--- loncom/interface/loncommon.pm	2017/03/15 03:39:49	1.1075.2.125
+++ loncom/interface/loncommon.pm	2020/05/25 18:46:14	1.1075.2.127.2.10
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # a pile of common routines
 #
-# $Id: loncommon.pm,v 1.1075.2.125 2017/03/15 03:39:49 raeburn Exp $
+# $Id: loncommon.pm,v 1.1075.2.127.2.10 2020/05/25 18:46:14 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -80,6 +80,10 @@ use JSON::DWIW;
 use LWP::UserAgent;
 use Crypt::DES;
 use DynaLoader; # for Crypt::DES version
+use File::Copy();
+use File::Path();
+use String::CRC32();
+use Short::URL();
 
 # ---------------------------------------------- Designs
 use vars qw(%defaultdesign);
@@ -194,7 +198,7 @@ BEGIN {
     {
         my $langtabfile = $Apache::lonnet::perlvar{'lonTabDir'}.
                                    '/language.tab';
-        if ( open(my $fh,"<$langtabfile") ) {
+        if ( open(my $fh,'<',$langtabfile) ) {
             while (my $line = <$fh>) {
                 next if ($line=~/^\#/);
                 chomp($line);
@@ -215,7 +219,7 @@ BEGIN {
     {
         my $copyrightfile = $Apache::lonnet::perlvar{'lonIncludes'}.
                                   '/copyright.tab';
-        if ( open (my $fh,"<$copyrightfile") ) {
+        if ( open (my $fh,'<',$copyrightfile) ) {
             while (my $line = <$fh>) {
                 next if ($line=~/^\#/);
                 chomp($line);
@@ -229,7 +233,7 @@ BEGIN {
     {
         my $sourcecopyrightfile = $Apache::lonnet::perlvar{'lonIncludes'}.
                                   '/source_copyright.tab';
-        if ( open (my $fh,"<$sourcecopyrightfile") ) {
+        if ( open (my $fh,'<',$sourcecopyrightfile) ) {
             while (my $line = <$fh>) {
                 next if ($line =~ /^\#/);
                 chomp($line);
@@ -243,7 +247,7 @@ BEGIN {
 # -------------------------------------------------------------- default domain designs
     my $designdir=$Apache::lonnet::perlvar{'lonTabDir'}.'/lonDomColors';
     my $designfile = $designdir.'/default.tab';
-    if ( open (my $fh,"<$designfile") ) {
+    if ( open (my $fh,'<',$designfile) ) {
         while (my $line = <$fh>) {
             next if ($line =~ /^\#/);
             chomp($line);
@@ -257,7 +261,7 @@ BEGIN {
     {
         my $categoryfile = $Apache::lonnet::perlvar{'lonTabDir'}.
                                   '/filecategories.tab';
-        if ( open (my $fh,"<$categoryfile") ) {
+        if ( open (my $fh,'<',$categoryfile) ) {
 	    while (my $line = <$fh>) {
 		next if ($line =~ /^\#/);
 		chomp($line);
@@ -272,7 +276,7 @@ BEGIN {
     {
         my $typesfile = $Apache::lonnet::perlvar{'lonTabDir'}.
                '/filetypes.tab';
-        if ( open (my $fh,"<$typesfile") ) {
+        if ( open (my $fh,'<',$typesfile) ) {
             while (my $line = <$fh>) {
 		next if ($line =~ /^\#/);
 		chomp($line);
@@ -4612,7 +4616,8 @@ sub blockcheck {
     # boards, chat or groups, check for blocking in current course only.
 
     if (($activity eq 'boards' || $activity eq 'chat' ||
-         $activity eq 'groups' || $activity eq 'printout') &&
+         $activity eq 'groups' || $activity eq 'printout' ||
+         $activity eq 'reinit' || $activity eq 'alert') &&
         ($env{'request.course.id'})) {
         foreach my $key (keys(%live_courses)) {
             if ($key ne $env{'request.course.id'}) {
@@ -4923,6 +4928,10 @@ END_MYBLOCK
         $text = &mt('Printing Blocked');
     } elsif ($activity eq 'passwd') {
         $text = &mt('Password Changing Blocked');
+    } elsif ($activity eq 'alert') {
+        $text = &mt('Checking Critical Messages Blocked');
+    } elsif ($activity eq 'reinit') {
+        $text = &mt('Checking Course Update Blocked');
     }
     $output .= <<"END_BLOCK";
 <div class='$class'>
@@ -4992,6 +5001,87 @@ sub check_ip_acc {
     return $allowed;
 }
 
