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Mon Dec 10 17:34:22 2018 UTC (5 years, 4 months ago) by
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- Verification of CN when creating SSL tunnel on multi-domain servers.
CN is default lonid, i.e., one listed last for the node's hostname in
hosts.tab and/or dns_hosts.tab.
1: #!/usr/bin/perl
2: # The LearningOnline Network with CAPA
3: # lonc maintains the connections to remote computers
4: #
5: # $Id: loncnew,v 1.107 2018/12/10 17:34:22 raeburn Exp $
6: #
7: # Copyright Michigan State University Board of Trustees
8: #
9: # This file is part of the LearningOnline Network with CAPA (LON-CAPA).
10: ## LON-CAPA is free software; you can redistribute it and/or modify
11: # it under the terms of the GNU General Public License as published by
12: # the Free Software Foundation; either version 2 of the License, or
13: # (at your option) any later version.
14: #
15: # LON-CAPA is distributed in the hope that it will be useful,
16: # but WITHOUT ANY WARRANTY; without even the implied warranty of
17: # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18: # GNU General Public License for more details.
19: #
20: # You should have received a copy of the GNU General Public License
21: # along with LON-CAPA; if not, write to the Free Software
22: # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23: #
24: # /home/httpd/html/adm/gpl.txt
25: #
26: # http://www.lon-capa.org/
27: #
28: #
29: # new lonc handles n request out over m connections to londs.
30: # This module is based on the Event class.
31: # Development iterations:
32: # - Setup basic event loop. (done)
33: # - Add timer dispatch. (done)
34: # - Add ability to accept lonc UNIX domain sockets. (done)
35: # - Add ability to create/negotiate lond connections (done).
36: # - Add general logic for dispatching requests and timeouts. (done).
37: # - Add support for the lonc/lond requests. (done).
38: # - Add logging/status monitoring. (done)
39: # - Add Signal handling - HUP restarts. USR1 status report. (done)
40: # - Add Configuration file I/O (done).
41: # - Add management/status request interface. (done)
42: # - Add deferred request capability. (done)
43: # - Detect transmission timeouts. (done)
44: #
45:
46: use strict;
47: use lib "/home/httpd/lib/perl/";
48: use Event qw(:DEFAULT );
49: use POSIX qw(:signal_h);
50: use POSIX;
51: use IO::Socket;
52: use IO::Socket::INET;
53: use IO::Socket::UNIX;
54: use IO::File;
55: use IO::Handle;
56: use Socket;
57: use Crypt::IDEA;
58: use LONCAPA::Queue;
59: use LONCAPA::Stack;
60: use LONCAPA::LondConnection;
61: use LONCAPA::LondTransaction;
62: use LONCAPA::Configuration;
63: use Fcntl qw(:flock);
64:
65:
66: # Read the httpd configuration file to get perl variables
67: # normally set in apache modules:
68:
69: my $perlvarref = LONCAPA::Configuration::read_conf('loncapa.conf');
70: my %perlvar = %{$perlvarref};
71:
72: #
73: # parent and shared variables.
74:
75: my %ChildPid; # by pid -> host.
76: my %ChildHost; # by host.
77: my %ChildKeyMode; # by pid -> keymode
78: my %listening_to; # Socket->host table for who the parent
79: # is listening to.
80: my %parent_dispatchers; # host-> listener watcher events.
81:
82: my %parent_handlers; # Parent signal handlers...
83:
84: my $MaxConnectionCount = 10; # Will get from config later.
85: my $ClientConnection = 0; # Uniquifier for client events.
86:
87: my $DebugLevel = 0;
88: my $NextDebugLevel= 2; # So Sigint can toggle this.
89: my $IdleTimeout= 5*60; # Seconds to wait prior to pruning connections.
90:
91: my $LogTransactions = 0; # When True, all transactions/replies get logged.
92: my $executable = $0; # Get the full path to me.
93:
94: #
95: # The variables below are only used by the child processes.
96: #
97: my $RemoteHost; # Hostname of host child is talking to.
98: my $RemoteHostId; # lonid of host child is talking to.
99: my $RemoteDefHostId; # default lonhostID of host child is talking to.
100: my @all_host_ids;
101: my $UnixSocketDir= $perlvar{'lonSockDir'};
102: my $IdleConnections = Stack->new(); # Set of idle connections
103: my %ActiveConnections; # Connections to the remote lond.
104: my %ActiveTransactions; # LondTransactions in flight.
105: my %ActiveClients; # Serial numbers of active clients by socket.
106: my $WorkQueue = Queue->new(); # Queue of pending transactions.
107: my $ConnectionCount = 0;
108: my $IdleSeconds = 0; # Number of seconds idle.
109: my $Status = ""; # Current status string.
110: my $RecentLogEntry = "";
111: my $ConnectionRetries=5; # Number of connection retries allowed.
112: my $ConnectionRetriesLeft=5; # Number of connection retries remaining.
113: my $LondVersion = "unknown"; # Version of lond we talk with.
114: my $KeyMode = ""; # e.g. ssl, local, insecure from last connect.
115: my $LondConnecting = 0; # True when a connection is being built.
116:
117:
118:
119: my $I_am_child = 0; # True if this is the child process.
120:
121: #
122: # The hash below gives the HTML format for log messages
123: # given a severity.
124: #
125: my %LogFormats;
126:
127: $LogFormats{"CRITICAL"} = "<font color='red'>CRITICAL: %s</font>";
128: $LogFormats{"SUCCESS"} = "<font color='green'>SUCCESS: %s</font>";
129: $LogFormats{"INFO"} = "<font color='yellow'>INFO: %s</font>";
130: $LogFormats{"WARNING"} = "<font color='blue'>WARNING: %s</font>";
131: $LogFormats{"DEFAULT"} = " %s ";
132:
133:
134: # UpdateStatus;
135: # Update the idle status display to show how many connections
136: # are left, retries and other stuff.
137: #
138: sub UpdateStatus {
139: if ($ConnectionRetriesLeft > 0) {
140: ShowStatus(GetServerHost()." Connection count: ".$ConnectionCount
141: ." Retries remaining: ".$ConnectionRetriesLeft
142: ." ($KeyMode)");
143: } else {
144: ShowStatus(GetServerHost()." >> DEAD <<");
145: }
146: }
147:
148:
149: =pod
150:
151: =head2 LogPerm
152:
153: Makes an entry into the permanent log file.
154:
155: =cut
156:
157: sub LogPerm {
158: my $message=shift;
159: my $execdir=$perlvar{'lonDaemons'};
160: my $now=time;
161: my $local=localtime($now);
162: my $fh=IO::File->new(">>$execdir/logs/lonnet.perm.log");
163: chomp($message);
164: print $fh "$now:$message:$local\n";
165: }
166:
167: =pod
168:
169: =head2 Log
170:
171: Logs a message to the log file.
172: Parameters:
173:
174: =item severity
175:
176: One of CRITICAL, WARNING, INFO, SUCCESS used to select the
177: format string used to format the message. if the severity is
178: not a defined severity the Default format string is used.
179:
180: =item message
181:
182: The base message. In addtion to the format string, the message
183: will be appended to a string containing the name of our remote
184: host and the time will be formatted into the message.
185:
186: =cut
187:
188: sub Log {
189:
190: my ($severity, $message) = @_;
191:
192: if(!$LogFormats{$severity}) {
193: $severity = "DEFAULT";
194: }
195:
196: my $format = $LogFormats{$severity};
197:
198: # Put the window dressing in in front of the message format:
199:
200: my $now = time;
201: my $local = localtime($now);
202: my $finalformat = "$local ($$) [$RemoteHost] [$Status] ";
203: $finalformat = $finalformat.$format."\n";
204:
205: # open the file and put the result.
206:
207: my $execdir = $perlvar{'lonDaemons'};
208: my $fh = IO::File->new(">>$execdir/logs/lonc.log");
209: my $msg = sprintf($finalformat, $message);
210: $RecentLogEntry = $msg;
211: print $fh $msg;
212:
213:
214: }
215:
216:
217: =pod
218:
219: =head2 GetPeerName
220:
221: Returns the name of the host that a socket object is connected to.
222:
223: =cut
224:
225: sub GetPeername {
226:
227:
228: my ($connection, $AdrFamily) = @_;
229:
230: my $peer = $connection->peername();
231: my $peerport;
232: my $peerip;
233: if($AdrFamily == AF_INET) {
234: ($peerport, $peerip) = sockaddr_in($peer);
235: my $peername = gethostbyaddr($peerip, $AdrFamily);
236: return $peername;
237: } elsif ($AdrFamily == AF_UNIX) {
238: my $peerfile;
239: ($peerfile) = sockaddr_un($peer);
240: return $peerfile;
241: }
242: }
243: =pod
244:
245: =head2 Debug
246:
247: Invoked to issue a debug message.
248:
249: =cut
250:
251: sub Debug {
252:
253: my ($level, $message) = @_;
254:
255: if ($level <= $DebugLevel) {
256: Log("INFO", "-Debug- $message host = $RemoteHost");
257: }
258: }
259:
260: sub SocketDump {
261:
262: my ($level, $socket) = @_;
263:
264: if($level <= $DebugLevel) {
265: $socket->Dump(-1); # Ensure it will get dumped.
266: }
267: }
268:
269: =pod
270:
271: =head2 ShowStatus
272:
273: Place some text as our pid status.
274: and as what we return in a SIGUSR1
275:
276: =cut
277:
278: sub ShowStatus {
279: my $state = shift;
280: my $now = time;
281: my $local = localtime($now);
282: $Status = $local.": ".$state;
283: $0='lonc: '.$state.' '.$local;
284: }
285:
286: =pod
287:
288: =head2 SocketTimeout
289:
290: Called when an action on the socket times out. The socket is
291: destroyed and any active transaction is failed.
292:
293:
294: =cut
295:
296: sub SocketTimeout {
297: my $Socket = shift;
298: Log("WARNING", "A socket timeout was detected");
299: Debug(5, " SocketTimeout called: ");
300: $Socket->Dump(0);
301: if(exists($ActiveTransactions{$Socket})) {
302: FailTransaction($ActiveTransactions{$Socket});
303: }
304: KillSocket($Socket); # A transaction timeout also counts as
305: # a connection failure:
306: $ConnectionRetriesLeft--;
307: if($ConnectionRetriesLeft <= 0) {
308: Log("CRITICAL", "Host marked DEAD: ".GetServerHost());
309: $LondConnecting = 0;
310: }
311:
312: }
313:
314: #
315: # This function should be called by the child in all cases where it must
316: # exit. The child process must create a lock file for the AF_UNIX socket
317: # in order to prevent connection requests from lonnet in the time between
318: # process exit and the parent picking up the listen again.
