--- loncom/auth/lonacc.pm	2020/10/01 21:37:16	1.159.2.5.2.4
+++ loncom/auth/lonacc.pm	2020/10/06 19:36:07	1.159.2.8.2.6
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # Cookie Based Access Handler
 #
-# $Id: lonacc.pm,v 1.159.2.5.2.4 2020/10/01 21:37:16 raeburn Exp $
+# $Id: lonacc.pm,v 1.159.2.8.2.6 2020/10/06 19:36:07 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -332,17 +332,21 @@ sub sso_login {
             ($is_balancer,$otherserver) =
                 &Apache::lonnet::check_loadbalancing($user,$domain,'login');
             if ($is_balancer) {
-                if ($otherserver eq '') {
+                # Check if browser sent a LON-CAPA load balancer cookie (and this is a balancer)
+                my ($found_server,$balancer_cookie) = &Apache::lonnet::check_for_balancer_cookie($r);
+                if (($found_server) && ($balancer_cookie =~ /^\Q$domain\E_\Q$user\E_/)) {
+                    $otherserver = $found_server;
+                } elsif ($otherserver eq '') {
                     my $lowest_load;
                     ($otherserver,undef,undef,undef,$lowest_load) = &Apache::lonnet::choose_server($domain);
                     if ($lowest_load > 100) {
                         $otherserver = &Apache::lonnet::spareserver($lowest_load,$lowest_load,1,$domain);
                     }
-                }
-                if ($otherserver ne '') {
-                    my @hosts = &Apache::lonnet::current_machine_ids();
-                    if (grep(/^\Q$otherserver\E$/,@hosts)) {
-                        $hosthere = $otherserver;
+                    if ($otherserver ne '') {
+                        my @hosts = &Apache::lonnet::current_machine_ids();
+                        if (grep(/^\Q$otherserver\E$/,@hosts)) {
+                            $hosthere = $otherserver;
+                        }
                     }
                 }
             }
@@ -505,7 +509,7 @@ sub handler {
                 my $preserved;
                 foreach my $pair (split(/&/,$query)) {
                     my ($name, $value) = split(/=/,$pair);
-                    unless ($name eq 'symb') {
+                    unless (($name eq 'symb') || ($name eq 'usehttp')) {
                         $preserved .= $pair.'&';
                     }
                     if (($env{'request.course.id'}) && ($name eq 'folderpath')) {
@@ -524,8 +528,7 @@ sub handler {
             }
         } elsif ($env{'request.course.id'} &&
                  (($requrl =~ m{^/adm/$match_domain/$match_username/aboutme$}) ||
-                  ($requrl =~ m{^/public/$cdom/$cnum/syllabus$}) ||
-                  ($requrl =~ m{^/adm/$cdom/$cnum/\d+/ext\.tool$}))) {
+                  ($requrl =~ m{^/public/$cdom/$cnum/syllabus$}))) {
             my $query = $r->args;
             if ($query) {
                 foreach my $pair (split(/&/,$query)) {
@@ -563,7 +566,7 @@ sub handler {
         my $checkexempt;
         if ($env{'user.loadbalexempt'} eq $r->dir_config('lonHostID')) {
             if ($env{'user.loadbalcheck.time'} + 600 > time) {
-                $checkexempt = 1;    
+                $checkexempt = 1;
             }
         }
         if ($env{'user.noloadbalance'} eq $r->dir_config('lonHostID')) {
@@ -573,12 +576,23 @@ sub handler {
             ($is_balancer,$otherserver) =
                 &Apache::lonnet::check_loadbalancing($env{'user.name'},
                                                      $env{'user.domain'});
+            if ($is_balancer) {
+                unless (($requrl eq '/adm/switchserver') && (!$r->is_initial_req())) {
+                    # Check if browser sent a LON-CAPA load balancer cookie (and this is a balancer)
+                    my ($found_server,$balancer_cookie) = &Apache::lonnet::check_for_balancer_cookie($r);
+                    if (($found_server) && ($balancer_cookie =~ /^\Q$env{'user.domain'}\E_\Q$env{'user.name'}\E_/)) {
+                        $otherserver = $found_server;
+                    }
+                }
+            }
         }
         if ($is_balancer) {
