chiark / gitweb /
7c66edd2892fd52ea6825fbb9d4b7b594a0e2fab
[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 clients = { }
16
17 #---------- "router" ----------
18
19 def route(packet, iface, saddr, daddr):
20   def lt(dest):
21     log_debug(DBG.ROUTE, 'route: %s -> %s: %s' % (saddr,daddr,dest), d=packet)
22   try: dclient = clients[daddr]
23   except KeyError: dclient = None
24   if dclient is not None:
25     lt('client')
26     dclient.queue_outbound(packet)
27   elif daddr == c.server or daddr not in c.network:
28     lt('inbound')
29     queue_inbound(packet)
30   elif daddr == relay:
31     lt('discard relay')
32     log_discard(packet, iface, saddr, daddr, 'relay')
33   else:
34     lt('discard no-client')
35     log_discard(packet, iface, saddr, daddr, 'no-client')
36
37 #---------- client ----------
38
39 class Client():
40   def __init__(self, ip, cs, pw):
41     # instance data members
42     self._ip = ip
43     self._cs = cs
44     self.pw = pw
45     self._rq = collections.deque() # requests
46     # self._pq = PacketQueue(...)
47     # plus from config:
48     #  .max_batch_down
49     #  .max_queue_time
50     #  .max_request_time
51     #  .target_requests_outstanding
52
53     if ip not in c.network:
54       raise ValueError('client %s not in network' % ip)
55
56     for k in ('max_batch_down','max_queue_time','max_request_time',
57               'target_requests_outstanding'):
58       req = cfg.getint(cs, k)
59       limit = cfg.getint('limits',k)
60       self.__dict__[k] = min(req, limit)
61
62     self._pq = PacketQueue(str(ip), self.max_queue_time)
63
64     if ip in clients:
65       raise ValueError('multiple client cfg sections for %s' % ip)
66     clients[ip] = self
67
68     self._log(DBG.INIT, 'new')
69
70   def _log(self, dflag, msg, **kwargs):
71     log_debug(dflag, ('client %s: ' % self._ip)+msg, **kwargs)
72
73   def process_arriving_data(self, d):
74     self._log(DBG.FLOW, "req data (enc'd)", d=d)
75     if not len(d): return
76     for packet in slip.decode(d):
77       (saddr, daddr) = packet_addrs(packet)
78       if saddr != self._ip:
79         raise ValueError('wrong source address %s' % saddr)
80       route(packet, self._ip, saddr, daddr)
81
82   def _req_cancel(self, request):
83     self._log(DBG.HTTP_CTRL, 'cancel', idof=request)
84     request.finish()
85
86   def _req_error(self, err, request):
87     self._log(DBG.HTTP_CTRL, 'error %s' % err, idof=request)
88     self._req_cancel(request)
89
90   def queue_outbound(self, packet):
91     self._pq.append(packet)
92     self._check_outbound()
93
94   def new_request(self, request):
95     request.setHeader('Content-Type','application/octet-stream')
96     reactor.callLater(self.max_request_time, self._req_cancel, request)
97     request.notifyFinish().addErrback(self._req_error, request)
98     self._rq.append(request)
99     self._check_outbound()
100
101   def _check_outbound(self):
102     log_debug(DBG.HTTP_CTRL, 'CHKO')
103     while True:
104       try: request = self._rq[0]
105       except IndexError: request = None
106       if request and request.finished:
107         self._log(DBG.HTTP_CTRL, 'CHKO req finished, discard', idof=request)
108         self._rq.popleft()
109         continue
110
111       if not self._pq.nonempty():
112         # no packets, oh well
113         self._log(DBG.HTTP_CTRL, 'CHKO no packets, OUT-DONE', idof=request)
114         break
115
116       if request is None:
117         # no request
118         self._log(DBG.HTTP_CTRL, 'CHKO no request, OUT-DONE', idof=request)
119         break
120
121       self._log(DBG.HTTP_CTRL, 'CHKO processing', idof=request)
122       # request, and also some non-expired packets
123       self._pq.process((lambda: request.sentLength),
124                        request.write,
125                        self.max_batch_down)
126
127       assert(request.sentLength)
128       self._rq.popleft()
129       request.finish()
130       self._log(DBG.HTTP, 'complete', idof=request)
131       # round again, looking for more to do
132
133     while len(self._rq) > self.target_requests_outstanding:
134       request = self._rq.popleft()
135       self._log(DBG.HTTP, 'CHKO above target, returning empty', idof=request)
136       request.finish()
137
138 def process_request(request, desca):
139   # find client, update config, etc.
