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a62f8e8a MW |
1 | #! @PYTHON@ |
2 | ### -*-python-*- | |
3 | ### | |
d64ce4ae | 4 | ### Connect to remote peers, and keep track of them |
a62f8e8a | 5 | ### |
d64ce4ae | 6 | ### (c) 2007 Straylight/Edgeware |
a62f8e8a MW |
7 | ### |
8 | ||
9 | ###----- Licensing notice --------------------------------------------------- | |
10 | ### | |
11 | ### This file is part of Trivial IP Encryption (TrIPE). | |
12 | ### | |
11ad66c2 MW |
13 | ### TrIPE is free software: you can redistribute it and/or modify it under |
14 | ### the terms of the GNU General Public License as published by the Free | |
15 | ### Software Foundation; either version 3 of the License, or (at your | |
16 | ### option) any later version. | |
a62f8e8a | 17 | ### |
11ad66c2 MW |
18 | ### TrIPE is distributed in the hope that it will be useful, but WITHOUT |
19 | ### ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
20 | ### FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
21 | ### for more details. | |
a62f8e8a MW |
22 | ### |
23 | ### You should have received a copy of the GNU General Public License | |
11ad66c2 | 24 | ### along with TrIPE. If not, see <https://www.gnu.org/licenses/>. |
a62f8e8a MW |
25 | |
26 | VERSION = '@VERSION@' | |
27 | ||
28 | ###-------------------------------------------------------------------------- | |
29 | ### External dependencies. | |
30 | ||
31 | from optparse import OptionParser | |
32 | import tripe as T | |
33 | import os as OS | |
d64ce4ae MW |
34 | import signal as SIG |
35 | import errno as E | |
b9dedfa6 | 36 | from math import sqrt |
a62f8e8a MW |
37 | import cdb as CDB |
38 | import mLib as M | |
d64ce4ae | 39 | import re as RX |
a62f8e8a | 40 | from time import time |
d64ce4ae | 41 | import subprocess as PROC |
a62f8e8a MW |
42 | |
43 | S = T.svcmgr | |
44 | ||
45 | ###-------------------------------------------------------------------------- | |
d64ce4ae MW |
46 | ### Running auxiliary commands. |
47 | ||
48 | class SelLineQueue (M.SelLineBuffer): | |
49 | """Glues the select-line-buffer into the coroutine queue system.""" | |
50 | ||
51 | def __new__(cls, file, queue, tag, kind): | |
52 | """See __init__ for documentation.""" | |
53 | return M.SelLineBuffer.__new__(cls, file.fileno()) | |
54 | ||
55 | def __init__(me, file, queue, tag, kind): | |
56 | """ | |
57 | Initialize a new line-reading adaptor. | |
58 | ||
59 | The adaptor reads lines from FILE. Each line is inserted as a message of | |
60 | the stated KIND, bearing the TAG, into the QUEUE. End-of-file is | |
61 | represented as None. | |
62 | """ | |
63 | me._q = queue | |
64 | me._file = file | |
65 | me._tag = tag | |
66 | me._kind = kind | |
67 | me.enable() | |
68 | ||
69 | @T._callback | |
70 | def line(me, line): | |
71 | me._q.put((me._tag, me._kind, line)) | |
72 | ||
73 | @T._callback | |
74 | def eof(me): | |
75 | me.disable() | |
76 | me._q.put((me._tag, me._kind, None)) | |
77 | ||
78 | class ErrorWatch (T.Coroutine): | |
79 | """ | |
80 | An object which watches stderr streams for errors and converts them into | |
81 | warnings of the form | |
82 | ||
83 | WARN connect INFO stderr LINE | |
84 | ||
85 | The INFO is a list of tokens associated with the file when it was | |
86 | registered. | |
87 | ||
88 | Usually there is a single ErrorWatch object, called errorwatch. | |
89 | """ | |
90 | ||
91 | def __init__(me): | |
92 | """Initialization: there are no arguments.""" | |
93 | T.Coroutine.__init__(me) | |
94 | me._q = T.Queue() | |
95 | me._map = {} | |
96 | me._seq = 1 | |
97 | ||
98 | def watch(me, file, info): | |
99 | """ | |
100 | Adds FILE to the collection of files to watch. | |
101 | ||
102 | INFO will be written in the warning messages from this FILE. Returns a | |
103 | sequence number which can be used to unregister the file again. | |
104 | """ | |
105 | seq = me._seq | |
106 | me._seq += 1 | |
107 | me._map[seq] = info, SelLineQueue(file, me._q, seq, 'stderr') | |
108 | return seq | |
109 | ||
110 | def unwatch(me, seq): | |
111 | """Stop watching the file with sequence number SEQ.""" | |
112 | del me._map[seq] | |
113 | return me | |
114 | ||
115 | def run(me): | |
116 | """ | |
117 | Coroutine function: read items from the queue and report them. | |
118 | ||
119 | Unregisters files automatically when they reach EOF. | |
120 | """ | |
121 | while True: | |
122 | seq, _, line = me._q.get() | |
123 | if line is None: | |
124 | me.unwatch(seq) | |
125 | else: | |
126 | S.warn(*['connect'] + me._map[seq][0] + ['stderr', line]) | |
127 | ||
