4 ### Service for automatically tracking network connection status
6 ### (c) 2010 Straylight/Edgeware
9 ###----- Licensing notice ---------------------------------------------------
11 ### This file is part of Trivial IP Encryption (TrIPE).
13 ### TrIPE is free software; you can redistribute it and/or modify
14 ### it under the terms of the GNU General Public License as published by
15 ### the Free Software Foundation; either version 2 of the License, or
16 ### (at your option) any later version.
18 ### TrIPE 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
21 ### GNU General Public License for more details.
23 ### You should have received a copy of the GNU General Public License
24 ### along with TrIPE; if not, write to the Free Software Foundation,
25 ### Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
29 ###--------------------------------------------------------------------------
30 ### External dependencies.
32 from ConfigParser import RawConfigParser
33 from optparse import OptionParser
40 for i in ['mainloop', 'mainloop.glib']:
41 __import__('dbus.%s' % i)
43 from struct import pack, unpack
46 ##__import__('rmcr').__debug = True
48 ###--------------------------------------------------------------------------
51 class struct (object):
52 """A simple container object."""
53 def __init__(me, **kw):
54 me.__dict__.update(kw)
56 def toposort(cmp, things):
58 Generate the THINGS in an order consistent with a given partial order.
60 The function CMP(X, Y) should return true if X must precede Y, and false if
61 it doesn't care. If X and Y are equal then it should return false.
63 The THINGS may be any finite iterable; it is converted to a list
67 ## Make sure we can index the THINGS, and prepare an ordering table.
68 ## What's going on? The THINGS might not have a helpful equality
69 ## predicate, so it's easier to work with indices. The ordering table will
70 ## remember which THINGS (by index) are considered greater than other
74 order = [{} for i in xrange(n)]
75 rorder = [{} for i in xrange(n)]
78 if i != j and cmp(things[i], things[j]):
82 ## Now we can do the sort.
87 if order[i] is not None:
89 if len(order[i]) == 0:
97 ###--------------------------------------------------------------------------
98 ### Parse the configuration file.
100 ## Hmm. Should I try to integrate this with the peers database? It's not a
101 ## good fit; it'd need special hacks in tripe-newpeers. And the use case for
102 ## this service are largely going to be satellite notes, I don't think
103 ## scalability's going to be a problem.
105 class Config (object):
107 Represents a configuration file.
109 The most interesting thing is probably the `groups' slot, which stores a
110 list of pairs (NAME, PATTERNS); the NAME is a string, and the PATTERNS a
111 list of (TAG, PEER, ADDR, MASK) triples. The implication is that there
112 should be precisely one peer with a name matching NAME-*, and that it
113 should be NAME-TAG, where (TAG, PEER, ADDR, MASK) is the first triple such
114 that the host's primary IP address (if PEER is None -- or the IP address it
115 would use for communicating with PEER) is within the network defined by
119 def __init__(me, file):
121 Construct a new Config object, reading the given FILE.
124 me._fwatch = M.FWatch(file)
129 See whether the configuration file has been updated.
131 if me._fwatch.update():
136 Internal function to update the configuration from the underlying file.
139 ## Read the configuration. We have no need of the fancy substitutions,
140 ## so turn them all off.
141 cp = RawConfigParser()
144 ## Save the test address. Make sure it's vaguely sensible. The default
145 ## is probably good for most cases, in fact, since that address isn't
146 ## actually in use. Note that we never send packets to the test address;
147 ## we just use it to discover routing information.
148 if cp.has_option('DEFAULT', 'test-addr'):
149 testaddr = cp.get('DEFAULT', 'test-addr')
150 S.inet_aton(testaddr)
154 ## Scan the configuration file and build the groups structure.
156 for sec in cp.sections():
158 for tag in cp.options(sec):
159 spec = cp.get(sec, tag).split()
161 ## Parse the entry into peer and network.
168 ## Syntax of a net is ADDRESS/MASK, where ADDRESS is a dotted-quad,
169 ## and MASK is either a dotted-quad or a single integer N indicating
170 ## a mask with N leading ones followed by trailing zeroes.
171 slash = net.index('/')
172 addr, = unpack('>L', S.inet_aton(net[:slash]))
173 if net.find('.', slash + 1) >= 0:
174 mask, = unpack('>L', S.inet_aton(net[:slash]))
176 n = int(net[slash + 1:], 10)
177 mask = (1 << 32) - (1 << 32 - n)
178 pats.append((tag, peer, addr & mask, mask))
180 ## Annoyingly, RawConfigParser doesn't preserve the order of options.
181 ## In order to make things vaguely sane, we topologically sort the
182 ## patterns so that more specific patterns are checked first.
183 pats = list(toposort(lambda (t, p, a, m), (tt, pp, aa, mm): \
185 (p == pp and m == (m | mm) and aa == (a & mm)),
187 groups.append((sec, pats))
190 me.testaddr = testaddr
193 ### This will be a configuration file.