140   metadata = request.args[b'm'][0]
141   metadata = metadata.split(b'\r\n')
142   (ci_s, pw, tro) = metadata[0:3]
143   desca['m[0,2]'] = [ci_s, tro]
144   ci_s = ci_s.decode('utf-8')
145   tro = int(tro)
146   desca['tro']= tro
147   ci = ipaddr(ci_s)
148   desca['ci'] = ci
149   cl = clients[ci]
150   if pw != cl.pw: raise ValueError('bad password')
151   desca['pwok']=True
152
153   if tro != cl.target_requests_outstanding:
154     raise ValueError('tro must be %d' % cl.target_requests_outstanding)
155
156   try:
157     d = request.args[b'd'][0]
158     desca['d'] = d
159     desca['dlen'] = len(d)
160   except KeyError:
161     d = b''
162     desca['dlen'] = None
163
164   log_http(desca, 'processing', idof=id(request), d=d)
165
166   d = mime_translate(d)
167
168   cl.process_arriving_data(d)
169   cl.new_request(request)
170
171 def log_http(desca, msg, **kwargs):
172   try:
173     kwargs['d'] = desca['d']
174     del desca['d']
175   except KeyError:
176     pass
177   log_debug(DBG.HTTP, msg + repr(desca), **kwargs)
178
179 class IphttpResource(twisted.web.resource.Resource):
180   isLeaf = True
181   def render_POST(self, request):
182     log_debug(DBG.HTTP_FULL,
183               'req recv: ' + repr(request) + ' ' + repr(request.args),
184               idof=id(request))
185     desca = {'d': None}
186     try: process_request(request, desca)
187     except Exception as e:
188       emsg = traceback.format_exc()
189       log_http(desca, 'RETURNING EXCEPTION ' + emsg)
190       request.setHeader('Content-Type','text/plain; charset="utf-8"')
191       request.setResponseCode(400)
192       return (emsg + ' # ' + repr(desca) + '\r\n').encode('utf-8')
193     log_debug(DBG.HTTP_CTRL, '...', idof=id(request))
194     return NOT_DONE_YET
195
196   def render_GET(self, request):
197     log_debug(DBG.HTTP, 'GET request')
198     return b'<html><body>hippotat</body></html>'
199
200 def start_http():
201   resource = IphttpResource()
202   site = twisted.web.server.Site(resource)
203   for sa in c.saddrs:
204     ep = sa.make_endpoint()
205     crash_on_defer(ep.listen(site))
206     log_debug(DBG.INIT, 'listening on %s' % sa)
207
208 #---------- config and setup ----------
209         
210 def process_cfg():
211   process_cfg_common_always()
212   process_cfg_server()
213   process_cfg_network()
214
215   try:
216     c.relay = cfg.get('virtual','relay')
217   except NoOptionError:
218     for search in c.network.hosts():
219       if search == c.server: continue
220       c.relay = search
221       break
222
223   process_cfg_saddrs()
224   process_cfg_clients(Client)
225
226   process_cfg_ipif('server',
227                    (('local','server'),
228                     ('peer', 'relay'),
229                     ('rnets','network')))
230
231 common_startup()
232 process_cfg()
233 start_ipif(c.ipif_command, (lambda p,s,d: route(p,"[ipif]",s,d)))
234 start_http()
235 common_run()