--- loncom/lond 2001/05/11 19:31:25 1.47
+++ loncom/lond 2003/03/14 21:25:44 1.103.2.1
@@ -1,6 +1,31 @@
#!/usr/bin/perl
# The LearningOnline Network
# lond "LON Daemon" Server (port "LOND" 5663)
+#
+# $Id: lond,v 1.103.2.1 2003/03/14 21:25:44 albertel Exp $
+#
+# Copyright Michigan State University Board of Trustees
+#
+# This file is part of the LearningOnline Network with CAPA (LON-CAPA).
+#
+# LON-CAPA is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# LON-CAPA is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with LON-CAPA; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+#
+# /home/httpd/html/adm/gpl.txt
+#
+# http://www.lon-capa.org/
+#
# 5/26/99,6/4,6/10,6/11,6/14,6/15,6/26,6/28,6/30,
# 7/8,7/9,7/10,7/12,7/17,7/19,9/21,
# 10/7,10/8,10/9,10/11,10/13,10/15,11/4,11/16,
@@ -10,19 +35,36 @@
# 06/29,06/30,07/14,07/15,07/17,07/20,07/25,09/18 Gerd Kortemeyer
# 12/05 Scott Harrison
# 12/05,12/13,12/29 Gerd Kortemeyer
+# YEAR=2001
# Jan 01 Scott Harrison
# 02/12 Gerd Kortemeyer
# 03/15 Scott Harrison
# 03/24 Gerd Kortemeyer
# 04/02 Scott Harrison
-# 05/11 Gerd Kortemeyer
-#
+# 05/11,05/28,08/30 Gerd Kortemeyer
+# 9/30,10/22,11/13,11/15,11/16 Scott Harrison
+# 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
+# 05/11 Scott Harrison
+###
+
# based on "Perl Cookbook" ISBN 1-56592-243-3
# preforker - server who forks first
# runs as a daemon
# HUPs
# uses IDEA encryption
+use lib '/home/httpd/lib/perl/';
+use LONCAPA::Configuration;
+
use IO::Socket;
use IO::File;
use Apache::File;
@@ -32,6 +74,76 @@ use Crypt::IDEA;
use LWP::UserAgent();
use GDBM_File;
use Authen::Krb4;
+use Authen::Krb5;
+use lib '/home/httpd/lib/perl/';
+use localauth;
+
+my $DEBUG = 0; # Non zero to enable debug log entries.
+
+my $status='';
+my $lastlog='';
+
+#
+# The array below are password error strings."
+#
+my $lastpwderror = 13; # Largest error number from lcpasswd.
+my @passwderrors = ("ok",
+ "lcpasswd must be run as user 'www'",
+ "lcpasswd got incorrect number of arguments",
+ "lcpasswd did not get the right nubmer of input text lines",
+ "lcpasswd too many simultaneous pwd changes in progress",
+ "lcpasswd User does not exist.",
+ "lcpasswd Incorrect current passwd",
+ "lcpasswd Unable to su to root.",
+ "lcpasswd Cannot set new passwd.",
+ "lcpasswd Username has invalid characters",
+ "lcpasswd Invalid characters in password",
+ "11", "12",
+ "lcpasswd Password mismatch");
+
+
+# The array below are lcuseradd error strings.:
+
+my $lastadderror = 13;
+my @adderrors = ("ok",
+ "User ID mismatch, lcuseradd must run as user www",
+ "lcuseradd Incorrect number of command line parameters must be 3",
+ "lcuseradd Incorrect number of stdinput lines, must be 3",
+ "lcuseradd Too many other simultaneous pwd changes in progress",
+ "lcuseradd User does not exist",
+ "lcuseradd Unabel to mak ewww member of users's group",
+ "lcuseradd Unable to su to root",
+ "lcuseradd Unable to set password",
+ "lcuseradd Usrname has invbalid charcters",
+ "lcuseradd Password has an invalid character",
+ "lcuseradd User already exists",
+ "lcuseradd Could not add user.",
+ "lcuseradd Password mismatch");
+
+
+#
+# Convert an error return code from lcpasswd to a string value.
