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
  36 import twisted.internet
  37 from twisted.web.server import NOT_DONE_YET
  38
  39 import twisted.web.static
  40
  41 import hippotatlib.ownsource
  42 from hippotatlib.ownsource import SourceShipmentPreparer
  43
  44 #import twisted.web.server import Site
  45 #from twisted.web.resource import Resource
  46
  47 import syslog
  48
  49 cleanups = [ ]
  50
  51 clients = { }
  52
  53 #---------- "router" ----------
  54
  55 def route(packet, iface, saddr, daddr):
  56   def lt(dest):
  57     log_debug(DBG.ROUTE, 'route: %s -> %s: %s' % (saddr,daddr,dest), d=packet)
  58   try: dclient = clients[daddr]
  59   except KeyError: dclient = None
  60   if dclient is not None:
  61     lt('client')
  62     dclient.queue_outbound(packet)
  63   elif daddr == c.vaddr or daddr not in c.vnetwork:
  64     lt('inbound')
  65     queue_inbound(ipif, packet)
  66   elif daddr == c.relay:
  67     lt('discard relay')
  68     log_discard(packet, iface, saddr, daddr, 'relay')
  69   else:
  70     lt('discard no-client')
  71     log_discard(packet, iface, saddr, daddr, 'no-client')
  72
  73 #---------- client ----------
  74
  75 class Client():
  76   def __init__(self, ip, cc):
  77     # instance data members
  78     self._ip = ip
  79     self.cc = cc
  80     self._rq = collections.deque() # requests
  81     self._pq = PacketQueue(str(ip), self.cc.max_queue_time)
  82
  83     if ip not in c.vnetwork:
  84       raise ValueError('client %s not in vnetwork' % ip)
  85
  86     if ip in clients:
  87       raise ValueError('multiple client cfg sections for %s' % ip)
  88     clients[ip] = self
  89
  90     self._log(DBG.INIT, 'new')
  91
  92   def _log(self, dflag, msg, **kwargs):
  93     log_debug(dflag, ('client %s: ' % self._ip)+msg, **kwargs)
  94
  95   def process_arriving_data(self, d):
  96     self._log(DBG.FLOW, "req data (enc'd)", d=d)
  97     if not len(d): return
  98     for packet in slip.decode(d):
  99       (saddr, daddr) = packet_addrs(packet)
 100       if saddr != self._ip:
 101         raise ValueError('wrong source address %s' % saddr)
 102       route(packet, self._ip, saddr, daddr)
 103
 104   def _req_cancel(self, request):
 105     self._log(DBG.HTTP_CTRL, 'cancel', idof=request)
 106     request.finish()
 107
 108   def _req_error(self, err, request):
 109     self._log(DBG.HTTP_CTRL, 'error %s' % err, idof=request)
 110     self._req_cancel(request)
 111
 112   def queue_outbound(self, packet):
 113     self._pq.append(packet)
 114     self._check_outbound()
 115
 116   def _req_fin(self, dummy, request, cl):
 117     self._log(DBG.HTTP_CTRL, '_req_fin ' + repr(dummy), idof=request)
 118     try: cl.cancel()
 119     except twisted.internet.error.AlreadyCalled: pass
 120
 121   def new_request(self, request):
 122     request.setHeader('Content-Type','application/octet-stream')
 123     cl = reactor.callLater(self.cc.http_timeout, self._req_cancel, request)
 124     nf = request.notifyFinish()
 125     nf.addErrback(self._req_error, request)
 126     nf.addCallback(self._req_fin, request, cl)
