--- loncom/auth/lonauth.pm	2003/03/17 13:41:12	1.46
+++ loncom/auth/lonauth.pm	2006/05/01 21:04:31	1.76
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # User Authentication Module
 #
-# $Id: lonauth.pm,v 1.46 2003/03/17 13:41:12 matthew Exp $
+# $Id: lonauth.pm,v 1.76 2006/05/01 21:04:31 albertel Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -25,13 +25,6 @@
 #
 # http://www.lon-capa.org/
 #
-# 5/21/99,5/22,5/25,5/26,5/27,5/29,6/2,6/11,6/14,6/15
-# 16/11,12/16,
-# 1/14,2/24,2/28,2/29,3/7,5/29,5/30,5/31,6/1,6/5,6/29,
-# 7/1,7/10,10/2,10/5,10/9,10/26,10/30,11/10,
-# 05/28,05/29 Gerd Kortemeyer
-# 07/28,08/03 Gerd Kortemeyer
-# 8/20 Gerd Kortemeyer
 
 package Apache::lonauth;
 
@@ -43,9 +36,10 @@ use CGI::Cookie();
 use DynaLoader; # for Crypt::DES version
 use Crypt::DES;
 use Apache::loncommon();
-use Apache::lonnet();
+use Apache::lonnet;
 use Apache::lonmenu();
 use Fcntl qw(:flock);
+use Apache::lonlocal;
 
 my %FORM;
 
@@ -55,27 +49,47 @@ sub success {
     my ($r, $username, $domain, $authhost,$lowerurl) = @_;
     my $lonids=$r->dir_config('lonIDsDir');
 
+    my $public=($username eq 'public' && $domain eq 'public');
+
 # See if old ID present, if so, remove
 
-    my $filename;
-    opendir(DIR,$lonids);
-    while ($filename=readdir(DIR)) {
-       if ($filename=~/^$username\_\d+\_$domain\_$authhost\.id$/) {
-	  unlink($lonids.'/'.$filename);
-       }
-    }
-    closedir(DIR);
+    my ($filename,$cookie,$userroles);
+    my $now=time;
 
-# Give them a new cookie
+    if ($public) {
+	my $max_public=100;
+	my $oldest;
+	my $oldest_time=0;
+	for(my $next=1;$next<=$max_public;$next++) {
+	    if (-e $lonids."/publicuser_$next.id") {
+		my $mtime=(stat($lonids."/publicuser_$next.id"))[9];
+		if ($mtime<$oldest_time || !$oldest_time) {
+		    $oldest_time=$mtime;
+		    $oldest=$next;
+		}
+	    } else {
+		$cookie="publicuser_$next";
+		last;
+	    }
+	}
+	if (!$cookie) { $cookie="publicuser_$oldest"; }
+    } else {
+	opendir(DIR,$lonids);
+	while ($filename=readdir(DIR)) {
+	    if ($filename=~/^$username\_\d+\_$domain\_$authhost\.id$/) {
+		unlink($lonids.'/'.$filename);
+	    }
+	}
+	closedir(DIR);
 
-    my $cookie;
-    my $now=time;
-    $cookie="$username\_$now\_$domain\_$authhost";
+# Give them a new cookie
 
+	$cookie="$username\_$now\_$domain\_$authhost";
+    
 # Initialize roles
 
-    my $userroles=Apache::lonnet::rolesinit($domain,$username,$authhost);
-
+	$userroles=Apache::lonnet::rolesinit($domain,$username,$authhost);
+    }
 # ------------------------------------ Check browser type and MathML capability
 
     my ($httpbrowser,$clientbrowser,$clientversion,$clientmathml,
@@ -99,6 +113,8 @@ sub success {
     my %userenv=Apache::lonnet::dump('environment',$domain,$username);
     my ($tmp) = keys(%userenv);
     if ($tmp !~ /^(con_lost|error|no_such_host)/i) {
+	# default remote control to off
+	if ($userenv{'remote'} ne 'on') { $userenv{'remote'} = 'off'; }
 	foreach my $key (keys(%userenv)) {
 	    $userenv.="environment.$key=$userenv{$key}\n";
 	}
@@ -106,6 +122,15 @@ sub success {
     if (($userenv{'interface'}) && (!$FORM{'interface'})) {
 	$FORM{'interface'}=$userenv{'interface'};
     }
+    $env{'environment.remote'}=$userenv{'remote'};
+    if ($userenv{'texengine'} eq 'ttm') { $clientmathml=1; }
+
+# --------------- Do not trust query string to be put directly into environment
+    foreach ('imagesuppress','appletsuppress',
+	     'embedsuppress','fontenhance','blackwhite',
+	     'interface','localpath','localres') {
+	$FORM{$_}=~s/[\n\r\=]//gs;
+    }
 # --------------------------------------------------------- Write first profile
 