+#
+sub lcpasswdstrerror {
+ my $ErrorCode = shift;
+ if(($ErrorCode < 0) || ($ErrorCode > $lastpwderror)) {
+ return "lcpasswd Unrecognized error return value ".$ErrorCode;
+ } else {
+ return $passwderrors[$ErrorCode];
+ }
+}
+
+#
+# Convert an error return code from lcuseradd to a string value:
+#
+sub lcuseraddstrerror {
+ my $ErrorCode = shift;
+ if(($ErrorCode < 0) || ($ErrorCode > $lastadderror)) {
+ return "lcuseradd - Unrecognized error code: ".$ErrorCode;
+ } else {
+ return $adderrors[$ErrorCode];
+ }
+}
# grabs exception and records it to log before exiting
sub catchexception {
@@ -41,27 +153,26 @@ sub catchexception {
&logthis("CRITICAL: "
."ABNORMAL EXIT. Child $$ for server $wasserver died through "
."a crash with this error msg->[$error]");
+ &logthis('Famous last words: '.$status.' - '.$lastlog);
if ($client) { print $client "error: $error\n"; }
+ $server->close();
die($error);
}
+sub timeout {
+ &logthis("CRITICAL: TIME OUT ".$$."");
+ &catchexception('Timeout');
+}
# -------------------------------- Set signal handlers to record abnormal exits
$SIG{'QUIT'}=\&catchexception;
$SIG{__DIE__}=\&catchexception;
-# ------------------------------------ Read httpd access.conf and get variables
-
-open (CONFIG,"/etc/httpd/conf/access.conf") || die "Can't read access.conf";
-
-while ($configline=) {
- if ($configline =~ /PerlSetVar/) {
- my ($dummy,$varname,$varvalue)=split(/\s+/,$configline);
- chomp($varvalue);
- $perlvar{$varname}=$varvalue;
- }
-}
-close(CONFIG);
+# ---------------------------------- Read loncapa_apache.conf and loncapa.conf
+&status("Read loncapa.conf and loncapa_apache.conf");
+my $perlvarref=LONCAPA::Configuration::read_conf('loncapa.conf');
+my %perlvar=%{$perlvarref};
+undef $perlvarref;
# ----------------------------- Make sure this process is running from user=www
my $wwwid=getpwnam('www');
@@ -92,7 +203,7 @@ open (CONFIG,"$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++;
@@ -111,7 +222,7 @@ $server = IO::Socket::INET->new(LocalPor
# global variables
-$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
@@ -119,14 +230,19 @@ $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 $pid died");
+ }
}
sub HUNTSMAN { # signal handler for SIGINT
local($SIG{CHLD}) = 'IGNORE'; # we're going to kill our children
kill 'INT' => keys %children;
+ &logthis("Free socket: ".shutdown($server,2)); # free up socket
my $execdir=$perlvar{'lonDaemons'};
unlink("$execdir/logs/lond.pid");
&logthis("CRITICAL: Shutting down");
@@ -136,13 +252,47 @@ sub HUNTSMAN { # si
sub HUPSMAN { # signal handler for SIGHUP
local($SIG{CHLD}) = 'IGNORE'; # we're going to kill our children
kill 'INT' => keys %children;
- close($server); # free up socket
+ &logthis("Free socket: ".shutdown($server,2)); # free up socket
&logthis("CRITICAL: Restarting");
unlink("$execdir/logs/lond.pid");
my $execdir=$perlvar{'lonDaemons'};
exec("$execdir/lond"); # here we go again
}
+sub checkchildren {
+ &initnewstatus();
+ &logstatus();
+ &logthis('Going to check on the children');
+ $docdir=$perlvar{'lonDocRoot'};
+ foreach (sort keys %children) {
+ sleep 1;
+ unless (kill 'USR1' => $_) {
+ &logthis ('Child '.$_.' is dead');
+ &logstatus($$.' is dead');
+ }
+ }
+ sleep 5;
+ $SIG{ALRM} = sub { die "timeout" };
+ $SIG{__DIE__} = 'DEFAULT';
+ foreach (sort keys %children) {
+ unless (-e "$docdir/lon-status/londchld/$_.txt") {
+ eval {
+ alarm(300);
+ &logthis('Child '.$_.' did not respond');
+ kill 9 => $_;
+ $emailto="$perlvar{'lonAdmEMail'},$perlvar{'lonSysEMail'}";
+ $subj="LON: $perlvar{'lonHostID'} killed lond process $_";
+ my $result=`echo 'Killed lond process $_.' | mailto $emailto -s '$subj' > /dev/null`;
+ $execdir=$perlvar{'lonDaemons'};
+ $result=`/bin/cp $execdir/logs/lond.log $execdir/logs/lond.log.$_`;
+ alarm(0);
+ }
+ }
+ }
+ $SIG{ALRM} = 'DEFAULT';
+ $SIG{__DIE__} = \&cathcexception;
+}
+
# --------------------------------------------------------------------- Logging
sub logthis {
@@ -151,9 +301,55 @@ sub logthis {
my $fh=IO::File->new(">>$execdir/logs/lond.log");
my $now=time;
my $local=localtime($now);
+ $lastlog=$local.': '.$message;
print $fh "$local ($$): $message\n";
}
+# ------------------------- Conditional log if $DEBUG true.
+sub Debug {
+ my $message = shift;
+ if($DEBUG) {
+ &logthis($message);
+ }
+}
+# ------------------------------------------------------------------ Log status
+
+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 {
+ my $docdir=$perlvar{'lonDocRoot'};
+ my $fh=IO::File->new(">$docdir/lon-status/londstatus.txt");
+ my $now=time;
+ my $local=localtime($now);
+ print $fh "LOND status $local - parent $$\n\n";
+ opendir(DIR,"$docdir/lon-status/londchld");
+ while ($filename=readdir(DIR)) {
+ unlink("$docdir/lon-status/londchld/$filename");
+ }
+ closedir(DIR);
+}
+
+# -------------------------------------------------------------- Status setting
+
+sub status {
+ my $what=shift;
+ my $now=time;
+ my $local=localtime($now);
+ $status=$local.': '.$what;
+ $0='lond: '.$what.' '.$local;
+}
# -------------------------------------------------------- Escape Special Chars
@@ -183,10 +379,10 @@ sub reconlonc {
if (kill 0 => $loncpid) {
&logthis("lonc at pid $loncpid responding, sending USR1");
kill USR1 => $loncpid;
- sleep 1;
+ sleep 5;
if (-e "$peerfile") { return; }
&logthis("$peerfile still not there, give it another try");
- sleep 5;
+ sleep 10;
if (-e "$peerfile") { return; }
&logthis(
"WARNING: $peerfile still not there, giving up");
@@ -224,6 +420,7 @@ sub reply {
if ($answer eq 'con_lost') {
$answer=subreply("ping",$server);
if ($answer ne $server) {
+ &logthis("sub reply: answer != server");
&reconlonc("$perlvar{'lonSockDir'}/$server");
}
$answer=subreply($cmd,$server);
@@ -300,6 +497,7 @@ open (PIDSAVE,">$execdir/logs/lond.pid")
print PIDSAVE "$$\n";
close(PIDSAVE);
&logthis("CRITICAL: ---------- Starting ----------");
+&status('Starting');
# ------------------------------------------------------- Now we are on our own
@@ -310,13 +508,19 @@ for (1 .. $PREFORK) {
# ----------------------------------------------------- Install signal handlers
+&status('Forked children');
+
$SIG{CHLD} = \&REAPER;
$SIG{INT} = $SIG{TERM} = \&HUNTSMAN;
$SIG{HUP} = \&HUPSMAN;
+$SIG{USR1} = \&checkchildren;