+sub check_slotip_acc {
+    my ($acc,$clientip)=@_;
+    &Apache::lonxml::debug("acc is $acc");
+    if (!defined($acc) || $acc =~ /^\s*$/ || $acc =~/^\s*no\s*$/i) {
+        return 1;
+    }
+    my $allowed;
+    my $ip=$ENV{'REMOTE_ADDR'} || $clientip || $env{'request.host'};
+
+    my $name;
+    my %access = (
+                     allowfrom => 1,
+                     denyfrom  => 0,
+                 );
+    my @allows;
+    my @denies;
+    foreach my $item (split(',',$acc)) {
+        $item =~ s/^\s*//;
+        $item =~ s/\s*$//;
+        my $pattern;
+        if ($item =~ /^\!(.+)$/) {
+            push(@denies,$1);
+        } else {
+            push(@allows,$item);
+        }
+   }
+   my $numdenies = scalar(@denies);
+   my $numallows = scalar(@allows);
+   my $count = 0;
+   foreach my $pattern (@denies,@allows) {
+        $count ++;
+        my $acctype = 'allowfrom';
+        if ($count <= $numdenies) {
+            $acctype = 'denyfrom';
+        }
+        if ($pattern =~ /\*$/) {
+            #35.8.*
+            $pattern=~s/\*//;
+            if ($ip =~ /^\Q$pattern\E/) { $allowed=$access{$acctype}; }
+        } elsif ($pattern =~ /(\d+\.\d+\.\d+)\.\[(\d+)-(\d+)\]$/) {
+            #35.8.3.[34-56]
+            my $low=$2;
+            my $high=$3;
+            $pattern=$1;
+            if ($ip =~ /^\Q$pattern\E/) {
+                my $last=(split(/\./,$ip))[3];
+                if ($last <=$high && $last >=$low) { $allowed=$access{$acctype}; }
+            }
+        } elsif ($pattern =~ /^\*/) {
+            #*.msu.edu
+            $pattern=~s/\*//;
+            if (!defined($name)) {
+                use Socket;
+                my $netaddr=inet_aton($ip);
+                ($name)=gethostbyaddr($netaddr,AF_INET);
+            }
+            if ($name =~ /\Q$pattern\E$/i) { $allowed=$access{$acctype}; }
+        } elsif ($pattern =~ /\d+\.\d+\.\d+\.\d+/) {
+            #127.0.0.1
+            if ($ip =~ /^\Q$pattern\E/) { $allowed=$access{$acctype}; }
+        } else {
+            #some.name.com
+            if (!defined($name)) {
+                use Socket;
+                my $netaddr=inet_aton($ip);
+                ($name)=gethostbyaddr($netaddr,AF_INET);
+            }
+            if ($name =~ /\Q$pattern\E$/i) { $allowed=$access{$acctype}; }
+        }
+        if ($allowed =~ /^(0|1)$/) { last; }
+    }
+    if ($allowed eq '') {
+        if ($numdenies && !$numallows) {
+            $allowed = 1;
+        } else {
+            $allowed = 0;
+        }
+    }
+    return $allowed;
+}
+
 ###############################################
 
 =pod
@@ -5132,7 +5222,7 @@ sub get_legacy_domconf {
     my $designdir=$Apache::lonnet::perlvar{'lonTabDir'}.'/lonDomColors';
     my $designfile =  $designdir.'/'.$udom.'.tab';
     if (-e $designfile) {
-        if ( open (my $fh,"<$designfile") ) {
+        if ( open (my $fh,'<',$designfile) ) {
             while (my $line = <$fh>) {
                 next if ($line =~ /^\#/);
                 chomp($line);
@@ -7897,6 +7987,7 @@ OFFLOAD
 <meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=0, minimum-scale=1.0, maximum-scale=1.0">
 <meta name="apple-mobile-web-app-capable" content="yes" />';
     }
+    $result .= '<meta name="google" content="notranslate" />'."\n";
     return $result.'</head>';
 }
 
@@ -9574,7 +9665,7 @@ sub get_secgrprole_info {
 }
 
 sub user_picker {
-    my ($dom,$srch,$forcenewuser,$caller,$cancreate,$usertype,$context,$fixeddom) = @_;
+    my ($dom,$srch,$forcenewuser,$caller,$cancreate,$usertype,$context,$fixeddom,$noinstd) = @_;
     my $currdom = $dom;
     my @alldoms = &Apache::lonnet::all_domains();
     if (@alldoms == 1) {
@@ -9639,10 +9730,12 @@ sub user_picker {
     &html_escape(\%html_lt);
     &js_escape(\%js_lt);
     my $domform;
+    my $allow_blank = 1;
     if ($fixeddom) {
-        $domform = &select_dom_form($currdom,'srchdomain',1,1,undef,[$currdom]);
+        $allow_blank = 0;
+        $domform = &select_dom_form($currdom,'srchdomain',$allow_blank,1,undef,[$currdom]);
     } else {
-        $domform = &select_dom_form($currdom,'srchdomain',1,1);
+        $domform = &select_dom_form($currdom,'srchdomain',$allow_blank,1);
     }
     my $srchinsel = ' <select name="srchin">';
 
