--- loncom/auth/loncacc.pm	1999/10/13 17:48:52	1.1.1.1
+++ loncom/auth/loncacc.pm	2003/06/11 00:39:46	1.29
@@ -1,17 +1,73 @@
 # 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 1.29 2003/06/11 00:39:46 www 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/
+#
+# YEAR=2000
+# 6/15,16/11,22/11,
+# YEAR=2001
+# 01/06,01/11,6/1,9/25,9/28,11/22,12/25,12/26,
+# 01/06/01,05/04,05/05,05/09 Gerd Kortemeyer
+# YEAR=2002
+# 1/4 Gerd Kortemeyer
+###
 
 package Apache::loncacc;
 
 use strict;
-use Apache::Constants qw(:common :http);
+use Apache::Constants qw(:common :http :methods REDIRECT);
+use Apache::File;
 use CGI::Cookie();
+use Fcntl qw(:flock);
+
+sub constructaccess {
+    my ($url,$ownerdomain)=@_;
+    my ($ownername)=($url=~/\/(?:\~|priv\/|home\/)(\w+)/);
+    unless (($ownername) && ($ownerdomain)) { return ''; }
+    # We do not allow editing of previous versions of files.
+    if ($url=~/\.(\d+)\.(\w+)$/) { return ''; }
+    if (($ownername eq $ENV{'user.name'}) &&
+        ($ownerdomain eq $ENV{'user.domain'})) {
+	return ($ownername,$ownerdomain);
+    }
+
+    my $capriv='user.priv.ca./'.
+               $ownerdomain.'/'.$ownername.'./';
+    foreach (keys %ENV) {
+        if ($_ eq $capriv) {
+           return ($ownername,$ownerdomain);
+        }
+    }
+    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;
@@ -20,32 +76,104 @@ sub handler {
         $handle=~s/\W//g;
         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);
+
+# -------------------------------------------------------------- Resource State
+
+            $ENV{'request.state'}    = "construct";
+            $ENV{'request.filename'} = $r->filename;
+
+            unless (&constructaccess($requrl,$r->dir_config('lonDefDomain'))) {
+                $r->log_reason("Unauthorized $requrl", $r->filename); 
 	        return HTTP_NOT_ACCEPTABLE;
             }
+# Construction space needs Remote to work
+            if ($ENV{'environment.remote'} eq 'off') {
+	        $r->content_type('text/html');
+                $r->header_out(Location => 
+                    'http://'.$r->server->server_hostname.
+                    '/adm/remote?action=launch&url='.
+                    &Apache::lonnet::escape($requrl));
+                return REDIRECT;
+            }
+
+# -------------------------------------------------------- Load POST parameters
+
+	    &Apache::loncommon::get_posted_cgi($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