-            $r->set_handlers('PerlResponseHandler'=>
-                             [\&Apache::switchserver::handler]);
-            if ($otherserver ne '') {
-                $env{'form.otherserver'} = $otherserver;
+            unless (($requrl eq '/adm/switchserver') && (!$r->is_initial_req())) {
+                $r->set_handlers('PerlResponseHandler'=>
+                                 [\&Apache::switchserver::handler]);
+                if ($otherserver ne '') {
+                    $env{'form.otherserver'} = $otherserver;
+                }
             }
             unless (($env{'form.origurl'}) || ($r->uri eq '/adm/roles') ||
                     ($r->uri eq '/adm/switchserver') || ($r->uri eq '/adm/sso')) {
@@ -586,13 +600,19 @@ sub handler {
             }
         }
         if ($requrl=~m{^/+tiny/+$match_domain/+\w+$}) {
-            return OK;
+            if ($env{'user.name'} eq 'public' &&
+                $env{'user.domain'} eq 'public') {
+                $env{'request.firsturl'}=$requrl;
+                return FORBIDDEN;
+            } else {
+                return OK;
+            }
         }
 
 # ---------------------------------------------------------------- Check access
 	my $now = time;
         my $check_symb;
-	if ($requrl !~ m{^/(?:adm|public|prtspool)/}
+	if ($requrl !~ m{^/(?:adm|public|(?:prt|zip)spool)/}
 	    || $requrl =~ /^\/adm\/.*\/(smppg|bulletinboard)(\?|$ )/x) {
             my ($access,$poss_symb);
             if (($env{'request.course.id'}) && (!$suppext)) {
@@ -604,7 +624,7 @@ sub handler {
                     ($requrl=~m|\.problem/smpedit$|) ||
                     ($requrl=~/^\/public\/.*\/syllabus$/) ||
                     ($requrl=~/^\/adm\/(viewclasslist|navmaps)$/) ||
-                    ($requrl=~/^\/adm\/.*\/aboutme\/portfolio(\?|$)/)
+                    ($requrl=~/^\/adm\/.*\/aboutme\/portfolio(\?|$)/) ||
                     ($requrl=~m{^/adm/$cdom/$cnum/\d+/ext\.tool$})) {
                     $check_symb = 1;
                 }
@@ -738,9 +758,16 @@ sub handler {
 		}
 		if ($env{'form.symb'}) {
 		    $symb=&Apache::lonnet::symbclean($env{'form.symb'});
-		    if ($requrl =~ m|^/adm/wrapper/|
+                    if ($requrl eq '/adm/navmaps') {
+                        my ($map,$mid,$murl)=&Apache::lonnet::decode_symb($symb);
+                        &Apache::lonnet::symblist($map,$murl => [$murl,$mid]);
+                    } elsif ($requrl =~ m|^/adm/wrapper/|
 			|| $requrl =~ m|^/adm/coursedocs/showdoc/|) {
 			my ($map,$mid,$murl)=&Apache::lonnet::decode_symb($symb);
+                        if ($map =~ /\.page$/) {
+                            my $mapsymb = &Apache::lonnet::symbread($map);
+                            ($map,$mid,$murl)=&Apache::lonnet::decode_symb($mapsymb);
+                        }
 			&Apache::lonnet::symblist($map,$murl => [$murl,$mid],
 						  'last_known' =>[$murl,$mid]);
 		    } elsif ((&Apache::lonnet::symbverify($symb,$requrl)) ||
@@ -749,6 +776,10 @@ sub handler {
                              (($requrl=~m|(.*/aboutme)/portfolio$|) &&
                               &Apache::lonnet::symbverify($symb,$1))) {
 			my ($map,$mid,$murl)=&Apache::lonnet::decode_symb($symb);
+                        if (($map =~ /\.page$/) && ($requrl !~ /\.page$/)) {
+                            my $mapsymb = &Apache::lonnet::symbread($map);
+                            ($map,$mid,$murl)=&Apache::lonnet::decode_symb($mapsymb);
+                        }
 			&Apache::lonnet::symblist($map,$murl => [$murl,$mid],
 						  'last_known' =>[$murl,$mid]);
 		    } else {
@@ -768,19 +799,29 @@ sub handler {
                         unless (&Apache::lonnet::symbverify($symb,$requrl,\$encstate)) {
                             $invalidsymb = 1;
                             #
-                            # If $env{'request.enc'} is true, but no encryption for $symb retrieved
-                            # by original lonnet::symbread() call, call again to check for an instance
-                            # of $requrl in the course which has encryption, and set that as the symb.
