--- loncom/auth/lonacc.pm	2020/04/06 22:16:17	1.159.2.5.4.1
+++ loncom/auth/lonacc.pm	2021/11/03 01:04:02	1.200
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # Cookie Based Access Handler
 #
-# $Id: lonacc.pm,v 1.159.2.5.4.1 2020/04/06 22:16:17 raeburn Exp $
+# $Id: lonacc.pm,v 1.200 2021/11/03 01:04:02 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -102,6 +102,7 @@ use Apache::loncommon();
 use Apache::lonlocal;
 use Apache::restrictedaccess();
 use Apache::blockedaccess();
+use Apache::lonprotected();
 use Fcntl qw(:flock);
 use LONCAPA qw(:DEFAULT :match);
 
@@ -159,7 +160,7 @@ sub get_posted_cgi {
                         if (length($value) == 1) {
                             $value=~s/[\r\n]$//;
                         }
-                    } elsif ($fname =~ /\.(xls|doc|ppt)x$/i) {
+                    } elsif ($fname =~ /\.(xls|doc|ppt)(x|m)$/i) {
                         $value=~s/[\r\n]$//;
                     }
                     if (ref($fields) eq 'ARRAY') {
@@ -202,6 +203,14 @@ sub get_posted_cgi {
 			$fname='';
 			$fmime='';
 		    }
+                    if ($i<$#lines && $lines[$i+1]=~/^Content\-Type\:\s*([\w\-\/]+)/i) {
+                        # TODO: something with $1 !
+                        $i++;
+                    }
+                    if ($i<$#lines && $lines[$i+1]=~/^Content\-transfer\-encoding\:\s*([\w\-\/]+)/i) {
+                        # TODO: something with $1 !
+                        $i++;
+                    }
 		    $i++;
 		}
 	    } else {
@@ -281,7 +290,6 @@ sub upload_size_allowed {
 sub sso_login {
     my ($r,$handle,$username) = @_;
 
-    my $lonidsdir=$r->dir_config('lonIDsDir');
     if (($r->user eq '') || ($username ne '') || ($r->user eq 'public:public') ||
         (defined($env{'user.name'}) && (defined($env{'user.domain'}))
 	  && ($handle ne ''))) {
@@ -297,7 +305,8 @@ sub sso_login {
     my $query = $r->args;
     my %form;
     if ($query) {
-        my @items = ('role','symb','iptoken');
+        my @items = ('role','symb','iptoken','origurl','ttoken',
+                     'ltoken','linkkey','logtoken','sso');
         &Apache::loncommon::get_unprocessed_cgi($query,\@items);
         foreach my $item (@items) {
             if (defined($env{'form.'.$item})) {
@@ -315,6 +324,101 @@ sub sso_login {
         }
     }
 
+    my ($linkprot,$linkkey);
+
+#
+# If Shibboleth auth is in use, and a dual SSO and non-SSO login page
+# is in use, then the query string will contain the logtoken item with
+# a value set to the name of a .tmp file in /home/httpd/perl/tmp
+# containing the url to display after authentication, and also,
+# optionally, role and symb, or linkprot or linkkey (deep-link access).
+#
+# If Shibboleth auth is in use, but a dual log-in page is not in use,
+# and the originally requested URL was /tiny/$domain/$id (i.e.,
+# for deeplinking), then the query string will contain the sso item
+# with a value set to the name of a .tmp file in /home/httpd/perl/tmp
+# containing the url to display after authentication, and also,
+# optionally, linkprot or linkkey (deep-link access).
+#
+# Otherwise the query string may contain role and symb, or if the
+# originally requested URL was /tiny/$domain/$id (i.e. for deeplinking)
+# then the query string may contain a ttoken item with a value set
+# to the name of a .tmp file in /home/httpd/perl/tmp containing either
+# linkprot or linkkey (deep-link access).