319: #
320: # Parameters:
321: # exit_code - Exit status value, however see the next parameter.
322: # message - If this optional parameter is supplied, the exit
323: # is via a die with this message.
324: #
325: sub child_exit {
326: my ($exit_code, $message) = @_;
327:
328: # Regardless of how we exit, we may need to do the lock thing:
329:
330: #
331: # Create a lock file since there will be a time window
332: # between our exit and the parent's picking up the listen
333: # during which no listens will be done on the
334: # lonnet client socket.
335: #
336: my $lock_file = &GetLoncSocketPath().".lock";
337: open(LOCK,">$lock_file");
338: print LOCK "Contents not important";
339: close(LOCK);
340: unlink(&GetLoncSocketPath());
341:
342: if ($message) {
343: die($message);
344: } else {
345: exit($exit_code);
346: }
347: }
348: #----------------------------- Timer management ------------------------
349:
350: =pod
351:
352: =head2 Tick
353:
354: Invoked each timer tick.
355:
356: =cut
357:
358:
359: sub Tick {
360: my ($Event) = @_;
361: my $clock_watcher = $Event->w;
362:
363: my $client;
364: UpdateStatus();
365:
366: # Is it time to prune connection count:
367:
368:
369: if($IdleConnections->Count() &&
370: ($WorkQueue->Count() == 0)) { # Idle connections and nothing to do?
371: $IdleSeconds++;
372: if($IdleSeconds > $IdleTimeout) { # Prune a connection...
373: my $Socket = $IdleConnections->pop();
374: KillSocket($Socket);
375: $IdleSeconds = 0; # Otherwise all connections get trimmed to fast.
376: UpdateStatus();
377: if(($ConnectionCount == 0)) {
378: &child_exit(0);
379:
380: }
381: }
382: } else {
383: $IdleSeconds = 0; # Reset idle count if not idle.
384: }
385: #
386: # For each inflight transaction, tick down its timeout counter.
387: #
388:
389: foreach my $item (keys %ActiveConnections) {
390: my $State = $ActiveConnections{$item}->data->GetState();
391: if ($State ne 'Idle') {
392: Debug(5,"Ticking Socket $State $item");
393: $ActiveConnections{$item}->data->Tick();
394: }
395: }
396: # Do we have work in the queue, but no connections to service them?
397: # If so, try to make some new connections to get things going again.
398: #
399: # Note this code is dead now...
400: #
401: my $Requests = $WorkQueue->Count();
402: if (($ConnectionCount == 0) && ($Requests > 0) && (!$LondConnecting)) {
403: if ($ConnectionRetriesLeft > 0) {
404: Debug(5,"Work but no connections, Make a new one");
405: my $success;
406: $success = &MakeLondConnection;
407: if($success == 0) { # All connections failed:
408: Debug(5,"Work in queue failed to make any connectiouns\n");
409: EmptyQueue(); # Fail pending transactions with con_lost.
410: CloseAllLondConnections(); # Should all be closed but....
411: }
412: } else {
413: $LondConnecting = 0;
414: ShowStatus(GetServerHost()." >>> DEAD!!! <<<");
415: Debug(5,"Work in queue, but gave up on connections..flushing\n");
416: EmptyQueue(); # Connections can't be established.
417: CloseAllLondConnections(); # Should all already be closed but...
418: }
419:
420: }
421: if ($ConnectionCount == 0) {
422: $KeyMode = "";
423: $clock_watcher->cancel();
424: }
425: &UpdateStatus();
426: }
427:
428: =pod
429:
430: =head2 SetupTimer
431:
432: Sets up a 1 per sec recurring timer event. The event handler is used to:
433:
434: =item
435:
436: Trigger timeouts on communications along active sockets.
437:
438: =item
439:
440: Trigger disconnections of idle sockets.
441:
442: =cut
443:
444: sub SetupTimer {
445: Debug(6, "SetupTimer");
446: Event->timer(interval => 1, cb => \&Tick,
447: hard => 1);
448: }
449:
450: =pod
451:
452: =head2 ServerToIdle
453:
454: This function is called when a connection to the server is
455: ready for more work.
456:
457: If there is work in the Work queue the top element is dequeued
458: and the connection will start to work on it. If the work queue is
459: empty, the connection is pushed on the idle connection stack where
460: it will either get another work unit, or alternatively, if it sits there
461: long enough, it will be shut down and released.
462:
463: =cut
464:
465: sub ServerToIdle {
466: my $Socket = shift; # Get the socket.
467: $KeyMode = $Socket->{AuthenticationMode};
468: delete($ActiveTransactions{$Socket}); # Server has no transaction
469:
470: &Debug(5, "Server to idle");
471:
472: # If there's work to do, start the transaction:
473:
474: my $reqdata = $WorkQueue->dequeue(); # This is a LondTransaction
475: if ($reqdata ne undef) {
476: Debug(5, "Queue gave request data: ".$reqdata->getRequest());
477: &StartRequest($Socket, $reqdata);
478:
479: } else {
480:
481: # There's no work waiting, so push the server to idle list.
482: &Debug(5, "No new work requests, server connection going idle");
483: $IdleConnections->push($Socket);
484: }
485: }
486:
487: =pod
488:
489: =head2 ClientWritable
490:
491: Event callback for when a client socket is writable.
492:
493: This callback is established when a transaction response is
494: available from lond. The response is forwarded to the unix socket
495: as it becomes writable in this sub.
496:
497: Parameters:
498:
499: =item Event
500:
501: The event that has been triggered. Event->w->data is
502: the data and Event->w->fd is the socket to write.
503:
504: =cut
505:
506: sub ClientWritable {
507: my $Event = shift;
508: my $Watcher = $Event->w;
509: if (!defined($Watcher)) {
510: &child_exit(-1,'No watcher for event in ClientWritable');
511: }
512: my $Data = $Watcher->data;
513: my $Socket = $Watcher->fd;
514:
515: # Try to send the data:
516:
517: &Debug(6, "ClientWritable writing".$Data);
518: &Debug(9, "Socket is: ".$Socket);
519:
520: if($Socket->connected) {
521: my $result = $Socket->send($Data, 0);
522:
523: # $result undefined: the write failed.
524: # otherwise $result is the number of bytes written.
525: # Remove that preceding string from the data.
526: # If the resulting data is empty, destroy the watcher
527: # and set up a read event handler to accept the next
528: # request.
529:
530: &Debug(9,"Send result is ".$result." Defined: ".defined($result));
531: if($result ne undef) {
532: &Debug(9, "send result was defined");
533: if($result == length($Data)) { # Entire string sent.
534: &Debug(9, "ClientWritable data all written");
535: $Watcher->cancel();
536: #
537: # Set up to read next request from socket:
538:
539: my $descr = sprintf("Connection to lonc client %d",
540: $ActiveClients{$Socket});
541: Event->io(cb => \&ClientRequest,
542: poll => 'r',
543: desc => $descr,
544: data => "",
545: fd => $Socket);
546:
547: } else { # Partial string sent.
548: $Watcher->data(substr($Data, $result));
549: if($result == 0) { # client hung up on us!!
550: # Log("INFO", "lonc pipe client hung up on us!");
551: $Watcher->cancel;
552: $Socket->shutdown(2);
553: $Socket->close();
554: }
555: }
556:
557: } else { # Error of some sort...
558:
559: # Some errnos are possible:
560: my $errno = $!;
561: if($errno == POSIX::EWOULDBLOCK ||
562: $errno == POSIX::EAGAIN ||
563: $errno == POSIX::EINTR) {
564: # No action taken...the socket will be writable firing the event again
565: # which will result in a retry of the write.
566: } else { # Unanticipated errno.
567: &Debug(5,"ClientWritable error or peer shutdown".$RemoteHost);
568: $Watcher->cancel; # Stop the watcher.
569: $Socket->shutdown(2); # Kill connection
570: $Socket->close(); # Close the socket.
571: }
572:
573: }
574: } else {
575: $Watcher->cancel(); # A delayed request...just cancel.
576: return;
577: }
578: }
579:
580: =pod
581:
582: =head2 CompleteTransaction
583:
584: Called when the reply data has been received for a lond
585: transaction. The reply data must now be sent to the
586: ultimate client on the other end of the Unix socket. This is
587: done by setting up a writable event for the socket with the
588: data the reply data.
589:
590: Parameters:
591:
592: =item Socket
593:
594: Socket on which the lond transaction occurred. This is a
595: LondConnection. The data received are in the TransactionReply member.
596:
597: =item Transaction
598:
599: The transaction that is being completed.
600:
601: =cut
602:
603: sub CompleteTransaction {
604: &Debug(5,"Complete transaction");
605:
606: my ($Socket, $Transaction) = @_;
607:
608: if (!$Transaction->isDeferred()) { # Normal transaction
609: my $data = $Socket->GetReply(); # Data to send.
610: if($LogTransactions) {
611: Log("SUCCESS", "Reply from lond: '$data'");
612: }
613: StartClientReply($Transaction, $data);
614: } else { # Delete deferred transaction file.
615: Log("SUCCESS", "A delayed transaction was completed");
616: LogPerm("S:".$Socket->PeerLoncapaHim().":".$Transaction->getRequest());
617: unlink($Transaction->getFile());
618: }
619: }
620:
621: =pod
622:
623: =head1 StartClientReply
624:
625: Initiates a reply to a client where the reply data is a parameter.
626:
627: =head2 parameters:
628:
629: =item Transaction
630:
631: The transaction for which we are responding to the client.
632:
633: =item data
634:
635: The data to send to apache client.
636:
637: =cut
638:
639: sub StartClientReply {
640:
641: my ($Transaction, $data) = @_;
642:
643: my $Client = $Transaction->getClient();
644:
645: &Debug(8," Reply was: ".$data);
646: my $Serial = $ActiveClients{$Client};
647: my $desc = sprintf("Connection to lonc client %d",
648: $Serial);
649: Event->io(fd => $Client,
650: poll => "w",
651: desc => $desc,
652: cb => \&ClientWritable,
653: data => $data);
654: }
655:
656: =pod
657:
658: =head2 FailTransaction
659:
660: Finishes a transaction with failure because the associated lond socket
661: disconnected. There are two possibilities:
662: - The transaction is deferred: in which case we just quietly
663: delete the transaction since there is no client connection.
664: - The transaction is 'live' in which case we initiate the sending
665: of "con_lost" to the client.
666:
667: Deleting the transaction means killing it from the %ActiveTransactions hash.
668:
669: Parameters:
670:
671: =item client
672:
673: The LondTransaction we are failing.