@@ -9655,6 +9748,7 @@ sub user_picker {
         next if ($option eq 'alc');
         next if (($option eq 'crs') && ($env{'form.form'} eq 'requestcrs'));  
         next if ($option eq 'crs' && !$env{'request.course.id'});
+        next if (($option eq 'instd') && ($noinstd));
         if ($curr_selected{'srchin'} eq $option) {
             $srchinsel .= ' 
    <option value="'.$option.'" selected="selected">'.$html_lt{$option}.'</option>';
@@ -11416,7 +11510,7 @@ sub modify_html_refs {
                 return;
             }
         } 
-        if (open(my $fh,"<$container")) {
+        if (open(my $fh,'<',$container)) {
             $content = join('', <$fh>);
             close($fh);
         } else {
@@ -11481,7 +11575,7 @@ sub modify_html_refs {
                         }
                     }
                 } else {
-                    if (open(my $fh,">$container")) {
+                    if (open(my $fh,'>',$container)) {
                         print $fh $content;
                         close($fh);
                         $output = '<p>'.&mt('Updated [quant,_1,reference] in [_2].',
@@ -11998,6 +12092,18 @@ sub decompress_uploaded_file {
 
 sub process_decompression {
     my ($docudom,$docuname,$file,$destination,$dir_root,$hiddenelem) = @_;
+    unless (($dir_root eq '/userfiles') && ($destination =~ m{^(docs|supplemental)/(default|\d+)/\d+$})) {
+        return '<p class="LC_error">'.&mt('Not extracted.').'<br />'.
+               &mt('Unexpected file path.').'</p>'."\n";
+    }
+    unless (($docudom =~ /^$match_domain$/) && ($docuname =~ /^$match_courseid$/)) {
+        return '<p class="LC_error">'.&mt('Not extracted.').'<br />'.
+               &mt('Unexpected course context.').'</p>'."\n";
+    }
+    unless ($file eq &Apache::lonnet::clean_filename($file)) {
+        return '<p class="LC_error">'.&mt('Not extracted.').'<br />'.
+               &mt('Filename contained unexpected characters.').'</p>'."\n";
+    }
     my ($dir,$error,$warning,$output);
     if ($file !~ /\.(zip|tar|bz2|gz|tar.gz|tar.bz2|tgz)$/i) {
         $error = &mt('Filename not a supported archive file type.').
@@ -12032,30 +12138,44 @@ sub process_decompression {
                 }
             }
             my $numskip = scalar(@to_skip);
-            if (($numskip > 0) && 
-                ($numskip == $env{'form.archive_itemcount'})) {
+            my $numoverwrite = scalar(@to_overwrite);
+            if (($numskip) && (!$numoverwrite)) {
                 $warning = &mt('All items in the archive file already exist, and no overwriting of existing files has been requested.');         
             } elsif ($dir eq '') {
                 $error = &mt('Directory containing archive file unavailable.');
             } elsif (!$error) {
                 my ($decompressed,$display);
-                if ($numskip > 0) {
+                if (($numskip) || ($numoverwrite)) {
                     my $tempdir = time.'_'.$$.int(rand(10000));
                     mkdir("$dir/$tempdir",0755);
-                    system("mv $dir/$file $dir/$tempdir/$file");
-                    ($decompressed,$display) = 
-                        &decompress_uploaded_file($file,"$dir/$tempdir");
-                    foreach my $item (@to_skip) {
-                        if (($item ne '') && ($item !~ /\.\./)) {
-                            if (-f "$dir/$tempdir/$item") { 
-                                unlink("$dir/$tempdir/$item");
-                            } elsif (-d "$dir/$tempdir/$item") {
-                                system("rm -rf $dir/$tempdir/$item");
+                    if (&File::Copy::move("$dir/$file","$dir/$tempdir/$file")) {
+                        ($decompressed,$display) =
+                            &decompress_uploaded_file($file,"$dir/$tempdir");
+                        foreach my $item (@to_skip) {
+                            if (($item ne '') && ($item !~ /\.\./)) {
+                                if (-f "$dir/$tempdir/$item") {
+                                    unlink("$dir/$tempdir/$item");
+                                } elsif (-d "$dir/$tempdir/$item") {
+                                    &File::Path::remove_tree("$dir/$tempdir/$item",{ safe => 1 });
+                                }
+                            }
+                        }
+                        foreach my $item (@to_overwrite) {
+                            if ((-e "$dir/$tempdir/$item") && (-e "$dir/$item")) {
+                                if (($item ne '') && ($item !~ /\.\./)) {
+                                    if (-f "$dir/$item") {
+                                        unlink("$dir/$item");
+                                    } elsif (-d "$dir/$item") {
+                                        &File::Path::remove_tree("$dir/$item",{ safe => 1 });
+                                    }
+                                    &File::Copy::move("$dir/$tempdir/$item","$dir/$item");
+                                }
                             }
                         }
+                        if (&File::Copy::move("$dir/$tempdir/$file","$dir/$file")) {
+                            &File::Path::remove_tree("$dir/$tempdir",{ safe => 1 });
+                        }
                     }
-                    system("mv $dir/$tempdir/* $dir");
-                    rmdir("$dir/$tempdir");   
                 } else {
                     ($decompressed,$display) = 
                         &decompress_uploaded_file($file,$dir);
@@ -12559,7 +12679,7 @@ END
 sub process_extracted_files {
     my ($context,$docudom,$docuname,$destination,$dir_root,$hiddenelem) = @_;
     my $numitems = $env{'form.archive_count'};
-    return unless ($numitems);
+    return if ((!$numitems) || ($numitems =~ /\D/));
     my @ids=&Apache::lonnet::current_machine_ids();
     my ($prefix,$pathtocheck,$dir,$ishome,$error,$warning,%toplevelitems,%is_dir,
         %folders,%containers,%mapinner,%prompttofetch);
@@ -12572,7 +12692,7 @@ sub process_extracted_files {
     } else {
         $prefix = $Apache::lonnet::perlvar{'lonDocRoot'};
         $pathtocheck = "$dir_root/$docudom/$docuname/$destination";
-        $dir = "$dir_root/$docudom/$docuname";    
+        $dir = "$dir_root/$docudom/$docuname";
     }
     my $currdir = "$dir_root/$destination";
     (my $docstype,$mapinner{'0'}) = ($destination =~ m{^(docs|supplemental)/(\w+)/});
@@ -12661,7 +12781,9 @@ sub process_extracted_files {
                                                         '.'.$containers{$outer},1,1);
                             $newseqid{$i} = $newidx;
                             unless ($errtext) {
-                                $result .=  '<li>'.&mt('Folder: [_1] added to course',$docstitle).'</li>'."\n";
+                                $result .=  '<li>'.&mt('Folder: [_1] added to course',
+                                                       &HTML::Entities::encode($docstitle,'<>&"')).
+                                            '</li>'."\n";
                             }
                         }
                     } else {
@@ -12670,38 +12792,47 @@ sub process_extracted_files {
                             my $url = '/uploaded/'.$docudom.'/'.$docuname.'/'.