-                            # If there is no such symb, or symbverify() fails for the new symb proceed
-                            # to report invalid symb.
+                            # If $env{'request.enc'} inconsistent with encryption expected for $symb
+                            # retrieved by lonnet::symbread(), call again to check for an instance of
+                            # $requrl in the course for which expected encryption matches request.enc.
+                            # If symb for different instance passes lonnet::symbverify(), use that as
+                            # the symb for $requrl and call &Apache::lonnet::allowed() for that symb.
+                            # Report invalid symb if there is no other symb. Redirect to /adm/ambiguous
+                            # if multiple possible symbs consistent with request.enc available for $requrl.
                             #
-                            if ($env{'request.enc'} && !$encstate) {
+                            if (($env{'request.enc'} && !$encstate) || (!$env{'request.enc'} && $encstate)) {
                                 my %possibles;
                                 my $nocache = 1;
+                                my $oldsymb = $symb;
                                 $symb = &Apache::lonnet::symbread($requrl,'','','',\%possibles,$nocache);
-                                if ($symb) {
+                                if (($symb) && ($symb ne $oldsymb)) {
                                     if (&Apache::lonnet::symbverify($symb,$requrl)) {
-                                        $invalidsymb = '';
+                                        my $access=&Apache::lonnet::allowed('bre',$requrl,$symb);
+                                        if ($access eq 'B') {
+                                            $env{'request.symb'} = $symb;
+                                            &Apache::blockedaccess::setup_handler($r);
+                                            return OK;
+                                        } elsif (($access eq '2') || ($access eq 'F')) {
+                                            $invalidsymb = '';
+                                        }
                                     }
                                 } elsif (keys(%possibles) > 1) {
                                     $r->internal_redirect('/adm/ambiguous');
@@ -788,18 +829,26 @@ sub handler {
                                 }
                             }
                             if ($invalidsymb) {
-			        $r->log_reason('Invalid symb for '.$requrl.': '.$symb);
-			        $env{'user.error.msg'}=
-			            "$requrl:bre:1:1:Invalid Access";
-			        return HTTP_NOT_ACCEPTABLE; 
-		            }
+                                $r->log_reason('Invalid symb for '.$requrl.': '.$symb);
+                                $env{'user.error.msg'}=
+                                    "$requrl:bre:1:1:Invalid Access";
+                                return HTTP_NOT_ACCEPTABLE;
+                            }
                         }
                     }
 		    if ($symb) {
 			my ($map,$mid,$murl)=
 			    &Apache::lonnet::decode_symb($symb);
-			&Apache::lonnet::symblist($map,$murl =>[$murl,$mid],
-						  'last_known' =>[$murl,$mid]);
+                        if ($requrl eq '/adm/navmaps') {
+                            &Apache::lonnet::symblist($map,$murl =>[$murl,$mid]);
+                        } else {
+                            if (($map =~ /\.page$/) && ($requrl !~ /\.page$/)) {
+                                my $mapsymb = &Apache::lonnet::symbread($map);
+                                ($map,$mid,$murl)=&Apache::lonnet::decode_symb($mapsymb);
+                            }
+                            &Apache::lonnet::symblist($map,$murl =>[$murl,$mid],
+                                                      'last_known' =>[$murl,$mid]);
+                        }
 		    }
 		}
 		$env{'request.symb'}=$symb;