     {
@@ -125,15 +150,24 @@ sub success {
 	print $idf "browser.mathml=$clientmathml\n";
 	print $idf "browser.unicode=$clientunicode\n";
 	print $idf "browser.os=$clientos\n";
+        if ($FORM{'localpath'}) {
+           print $idf "browser.localpath=$FORM{'localpath'}\n";
+           print $idf "browser.localres=$FORM{'localres'}\n";
+        }
+        print $idf "server.domain=".$r->dir_config('lonDefDomain')."\n";
 	print $idf "request.course.fn=\n";
 	print $idf "request.course.uri=\n";
 	print $idf "request.course.sec=\n";
 	print $idf "request.role=cm\n";
+        print $idf "request.role.adv=$env{'user.adv'}\n";
 	print $idf "request.host=$ENV{'REMOTE_ADDR'}\n";
+	if ($public) {
+	    print $idf "environment.remote=off\n";
+	}
 	if ($FORM{'interface'}) {
 	    $FORM{'interface'}=~s/\W//gs;
 	    print $idf "browser.interface=$FORM{'interface'}\n";
-	    $ENV{'browser.interface'}=$FORM{'interface'};
+	    $env{'browser.interface'}=$FORM{'interface'};
 	    foreach ('imagesuppress','appletsuppress',
 		     'embedsuppress','fontenhance','blackwhite') {
 		if (($FORM{$_} eq 'true') ||
@@ -145,8 +179,9 @@ sub success {
 	if ($userroles ne '') { print $idf "$userroles"; }
 	$idf->close();
     }
-    $ENV{'request.role'}='cm';
-    $ENV{'browser.type'}=$clientbrowser;
+    $env{'request.role'}='cm';
+    $env{'request.role.adv'}=$env{'user.adv'};
+    $env{'browser.type'}=$clientbrowser;
 # -------------------------------------------------------------------- Log this
 
     &Apache::lonnet::log($domain,$username,$authhost,
@@ -163,37 +198,48 @@ sub success {
 
 # ------------------------------------------------------------ Get cookie ready
 
+    if ($public or $lowerurl eq 'noredirect') { return $cookie; }
+
     $cookie="lonID=$cookie; path=/";
 # -------------------------------------------------------- Menu script and info
     my $windowinfo=&Apache::lonmenu::open($clientos);
     my $startupremote=&Apache::lonmenu::startupremote($lowerurl);
+    my $remoteinfo=&Apache::lonmenu::load_remote_msg($lowerurl);
     my $setflags=&Apache::lonmenu::setflags();
     my $maincall=&Apache::lonmenu::maincall();
-    my $bodytag=&Apache::loncommon::bodytag('Successful Login');
+    my $start_page=&Apache::loncommon::start_page('Successful Login',
+						  $startupremote,
+						  {'no_inline_link' => 1,});
+    my $end_page  =&Apache::loncommon::end_page();
+
+    my $continuelink;
+    if (($env{'browser.interface'} eq 'textual') ||
+        ($env{'environment.remote'} eq 'off')) {
+	$continuelink="<a href=\"$lowerurl\">".&mt('Continue')."</a>";
+    }
 # ------------------------------------------------- Output for successful login
 