                                       $docstype.'/'.$mapinner{$outer}.'/'.$newidx.'/'.
                                       $title;
-                            if (!-e "$prefix$dir/$docstype/$mapinner{$outer}") {
-                                mkdir("$prefix$dir/$docstype/$mapinner{$outer}",0755);
-                            }
-                            if (!-e "$prefix$dir/$docstype/$mapinner{$outer}/$newidx") {
-                                mkdir("$prefix$dir/$docstype/$mapinner{$outer}/$newidx");
-                            }
-                            if (-e "$prefix$dir/$docstype/$mapinner{$outer}/$newidx") {
-                                system("mv $prefix$path $prefix$dir/$docstype/$mapinner{$outer}/$newidx/$title");
-                                $newdest{$i} = "$prefix$dir/$docstype/$mapinner{$outer}/$newidx";
-                                unless ($ishome) {
-                                    my $fetch = "$newdest{$i}/$title";
-                                    $fetch =~ s/^\Q$prefix$dir\E//;
-                                    $prompttofetch{$fetch} = 1;
+                            if (($outer !~ /\D/) && ($mapinner{$outer} !~ /\D/) && ($newidx !~ /\D/)) {
+                                if (!-e "$prefix$dir/$docstype/$mapinner{$outer}") {
+                                    mkdir("$prefix$dir/$docstype/$mapinner{$outer}",0755);
                                 }
-                            }
-                            $LONCAPA::map::resources[$newidx]=
-                                $docstitle.':'.$url.':false:normal:res';
-                            push(@LONCAPA::map::order, $newidx);
-                            my ($outtext,$errtext)=
-                                &LONCAPA::map::storemap('/uploaded/'.$docudom.'/'.
-                                                        $docuname.'/'.$folders{$outer}.
-                                                        '.'.$containers{$outer},1,1);
-                            unless ($errtext) {
-                                if (-e "$prefix$dir/$docstype/$mapinner{$outer}/$newidx/$title") {
-                                    $result .= '<li>'.&mt('File: [_1] added to course',$docstitle).'</li>'."\n";
+                                if (!-e "$prefix$dir/$docstype/$mapinner{$outer}/$newidx") {
+                                    mkdir("$prefix$dir/$docstype/$mapinner{$outer}/$newidx");
                                 }
+                                if (-e "$prefix$dir/$docstype/$mapinner{$outer}/$newidx") {
+                                    if (rename("$prefix$path","$prefix$dir/$docstype/$mapinner{$outer}/$newidx/$title")) {
+                                        $newdest{$i} = "$prefix$dir/$docstype/$mapinner{$outer}/$newidx";
+                                        unless ($ishome) {
+                                            my $fetch = "$newdest{$i}/$title";
+                                            $fetch =~ s/^\Q$prefix$dir\E//;
+                                            $prompttofetch{$fetch} = 1;
+                                        }
+                                    }
+                                }
+                                $LONCAPA::map::resources[$newidx]=
+                                    $docstitle.':'.$url.':false:normal:res';
+                                push(@LONCAPA::map::order, $newidx);
+                                my ($outtext,$errtext)=
+                                    &LONCAPA::map::storemap('/uploaded/'.$docudom.'/'.
+                                                            $docuname.'/'.$folders{$outer}.
+                                                            '.'.$containers{$outer},1,1);
+                                unless ($errtext) {
+                                    if (-e "$prefix$dir/$docstype/$mapinner{$outer}/$newidx/$title") {
+                                        $result .= '<li>'.&mt('File: [_1] added to course',
+                                                              &HTML::Entities::encode($docstitle,'<>&"')).
+                                                   '</li>'."\n";
+                                    }
+                                }
+                            } else {
+                                $warning .= &mt('Item extracted from archive: [_1] has unexpected path.',
+                                                &HTML::Entities::encode($path,'<>&"')).'<br />';
                             }
                         }
                     }
                 }
             } else {
-                $warning .= &mt('Item extracted from archive: [_1] has unexpected path.',$path).'<br />';
+                $warning .= &mt('Item extracted from archive: [_1] has unexpected path.',
+                                &HTML::Entities::encode($path,'<>&"')).'<br />';
             }
         }
         for (my $i=1; $i<=$numitems; $i++) {
@@ -12762,7 +12893,9 @@ sub process_extracted_files {
                         }
                         if ($fullpath ne '') {
                             if (-e "$prefix$path") {
-                                system("mv $prefix$path $fullpath/$title");
+                                unless (rename("$prefix$path","$fullpath/$title")) {
+                                     $warning .= &mt('Failed to rename dependency').'<br />';
+                                }
                             }
                             if (-e "$fullpath/$title") {
                                 my $showpath;
@@ -12771,7 +12904,9 @@ sub process_extracted_files {
                                 } else {
                                     $showpath = "/$title";
                                 }
-                                $result .= '<li>'.&mt('[_1] included as a dependency',$showpath).'</li>'."\n";
+                                $result .= '<li>'.&mt('[_1] included as a dependency',
+                                                      &HTML::Entities::encode($showpath,'<>&"')).
+                                           '</li>'."\n";
                             }
                             unless ($ishome) {
                                 my $fetch = "$fullpath/$title";
@@ -12782,10 +12917,13 @@ sub process_extracted_files {
                     }
                 } elsif ($env{'form.archive_'.$referrer{$i}} eq 'discard') {
                     $warning .= &mt('[_1] is a dependency of [_2], which was discarded.',
-                                    $path,$env{'form.archive_content_'.$referrer{$i}}).'<br />';
+                                    &HTML::Entities::encode($path,'<>&"'),
+                                    &HTML::Entities::encode($env{'form.archive_content_'.$referrer{$i}},'<>&"')).
+                                '<br />';
                 }
             } else {
-                $warning .= &mt('Item extracted from archive: [_1] has unexpected path.',$path).'<br />';
+                $warning .= &mt('Item extracted from archive: [_1] has unexpected path.',
+                                &HTML::Entities::encode($path)).'<br />';
             }
         }
         if (keys(%todelete)) {
@@ -13059,12 +13197,14 @@ sub upfile_store {
     $env{'form.upfile'}=~s/\n+/\n/gs;
     $env{'form.upfile'}=~s/\n+$//gs;
 