674:
675:
676: =cut
677:
678: sub FailTransaction {
679: my $transaction = shift;
680:
681: # If the socket is dead, that's already logged.
682:
683: if ($ConnectionRetriesLeft > 0) {
684: Log("WARNING", "Failing transaction "
685: .$transaction->getLoggableRequest());
686: }
687: Debug(1, "Failing transaction: ".$transaction->getLoggableRequest());
688: if (!$transaction->isDeferred()) { # If the transaction is deferred we'll get to it.
689: my $client = $transaction->getClient();
690: Debug(1," Replying con_lost to ".$transaction->getRequest());
691: StartClientReply($transaction, "con_lost\n");
692: }
693:
694: }
695:
696: =pod
697:
698: =head1 EmptyQueue
699:
700: Fails all items in the work queue with con_lost.
701: Note that each item in the work queue is a transaction.
702:
703: =cut
704:
705: sub EmptyQueue {
706: $ConnectionRetriesLeft--; # Counts as connection failure too.
707: while($WorkQueue->Count()) {
708: my $request = $WorkQueue->dequeue(); # This is a transaction
709: FailTransaction($request);
710: }
711: }
712:
713: =pod
714:
715: =head2 CloseAllLondConnections
716:
717: Close all connections open on lond prior to exit e.g.
718:
719: =cut
720:
721: sub CloseAllLondConnections {
722: foreach my $Socket (keys %ActiveConnections) {
723: if(exists($ActiveTransactions{$Socket})) {
724: FailTransaction($ActiveTransactions{$Socket});
725: }
726: KillSocket($Socket);
727: }
728: }
729:
730: =pod
731:
732: =head2 KillSocket
733:
734: Destroys a socket. This function can be called either when a socket
735: has died of 'natural' causes or because a socket needs to be pruned due to
736: idleness. If the socket has died naturally, if there are no longer any
737: live connections a new connection is created (in case there are transactions
738: in the queue). If the socket has been pruned, it is never re-created.
739:
740: Parameters:
741:
742: =item Socket
743:
744: The socket to kill off.
745:
746: =item restart
747:
748: non-zero if we are allowed to create a new connection.
749:
750: =cut
751:
752: sub KillSocket {
753: my $Socket = shift;
754: my $restart = shift;
755:
756: Log("WARNING", "Shutting down a socket");
757: $Socket->Shutdown();
758:
759: # If the socket came from the active connection set,
760: # delete its transaction... note that FailTransaction should
761: # already have been called!!!
762: # otherwise it came from the idle set.
763: #
764:
765: if(exists($ActiveTransactions{$Socket})) {
766: delete ($ActiveTransactions{$Socket});
767: }
768: if(exists($ActiveConnections{$Socket})) {
769: $ActiveConnections{$Socket}->cancel;
770: delete($ActiveConnections{$Socket});
771: # Decrement ConnectionCount unless we will immediately
772: # re-connect (i.e., $restart is true), because this was
773: # a connection where the SSL channel for exchange of the
774: # shared key failed, and we may use an insecure channel.
775: unless ($restart) {
776: $ConnectionCount--;
777: }
778: if ($ConnectionCount < 0) { $ConnectionCount = 0; }
779: }
780: # If the connection count has gone to zero and there is work in the
781: # work queue, the work all gets failed with con_lost.
782: #
783:
784: if($ConnectionCount == 0) {
785: $LondConnecting = 0; # No connections so also not connecting.
786: EmptyQueue();
787: CloseAllLondConnections(); # Should all already be closed but...
788: &clear_childpid($$);
789: }
790: UpdateStatus();
791: }
792:
793: =pod
794:
795: =head2 LondReadable
796:
797: This function is called whenever a lond connection
798: is readable. The action is state dependent:
799:
800: =head3 State=Initialized
801:
802: We are waiting for the challenge, this is a no-op until the
803: state changes.
804:
805: =head3 State=Challenged
806:
807: The challenge has arrived we need to transition to Writable.
808: The connection must echo the challenge back.
809:
810: =head3 State=ChallengeReplied
811:
812: The challenge has been replied to. Then we are receiving the
813: 'ok' from the partner.
814:
815: =head3 State=ReadingVersionString
816:
817: We have requested the lond version and are reading the
818: version back. Upon completion, we'll store the version away
819: for future use(?).
820:
821: =head3 State=HostSet
822:
823: We have selected the domain name of our peer (multhomed hosts)
824: and are getting the reply (presumably ok) back.
825:
826: =head3 State=RequestingKey
827:
828: The ok has been received and we need to send the request for
829: an encryption key. Transition to writable for that.
830:
831: =head3 State=ReceivingKey
832:
833: The the key has been requested, now we are reading the new key.
834:
835: =head3 State=Idle
836:
837: The encryption key has been negotiated or we have finished
838: reading data from the a transaction. If the callback data have
839: a client as well as the socket information, then we are
840: doing a transaction and the data received are relayed to the client
841: before the socket is put on the idle list.
842:
843: =head3 State=SendingRequest
844:
845: I do not think this state can be received here, but if it is,
846: the appropriate thing to do is to transition to writable, and send
847: the request.
848:
849: =head3 State=ReceivingReply
850:
851: We finished sending the request to the server and now transition
852: to readable to receive the reply.
853:
854: The parameter to this function are:
855:
856: The event. Implicit in this is the watcher and its data. The data
857: contain at least the lond connection object and, if a
858: transaction is in progress, the socket attached to the local client.
859:
860: =cut
861:
862: sub LondReadable {
863:
864: my $Event = shift;
865: my $Watcher = $Event->w;
866: my $Socket = $Watcher->data;
867: my $client = undef;
868:
869: &Debug(6,"LondReadable called state = ".$Socket->GetState());
870:
871:
872: my $State = $Socket->GetState(); # All action depends on the state.
873:
874: SocketDump(6, $Socket);
875: my $status = $Socket->Readable();
876:
877: &Debug(2, "Socket->Readable returned: $status");
878:
879: if($status != 0) {
880: # bad return from socket read. Currently this means that
881: # The socket has become disconnected. We fail the transaction.
882:
883: Log("WARNING",
884: "Lond connection lost.");
885: my $state_on_exit = $Socket->GetState();
886: if(exists($ActiveTransactions{$Socket})) {
887: FailTransaction($ActiveTransactions{$Socket});
888: } else {
889: # Socket is connecting and failed... need to mark
890: # no longer connecting.
891: $LondConnecting = 0;
892: }
893: $Watcher->cancel();
894: if ($state_on_exit eq 'ReInitNoSSL') {
895: # SSL certificate verification failed, and insecure connection
896: # allowed. Send restart arg to KillSocket(), so EmptyQueue()
897: # is not called, as we still hope to process queued request.
898:
899: KillSocket($Socket,1);
900:
901: # Re-initiate creation of Lond Connection for use with queued
902: # request.
903:
904: ShowStatus("Connected to ".$RemoteHost);
905: Log("WARNING","No SSL channel (verification failed), will try with insecure channel");
906: &MakeLondConnection(1);
907:
908: } else {
909: KillSocket($Socket);
910: $ConnectionRetriesLeft--; # Counts as connection failure
911: }
912: return;
913: }
914: SocketDump(6,$Socket);
915:
916: $State = $Socket->GetState(); # Update in case of transition.
917: &Debug(6, "After read, state is ".$State);
918:
919: if($State eq "Initialized") {
920:
921:
922: } elsif ($State eq "ReInitNoSSL") {
923:
924: } elsif ($State eq "ChallengeReceived") {
925: # The challenge must be echoed back; The state machine
926: # in the connection takes care of setting that up. Just
927: # need to transition to writable:
928:
929: $Watcher->cb(\&LondWritable);
930: $Watcher->poll("w");
931:
932: } elsif ($State eq "ChallengeReplied") {
933:
934: } elsif ($State eq "RequestingVersion") {
935: # Need to ask for the version... that is writiability:
936:
937: $Watcher->cb(\&LondWritable);
938: $Watcher->poll("w");
939:
940: } elsif ($State eq "ReadingVersionString") {
941: # Read the rest of the version string...
942: } elsif ($State eq "SetHost") {
943: # Need to request the actual domain get set...
944:
945: $Watcher->cb(\&LondWritable);
946: $Watcher->poll("w");
947: } elsif ($State eq "HostSet") {
948: # Reading the 'ok' from the peer.
949:
950: } elsif ($State eq "RequestingKey") {
951: # The ok was received. Now we need to request the key
952: # That requires us to be writable:
953:
954: $Watcher->cb(\&LondWritable);
955: $Watcher->poll("w");
956:
957: } elsif ($State eq "ReceivingKey") {
958:
959: } elsif ($State eq "Idle") {
960:
961: if ($ConnectionCount == 1) {
962: # Write child Pid file to keep track of ssl and insecure
963: # connections
964:
965: &record_childpid($Socket);
966: }
967:
968: # This is as good a spot as any to get the peer version
969: # string:
970:
971: if($LondVersion eq "unknown") {
972: $LondVersion = $Socket->PeerVersion();
973: Log("INFO", "Connected to lond version: $LondVersion");
974: }
975: # If necessary, complete a transaction and then go into the
976: # idle queue.
977: # Note that a trasition to idle indicates a live lond
978: # on the other end so reset the connection retries.
979: #
980: $ConnectionRetriesLeft = $ConnectionRetries; # success resets the count
981: $Watcher->cancel();
982: if(exists($ActiveTransactions{$Socket})) {
983: Debug(5,"Completing transaction!!");
984: CompleteTransaction($Socket,
985: $ActiveTransactions{$Socket});
986: } else {
987: my $count = $Socket->GetClientData();
988: Log("SUCCESS", "Connection ".$count." to "
989: .$RemoteHost." now ready for action");
990: }
991: ServerToIdle($Socket); # Next work unit or idle.
992:
993: #
994: $LondConnecting = 0; # Best spot I can think of for this.
995: #
996:
997: } elsif ($State eq "SendingRequest") {
998: # We need to be writable for this and probably don't belong
999: # here inthe first place.
1000:
1001: Debug(6, "SendingRequest state encountered in readable");
1002: $Watcher->poll("w");
1003: $Watcher->cb(\&LondWritable);
1004:
1005: } elsif ($State eq "ReceivingReply") {
1006:
1007:
1008: } else {
1009: # Invalid state.
1010: Debug(4, "Invalid state in LondReadable");
1011: }
1012: }
1013:
1014: =pod
1015:
1016: =head2 LondWritable
1017:
1018: This function is called whenever a lond connection
1019: becomes writable while there is a writeable monitoring
1020: event. The action taken is very state dependent:
1021:
1022: =head3 State = Connected
1023:
1024: The connection is in the process of sending the 'init' hailing to the
1025: lond on the remote end. The Writable member of the connection object
1026: is called. On error, call ConnectionError to destroy the connection
1027: and remove it from the ActiveConnections hash.