+#
+# If deep-linked, i.e., the originally requested URL was /tiny/$domain/$id
+# the linkkey may have originally been sent in POSTed data, which will
+# have been processed in lontrans.pm
+#
+
+    if ($form{'ttoken'}) {
+        my %info = &Apache::lonnet::tmpget($form{'ttoken'});
+        &Apache::lonnet::tmpdel($form{'ttoken'});
+        if ($info{'origurl'}) {
+            $form{'origurl'} = $info{'origurl'};
+        }
+        if ($info{'linkprot'}) {
+            $linkprot = $info{'linkprot'};
+        } elsif ($info{'linkkey'} ne '') {
+            $linkkey = $info{'linkkey'};
+        }
+    } elsif ($form{'logtoken'}) {
+        my ($firsturl,@rest);
+        my $lonhost = $r->dir_config('lonHostID');
+        my $tmpinfo = &Apache::lonnet::reply('tmpget:'.$form{'logtoken'},$lonhost);
+        my $delete = &Apache::lonnet::tmpdel($form{'logtoken'});
+        unless (($tmpinfo=~/^error/) || ($tmpinfo eq 'con_lost') ||
+                ($tmpinfo eq 'no_such_host')) {
+            (undef,$firsturl,@rest) = split(/&/,$tmpinfo);
+            if ($firsturl ne '') {
+                $firsturl = &unescape($firsturl);
+            }
+            foreach my $item (@rest) {
+                my ($key,$value) = split(/=/,$item);
+                $form{$key} = &unescape($value);
+            }
+            if ($firsturl =~ m{^/tiny/$match_domain/\w+$}) {
+                $form{'origurl'} = $firsturl;
+            }
+            if ($form{'linkprot'}) {
+                $linkprot = $form{'linkprot'};
+            } elsif ($form{'linkkey'} ne '') {
+                $linkkey = $form{'linkkey'};
+            }
+            if ($form{'iptoken'}) {
+                %sessiondata = &Apache::lonnet::tmpget($form{'iptoken'});
+                my $delete = &Apache::lonnet::tmpdel($form{'iptoken'});
+            }
+        }
+    } elsif ($form{'sso'}) {
+        my $lonhost = $r->dir_config('lonHostID');
+        my $info = &Apache::lonnet::reply('tmpget:'.$form{'sso'},$lonhost);
+        &Apache::lonnet::tmpdel($form{'sso'});
+        unless (($info=~/^error/) || ($info eq 'con_lost') ||
+                ($info eq 'no_such_host')) {
+            my ($firsturl,@rest)=split(/\&/,$info);
+            if ($firsturl ne '') {
+                $form{'origurl'} = &unescape($firsturl);
+            }
+            foreach my $item (@rest) {
+                my ($key,$value) = split(/=/,$item);
+                $form{$key} = &unescape($value);
+            }
+            if ($form{'linkprot'}) {
+                $linkprot = $form{'linkprot'};
+            } elsif ($form{'linkkey'} ne '') {
+                $linkkey = $form{'linkkey'};
+            }
+        }
+    } elsif ($form{'ltoken'}) {
+        my %link_info = &Apache::lonnet::tmpget($form{'ltoken'});
+        $linkprot = $link_info{'linkprot'};
+        my $delete = &Apache::lonnet::tmpdel($form{'ltoken'});
+        delete($form{'ltoken'});
+    } elsif ($form{'linkkey'} ne '') {
+        $linkkey = $form{'linkkey'};
+    }
+
     my $domain = $r->dir_config('lonSSOUserDomain');
     if ($domain eq '') {
         $domain = $r->dir_config('lonDefDomain');
@@ -333,17 +437,21 @@ sub sso_login {
             ($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);
+                        $otherserver = &Apache::lonnet::spareserver($r,$lowest_load,$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 = $otherserver;
+                        }
                     }
                 }
             }
@@ -352,6 +460,26 @@ sub sso_login {
 	    # login but immediately go to switch server to find us a new 
 	    # machine
 	    &Apache::lonauth::success($r,$user,$domain,$home,'noredirect');
+            foreach my $item (keys(%form)) {
+                $env{'form.'.$item} = $form{$item};
