--- loncom/lond 2001/12/22 21:46:02 1.62
+++ loncom/lond 2002/03/27 04:07:02 1.75
@@ -2,7 +2,7 @@
# The LearningOnline Network
# lond "LON Daemon" Server (port "LOND" 5663)
#
-# $Id: lond,v 1.62 2001/12/22 21:46:02 www Exp $
+# $Id: lond,v 1.75 2002/03/27 04:07:02 foxr Exp $
#
# Copyright Michigan State University Board of Trustees
#
@@ -46,7 +46,13 @@
# 11/26,11/27 Gerd Kortemeyer
# 12/20 Scott Harrison
# 12/22 Gerd Kortemeyer
-#
+# YEAR=2002
+# 01/20/02,02/05 Gerd Kortemeyer
+# 02/05 Guy Albertelli
+# 02/07 Scott Harrison
+# 02/12 Gerd Kortemeyer
+# 02/19 Matthew Hall
+# 02/25 Gerd Kortemeyer
###
# based on "Perl Cookbook" ISBN 1-56592-243-3
@@ -84,6 +90,10 @@ sub catchexception {
die($error);
}
+sub timeout {
+ &logthis("CRITICAL: TIME OUT ".$$."");
+ &catchexception('Timeout');
+}
# -------------------------------- Set signal handlers to record abnormal exits
$SIG{'QUIT'}=\&catchexception;
@@ -131,7 +141,7 @@ open (CONFIG,"$perlvar{'lonTabDir'}/host
while ($configline=) {
my ($id,$domain,$role,$name,$ip)=split(/:/,$configline);
- chomp($ip);
+ chomp($ip); $ip=~s/\D+$//;
$hostid{$ip}=$id;
if ($id eq $perlvar{'lonHostID'}) { $thisserver=$name; }
$PREFORK++;
@@ -150,7 +160,7 @@ $server = IO::Socket::INET->new(LocalPor
# global variables
-$MAX_CLIENTS_PER_CHILD = 5; # number of clients each child should
+$MAX_CLIENTS_PER_CHILD = 50; # number of clients each child should
# process
%children = (); # keys are current child process IDs
$children = 0; # current number of children
@@ -158,9 +168,13 @@ $children = 0; # cu
sub REAPER { # takes care of dead children
$SIG{CHLD} = \&REAPER;
my $pid = wait;
- $children --;
- &logthis("Child $pid died");
- delete $children{$pid};
+ if (defined($children{$pid})) {
+ &logthis("Child $pid died");
+ $children --;
+ delete $children{$pid};
+ } else {
+ &logthis("Unknown Child $pid died");
+ }
}
sub HUNTSMAN { # signal handler for SIGINT
@@ -187,6 +201,7 @@ sub checkchildren {
&initnewstatus();
&logstatus();
&logthis('Going to check on the children');
+ $docdir=$perlvar{'lonDocRoot'};
foreach (sort keys %children) {
sleep 1;
unless (kill 'USR1' => $_) {
@@ -194,6 +209,18 @@ sub checkchildren {
&logstatus($$.' is dead');
}
}
+ sleep 5;
+ foreach (sort keys %children) {
+ unless (-e "$docdir/lon-status/londchld/$_.txt") {
+ &logthis('Child '.$_.' did not respond');
+ kill 9 => $_;
+ $emailto="$perlvar{'lonAdmEMail'},$perlvar{'lonSysEMail'}";
+ $subj="LON: $perlvar{'lonHostID'} killed lond process $_";
+ my $result=`echo 'Killed lond process $_.' | mailto $emailto -s '$subj' > /dev/null`;
+ $execdir=$perlvar{'lonDaemons'};
+ $result=`/bin/cp $execdir/logs/lond.log $execdir/logs/lond.log.$_`
+ }
+ }
}
# --------------------------------------------------------------------- Logging
@@ -212,8 +239,16 @@ sub logthis {
sub logstatus {
my $docdir=$perlvar{'lonDocRoot'};
+ {
my $fh=IO::File->new(">>$docdir/lon-status/londstatus.txt");
print $fh $$."\t".$status."\t".$lastlog."\n";
+ $fh->close();
+ }
+ {
+ my $fh=IO::File->new(">$docdir/lon-status/londchld/$$.txt");
+ print $fh $status."\n".$lastlog."\n".time;
+ $fh->close();
+ }
}
sub initnewstatus {
@@ -222,6 +257,11 @@ sub initnewstatus {
my $now=time;