# And maintain the population.
while (1) {
+ &status('Sleeping');
sleep; # wait for a signal (i.e., child's death)
+ &logthis('Woke up');
+ &status('Woke up');
for ($i = $children; $i < $PREFORK; $i++) {
make_new_child(); # top up the child pool
}
@@ -340,38 +544,54 @@ sub make_new_child {
or die "Can't unblock SIGINT for fork: $!\n";
$children{$pid} = 1;
$children++;
+ &status('Started child '.$pid);
return;
} else {
# 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';
+
# unblock signals
sigprocmask(SIG_UNBLOCK, $sigset)
or die "Can't unblock SIGINT for fork: $!\n";
$tmpsnum=0;
-
+#---------------------------------------------------- kerberos 5 initialization
+ &Authen::Krb5::init_context();
+ &Authen::Krb5::init_ets();
+
# handle connections until we've reached $MAX_CLIENTS_PER_CHILD
for ($i=0; $i < $MAX_CLIENTS_PER_CHILD; $i++) {
+ &status('Idle, waiting for connection');
$client = $server->accept() or last;
-
+ &status('Accepted connection');
# =============================================================================
# do something with the connection
# -----------------------------------------------------------------------------
+ $client->sockopt(SO_KEEPALIVE, 1);# Enable monitoring of
+ # connection liveness.
# see if we know client and check for spoof IP by challenge
my $caller=getpeername($client);
my ($port,$iaddr)=unpack_sockaddr_in($caller);
my $clientip=inet_ntoa($iaddr);
my $clientrec=($hostid{$clientip} ne undef);
&logthis(
-"INFO: Connect from $clientip ($hostid{$clientip})");
+"INFO: Connection $i, $clientip ($hostid{$clientip})"
+ );
+ &status("Connecting $clientip ($hostid{$clientip})");
my $clientok;
if ($clientrec) {
+ &status("Waiting for init from $clientip ($hostid{$clientip})");
my $remotereq=<$client>;
$remotereq=~s/\W//g;
if ($remotereq eq 'init') {
my $challenge="$$".time;
print $client "$challenge\n";
+ &status(
+ "Waiting for challenge reply from $clientip ($hostid{$clientip})");
$remotereq=<$client>;
$remotereq=~s/\W//g;
if ($challenge eq $remotereq) {
@@ -380,28 +600,33 @@ sub make_new_child {
} else {
&logthis(
"WARNING: $clientip did not reply challenge");
- print $client "bye\n";
+ &status('No challenge reply '.$clientip);
}
} else {
&logthis(
"WARNING: "
."$clientip failed to initialize: >$remotereq< ");
- print $client "bye\n";
+ &status('No init '.$clientip);
}
} else {
&logthis(
"WARNING: Unknown client $clientip");
- print $client "bye\n";
+ &status('Hung up on '.$clientip);
}
if ($clientok) {
# ---------------- New known client connecting, could mean machine online again
+
&reconlonc("$perlvar{'lonSockDir'}/$hostid{$clientip}");
&logthis(
"Established connection: $hostid{$clientip}");
+ &status('Will listen to '.$hostid{$clientip});
# ------------------------------------------------------------ Process requests
while (my $userinput=<$client>) {
chomp($userinput);
+ Debug("Request = $userinput\n");
+ &status('Processing '.$hostid{$clientip}.': '.$userinput);
my $wasenc=0;
+ alarm(120);
# ------------------------------------------------------------ See if encrypted
if ($userinput =~ /^enc/) {
if ($cipher) {
@@ -415,8 +640,9 @@ sub make_new_child {
}
$userinput=substr($userinput,0,$cmdlength);
$wasenc=1;
- }
}
+ }
+
# ------------------------------------------------------------- Normal commands
# ------------------------------------------------------------------------ ping
if ($userinput =~ /^ping/) {
@@ -449,6 +675,20 @@ sub make_new_child {
$loadavg =~ s/\s.*//g;
my $loadpercent=100*$loadavg/$perlvar{'lonLoadLim'};
print $client "$loadpercent\n";
+# ----------------------------------------------------------------- currentauth
+ } elsif ($userinput =~ /^currentauth/) {
+ if ($wasenc==1) {
+ my ($cmd,$udom,$uname)=split(/:/,$userinput);
+ my $result = GetAuthType($udom, $uname);
+ if($result eq "nouser") {
+ print $client "unknown_user\n";
+ }
+ else {
+ print $client "$result\n"
+ }
+ } else {
+ print $client "refused\n";
+ }
# ------------------------------------------------------------------------ auth
} elsif ($userinput =~ /^auth/) {
if ($wasenc==1) {
@@ -464,18 +704,59 @@ sub make_new_child {
my ($howpwd,$contentpwd)=split(/:/,$realpasswd);
my $pwdcorrect=0;
if ($howpwd eq 'internal') {
+ &Debug("Internal auth");
$pwdcorrect=
(crypt($upass,$contentpwd) eq $contentpwd);
} elsif ($howpwd eq 'unix') {
- $contentpwd=(getpwnam($uname))[1];
- $pwdcorrect=
- (crypt($upass,$contentpwd) eq $contentpwd);
+ &Debug("Unix auth");
+ if((getpwnam($uname))[1] eq "") { #no such user!