+            }
+            unless (($form{'symb'}) || ($form{'origurl'})) {
+                unless (($r->uri eq '/adm/roles') || ($r->uri eq '/adm/sso')) {
+                    $env{'form.origurl'} = $r->uri;
+                }
+            }
+            if (($r->uri eq '/adm/sso') && ($form{'origurl'} =~ m{^/+tiny/+$match_domain/+\w+$})) {
+                $env{'request.deeplink.login'} = $form{'origurl'};
+            } elsif ($r->uri =~ m{^/+tiny/+$match_domain/+\w+$}) {
+                $env{'request.deeplink.login'} = $r->uri;
+            }
+            if ($env{'request.deeplink.login'}) {
+                if ($linkprot) {
+                    $env{'request.linkprot'} = $linkprot;
+                } elsif ($linkkey ne '') {
+                    $env{'request.linkkey'} = $linkkey;
+                }
+            }
             $env{'request.sso.login'} = 1;
             if (defined($r->dir_config("lonSSOReloginServer"))) {
                 $env{'request.sso.reloginserver'} =
@@ -366,23 +494,37 @@ sub sso_login {
 	} else {
 	    # need to login them in, so generate the need data that
 	    # migrate expects to do login
-            my $ip = $r->get_remote_host();
+	    my $ip = &Apache::lonnet::get_requestor_ip($r);
 	    my %info=('ip'        => $ip,
 		      'domain'    => $domain,
 		      'username'  => $user,
 		      'server'    => $r->dir_config('lonHostID'),
 		      'sso.login' => 1
 		      );
-            foreach my $item ('role','symb','iptoken') {
+            foreach my $item ('role','symb','iptoken','origurl') {
                 if (exists($form{$item})) {
                     $info{$item} = $form{$item};
+                } elsif ($sessiondata{$item} ne '') {
+                    $info{$item} = $sessiondata{$item};
                 }
             }
-            unless ($info{'symb'}) {
+            unless (($info{'symb'}) || ($info{'origurl'})) {
                 unless (($r->uri eq '/adm/roles') || ($r->uri eq '/adm/sso')) {
                     $info{'origurl'} = $r->uri; 
                 }
             }
+            if (($r->uri eq '/adm/sso') && ($form{'origurl'} =~ m{^/+tiny/+$match_domain/+\w+$})) {
+                $info{'deeplink.login'} = $form{'origurl'};
+            } elsif ($r->uri =~ m{^/+tiny/+$match_domain/+\w+$}) {
+                $info{'deeplink.login'} = $r->uri;
+            }
+            if ($info{'deeplink.login'}) {
+                if ($linkprot) {
+                    $info{'linkprot'} = $linkprot;
+                } elsif ($linkkey ne '') {
+                    $info{'linkkey'} = $linkkey;
+                }
+            }
             if ($r->dir_config("ssodirecturl") == 1) {
                 $info{'origurl'} = $r->uri;
             }
@@ -420,6 +562,8 @@ sub sso_login {
             $r->subprocess_env->set('SSOUserUnknown' => $user);
             $r->subprocess_env->set('SSOUserDomain' => $domain);
             if (grep(/^sso$/,@cancreate)) {
+#FIXME - need to preserve origurl, role and symb, or linkprot or linkkey for use after account
+# creation
                 $r->set_handlers('PerlHandler'=> [\&Apache::createaccount::handler]);
                 $r->handler('perl-script');
             } else {
@@ -459,7 +603,7 @@ sub handler {
     if ($handle eq '') {
         unless ((($requrl eq '/adm/switchserver') && (!$r->is_initial_req())) ||
                 ($requrl =~ m{^/public/$match_domain/$match_courseid/syllabus}) ||
-                ($requrl =~ m{^/adm/help/}) ||
+                ($requrl =~ m{^/adm/help/}) || ($requrl eq '/adm/sso') ||
                 ($requrl =~ m{^/res/$match_domain/$match_username/})) {
 	    $r->log_reason("Cookie not valid", $r->filename);
         }