my $local=localtime($now);
print $fh "LOND status $local - parent $$\n\n";
+ opendir(DIR,"$docdir/lon-status/londchld");
+ while ($filename=readdir(DIR)) {
+ unlink("$docdir/lon-status/londchld/$filename");
+ }
+ closedir(DIR);
}
# -------------------------------------------------------------- Status setting
@@ -261,10 +301,10 @@ sub reconlonc {
if (kill 0 => $loncpid) {
&logthis("lonc at pid $loncpid responding, sending USR1");
kill USR1 => $loncpid;
- sleep 1;
+ sleep 5;
if (-e "$peerfile") { return; }
&logthis("$peerfile still not there, give it another try");
- sleep 5;
+ sleep 10;
if (-e "$peerfile") { return; }
&logthis(
"WARNING: $peerfile still not there, giving up");
@@ -302,6 +342,7 @@ sub reply {
if ($answer eq 'con_lost') {
$answer=subreply("ping",$server);
if ($answer ne $server) {
+ &logthis("sub reply: answer != server");
&reconlonc("$perlvar{'lonSockDir'}/$server");
}
$answer=subreply($cmd,$server);
@@ -431,6 +472,7 @@ sub make_new_child {
# Child can *not* return from this subroutine.
$SIG{INT} = 'DEFAULT'; # make SIGINT kill us as it did before
$SIG{USR1}= \&logstatus;
+ $SIG{ALRM}= \&timeout;
$lastlog='Forked ';
$status='Forked';
@@ -490,7 +532,8 @@ sub make_new_child {
}
if ($clientok) {
# ---------------- New known client connecting, could mean machine online again
- &reconlonc("$perlvar{'lonSockDir'}/$hostid{$clientip}");
+
+ # &reconlonc("$perlvar{'lonSockDir'}/$hostid{$clientip}");
&logthis(
"Established connection: $hostid{$clientip}");
&status('Will listen to '.$hostid{$clientip});
@@ -499,6 +542,7 @@ sub make_new_child {
chomp($userinput);
&status('Processing '.$hostid{$clientip}.': '.$userinput);
my $wasenc=0;
+ alarm(120);
# ------------------------------------------------------------ See if encrypted
if ($userinput =~ /^enc/) {
if ($cipher) {
@@ -512,8 +556,9 @@ sub make_new_child {
}
$userinput=substr($userinput,0,$cmdlength);
$wasenc=1;
- }
}
+ }
+
# ------------------------------------------------------------- Normal commands
# ------------------------------------------------------------------------ ping
if ($userinput =~ /^ping/) {
@@ -600,10 +645,13 @@ sub make_new_child {
$pwdcorrect=!$?;
}
} elsif ($howpwd eq 'krb4') {
+ $null=pack("C",0);
+ unless ($upass=~/$null/) {
$pwdcorrect=(
Authen::Krb4::get_pw_in_tkt($uname,"",
$contentpwd,'krbtgt',$contentpwd,1,
$upass) == 0);
+ } else { $pwdcorrect=0; }
} elsif ($howpwd eq 'localauth') {
$pwdcorrect=&localauth::localauth($uname,$upass,
$contentpwd);
@@ -627,7 +675,8 @@ sub make_new_child {
chomp($npass);
$upass=&unescape($upass);
$npass=&unescape($npass);
- my $proname=propath($udom,$uname);
+ &logthis("Trying to change password for $uname");
+ my $proname=propath($udom,$uname);
my $passfilename="$proname/passwd";
if (-e $passfilename) {
my $realpasswd;
@@ -642,11 +691,42 @@ sub make_new_child {
my $ncpass=crypt($npass,$salt);
{ my $pf = IO::File->new(">$passfilename");
print $pf "internal:$ncpass\n"; }
+ &logthis("Result of password change for $uname: pwchange_success");
print $client "ok\n";
} else {
print $client "non_authorized\n";
}
- } else {
+ } elsif ($howpwd eq 'unix') {
+ # Unix means we have to access /etc/password
+ # one way or another.