1028:
1029: =head3 Initialized
1030:
1031: 'init' has been sent, writability monitoring is removed and
1032: readability monitoring is started with LondReadable as the callback.
1033:
1034: =head3 ChallengeReceived
1035:
1036: The connection has received the who are you challenge from the remote
1037: system, and is in the process of sending the challenge
1038: response. Writable is called.
1039:
1040: =head3 ChallengeReplied
1041:
1042: The connection has replied to the initial challenge The we switch to
1043: monitoring readability looking for the server to reply with 'ok'.
1044:
1045: =head3 RequestingKey
1046:
1047: The connection is in the process of requesting its encryption key.
1048: Writable is called.
1049:
1050: =head3 ReceivingKey
1051:
1052: The connection has sent the request for a key. Switch to readability
1053: monitoring to accept the key
1054:
1055: =head3 SendingRequest
1056:
1057: The connection is in the process of sending a request to the server.
1058: This request is part of a client transaction. All the states until
1059: now represent the client setup protocol. Writable is called.
1060:
1061: =head3 ReceivingReply
1062:
1063: The connection has sent a request. Now it must receive a reply.
1064: Readability monitoring is requested.
1065:
1066: This function is an event handler and therefore receives as
1067: a parameter the event that has fired. The data for the watcher
1068: of this event is a reference to a list of one or two elements,
1069: depending on state. The first (and possibly only) element is the
1070: socket. The second (present only if a request is in progress)
1071: is the socket on which to return a reply to the caller.
1072:
1073: =cut
1074:
1075: sub LondWritable {
1076: my $Event = shift;
1077: my $Watcher = $Event->w;
1078: my $Socket = $Watcher->data;
1079: my $State = $Socket->GetState();
1080:
1081: Debug(6,"LondWritable State = ".$State."\n");
1082:
1083:
1084: # Figure out what to do depending on the state of the socket:
1085:
1086:
1087:
1088:
1089: SocketDump(6,$Socket);
1090:
1091: # If the socket is writable, we must always write.
1092: # Only by writing will we undergo state transitions.
1093: # Old logic wrote in state specific code below, however
1094: # That forces us at least through another invocation of
1095: # this function after writability is possible again.
1096: # This logic also factors out common code for handling
1097: # write failures... in all cases, write failures
1098: # Kill the socket.
1099: # This logic makes the branches of the >big< if below
1100: # so that the writing states are actually NO-OPs.
1101:
1102: if ($Socket->Writable() != 0) {
1103: # The write resulted in an error.
1104: # We'll treat this as if the socket got disconnected:
1105: Log("WARNING", "Connection to ".$RemoteHost.
1106: " has been disconnected");
1107: if(exists($ActiveTransactions{$Socket})) {
1108: FailTransaction($ActiveTransactions{$Socket});
1109: } else {
1110: # In the process of conneting, so need to turn that off.
1111:
1112: $LondConnecting = 0;
1113: }
1114: $Watcher->cancel();
1115: KillSocket($Socket);
1116: return;
1117: }
1118:
1119:
1120:
1121: if ($State eq "Connected") {
1122:
1123: # "init" is being sent...
1124:
1125: } elsif ($State eq "Initialized") {
1126:
1127: # Now that init was sent, we switch
1128: # to watching for readability:
1129:
1130: $Watcher->cb(\&LondReadable);
1131: $Watcher->poll("r");
1132:
1133: } elsif ($State eq "ReInitNoSSL") {
1134:
1135: } elsif ($State eq "ChallengeReceived") {
1136: # We received the challenge, now we
1137: # are echoing it back. This is a no-op,
1138: # we're waiting for the state to change
1139:
1140: } elsif ($State eq "ChallengeReplied") {
1141: # The echo was sent back, so we switch
1142: # to watching readability.
1143:
1144: $Watcher->cb(\&LondReadable);
1145: $Watcher->poll("r");
1146: } elsif ($State eq "RequestingVersion") {
1147: # Sending the peer a version request...
1148:
1149: } elsif ($State eq "ReadingVersionString") {
1150: # Transition to read since we have sent the
1151: # version command and now just need to read the
1152: # version string from the peer:
1153:
1154: $Watcher->cb(\&LondReadable);
1155: $Watcher->poll("r");
1156:
1157: } elsif ($State eq "SetHost") {
1158: # Setting the remote domain...
1159:
1160: } elsif ($State eq "HostSet") {
1161: # Back to readable to get the ok.
1162:
1163: $Watcher->cb(\&LondReadable);
1164: $Watcher->poll("r");
1165:
1166:
1167: } elsif ($State eq "RequestingKey") {
1168: # At this time we're requesting the key.
1169: # again, this is essentially a no-op.
1170:
1171: } elsif ($State eq "ReceivingKey") {
1172: # Now we need to wait for the key
1173: # to come back from the peer:
1174:
1175: $Watcher->cb(\&LondReadable);
1176: $Watcher->poll("r");
1177:
1178: } elsif ($State eq "SendingRequest") {
1179:
1180: # At this time we are sending a request to the
1181: # peer... write the next chunk:
1182:
1183:
1184: } elsif ($State eq "ReceivingReply") {
1185: # The send has completed. Wait for the
1186: # data to come in for a reply.
1187: Debug(8,"Writable sent request/receiving reply");
1188: $Watcher->cb(\&LondReadable);
1189: $Watcher->poll("r");
1190:
1191: } else {
1192: # Control only passes here on an error:
1193: # the socket state does not match any
1194: # of the known states... so an error
1195: # must be logged.
1196:
1197: &Debug(4, "Invalid socket state ".$State."\n");
1198: }
1199:
1200: }
1201:
1202: =pod
1203:
1204: =cut
1205:
1206:
1207: sub QueueDelayed {
1208: Debug(3,"QueueDelayed called");
1209:
1210: my $path = "$perlvar{'lonSockDir'}/delayed";
1211:
1212: Debug(4, "Delayed path: ".$path);
1213: opendir(DIRHANDLE, $path);
1214:
1215: my $host_id_re = '(?:'.join('|',map {quotemeta($_)} (@all_host_ids)).')';
1216: my @alldelayed = grep(/\.$host_id_re$/, readdir(DIRHANDLE));
1217: closedir(DIRHANDLE);
1218: foreach my $dfname (sort(@alldelayed)) {
1219: my $reqfile = "$path/$dfname";
1220: my ($host_id) = ($dfname =~ /\.([^.]*)$/);
1221: Debug(4, "queueing ".$reqfile." for $host_id");
1222: my $Handle = IO::File->new($reqfile);
1223: my $cmd = <$Handle>;
1224: chomp $cmd; # There may or may not be a newline...
1225: $cmd = $cmd."\n"; # now for sure there's exactly one newline.
1226: my $Transaction = LondTransaction->new("sethost:$host_id:$cmd");
1227: $Transaction->SetDeferred($reqfile);
1228: QueueTransaction($Transaction);
1229: }
1230:
1231: }
1232:
1233: =pod
1234:
1235: =head2 MakeLondConnection
1236:
1237: Create a new lond connection object, and start it towards its initial
1238: idleness. Once idle, it becomes eligible to receive transactions
1239: from the work queue. If the work queue is not empty when the
1240: connection is completed and becomes idle, it will dequeue an entry and
1241: start off on it.
1242:
1243: =cut
1244:
1245: sub MakeLondConnection {
1246: my ($restart) = @_;
1247: Debug(4,"MakeLondConnection to ".GetServerHost()." on port "
1248: .GetServerPort());
1249:
1250: my $Connection = LondConnection->new(&GetServerHost(),
1251: &GetServerPort(),
1252: &GetHostId(),
1253: &GetDefHostId());
1254:
1255: if($Connection eq undef) {
1256: Log("CRITICAL","Failed to make a connection with lond.");
1257: $ConnectionRetriesLeft--;
1258: return 0; # Failure.
1259: } else {
1260: $LondConnecting = 1; # Connection in progress.
1261: # The connection needs to have writability
1262: # monitored in order to send the init sequence
1263: # that starts the whole authentication/key
1264: # exchange underway.
1265: #
1266: my $Socket = $Connection->GetSocket();
1267: if($Socket eq undef) {
1268: &child_exit(-1, "did not get a socket from the connection");
1269: } else {
1270: &Debug(9,"MakeLondConnection got socket: ".$Socket);
1271: }
1272:
1273: $Connection->SetTimeoutCallback(\&SocketTimeout);
1274:
1275: my $event = Event->io(fd => $Socket,
1276: poll => 'w',
1277: cb => \&LondWritable,
1278: data => $Connection,
1279: desc => 'Connection to lond server');
1280: $ActiveConnections{$Connection} = $event;
1281: if ($ConnectionCount == 0) {
1282: &SetupTimer; # Need to handle timeouts with connections...
1283: }
1284: unless ($restart) {
1285: $ConnectionCount++;
1286: }
1287: $Connection->SetClientData($ConnectionCount);
1288: Debug(4, "Connection count = ".$ConnectionCount);
1289: if($ConnectionCount == 1) { # First Connection:
1290: QueueDelayed;
1291: }
1292: Log("SUCCESS", "Created connection ".$ConnectionCount
1293: ." to host ".GetServerHost());
1294: return 1; # Return success.
1295: }
1296:
1297: }
1298:
1299: =pod
1300:
1301: =head2 StartRequest
1302:
1303: Starts a lond request going on a specified lond connection.
1304: parameters are:
1305:
1306: =item $Lond
1307:
1308: Connection to the lond that will send the transaction and receive the
1309: reply.
1310:
1311: =item $Client
1312:
1313: Connection to the client that is making this request. We got the
1314: request from this socket, and when the request has been relayed to
1315: lond and we get a reply back from lond it will get sent to this
1316: socket.
1317:
1318: =item $Request
1319:
1320: The text of the request to send.
1321:
1322: =cut
1323:
1324: sub StartRequest {
1325:
1326: my ($Lond, $Request) = @_;
1327:
1328: Debug(6, "StartRequest: ".$Request->getRequest());
1329:
1330: my $Socket = $Lond->GetSocket();
1331:
1332: $Request->Activate($Lond);
1333: $ActiveTransactions{$Lond} = $Request;
1334:
1335: $Lond->InitiateTransaction($Request->getRequest());
1336: my $event = Event->io(fd => $Socket,
1337: poll => "w",
1338: cb => \&LondWritable,
1339: data => $Lond,
1340: desc => "lond transaction connection");
1341: $ActiveConnections{$Lond} = $event;
1342: Debug(8," Start Request made watcher data with ".$event->data."\n");
1343: }
1344:
1345: =pod
1346:
1347: =head2 QueueTransaction
1348:
1349: If there is an idle lond connection, it is put to work doing this
1350: transaction. Otherwise, the transaction is placed in the work queue.