@@ -498,7 +642,7 @@ 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'}) && ($name eq 'folderpath')) {
@@ -517,7 +661,7 @@ sub handler {
             }
         } elsif ($env{'request.course.id'} &&
                  (($requrl =~ m{^/adm/$match_domain/$match_username/aboutme$}) ||
-                  ($requrl =~ m{^/public/$cdom/$cnum/syllabus$}) ||
+                  ($requrl eq "/public/$cdom/$cnum/syllabus") ||
                   ($requrl =~ m{^/adm/$cdom/$cnum/\d+/ext\.tool$}))) {
             my $query = $r->args;
             if ($query) {
@@ -527,6 +671,7 @@ sub handler {
                         if ($value =~ /^supplemental/) {
                             $suppext = 1;
                         }
+                        last;
                     }
                 }
             }
@@ -538,7 +683,8 @@ sub handler {
             my $hostname = $r->hostname();
             my $lonhost = &Apache::lonnet::host_from_dns($hostname);
             if ($lonhost) {
-                my $actual = &Apache::lonnet::absolute_url($hostname);
+                my $actual = &Apache::lonnet::absolute_url($hostname,1,1);
+                my $exphostname = &Apache::lonnet::hostname($lonhost);
                 my $expected = $Apache::lonnet::protocol{$lonhost}.'://'.$hostname;
                 unless ($actual eq $expected) {
                     $env{'request.use_absolute'} = $expected;
@@ -554,34 +700,140 @@ 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')) {
             $checkexempt = 1;
         }
-        unless ($checkexempt) {
+        unless (($checkexempt) || (($requrl eq '/adm/switchserver') && (!$r->is_initial_req()))) {
             ($is_balancer,$otherserver) =
                 &Apache::lonnet::check_loadbalancing($env{'user.name'},
                                                      $env{'user.domain'});
-        }
-        if ($is_balancer) {
-            $r->set_handlers('PerlResponseHandler'=>
-                             [\&Apache::switchserver::handler]);
-            if ($otherserver ne '') {
-                $env{'form.otherserver'} = $otherserver;
+            if ($is_balancer) {
+                # 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 = $found_server;
+                }
+                unless ($requrl eq '/adm/switchserver') {
+                    $r->set_handlers('PerlResponseHandler'=>
+                                     [\&Apache::switchserver::handler]);
+                }
+                if ($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')) {
+                    $env{'form.origurl'} = $r->uri;
+                }
             }
-            unless (($env{'form.origurl'}) || ($r->uri eq '/adm/roles') ||
-                    ($r->uri eq '/adm/switchserver') || ($r->uri eq '/adm/sso')) {
-                $env{'form.origurl'} = $r->uri;
+        }
+        if ($requrl=~m{^/+tiny/+$match_domain/+\w+$}) {
+            if ($env{'user.name'} eq 'public' &&
+                $env{'user.domain'} eq 'public') {
+                $env{'request.firsturl'}=$requrl;
+                return FORBIDDEN;
+            } else {
+                return OK;
             }
         }
-
 # ---------------------------------------------------------------- Check access
 	my $now = time;
-	if ($requrl !~ m{^/(?:adm|public|prtspool)/}
+        my ($check_symb,$check_access,$check_block,$access,$poss_symb);
+	if ($requrl !~ m{^/(?:adm|public|(?:prt|zip)spool)/}
 	    || $requrl =~ /^\/adm\/.*\/(smppg|bulletinboard)(\?|$ )/x) {
-	    my $access=&Apache::lonnet::allowed('bre',$requrl);
+            $check_access = 1;
+        }
+        if ((!$check_access) && ($env{'request.course.id'})) {
+            if (($requrl eq '/adm/viewclasslist') ||
+                ($requrl =~ m{^(/adm/wrapper|)\Q/uploaded/$cdom/$cnum/docs/\E}) ||