+ $pwdcorrect = 0;
+ } else {
+ $contentpwd=(getpwnam($uname))[1];
+ 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;
+ $pwdcorrect=!$?;
+ }
+ }
} 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 'krb5') {
+ $null=pack("C",0);
+ unless ($upass=~/$null/) {
+ my $krbclient=&Authen::Krb5::parse_name($uname.'@'.$contentpwd);
+ my $krbservice="krbtgt/".$contentpwd."\@".$contentpwd;
+ my $krbserver=&Authen::Krb5::parse_name($krbservice);
+ my $credentials=&Authen::Krb5::cc_default();
+ $credentials->initialize($krbclient);
+ my $krbreturn =
+ &Authen::Krb5::get_in_tkt_with_password(
+ $krbclient,$krbserver,$upass,$credentials);
+# unless ($krbreturn) {
+# &logthis("Krb5 Error: ".
+# &Authen::Krb5::error());
+# }
+ $pwdcorrect = ($krbreturn == 1);
+ } else { $pwdcorrect=0; }
+ } elsif ($howpwd eq 'localauth') {
+ $pwdcorrect=&localauth::localauth($uname,$upass,
+ $contentpwd);
+ }
if ($pwdcorrect) {
print $client "authorized\n";
} else {
@@ -495,7 +776,8 @@ sub make_new_child {
chomp($npass);
$upass=&unescape($upass);
$npass=&unescape($npass);
- my $proname=propath($udom,$uname);
+ &Debug("Trying to change password for $uname");
+ my $proname=propath($udom,$uname);
my $passfilename="$proname/passwd";
if (-e $passfilename) {
my $realpasswd;
@@ -504,17 +786,54 @@ sub make_new_child {
chomp($realpasswd);
my ($howpwd,$contentpwd)=split(/:/,$realpasswd);
if ($howpwd eq 'internal') {
+ &Debug("internal auth");
if (crypt($upass,$contentpwd) eq $contentpwd) {
my $salt=time;
$salt=substr($salt,6,2);
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
+ &Debug("auth is unix");
+ $contentpwd=(getpwnam($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;
+ &Debug("exited pwauth with $? ($uname,$upass) ");
+ $pwdcorrect=($? == 0);
+ }
+ if ($pwdcorrect) {
+ my $execdir=$perlvar{'lonDaemons'};
+ &Debug("Opening lcpasswd pipeline");
+ my $pf = IO::File->new("|$execdir/lcpasswd > /home/www/lcpasswd.log");
+ print $pf "$uname\n$npass\n$npass\n";
+ close $pf;
+ my $err = $?;
+ my $result = ($err>0 ? 'pwchange_failure'
+ : 'ok');
+ &logthis("Result of password change for $uname: ".
+ &lcpasswdstrerror($?));
+ print $client "$result\n";
+ } else {
+ print $client "non_authorized\n";
+ }
+ } else {
print $client "auth_mode_error\n";
}
} else {
@@ -525,13 +844,19 @@ sub make_new_child {
}
# -------------------------------------------------------------------- makeuser
} elsif ($userinput =~ /^makeuser/) {
+ &Debug("Make user received");
+ my $oldumask=umask(0077);
if ($wasenc==1) {
my
($cmd,$udom,$uname,$umode,$npass)=split(/:/,$userinput);
+ &Debug("cmd =".$cmd." $udom =".$udom.
+ " uname=".$uname);
chomp($npass);
$npass=&unescape($npass);
my $proname=propath($udom,$uname);
my $passfilename="$proname/passwd";
+ &Debug("Password file created will be:".
+ $passfilename);
if (-e $passfilename) {
print $client "already_exists\n";
} elsif ($udom ne $perlvar{'lonDefDomain'}) {
@@ -544,35 +869,14 @@ sub make_new_child {
$fpnow.='/'.$fpparts[$i];
unless (-e $fpnow) {
unless (mkdir($fpnow,0777)) {
- $fperror="error:$!\n";
+ $fperror="error:$!";
}
}
}
unless ($fperror) {
- if ($umode eq 'krb4') {
- {
- my $pf = IO::File->new(">$passfilename");
- print $pf "krb4:$npass\n";
- }
- print $client "ok\n";
- } elsif ($umode eq 'internal') {
- my $salt=time;
- $salt=substr($salt,6,2);
- my $ncpass=crypt($npass,$salt);
- {
- my $pf = IO::File->new(">$passfilename");
- print $pf "internal:$ncpass\n";
- }
- print $client "ok\n";
- } elsif ($umode eq 'none') {
- {
- my $pf = IO::File->new(">$passfilename");
- print $pf "none:\n";
- }
- print $client "ok\n";
- } else {
- print $client "auth_mode_error\n";
- }
+ my $result=&make_passwd_file($uname, $umode,$npass,
+ $passfilename);
+ print $client $result;
} else {
print $client "$fperror\n";
}
@@ -580,6 +884,29 @@ sub make_new_child {
} else {
print $client "refused\n";
}
+ umask($oldumask);
+# -------------------------------------------------------------- changeuserauth
+ } elsif ($userinput =~ /^changeuserauth/) {
+ &Debug("Changing authorization");
+ if ($wasenc==1) {
+ my
+ ($cmd,$udom,$uname,$umode,$npass)=split(/:/,$userinput);
+ chomp($npass);
+ &Debug("cmd = ".$cmd." domain= ".$udom.