-    my $datatoken=$env{'user.name'}.'_'.$env{'user.domain'}.
-	'_enroll_'.$env{'request.course.id'}.'_'.time.'_'.$$;
+    my $datatoken = &valid_datatoken($env{'user.name'}.'_'.$env{'user.domain'}.
+	                             '_enroll_'.$env{'request.course.id'}.'_'.
+                                     time.'_'.$$);
+    return if ($datatoken eq '');
     {
         my $datafile = $r->dir_config('lonDaemons').
                            '/tmp/'.$datatoken.'.tmp';
-        if ( open(my $fh,">$datafile") ) {
+        if ( open(my $fh,'>',$datafile) ) {
             print $fh $env{'form.upfile'};
             close($fh);
         }
@@ -13074,21 +13214,22 @@ sub upfile_store {
 
 =pod
 
-=item * &load_tmp_file($r)
+=item * &load_tmp_file($r,$datatoken)
 
 Load uploaded file from tmp, $r should be the HTTP Request object,
-needs $env{'form.datatoken'},
+$datatoken is the name to assign to the temporary file.
 sets $env{'form.upfile'} to the contents of the file
 
 =cut
 
 sub load_tmp_file {
-    my $r=shift;
+    my ($r,$datatoken) = @_;
+    return if ($datatoken eq '');
     my @studentdata=();
     {
         my $studentfile = $r->dir_config('lonDaemons').
-                              '/tmp/'.$env{'form.datatoken'}.'.tmp';
-        if ( open(my $fh,"<$studentfile") ) {
+                              '/tmp/'.$datatoken.'.tmp';
+        if ( open(my $fh,'<',$studentfile) ) {
             @studentdata=<$fh>;
             close($fh);
         }
@@ -13096,6 +13237,14 @@ sub load_tmp_file {
     $env{'form.upfile'}=join('',@studentdata);
 }
 
+sub valid_datatoken {
+    my ($datatoken) = @_;
+    if ($datatoken =~ /^$match_username\_$match_domain\_enroll_(|$match_domain\_$match_courseid)\_\d+_\d+$/) {
+        return $datatoken;
+    }
+    return;
+}
+
 =pod
 
 =item * &upfile_record_sep()
@@ -13984,6 +14133,13 @@ defdom (domain for which to retrieve con
 origmail (scalar - email address of recipient from loncapa.conf,
 i.e., predates configuration by DC via domainprefs.pm
 
+$requname username of requester (if mailing type is helpdeskmail)
+
+$requdom domain of requester (if mailing type is helpdeskmail)
+
+$reqemail e-mail address of requester (if mailing type is helpdeskmail)
+
+
 Returns: comma separated list of addresses to which to send e-mail.
 