+                ($requrl =~ m{^/adm/.*/aboutme$}) ||
+                ($requrl=~m{^/adm/coursedocs/showdoc/}) ||
+                ($requrl=~m{^(/adm/wrapper|)/adm/$cdom/$cnum/\d+/ext\.tool$})) {
+                $check_block = 1;
+            }
+        }
+        if (($env{'request.course.id'}) && (!$suppext)) {
+            $requrl=~/\.(\w+)$/;
+            if ((&Apache::loncommon::fileembstyle($1) eq 'ssi') ||
+                ($requrl=~/^\/adm\/.*\/(aboutme|smppg|bulletinboard)(\?|$ )/x) ||
+                ($requrl=~/^\/adm\/wrapper\//) ||
+                ($requrl=~m|^/adm/coursedocs/showdoc/|) ||
+                ($requrl=~m|\.problem/smpedit$|) ||
+                ($requrl=~/^\/public\/.*\/syllabus$/) ||
+                ($requrl=~/^\/adm\/(viewclasslist|navmaps)$/) ||
+                ($requrl=~/^\/adm\/.*\/aboutme\/portfolio(\?|$)/) ||
+                ($requrl=~m{^/adm/$cdom/$cnum/\d+/ext\.tool$})) {
+                $check_symb = 1;
+            }
+        }
+        if (($check_access) || ($check_block)) {
+            if ($check_symb) {
+                if ($env{'form.symb'}) {
+                    $poss_symb=&Apache::lonnet::symbclean($env{'form.symb'});
+                } elsif (($env{'request.course.id'}) && ($r->args ne '')) {
+                    my $query = $r->args;
+                    foreach my $pair (split(/&/,$query)) {
+                        my ($name, $value) = split(/=/,$pair);
+                        $name = &unescape($name);
+                        $value =~ tr/+/ /;
+                        $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg;
+                        if ($name eq 'symb') {
+                            $poss_symb = &Apache::lonnet::symbclean($value);
+                            last;
+                        }
+                    }
+                }
+                if ($poss_symb) {
+                    my ($possmap,$resid,$url)=&Apache::lonnet::decode_symb($poss_symb);
+                    $url = &Apache::lonnet::clutter($url);
+                    my $toplevelmap = $env{'course.'.$env{'request.course.id'}.'.url'};
+                    unless (($url eq $requrl) && (($possmap eq $toplevelmap) ||
+                                                  (&Apache::lonnet::is_on_map($possmap)))) {
+                        undef($poss_symb);
+                    }
+                    if ($poss_symb) {
+                        if ((!$env{'request.role.adv'}) && ($env{'acc.randomout'}) &&
+                            ($env{'acc.randomout'}=~/\&\Q$poss_symb\E\&/)) {
+                            undef($poss_symb);
+                        } elsif ((!$env{'request.role.adv'}) && ($env{'acc.deeplinkout'}) &&
+                                 ($env{'acc.deeplinkout'}=~/\&\Q$poss_symb\E\&/)) {
+                            undef($poss_symb);
+                        }
+                    }
+                }
+                if ($poss_symb) {
+                    $access=&Apache::lonnet::allowed('bre',$requrl,$poss_symb);
+                } else {
+                    $access=&Apache::lonnet::allowed('bre',$requrl,'','','','',1);
+                }
+            } else {
+                my $nodeeplinkcheck;
+                if (($check_access) && ($requrl =~ /\.(sequence|page)$/)) {
+                    unless ($env{'form.navmap'}) {
+                        if ($r->args ne '') {
+                            &Apache::loncommon::get_unprocessed_cgi($r->args,['navmap']);
+                            unless ($env{'form.navmap'}) {
+                                $nodeeplinkcheck = 1;
+                            }
+                        }
+                    }
+                }
+                $access=&Apache::lonnet::allowed('bre',$requrl,'','','','','',$nodeeplinkcheck);