1351: If placed in the work queue and the maximum number of connections has
1352: not yet been created, a new connection will be started. Our goal is
1353: to eventually have a sufficient number of connections that the work
1354: queue will typically be empty. parameters are:
1355:
1356: =item Socket
1357:
1358: open on the lonc client.
1359:
1360: =item Request
1361:
1362: data to send to the lond.
1363:
1364: =cut
1365:
1366: sub QueueTransaction {
1367:
1368: my $requestData = shift; # This is a LondTransaction.
1369: my $cmd = $requestData->getRequest();
1370:
1371: Debug(6,"QueueTransaction: ".$cmd);
1372:
1373: my $LondSocket = $IdleConnections->pop();
1374: if(!defined $LondSocket) { # Need to queue request.
1375: Debug(5,"Must queue...");
1376: $WorkQueue->enqueue($requestData);
1377: Debug(5, "Queue Transaction startnew $ConnectionCount $LondConnecting");
1378: if(($ConnectionCount < $MaxConnectionCount) && (! $LondConnecting)) {
1379:
1380: if($ConnectionRetriesLeft > 0) {
1381: Debug(5,"Starting additional lond connection");
1382: if(&MakeLondConnection() == 0) {
1383: EmptyQueue(); # Fail transactions, can't make connection.
1384: CloseAllLondConnections; # Should all be closed but...
1385: }
1386: } else {
1387: ShowStatus(GetServerHost()." >>> DEAD !!!! <<<");
1388: $LondConnecting = 0;
1389: EmptyQueue(); # It's worse than that ... he's dead Jim.
1390: CloseAllLondConnections; # Should all be closed but..
1391: }
1392: }
1393: } else { # Can start the request:
1394: Debug(8,"Can start...");
1395: StartRequest($LondSocket, $requestData);
1396: }
1397: }
1398:
1399: #-------------------------- Lonc UNIX socket handling -------------------
1400: =pod
1401:
1402: =head2 ClientRequest
1403:
1404: Callback that is called when data can be read from the UNIX domain
1405: socket connecting us with an apache server process.
1406:
1407: =cut
1408:
1409: sub ClientRequest {
1410: Debug(6, "ClientRequest");
1411: my $event = shift;
1412: my $watcher = $event->w;
1413: my $socket = $watcher->fd;
1414: my $data = $watcher->data;
1415: my $thisread;
1416:
1417: Debug(9, " Watcher named: ".$watcher->desc);
1418:
1419: my $rv = $socket->recv($thisread, POSIX::BUFSIZ, 0);
1420: Debug(8, "rcv: data length = ".length($thisread)
1421: ." read =".$thisread);
1422: unless (defined $rv && length($thisread)) {
1423: # Likely eof on socket.
1424: Debug(5,"Client Socket closed on lonc for ".$RemoteHost);
1425: close($socket);
1426: $watcher->cancel();
1427: delete($ActiveClients{$socket});
1428: return;
1429: }
1430: Debug(8,"Data: ".$data." this read: ".$thisread);
1431: $data = $data.$thisread; # Append new data.
1432: $watcher->data($data);
1433: if($data =~ /\n$/) { # Request entirely read.
1434: if ($data eq "close_connection_exit\n") {
1435: Log("CRITICAL",
1436: "Request Close Connection ... exiting");
1437: CloseAllLondConnections();
1438: exit;
1439: } elsif ($data eq "reset_retries\n") {
1440: Log("INFO", "Resetting Connection Retries.");
1441: $ConnectionRetriesLeft = $ConnectionRetries;
1442: &UpdateStatus();
1443: my $Transaction = LondTransaction->new($data);
1444: $Transaction->SetClient($socket);
1445: StartClientReply($Transaction, "ok\n");
1446: $watcher->cancel();
1447: return;
1448: }
1449: Debug(8, "Complete transaction received: ".$data);
1450: if ($LogTransactions) {
1451: Log("SUCCESS", "Transaction: '$data'"); # Transaction has \n.
1452: }
1453: my $Transaction = LondTransaction->new($data);
1454: $Transaction->SetClient($socket);
1455: QueueTransaction($Transaction);
1456: $watcher->cancel(); # Done looking for input data.
1457: }
1458:
1459: }
1460:
1461: #
1462: # Accept a connection request for a client (lonc child) and
1463: # start up an event watcher to keep an eye on input from that
1464: # Event. This can be called both from NewClient and from
1465: # ChildProcess.
1466: # Parameters:
1467: # $socket - The listener socket.
1468: # Returns:
1469: # NONE
1470: # Side Effects:
1471: # An event is made to watch the accepted connection.
1472: # Active clients hash is updated to reflect the new connection.
1473: # The client connection count is incremented.
1474: #
1475: sub accept_client {
1476: my ($socket) = @_;
1477:
1478: Debug(8, "Entering accept for lonc UNIX socket\n");
1479: my $connection = $socket->accept(); # Accept the client connection.
1480: Debug(8,"Connection request accepted from "
1481: .GetPeername($connection, AF_UNIX));
1482:
1483:
1484: my $description = sprintf("Connection to lonc client %d",
1485: $ClientConnection);
1486: Debug(9, "Creating event named: ".$description);
1487: Event->io(cb => \&ClientRequest,
1488: poll => 'r',
1489: desc => $description,
1490: data => "",
1491: fd => $connection);
1492: $ActiveClients{$connection} = $ClientConnection;
1493: $ClientConnection++;
1494: }
1495:
1496: =pod
1497:
1498: =head2 NewClient
1499:
1500: Callback that is called when a connection is received on the unix
1501: socket for a new client of lonc. The callback is parameterized by the
1502: event.. which is a-priori assumed to be an io event, and therefore has
1503: an fd member that is the Listener socket. We accept the connection
1504: and register a new event on the readability of that socket:
1505:
1506: =cut
1507:
1508: sub NewClient {
1509: Debug(6, "NewClient");
1510: my $event = shift; # Get the event parameters.
1511: my $watcher = $event->w;
1512: my $socket = $watcher->fd; # Get the event' socket.
1513:
1514: &accept_client($socket);
1515: }
1516:
1517: =pod
1518:
1519: =head2 GetLoncSocketPath
1520:
1521: Returns the name of the UNIX socket on which to listen for client
1522: connections.
1523:
1524: =head2 Parameters:
1525:
1526: host (optional) - Name of the host socket to return.. defaults to
1527: the return from GetServerHost().
1528:
1529: =cut
1530:
1531: sub GetLoncSocketPath {
1532:
1533: my $host = GetServerHost(); # Default host.
1534: if (@_) {
1535: ($host) = @_; # Override if supplied.
1536: }
1537: return $UnixSocketDir."/".$host;
1538: }
1539:
1540: =pod
1541:
1542: =head2 GetServerHost
1543:
1544: Returns the host whose lond we talk with.
1545:
1546: =cut
1547:
1548: sub GetServerHost {
1549: return $RemoteHost; # Setup by the fork.
1550: }
1551:
1552: =pod
1553:
1554: =head2 GetHostId
1555:
1556: Returns the hostid whose lond we talk with.
1557:
1558: =cut
1559:
1560: sub GetHostId {
1561: return $RemoteHostId; # Setup by the fork.
1562: }
1563:
1564: =pod
1565:
1566: =head2 GetDefHostId
1567:
1568: Returns the default hostid for the node whose lond we talk with.
1569:
1570: =cut
1571:
1572: sub GetDefHostId { # Setup by the fork.
1573: return $RemoteDefHostId;
1574: }
1575:
1576: =pod
1577:
1578: =head2 GetServerPort
1579:
1580: Returns the lond port number.
1581:
1582: =cut
1583:
1584: sub GetServerPort {
1585: return $perlvar{londPort};
1586: }
1587:
1588: =pod
1589:
1590: =head2 SetupLoncListener
1591:
1592: Setup a lonc listener event. The event is called when the socket
1593: becomes readable.. that corresponds to the receipt of a new
1594: connection. The event handler established will accept the connection
1595: (creating a communications channel), that in turn will establish
1596: another event handler to subess requests.
1597:
1598: =head2 Parameters:
1599:
1600: host (optional) Name of the host to set up a unix socket to.
1601:
1602: =cut
1603:
1604: sub SetupLoncListener {
1605: my ($host,$SocketName) = @_;
1606: if (!$host) { $host = &GetServerHost(); }
1607: if (!$SocketName) { $SocketName = &GetLoncSocketPath($host); }
1608:
1609:
1610: unlink($SocketName);
1611:
1612: my $socket;
1613: unless ($socket =IO::Socket::UNIX->new(Local => $SocketName,
1614: Listen => 250,
1615: Type => SOCK_STREAM)) {
1616: if($I_am_child) {
1617: &child_exit(-1, "Failed to create a lonc listener socket");
1618: } else {
1619: die "Failed to create a lonc listner socket";
1620: }
1621: }
1622: return $socket;
1623: }
1624:
1625: #
1626: # Toggle transaction logging.
1627: # Implicit inputs:
1628: # LogTransactions
1629: # Implicit Outputs:
1630: # LogTransactions
1631: sub ToggleTransactionLogging {
1632: print STDERR "Toggle transaction logging...\n";
1633: if(!$LogTransactions) {
1634: $LogTransactions = 1;
1635: } else {
1636: $LogTransactions = 0;
1637: }
1638:
1639:
1640: Log("SUCCESS", "Toggled transaction logging: $LogTransactions \n");
1641: }
1642:
1643: =pod
1644:
1645: =head2 ChildStatus
1646:
1647: Child USR1 signal handler to report the most recent status
1648: into the status file.
1649:
1650: We also use this to reset the retries count in order to allow the
1651: client to retry connections with a previously dead server.
1652:
1653: =cut
1654:
1655: sub ChildStatus {
1656: my $event = shift;
1657: my $watcher = $event->w;
1658:
1659: Debug(2, "Reporting child status because : ".$watcher->data);
1660: my $docdir = $perlvar{'lonDocRoot'};
1661:
1662: open(LOG,">>$docdir/lon-status/loncstatus.txt");
1663: flock(LOG,LOCK_EX);
1664: print LOG $$."\t".$RemoteHost."\t".$Status."\t".