 =back
@@ -13993,7 +14149,7 @@ Returns: comma separated list of address
 ############################################################
 ############################################################
 sub build_recipient_list {
-    my ($defmail,$mailing,$defdom,$origmail) = @_;
+    my ($defmail,$mailing,$defdom,$origmail,$requname,$requdom,$reqemail) = @_;
     my @recipients;
     my ($otheremails,$lastresort,$allbcc,$addtext);
     my %domconfig =
@@ -14034,11 +14190,99 @@ sub build_recipient_list {
         } elsif ($origmail ne '') {
             $lastresort = $origmail;
         }
+        if ($mailing eq 'helpdeskmail') {
+            if ((ref($domconfig{'contacts'}{'overrides'}) eq 'HASH') &&
+                (keys(%{$domconfig{'contacts'}{'overrides'}}))) {
+                my ($inststatus,$inststatus_checked);
+                if (($env{'user.name'} ne '') && ($env{'user.domain'} ne '') &&
+                    ($env{'user.domain'} ne 'public')) {
+                    $inststatus_checked = 1;
+                    $inststatus = $env{'environment.inststatus'};
+                }
+                unless ($inststatus_checked) {
+                    if (($requname ne '') && ($requdom ne '')) {
+                        if (($requname =~ /^$match_username$/) &&
+                            ($requdom =~ /^$match_domain$/) &&
+                            (&Apache::lonnet::domain($requdom))) {
+                            my $requhome = &Apache::lonnet::homeserver($requname,
+                                                                      $requdom);
+                            unless ($requhome eq 'no_host') {
+                                my %userenv = &Apache::lonnet::userenvironment($requdom,$requname,'inststatus');
+                                $inststatus = $userenv{'inststatus'};
+                                $inststatus_checked = 1;
+                            }
+                        }
+                    }
+                }
+                unless ($inststatus_checked) {
+                    if ($reqemail =~ /^[^\@]+\@[^\@]+$/) {
+                        my %srch = (srchby     => 'email',
+                                    srchdomain => $defdom,
+                                    srchterm   => $reqemail,
+                                    srchtype   => 'exact');
+                        my %srch_results = &Apache::lonnet::usersearch(\%srch);
+                        foreach my $uname (keys(%srch_results)) {
+                            if (ref($srch_results{$uname}{'inststatus'}) eq 'ARRAY') {
+                                $inststatus = join(',',@{$srch_results{$uname}{'inststatus'}});
+                                $inststatus_checked = 1;
+                                last;
+                            }
+                        }
+                        unless ($inststatus_checked) {
+                            my ($dirsrchres,%srch_results) = &Apache::lonnet::inst_directory_query(\%srch);
+                            if ($dirsrchres eq 'ok') {
+                                foreach my $uname (keys(%srch_results)) {
+                                    if (ref($srch_results{$uname}{'inststatus'}) eq 'ARRAY') {
+                                        $inststatus = join(',',@{$srch_results{$uname}{'inststatus'}});
+                                        $inststatus_checked = 1;
+                                        last;
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+                if ($inststatus ne '') {
+                    foreach my $status (split(/\:/,$inststatus)) {
+                        if (ref($domconfig{'contacts'}{'overrides'}{$status}) eq 'HASH') {
+                            my @contacts = ('adminemail','supportemail');
+                            foreach my $item (@contacts) {
+                                if ($domconfig{'contacts'}{'overrides'}{$status}{$item}) {
+                                    my $addr = $domconfig{'contacts'}{'overrides'}{$status};
+                                    if (!grep(/^\Q$addr\E$/,@recipients)) {
+                                        push(@recipients,$addr);
+                                    }
+                                }
+                            }
+                            $otheremails = $domconfig{'contacts'}{'overrides'}{$status}{'others'};
+                            if ($domconfig{'contacts'}{'overrides'}{$status}{'bcc'}) {
+                                my @bccs = split(/,/,$domconfig{'contacts'}{'overrides'}{$status}{'bcc'});
+                                my @ok_bccs;
+                                foreach my $bcc (@bccs) {
+                                    $bcc =~ s/^\s+//g;
+                                    $bcc =~ s/\s+$//g;
+                                    if ($bcc =~ m/^[^\@]+\@[^\@]+$/) {
+                                        if (!(grep(/^\Q$bcc\E$/,@ok_bccs))) {
+                                            push(@ok_bccs,$bcc);
+                                        }
+                                    }
+                                }
+                                if (@ok_bccs > 0) {
+                                    $allbcc = join(', ',@ok_bccs);
+                                }
+                            }
+                            $addtext = $domconfig{'contacts'}{'overrides'}{$status}{'include'};
+                            last;
+                        }
+                    }
+                }
+            }
+        }
     } elsif ($origmail ne '') {
         $lastresort = $origmail;
     }
 
