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 #@ import sys; sys.path.append('@PYBUILD_INSTALL_DIR@')
  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
  42 import hippotatlib.ownsource
  43 from hippotatlib.ownsource import SourceShipmentPreparer
  44
  45 #import twisted.web.server import Site
  46 #from twisted.web.resource import Resource
  47
  48 import syslog
  49
  50 cleanups = [ ]
  51
  52 clients = { }
  53
  54 #---------- "router" ----------
  55
  56 def route(packet, iface, saddr, daddr):
  57   def lt(dest):
  58     log_debug(DBG.ROUTE, 'route: %s -> %s: %s' % (saddr,daddr,dest), d=packet)
  59   try: dclient = clients[daddr]
  60   except KeyError: dclient = None
  61   if dclient is not None:
  62     lt('client')
  63     dclient.queue_outbound(packet)
  64   elif daddr == c.vaddr or daddr not in c.vnetwork:
  65     lt('inbound')
  66     queue_inbound(ipif, packet)
  67   elif daddr == c.vrelay:
  68     lt('discard relay')
  69     log_discard(packet, iface, saddr, daddr, 'relay')
  70   else:
  71     lt('discard no-client')
  72     log_discard(packet, iface, saddr, daddr, 'no-client')
  73
  74 #---------- client ----------
  75
  76 class Client():
  77   def __init__(self, ip, cc):
  78     # instance data members
  79     self._ip = ip
  80     self.cc = cc
  81     self._rq = collections.deque() # requests
  82     self._pq = PacketQueue(str(ip), self.cc.max_queue_time)
  83
  84     if ip not in c.vnetwork:
  85       raise ValueError('client %s not in vnetwork' % ip)
  86
  87     if ip in clients:
  88       raise ValueError('multiple client cfg sections for %s' % ip)
  89     clients[ip] = self
  90
  91     self._log(DBG.INIT, 'new')
  92
  93   def _log(self, dflag, msg, **kwargs):
  94     log_debug(dflag, ('client %s: ' % self._ip)+msg, **kwargs)
  95
  96   def process_arriving_data(self, d):
  97     self._log(DBG.FLOW, "req data (enc'd)", d=d)
  98     if not len(d): return
  99     for packet in slip.decode(d):
 100       (saddr, daddr) = packet_addrs(packet)
 101       if saddr != self._ip:
 102         raise ValueError('wrong source address %s' % saddr)
 103       route(packet, self._ip, saddr, daddr)
 104
 105   def _req_cancel(self, request):
 106     self._log(DBG.HTTP_CTRL, 'cancel', idof=request)
 107     try: request.finish()
 108     except Exception: pass
 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,nf))
 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,nf) = self._rq[0]
 140       except IndexError: request = None
 141       if request and nf.called:
 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, nf) = 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   try: c.server = cfg1get('SERVER','server')
 301   except NoOptionError: c.server = 'SERVER'
 302
 303   cfg_process_general(c, c.server)
 304   cfg_process_saddrs(c, c.server)
 305   cfg_process_vnetwork(c, c.server)
 306   cfg_process_vaddr(c, c.server)
 307
 308   for (ci,cs) in putative_clients.items():
 309     cc = ConfigResults()
 310     sections = cfg_process_client_common(cc,c.server,cs,ci)
 311     if not sections: continue
 312     cfg_process_client_limited(cc,c.server,sections, 'max_batch_down')
 313     cfg_process_client_limited(cc,c.server,sections, 'max_queue_time')
 314     Client(ci, cc)
 315
 316   try:
 317     c.vrelay = cfg1get(c.server, 'vrelay')
 318   except NoOptionError:
 319     for search in c.vnetwork.hosts():
 320       if search == c.vaddr: continue
 321       c.vrelay = search
 322       break
 323
 324   try: c.ifname = cfg1get(c.server, 'ifname_server', raw=True)
 325   except NoOptionError: pass
 326
 327   cfg_process_ipif(c,
 328                    [c.server, 'COMMON'],
 329                    (('local','vaddr'),
 330                     ('peer', 'vrelay'),
 331                     ('rnets','vnetwork')))
 332
 333   if opts.printconfig is not None:
 334     try: val = cfg1get(c.server, opts.printconfig)
 335     except NoOptionError: pass
 336     else: print(val)
 337     sys.exit(0)
 338
 339 def catch_termination():
 340   def run_cleanups():
 341     for cleanup in cleanups:
 342       cleanup()
 343
 344   atexit.register(run_cleanups)
 345
 346   def signal_handler(name, sig, *args):
 347     signal.signal(sig, signal.SIG_DFL)
 348     print('exiting due to %s' % name, file=sys.stderr)
 349     run_cleanups()
 350     os.kill(os.getpid(), sig)
 351     raise RuntimeError('did not die due to signal %s !' % name)
 352
 353   for sig in (signal.SIGINT, signal.SIGTERM):
 354     try: signame = sig.name
 355     except AttributeError: signame = "signal %d" % sig
 356     signal.signal(sig, partial(signal_handler, signame))
 357
 358 def daemonise():
 359   global syslogfacility
 360   if opts.daemon and opts.syslogfacility is None:
 361     opts.syslogfacility = 'daemon'
 362
 363   if opts.syslogfacility is not None:
