4 signal.signal(signal.SIGINT, signal.SIG_DFL)
9 from twisted.internet import reactor
10 from twisted.logger import LogLevel
11 import twisted.internet.endpoints
14 from ipaddress import AddressValueError
16 from optparse import OptionParser
17 from configparser import ConfigParser
18 from configparser import NoOptionError
24 import hippotat.slip as slip
29 max_batch_down = 65536 # used by server, subject to [limits]
30 max_queue_time = 10 # used by server, subject to [limits]
31 max_request_time = 54 # used by server, subject to [limits]
32 target_requests_outstanding = 3 # must match; subject to [limits] on server
33 max_requests_outstanding = 4 # used by client
34 max_batch_up = 4000 # used by client
35 http_timeout = 30 # used by client
37 #[server] or [<client>] overrides
38 ipif = userv root ipif %(local)s,%(peer)s,%(mtu)s,slip %(rnets)s
39 # extra interpolations: %(local)s %(peer)s %(rnet)s
40 # obtained on server [virtual]server [virtual]relay [virtual]network
41 # from on client <client> [virtual]server [virtual]routes
46 # network = <prefix>/<len> # mandatory for server
47 # server = <ipaddr> # used by both, default is computed from `network'
48 # relay = <ipaddr> # used by server, default from `network' and `server'
49 # default server is first host in network
50 # default relay is first host which is not server
53 # addrs = 127.0.0.1 ::1 # mandatory for server
54 port = 80 # used by server
55 # url # used by client; default from first `addrs' and `port'
57 # [<client-ip4-or-ipv6-address>]
58 # password = <password> # used by both, must match
61 max_batch_down = 262144 # used by server
62 max_queue_time = 121 # used by server
63 max_request_time = 121 # used by server
64 target_requests_outstanding = 10 # used by server
67 # these need to be defined here so that they can be imported by import *
69 optparser = OptionParser()
71 _mimetrans = str.maketrans(b'-'+slip.esc, slip.esc+'-')
72 def mime_translate(s):
73 # SLIP-encoded packets cannot contain ESC ESC.
74 # Swap `-' and ESC. The result cannot contain `--'
75 return s.translate(_mimetrans)
78 def __init__(self, d = { }):
81 return 'ConfigResults('+repr(self.__dict__)+')'
85 def log_discard(packet, saddr, daddr, why):
86 print('DROP ', saddr, daddr, why)
87 # syslog.syslog(syslog.LOG_DEBUG,
88 # 'discarded packet %s -> %s (%s)' % (saddr, daddr, why))
90 #---------- packet parsing ----------
92 def packet_addrs(packet):
93 version = packet[0] >> 4
97 factory = ipaddress.IPv4Address
101 factory = ipaddress.IPv6Address
103 raise ValueError('unsupported IP version %d' % version)
104 saddr = factory(packet[ saddroff : saddroff + addrlen ])
105 daddr = factory(packet[ saddroff + addrlen : saddroff + addrlen*2 ])
106 return (saddr, daddr)
108 #---------- address handling ----------
112 r = ipaddress.IPv4Address(input)
113 except AddressValueError:
114 r = ipaddress.IPv6Address(input)
117 def ipnetwork(input):
119 r = ipaddress.IPv4Network(input)
120 except NetworkValueError:
121 r = ipaddress.IPv6Network(input)
124 #---------- ipif (SLIP) subprocess ----------
126 class SlipStreamDecoder():
127 def __init__(self, on_packet):
128 # we will call packet(<packet>)
130 self._on_packet = on_packet
132 def inputdata(self, data):
133 #print('SLIP-GOT ', repr(data))
135 packets = slip.decode(self._buffer)
136 self._buffer = packets.pop()
137 for packet in packets:
138 self._maybe_packet(packet)
140 def _maybe_packet(self, packet):
142 self._on_packet(packet)
145 self._maybe_packet(self._buffer)
148 class _IpifProcessProtocol(SlipProtocol):
149 def __init__(self, router):
150 self._router = router
151 self._decoder = SlipStreamDecoder(self.slip_on_packet)
152 def connectionMade(self): pass
153 def outReceived(self, data):
154 self._decoder.inputdata(data)