+ "uname =".$uname." umode= ".$umode);
+ $npass=&unescape($npass);
+ my $proname=&propath($udom,$uname);
+ my $passfilename="$proname/passwd";
+ if ($udom ne $perlvar{'lonDefDomain'}) {
+ print $client "not_right_domain\n";
+ } else {
+ my $result=&make_passwd_file($uname, $umode,$npass,
+ $passfilename);
+ print $client $result;
+ }
+ } else {
+ print $client "refused\n";
+ }
# ------------------------------------------------------------------------ home
} elsif ($userinput =~ /^home/) {
my ($cmd,$udom,$uname)=split(/:/,$userinput);
@@ -642,48 +969,65 @@ sub make_new_child {
} else {
print $client "rejected\n";
}
+# -------------------------------------- fetch a user file from a remote server
+ } elsif ($userinput =~ /^fetchuserfile/) {
+ my ($cmd,$fname)=split(/:/,$userinput);
+ my ($udom,$uname,$ufile)=split(/\//,$fname);
+ my $udir=propath($udom,$uname).'/userfiles';
+ unless (-e $udir) { mkdir($udir,0770); }
+ if (-e $udir) {
+ $ufile=~s/^[\.\~]+//;
+ $ufile=~s/\///g;
+ my $transname=$udir.'/'.$ufile;
+ my $remoteurl='http://'.$clientip.'/userfiles/'.$fname;
+ my $response;
+ {
+ my $ua=new LWP::UserAgent;
+ my $request=new HTTP::Request('GET',"$remoteurl");
+ $response=$ua->request($request,$transname);
+ }
+ if ($response->is_error()) {
+ unlink($transname);
+ my $message=$response->status_line;
+ &logthis(
+ "LWP GET: $message for $fname ($remoteurl)");
+ print $client "failed\n";
+ } else {
+ print $client "ok\n";
+ }
+ } else {
+ print $client "not_home\n";
+ }
+# ------------------------------------------ authenticate access to a user file
+ } elsif ($userinput =~ /^tokenauthuserfile/) {
+ my ($cmd,$fname,$session)=split(/:/,$userinput);
+ chomp($session);
+ $reply='non_auth';
+ if (open(ENVIN,$perlvar{'lonIDsDir'}.'/'.
+ $session.'.id')) {
+ while ($line=) {
+ if ($line=~/userfile\.$fname\=/) { $reply='ok'; }
+ }
+ close(ENVIN);
+ print $client $reply."\n";
+ } else {
+ print $client "invalid_token\n";
+ }
# ----------------------------------------------------------------- unsubscribe
} elsif ($userinput =~ /^unsub/) {
my ($cmd,$fname)=split(/:/,$userinput);
if (-e $fname) {
- if (unlink("$fname.$hostid{$clientip}")) {
- print $client "ok\n";
- } else {
- print $client "not_subscribed\n";
- }
+ print $client &unsub($client,$fname,$clientip);
} else {
print $client "not_found\n";
}
# ------------------------------------------------------------------- subscribe
} elsif ($userinput =~ /^sub/) {
+ print $client &subscribe($userinput,$clientip);
+# ------------------------------------------------------------- current version
+ } elsif ($userinput =~ /^currentversion/) {
my ($cmd,$fname)=split(/:/,$userinput);
- my $ownership=ishome($fname);
- if ($ownership eq 'owner') {
- if (-e $fname) {
- if (-d $fname) {
- print $client "directory\n";
- } else {
- $now=time;
- {
- my $sh;
- if ($sh=
- IO::File->new(">$fname.$hostid{$clientip}")) {
- print $sh "$clientip:$now\n";
- }
- }
- unless ($fname=~/\.meta$/) {
- unlink("$fname.meta.$hostid{$clientip}");
- }
- $fname=~s/\/home\/httpd\/html\/res/raw/;
- $fname="http://$thisserver/".$fname;
- print $client "$fname\n";
- }
- } else {
- print $client "not_found\n";
- }
- } else {
- print $client "rejected\n";
- }
+ print $client ¤tversion($fname)."\n";
# ------------------------------------------------------------------------- log
} elsif ($userinput =~ /^log/) {
my ($cmd,$udom,$uname,$what)=split(/:/,$userinput);
@@ -709,7 +1053,7 @@ sub make_new_child {
chomp($what);
my $proname=propath($udom,$uname);
my $now=time;
- {
+ unless ($namespace=~/^nohist\_/) {
my $hfh;
if (
$hfh=IO::File->new(">>$proname/$namespace.hist")
@@ -734,9 +1078,13 @@ sub make_new_child {
}
# -------------------------------------------------------------------- rolesput
} elsif ($userinput =~ /^rolesput/) {
+ &Debug("rolesput");
if ($wasenc==1) {
my ($cmd,$exedom,$exeuser,$udom,$uname,$what)
=split(/:/,$userinput);
+ &Debug("cmd = ".$cmd." exedom= ".$exedom.
+ "user = ".$exeuser." udom=".$udom.