128 | def dbwatch(): | |
129 | """ | |
14b77b60 | 130 | Coroutine function: wake up every minute and notice changes to the |
d64ce4ae MW |
131 | database. When a change happens, tell the Pinger (q.v.) to rescan its |
132 | peers. | |
133 | """ | |
134 | cr = T.Coroutine.getcurrent() | |
135 | main = cr.parent | |
136 | fw = M.FWatch(opts.cdb) | |
137 | while True: | |
14b77b60 | 138 | timer = M.SelTimer(time() + 60, lambda: cr.switch()) |
d64ce4ae MW |
139 | main.switch() |
140 | if fw.update(): | |
141 | pinger.rescan(False) | |
142 | S.notify('connect', 'peerdb-update') | |
143 | ||
144 | class ChildWatch (M.SelSignal): | |
145 | """ | |
146 | An object which watches for specified processes exiting and reports | |
147 | terminations by writing items of the form (TAG, 'exit', RESULT) to a queue. | |
148 | ||
149 | There is usually only one ChildWatch object, called childwatch. | |
150 | """ | |
151 | ||
152 | def __new__(cls): | |
153 | """Initialize the child-watcher.""" | |
154 | return M.SelSignal.__new__(cls, SIG.SIGCHLD) | |
155 | ||
156 | def __init__(me): | |
157 | """Initialize the child-watcher.""" | |
158 | me._pid = {} | |
159 | me.enable() | |
160 | ||
161 | def watch(me, pid, queue, tag): | |
162 | """ | |
163 | Register PID as a child to watch. If it exits, write (TAG, 'exit', CODE) | |
164 | to the QUEUE, where CODE is one of | |
165 | ||
166 | * None (successful termination) | |
167 | * ['exit-nonzero', CODE] (CODE is a string!) | |
168 | * ['exit-signal', 'S' + CODE] (CODE is the signal number as a string) | |
169 | * ['exit-unknown', STATUS] (STATUS is the entire exit status, in hex) | |
170 | """ | |
171 | me._pid[pid] = queue, tag | |
172 | return me | |
173 | ||
174 | def unwatch(me, pid): | |
175 | """Unregister PID as a child to watch.""" | |
176 | del me._pid[pid] | |
177 | return me | |
178 | ||
179 | @T._callback | |
180 | def signalled(me): | |
181 | """ | |
182 | Called when child processes exit: collect exit statuses and report | |
183 | failures. | |
184 | """ | |
185 | while True: | |
186 | try: | |
187 | pid, status = OS.waitpid(-1, OS.WNOHANG) | |
188 | except OSError, exc: | |
189 | if exc.errno == E.ECHILD: | |
190 | break | |
191 | if pid == 0: | |
192 | break | |
193 | if pid not in me._pid: | |
194 | continue | |
195 | queue, tag = me._pid[pid] | |
196 | if OS.WIFEXITED(status): | |
197 | exit = OS.WEXITSTATUS(status) | |
198 | if exit == 0: | |
199 | code = None | |
200 | else: | |
201 | code = ['exit-nonzero', str(exit)] | |
202 | elif OS.WIFSIGNALED(status): | |
203 | code = ['exit-signal', 'S' + str(OS.WTERMSIG(status))] | |
204 | else: | |
205 | code = ['exit-unknown', hex(status)] | |
206 | queue.put((tag, 'exit', code)) | |
207 | ||
208 | class Command (object): | |
209 | """ | |
210 | Represents a running command. | |
211 | ||
212 | This class is the main interface to the machery provided by the ChildWatch | |
213 | and ErrorWatch objects. See also potwatch. | |
214 | """ | |
215 | ||
216 | def __init__(me, info, queue, tag, args, env): | |
217 | """ | |
218 | Start a new child process. | |
219 | ||
220 | The ARGS are a list of arguments to be given to the child process. The | |
221 | ENV is either None or a dictionary of environment variable assignments to | |
222 | override the extant environment. INFO is a list of tokens to be included | |
223 | in warnings about the child's stderr output. If the child writes a line | |
224 | to standard output, put (TAG, 'stdout', LINE) to the QUEUE. When the | |
225 | child exits, write (TAG, 'exit', CODE) to the QUEUE. | |
226 | """ | |
227 | me._info = info | |
228 | me._q = queue | |
229 | me._tag = tag | |
230 | myenv = OS.environ.copy() | |
231 | if env: myenv.update(env) | |
232 | me._proc = PROC.Popen(args = args, env = myenv, bufsize = 1, | |
233 | stdout = PROC.PIPE, stderr = PROC.PIPE) | |
234 | me._lq = SelLineQueue(me._proc.stdout, queue, tag, 'stdout') | |
235 | errorwatch.watch(me._proc.stderr, info) | |
236 | childwatch.watch(me._proc.pid, queue, tag) | |
237 | ||
238 | def __del__(me): | |
239 | """ | |
240 | If I've been forgotten then stop watching for termination. | |
241 | """ | |
242 | childwatch.unwatch(me._proc.pid) | |
243 | ||
244 | def potwatch(what, name, q): | |
245 | """ | |
246 | Watch the queue Q for activity as reported by a Command object. | |
247 | ||
248 | Information from the process's stdout is reported as | |
249 | ||
250 | NOTE WHAT NAME stdout LINE | |
251 | ||
252 | abnormal termination is reported as | |
253 | ||
254 | WARN WHAT NAME CODE | |
255 | ||
