outstanding:
 189     raise ValueError('tro must be %d' % cl.cc.target_requests_outstanding)
 190
 191   if cto < cl.cc.http_timeout:
 192     raise ValueError('cto must be >= %d' % cl.cc.http_timeout)
 193
 194   try:
 195     d = request.args[b'd'][0]
 196     desca['d'] = d
 197     desca['dlen'] = len(d)
 198   except KeyError:
 199     d = b''
 200     desca['dlen'] = None
 201
 202   log_http(desca, 'processing', idof=id(request), d=d)
 203
 204   d = mime_translate(d)
 205
 206   cl.process_arriving_data(d)
 207   cl.new_request(request)
 208
 209 def log_http(desca, msg, **kwargs):
 210   try:
 211     kwargs['d'] = desca['d']
 212     del desca['d']
 213   except KeyError:
 214     pass
 215   log_debug(DBG.HTTP, msg + repr(desca), **kwargs)
 216
 217 class NotStupidResource(twisted.web.resource.Resource):
 218   # why this is not the default is a mystery!
 219   def getChild(self, name, request):
 220     if name == b'': return self
 221     else: return twisted.web.resource.Resource.getChild(name, request)
 222
 223 class IphttpResource(NotStupidResource):
 224   def render_POST(self, request):
 225     log_debug(DBG.HTTP_FULL,
 226               'req recv: ' + repr(request) + ' ' + repr(request.args),
 227               idof=id(request))
 228     desca = {'d': None}
 229     try: process_request(request, desca)
 230     except Exception as e:
 231       emsg = traceback.format_exc()
 232       log_http(desca, 'RETURNING EXCEPTION ' + emsg)
 233       request.setHeader('Content-Type','text/plain; charset="utf-8"')
 234       request.setResponseCode(400)
 235       return (emsg + ' # ' + repr(desca) + '\r\n').encode('utf-8')
 236     log_debug(DBG.HTTP_CTRL, '...', idof=id(request))
 237     return NOT_DONE_YET
 238
 239   # instantiator should set
 240   # self.hippotat_sources = (source_names[0], source_names[1])
 241   def __init__(self):
 242     self.hippotat_sources = [None, None]
 243     super().__init__()
 244
 245   def render_GET(self, request):
 246     log_debug(DBG.HTTP, 'GET request')
 247     s = '<html><body>hippotat\n'
 248     (s0,s1) = self.hippotat_sources
 249     if s0:
 250       s += '<p><a href="%s">source</a>\n' % s0
 251       if self.hippotat_sources[1]:
 252         s += ('(and that of dependency <a href="%s">packages</a>)\n' % s1)
 253       s += 'available'
 254     else:
 255       s += 'TESTING'
 256     s += '</body></html>'
 257     return s.encode('utf-8')
 258
 259 def start_http():
 260   resource = IphttpResource()
 261   site = twisted.web.server.Site(resource)
 262
 263   for sa in c.saddrs:
 264     ep = sa.make_endpoint()
 265     crash_on_defer(ep.listen(site))
 266     log_debug(DBG.INIT, 'listening on %s' % sa)
 267
 268   td = tempfile.mkdtemp()
 269
 270   def cleanup():
 271     try: shutil.rmtree(td)
 272     except FileNotFoundError: pass
 273
 274   cleanups.append(cleanup)
 275
 276   ssp = SourceShipmentPreparer(td)
 277   ssp.logger = partial(log_debug, DBG.OWNSOURCE)
 278   if DBG.OWNSOURCE in debug_set: ssp.stream_debug = sys.stdout
 279   ssp.download_packages = opts.ownsource >= 2
 280   if opts.ownsource >= 1: ssp.generate()
 281
 282   for ix in (0,1):
 283     bn = ssp.output_names[ix]
 284     op = ssp.output_paths[ix]
 285     if op is None: continue
 286     resource.hippotat_sources[ix] = bn
 287     subresource =twisted.web.static.File(op)
 288     resource.putChild(bn.encode('utf-8'), subresource)
 289
 290   reactor.callLater(0.1, (lambda: log.info('hippotatd started', dflag=False)))
 291
 292 #---------- config and setup ----------
 293
 294 def process_cfg(_opts, putative_servers, putative_clients):
 295   global opts
 296   opts = _opts
 297
 298   global c
 299   c = ConfigResults()
 300   c.server = cfg.get('SERVER','server')
 301
 302   cfg_process_common(c, c.server)
 303   cfg_process_saddrs(c, c.server)
 304   cfg_process_vnetwork(c, c.server)
 305   cfg_process_vaddr(c, c.server)
 306
 307   for (ci,cs) in putative_clients.items():
 308     cc = ConfigResults()
 309     sections = cfg_process_client_common(cc,c.server,cs,ci)
 310     if not sections: continue
 311     cfg_process_client_limited(cc,c.server,sections, 'max_batch_down')
 312     cfg_process_client_limited(cc,c.server,sections, 'max_queue_time')
 313     Client(ci, cc)
 314
 315   try:
 316     c.vrelay = cfg.get(c.server, 'vrelay')
 317   except NoOptionError:
 318     for search in c.vnetwork.hosts():
 319       if search == c.vaddr: continue
 320       c.vrelay = search
 321       break
 322
 323   cfg_process_ipif(c,
 324                    [c.server, 'DEFAULT'],
 325                    (('local','vaddr'),
 326                     ('peer', 'vrelay'),