+ "what = ".$what);
my $namespace='roles';
chomp($what);
my $proname=propath($udom,$uname);
@@ -753,7 +1101,11 @@ sub make_new_child {
if (tie(%hash,'GDBM_File',"$proname/$namespace.db",&GDBM_WRCREAT,0640)) {
foreach $pair (@pairs) {
($key,$value)=split(/=/,$pair);
+ &ManagePermissions($key, $udom, $uname,
+ &GetAuthType( $udom,
+ $uname));
$hash{$key}=$value;
+
}
if (untie(%hash)) {
print $client "ok\n";
@@ -834,7 +1186,7 @@ sub make_new_child {
chomp($what);
my $proname=propath($udom,$uname);
my $now=time;
- {
+ unless ($namespace=~/^nohist\_/) {
my $hfh;
if (
$hfh=IO::File->new(">>$proname/$namespace.hist")
@@ -876,21 +1228,34 @@ sub make_new_child {
}
# ------------------------------------------------------------------------ dump
} elsif ($userinput =~ /^dump/) {
- my ($cmd,$udom,$uname,$namespace)
+ my ($cmd,$udom,$uname,$namespace,$regexp)
=split(/:/,$userinput);
$namespace=~s/\//\_/g;
$namespace=~s/\W//g;
- my $proname=propath($udom,$uname);
+ if (defined($regexp)) {
+ $regexp=&unescape($regexp);
+ } else {
+ $regexp='.';
+ }
my $qresult='';
- if (tie(%hash,'GDBM_File',"$proname/$namespace.db",&GDBM_READER,0640)) {
- foreach $key (keys %hash) {
- $qresult.="$key=$hash{$key}&";
+ my $proname=propath($udom,$uname);
+ if (tie(%hash,'GDBM_File',"$proname/$namespace.db",&GDBM_READER(),0640)) {
+ study($regexp);
+ while (($key,$value) = each(%hash)) {
+ if ($regexp eq '.') {
+ $qresult.=$key.'='.$value.'&';
+ } else {
+ my $unescapeKey = &unescape($key);
+ if (eval('$unescapeKey=~/$regexp/')) {
+ $qresult.="$key=$value&";
+ }
+ }
}
- if (untie(%hash)) {
- $qresult=~s/\&$//;
- print $client "$qresult\n";
+ if (untie(%hash)) {
+ chop($qresult);
+ print $client "$qresult\n";
} else {
- print $client "error:$!\n";
+ print $client "error:$!\n";
}
} else {
print $client "error:$!\n";
@@ -905,7 +1270,7 @@ sub make_new_child {
chomp($what);
my $proname=propath($udom,$uname);
my $now=time;
- {
+ unless ($namespace=~/^nohist\_/) {
my $hfh;
if (
$hfh=IO::File->new(">>$proname/$namespace.hist")
@@ -969,20 +1334,28 @@ sub make_new_child {
} else {
print $client "error:$!\n";
}
+# -------------------------------------------------------------------- chatsend
+ } elsif ($userinput =~ /^chatsend/) {
+ my ($cmd,$cdom,$cnum,$newpost)=split(/\:/,$userinput);
+ &chatadd($cdom,$cnum,$newpost);
+ print $client "ok\n";
+# -------------------------------------------------------------------- chatretr
+ } elsif ($userinput =~ /^chatretr/) {
+ my ($cmd,$cdom,$cnum)=split(/\:/,$userinput);
+ my $reply='';
+ foreach (&getchat($cdom,$cnum)) {
+ $reply.=&escape($_).':';
+ }
+ $reply=~s/\:$//;
+ print $client $reply."\n";
# ------------------------------------------------------------------- querysend
} elsif ($userinput =~ /^querysend/) {
my ($cmd,$query,
- $custom,$customshow)=split(/:/,$userinput);
+ $arg1,$arg2,$arg3)=split(/\:/,$userinput);
$query=~s/\n*$//g;
- unless ($custom or $customshow) {
- print $client "".
- sqlreply("$hostid{$clientip}\&$query")."\n";
- }
- else {
- print $client "".
+ print $client "".
sqlreply("$hostid{$clientip}\&$query".
- "\&$custom"."\&$customshow")."\n";
- }
+ "\&$arg1"."\&$arg2"."\&$arg3")."\n";
# ------------------------------------------------------------------ queryreply
} elsif ($userinput =~ /^queryreply/) {
my ($cmd,$id,$reply)=split(/:/,$userinput);
@@ -1088,37 +1461,58 @@ sub make_new_child {
my $ulsout='';
my $ulsfn;
if (-e $ulsdir) {
- if (opendir(LSDIR,$ulsdir)) {
- while ($ulsfn=readdir(LSDIR)) {
- my @ulsstats=stat($ulsdir.'/'.$ulsfn);
- $ulsout.=$ulsfn.'&'.join('&',@ulsstats).':';
- }
- closedir(LSDIR);
- }
- } else {
+ if(-d $ulsdir) {
+ if (opendir(LSDIR,$ulsdir)) {
+ while ($ulsfn=readdir(LSDIR)) {
+ my @ulsstats=stat($ulsdir.'/'.$ulsfn);
+ $ulsout.=$ulsfn.'&'.