256 | where CODE is what the ChildWatch wrote. | |
257 | """ | |
258 | eofp = deadp = False | |
259 | while not deadp or not eofp: | |
260 | _, kind, more = q.get() | |
261 | if kind == 'stdout': | |
262 | if more is None: | |
263 | eofp = True | |
264 | else: | |
265 | S.notify('connect', what, name, 'stdout', more) | |
266 | elif kind == 'exit': | |
267 | if more: S.warn('connect', what, name, *more) | |
268 | deadp = True | |
269 | ||
270 | ###-------------------------------------------------------------------------- | |
271 | ### Peer database utilities. | |
a62f8e8a MW |
272 | |
273 | _magic = ['_magic'] # An object distinct from all others | |
274 | ||
275 | class Peer (object): | |
276 | """Representation of a peer in the database.""" | |
277 | ||
278 | def __init__(me, peer, cdb = None): | |
279 | """ | |
280 | Create a new peer, named PEER. | |
281 | ||
282 | Information about the peer is read from the database CDB, or the default | |
283 | one given on the command-line. | |
284 | """ | |
285 | me.name = peer | |
d64ce4ae | 286 | record = (cdb or CDB.init(opts.cdb))['P' + peer] |
a62f8e8a MW |
287 | me.__dict__.update(M.URLDecode(record, semip = True)) |
288 | ||
d64ce4ae | 289 | def get(me, key, default = _magic, filter = None): |
a62f8e8a MW |
290 | """ |
291 | Get the information stashed under KEY from the peer's database record. | |
292 | ||
293 | If DEFAULT is given, then use it if the database doesn't contain the | |
d64ce4ae MW |
294 | necessary information. If no DEFAULT is given, then report an error. If |
295 | a FILTER function is given then apply it to the information from the | |
296 | database before returning it. | |
a62f8e8a MW |
297 | """ |
298 | attr = me.__dict__.get(key, default) | |
299 | if attr is _magic: | |
300 | raise T.TripeJobError('malformed-peer', me.name, 'missing-key', key) | |
d64ce4ae MW |
301 | elif filter is not None: |
302 | attr = filter(attr) | |
a62f8e8a MW |
303 | return attr |
304 | ||
d64ce4ae MW |
305 | def has(me, key): |
306 | """ | |
307 | Return whether the peer's database record has the KEY. | |
308 | """ | |
309 | return key in me.__dict__ | |
310 | ||
a62f8e8a MW |
311 | def list(me): |
312 | """ | |
313 | Iterate over the available keys in the peer's database record. | |
314 | """ | |
315 | return me.__dict__.iterkeys() | |
316 | ||
d64ce4ae MW |
317 | def boolean(value): |
318 | """Parse VALUE as a boolean.""" | |
319 | return value in ['t', 'true', 'y', 'yes', 'on'] | |
320 | ||
321 | ###-------------------------------------------------------------------------- | |
322 | ### Waking up and watching peers. | |
323 | ||
324 | def run_connect(peer, cmd): | |
325 | """ | |
326 | Start the job of connecting to the passive PEER. | |
327 | ||
328 | The CMD string is a shell command which will connect to the peer (via some | |
329 | back-channel, say ssh and userv), issue a command | |
330 | ||
331 | SVCSUBMIT connect passive [OPTIONS] USER | |
332 | ||
333 | and write the resulting challenge to standard error. | |
334 | """ | |
335 | q = T.Queue() | |
336 | cmd = Command(['connect', peer.name], q, 'connect', | |
337 | ['/bin/sh', '-c', cmd], None) | |
338 | _, kind, more = q.peek() | |
339 | if kind == 'stdout': | |
340 | if more is None: | |
341 | S.warn('connect', 'connect', peer.name, 'unexpected-eof') | |
342 | else: | |
343 | chal = more | |
344 | S.greet(peer.name, chal) | |
345 | q.get() | |
346 | potwatch('connect', peer.name, q) | |
347 | ||
348 | def run_disconnect(peer, cmd): | |
349 | """ | |
350 | Start the job of disconnecting from a passive PEER. | |
351 | ||
352 | The CMD string is a shell command which will disconnect from the peer. | |
353 | """ | |
354 | q = T.Queue() | |
355 | cmd = Command(['disconnect', peer.name], q, 'disconnect', | |
356 | ['/bin/sh', '-c', cmd], None) | |
357 | potwatch('disconnect', peer.name, q) | |
358 | ||
359 | _pingseq = 0 | |
360 | class PingPeer (object): | |
361 | """ | |
362 | Object representing a peer which we are pinging to ensure that it is still | |
363 | present. | |
364 | ||
365 | PingPeer objects are held by the Pinger (q.v.). The Pinger maintains an | |
366 | event queue -- which saves us from having an enormous swarm of coroutines | |
367 | -- but most of the actual work is done here. | |
368 | ||
369 | In order to avoid confusion between different PingPeer instances for the | |
370 | same actual peer, each PingPeer has a sequence number (its `seq' | |
371 | attribute). Events for the PingPeer are identified by a (PEER, SEQ) pair. | |
372 | (Using the PingPeer instance itself will prevent garbage collection of | |