+            }
+        }
+        if ($check_block) {
+            if ($access eq 'B') {
+                if ($poss_symb) {
+                    if (&Apache::lonnet::symbverify($poss_symb,$requrl)) {
+                        $env{'request.symb'} = $poss_symb;
+                    }
+                }
+                &Apache::blockedaccess::setup_handler($r);
+                return OK;
+            }
+        } elsif ($check_access) {
             if ($handle eq '') {
                 unless ($access eq 'F') {
                     if ($requrl =~ m{^/res/$match_domain/$match_username/}) {
@@ -598,9 +850,18 @@ sub handler {
 		return OK;
 	    }
             if ($access eq 'B') {
+                if ($poss_symb) {
+                    if (&Apache::lonnet::symbverify($poss_symb,$requrl)) {
+                        $env{'request.symb'} = $poss_symb;
+                    }
+                }
                 &Apache::blockedaccess::setup_handler($r);
                 return OK;
             }
+            if ($access eq 'D') {
+                &Apache::lonprotected::setup_handler($r);
+                return OK;
+            }
 	    if (($access ne '2') && ($access ne 'F')) {
                 if ($requrl =~ m{^/res/}) {
                     $access = &Apache::lonnet::allowed('bro',$requrl);
@@ -617,7 +878,7 @@ sub handler {
                         }
                     }
                 } elsif (($handle =~ /^publicuser_\d+$/) && (&Apache::lonnet::is_portfolio_url($requrl))) {
-                    my $clientip = $r->get_remote_host();
+                    my $clientip = &Apache::lonnet::get_requestor_ip($r);
                     if (&Apache::lonnet::allowed('bre',$requrl,undef,undef,$clientip) ne 'F') {
                         $env{'user.error.msg'}="$requrl:bre:1:1:Access Denied";
                         return HTTP_NOT_ACCEPTABLE;
@@ -648,7 +909,7 @@ sub handler {
 	    $env{'user.domain'} eq 'public' &&
 	    $requrl !~ m{^/+(res|public|uploaded)/} &&
 	    $requrl !~ m{^/adm/[^/]+/[^/]+/aboutme/portfolio$ }x &&
-        $requrl !~ m{^/adm/blockingstatus/.*$} &&
+            $requrl !~ m{^/adm/blockingstatus/.*$} &&
 	    $requrl !~ m{^/+adm/(help|logout|restrictedaccess|randomlabel\.png)}) {
 	    $env{'request.querystring'}=$r->args;
 	    $env{'request.firsturl'}=$requrl;
@@ -657,17 +918,8 @@ sub handler {
 # ------------------------------------------------------------- This is allowed
 	if ($env{'request.course.id'}) {
 	    &Apache::lonnet::countacc($requrl);
-	    $requrl=~/\.(\w+)$/;
             my $query=$r->args;
-	    if ((&Apache::loncommon::fileembstyle($1) eq 'ssi') ||
-		($requrl=~/^\/adm\/.*\/(aboutme|smppg|bulletinboard)(\?|$ )/x) ||
-		($requrl=~/^\/adm\/wrapper\//) ||
-		($requrl=~m|^/adm/coursedocs/showdoc/|) ||
-		($requrl=~m|\.problem/smpedit$|) ||
-		($requrl=~/^\/public\/.*\/syllabus$/) ||
-                ($requrl=~/^\/adm\/(viewclasslist|navmaps)$/) ||
-                ($requrl=~/^\/adm\/.*\/aboutme\/portfolio(\?|$)/) ||
-                ($requrl=~m{^/adm/$cdom/$cnum/\d+/ext\.tool$})) {
+            if ($check_symb) {
 # ------------------------------------- This is serious stuff, get symb and log
 		my $symb;
 		if ($query) {
@@ -675,17 +927,42 @@ sub handler {
 		}
 		if ($env{'form.symb'}) {
 		    $symb=&Apache::lonnet::symbclean($env{'form.symb'});
-		    if ($requrl =~ m|^/adm/wrapper/|
-			|| $requrl =~ m|^/adm/coursedocs/showdoc/|) {
-			my ($map,$mid,$murl)=&Apache::lonnet::decode_symb($symb);
-			&Apache::lonnet::symblist($map,$murl => [$murl,$mid],
-						  'last_known' =>[$murl,$mid]);
+                    if (($requrl eq '/adm/navmaps') ||
+                        ($requrl =~ m{^/adm/wrapper/}) ||
+                        ($requrl =~ m{^/adm/coursedocs/showdoc/})) {
