chiark / gitweb /
e5aa67b588878fca227564a896f808e2fd5382f6
[hippotat.git] / 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 import traceback
16
17 clients = { }
18
19 #---------- "router" ----------
20
21 def route(packet, iface, saddr, daddr):
22   def lt(dest):
23     log_debug(DBG.ROUTE, 'route: %s -> %s: %s' % (saddr,daddr,dest), d=packet)
24   try: dclient = clients[daddr]
25   except KeyError: dclient = None
26   if dclient is not None:
27     lt('client')
28     dclient.queue_outbound(packet)
29   elif daddr == c.server or daddr not in c.network:
30     lt('inbound')
31     queue_inbound(packet)
32   elif daddr == relay:
33     lt('discard relay')
34     log_discard(packet, iface, saddr, daddr, 'relay')
35   else:
36     lt('discard no-client')
37     log_discard(packet, iface, saddr, daddr, 'no-client')
38
39 #---------- client ----------
40
41 class Client():
42   def __init__(self, ip, cs, pw):
43     # instance data members
44     self._ip = ip
45     self._cs = cs
46     self.pw = pw
47     self._rq = collections.deque() # requests
48     # self._pq = PacketQueue(...)
49     # plus from config:
50     #  .max_batch_down
51     #  .max_queue_time
52     #  .max_request_time
53     #  .target_requests_outstanding
54
55     if ip not in c.network:
56       raise ValueError('client %s not in network' % ip)
57
58     for k in ('max_batch_down','max_queue_time','max_request_time',
59               'target_requests_outstanding'):
60       req = cfg.getint(cs, k)
61       limit = cfg.getint('limits',k)
62       self.__dict__[k] = min(req, limit)
63
64     self._pq = PacketQueue(str(ip), self.max_queue_time)
65
66     if ip in clients:
67       raise ValueError('multiple client cfg sections for %s' % ip)
68     clients[ip] = self
69
70     self._log(DBG.INIT, 'new')
71
72   def _log(self, dflag, msg, **kwargs):
73     log_debug(dflag, ('client %s: ' % self._ip)+msg, **kwargs)
74
75   def process_arriving_data(self, d):
76     self._log(DBG.FLOW, "req data (enc'd)", d=d)
77     if not len(d): return
78     for packet in slip.decode(d):
79       (saddr, daddr) = packet_addrs(packet)
80       if saddr != self._ip:
81         raise ValueError('wrong source address %s' % saddr)
82       route(packet, self._ip, saddr, daddr)
83
84   def _req_cancel(self, request):
85     self._log(DBG.HTTP_CTRL, 'cancel', idof=request)
86     request.finish()
87
88   def _req_error(self, err, request):
89     self._log(DBG.HTTP_CTRL, 'error %s' % err, idof=request)
90     self._req_cancel(request)
91
92   def queue_outbound(self, packet):
93     self._pq.append(packet)
94     self._check_outbound()
95
96   def new_request(self, request):
97     request.setHeader('Content-Type','application/octet-stream')
98     reactor.callLater(self.max_request_time, self._req_cancel, request)
99     request.notifyFinish().addErrback(self._req_error, request)
100     self._rq.append(request)
101     self._check_outbound()
102
103   def _check_outbound(self):
104     log_debug(DBG.HTTP_CTRL, 'CHKO')
105     while True:
106       try: request = self._rq[0]
107       except IndexError: request = None
108       if request and request.finished:
109         self._log(DBG.HTTP_CTRL, 'CHKO req finished, discard', idof=request)
110         self._rq.popleft()
111         continue
112
113       if not self._pq.nonempty():
114         # no packets, oh well
115         self._log(DBG.HTTP_CTRL, 'CHKO no packets, OUT-DONE', idof=request)
116         break
117
118       if request is None:
119         # no request
120         self._log(DBG.HTTP_CTRL, 'CHKO no request, OUT-DONE', idof=request)
121         break
122
123       self._log(DBG.HTTP_CTRL, 'CHKO processing', idof=request)
124       # request, and also some non-expired packets
125       self._pq.process((lambda: request.sentLength),
126                        request.write,
127                        self.max_batch_down)
128
129       assert(request.sentLength)
130       self._rq.popleft()
131       request.finish()
132       self._log(DBG.HTTP, 'complete', idof=request)
133       # round again, looking for more to do
134
135     while len(self._rq) > self.target_requests_outstanding:
136       request = self._rq.popleft()
137       self._log(DBG.HTTP, 'CHKO above target, returning empty', idof=request)
138       request.finish()
139
140 def process_request(request, desca):
141   # find client, update config, etc.