155 def slip_on_packet(self, packet):
156 (saddr, daddr) = packet_addrs(packet)
157 if saddr.is_link_local or daddr.is_link_local:
158 log_discard(packet, saddr, daddr, 'link-local')
160 self._router(packet, saddr, daddr)
161 def processEnded(self, status):
162 status.raiseException()
164 def start_ipif(command, router):
166 ipif = _IpifProcessProtocol(router)
167 reactor.spawnProcess(ipif,
168 '/bin/sh',['sh','-xc', command],
169 childFDs={0:'w', 1:'r', 2:2})
171 def queue_inbound(packet):
172 ipif.transport.write(slip.delimiter)
173 ipif.transport.write(slip.encode(packet))
174 ipif.transport.write(slip.delimiter)
176 #---------- packet queue ----------
179 def __init__(self, max_queue_time):
180 self._max_queue_time = max_queue_time
181 self._pq = collections.deque() # packets
183 def append(self, packet):
184 self._pq.append((time.monotonic(), packet))
188 try: (queuetime, packet) = self._pq[0]
189 except IndexError: return False
191 age = time.monotonic() - queuetime
192 if age > self.max_queue_time:
193 # strip old packets off the front
199 def process(self, sizequery, moredata, max_batch):
200 # sizequery() should return size of batch so far
201 # moredata(s) should add s to batch
203 try: (dummy, packet) = self._pq[0]
204 except IndexError: break
206 encoded = slip.encode(packet)
210 if sofar + len(slip.delimiter) + len(encoded) > max_batch:
212 moredata(slip.delimiter)
217 #---------- error handling ----------
220 print('CRASH ', err, file=sys.stderr)
222 except twisted.internet.error.ReactorNotRunning: pass
224 def crash_on_defer(defer):
225 defer.addErrback(lambda err: crash(err))
227 vdef crash_on_critical(event):
228 if event.get('log_level') >= LogLevel.critical:
229 crash(twisted.logger.formatEvent(event))
231 #---------- config processing ----------
233 def process_cfg_common_always():
235 c.mtu = cfg.get('virtual','mtu')
237 def process_cfg_ipif(section, varmap):
239 try: v = getattr(c, s)
240 except AttributeError: continue
245 c.ipif_command = cfg.get(section,'ipif', vars=c.__dict__)
247 def process_cfg_network():
248 c.network = ipnetwork(cfg.get('virtual','network'))
249 if c.network.num_addresses < 3 + 2:
250 raise ValueError('network needs at least 2^3 addresses')
252 def process_cfg_server():
254 c.server = cfg.get('virtual','server')
255 except NoOptionError:
256 process_cfg_network()
257 c.server = next(c.network.hosts())
260 def __init__(self, port, addrspec):
264 self.addr = ipaddress.IPv4Address(addrspec)
265 self._endpointfactory = twisted.internet.endpoints.TCP4ServerEndpoint
267 except AddressValueError:
268 self.addr = ipaddress.IPv6Address(addrspec)
269 self._endpointfactory = twisted.internet.endpoints.TCP6ServerEndpoint
271 def make_endpoint(self):
272 return self._endpointfactory(reactor, self.port, self.addr)
274 url = 'http://' + (self._inurl % self.addr)
275 if self.port != 80: url += ':%d' % self.port
279 def process_cfg_saddrs():
280 try: port = cfg.getint('server','port')
281 except NoOptionError: port = 80
284 for addrspec in cfg.get('server','addrs').split():
285 sa = ServerAddr(port, addrspec)
288 def process_cfg_clients(constructor):
290 for cs in cfg.sections():
291 if not (':' in cs or '.' in cs): continue
293 pw = cfg.get(cs, 'password')
294 constructor(ci,cs,pw)
296 #---------- startup ----------
298 def common_startup():
299 twisted.logger.globalLogPublisher.addObserver(crash_on_critical)
301 optparser.add_option('-c', '--config', dest='configfile',
302 default='/etc/hippotat/config')
303 (opts, args) = optparser.parse_args()
304 if len(args): optparser.error('no non-option arguments please')
306 re = regexp.compile('#.*')
307 cfg.read_string(re.sub('', defcfg))
308 cfg.read(opts.configfile)
312 print('CRASHED (end)', file=sys.stderr)