373 | otherwise defunct instances.) | |
374 | """ | |
375 | ||
376 | def __init__(me, pinger, queue, peer, pingnow): | |
377 | """ | |
378 | Create a new PingPeer. | |
379 | ||
380 | The PINGER is the Pinger object we should send the results to. This is | |
381 | used when we remove ourselves, if the peer has been explicitly removed. | |
382 | ||
383 | The QUEUE is the event queue on which timer and ping-command events | |
384 | should be written. | |
385 | ||
386 | The PEER is a `Peer' object describing the peer. | |
387 | ||
388 | If PINGNOW is true, then immediately start pinging the peer. Otherwise | |
389 | wait until the usual retry interval. | |
390 | """ | |
391 | global _pingseq | |
392 | me._pinger = pinger | |
393 | me._q = queue | |
394 | me._peer = peer.name | |
395 | me.update(peer) | |
396 | me.seq = _pingseq | |
397 | _pingseq += 1 | |
398 | me._failures = 0 | |
965eb987 | 399 | me._sabotage = False |
b9dedfa6 MW |
400 | me._last = '-' |
401 | me._nping = 0 | |
402 | me._nlost = 0 | |
403 | me._sigma_t = 0 | |
404 | me._sigma_t2 = 0 | |
405 | me._min = me._max = '-' | |
d64ce4ae MW |
406 | if pingnow: |
407 | me._timer = None | |
408 | me._ping() | |
409 | else: | |
410 | me._timer = M.SelTimer(time() + me._every, me._time) | |
411 | ||
412 | def update(me, peer): | |
413 | """ | |
414 | Refreshes the timer parameters for this peer. We don't, however, | |
415 | immediately reschedule anything: that will happen next time anything | |
416 | interesting happens. | |
417 | """ | |
418 | if peer is None: peer = Peer(me._peer) | |
419 | assert peer.name == me._peer | |
420 | me._every = peer.get('every', filter = T.timespec, default = 120) | |
421 | me._timeout = peer.get('timeout', filter = T.timespec, default = 10) | |
422 | me._retries = peer.get('retries', filter = int, default = 5) | |
423 | me._connectp = peer.has('connect') | |
424 | return me | |
425 | ||
426 | def _ping(me): | |
427 | """ | |
428 | Send a ping to the peer; the result is sent to the Pinger's event queue. | |
429 | """ | |
430 | S.rawcommand(T.TripeAsynchronousCommand( | |
431 | me._q, (me._peer, me.seq), | |
432 | ['EPING', | |
433 | '-background', S.bgtag(), | |
434 | '-timeout', str(me._timeout), | |
435 | '--', | |
436 | me._peer])) | |
437 | ||
438 | def _reconnect(me): | |
439 | peer = Peer(me._peer) | |
440 | if me._connectp: | |
441 | S.warn('connect', 'reconnecting', me._peer) | |
442 | S.forcekx(me._peer) | |
443 | T.spawn(run_connect, peer, peer.get('connect')) | |
444 | me._timer = M.SelTimer(time() + me._every, me._time) | |
965eb987 | 445 | me._sabotage = False |
d64ce4ae MW |
446 | else: |
447 | S.kill(me._peer) | |
448 | ||
449 | def event(me, code, stuff): | |
450 | """ | |
451 | Respond to an event which happened to this peer. | |
452 | ||
453 | Timer events indicate that we should start a new ping. (The server has | |
454 | its own timeout which detects lost packets.) | |
455 | ||
456 | We trap unknown-peer responses and detach from the Pinger. | |
457 | ||
458 | If the ping fails and we run out of retries, we attempt to restart the | |
459 | connection. | |
460 | """ | |
461 | if code == 'TIMER': | |
462 | me._failures = 0 | |
463 | me._ping() | |
464 | elif code == 'FAIL': | |
465 | S.notify('connect', 'ping-failed', me._peer, *stuff) | |
466 | if not stuff: | |
467 | pass | |
468 | elif stuff[0] == 'unknown-peer': | |
469 | me._pinger.kill(me._peer) | |
470 | elif stuff[0] == 'ping-send-failed': | |
471 | me._reconnect() | |
472 | elif code == 'INFO': | |
965eb987 MW |
473 | outcome = stuff[0] |
474 | if outcome == 'ping-ok' and me._sabotage: | |
475 | outcome = 'ping-timeout' | |
476 | if outcome == 'ping-ok': | |
d64ce4ae MW |
477 | if me._failures > 0: |
478 | S.warn('connect', 'ping-ok', me._peer) | |
b9dedfa6 MW |
479 | t = float(stuff[1]) |
480 | me._last = '%.1fms' % t | |
481 | me._sigma_t += t | |
482 | me._sigma_t2 += t*t | |
483 | me._nping += 1 | |
484 | if me._min == '-' or t < me._min: me._min = t | |
485 | if me._max == '-' or t > me._max: me._max = t | |
d64ce4ae | 486 | me._timer = M.SelTimer(time() + me._every, me._time) |
965eb987 | 487 | elif outcome == 'ping-timeout': |
d64ce4ae | 488 | me._failures += 1 |
b9dedfa6 | 489 | me._nlost += 1 |
d64ce4ae MW |
490 | S.warn('connect', 'ping-timeout', me._peer, |
491 | 'attempt', str(me._failures), 'of', str(me._retries)) | |
492 | if me._failures < me._retries: | |
493 | me._ping() | |
b9dedfa6 | 494 | me._last = 'timeout' |
d64ce4ae MW |
495 | else: |
496 | me._reconnect() | |
965eb987 MW |
