--- doc/loncapafiles/webserver.piml	2019/02/16 14:25:20	1.43.2.1
+++ doc/loncapafiles/webserver.piml	2020/09/06 18:13:11	1.53
@@ -2,7 +2,7 @@
 	"http://lpml.sourceforge.net/DTD/piml.dtd">
 <!-- webserver.piml -->
 
-<!-- $Id: webserver.piml,v 1.43.2.1 2019/02/16 14:25:20 raeburn Exp $ -->
+<!-- $Id: webserver.piml,v 1.53 2020/09/06 18:13:11 raeburn Exp $ -->
 
 <!--
 
@@ -48,8 +48,8 @@ http://www.lon-capa.org/
 <target dist='suse9.2 suse9.3 sles9'>/etc/httpd/httpd.conf</target>
 <target dist='sles10 sles11 sles12 sles15 suse10.1 suse10.2 suse10.3 suse11.1 suse11.2 suse11.3 suse11.4 suse12.1 suse12.2 suse12.3 suse13.1 suse13.2'>/etc/apache2/default-server.conf</target>
 <target dist='debian5 debian6 ubuntu6 ubuntu8 ubuntu10 ubuntu12'>/etc/apache2/sites-available/loncapa</target>
-<target dist='ubuntu14 ubuntu16 ubuntu18'>/etc/apache2/conf-available/loncapa</target>
-<note>This is for Apache 1.X for Red Hat 4ES, Fedora 2, 3 and 4, SusSE 9.2 and 9.3, and SLES 9 distributions. This is for Apache 2.X for Fedora 5, Red Hat 5, CentOS 5, Scientific Linux 5, SuSE 10.1, SLES 10, Debian 5, Ubuntu LTS 8 and later distributions</note>
+<target dist='ubuntu14 ubuntu16 ubuntu18 ubuntu20'>/etc/apache2/conf-available/loncapa</target>
+<note>This is for Apache 1.X for Red Hat 4ES, Fedora 2, 3 and 4, SusSE 9.2 and 9.3, and SLES 9 distributions. This is for Apache 2.X for Fedora 5, Red Hat 5, CentOS 5, Scientific Linux 5, Oracle Linux 5, SuSE 10.1, SLES 10, Debian 5, Ubuntu LTS 8 and later distributions</note>
 <dependencies dist='default'>
 /etc/httpd/conf/httpd.conf
 </dependencies>
@@ -59,7 +59,7 @@ http://www.lon-capa.org/
 <dependencies dist='debian5 debian6 ubuntu6 ubuntu8 ubuntu10 ubuntu12'>
 /etc/apache2/sites-available/loncapa
 </dependencies>
-<dependencies dist='ubuntu14 ubuntu16 ubuntu18'>
+<dependencies dist='ubuntu14 ubuntu16 ubuntu18 ubuntu20'>
 /etc/apache2/conf-available/loncapa
 </dependencies>
 <dependencies dist='sles10 sles11 sles12 sles15 suse10.1 suse10.2 suse10.3 suse11.1 suse11.2 suse11.3 suse11.4 suse12.1 suse12.2 suse12.3 suse13.1 suse13.2'>
@@ -67,6 +67,8 @@ http://www.lon-capa.org/
 </dependencies>
 <perlscript mode='fg' dist="default">
 # Generated from doc/loncapafiles/webserver.piml
+use Socket;
+use Sys::Hostname::FQDN();
 unless (-e "<TARGET />") {
   print '**** ERROR! <TARGET /> should exist! Are you missing the Apache '.
     'software package?';
@@ -168,13 +170,15 @@ else {
         system("cp $rewrite_off $curr_rewrite");
         chmod(0644, $curr_rewrite);
     } else {
-        my ($not_rewrite_on,$not_rewrite_off);
+        my ($not_rewrite_on,$not_rewrite_off,$rewrite_state);
         if (open(PIPE, "diff --brief $rewrite_off $curr_rewrite |")) {
             my $diffres = &lt;PIPE&gt; ;
             close(PIPE);
             chomp($diffres);
             if ($diffres) {
                 $not_rewrite_off = 1;
+            } else {
+                $rewrite_state = 'off';
             }
         }
         if (open(PIPE, "diff --brief $rewrite_on $curr_rewrite |")) {
@@ -183,16 +187,130 @@ else {
             chomp($diffres);
             if ($diffres) {
                 $not_rewrite_on = 1;
+            } else {
+                $rewrite_state = 'on';
             }
         }
-        unless ($not_rewrite_off || $not_rewrite_on) {
-            print('**** WARNING **** '.$curr_rewrite.' does not match '.
-            'either: '.$rewrite_on.' - the file used to enable rewriting '.
-            'of requests for http:// to https:// or: '.$rewrite_off.
+        if ($not_rewrite_off && $not_rewrite_on) {
+            print('**** WARNING **** '."\n".$curr_rewrite.' does not match '.
+            'either:'."\n".$rewrite_on.' - the file used to enable rewriting '.
+            'of requests for http:// to https:// '."\n".'or:'."\n".$rewrite_off.
             ' - the file used to disable such rewriting'."\n\n".
             'This may be because '. $curr_rewrite.' has been '. 
-            'previously customized, or it may be because of a change '.  
+            'previously customized,'."\n".'or it may be because of a change '.  
             'to the files in '.$rewrite_dir."\n");
+            if (open(my $fh,'&lt;',$curr_rewrite)) {
+                while(&lt;$fh&gt;) {
+                    if (/^\s*RewriteEngine\s+(on|off)\s*$/i) {
+                        if ($1 eq 'on') {
+                            $rewrite_state = 'on';
+                        } else {
+                            $rewrite_state = 'off';
+                        }
+                        last;
+                    }
+                }
+            }
+        }
+        if ($rewrite_state eq 'on') {
+        # Checking for rewrites of https:// to http://
+            my ($gotrules,$rulestr,$ssldir);
+            if ('<DIST />' eq 'suse9.2' || '<DIST />' eq 'suse9.3'
+                || '<DIST />' eq 'sles9') {
+                $ssldir = '/etc/apache/vhosts.d';
