--- loncom/auth/loncacc.pm	1999/10/13 17:48:52	1.1.1.1
+++ loncom/auth/loncacc.pm	2006/11/27 16:47:16	1.43
@@ -1,51 +1,171 @@
 # The LearningOnline Network
 # Cookie Based Access Handler for Construction Area
 # (lonacc: 5/21/99,5/22,5/29,5/31 Gerd Kortemeyer)
-# 6/15 Gerd Kortemeyer
+#
+# $Id: loncacc.pm,v 1.43 2006/11/27 16:47:16 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/
+#
 
 package Apache::loncacc;
 
 use strict;
-use Apache::Constants qw(:common :http);
+use Apache::Constants qw(:common :http :methods REDIRECT);
 use CGI::Cookie();
+use Fcntl qw(:flock);
+use Apache::lonlocal;
+use Apache::lonnet;
+use Apache::lonacc;
+use LONCAPA qw(:DEFAULT :match);
+
+sub constructaccess {
+    my ($url,$ownerdomain)=@_;
+    my ($ownername)=($url=~/\/(?:\~|priv\/|home\/)($match_username)\//);
+    unless (($ownername) && ($ownerdomain)) { return ''; }
+    # We do not allow editing of previous versions of files.
+    if ($url=~/\.(\d+)\.(\w+)$/) { return ''; }
+    my @possibledomains = &Apache::lonnet::current_machine_domains();
+    if ($ownername eq $env{'user.name'}) {
+	foreach my $domain (@possibledomains) {
+	    if ($domain eq $env{'user.domain'}) {
+		return ($ownername,$domain);
+	    }
+	}
+    }
+    
+    foreach my $domain (@possibledomains) {
+	if (exists($env{'user.priv.ca./'.$domain.'/'.$ownername.'./'}) ||
+	    exists($env{'user.priv.aa./'.$domain.'/'.$ownername.'./'}) ) {
+	    return ($ownername,$domain);
+	}
+    }
+    return '';
+}
 
 sub handler {
     my $r = shift;
     my $requrl=$r->uri;
+    $env{'request.editurl'}=$requrl;
     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 $handle=&LONCAPA::clean_handle($lonid->value);
         my $lonidsdir=$r->dir_config('lonIDsDir');
         if ((-e "$lonidsdir/$handle.id") && ($handle ne '')) {
-            my $ownername=$requrl;
-            $ownername=~s/\/\~(\w+).*/\1/;
-            my $ownerdomain=$r->dir_config('lonDefDomain');
-            my @handleparts=split(/\_/,$handle);
-            my $username=$handleparts[0];
-            my $domain=$handleparts[2];
-            if (($username ne $ownername) || ($domain ne $ownerdomain)) {
-                $r->log_reason
-                   ("$username at $domain not authorized", $r->filename); 
+
+# ------------------------------------------------------ Initialize Environment
+
+            &Apache::lonnet::transfer_profile_to_env($lonidsdir,$handle);
+
+# --------------------------------------------------------- Initialize Language
+ 
+ 	    &Apache::lonlocal::get_language_handle($r);
+
+# -------------------------------------------------------------- Resource State
+
+            $env{'request.state'}    = "construct";
+            $env{'request.filename'} = $r->filename;
+
+            unless (&constructaccess($requrl,$r->dir_config('lonDefDomain'))) {
+                $r->log_reason("Unauthorized $requrl", $r->filename); 
 	        return HTTP_NOT_ACCEPTABLE;
             }
+
+# -------------------------------------------------------- Load POST parameters
+
+	    &Apache::lonacc::get_posted_cgi($r);
+
             return OK; 
         } else { 
             $r->log_reason("Cookie $handle not valid", $r->filename) 
         };
     }
-    $cookie=CGI::Cookie->new(-name  => 'lonURL',
-                             -value => $requrl, 
-                             -path  => '/');
-    $r->err_headers_out->add('Set-Cookie' => $cookie);
+
+# ----------------------------------------------- Store where they wanted to go
+
+    $env{'request.firsturl'}=$requrl;
     return FORBIDDEN;
 }
 
 1;
 __END__
 
+=head1 NAME
+
+Apache::lonacc - Cookie Based Access Handler for Construction Area
+
+=head1 SYNOPSIS
+
+Invoked (for various locations) by /etc/httpd/conf/loncapa_apache.conf:
+
+ PerlAccessHandler       Apache::loncacc
+
+=head1 INTRODUCTION
+
+This module enables cookie based authentication for construction area
+and is used to control access for three (essentially equivalent) URIs.
+
+ <LocationMatch "^/priv.*">
+ <LocationMatch "^/\~.*">
+ <LocationMatch "^/\~.*/$">
+
+Whenever the client sends the cookie back to the server, 
+if the cookie is missing or invalid, the user is re-challenged
+for login information.
+
+This is part of the LearningOnline Network with CAPA project
+described at http://www.lon-capa.org.
+
+=head1 HANDLER SUBROUTINE
+
+This routine is called by Apache and mod_perl.
+
+=over 4
+
+=item *
+
+load POST parameters
+
+=item *
+
+store where they wanted to go (first url entered)
+
+=back
+
+=head1 OTHERSUBROUTINES
+
+=over 4
+
+=item *
+
+constructaccess($url,$ownerdomain) : See if the owner domain and name
+in the URL match those in the expected environment.  If so, return 
+two element list ($ownername,$ownerdomain).  Else, return null string.
+
+=back
+
+=cut