497 | me._last = 'reconnect' |
498 | elif outcome == 'ping-peer-died': | |
d64ce4ae MW |
499 | me._pinger.kill(me._peer) |
500 | ||
965eb987 MW |
501 | def sabotage(me): |
502 | """Sabotage the peer, for testing purposes.""" | |
503 | me._sabotage = True | |
504 | if me._timer: me._timer.kill() | |
505 | T.defer(me._time) | |
506 | ||
b9dedfa6 MW |
507 | def info(me): |
508 | if not me._nping: | |
509 | mean = sd = '-' | |
510 | else: | |
511 | mean = me._sigma_t/me._nping | |
512 | sd = sqrt(me._sigma_t2/me._nping - mean*mean) | |
513 | n = me._nping + me._nlost | |
514 | if not n: pclost = '-' | |
515 | else: pclost = '%d' % ((100*me._nlost + n//2)//n) | |
516 | return { 'last-ping': me._last, | |
517 | 'mean-ping': '%.1fms' % mean, | |
518 | 'sd-ping': '%.1fms' % sd, | |
519 | 'n-ping': '%d' % me._nping, | |
520 | 'n-lost': '%d' % me._nlost, | |
521 | 'percent-lost': pclost, | |
522 | 'min-ping': '%.1fms' % me._min, | |
523 | 'max-ping': '%.1fms' % me._max, | |
524 | 'state': me._timer and 'idle' or 'check', | |
525 | 'failures': me._failures } | |
526 | ||
d64ce4ae MW |
527 | @T._callback |
528 | def _time(me): | |
529 | """ | |
530 | Handle timer callbacks by posting a timeout event on the queue. | |
531 | """ | |
532 | me._timer = None | |
533 | me._q.put(((me._peer, me.seq), 'TIMER', None)) | |
534 | ||
535 | def __str__(me): | |
536 | return 'PingPeer(%s, %d, f = %d)' % (me._peer, me.seq, me._failures) | |
537 | def __repr__(me): | |
538 | return str(me) | |
539 | ||
540 | class Pinger (T.Coroutine): | |
541 | """ | |
542 | The Pinger keeps track of the peers which we expect to be connected and | |
543 | takes action if they seem to stop responding. | |
544 | ||
545 | There is usually only one Pinger, called pinger. | |
546 | ||
547 | The Pinger maintains a collection of PingPeer objects, and an event queue. | |
548 | The PingPeers direct the results of their pings, and timer events, to the | |
549 | event queue. The Pinger's coroutine picks items off the queue and | |
550 | dispatches them back to the PingPeers as appropriate. | |
551 | """ | |
552 | ||
553 | def __init__(me): | |
554 | """Initialize the Pinger.""" | |
555 | T.Coroutine.__init__(me) | |
556 | me._peers = {} | |
557 | me._q = T.Queue() | |
558 | ||
559 | def run(me): | |
560 | """ | |
561 | Coroutine function: reads the pinger queue and sends events to the | |
562 | PingPeer objects they correspond to. | |
563 | """ | |
564 | while True: | |
565 | (peer, seq), code, stuff = me._q.get() | |
566 | if peer in me._peers and seq == me._peers[peer].seq: | |
567 | me._peers[peer].event(code, stuff) | |
568 | ||
569 | def add(me, peer, pingnow): | |
570 | """ | |
571 | Add PEER to the collection of peers under the Pinger's watchful eye. | |
572 | The arguments are as for PingPeer: see above. | |
573 | """ | |
574 | me._peers[peer.name] = PingPeer(me, me._q, peer, pingnow) | |
575 | return me | |
576 | ||
577 | def kill(me, peername): | |
578 | """Remove PEER from the peers being watched by the Pinger.""" | |
47912108 MW |
579 | try: del me._peers[peername] |
580 | except KeyError: pass | |
d64ce4ae MW |
581 | return me |
582 | ||
583 | def rescan(me, startup): | |
584 | """ | |
585 | General resynchronization method. | |
586 | ||
587 | We scan the list of peers (with connect scripts) known at the server. | |
588 | Any which are known to the Pinger but aren't known to the server are | |
589 | removed from our list; newly arrived peers are added. (Note that a peer | |
590 | can change state here either due to the server sneakily changing its list | |
591 | without issuing notifications or, more likely, the database changing its | |
592 | idea of whether a peer is interesting.) Finally, PingPeers which are | |
593 | still present are prodded to update their timing parameters. | |
594 | ||
595 | This method is called once at startup to pick up the peers already | |
596 | installed, and again by the dbwatcher coroutine when it detects a change | |
597 | to the database. | |
598 | """ | |
599 | if T._debug: print '# rescan peers' | |
600 | correct = {} | |
601 | start = {} | |
602 | for name in S.list(): | |
603 | try: peer = Peer(name) | |
604 | except KeyError: continue | |
605 | if peer.get('watch', filter = boolean, default = False): | |
606 | if T._debug: print '# interesting peer %s' % peer | |
607 | correct[peer.name] = start[peer.name] = peer | |
608 | elif startup: | |
609 | if T._debug: print '# peer %s ready for adoption' % peer | |
610 | start[peer.name] = peer | |
611 | for name, obj in me._peers.items(): | |
612 | try: | |