1665: $RecentLogEntry."\n";
1666: #
1667: # Write out information about each of the connections:
1668: #
1669: if ($DebugLevel > 2) {
1670: print LOG "Active connection statuses: \n";
1671: my $i = 1;
1672: print STDERR "================================= Socket Status Dump:\n";
1673: foreach my $item (keys %ActiveConnections) {
1674: my $Socket = $ActiveConnections{$item}->data;
1675: my $state = $Socket->GetState();
1676: print LOG "Connection $i State: $state\n";
1677: print STDERR "---------------------- Connection $i \n";
1678: $Socket->Dump(-1); # Ensure it gets dumped..
1679: $i++;
1680: }
1681: }
1682: flock(LOG,LOCK_UN);
1683: close(LOG);
1684: $ConnectionRetriesLeft = $ConnectionRetries;
1685: UpdateStatus();
1686: }
1687:
1688: =pod
1689:
1690: =head2 SignalledToDeath
1691:
1692: Called in response to a signal that causes a chid process to die.
1693:
1694: =cut
1695:
1696:
1697: sub SignalledToDeath {
1698: my $event = shift;
1699: my $watcher= $event->w;
1700:
1701: Debug(2,"Signalled to death! via ".$watcher->data);
1702: my ($signal) = $watcher->data;
1703: chomp($signal);
1704: Log("CRITICAL", "Abnormal exit. Child $$ for $RemoteHost "
1705: ."died through "."\"$signal\"");
1706: #LogPerm("F:lonc: $$ on $RemoteHost signalled to death: "
1707: # ."\"$signal\"");
1708: &clear_childpid($$);
1709: exit 0;
1710:
1711: }
1712:
1713: =pod
1714:
1715: =head2 ToggleDebug
1716:
1717: This sub toggles trace debugging on and off.
1718:
1719: =cut
1720:
1721: sub ToggleDebug {
1722: my $Current = $DebugLevel;
1723: $DebugLevel = $NextDebugLevel;
1724: $NextDebugLevel = $Current;
1725:
1726: Log("SUCCESS", "New debugging level for $RemoteHost now $DebugLevel");
1727:
1728: }
1729:
1730: =pod
1731:
1732: =head2 ChildProcess
1733:
1734: This sub implements a child process for a single lonc daemon.
1735: Optional parameter:
1736: $socket - if provided, this is a socket already open for listening
1737: on the client socket. Otherwise, a new listener is set up.
1738:
1739: =cut
1740:
1741: sub ChildProcess {
1742: # We've inherited all the
1743: # events of our parent and those have to be cancelled or else
1744: # all holy bloody chaos will result.. trust me, I already made
1745: # >that< mistake.
1746:
1747: my $host = GetServerHost();
1748: foreach my $listener (keys %parent_dispatchers) {
1749: my $watcher = $parent_dispatchers{$listener};
1750: my $s = $watcher->fd;
1751: if ($listener ne $host) { # Close everyone but me.
1752: Debug(5, "Closing listen socket for $listener");
1753: $s->close();
1754: }
1755: Debug(5, "Killing watcher for $listener");
1756:
1757: $watcher->cancel();
1758: delete($parent_dispatchers{$listener});
1759:
1760: }
1761:
1762: # kill off the parent's signal handlers too!
1763: #
1764:
1765: for my $handler (keys %parent_handlers) {
1766: my $watcher = $parent_handlers{$handler};
1767: $watcher->cancel();
1768: delete($parent_handlers{$handler});
1769: }
1770:
1771: $I_am_child = 1; # Seems like in spite of it all I may still getting
1772: # parent event dispatches.. flag I'm a child.
1773:
1774:
1775: #
1776: # Signals must be handled by the Event framework...
1777: #
1778:
1779: Event->signal(signal => "QUIT",
1780: cb => \&SignalledToDeath,
1781: data => "QUIT");
1782: Event->signal(signal => "HUP",
1783: cb => \&ChildStatus,
1784: data => "HUP");
1785: Event->signal(signal => "USR1",
1786: cb => \&ChildStatus,
1787: data => "USR1");
1788: Event->signal(signal => "USR2",
1789: cb => \&ToggleTransactionLogging);
1790: Event->signal(signal => "INT",
1791: cb => \&ToggleDebug,
1792: data => "INT");
1793:
1794: # Block the pipe signal we'll get when the socket disconnects. We detect
1795: # socket disconnection via send/receive failures. On disconnect, the
1796: # socket becomes readable .. which will force the disconnect detection.
1797:
1798: my $set = POSIX::SigSet->new(SIGPIPE);
1799: sigprocmask(SIG_BLOCK, $set);
1800:
1801: # Figure out if we got passed a socket or need to open one to listen for
1802: # client requests.
1803:
1804: my ($socket) = @_;
1805: if (!$socket) {
1806:
1807: $socket = SetupLoncListener();
1808: }
1809: # Establish an event to listen for client connection requests.
1810:
1811:
1812: Event->io(cb => \&NewClient,
1813: poll => 'r',
1814: desc => 'Lonc Listener Unix Socket',
1815: fd => $socket);
1816:
1817: $Event::DebugLevel = $DebugLevel;
1818:
1819: Debug(9, "Making initial lond connection for ".$RemoteHost);
1820:
1821: # Setup the initial server connection:
1822:
1823: # &MakeLondConnection(); // let first work request do it.
1824:
1825: # need to accept the connection since the event may not fire.
1826:
1827: &accept_client($socket);
1828:
1829: Debug(9,"Entering event loop");
1830: my $ret = Event::loop(); # Start the main event loop.
1831:
1832:
1833: &child_exit (-1,"Main event loop exited!!!");
1834: }
1835:
1836: # Create a new child for host passed in:
1837:
1838: sub CreateChild {
1839: my ($host, $hostid, $defhostid) = @_;
1840:
1841: my $sigset = POSIX::SigSet->new(SIGINT);
1842: sigprocmask(SIG_BLOCK, $sigset);
1843: $RemoteHost = $host;
1844: ShowStatus('Parent keeping the flock'); # Update time in status message.
1845: Log("CRITICAL", "Forking server for ".$host);
1846: my $pid = fork;
1847: if($pid) { # Parent
1848: $RemoteHost = "Parent";
1849: $ChildPid{$pid} = $host;
1850: sigprocmask(SIG_UNBLOCK, $sigset);
1851: undef(@all_host_ids);
1852: } else { # child.
1853: $RemoteHostId = $hostid;
1854: $RemoteDefHostId = $defhostid;
1855: ShowStatus("Connected to ".$RemoteHost);
1856: $SIG{INT} = 'DEFAULT';
1857: sigprocmask(SIG_UNBLOCK, $sigset);
1858: &ChildProcess(); # Does not return.
1859: }
1860: }
1861:
1862: # parent_client_connection:
1863: # Event handler that processes client connections for the parent process.
1864: # This sub is called when the parent is listening on a socket and
1865: # a connection request arrives. We must:
1866: # Start a child process to accept the connection request.
1867: # Kill our listen on the socket.
1868: # Parameter:
1869: # event - The event object that was created to monitor this socket.
1870: # event->w->fd is the socket.
1871: # Returns:
1872: # NONE
1873: #
1874: sub parent_client_connection {
1875: if ($I_am_child) {
1876: # Should not get here, but seem to anyway:
1877: &Debug(5," Child caught parent client connection event!!");
1878: my ($event) = @_;
1879: my $watcher = $event->w;
1880: $watcher->cancel(); # Try to kill it off again!!
1881: } else {
1882: &Debug(9, "parent_client_connection");
1883: my ($event) = @_;
1884: my $watcher = $event->w;
1885: my $socket = $watcher->fd;
1886: my $connection = $socket->accept(); # Accept the client connection.
1887: Event->io(cb => \&get_remote_hostname,
1888: poll => 'r',
1889: data => "",
1890: fd => $connection);
1891: }
1892: }
1893:
1894: sub get_remote_hostname {
1895: my ($event) = @_;
1896: my $watcher = $event->w;
1897: my $socket = $watcher->fd;
1898:
1899: my $thisread;
1900: my $rv = $socket->recv($thisread, POSIX::BUFSIZ, 0);
1901: Debug(8, "rcv: data length = ".length($thisread)." read =".$thisread);
1902: if (!defined($rv) || length($thisread) == 0) {
1903: # Likely eof on socket.
1904: Debug(5,"Client Socket closed on lonc for p_c_c");
1905: close($socket);
1906: $watcher->cancel();
1907: return;
1908: }
1909:
1910: my $data = $watcher->data().$thisread;
1911: $watcher->data($data);
1912: if($data =~ /\n$/) { # Request entirely read.
1913: chomp($data);
1914: } else {
1915: return;
1916: }
1917:
1918: &Debug(5,"Creating child for $data (parent_client_connection)");
1919: (my $hostname,my $lonid,@all_host_ids) = split(':',$data);
1920: $ChildHost{$hostname}++;
1921: if ($ChildHost{$hostname} == 1) {
1922: &CreateChild($hostname,$lonid,$all_host_ids[-1]);
1923: } else {
1924: &Log('WARNING',"Request for a second child on $hostname");
1925: }
1926: # Clean up the listen since now the child takes over until it exits.
1927: $watcher->cancel(); # Nolonger listening to this event
1928: $socket->send("done\n");
1929: $socket->close();
1930: }
1931:
1932: # parent_listen:
1933: # Opens a socket and starts a listen for the parent process on a client UNIX
1934: # domain socket.
1935: #
1936: # This involves:
1937: # Creating a socket for listen.
1938: # Removing any socket lock file
1939: # Adding an event handler for this socket becoming readable
1940: # To the parent's event dispatcher.
1941: # Parameters:
1942: # loncapa_host - LonCAPA cluster name of the host represented by the client
1943: # socket.
1944: # Returns:
1945: # NONE
1946: #
1947: sub parent_listen {
1948: my ($loncapa_host) = @_;
1949: Debug(5, "parent_listen: $loncapa_host");
1950:
1951: my ($socket,$file);
1952: if (!$loncapa_host) {
1953: $loncapa_host = 'common_parent';
1954: $file = $perlvar{'lonSockCreate'};
1955: } else {
1956: $file = &GetLoncSocketPath($loncapa_host);
1957: }
1958: $socket = &SetupLoncListener($loncapa_host,$file);
1959:
1960: $listening_to{$socket} = $loncapa_host;
1961: if (!$socket) {
1962: die "Unable to create a listen socket for $loncapa_host";
1963: }
1964:
1965: my $lock_file = $file.".lock";
1966: unlink($lock_file); # No problem if it doesn't exist yet [startup e.g.]