+ join('&',@ulsstats).':';
+ }
+ closedir(LSDIR);
+ }
+ } else {
+ my @ulsstats=stat($ulsdir);
+ $ulsout.=$ulsfn.'&'.join('&',@ulsstats).':';
+ }
+ } else {
$ulsout='no_such_dir';
}
if ($ulsout eq '') { $ulsout='empty'; }
print $client "$ulsout\n";
+# ------------------------------------------------------------------ Hanging up
+ } elsif (($userinput =~ /^exit/) ||
+ ($userinput =~ /^init/)) {
+ &logthis(
+ "Client $clientip ($hostid{$clientip}) hanging up: $userinput");
+ print $client "bye\n";
+ $client->close();
+ last;
# ------------------------------------------------------------- unknown command
} else {
# unknown command
print $client "unknown_cmd\n";
}
-# ------------------------------------------------------ client unknown, refuse
+# -------------------------------------------------------------------- complete
+ alarm(0);
+ &status('Listening to '.$hostid{$clientip});
}
+# --------------------------------------------- client unknown or fishy, refuse
} else {
print $client "refused\n";
+ $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
+ $server->close();
+
# this exit is VERY important, otherwise the child will become
# a producer of more and more children, forking yourself into
# process death.
@@ -1127,6 +1521,592 @@ sub make_new_child {
}
+#
+# Checks to see if the input roleput request was to set
+# an author role. If so, invokes the lchtmldir script to set
+# up a correct public_html
+# Parameters:
+# request - The request sent to the rolesput subchunk.
+# We're looking for /domain/_au
+# domain - The domain in which the user is having roles doctored.
+# user - Name of the user for which the role is being put.
+# authtype - The authentication type associated with the user.
+#
+sub ManagePermissions
+{
+ my $request = shift;
+ my $domain = shift;
+ my $user = shift;
+ my $authtype= shift;
+
+ # See if the request is of the form /$domain/_au
+
+ if($request =~ /^(\/$domain\/_au)$/) { # It's an author rolesput...
+ my $execdir = $perlvar{'lonDaemons'};
+ my $userhome= "/home/$user" ;
+ Debug("system $execdir/lchtmldir $userhome $system $authtype");
+ system("$execdir/lchtmldir $userhome $user $authtype");
+ }
+}
+#
+# GetAuthType - Determines the authorization type of a user in a domain.
+
+# Returns the authorization type or nouser if there is no such user.
+#
+sub GetAuthType
+{
+ my $domain = shift;
+ my $user = shift;
+
+ Debug("GetAuthType( $domain, $user ) \n");
+ my $proname = &propath($domain, $user);
+ my $passwdfile = "$proname/passwd";
+ if( -e $passwdfile ) {
+ my $pf = IO::File->new($passwdfile);
+ my $realpassword = <$pf>;
+ chomp($realpassword);
+ Debug("Password info = $realpassword\n");
+ my ($authtype, $contentpwd) = split(/:/, $realpassword);
+ Debug("Authtype = $authtype, content = $contentpwd\n");
+ my $availinfo = '';
+ if($authtype eq 'krb4' or $authtype eq 'krb5') {
+ $availinfo = $contentpwd;
+ }
+
+ return "$authtype:$availinfo";
+ }
+ else {
+ Debug("Returning nouser");
+ return "nouser";
+ }
+}
+
+sub addline {
+ my ($fname,$hostid,$ip,$newline)=@_;
+ my $contents;
+ my $found=0;
+ my $expr='^'.$hostid.':'.$ip.':';
+ $expr =~ s/\./\\\./g;
+ if ($sh=IO::File->new("$fname.subscription")) {
+ while (my $subline=<$sh>) {
+ if ($subline !~ /$expr/) {$contents.= $subline;} else {$found=1;}
+ }
+ $sh->close();
+ }
+ $sh=IO::File->new(">$fname.subscription");
+ if ($contents) { print $sh $contents; }
+ if ($newline) { print $sh $newline; }
+ $sh->close();
+ return $found;
+}
+
+sub getchat {
+ my ($cdom,$cname)=@_;
+ my %hash;
+ my $proname=&propath($cdom,$cname);
+ my @entries=();
+ if (tie(%hash,'GDBM_File',"$proname/nohist_chatroom.db",
+ &GDBM_READER(),0640)) {
+ @entries=map { $_.':'.$hash{$_} } sort keys %hash;
+ untie %hash;
+ }
+ return @entries;
+}
+
+sub chatadd {
+ my ($cdom,$cname,$newchat)=@_;
+ my %hash;
+ my $proname=&propath($cdom,$cname);
+ my @entries=();
+ if (tie(%hash,'GDBM_File',"$proname/nohist_chatroom.db",
+ &GDBM_WRCREAT(),0640)) {
+ @entries=map { $_.':'.$hash{$_} } sort keys %hash;
+ my $time=time;
+ my ($lastid)=($entries[$#entries]=~/^(\w+)\:/);
+ my ($thentime,$idnum)=split(/\_/,$lastid);
+ my $newid=$time.'_000000';
+ if ($thentime==$time) {
+ $idnum=~s/^0+//;
+ $idnum++;
+ $idnum=substr('000000'.$idnum,-6,6);
+ $newid=$time.'_'.$idnum;
+ }
+ $hash{$newid}=$newchat;
+ my $expired=$time-3600;
+ foreach (keys %hash) {
+ my ($thistime)=($_=~/(\d+)\_/);
+ if ($thistime<$expired) {
+ delete $hash{$_};
+ }
+ }
+ untie %hash;
+ }
+}
+
+sub unsub {
+ my ($fname,$clientip)=@_;
+ my $result;
+ if (unlink("$fname.$hostid{$clientip}")) {
+ $result="ok\n";
+ } else {
+ $result="not_subscribed\n";
+ }
+ if (-e "$fname.subscription") {
+ my $found=&addline($fname,$hostid{$clientip},$clientip,'');
+ if ($found) { $result="ok\n"; }
+ } else {
+ if ($result != "ok\n") { $result="not_subscribed\n"; }
+ }
+ return $result;
+}
+
+sub currentversion {
+ my $fname=shift;
+ my $version=-1;
+ my $ulsdir='';
+ if ($fname=~/^(.+)\/[^\/]+$/) {
+ $ulsdir=$1;
+ }
+ $fname=~s/\.\d+\.(\w+(?:\.meta)*)$/\.$1/;
+ $fname=~s/\.(\w+(?:\.meta)*)$/\.\(\\d\+\)\.$1\$/;
+
+ if (-e $fname) { $version=1; }
+ if (-e $ulsdir) {
+ if(-d $ulsdir) {
+ if (opendir(LSDIR,$ulsdir)) {
+ while ($ulsfn=readdir(LSDIR)) {
+# see if this is a regular file (ignore links produced earlier)
+ my $thisfile=$ulsdir.'/'.$ulsfn;
+ unless (-l $thisfile) {
+ if ($thisfile=~/$fname/) {
+ if ($1>$version) { $version=$1; }
+ }
+ }
+ }
+ closedir(LSDIR);
+ $version++;
+ }
+ }
+ }
+ return $version;
+}
+
+sub thisversion {
+ my $fname=shift;
+ my $version=-1;
+ if ($fname=~/\.(\d+)\.\w+(?:\.meta)*$/) {
+ $version=$1;
+ }
+ return $version;
+}
+
+sub subscribe {
+ my ($userinput,$clientip)=@_;
+ my $result;
+ my ($cmd,$fname)=split(/:/,$userinput);
+ my $ownership=&ishome($fname);
+ if ($ownership eq 'owner') {
+# explitly asking for the current version?