196 ###--------------------------------------------------------------------------
197 ### Responding to a network up/down event.
201 Return the local IP address used for talking to PEER.
203 sk = S.socket(S.AF_INET, S.SOCK_DGRAM)
206 sk.connect((peer, 1))
207 addr, _ = sk.getsockname()
208 addr, = unpack('>L', S.inet_aton(addr))
219 upness, reason = _kick.get()
221 ## Make sure the configuration file is up-to-date. Don't worry if we
222 ## can't do anything useful.
225 except Exception, exc:
226 SM.warn('conntrack', 'config-file-error',
227 exc.__class__.__name__, str(exc))
229 ## Find the current list of peers.
232 ## Work out the primary IP address.
234 addr = localaddr(CF.testaddr)
240 ## Now decide what to do.
242 for g, pp in CF.groups:
244 ## Find out which peer in the group ought to be active.
248 for t, p, a, m in pp:
249 if p is None or not upness:
253 if upness and ip is None and \
254 ipq is not None and (ipq & m) == a:
261 ## Shut down the wrong ones.
264 what = map.get(p, 'leave')
268 changes.append(lambda p=p: SM.kill(p))
270 ## Start the right one if necessary.
271 if want is not None and (not found or ip != lastip.get(g, None)):
272 changes.append(lambda: T._simple(SM.svcsubmit('connect', 'active',
276 ## Commit the changes.
278 SM.notify('conntrack', upness and 'up' or 'down', *reason)
279 for c in changes: c()
281 def netupdown(upness, reason):
283 Add or kill peers according to whether the network is up or down.
285 UPNESS is true if the network is up, or false if it's down.
288 _kick.put((upness, reason))
290 ###--------------------------------------------------------------------------
291 ### NetworkManager monitor.
293 NM_NAME = 'org.freedesktop.NetworkManager'
294 NM_PATH = '/org/freedesktop/NetworkManager'
296 NMCA_IFACE = NM_NAME + '.Connection.Active'
298 NM_STATE_CONNECTED = 3
300 class NetworkManagerMonitor (object):
302 Watch NetworkManager signals for changes in network state.
305 ## Strategy. There are two kinds of interesting state transitions for us.
306 ## The first one is the global are-we-connected state, which we'll use to
307 ## toggle network upness on a global level. The second is which connection
308 ## has the default route, which we'll use to tweak which peer in the peer
309 ## group is active. The former is most easily tracked using the signal
310 ## org.freedesktop.NetworkManager.StateChanged; for the latter, we track
311 ## org.freedesktop.NetworkManager.Connection.Active.PropertiesChanged and
312 ## look for when a new connection gains the default route.
316 nm = bus.get_object(NM_NAME, NM_PATH)
317 state = nm.Get(NM_IFACE, 'State')
318 if state == NM_STATE_CONNECTED:
319 netupdown(True, ['nm', 'initially-connected'])
321 netupdown(False, ['nm', 'initially-disconnected'])
322 except D.DBusException:
324 bus.add_signal_receiver(me._nm_state, 'StateChanged', NM_IFACE,
326 bus.add_signal_receiver(me._nm_connchange,
327 'PropertiesChanged', NMCA_IFACE,
330 def _nm_state(me, state):
331 if state == NM_STATE_CONNECTED:
332 netupdown(True, ['nm', 'connected'])
334 netupdown(False, ['nm', 'disconnected'])
336 def _nm_connchange(me, props):
337 if props.get('Default', False):
338 netupdown(True, ['nm', 'default-connection-change'])
340 ###--------------------------------------------------------------------------
343 ICD_NAME = 'com.nokia.icd'
344 ICD_PATH = '/com/nokia/icd'
347 class MaemoICdMonitor (object):
349 Watch ICd signals for changes in network state.
352 ## Strategy. ICd only handles one connection at a time in steady state,
353 ## though when switching between connections, it tries to bring the new one
354 ## up before shutting down the old one. This makes life a bit easier than
355 ## it is with NetworkManager. On the other hand, the notifications are
356 ## relative to particular connections only, and the indicator that the old
357 ## connection is down (`IDLE') comes /after/ the new one comes up
358 ## (`CONNECTED'), so we have to remember which one is active.
362 icd = bus.get_object(ICD_NAME, ICD_PATH)
364 iap = icd.get_ipinfo(dbus_interface = ICD_IFACE)[0]
366 netupdown(True, ['icd', 'initially-connected', iap])
367 except D.DBusException:
369 netupdown(False, ['icd', 'initially-disconnected'])
370 except D.DBusException:
372 bus.add_signal_receiver(me._icd_state, 'status_changed', ICD_IFACE,
375 def _icd_state(me, iap, ty, state, hunoz):
376 if state == 'CONNECTED':
378 netupdown(True, ['icd', 'connected', iap])
379 elif state == 'IDLE' and iap == me._iap:
381 netupdown(False, ['icd', 'idle'])
383 ###--------------------------------------------------------------------------
384 ### D-Bus connection tracking.
