--- loncom/auth/loncacc.pm	2008/11/12 20:01:09	1.47
+++ loncom/auth/loncacc.pm	2011/11/12 19:37:40	1.59
@@ -2,7 +2,7 @@
 # Cookie Based Access Handler for Construction Area
 # (lonacc: 5/21/99,5/22,5/29,5/31 Gerd Kortemeyer)
 #
-# $Id: loncacc.pm,v 1.47 2008/11/12 20:01:09 jms Exp $
+# $Id: loncacc.pm,v 1.59 2011/11/12 19:37:40 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -42,11 +42,11 @@ Invoked (for various locations) by /etc/
 =head1 INTRODUCTION
 
 This module enables cookie based authentication for construction area
-and is used to control access for three (essentially equivalent) URIs.
+and is used to control access for the following two types of URI 
+(one for files, and one for directories):
 
  <LocationMatch "^/priv.*">
- <LocationMatch "^/\~.*">
- <LocationMatch "^/\~.*/$">
+ <LocationMatch "^/priv.*/$">
 
 Whenever the client sends the cookie back to the server, 
 if the cookie is missing or invalid, the user is re-challenged
@@ -73,13 +73,20 @@ store where they wanted to go (first url
 
 =head1 OTHERSUBROUTINES
 
-=over 4
+=over
 
-=item *
+=item constructaccess($url,$setpriv)
 
-constructaccess($url,$ownerdomain) : See if the owner domain and name
+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.
+three element list ($ownername,$ownerdomain,$ownerhome).  
+
+Otherwise return the null string.
+
+If second argument 'setpriv' is true, it assigns the privileges,
+and returns the same three element list, unless the owner has
+blocked "ad hoc" Domain Coordinator access to the Author Space,
+in which case the null string is returned.
 
 =back
 
@@ -97,26 +104,68 @@ use Apache::lonacc;
 use LONCAPA qw(:DEFAULT :match);
 
 sub constructaccess {
-    my ($url,$ownerdomain)=@_;
-    my ($ownername)=($url=~/\/(?:\~|priv\/|home\/)($match_username)\//);
-    unless (($ownername) && ($ownerdomain)) { return ''; }
-    # We do not allow editing of previous versions of files.
+    my ($url,$setpriv)=@_;
+
+# We do not allow editing of previous versions of files
     if ($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);
-	    }
+
+# Get username and domain from URL
+    my $londocroot = $Apache::lonnet::perlvar{'lonDocRoot'};
+    my ($ownername,$ownerdomain,$ownerhome);
+
+    ($ownerdomain,$ownername) = 
+        ($url=~ m{^(?:\Q$londocroot\E|)/priv/($match_domain)/($match_username)/});
+
+# The URL does not really point to any authorspace, forget it
+    unless (($ownername) && ($ownerdomain)) { return ''; }
+
+# Now we need to see if the user has access to the authorspace of
+# $ownername at $ownerdomain
+
+    if (($ownername eq $env{'user.name'}) && ($ownerdomain eq $env{'user.domain'})) {
+# Real author for this?
+       $ownerhome = $env{'user.home'};
+       if (exists($env{'user.priv.au./'.$ownerdomain.'/./'})) {
+          return ($ownername,$ownerdomain,$ownerhome);
+       }
+    } else {
+# Co-author for this?
+	if (exists($env{'user.priv.ca./'.$ownerdomain.'/'.$ownername.'./'}) ||
+	    exists($env{'user.priv.aa./'.$ownerdomain.'/'.$ownername.'./'}) ) {
+	    $ownerhome = &Apache::lonnet::homeserver($ownername,$ownerdomain);
+	    return ($ownername,$ownerdomain,$ownerhome);
 	}
     }
-    
-    foreach my $domain (@possibledomains) {
-	if (exists($env{'user.priv.ca./'.$domain.'/'.$ownername.'./'}) ||
-	    exists($env{'user.priv.aa./'.$domain.'/'.$ownername.'./'}) ) {
-	    return ($ownername,$domain);
-	}
+# We don't have any access right now. If we are not possibly going to do anything about this,
+# we might as well leave
+   unless ($setpriv) { return ''; }
+
+# Backdoor access?
+    my $allowed=&Apache::lonnet::allowed('eco',$ownerdomain);
+# Nope
+    unless ($allowed) { return ''; }
+# Looks like we may have access, but could be locked by the owner of the construction space
+    if ($allowed eq 'U') {
+        my %blocked=&Apache::lonnet::get('environment',['domcoord.author'],
+                                         $ownerdomain,$ownername);
+# Is blocked by owner
+        if ($blocked{'domcoord.author'} eq 'blocked') { return ''; }
+    }
+    if (($allowed eq 'F') || ($allowed eq 'U')) {
+# Grant temporary access
+        my $then=$env{'user.login.time'};
+        my $update==$env{'user.update.time'};
+        if (!$update) { $update = $then; }
+        my $refresh=$env{'user.refresh.time'};
+        if (!$refresh) { $refresh = $update; }
+        my $now = time;
+        &Apache::lonnet::check_adhoc_privs($ownerdomain,$ownername,
+                                           $update,$refresh,$now,'ca',
+                                           'constructaccess');
+        $ownerhome = &Apache::lonnet::homeserver($ownername,$ownerdomain);
+        return($ownername,$ownerdomain,$ownerhome);
     }
+# No business here
     return '';
 }
 
@@ -141,7 +190,18 @@ sub handler {
 	$env{'request.state'}    = "construct";
 	$env{'request.filename'} = $r->filename;
 
-	unless (&constructaccess($requrl,$r->dir_config('lonDefDomain'))) {
+	my $allowed;
+	my ($ownername,$ownerdom,$ownerhome) = &constructaccess($requrl,'setpriv');
+        if (($ownername ne '') && ($ownerdom ne '') && ($ownerhome ne '')) {
+            unless ($ownerhome eq 'no_host') {
+                my @hosts = &Apache::lonnet::current_machine_ids();
+                if (grep(/^\Q$ownerhome\E$/,@hosts)) {
+                    $allowed = 1;
+                }
+            }
+        }
+
+        unless ($allowed) {
 	    $r->log_reason("Unauthorized $requrl", $r->filename); 
 	    return HTTP_NOT_ACCEPTABLE;
 	}
@@ -151,7 +211,7 @@ sub handler {
 	&Apache::lonacc::get_posted_cgi($r);
 
 	return OK; 
-    } else { 
+    } else {
 	$r->log_reason("Cookie $handle not valid", $r->filename) 
     }
 
@@ -164,10 +224,3 @@ sub handler {
 1;
 __END__
 
-
-
-
-
-
-
-