613 | peer = correct[name] | |
614 | except KeyError: | |
615 | if T._debug: print '# peer %s vanished' % name | |
616 | del me._peers[name] | |
617 | else: | |
618 | obj.update(peer) | |
619 | for name, peer in start.iteritems(): | |
620 | if name in me._peers: continue | |
621 | if startup: | |
622 | if T._debug: print '# setting up peer %s' % name | |
623 | ifname = S.ifname(name) | |
624 | addr = S.addr(name) | |
625 | T.defer(adoptpeer, peer, ifname, *addr) | |
626 | else: | |
627 | if T._debug: print '# adopting new peer %s' % name | |
628 | me.add(peer, True) | |
629 | return me | |
630 | ||
631 | def adopted(me): | |
632 | """ | |
633 | Returns the list of peers being watched by the Pinger. | |
634 | """ | |
635 | return me._peers.keys() | |
636 | ||
fb52c291 MW |
637 | def find(me, name): |
638 | """Return the PingPeer with the given name.""" | |
639 | return me._peers[name] | |
640 | ||
d64ce4ae MW |
641 | ###-------------------------------------------------------------------------- |
642 | ### New connections. | |
643 | ||
644 | def encode_envvars(env, prefix, vars): | |
645 | """ | |
646 | Encode the variables in VARS suitably for including in a program | |
647 | environment. Lowercase letters in variable names are forced to uppercase; | |
648 | runs of non-alphanumeric characters are replaced by single underscores; and | |
649 | the PREFIX is prepended. The resulting variables are written to ENV. | |
650 | """ | |
651 | for k, v in vars.iteritems(): | |
652 | env[prefix + r_bad.sub('_', k.upper())] = v | |
653 | ||
654 | r_bad = RX.compile(r'[\W_]+') | |
655 | def envvars(peer): | |
656 | """ | |
657 | Translate the database information for a PEER into a dictionary of | |
658 | environment variables with plausible upper-case names and a P_ prefix. | |
659 | Also collect the crypto information into A_ variables. | |
660 | """ | |
661 | env = {} | |
662 | encode_envvars(env, 'P_', dict([(k, peer.get(k)) for k in peer.list()])) | |
663 | encode_envvars(env, 'A_', S.algs(peer.name)) | |
664 | return env | |
665 | ||
666 | def run_ifupdown(what, peer, *args): | |
667 | """ | |
668 | Run the interface up/down script for a peer. | |
669 | ||
670 | WHAT is 'ifup' or 'ifdown'. PEER names the peer in question. ARGS is a | |
671 | list of arguments to pass to the script, in addition to the peer name. | |
672 | ||
673 | The command is run and watched in the background by potwatch. | |
674 | """ | |
675 | q = T.Queue() | |
676 | c = Command([what, peer.name], q, what, | |
677 | M.split(peer.get(what), quotep = True)[0] + | |
678 | [peer.name] + list(args), | |
679 | envvars(peer)) | |
680 | potwatch(what, peer.name, q) | |
681 | ||
682 | def adoptpeer(peer, ifname, *addr): | |
683 | """ | |
684 | Add a new peer to our collection. | |
685 | ||
686 | PEER is the `Peer' object; IFNAME is the interface name for its tunnel; and | |
687 | ADDR is the list of tokens representing its address. | |
688 | ||
689 | We try to bring up the interface and provoke a connection to the peer if | |
690 | it's passive. | |
691 | """ | |
692 | if peer.has('ifup'): | |
693 | T.Coroutine(run_ifupdown, name = 'ifup %s' % peer.name) \ | |
694 | .switch('ifup', peer, ifname, *addr) | |
695 | cmd = peer.get('connect', default = None) | |
696 | if cmd is not None: | |
697 | T.Coroutine(run_connect, name = 'connect %s' % peer.name) \ | |
698 | .switch(peer, cmd) | |
699 | if peer.get('watch', filter = boolean, default = False): | |
700 | pinger.add(peer, False) | |
701 | ||
702 | def disownpeer(peer): | |
703 | """Drop the PEER from the Pinger and put its interface to bed.""" | |
704 | try: pinger.kill(peer) | |
705 | except KeyError: pass | |
706 | cmd = peer.get('disconnect', default = None) | |
707 | if cmd is not None: | |
708 | T.Coroutine(run_disconnect, name = 'disconnect %s' % peer.name) \ | |
709 | .switch(peer, cmd) | |
710 | if peer.has('ifdown'): | |
711 | T.Coroutine(run_ifupdown, name = 'ifdown %s' % peer.name) \ | |
712 | .switch('ifdown', peer) | |
713 | ||
a62f8e8a MW |
714 | def addpeer(peer, addr): |
715 | """ | |
716 | Process a connect request from a new peer PEER on address ADDR. | |
717 | ||
718 | Any existing peer with this name is disconnected from the server. | |
719 | """ | |
720 | if peer.name in S.list(): | |
721 | S.kill(peer.name) | |
722 | try: | |
6411163d | 723 | booltrue = ['t', 'true', 'y', 'yes', 'on'] |
a62f8e8a MW |
724 | S.add(peer.name, |
725 | tunnel = peer.get('tunnel', None), | |
726 | keepalive = peer.get('keepalive', None), | |
48b84569 | 727 | key = peer.get('key', None), |