-    $r->send_cgi_header(<<ENDHEADER);
-Content-type: text/html
-Set-cookie: $cookie
-
-ENDHEADER
+    &Apache::loncommon::content_type($r,'text/html');
+    $r->header_out('Set-cookie' => $cookie);
+    $r->send_http_header;
+
+    my %lt=&Apache::lonlocal::texthash(
+				       'wel' => 'Welcome',
+				       'mes' => 'Welcome to the Learning<i>Online</i> Network with CAPA. Please wait while your session is being set up',
+				       'pro' => 'Problems',
+				       'log' => 'loginproblems.html',
+				       );
     $r->print(<<ENDSUCCESS);
-<html>
-<head>
-<title>Successful Login to the LearningOnline Network with CAPA</title>
-$startupremote
-</head>
-$bodytag
+$start_page
 $setflags
 $windowinfo
-<h1>Welcome!</h1>
-Welcome to the Learning<i>Online</i> Network with CAPA.
-Please wait while your session
-is being set up.<p>
-<a href="/adm/loginproblems.html">Problems?</a></p>
+<h1>$lt{'wel'}</h1>
+$lt{'mes'}.<p>
+<a href="/adm/$lt{'log'}">$lt{'pro'}?</a></p>
+$remoteinfo
 $maincall
-</body>
-</html>
+$continuelink
+$end_page
 ENDSUCCESS
 }
 
@@ -201,35 +247,90 @@ ENDSUCCESS
 
 sub failed {
     my ($r,$message) = @_;
-    my $bodytag=&Apache::loncommon::bodytag('Unsuccessful Login');
-    $r->send_cgi_header(<<ENDFHEADER);
-Content-type: text/html
+    my $start_page = &Apache::loncommon::start_page('Unsuccessful Login',undef,
+						    {'no_inline_link' => 1,});
+    my $end_page   = &Apache::loncommon::end_page();
+
+    my %lt=('sorry'  => &mt('Sorry ...'),
+	    'please' => 
+	    &mt('Please [_1]log in again[_2].',
+		"<a href=\"/adm/login?username=$FORM{'uname'}&domain=$FORM{'udom'}\">",
+		'</a>'),
+	    'problemspage' => &mt('loginproblems.html'),
+	    'problems'     => 'Problems',
+	    );
+    &Apache::loncommon::content_type($r,'text/html');
+    $r->send_http_header;
 
-ENDFHEADER
     $r->print(<<ENDFAILED);
-<html>
-<head>
-<title>Unsuccessful Login to the LearningOnline Network with CAPA</title>
-</head>
-<html>
-$bodytag
-<h1>Sorry ...</h1>
+$start_page
+<h1>$lt{'sorry'}</h1>
 <p><b>$message</b></p>
-<p>Please <a href="/adm/login?username=$FORM{'uname'}&domain=$FORM{'udom'}">log in again</a>.</p>
+<p>$lt{'please'}</p>
 <p>
-<a href="/adm/loginproblems.html">Problems?</a></p>
-</body>
-</html>
+<a href="/adm/$lt{'problemspage'}">$lt{'problems'}</a></p>
+$end_page
 ENDFAILED
 }
 
+# ------------------------------------------------------------------ Rerouting!
+
+sub reroute {
+    my ($r) = @_;
+    &Apache::loncommon::content_type($r,'text/html');
+    $r->send_http_header;
+    my $msg='<h1>Sorry ...</h1>
+             Please <a href="/">log in again</a>.';
+    &Apache::loncommon::simple_error_page($r,'Rerouting',$msg);
+}
+
 # ---------------------------------------------------------------- Main handler
 
 sub handler {
     my $r = shift;
 
+# Are we re-routing?
+    if (-e '/home/httpd/html/lon-status/reroute.txt') {
+	&reroute($r);
+	return OK;
+    }
+
+    &Apache::lonlocal::get_language_handle($r);
+
+# -------------------------------- Prevent users from attempting to login twice
+    my %cookies=CGI::Cookie->parse($r->header_in('Cookie'));
+    my $lonid=$cookies{'lonID'};
+    my $cookie;
+    if ($lonid) {
+	my $handle=$lonid->value;
+        $handle=~s/\W//g;
+        my $lonidsdir=$r->dir_config('lonIDsDir');
+        if ((-e "$lonidsdir/$handle.id") && ($handle ne '')) {
+# Indeed, a valid token is found
+	    &Apache::loncommon::content_type($r,'text/html');
+	    $r->send_http_header;
+	    my $start_page = 
+		&Apache::loncommon::start_page('Already logged in');
+	    my $end_page = 
+		&Apache::loncommon::end_page();
+	    $r->print(<<ENDFAILED);
+$start_page
+<h1>You are already logged in</h1>
+<p>Please either <a href="/adm/roles">continue the current session</a> or
+<a href="/adm/logout">logout</a>.</p>
+<p>
+<a href="/adm/loginproblems.html">Problems?</a></p>
+$end_page
+ENDFAILED
+           return OK;
+	}
+    }
+
+# ---------------------------------------------------- No valid token, continue
+
+
     my $buffer;
-    $r->read($buffer,$r->header_in('Content-length'));
+    $r->read($buffer,$r->header_in('Content-length'),0);
     my @pairs=split(/&/,$buffer);
     my $pair; my $name; my $value;
     undef %FORM;
@@ -241,11 +342,16 @@ sub handler {
        $FORM{$name}=$value;
     } 
 