+ # First: Make sure the current password is
+ # correct
+ $contentpwd=(getpwnam($uname))[1];
+ my $pwdcorrect = "0";
+ my $pwauth_path="/usr/local/sbin/pwauth";
+ unless ($contentpwd eq 'x') {
+ $pwdcorrect=
+ (crypt($upass,$contentpwd) eq $contentpwd);
+ } elsif (-e $pwauth_path) {
+ open PWAUTH, "|$pwauth_path" or
+ die "Cannot invoke authentication";
+ print PWAUTH "$uname\n$upass\n";
+ close PWAUTH;
+ $pwdcorrect=!$?;
+ }
+ if ($pwdcorrect) {
+ my $execdir=$perlvar{'lonDaemons'};
+ my $pf = IO::File->new("|$execdir/lcpasswd");
+ print $pf "$uname\n$npass\n$npass\n";
+ close $pf;
+ my $result = ($?>0 ? 'pwchange_failure'
+ : 'ok');
+ &logthis("Result of password change for $uname: $result");
+ print $client "$result\n";
+ } else {
+ print $client "non_authorized\n";
+ }
+ } else {
print $client "auth_mode_error\n";
}
} else {
@@ -677,7 +757,7 @@ sub make_new_child {
$fpnow.='/'.$fpparts[$i];
unless (-e $fpnow) {
unless (mkdir($fpnow,0777)) {
- $fperror="error:$!\n";
+ $fperror="error:$!";
}
}
}
@@ -1335,6 +1415,7 @@ sub make_new_child {
print $client "unknown_cmd\n";
}
# -------------------------------------------------------------------- complete
+ alarm(0);
&status('Listening to '.$hostid{$clientip});
}
# --------------------------------------------- client unknown or fishy, refuse
@@ -1343,15 +1424,15 @@ sub make_new_child {
$client->close();
&logthis("WARNING: "
."Rejected client $clientip, closing connection");
- }
- &logthis("CRITICAL: "
- ."Disconnect from $clientip ($hostid{$clientip})");
+ }
+ }
+
# =============================================================================
- }
-
+
+ &logthis("CRITICAL: "
+ ."Disconnect from $clientip ($hostid{$clientip})");
# tidy up gracefully and finish
- $client->close();
$server->close();
# this exit is VERY important, otherwise the child will become
@@ -1369,16 +1450,284 @@ lond - "LON Daemon" Server (port "LOND"
=head1 SYNOPSIS
-Should only be run as user=www. Invoked by loncron.
+Usage: B
+
+Should only be run as user=www. This is a command-line script which
+is invoked by B. There is no expectation that a typical user
+will manually start B from the command-line. (In other words,
+DO NOT START B YOURSELF.)
=head1 DESCRIPTION
+There are two characteristics associated with the running of B,
+PROCESS MANAGEMENT (starting, stopping, handling child processes)
+and SERVER-SIDE ACTIVITIES (password authentication, user creation,
+subscriptions, etc). These are described in two large
+sections below.
+
+B
+
Preforker - server who forks first. Runs as a daemon. HUPs.
Uses IDEA encryption
-=head1 README
+B forks off children processes that correspond to the other servers
+in the network. Management of these processes can be done at the
+parent process level or the child process level.
+
+B is the location of log messages.
+
+The process management is now explained in terms of linux shell commands,
+subroutines internal to this code, and signal assignments:
+
+=over 4
+
+=item *
+
+PID is stored in B
+
+This is the process id number of the parent B process.
+
+=item *
+
+SIGTERM and SIGINT
+
+Parent signal assignment:
+ $SIG{INT} = $SIG{TERM} = \&HUNTSMAN;
+
+Child signal assignment:
+ $SIG{INT} = 'DEFAULT'; (and SIGTERM is DEFAULT also)
+(The child dies and a SIGALRM is sent to parent, awaking parent from slumber
+ to restart a new child.)
+
+Command-line invocations:
+ B B<-s> SIGTERM I
+ B B<-s> SIGINT I
+
+Subroutine B:
+ This is only invoked for the B parent I.
+This kills all the children, and then the parent.
+The B file is cleared.
+
+=item *
+
+SIGHUP
+
+Current bug:
+ This signal can only be processed the first time
+on the parent process. Subsequent SIGHUP signals
+have no effect.