+                        unless (&Apache::lonnet::symbverify($symb,$requrl)) {
+                            if (&Apache::lonnet::is_on_map($requrl)) {
+                                $symb = &Apache::lonnet::symbread($requrl);
+                                unless (&Apache::lonnet::symbverify($symb,$requrl)) {
+                                    undef($symb);
+                                }
+                            }
+                        }
+                        if ($symb) {
+                            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)) ||
 			     (($requrl=~m|(.*)/smpedit$|) &&
 			      &Apache::lonnet::symbverify($symb,$1)) ||
                              (($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 {
@@ -699,24 +976,72 @@ sub handler {
                     if ($requrl=~m{^(/adm/.*/aboutme)/portfolio$}) {
                         $requrl = $1;
                     }
-                    unless ($suppext) {
-		        $symb=&Apache::lonnet::symbread($requrl);
-		        if (&Apache::lonnet::is_on_map($requrl) && $symb &&
-			    !&Apache::lonnet::symbverify($symb,$requrl)) {
-			    $r->log_reason('Invalid symb for '.$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);
+		    $symb=&Apache::lonnet::symbread($requrl);
+                    if (&Apache::lonnet::is_on_map($requrl) && $symb) {
+                        my ($encstate,$invalidsymb);
+                        unless (&Apache::lonnet::symbverify($symb,$requrl,\$encstate)) {
+                            $invalidsymb = 1;
+                            #
+                            # 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'} && !$encstate) || (!$env{'request.enc'} && $encstate)) {
+                                my %possibles;
+                                my $nocache = 1;
+                                my $oldsymb = $symb;
+                                $symb = &Apache::lonnet::symbread($requrl,'','','',\%possibles,$nocache);
+                                if (($symb) && ($symb ne $oldsymb)) {
+                                    if (&Apache::lonnet::symbverify($symb,$requrl)) {
+                                        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) {
+                                    $r->internal_redirect('/adm/ambiguous');
+                                    return OK;
+                                }
+                            }
+                            if ($invalidsymb) {
+                                if ($requrl eq '/adm/navmaps') {
+                                    undef($symb);
+                                } else {
+                                    $r->log_reason('Invalid symb for '.$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($symb);
+                        if ($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;
+                if (($env{'request.symbread.cached.'}) && ($env{'request.symbread.cached.'} ne $symb)) {
+                    $env{'request.symbread.cached.'} = $symb;
+                }
 		&Apache::lonnet::courseacclog($symb);
 	    } else {
 # ------------------------------------------------------- This is other content
@@ -761,8 +1086,8 @@ sub handler {
     }
 # ------------------------------------ See if this is a viewable portfolio file
     if (&Apache::lonnet::is_portfolio_url($requrl)) {
-        my $clientip = $r->get_remote_host();
-	my $access=&Apache::lonnet::allowed('bre',$requrl,undef,undef,$clientip);
+        my $clientip = &Apache::lonnet::get_requestor_ip($r);
+        my $access=&Apache::lonnet::allowed('bre',$requrl,undef,undef,$clientip);
 	if ($access eq 'A') {
 	    &Apache::restrictedaccess::setup_handler($r);
 	    return OK;