-    if ((!$FORM{'uname'}) || (!$FORM{'upass'}) || (!$FORM{'udom'})) {
+    if ((!$FORM{'uname'}) || (!$FORM{'upass0'}) || (!$FORM{'udom'})) {
 	failed($r,'Username, password and domain need to be specified.');
         return OK;
     }
+
+# split user logging in and "su"-user
+
+    ($FORM{'uname'},$FORM{'suname'})=split(/\:/,$FORM{'uname'});
     $FORM{'uname'} =~ s/\W//g;
+    $FORM{'suname'} =~ s/\W//g;
     $FORM{'udom'}  =~ s/\W//g;
 
     my $role   = $r->dir_config('lonRole');
@@ -277,14 +383,17 @@ sub handler {
     else {
 	$cipher=new DES $keybin;
     }
+    my $upass='';
+    for (my $i=0;$i<=2;$i++) {
+	my $chunk=
+	    $cipher->decrypt(unpack("a8",pack("H16",substr($FORM{'upass'.$i},0,16))));
 
-    my $upass=$cipher->decrypt(
-       unpack("a8",pack("H16",substr($FORM{'upass'},0,16))));
-
-    $upass.=$cipher->decrypt(
-       unpack("a8",pack("H16",substr($FORM{'upass'},16,16))));
+	$chunk.=
+	    $cipher->decrypt(unpack("a8",pack("H16",substr($FORM{'upass'.$i},16,16))));
 
-    $upass=substr($upass,1,ord(substr($upass,0,1)));
+	$chunk=substr($chunk,1,ord(substr($chunk,0,1)));
+	$upass.=$chunk;
+    }
 
 # ---------------------------------------------------------------- Authenticate
     my $authhost=Apache::lonnet::authenticate($FORM{'uname'},
@@ -298,11 +407,33 @@ sub handler {
         return OK;
     }
 
-    if (($firsturl eq '') || ($firsturl eq '/adm/logout')) {
+    if (($firsturl eq '') || 
+	($firsturl=~/^\/adm\/(logout|remote)/)) {
 	$firsturl='/adm/roles';
     }
-
-    success($r,$FORM{'uname'},$FORM{'udom'},$authhost,$firsturl);
+# --------------------------------- Are we attempting to login as somebody else?
+    if ($FORM{'suname'}) {
+# ------------ see if the original user has enough privileges to pull this stunt
+	if (&Apache::lonnet::privileged($FORM{'uname'},$FORM{'udom'})) {
+# ---------------------------------------------------- see if the su-user exists
+	    unless (&Apache::lonnet::homeserver($FORM{'suname'},$FORM{'udom'})
+		eq 'no_host') {
+		&Apache::lonnet::logthis(&Apache::lonnet::homeserver($FORM{'suname'},$FORM{'udom'}));
+# ------------------------------ see if the su-user is not too highly privileged
+		unless (&Apache::lonnet::privileged($FORM{'suname'},$FORM{'udom'})) {
+# -------------------------------------------------------- actually switch users
+		    &Apache::lonnet::logperm('User '.$FORM{'uname'}.' at '.$FORM{'udom'}.
+			' logging in as '.$FORM{'suname'});
+		    $FORM{'uname'}=$FORM{'suname'};
+		} else {
+		    &Apache::lonnet::logthis('Attempted switch user to privileged user');
+		}
+	    }
+	} else {
+	    &Apache::lonnet::logthis('Non-privileged user attempting switch user');
+	}
+    }
+    &success($r,$FORM{'uname'},$FORM{'udom'},$authhost,$firsturl);
     return OK;
 }