server

   1 #!/usr/bin/python3
   2
   3 from hippotat import *
   4
   5 import os
   6
   7 import twisted.internet
   8 from twisted.web.server import NOT_DONE_YET
   9
  10 #import twisted.web.server import Site
  11 #from twisted.web.resource import Resource
  12
  13 import syslog
  14
  15 clients = { }
  16
  17 #---------- "router" ----------
  18
  19 def route(packet, saddr, daddr):
  20   print('TRACE ', saddr, daddr, packet)
  21   try: dclient = clients[daddr]
  22   except KeyError: dclient = None
  23   if dclient is not None:
  24     dclient.queue_outbound(packet)
  25   elif daddr == c.server or daddr not in c.network:
  26     print('TRACE INBOUND ', saddr, daddr, packet)
  27     queue_inbound(packet)
  28   elif daddr == relay:
  29     log_discard(packet, saddr, daddr, 'relay')
  30   else:
  31     log_discard(packet, saddr, daddr, 'no client')
  32
  33 #---------- client ----------
  34
  35 class Client():
  36   def __init__(self, ip, cs, pw):
  37     # instance data members
  38     self._ip = ip
  39     self._cs = cs
  40     self.pw = pw
  41     self._rq = collections.deque() # requests
  42     # self._pq = PacketQueue(...)
  43     # plus from config:
  44     #  .max_batch_down
  45     #  .max_queue_time
  46     #  .max_request_time
  47     #  .target_requests_outstanding
  48
  49     if ip not in c.network:
  50       raise ValueError('client %s not in network' % ip)
  51
  52     for k in ('max_batch_down','max_queue_time','max_request_time',
  53               'target_requests_outstanding'):
  54       req = cfg.getint(cs, k)
  55       limit = cfg.getint('limits',k)
  56       self.__dict__[k] = min(req, limit)
  57
  58     self._pq = PacketQueue(self.max_queue_time)
  59
  60     if ip in clients:
  61       raise ValueError('multiple client cfg sections for %s' % ip)
  62     clients[ip] = self
  63
  64   def process_arriving_data(self, d):
  65     for packet in slip.decode(d):
  66       (saddr, daddr) = packet_addrs(packet)
  67       if saddr != self._ip:
  68         raise ValueError('wrong source address %s' % saddr)
  69       route(packet, saddr, daddr)
  70
  71   def _req_cancel(self, request):
  72     request.finish()
  73
  74   def _req_error(self, err, request):
  75     self._req_cancel(request)
  76
  77   def queue_outbound(self, packet):
  78     self._pq.append(packet)
  79     self._check_outbound()
  80
  81   def http_request(self, request):
  82     request.setHeader('Content-Type','application/octet-stream')
  83     reactor.callLater(self.max_request_time, self._req_cancel, request)
  84     request.notifyFinish().addErrback(self._req_error, request)
  85     self._rq.append(request)
  86     self._check_outbound()
  87
  88   def _check_outbound(self):
  89     while True:
  90       try: request = self._rq[0]
  91       except IndexError: request = None
  92       if request and request.finished:
  93         self._rq.popleft()
  94         continue
  95
  96       if not self._pq.nonempty():
  97         # no packets, oh well
  98         continue
  99
 100       if request is None:
 101         # no request
 102         break
 103
 104       # request, and also some non-expired packets
 105       self._pq.process((lambda: request.sentLength),
 106                        request.write,
 107                        self.max_batch_down)
 108
 109       assert(request.sentLength)
 110       self._rq.popleft()
 111       request.finish()
 112       # round again, looking for more to do
 113
 114     while len(self._rq) > self.target_requests_outstanding:
 115       request = self._rq.popleft()
 116       request.finish()
 117
 118 def process_request(request):
 119   # find client, update config, etc.
 120   metadata = request.args['m']
 121   (ci_s, pw, tro) = metadata.split(b'\n')[0:3]
 122   ci = ipaddr(ci_s)
 123   cl = clients[ci]
 124   if pw != cl.pw: raise ValueError('bad password')
 125
 126   if pw != cl.target_requests_outstanding:
 127     raise ...
 128
 129   try: d = request.args['d']
 130   except KeyError: d = ''
 131
 132   cl.process_arriving_data(d)
 133   cl.new_request(request)
 134
 135 class IphttpResource(twisted.web.resource.Resource):
 136   isLeaf = True
 137   def render_POST(self, request):
 138     try: process_request(request)
 139     except Exception as e:
 140       request.setHeader('Content-Type','text/plain; charset="utf-8"')
 141       request.setResponseCode(400)
 142       return str(e).encode('utf-8')
 143
 144   def render_GET(self, request):
 145     return b'<html><body>hippotat</body></html>'
 146
 147 def start_http():
 148   resource = IphttpResource()
 149   site = twisted.web.server.Site(resource)
 150   for sa in c.saddrs:
 151     ep = sa.make_endpoint()
 152     crash_on_defer(ep.listen(site))
 153
 154 #---------- config and setup ----------
 155
 156 def process_cfg():
 157   process_cfg_common_always()
 158   process_cfg_server()
 159   process_cfg_network()
 160
 161   try:
 162     c.relay = cfg.get('virtual','relay')
 163   except NoOptionError:
 164     for search in c.network.hosts():
 165       if search == c.server: continue
 166       c.relay = search
 167       break
 168
 169   process_cfg_saddrs()
 170   process_cfg_clients(Client)
 171
 172   process_cfg_ipif('server',
 173                    (('local','server'),
 174                     ('peer', 'relay'),
 175                     ('rnets','network')))
 176
 177 common_startup()
 178 process_cfg()
 179 start_ipif(c.ipif_command, route)
 180 start_http()
 181 common_run()