 327                     ('rnets','vnetwork')))
 328
 329 def catch_termination():
 330   def run_cleanups():
 331     for cleanup in cleanups:
 332       cleanup()
 333
 334   atexit.register(run_cleanups)
 335
 336   def signal_handler(name, sig, *args):
 337     signal.signal(sig, signal.SIG_DFL)
 338     print('exiting due to %s' % name, file=sys.stderr)
 339     run_cleanups()
 340     os.kill(os.getpid(), sig)
 341     raise RuntimeError('did not die due to signal %s !' % name)
 342
 343   for sig in (signal.SIGINT, signal.SIGTERM):
 344     signal.signal(sig, partial(signal_handler, sig.name))
 345
 346 def daemonise():
 347   global syslogfacility
 348   if opts.daemon and opts.syslogfacility is None:
 349     opts.syslogfacility = 'daemon'
 350
 351   if opts.syslogfacility is not None:
 352     facilnum = syslog.__dict__['LOG_' + opts.syslogfacility.upper()]
 353     syslog.openlog('hippotatd',
 354                    facility=facilnum,
 355                    logoption=syslog.LOG_PID)
 356     def emit(event):
 357       m = twisted.logger.formatEvent(event)
 358       #print(repr(event), m, file=org_stderr)
 359       level = event.get('log_level')
 360       if   event.get('dflag',None) is not None: sl = syslog.LOG_DEBUG
 361       elif level == LogLevel.critical         : sl = syslog.LOG_CRIT
 362       elif level == LogLevel.error            : sl = syslog.LOG_ERR
 363       elif level == LogLevel.warn             : sl = syslog.LOG_WARNING
 364       else                                    : sl = syslog.LOG_INFO
 365       syslog.syslog(sl,m)
 366     glp = twisted.logger.globalLogPublisher
 367     glp.addObserver(emit)
 368     log_debug(DBG.INIT, 'starting to log to syslog')
 369
 370   #log.crit('daemonic hippotatd crashed', dflag=False)
 371   if opts.daemon:
 372     daemonic_reactor = (twisted.internet.interfaces.IReactorDaemonize
 373                         .providedBy(reactor))
 374     if daemonic_reactor: reactor.beforeDaemonize()
 375     rfd, wfd = os.pipe()
 376     childpid = os.fork()
 377     if childpid:
 378       # we are the parent
 379       os.close(wfd)
 380       st = os.read(rfd, 1)
 381       try:
 382         st = st[0]
 383       except IndexError:
 384         st = 127
 385         log.critical('daemonic hippotatd crashed', dflag=False)
 386       os._exit(st)
 387     os.close(rfd)
 388     os.setsid()
 389     grandchildpid = os.fork()
 390     if grandchildpid:
 391       # we are the intermediate child
 392       os._exit(0)
 393
 394     logger = subprocess.Popen(['logger','-d',
 395                                '-t','hippotat(stderr)',
 396                                '--id=%d' % os.getpid(),
 397                                '-p',opts.syslogfacility + '.err'],
 398                               stdin=subprocess.PIPE,
 399                               stdout=subprocess.DEVNULL,
 400                               stderr=subprocess.DEVNULL,
 401                               restore_signals=True)
 402
 403     nullfd = os.open('/dev/null', os.O_RDWR)
 404     os.dup2(nullfd, 0)
 405     os.dup2(nullfd, 1)
 406     os.dup2(logger.stdin.fileno(), 2)
 407     os.close(nullfd)
 408     if daemonic_reactor: reactor.afterDaemonize()
 409     log_debug(DBG.INIT, 'daemonised')
 410     os.write(wfd, b'\0')
 411     os.close(wfd)
 412
 413   if opts.syslogfacility is not None:
 414     glp.removeObserver(hippotatlib.file_log_observer)
 415
 416 optparser.add_option('--ownsource', default=2,
 417                      action='store_const', dest='ownsource', const=2,
 418                      help='source download fully enabled (default)')
 419
 420 optparser.add_option('--ownsource-local',
 421                      action='store_const', dest='ownsource', const=1,
 422                      help='source download is local source code only')
 423
 424 optparser.add_option('--no-ownsource',
 425                      action='store_const', dest='ownsource', const=0,
 426                      help='source download disabled (for testing only)')
 427
 428 optparser.add_option('--daemon',
 429                      action='store_true', dest='daemon', default=False,
 430                      help='daemonize (and log to syslog)')
 431
 432 optparser.add_option('--syslog-facility',
 433                      nargs=1, type='string',action='store',
 434                      metavar='FACILITY', dest='syslogfacility',
 435                      default=None,
 436                      help='log to syslog, with specified facility')
 437
 438 common_startup(process_cfg)
 439 catch_termination()
 440 start_http()
 441 daemonise()
 442 ipif = start_ipif(c.ipif_command, (lambda p,s,d: route(p,"[ipif]",s,d)))
 443 common_run()