+            } elsif ('<DIST />' =~ /^(suse|sles)/) {
+                $ssldir = '/etc/apache2/vhosts.d';
+            } elsif ('<DIST />' =~ /^(debian|ubuntu)/) {
+                $ssldir = '/etc/apache2/sites-available';
+            } else {
+                $ssldir = '/etc/httpd/conf.d';
+            }
+            my $hostname = Sys::Hostname::FQDN::fqdn();
+            my $hostip = Socket::inet_ntoa(scalar(gethostbyname($hostname)) || 'localhost');
+            my @expected = ('RewriteEngine on',
+                            'RewriteCond %{HTTPS} =on',
+                            'RewriteCond %{REQUEST_URI} ^/adm/wrapper/ext/(?!https:)',
+                            'RewriteCond %{QUERY_STRING} (^|&(|amp;))usehttp=1($|&)',
+                            'RewriteRule ^/adm/wrapper/ext/(?!https:) http://%{HTTP_HOST}%{REQUEST_URI} [R,L,NE]',
+                            'RewriteCond %{REMOTE_ADDR} 127.0.0.1',
+                            'RewriteRule (.*) - [L]');
+            if (($hostip ne '') && ($hostip ne '127.0.0.1')) {
+                push(@expected,('RewriteCond %{REMOTE_ADDR} '.$hostip,
+                                'RewriteRule (.*) - [L]'));
+            }
+            push(@expected,('RewriteCond %{REQUEST_URI} ^/public/.*/syllabus$',
+                            'RewriteCond %{QUERY_STRING} (^|&(|amp;))usehttp=1($|&)',
+                            'RewriteRule ^/public/.*/syllabus$ http://%{HTTP_HOST}%{REQUEST_URI} [R,L,NE]'));
+            if (-d $ssldir) {
+                my @rewrites;
+                if (opendir(my $dir,$ssldir)) {
+                    my @sslconf_files;
+                    foreach my $file (!grep(/^\.$/,readdir($dir))) {
+                        if (open(my $fh,'&lt;',"$ssldir/$file")) {
+                            while (&lt;$fh&gt;) {
+                                if (/^\s*&lt;VirtualHost\s+[^:]*\:443&gt;\s*$/) {
+                                    push(@sslconf_files,$file);
+                                    last;
+                                }
+                            }
+                            close($fh);
+                        }
+                    }
+                    if (@sslconf_files) {
+                        my @rewrites;
+                        foreach my $file (@sslconf_files) {
+                            if (open(my $fh,'&lt;',"$ssldir/$file")) {
+                                my ($rewrite,$num) = (0,0);
+                                while (&lt;$fh&gt;) {
+                                    if ($rewrite) {
+                                        if (/\s*&lt;\/IfModule&gt;/) {
+                                            $rewrite = 0;
+                                            $num ++;
+                                        } else {
+                                            chomp();
+                                            s/^(\s+|\s+)$//g;
+                                            push(@{$rewrites[$num]},$_);
+                                        }
+                                    } elsif (/^\s*&lt;IfModule\s+mod_rewrite.c&gt;/) {
+                                        $rewrite = 1;
+                                    }
+                                }
+                                close($fh);
+                            }
+                        }
+                    }
+                    closedir($dir);
+                }
+                if (@rewrites) {
+                    foreach my $item (@rewrites) {
+                        if (ref($item) eq 'ARRAY') {
+                            my $found = 0;
+                            foreach my $line (@{$item}) {
+                                foreach my $match (@expected) {
+                                    if ($match eq $line) {
+                                        $found ++;
+                                        last;
+                                    }
+                                }
+                            }
+                            if ($found &gt;= @expected) {
+                                $gotrules = 1;
+                                last;
+                            }
+                        }
+                    }
+                }
+            }
+            unless ($gotrules) {
+                print('**** WARNING **** '."\n".$curr_rewrite.' is currently set so rewrites '.
+                      'of http to https are enabled for most URLs.'."\n".
+                      'Unless your Apache configuration includes Strict-Transport-Security '.
+                      '(with max-age > 0), it is recommended to also set rewrites from https to http '.
+                      'for specific URLs in a file in '.$ssldir.' by including the following:'."\n".
+                      "&lt;IfModule mod_rewrite.c&gt;\n".'  '.
+                      join("\n  ",@expected)."\n".
+                      "&lt;/IfModule&gt;\n");
+            }
         }
     }
 }