386 class DBusMonitor (object):
388 Maintains a connection to the system D-Bus, and watches for signals.
390 If the connection is initially down, or drops for some reason, we retry
391 periodically (every five seconds at the moment). If the connection
392 resurfaces, we reattach the monitors.
397 Initialise the object and try to establish a connection to the bus.
400 me._loop = D.mainloop.glib.DBusGMainLoop()
401 me._state = 'startup'
406 Add a monitor object to watch for signals.
408 MON.attach(BUS) is called, with BUS being the connection to the system
409 bus. MON should query its service's current status and watch for
413 if me._bus is not None:
416 def _reconnect(me, hunoz = None):
418 Start connecting to the bus.
420 If we fail the first time, retry periodically.
422 if me._state == 'startup':
423 T.aside(SM.notify, 'conntrack', 'dbus-connection', 'startup')
424 elif me._state == 'connected':
425 T.aside(SM.notify, 'conntrack', 'dbus-connection', 'lost')
427 T.aside(SM.notify, 'conntrack', 'dbus-connection',
428 'state=%s' % me._state)
429 me._state == 'reconnecting'
431 if me._try_connect():
432 G.timeout_add_seconds(5, me._try_connect)
434 def _try_connect(me):
436 Actually make a connection attempt.
438 If we succeed, attach the monitors.
441 addr = OS.getenv('TRIPE_CONNTRACK_BUS')
442 if addr == 'SESSION':
443 bus = D.SessionBus(mainloop = me._loop, private = True)
444 elif addr is not None:
445 bus = D.bus.BusConnection(addr, mainloop = me._loop)
447 bus = D.SystemBus(mainloop = me._loop, private = True)
450 except D.DBusException, e:
453 me._state = 'connected'
454 bus.call_on_disconnection(me._reconnect)
455 T.aside(SM.notify, 'conntrack', 'dbus-connection', 'connected')
458 ###--------------------------------------------------------------------------
461 class GIOWatcher (object):
463 Monitor I/O events using glib.
465 def __init__(me, conn, mc = G.main_context_default()):
469 def connected(me, sock):
470 me._watch = G.io_add_watch(sock, G.IO_IN,
471 lambda *hunoz: me._conn.receive())
472 def disconnected(me):
473 G.source_remove(me._watch)
476 me._mc.iteration(True)
478 SM.iowatch = GIOWatcher(SM)
482 Service initialization.
484 Add the D-Bus monitor here, because we might send commands off immediately,
485 and we want to make sure the server connection is up.
488 T.Coroutine(kickpeers, name = 'kickpeers').switch()
490 DBM.addmon(NetworkManagerMonitor())
491 DBM.addmon(MaemoICdMonitor())
492 G.timeout_add_seconds(30, lambda: (netupdown(True, ['interval-timer'])
497 Parse the command-line options.
499 Automatically changes directory to the requested configdir, and turns on
500 debugging. Returns the options object.
502 op = OptionParser(usage = '%prog [-a FILE] [-d DIR]',
503 version = '%%prog %s' % VERSION)
505 op.add_option('-a', '--admin-socket',
506 metavar = 'FILE', dest = 'tripesock', default = T.tripesock,
507 help = 'Select socket to connect to [default %default]')
508 op.add_option('-d', '--directory',
509 metavar = 'DIR', dest = 'dir', default = T.configdir,
510 help = 'Select current diretory [default %default]')
511 op.add_option('-c', '--config',
512 metavar = 'FILE', dest = 'conf', default = 'conntrack.conf',
513 help = 'Select configuration [default %default]')
514 op.add_option('--daemon', dest = 'daemon',
515 default = False, action = 'store_true',
516 help = 'Become a daemon after successful initialization')
517 op.add_option('--debug', dest = 'debug',
518 default = False, action = 'store_true',
519 help = 'Emit debugging trace information')
520 op.add_option('--startup', dest = 'startup',
521 default = False, action = 'store_true',
522 help = 'Being called as part of the server startup')
524 opts, args = op.parse_args()
525 if args: op.error('no arguments permitted')
527 T._debug = opts.debug
530 ## Service table, for running manually.
531 def cmd_updown(upness):
532 return lambda *args: T.defer(netupdown, upness, ['manual'] + list(args))
533 service_info = [('conntrack', VERSION, {
534 'up': (0, None, '', cmd_updown(True)),
535 'down': (0, None, '', cmd_updown(False))
538 if __name__ == '__main__':
539 opts = parse_options()
540 CF = Config(opts.conf)
541 T.runservices(opts.tripesock, service_info,
542 init = init, daemon = opts.daemon)
544 ###----- That's all, folks --------------------------------------------------