-    if (($mailing eq 'helpdesk') && ($lastresort ne '')) {
+    if (($mailing eq 'helpdeskmail') && ($lastresort ne '')) {
         unless (grep(/^\Q$defdom\E$/,&Apache::lonnet::current_machine_domains())) {
             my $lonhost = $Apache::lonnet::perlvar{'lonHostID'};
             my $machinedom = $Apache::lonnet::perlvar{'lonDefDomain'};
@@ -14118,7 +14362,7 @@ sub build_recipient_list {
             }
         }
     }
-    if ($mailing eq 'helpdesk') {
+    if ($mailing eq 'helpdeskmail') {
         if ((!@recipients) && ($lastresort ne '')) {
             push(@recipients,$lastresort);
         }
@@ -15421,8 +15665,7 @@ sub init_user_environment {
 
     my %userenv = &Apache::lonnet::dump('environment',$domain,$username);
     my ($tmp) = keys(%userenv);
-    if ($tmp !~ /^(con_lost|error|no_such_host)/i) {
-    } else {
+    if ($tmp =~ /^(con_lost|error|no_such_host)/i) {
 	undef(%userenv);
     }
     if (($userenv{'interface'}) && (!$form->{'interface'})) {
@@ -16315,8 +16558,12 @@ sub needs_coursereinit {
         $interval = 600;
     }
     if (($now-$env{'request.course.timechecked'})>$interval) {
-        my $lastchange = &Apache::lonnet::get_coursechange($cdom,$cnum);
         &Apache::lonnet::appenv({'request.course.timechecked'=>$now});
+        my $blocked = &blocking_status('reinit',$cnum,$cdom,undef,1);
+        if ($blocked) {
+            return ();
+        }
+        my $lastchange = &Apache::lonnet::get_coursechange($cdom,$cnum);
         if ($lastchange > $env{'request.course.tied'}) {
             my %curr_reqd_hash = &Apache::lonnet::userenvironment($cdom,$cnum,'internal.releaserequired');
             if ($curr_reqd_hash{'internal.releaserequired'} ne '') {
@@ -16751,9 +16998,25 @@ sub cleanup_html {
 
 # Checks for critical messages and returns a redirect url if one exists.
 # $interval indicates how often to check for messages.
+# $context is the calling context -- roles, grades, contents, menu or flip.
 sub critical_redirect {
-    my ($interval) = @_;
+    my ($interval,$context) = @_;
     if ((time-$env{'user.criticalcheck.time'})>$interval) {
+        if (($env{'request.course.id'}) && (($context eq 'flip') || ($context eq 'contents'))) {
+            my $cdom = $env{'course.'.$env{'request.course.id'}.'.domain'};
+            my $cnum = $env{'course.'.$env{'request.course.id'}.'.num'};
+            my $blocked = &blocking_status('alert',$cnum,$cdom,undef,1);
+            if ($blocked) {
+                my $checkrole = "cm./$cdom/$cnum";
+                if ($env{'request.course.sec'} ne '') {
+                    $checkrole .= "/$env{'request.course.sec'}";
+                }
+                unless ((&Apache::lonnet::allowed('evb',undef,undef,$checkrole)) &&
+                        ($env{'request.role'} !~ m{^st\./$cdom/$cnum})) {
+                    return;
+                }
+            }
+        }
         my @what=&Apache::lonnet::dump('critical', $env{'user.domain'},
                                         $env{'user.name'});
         &Apache::lonnet::appenv({'user.criticalcheck.time'=>time});
@@ -16819,6 +17082,142 @@ sub des_decrypt {
     return $plaintext;
 }
 