142   metadata = request.args[b'm'][0]
143   metadata = metadata.split(b'\r\n')
144   (ci_s, pw, tro) = metadata[0:3]
145   desca['m[0,2]'] = [ci_s, tro]
146   ci_s = ci_s.decode('utf-8')
147   tro = int(tro)
148   desca['tro']= tro
149   ci = ipaddr(ci_s)
150   desca['ci'] = ci
151   cl = clients[ci]
152   if pw != cl.pw: raise ValueError('bad password')
153   desca['pwok']=True
154
155   if tro != cl.target_requests_outstanding:
156     raise ValueError('tro must be %d' % cl.target_requests_outstanding)
157
158   try:
159     d = request.args[b'd'][0]
160     desca['d'] = d
161     desca['dlen'] = len(d)
162   except KeyError:
163     d = b''
164     desca['dlen'] = None
165
166   log_http(desca, 'processing', idof=id(request), d=d)
167
168   d = mime_translate(d)
169
170   cl.process_arriving_data(d)
171   cl.new_request(request)
172
173 def log_http(desca, msg, **kwargs):
174   try:
175     kwargs['d'] = desca['d']
176     del desca['d']
177   except KeyError:
178     pass
179   log_debug(DBG.HTTP, msg + repr(desca), **kwargs)
180
181 class IphttpResource(twisted.web.resource.Resource):
182   isLeaf = True
183   def render_POST(self, request):
184     log_debug(DBG.HTTP_FULL,
185               'req recv: ' + repr(request) + ' ' + repr(request.args),
186               idof=id(request))
187     desca = {'d': None}
188     try: process_request(request, desca)
189     except Exception as e:
190       emsg = traceback.format_exc()
191       log_http(desca, 'RETURNING EXCEPTION ' + emsg)
192       request.setHeader('Content-Type','text/plain; charset="utf-8"')
193       request.setResponseCode(400)
194       return (emsg + ' # ' + repr(desca) + '\r\n').encode('utf-8')
195     log_debug(DBG.HTTP_CTRL, '...', idof=id(request))
196     return NOT_DONE_YET
197
198   def render_GET(self, request):
199     log_debug(DBG.HTTP, 'GET request')
200     return b'<html><body>hippotat</body></html>'
201
202 def start_http():
203   resource = IphttpResource()
204   site = twisted.web.server.Site(resource)
205   for sa in c.saddrs:
206     ep = sa.make_endpoint()
207     crash_on_defer(ep.listen(site))
208     log_debug(DBG.INIT, 'listening on %s' % sa)
209
210 #---------- config and setup ----------
211         
212 def process_cfg():
213   process_cfg_common_always()
214   process_cfg_server()
215   process_cfg_network()
216
217   try:
218     c.relay = cfg.get('virtual','relay')
219   except NoOptionError:
220     for search in c.network.hosts():
221       if search == c.server: continue
222       c.relay = search
223       break
224
225   process_cfg_saddrs()
226   process_cfg_clients(Client)
227
228   process_cfg_ipif('server',
229                    (('local','server'),
230                     ('peer', 'relay'),
231                     ('rnets','network')))
232
233 common_startup()
234 process_cfg()
235 start_ipif(c.ipif_command, (lambda p,s,d: route(p,"[ipif]",s,d)))
236 start_http()
237 common_run()