+
+Parent signal assignment:
+ $SIG{HUP} = \&HUPSMAN;
+
+Child signal assignment:
+ none (nothing happens)
+
+Command-line invocations:
+ B B<-s> SIGHUP I
+
+Subroutine B:
+ This is only invoked for the B parent I,
+This kills all the children, and then the parent.
+The B file is cleared.
+
+=item *
+
+SIGUSR1
+
+Parent signal assignment:
+ $SIG{USR1} = \&USRMAN;
+
+Child signal assignment:
+ $SIG{USR1}= \&logstatus;
+
+Command-line invocations:
+ B B<-s> SIGUSR1 I
+
+Subroutine B:
+ When invoked for the B parent I,
+SIGUSR1 is sent to all the children, and the status of
+each connection is logged.
+
+=item *
+
+SIGCHLD
+
+Parent signal assignment:
+ $SIG{CHLD} = \&REAPER;
+
+Child signal assignment:
+ none
+
+Command-line invocations:
+ B B<-s> SIGCHLD I
+
+Subroutine B:
+ This is only invoked for the B parent I.
+Information pertaining to the child is removed.
+The socket port is cleaned up.
+
+=back
+
+B
+
+Server-side information can be accepted in an encrypted or non-encrypted
+method.
+
+=over 4
+
+=item ping
-Not yet written.
+Query a client in the hosts.tab table; "Are you there?"
+
+=item pong
+
+Respond to a ping query.
+
+=item ekey
+
+Read in encrypted key, make cipher. Respond with a buildkey.
+
+=item load
+
+Respond with CPU load based on a computation upon /proc/loadavg.
+
+=item currentauth
+
+Reply with current authentication information (only over an
+encrypted channel).
+
+=item auth
+
+Only over an encrypted channel, reply as to whether a user's
+authentication information can be validated.
+
+=item passwd
+
+Allow for a password to be set.
+
+=item makeuser
+
+Make a user.
+
+=item passwd
+
+Allow for authentication mechanism and password to be changed.
+
+=item home
+
+Respond to a question "are you the home for a given user?"
+
+=item update
+
+Update contents of a subscribed resource.
+
+=item unsubscribe
+
+The server is unsubscribing from a resource.
+
+=item subscribe
+
+The server is subscribing to a resource.
+
+=item log
+
+Place in B
+
+=item put
+
+stores hash in namespace
+
+=item rolesput
+
+put a role into a user's environment
+
+=item get
+
+returns hash with keys from array
+reference filled in from namespace
+
+=item eget
+
+returns hash with keys from array
+reference filled in from namesp (encrypts the return communication)
+
+=item rolesget
+
+get a role from a user's environment
+
+=item del
+
+deletes keys out of array from namespace
+
+=item keys
+
+returns namespace keys
+
+=item dump
+
+dumps the complete (or key matching regexp) namespace into a hash
+
+=item store
+
+stores hash permanently
+for this url; hashref needs to be given and should be a \%hashname; the
+remaining args aren't required and if they aren't passed or are '' they will
+be derived from the ENV
+
+=item restore
+
+returns a hash for a given url
+
+=item querysend
+
+Tells client about the lonsql process that has been launched in response
+to a sent query.
+
+=item queryreply
+
+Accept information from lonsql and make appropriate storage in temporary
+file space.
+
+=item idput
+
+Defines usernames as corresponding to IDs. (These "IDs" are unique identifiers
+for each student, defined perhaps by the institutional Registrar.)
+
+=item idget
+
+Returns usernames corresponding to IDs. (These "IDs" are unique identifiers
+for each student, defined perhaps by the institutional Registrar.)
+
+=item tmpput
+
+Accept and store information in temporary space.
+
+=item tmpget
+
+Send along temporarily stored information.
+
+=item ls
+
+List part of a user's directory.
+
+=item Hanging up (exit or init)
+
+What to do when a client tells the server that they (the client)
+are leaving the network.
+
+=item unknown command
+
+If B is sent an unknown command (not in the list above),
+it replys to the client "unknown_cmd".
+
+=item UNKNOWN CLIENT
+
+If the anti-spoofing algorithm cannot verify the client,
+the client is rejected (with a "refused" message sent
+to the client, and the connection is closed.
+
+=back
=head1 PREREQUISITES
@@ -1403,7 +1752,3 @@ linux
Server/Process
=cut
-
-
-
-