1967:
1968: my $watcher =
1969: Event->io(cb => \&parent_client_connection,
1970: poll => 'r',
1971: desc => "Parent listener unix socket ($loncapa_host)",
1972: data => "",
1973: fd => $socket);
1974: $parent_dispatchers{$loncapa_host} = $watcher;
1975:
1976: }
1977:
1978: sub parent_clean_up {
1979: my ($loncapa_host) = @_;
1980: Debug(1, "parent_clean_up: $loncapa_host");
1981:
1982: my $socket_file = &GetLoncSocketPath($loncapa_host);
1983: unlink($socket_file); # No problem if it doesn't exist yet [startup e.g.]
1984: my $lock_file = $socket_file.".lock";
1985: unlink($lock_file); # No problem if it doesn't exist yet [startup e.g.]
1986: }
1987:
1988:
1989:
1990: # This sub initiates a listen on the common unix domain lonc client socket.
1991: # loncnew starts up with no children, and only spawns off children when a
1992: # connection request occurs on the common client unix socket. The spawned
1993: # child continues to run until it has been idle a while at which point it
1994: # eventually exits and once more the parent picks up the listen.
1995: #
1996: # Parameters:
1997: # NONE
1998: # Implicit Inputs:
1999: # The configuration file that has been read in by LondConnection.
2000: # Returns:
2001: # NONE
2002: #
2003: sub listen_on_common_socket {
2004: Debug(5, "listen_on_common_socket");
2005: &parent_listen();
2006: }
2007:
2008: # server_died is called whenever a child process exits.
2009: # Since this is dispatched via a signal, we must process all
2010: # dead children until there are no more left. The action
2011: # is to:
2012: # - Remove the child from the bookeeping hashes
2013: # - Re-establish a listen on the unix domain socket associated
2014: # with that host.
2015: # Parameters:
2016: # The event, but we don't actually care about it.
2017: sub server_died {
2018: &Debug(9, "server_died called...");
2019:
2020: while(1) { # Loop until waitpid nowait fails.
2021: my $pid = waitpid(-1, WNOHANG);
2022: if($pid <= 0) {
2023: return; # Nothing left to wait for.
2024: }
2025: # need the host to restart:
2026:
2027: my $host = $ChildPid{$pid};
2028: if($host) { # It's for real...
2029: &Debug(9, "Caught sigchild for $host");
2030: &clear_childpid($pid);
2031: delete($ChildPid{$pid});
2032: delete($ChildHost{$host});
2033: &parent_clean_up($host);
2034:
2035: } else {
2036: &Debug(5, "Caught sigchild for pid not in hosts hash: $pid");
2037: }
2038: }
2039:
2040: }
2041:
2042: #
2043: # Parent process logic pass 1:
2044: # For each entry in the hosts table, we will
2045: # fork off an instance of ChildProcess to service the transactions
2046: # to that host. Each pid will be entered in a global hash
2047: # with the value of the key, the host.
2048: # The parent will then enter a loop to wait for process exits.
2049: # Each exit gets logged and the child gets restarted.
2050: #
2051:
2052: #
2053: # Fork and start in new session so hang-up isn't going to
2054: # happen without intent.
2055: #
2056:
2057:
2058:
2059:
2060:
2061:
2062: ShowStatus("Forming new session");
2063: my $childpid = fork;
2064: if ($childpid != 0) {
2065: sleep 4; # Give child a chacne to break to
2066: exit 0; # a new sesion.
2067: }
2068: #
2069: # Write my pid into the pid file so I can be located
2070: #
2071:
2072: ShowStatus("Parent writing pid file:");
2073: my $execdir = $perlvar{'lonDaemons'};
2074: open (PIDSAVE, ">$execdir/logs/lonc.pid");
2075: print PIDSAVE "$$\n";
2076: close(PIDSAVE);
2077:
2078:
2079:
2080: if (POSIX::setsid() < 0) {
2081: print "Could not create new session\n";
2082: exit -1;
2083: }
2084:
2085: ShowStatus("Forking node servers");
2086:
2087: Log("CRITICAL", "--------------- Starting children ---------------");
2088:
2089: LondConnection::ReadConfig; # Read standard config files.
2090:
2091: $RemoteHost = "[parent]";
2092: &listen_on_common_socket();
2093:
2094: $RemoteHost = "Parent Server";
2095:
2096: # Maintain the population:
2097:
2098: ShowStatus("Parent keeping the flock");
2099:
2100:
2101: # We need to setup a SIGChild event to handle the exit (natural or otherwise)
2102: # of the children.
2103:
2104: Event->signal(cb => \&server_died,
2105: desc => "Child exit handler",
2106: signal => "CHLD");
2107:
2108:
2109: # Set up all the other signals we set up.
2110:
2111: $parent_handlers{INT} = Event->signal(cb => \&Terminate,
2112: desc => "Parent INT handler",
2113: signal => "INT");
2114: $parent_handlers{TERM} = Event->signal(cb => \&Terminate,
2115: desc => "Parent TERM handler",
2116: signal => "TERM");
2117: $parent_handlers{HUP} = Event->signal(cb => \&KillThemAll,
2118: desc => "Parent HUP handler.",
2119: signal => "HUP");
2120: $parent_handlers{USR1} = Event->signal(cb => \&CheckKids,
2121: desc => "Parent USR1 handler",
2122: signal => "USR1");
2123: $parent_handlers{USR2} = Event->signal(cb => \&UpdateKids,
2124: desc => "Parent USR2 handler.",
2125: signal => "USR2");
2126:
2127: # Start procdesing events.
2128:
2129: $Event::DebugLevel = $DebugLevel;
2130: Debug(9, "Parent entering event loop");
2131: my $ret = Event::loop();
2132: die "Main Event loop exited: $ret";
2133:
2134: =pod
2135:
2136: =head1 CheckKids
2137:
2138: Since kids do not die as easily in this implementation
2139: as the previous one, there is no need to restart the
2140: dead ones (all dead kids get restarted when they die!!)
2141: The only thing this function does is to pass USR1 to the
2142: kids so that they report their status.
2143:
2144: =cut
2145:
2146: sub CheckKids {
2147: Debug(2, "Checking status of children");
2148: my $docdir = $perlvar{'lonDocRoot'};
2149: my $fh = IO::File->new(">$docdir/lon-status/loncstatus.txt");
2150: my $now=time;
2151: my $local=localtime($now);
2152: print $fh "LONC status $local - parent $$ \n\n";
2153: foreach my $host (keys %parent_dispatchers) {
2154: print $fh "LONC Parent process listening for $host\n";
2155: }
2156: foreach my $pid (keys %ChildPid) {
2157: Debug(2, "Sending USR1 -> $pid");
2158: kill 'USR1' => $pid; # Tell Child to report status.
2159: }
2160:
2161: }
2162:
2163: =pod
2164:
2165: =head1 UpdateKids
2166:
2167: parent's SIGUSR2 handler. This handler:
2168:
2169: =item
2170:
2171: Rereads the hosts file.
2172:
2173: =item
2174:
2175: Kills off (via sigint) children for hosts that have disappeared.
2176:
2177: =item
2178:
2179: QUITs children for hosts that already exist (this just forces a status display
2180: and resets the connection retry count for that host.
2181:
2182: =item
2183:
2184: Starts new children for hosts that have been added to the hosts.tab file since
2185: the start of the master program and maintains them.
2186:
2187: =cut
2188:
2189: sub UpdateKids {
2190:
2191: Log("INFO", "Updating connections via SIGUSR2");
2192:
2193: # I'm not sure what I was thinking in the first implementation.
2194: # someone will have to work hard to convince me the effect is any
2195: # different than Restart, especially now that we don't start up
2196: # per host servers automatically, may as well just restart.
2197: # The down side is transactions that are in flight will get timed out
2198: # (lost unless they are critical).
2199:
2200: &KillThemAll();
2201: LondConnection->ResetReadConfig();
2202: ShowStatus('Parent keeping the flock');
2203: }
2204:
2205:
2206: =pod
2207:
2208: =head1 Restart
2209:
2210: Signal handler for HUP... all children are killed and
2211: we self restart. This is an el-cheapo way to re-read
2212: the config file.
2213:
2214: =cut
2215:
2216: sub Restart {
2217: &KillThemAll; # First kill all the children.
2218: LondConnection->ResetReadConfig();
2219: Log("CRITICAL", "Restarting");
2220: my $execdir = $perlvar{'lonDaemons'};
2221: unlink("$execdir/logs/lonc.pid");
2222: exec("$executable");
2223: }
2224:
2225: =pod
2226:
2227: =head1 KillThemAll
2228:
2229: Signal handler that kills all children by sending them a
2230: SIGHUP. Responds to sigint and sigterm.
2231:
2232: =cut
2233:
2234: sub KillThemAll {
2235: Debug(2, "Kill them all!!");
2236:
2237: #local($SIG{CHLD}) = 'IGNORE';
2238: # Our children >will< die.
2239: # but we need to catch their death and cleanup after them in case this is
2240: # a restart set of kills
2241: my @allpids = keys(%ChildPid);
2242: foreach my $pid (@allpids) {
2243: my $serving = $ChildPid{$pid};
2244: ShowStatus("Nicely Killing lonc for $serving pid = $pid");
2245: Log("CRITICAL", "Nicely Killing lonc for $serving pid = $pid");
2246: kill 'QUIT' => $pid;
2247: &clear_childpid($pid);
2248: }
2249: ShowStatus("Finished killing child processes off.");
2250: }
2251:
2252:
2253: #
2254: # Kill all children via KILL. Just in case the
2255: # first shot didn't get them.
2256:
2257: sub really_kill_them_all_dammit
2258: {
2259: Debug(2, "Kill them all Dammit");
2260: local($SIG{CHLD} = 'IGNORE'); # In case some purist reenabled them.
2261: foreach my $pid (keys %ChildPid) {
2262: my $serving = $ChildPid{$pid};
2263: &ShowStatus("Nastily killing lonc for $serving pid = $pid");
2264: Log("CRITICAL", "Nastily killing lonc for $serving pid = $pid");
2265: kill 'KILL' => $pid;
2266: delete($ChildPid{$pid});
2267: delete($ChildKeyMode{$pid});
2268: my $execdir = $perlvar{'lonDaemons'};
2269: unlink("$execdir/logs/lonc.pid");
2270: }
2271: }
2272:
2273: =pod
2274:
2275: =head1 Terminate
2276:
2277: Terminate the system.