 127     self._rq.append(request)
 128     self._check_outbound()
 129
 130   def _req_write(self, req, d):
 131     self._log(DBG.HTTP, 'req_write ', idof=req, d=d)
 132     req.write(d)
 133
 134   def _check_outbound(self):
 135     log_debug(DBG.HTTP_CTRL, 'CHKO')
 136     while True:
 137       try: request = self._rq[0]
 138       except IndexError: request = None
 139       if request and request.finished:
 140         self._log(DBG.HTTP_CTRL, 'CHKO req finished, discard', idof=request)
 141         self._rq.popleft()
 142         continue
 143
 144       if not self._pq.nonempty():
 145         # no packets, oh well
 146         self._log(DBG.HTTP_CTRL, 'CHKO no packets, OUT-DONE', idof=request)
 147         break
 148
 149       if request is None:
 150         # no request
 151         self._log(DBG.HTTP_CTRL, 'CHKO no request, OUT-DONE', idof=request)
 152         break
 153
 154       self._log(DBG.HTTP_CTRL, 'CHKO processing', idof=request)
 155       # request, and also some non-expired packets
 156       self._pq.process((lambda: request.sentLength),
 157                        (lambda d: self._req_write(request, d)),
 158                        self.cc.max_batch_down)
 159
 160       assert(request.sentLength)
 161       self._rq.popleft()
 162       request.finish()
 163       self._log(DBG.HTTP, 'complete', idof=request)
 164       # round again, looking for more to do
 165
 166     while len(self._rq) > self.cc.target_requests_outstanding:
 167       request = self._rq.popleft()
 168       self._log(DBG.HTTP, 'CHKO above target, returning empty', idof=request)
 169       request.finish()
 170
 171 def process_request(request, desca):
 172   # find client, update config, etc.
 173   metadata = request.args[b'm'][0]
 174   metadata = metadata.split(b'\r\n')
 175   (ci_s, pw, tro, cto) = metadata[0:4]
 176   desca['m[0,2:3]'] = [ci_s, tro, cto]
 177   ci_s = ci_s.decode('utf-8')
 178   tro = int(tro); desca['tro']= tro
 179   cto = int(cto); desca['cto']= cto
 180   ci = ipaddr(ci_s)
 181   desca['ci'] = ci
 182   cl = clients[ci]
 183   if pw != cl.cc.password: raise ValueError('bad password')
 184   desca['pwok']=True
 185
 186   if tro != cl.cc.target_requests_outstanding:
 187     raise ValueError('tro must be %d' % cl.cc.target_requests_outstanding)
 188
 189   if cto < cl.cc.http_timeout:
 190     raise ValueError('cto must be >= %d' % cl.cc.http_timeout)
 191
 192   try:
 193     d = request.args[b'd'][0]
 194     desca['d'] = d
 195     desca['dlen'] = len(d)
 196   except KeyError:
 197     d = b''
 198     desca['dlen'] = None
 199
 200   log_http(desca, 'processing', idof=id(request), d=d)
 201
 202   d = mime_translate(d)
 203
 204   cl.process_arriving_data(d)
 205   cl.new_request(request)
 206
 207 def log_http(desca, msg, **kwargs):
 208   try:
 209     kwargs['d'] = desca['d']
 210     del desca['d']
 211   except KeyError:
 212     pass
 213   log_debug(DBG.HTTP, msg + repr(desca), **kwargs)
 214
 215 class NotStupidResource(twisted.web.resource.Resource):
 216   # why this is not the default is a mystery!