fe2a5dcf | 728 | priv = peer.get('priv', None), |
6411163d MW |
729 | mobile = peer.get('mobile', 'nil') in booltrue, |
730 | cork = peer.get('cork', 'nil') in booltrue, | |
a62f8e8a MW |
731 | *addr) |
732 | except T.TripeError, exc: | |
733 | raise T.TripeJobError(*exc.args) | |
734 | ||
d64ce4ae MW |
735 | ## Dictionary mapping challenges to waiting passive-connection coroutines. |
736 | chalmap = {} | |
737 | ||
738 | def notify(_, code, *rest): | |
739 | """ | |
740 | Watch for notifications. | |
741 | ||
742 | We trap ADD and KILL notifications, and send them straight to adoptpeer and | |
743 | disownpeer respectively; and dispatch GREET notifications to the | |
744 | corresponding waiting coroutine. | |
745 | """ | |
746 | if code == 'ADD': | |
747 | try: p = Peer(rest[0]) | |
748 | except KeyError: return | |
749 | adoptpeer(p, *rest[1:]) | |
750 | elif code == 'KILL': | |
751 | try: p = Peer(rest[0]) | |
752 | except KeyError: return | |
753 | disownpeer(p, *rest[1:]) | |
754 | elif code == 'GREET': | |
755 | chal = rest[0] | |
756 | try: cr = chalmap[chal] | |
757 | except KeyError: pass | |
758 | else: cr.switch(rest[1:]) | |
759 | ||
760 | ###-------------------------------------------------------------------------- | |
761 | ### Command implementation. | |
762 | ||
763 | def cmd_kick(name): | |
764 | """ | |
765 | kick NAME: Force a new connection attempt for the NAMEd peer. | |
766 | """ | |
fb52c291 MW |
767 | try: pp = pinger.find(name) |
768 | except KeyError: raise T.TripeJobError('peer-not-adopted', name) | |
d64ce4ae MW |
769 | try: peer = Peer(name) |
770 | except KeyError: raise T.TripeJobError('unknown-peer', name) | |
8bd108e4 MW |
771 | conn = peer.get('connect', None) |
772 | if conn: T.spawn(run_connect, peer, peer.get('connect')) | |
773 | else: T.spawn(lambda p: S.forcekx(p.name), peer) | |
d64ce4ae MW |
774 | |
775 | def cmd_adopted(): | |
776 | """ | |
777 | adopted: Report a list of adopted peers. | |
778 | """ | |
779 | for name in pinger.adopted(): | |
780 | T.svcinfo(name) | |
781 | ||
a62f8e8a MW |
782 | def cmd_active(name): |
783 | """ | |
784 | active NAME: Handle an active connection request for the peer called NAME. | |
785 | ||
786 | The appropriate address is read from the database automatically. | |
787 | """ | |
d64ce4ae MW |
788 | try: peer = Peer(name) |
789 | except KeyError: raise T.TripeJobError('unknown-peer', name) | |
a62f8e8a MW |
790 | addr = peer.get('peer') |
791 | if addr == 'PASSIVE': | |
792 | raise T.TripeJobError('passive-peer', name) | |
793 | addpeer(peer, M.split(addr, quotep = True)[0]) | |
794 | ||
d64ce4ae | 795 | def cmd_listactive(): |
a62f8e8a MW |
796 | """ |
797 | list: Report a list of the available active peers. | |
798 | """ | |
799 | cdb = CDB.init(opts.cdb) | |
800 | for key in cdb.keys(): | |
801 | if key.startswith('P') and Peer(key[1:]).get('peer', '') != 'PASSIVE': | |
802 | T.svcinfo(key[1:]) | |
803 | ||
804 | def cmd_info(name): | |
805 | """ | |
806 | info NAME: Report the database entries for the named peer. | |
807 | """ | |
d64ce4ae MW |
808 | try: peer = Peer(name) |
809 | except KeyError: raise T.TripeJobError('unknown-peer', name) | |
b9dedfa6 MW |
810 | d = {} |
811 | try: pp = pinger.find(name) | |
812 | except KeyError: pass | |
813 | else: d.update(pp.info()) | |
814 | items = list(peer.list()) + d.keys() | |
a62f8e8a MW |
815 | items.sort() |
816 | for i in items: | |
b9dedfa6 MW |
817 | try: v = d[i] |
818 | except KeyError: v = peer.get(i) | |
819 | T.svcinfo('%s=%s' % (i, v)) | |
a62f8e8a | 820 | |
d3731285 MW |
821 | def cmd_userpeer(user): |
822 | """ | |
823 | userpeer USER: Report the peer name for the named user. | |
824 | """ | |
d64ce4ae MW |
825 | try: name = CDB.init(opts.cdb)['U' + user] |
826 | except KeyError: raise T.TripeJobError('unknown-user', user) | |
827 | T.svcinfo(name) | |
a62f8e8a MW |
828 | |
829 | def cmd_passive(*args): | |
830 | """ | |
831 | passive [OPTIONS] USER: Await the arrival of the named USER. | |
832 | ||
833 | Report a challenge; when (and if!) the server receives a greeting quoting | |
834 | this challenge, add the corresponding peer to the server. | |
835 | """ | |
836 | timeout = 30 | |
837 | op = T.OptParse(args, ['-timeout']) | |
838 | for opt in op: | |
839 | if opt == '-timeout': | |
840 | timeout = T.timespec(op.arg()) | |
841 | user, = op.rest(1, 1) | |
d64ce4ae MW |
842 | try: name = CDB.init(opts.cdb)['U' + user] |
843 | except KeyError: raise T.TripeJobError('unknown-user', user) | |
844 | try: peer = Peer(name) | |