2278:
2279: =cut
2280:
2281: sub Terminate {
2282: &Log("CRITICAL", "Asked to kill children.. first be nice...");
2283: &KillThemAll;
2284: #
2285: # By now they really should all be dead.. but just in case
2286: # send them all SIGKILL's after a bit of waiting:
2287:
2288: sleep(4);
2289: &Log("CRITICAL", "Now kill children nasty");
2290: &really_kill_them_all_dammit;
2291: Log("CRITICAL","Master process exiting");
2292: exit 0;
2293:
2294: }
2295:
2296: =pod
2297:
2298: =cut
2299:
2300: sub my_hostname {
2301: use Sys::Hostname::FQDN();
2302: my $name = Sys::Hostname::FQDN::fqdn();
2303: &Debug(9,"Name is $name");
2304: return $name;
2305: }
2306:
2307: sub record_childpid {
2308: my ($Socket) = @_;
2309: my $docdir = $perlvar{'lonDocRoot'};
2310: my $authmode = $Socket->GetKeyMode();
2311: my $peer = $Socket->PeerLoncapaHim();
2312: if (($authmode eq 'ssl') || ($authmode eq 'insecure')) {
2313: my $childpid = $$;
2314: if ($childpid) {
2315: unless (exists($ChildKeyMode{$childpid})) {
2316: $ChildKeyMode{$childpid} = $authmode;
2317: }
2318: if (-d "$docdir/lon-status/loncchld") {
2319: unless (-e "$docdir/lon-status/loncchld/$childpid") {
2320: if (open (my $pidfh,'>',"$docdir/lon-status/loncchld/$childpid")) {
2321: print $pidfh "$peer:$authmode\n";
2322: close($pidfh);
2323: }
2324: }
2325: }
2326: }
2327: }
2328: return;
2329: }
2330:
2331: sub clear_childpid {
2332: my ($childpid) = @_;
2333: my $docdir = $perlvar{'lonDocRoot'};
2334: if (-d "$docdir/lon-status/loncchld") {
2335: if ($childpid =~ /^\d+$/) {
2336: if (($ChildKeyMode{$childpid} eq 'insecure') ||
2337: ($ChildKeyMode{$childpid} eq 'ssl')) {
2338: if (-e "$docdir/lon-status/loncchld/$childpid") {
2339: unlink("$docdir/lon-status/loncchld/$childpid");
2340: }
2341: }
2342: }
2343: }
2344: if (exists($ChildKeyMode{$childpid})) {
2345: delete($ChildKeyMode{$childpid});
2346: }
2347: return;
2348: }
2349:
2350: =pod
2351:
2352: =head1 Theory
2353:
2354: The event class is used to build this as a single process with an
2355: event driven model. The following events are handled:
2356:
2357: =item UNIX Socket connection Received
2358:
2359: =item Request data arrives on UNIX data transfer socket.
2360:
2361: =item lond connection becomes writable.
2362:
2363: =item timer fires at 1 second intervals.
2364:
2365: All sockets are run in non-blocking mode. Timeouts managed by the timer
2366: handler prevents hung connections.
2367:
2368: Key data structures:
2369:
2370: =item RequestQueue
2371:
2372: A queue of requests received from UNIX sockets that are
2373: waiting for a chance to be forwarded on a lond connection socket.
2374:
2375: =item ActiveConnections
2376:
2377: A hash of lond connections that have transactions in process that are
2378: available to be timed out.
2379:
2380: =item ActiveTransactions
2381:
2382: A hash indexed by lond connections that contain the client reply
2383: socket for each connection that has an active transaction on it.
2384:
2385: =item IdleConnections
2386:
2387: A hash of lond connections that have no work to do. These connections
2388: can be closed if they are idle for a long enough time.
2389:
2390: =cut
2391:
2392: =pod
2393:
2394: =head1 Log messages
2395:
2396: The following is a list of log messages that can appear in the
2397: lonc.log file. Each log file has a severity and a message.
2398:
2399: =over 2
2400:
2401: =item Warning A socket timeout was detected
2402:
2403: If there are pending transactions in the socket's queue,
2404: they are failed (saved if critical). If the connection
2405: retry count gets exceeded by this, the
2406: remote host is marked as dead.
2407: Called when timeouts occurred during the connection and
2408: connection dialog with a remote host.
2409:
2410: =item Critical Host makred DEAD <hostname>
2411:
2412: The numer of retry counts for contacting a host was
2413: exceeded. The host is marked dead an no
2414: further attempts will be made by that child.
2415:
2416: =item Info lonc pipe client hung up on us
2417:
2418: Write to the client pipe indicated no data transferred
2419: Socket to remote host is shut down. Reply to the client
2420: is discarded. Note: This is commented out in &ClientWriteable
2421:
2422: =item Success Reply from lond: <data>
2423:
2424: Can be enabled for debugging by setting LogTransactions to nonzero.
2425: Indicates a successful transaction with lond, <data> is the data received
2426: from the remote lond.
2427:
2428: =item Success A delayed transaction was completed
2429:
2430: A transaction that must be reliable was executed and completed
2431: as lonc restarted. This is followed by a mesage of the form
2432:
2433: S: client-name : request
2434:
2435: =item WARNING Failing transaction <cmd>:<subcmd>
2436:
2437: Transaction failed on a socket, but the failure retry count for the remote
2438: node has not yet been exhausted (the node is not yet marked dead).
2439: cmd is the command, subcmd is the subcommand. This results from a con_lost
2440: when communicating with lond.
2441:
2442: =item WARNING Shutting down a socket
2443:
2444: Called when a socket is being closed to lond. This is emitted both when
2445: idle pruning is being done and when the socket has been disconnected by the remote.
2446:
2447: =item WARNING Lond connection lost.
2448:
2449: Called when a read from lond's socket failed indicating lond has closed the
2450: connection or died. This should be followed by one or more
2451:
2452: "WARNING Failing transaction..." msgs for each in-flight or queued transaction.
2453:
2454: =item WARNING No SSL channel (verification failed), will try with insecure channel.
2455:
2456: Called when promotion of a socket to SSL failed because SSL certificate verification failed.
2457: Domain configuration must also permit insecure channel use for key exchange. Connection
2458: negotiation will start again from the beginning, but with Authentication Mode not set to ssl.
2459:
2460: =item INFO Connected to lond version: <version>
2461:
2462: When connection negotiation is complete, the lond version is requested and logged here.
2463:
2464: =item SUCCESS Connection n to host now ready for action
2465:
2466: Emitted when connection has been completed with lond. n is then number of
2467: concurrent connections and host, the host to which the connection has just
2468: been established.
2469:
2470: =item WARNING Connection to host has been disconnected
2471:
2472: Write to a lond resulted in failure status. Connection to lond is dropped.
2473:
2474: =item SUCCESS Created connection n to host host
2475:
2476: Initial connection request to host..(before negotiation).
2477:
2478: =item CRITICAL Request Close Connection ... exiting
2479:
2480: Client has sent "close_connection_exit" The loncnew server is exiting.
2481:
2482: =item INFO Resetting Connection Retries
2483:
2484: Client has sent "reset_retries" The lond connection retries are reset to zero for the
2485: corresponding lond.
2486:
2487: =item SUCCESS Transaction <data>
2488:
2489: Only emitted if the global variable $LogTransactions was set to true.
2490: A client has requested a lond transaction <data> is the contents of the request.
2491:
2492: =item SUCCESS Toggled transaction logging <LogTransactions>
2493:
2494: The state of the $LogTransactions global has been toggled, and its current value
2495: (after being toggled) is displayed. When non zero additional logging of transactions
2496: is enabled for debugging purposes. Transaction logging is toggled on receipt of a USR2
2497: signal.
2498:
2499: =item CRITICAL Abnormal exit. Child <pid> for <host> died thorugh signal.
2500:
2501: QUIT signal received. lonc child process is exiting.
2502:
2503: =item SUCCESS New debugging level for <RemoteHost> now <DebugLevel>
2504:
2505: Debugging toggled for the host loncnew is talking with.
2506: Currently debugging is a level based scheme with higher number
2507: conveying more information. The daemon starts out at
2508: DebugLevel 0 and can toggle back and forth between that and
2509: DebugLevel 2 These are controlled by
2510: the global variables $DebugLevel and $NextDebugLevel
2511: The debug level can go up to 9.
2512: SIGINT toggles the debug level. The higher the debug level the
2513: more debugging information is spewed. See the Debug
2514: sub in loncnew.
2515:
2516: =item CRITICAL Forking server for host
2517:
2518: A child is being created to service requests for the specified host.
2519:
2520:
2521: =item WARNING Request for a second child on hostname
2522:
2523: Somehow loncnew was asked to start a second child on a host that already had a child
2524: servicing it. This request is not honored, but themessage is emitted. This could happen
2525: due to a race condition. When a client attempts to contact loncnew for a new host, a child
2526: is forked off to handle the requests for that server. The parent then backs off the Unix
2527: domain socket leaving it for the child to service all requests. If in the time between
2528: creating the child, and backing off, a new connection request comes in to the unix domain
2529: socket, this could trigger (unlikely but remotely possible),.
2530:
2531: =item CRITICAL ------ Starting Children ----
2532:
2533: This message should probably be changed to "Entering event loop" as the loncnew only starts
2534: children as needed. This message is emitted as new events are established and
2535: the event processing loop is entered.
2536:
2537: =item INFO Updating connections via SIGUSR2
2538:
2539: SIGUSR2 received. The original code would kill all clients, re-read the host file,
2540: then restart children for each host. Now that children are started on demand, this
2541: just kills all child processes and lets requests start them as needed again.
2542:
2543:
2544: =item CRITICAL Restarting
2545:
2546: SigHUP received. all the children are killed and the script exec's itself to start again.
2547:
2548: =item CRITICAL Nicely killing lonc for host pid = <pid>
2549:
2550: Attempting to kill the child that is serving the specified host (pid given) cleanly via
2551: SIGQUIT. The child should handle that, clean up nicely and exit.
2552:
2553: =item CRITICAL Nastily killing lonc for host pid = <pid>
2554:
2555: The child specified did not die when requested via SIGQUIT. Therefore it is killed
2556: via SIGKILL.
2557:
2558: =item CRITICAL Asked to kill children.. first be nice..
2559:
2560: In the parent's INT handler. INT kills the child processes. This inidicate loncnew
2561: is about to attempt to kill all known children via SIGQUIT. This message should be followed
2562: by one "Nicely killing" message for each extant child.
2563:
2564: =item CRITICAL Now kill children nasty
2565:
2566: In the parent's INT handler. remaining children are about to be killed via
2567: SIGKILL. Should be followed by a Nastily killing... for each lonc child that
2568: refused to die.
2569:
2570: =item CRITICAL Master process exiting
2571:
2572: In the parent's INT handler. just prior to the exit 0 call.
2573:
2574: =back
2575:
2576: =cut
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