+sub make_short_symbs {
+    my ($cdom,$cnum,$navmap) = @_;
+    return unless (ref($navmap));
+    my ($numnew,@errors);
+    my @toshorten = &Apache::loncommon::get_env_multiple('form.addtiny');
+    if (@toshorten) {
+        my (%maps,%resources,%titles);
+        &Apache::loncourserespicker::enumerate_course_contents($navmap,\%maps,\%resources,\%titles,
+                                                               'shorturls',$cdom,$cnum);
+        my %tocreate;
+        if (keys(%resources)) {
+            foreach my $item (sort {$a <=> $b} (@toshorten)) {
+                my $symb = $resources{$item};
+                if ($symb) {
+                    $tocreate{$cnum.'&'.$symb} = 1;
+                }
+            }
+        }
+        if (keys(%tocreate)) {
+            my %coursetiny = &Apache::lonnet::dump('tiny',$cdom,$cnum);
+            my $su = Short::URL->new(no_vowels => 1);
+            my $init = '';
+            my (%newunique,%addcourse,%courseonly,%failed);
+            # get lock on tiny db
+            my $now = time;
+            my $lockhash = {
+                                "lock\0$now" => $env{'user.name'}.
+                                                ':'.$env{'user.domain'},
+                            };
+            my $tries = 0;
+            my $gotlock = &Apache::lonnet::newput_dom('tiny',$lockhash,$cdom);
+            my ($code,$error);
+            while (($gotlock ne 'ok') && ($tries<3)) {
+                $tries ++;
+                sleep 1;
+                $gotlock = &Apache::lonnet::newput_dom('tiny',$lockhash,$cdom);
+            }
+            if ($gotlock eq 'ok') {
+                $init = &shorten_symbs($cdom,$init,$su,\%coursetiny,\%tocreate,\%newunique,
+                                       \%addcourse,\%courseonly,\%failed);
+                if (keys(%failed)) {
+                    my $numfailed = scalar(keys(%failed));
+                    push(@errors,&mt('error: could not obtain unique six character URL for [quant,_1,resource]',$numfailed));
+                }
+                if (keys(%newunique)) {
+                    my $putres = &Apache::lonnet::newput_dom('tiny',\%newunique,$cdom);
+                    if ($putres eq 'ok') {
+                        $numnew = scalar(keys(%newunique));
+                        my $newputres = &Apache::lonnet::newput('tiny',\%addcourse,$cdom,$cnum);
+                        unless ($newputres eq 'ok') {
+                            push(@errors,&mt('error: could not store course look-up of short URLs'));
+                        }
+                    } else {
+                        push(@errors,&mt('error: could not store unique six character URLs'));
+                    }
+                }
+                my $dellockres = &Apache::lonnet::del_dom('tiny',["lock\0$now"],$cdom);
+                unless ($dellockres eq 'ok') {
+                    push(@errors,&mt('error: could not release lockfile'));
+                }
+            } else {
+                push(@errors,&mt('error: could not obtain lockfile'));
+            }
+            if (keys(%courseonly)) {
+                my $result = &Apache::lonnet::newput('tiny',\%courseonly,$cdom,$cnum);
+                if ($result ne 'ok') {
+                    push(@errors,&mt('error: could not update course look-up of short URLs'));
+                }
+            }
+        }
+    }
+    return ($numnew,\@errors);
+}
+
+sub shorten_symbs {
+    my ($cdom,$init,$su,$coursetiny,$tocreate,$newunique,$addcourse,$courseonly,$failed) = @_;
+    return unless ((ref($su)) && (ref($coursetiny) eq 'HASH') && (ref($tocreate) eq 'HASH') &&
+                   (ref($newunique) eq 'HASH') && (ref($addcourse) eq 'HASH') &&
+                   (ref($courseonly) eq 'HASH') && (ref($failed) eq 'HASH'));
+    my (%possibles,%collisions);
+    foreach my $key (keys(%{$tocreate})) {
+        my $num = String::CRC32::crc32($key);
+        my $tiny = $su->encode($num,$init);
+        if ($tiny) {
+            $possibles{$tiny} = $key;
+        }
+    }
+    if (!$init) {
+        $init = 1;
+    } else {
+        $init ++;
+    }
+    if (keys(%possibles)) {
+        my @posstiny = keys(%possibles);
+        my $configuname = &Apache::lonnet::get_domainconfiguser($cdom);
+        my %currtiny = &Apache::lonnet::get('tiny',\@posstiny,$cdom,$configuname);
+        if (keys(%currtiny)) {
+            foreach my $key (keys(%currtiny)) {
+                next if ($currtiny{$key} eq '');
+                if ($currtiny{$key} eq $possibles{$key}) {
+                    my ($tcnum,$tsymb) = split(/\&/,$currtiny{$key});
+                    unless (($coursetiny->{$tsymb} eq $key) || ($addcourse->{$tsymb} eq $key) || ($courseonly->{$tsymb} eq $key)) {
+                        $courseonly->{$tsymb} = $key;
+                    }
+                } else {
+                    $collisions{$possibles{$key}} = 1;
+                }
+                delete($possibles{$key});
+            }
+        }
+        foreach my $key (keys(%possibles)) {
+            $newunique->{$key} = $possibles{$key};
+            my ($tcnum,$tsymb) = split(/\&/,$possibles{$key});
+            unless (($coursetiny->{$tsymb} eq $key) || ($addcourse->{$tsymb} eq $key) || ($courseonly->{$tsymb} eq $key)) {
+                $addcourse->{$tsymb} = $key;
+            }
+        }
+    }
+    if (keys(%collisions)) {
+        if ($init <5) {
+            if (!$init) {
+                $init = 1;
+            } else {
+                $init ++;
+            }
+            $init = &shorten_symbs($cdom,$init,$su,$coursetiny,\%collisions,
+                                   $newunique,$addcourse,$courseonly,$failed);
+        } else {
+            foreach my $key (keys(%collisions)) {
+                $failed->{$key} = 1;
+            }
+        }
+    }
+    return $init;
+}
+
 1;
 __END__;