845 | except KeyError: raise T.TripeJobError('unknown-peer', name) | |
a62f8e8a MW |
846 | chal = S.getchal() |
847 | cr = T.Coroutine.getcurrent() | |
848 | timer = M.SelTimer(time() + timeout, lambda: cr.switch(None)) | |
849 | try: | |
850 | T.svcinfo(chal) | |
851 | chalmap[chal] = cr | |
852 | addr = cr.parent.switch() | |
853 | if addr is None: | |
854 | raise T.TripeJobError('connect-timeout') | |
d64ce4ae | 855 | addpeer(peer, addr) |
a62f8e8a MW |
856 | finally: |
857 | del chalmap[chal] | |
858 | ||
965eb987 MW |
859 | def cmd_sabotage(name): |
860 | """ | |
861 | sabotage NAME: Sabotage the NAMEd peer so that we think it can't be pinged. | |
862 | """ | |
863 | try: pp = pinger.find(name) | |
864 | except KeyError: raise T.TripeJobError('unknown-peer', name) | |
865 | pp.sabotage() | |
866 | ||
a62f8e8a MW |
867 | ###-------------------------------------------------------------------------- |
868 | ### Start up. | |
869 | ||
870 | def setup(): | |
871 | """ | |
872 | Service setup. | |
873 | ||
d64ce4ae MW |
874 | Register the notification watcher, rescan the peers, and add automatic |
875 | active peers. | |
a62f8e8a MW |
876 | """ |
877 | S.handler['NOTE'] = notify | |
878 | S.watch('+n') | |
d64ce4ae MW |
879 | |
880 | pinger.rescan(opts.startup) | |
881 | ||
a62f8e8a MW |
882 | if opts.startup: |
883 | cdb = CDB.init(opts.cdb) | |
884 | try: | |
885 | autos = cdb['%AUTO'] | |
886 | except KeyError: | |
887 | autos = '' | |
888 | for name in M.split(autos)[0]: | |
889 | try: | |
890 | peer = Peer(name, cdb) | |
891 | addpeer(peer, M.split(peer.get('peer'), quotep = True)[0]) | |
892 | except T.TripeJobError, err: | |
893 | S.warn('connect', 'auto-add-failed', name, *err.args) | |
894 | ||
d64ce4ae MW |
895 | def init(): |
896 | """ | |
897 | Initialization to be done before service startup. | |
898 | """ | |
899 | global errorwatch, childwatch, pinger | |
900 | errorwatch = ErrorWatch() | |
901 | childwatch = ChildWatch() | |
902 | pinger = Pinger() | |
903 | T.Coroutine(dbwatch, name = 'dbwatch').switch() | |
904 | errorwatch.switch() | |
905 | pinger.switch() | |
906 | ||
a62f8e8a MW |
907 | def parse_options(): |
908 | """ | |
909 | Parse the command-line options. | |
910 | ||
911 | Automatically changes directory to the requested configdir, and turns on | |
912 | debugging. Returns the options object. | |
913 | """ | |
914 | op = OptionParser(usage = '%prog [-a FILE] [-d DIR]', | |
915 | version = '%%prog %s' % VERSION) | |
916 | ||
917 | op.add_option('-a', '--admin-socket', | |
918 | metavar = 'FILE', dest = 'tripesock', default = T.tripesock, | |
919 | help = 'Select socket to connect to [default %default]') | |
920 | op.add_option('-d', '--directory', | |
921 | metavar = 'DIR', dest = 'dir', default = T.configdir, | |
922 | help = 'Select current diretory [default %default]') | |
923 | op.add_option('-p', '--peerdb', | |
924 | metavar = 'FILE', dest = 'cdb', default = T.peerdb, | |
925 | help = 'Select peers database [default %default]') | |
926 | op.add_option('--daemon', dest = 'daemon', | |
927 | default = False, action = 'store_true', | |
928 | help = 'Become a daemon after successful initialization') | |
929 | op.add_option('--debug', dest = 'debug', | |
930 | default = False, action = 'store_true', | |
931 | help = 'Emit debugging trace information') | |
932 | op.add_option('--startup', dest = 'startup', | |
933 | default = False, action = 'store_true', | |
934 | help = 'Being called as part of the server startup') | |
935 | ||
936 | opts, args = op.parse_args() | |
937 | if args: op.error('no arguments permitted') | |
938 | OS.chdir(opts.dir) | |
939 | T._debug = opts.debug | |
940 | return opts | |
941 | ||
942 | ## Service table, for running manually. | |
d64ce4ae MW |
943 | service_info = [('connect', T.VERSION, { |
944 | 'adopted': (0, 0, '', cmd_adopted), | |
945 | 'kick': (1, 1, 'PEER', cmd_kick), | |
a62f8e8a MW |
946 | 'passive': (1, None, '[OPTIONS] USER', cmd_passive), |
947 | 'active': (1, 1, 'PEER', cmd_active), | |
948 | 'info': (1, 1, 'PEER', cmd_info), | |
d64ce4ae | 949 | 'list-active': (0, 0, '', cmd_listactive), |
965eb987 MW |
950 | 'userpeer': (1, 1, 'USER', cmd_userpeer), |
951 | 'sabotage': (1, 1, 'PEER', cmd_sabotage) | |
a62f8e8a MW |
952 | })] |
953 | ||
954 | if __name__ == '__main__': | |
955 | opts = parse_options() | |
956 | T.runservices(opts.tripesock, service_info, | |
d64ce4ae | 957 | init = init, setup = setup, |
a62f8e8a MW |
958 | daemon = opts.daemon) |
959 | ||
960 | ###----- That's all, folks -------------------------------------------------- |