 217   def getChild(self, name, request):
 218     if name == b'': return self
 219     else: return twisted.web.resource.Resource.getChild(name, request)
 220
 221 class IphttpResource(NotStupidResource):
 222   def render_POST(self, request):
 223     log_debug(DBG.HTTP_FULL,
 224               'req recv: ' + repr(request) + ' ' + repr(request.args),
 225               idof=id(request))
 226     desca = {'d': None}
 227     try: process_request(request, desca)
 228     except Exception as e:
 229       emsg = traceback.format_exc()
 230       log_http(desca, 'RETURNING EXCEPTION ' + emsg)
 231       request.setHeader('Content-Type','text/plain; charset="utf-8"')
 232       request.setResponseCode(400)
 233       return (emsg + ' # ' + repr(desca) + '\r\n').encode('utf-8')
 234     log_debug(DBG.HTTP_CTRL, '...', idof=id(request))
 235     return NOT_DONE_YET
 236
 237   # instantiator should set
 238   # self.hippotat_sources = (source_names[0], source_names[1])
 239   def __init__(self):
 240     self.hippotat_sources = [None, None]
 241     super().__init__()
 242
 243   def render_GET(self, request):
 244     log_debug(DBG.HTTP, 'GET request')
 245     return ('''
 246 <html><body>
 247 hippotat
 248 <p>
 249 <a href="%s">source</a>
 250 (and that of dependency <a href="%s">packages</a>)
 251 available
 252 </body></html>
 253 '''
 254             % tuple(self.hippotat_sources)).encode('utf-8')
 255
 256 def start_http():
 257   resource = IphttpResource()
 258   site = twisted.web.server.Site(resource)
 259
 260   for sa in c.saddrs:
 261     ep = sa.make_endpoint()
 262     crash_on_defer(ep.listen(site))
 263     log_debug(DBG.INIT, 'listening on %s' % sa)
 264
 265   td = tempfile.mkdtemp()
 266
 267   def cleanup():
 268     try: shutil.rmtree(td)
 269     except FileNotFoundError: pass
 270
 271   cleanups.append(cleanup)
 272
 273   ssp = SourceShipmentPreparer(td)
 274   ssp.logger = partial(log_debug, DBG.OWNSOURCE)
 275   if DBG.OWNSOURCE in debug_set: ssp.stream_debug = sys.stdout
 276   ssp.generate()
 277
 278   for ix in (0,1):
 279     bn = ssp.output_names[ix]
 280     op = ssp.output_paths[ix]
 281     resource.hippotat_sources[ix] = bn
 282     subresource =twisted.web.static.File(op)
 283     resource.putChild(bn.encode('utf-8'), subresource)
 284
 285   reactor.callLater(0.1, (lambda: log.info('hippotatd started', dflag=False)))
 286
 287 #---------- config and setup ----------
 288
 289 def process_cfg(_opts, putative_servers, putative_clients):
 290   global opts
 291   opts = _opts
 292
 293   global c
 294   c = ConfigResults()
 295   c.server = cfg.get('SERVER','server')
 296
 297   cfg_process_common(c, c.server)
 298   cfg_process_saddrs(c, c.server)
 299   cfg_process_vnetwork(c, c.server)
 300   cfg_process_vaddr(c, c.server)
 301
 302   for (ci,cs) in putative_clients.items():
 303     cc = ConfigResults()
 304     sections = cfg_process_client_common(cc,c.server,cs,ci)
 305     if not sections: continue
 306     cfg_process_client_limited(cc,c.server,sections, 'max_batch_down')
 307     cfg_process_client_limited(cc,c.server,sections, 'max_queue_time')
 308     Client(ci, cc)
 309
 310   try:
 311     c.vrelay = cfg.get(c.server, 'vrelay')
 312   except NoOptionError:
 313     for search in c.vnetwork.hosts():
 314       if search == c.vaddr: continue
 315       c.vrelay = search
 316       break
 317
 318   cfg_process_ipif(c,
 319                    [c.server, 'DEFAULT'],
 320                    (('local','vaddr'),
 321                     ('peer', 'vrelay'),
 322                     ('rnets','vnetwork')))
 323
 324 def catch_termination():
 325   def run_cleanups():
 326     for cleanup in cleanups:
 327       cleanup()
 328
 329   atexit.register(run_cleanups)
 330
 331   def signal_handler(name, sig, *args):
 332     signal.signal(sig, signal.SIG_DFL)
 333     print('exiting due to %s' % name, file=sys.stderr)
 334     run_cleanups()
 335     os.kill(os.getpid(), sig)
 336     raise RuntimeError('did not die due to signal %s !' % name)
 337
 338   for sig in (signal.SIGINT, signal.SIGTERM):
 339     signal.signal(sig, partial(signal_handler, sig.name))
 340
 341 common_startup(process_cfg)
 342 catch_termination()
 343 ipif = start_ipif(c.ipif_command, (lambda p,s,d: route(p,"[ipif]",s,d)))
 344 start_http()
 345 common_run()