 364     facilnum = syslog.__dict__['LOG_' + opts.syslogfacility.upper()]
 365     syslog.openlog('hippotatd',
 366                    facility=facilnum,
 367                    logoption=syslog.LOG_PID)
 368     def emit(event):
 369       if logevent_is_boringtwisted(event): return
 370       m = twisted.logger.formatEvent(event)
 371       #print(repr(event), m, file=org_stderr)
 372       level = event.get('log_level')
 373       if   event.get('dflag',None) is not None: sl = syslog.LOG_DEBUG
 374       elif level == LogLevel.critical         : sl = syslog.LOG_CRIT
 375       elif level == LogLevel.error            : sl = syslog.LOG_ERR
 376       elif level == LogLevel.warn             : sl = syslog.LOG_WARNING
 377       else                                    : sl = syslog.LOG_INFO
 378       syslog.syslog(sl,m)
 379       failure = event.get('log_failure')
 380       if failure is not None:
 381         for l in failure.getTraceback().split('\n'):
 382           syslog.syslog(sl,l)
 383     glp = twisted.logger.globalLogPublisher
 384     glp.addObserver(emit)
 385     log_debug(DBG.INIT, 'starting to log to syslog')
 386
 387   #log.crit('daemonic hippotatd crashed', dflag=False)
 388   if opts.daemon:
 389     daemonic_reactor = (twisted.internet.interfaces.IReactorDaemonize
 390                         .providedBy(reactor))
 391     if daemonic_reactor: reactor.beforeDaemonize()
 392     if opts.pidfile is not None:
 393       pidfile_h = open(opts.pidfile, 'w')
 394     rfd, wfd = os.pipe()
 395     childpid = os.fork()
 396     if childpid:
 397       # we are the parent
 398       os.close(wfd)
 399       st = os.read(rfd, 1)
 400       try:
 401         st = st[0]
 402       except IndexError:
 403         st = 127
 404         log.critical('daemonic hippotatd crashed', dflag=False)
 405       os._exit(st)
 406     os.close(rfd)
 407     os.setsid()
 408     grandchildpid = os.fork()
 409     if grandchildpid:
 410       # we are the intermediate child
 411       if opts.pidfile is not None:
 412         print(grandchildpid, file=pidfile_h)
 413         pidfile_h.close()
 414       os._exit(0)
 415
 416     if opts.pidfile is not None:
 417       pidfile_h.close()
 418
 419     logger = subprocess.Popen(['logger','-d',
 420                                '-t','hippotat[%d](stderr)' % os.getpid(),
 421                                '-p',opts.syslogfacility + '.err'],
 422                               stdin=subprocess.PIPE,
 423                               stdout=subprocess.DEVNULL,
 424                               stderr=subprocess.DEVNULL,
 425                               restore_signals=True)
 426
 427     nullfd = os.open('/dev/null', os.O_RDWR)
 428     os.dup2(nullfd, 0)
 429     os.dup2(nullfd, 1)
 430     os.dup2(logger.stdin.fileno(), 2)
 431     os.close(nullfd)
 432     if daemonic_reactor: reactor.afterDaemonize()
 433     log_debug(DBG.INIT, 'daemonised')
 434     os.write(wfd, b'\0')
 435     os.close(wfd)
 436
 437   if opts.syslogfacility is not None:
 438     glp.removeObserver(hippotatlib.file_log_observer)
 439
 440 optparser.add_option('--ownsource', default=2,
 441                      action='store_const', dest='ownsource', const=2,
 442                      help='source download fully enabled (default)')
 443
 444 optparser.add_option('--ownsource-local',
 445                      action='store_const', dest='ownsource', const=1,
 446                      help='source download is local source code only')
 447
 448 optparser.add_option('--no-ownsource',
 449                      action='store_const', dest='ownsource', const=0,
 450                      help='source download disabled (for testing only)')
 451
 452 optparser.add_option('--daemon',
 453                      action='store_true', dest='daemon', default=False,
 454                      help='daemonize (and log to syslog)')
 455
 456 optparser.add_option('--pidfile',
 457                      nargs=1, type='string',
 458                      action='store', dest='pidfile', default=None,
 459                      help='write pid to this file')
 460
 461 optparser.add_option('--syslog-facility',
 462                      nargs=1, type='string',action='store',
 463                      metavar='FACILITY', dest='syslogfacility',
 464                      default=None,
 465                      help='log to syslog, with specified facility')
 466
 467 optparser.add_option('--print-config',
 468                      nargs=1, type='string',action='store',
 469                      metavar='OPTION', dest='printconfig',
 470                      default=None,
 471                      help='print one config option value and exit')
 472
 473 common_startup(process_cfg)
 474 catch_termination()
 475 start_http()
 476 daemonise()
 477 ipif = start_ipif(c.ipif_command, (lambda p,s,d: route(p,"[ipif]",s,d)))
 478 common_run()