--- loncom/auth/lonauth.pm	2003/04/07 18:24:05	1.48
+++ loncom/auth/lonauth.pm	2005/06/07 02:14:28	1.67
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # User Authentication Module
 #
-# $Id: lonauth.pm,v 1.48 2003/04/07 18:24:05 www Exp $
+# $Id: lonauth.pm,v 1.67 2005/06/07 02:14:28 www 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;
 
@@ -106,7 +100,15 @@ sub success {
     if (($userenv{'interface'}) && (!$FORM{'interface'})) {
 	$FORM{'interface'}=$userenv{'interface'};
     }
-    $ENV{'environment.remote'}=$userenv{'remote'};
+    $env{'environment.remote'}=$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
 
     {
@@ -126,16 +128,20 @@ 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 "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 $idf "request.role.adv=$env{'user.adv'}\n";
 	print $idf "request.host=$ENV{'REMOTE_ADDR'}\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') ||
@@ -147,9 +153,9 @@ sub success {
 	if ($userroles ne '') { print $idf "$userroles"; }
 	$idf->close();
     }
-    $ENV{'request.role'}='cm';
-    $ENV{'request.role.adv'}=$ENV{'user.adv'};
-    $ENV{'browser.type'}=$clientbrowser;
+    $env{'request.role'}='cm';
+    $env{'request.role.adv'}=$env{'user.adv'};
+    $env{'browser.type'}=$clientbrowser;
 # -------------------------------------------------------------------- Log this
 
     &Apache::lonnet::log($domain,$username,$authhost,
@@ -170,16 +176,29 @@ sub success {
 # -------------------------------------------------------- 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 $add=&addcontent();
+    my $continuelink;
+    if (($env{'browser.interface'} eq 'textual') ||
+        ($env{'environment.remote'} eq 'off')) {
+	$continuelink="<a href=\"$lowerurl\">".&mt('Continue')."</a>";
+    }
 # ------------------------------------------------- Output for successful login
 
     $r->send_cgi_header(<<ENDHEADER);
-Content-type: text/html
+Content-type: text/html$add
 Set-cookie: $cookie
 
 ENDHEADER
+    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>
@@ -189,12 +208,12 @@ $startupremote
 $bodytag
 $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
 $maincall
+$continuelink
 </body>
 </html>
 ENDSUCCESS
@@ -205,8 +224,9 @@ ENDSUCCESS
 sub failed {
     my ($r,$message) = @_;
     my $bodytag=&Apache::loncommon::bodytag('Unsuccessful Login');
+    my $add=&addcontent();
     $r->send_cgi_header(<<ENDFHEADER);
-Content-type: text/html
+Content-type: text/html$add
 
 ENDFHEADER
     $r->print(<<ENDFAILED);
@@ -214,7 +234,6 @@ ENDFHEADER
 <head>
 <title>Unsuccessful Login to the LearningOnline Network with CAPA</title>
 </head>
-<html>
 $bodytag
 <h1>Sorry ...</h1>
 <p><b>$message</b></p>
@@ -226,13 +245,90 @@ $bodytag
 ENDFAILED
 }
 
+# --------------------------------------------------------------------- Charset
+
+sub addcontent {
+    my $encoding=&Apache::lonlocal::current_encoding;
+    if ($encoding) {
+	return '; charset='.$encoding;
+    } else {
+	return '';
+    }
+}
+
+# ------------------------------------------------------------------ Rerouting!
+
+sub reroute {
+    my $r=shift;
+    my $bodytag=&Apache::loncommon::bodytag('Rerouting');
+    $r->send_cgi_header(<<ENDRFHEADER);
+Content-type: text/html
+
+ENDRFHEADER
+    $r->print(<<ENDRFAILED);
+<html>
+<head>
+<title>Rerouting Login to the LearningOnline Network with CAPA</title>
+</head>
+$bodytag
+<h1>Sorry ...</h1>
+Please <a href="/">log in again</a>.
+</body>
+</html>
+ENDRFAILED
+}
+
 # ---------------------------------------------------------------- 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
+	    $r->send_cgi_header(<<ENDFHEADER);
+Content-type: text/html
+
+ENDFHEADER
+	    my $bodytag=&Apache::loncommon::bodytag('Already logged in');
+	    $r->print(<<ENDFAILED);
+<html>
+<head>
+<title>Already logged in</title>
+</head>
+$bodytag
+<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>
+</body>
+</html>
+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;
@@ -244,11 +340,16 @@ 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');
@@ -280,14 +381,17 @@ 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'},
@@ -301,11 +405,33 @@ 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;
 }