+ unless (-e $fname) {
+ my $currentversion=¤tversion($fname);
+ if (&thisversion($fname)==$currentversion) {
+ if ($fname=~/^(.+)\.\d+\.(\w+(?:\.meta)*)$/) {
+ my $root=$1;
+ my $extension=$2;
+ symlink($root.'.'.$extension,
+ $root.'.'.$currentversion.'.'.$extension);
+ unless ($extension=~/\.meta$/) {
+ symlink($root.'.'.$extension.'.meta',
+ $root.'.'.$currentversion.'.'.$extension.'.meta');
+ }
+ }
+ }
+ }
+ if (-e $fname) {
+ if (-d $fname) {
+ $result="directory\n";
+ } else {
+ if (-e "$fname.$hostid{$clientip}") {&unsub($fname,$clientip);}
+ $now=time;
+ my $found=&addline($fname,$hostid{$clientip},$clientip,
+ "$hostid{$clientip}:$clientip:$now\n");
+ if ($found) { $result="$fname\n"; }
+ # if they were subscribed to only meta data, delete that
+ # subscription, when you subscribe to a file you also get
+ # the metadata
+ unless ($fname=~/\.meta$/) { &unsub("$fname.meta",$clientip); }
+ $fname=~s/\/home\/httpd\/html\/res/raw/;
+ $fname="http://$thisserver/".$fname;
+ $result="$fname\n";
+ }
+ } else {
+ $result="not_found\n";
+ }
+ } else {
+ $result="rejected\n";
+ }
+ return $result;
+}
+
+sub make_passwd_file {
+ my ($uname, $umode,$npass,$passfilename)=@_;
+ my $result="ok\n";
+ if ($umode eq 'krb4' or $umode eq 'krb5') {
+ {
+ my $pf = IO::File->new(">$passfilename");
+ print $pf "$umode:$npass\n";
+ }
+ } elsif ($umode eq 'internal') {
+ my $salt=time;
+ $salt=substr($salt,6,2);
+ my $ncpass=crypt($npass,$salt);
+ {
+ &Debug("Creating internal auth");
+ my $pf = IO::File->new(">$passfilename");
+ print $pf "internal:$ncpass\n";
+ }
+ } elsif ($umode eq 'localauth') {
+ {
+ my $pf = IO::File->new(">$passfilename");
+ print $pf "localauth:$npass\n";
+ }
+ } elsif ($umode eq 'unix') {
+ {
+ my $execpath="$perlvar{'lonDaemons'}/"."lcuseradd";
+ {
+ &Debug("Executing external: ".$execpath);
+ &Debug("user = ".$uname.", Password =". $npass);
+ my $se = IO::File->new("|$execpath > /home/www/lcuseradd.log");
+ print $se "$uname\n";
+ print $se "$npass\n";
+ print $se "$npass\n";
+ }
+ my $useraddok = $?;
+ if($useraddok > 0) {
+ &logthis("Failed lcuseradd: ".&lcuseraddstrerror($useraddok));
+ }
+ my $pf = IO::File->new(">$passfilename");
+ print $pf "unix:\n";
+ }
+ } elsif ($umode eq 'none') {
+ {
+ my $pf = IO::File->new(">$passfilename");
+ print $pf "none:\n";
+ }
+ } else {
+ $result="auth_mode_error\n";
+ }
+ return $result;
+}
+
+# ----------------------------------- POD (plain old documentation, CPAN style)
+
+=head1 NAME
+
+lond - "LON Daemon" Server (port "LOND" 5663)
+
+=head1 SYNOPSIS
+
+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
+
+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
+
+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
+
+IO::Socket
+IO::File
+Apache::File
+Symbol
+POSIX
+Crypt::IDEA
+LWP::UserAgent()
+GDBM_File
+Authen::Krb4
+Authen::Krb5
+
+=head1 COREQUISITES
+
+=head1 OSNAMES
+
+linux
+=head1 SCRIPT CATEGORIES
+Server/Process
+=cut