--- loncom/interface/lonmsgdisplay.pm	2020/11/11 22:04:25	1.181.2.7
+++ loncom/interface/lonmsgdisplay.pm	2023/09/15 22:32:46	1.200
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Routines for messaging display
 #
-# $Id: lonmsgdisplay.pm,v 1.181.2.7 2020/11/11 22:04:25 raeburn Exp $
+# $Id: lonmsgdisplay.pm,v 1.200 2023/09/15 22:32:46 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -111,6 +111,7 @@ use Apache::loncommunicate;
 use Apache::lonfeedback;
 use Apache::lonrss();
 use Apache::lonselstudent();
+use Apache::lonenc();
 use lib '/home/httpd/lib/perl/';
 use LONCAPA qw(:DEFAULT :match);
 
@@ -791,11 +792,11 @@ sub groupmail_header {
             ({text=>&mt('Group').": $description",
               no_mt=>1,});
     }
-    &Apache::lonhtmlcommon::add_breadcrumb
-         ({href=>"/adm/email?compose=group&group=".
-                 "$env{'form.group'}&$refarg",
-           text=>"Send a Message in a Group",
-           title=>"Compose Group Message"},);
+    &Apache::lonhtmlcommon::add_breadcrumb   
+          ({href=>"/adm/email?compose=group&group=".
+                     "$env{'form.group'}&$refarg",
+               text=>"Send a Message in a Group",
+               title=>"Compose Group Message"},);
     if ($action eq 'sending') {
             &Apache::lonhtmlcommon::add_breadcrumb
                          ({text=>"Messages being sent.",
@@ -912,7 +913,7 @@ sub discrit {
 }
 
 sub sortedmessages {
-    my ($blocked,$startblock,$endblock,$numblocked,$folder,$msgstatus) = @_;
+    my ($blocked,$startblock,$endblock,$by_ip,$numblocked,$folder,$msgstatus) = @_;
     my $suffix=&Apache::lonmsg::foldersuffix($folder);
     my @messages = &Apache::lonnet::getkeys('nohist_email'.$suffix);
     #unpack the varibles and repack into temp for sorting
@@ -944,7 +945,8 @@ sub sortedmessages {
 	    push(@temp1,$content{'recuser'},$content{'recdomain'});
 	}
         # Check whether message was sent during blocking period.
-        if ($sendtime >= $startblock && ($sendtime <= $endblock && $endblock > 0) ) {
+        if (($by_ip) ||
+            (($sendtime >= $startblock) && ($sendtime <= $endblock && $endblock > 0))) {
             $$blocked{$msgid} = 'ON';
             $$numblocked ++;
         } else { 
@@ -1071,7 +1073,9 @@ sub disfolder {
     my %blocked = ();
     my %setters = ();
     my $numblocked = 0;
-    my ($startblock,$endblock) = &Apache::loncommon::blockcheck(\%setters,'com');
+    my $clientip = &Apache::lonnet::get_requestor_ip($r);
+    my ($startblock,$endblock,$triggerblock,$by_ip,$blockdom) =
+        &Apache::loncommon::blockcheck(\%setters,'com',$clientip);
     my %js_lt = &Apache::lonlocal::texthash(
                       sede => 'Select a destination folder to which the messages will be moved.',
                       nome => 'No messages have been selected to apply this action to.',
@@ -1115,7 +1119,7 @@ sub disfolder {
 ENDDISHEADER
 
     my $fsqs='&amp;folder='.$folder;
-    my @temp=&sortedmessages(\%blocked,$startblock,$endblock,\$numblocked,$folder,$msgstatus);
+    my @temp=&sortedmessages(\%blocked,$startblock,$endblock,$by_ip,\$numblocked,$folder,$msgstatus);
     my $totalnumber=$#temp+1;
     if ($totalnumber < 1) {
         $r->print('<p class="LC_info">');
@@ -1128,7 +1132,7 @@ ENDDISHEADER
         }
         $r->print('</p>');
         if ($numblocked > 0) {
-            $r->print(&blocked_in_folder($numblocked,$startblock,$endblock,
+            $r->print(&blocked_in_folder($numblocked,$startblock,$endblock,$by_ip,$clientip,$blockdom,
                                          \%setters));
         }
         return;
@@ -1318,20 +1322,26 @@ ENDDISHEADER
     $r->print('<input type="hidden" name="folder" value="'.$folder.'" /><input type="hidden" name="startdis" value="'.$postedstartdis.'" /><input type="hidden" name="interdis" value="'.$env{'form.interdis'}.'" /><input type="hidden" name="msgstatus" value="'.$msgstatus.'" /><input type="hidden" name="markedaction" value="" /></form>');
     if ($numblocked > 0) {
         $r->print(&blocked_in_folder($numblocked,$startblock,$endblock,
-                                     \%setters));
+                                     $by_ip,$clientip,$blockdom,\%setters));
     }
 }
 
 sub blocked_in_folder {
-    my ($numblocked,$startblock,$endblock,$setters) = @_;
-    my $beginblock = &Apache::lonlocal::locallocaltime($startblock);
-    my $finishblock = &Apache::lonlocal::locallocaltime($endblock);
-    my $output = '<br /><br />'.
+    my ($numblocked,$startblock,$endblock,$by_ip,$clientip,$blockdom,$setters) = @_;
+    my $output;
+    if ($by_ip) {
+        $output = '<br /><br />'.
+                  &mt('[quant,_1,message is, messages are] not viewable because display of LON-CAPA messages is blocked for your current IP address: [_2].',$numblocked,$clientip).'<br />'.
+                  &mt('Note: communication is being blocked for certain IP address(es).');
+    } else {
+        my $beginblock = &Apache::lonlocal::locallocaltime($startblock);
+        my $finishblock = &Apache::lonlocal::locallocaltime($endblock);
+        $output = '<br /><br />'.
                   &mt('[quant,_1,message is, messages are] not viewable because display of LON-CAPA messages sent to you by other students between [_2] and [_3] is currently being blocked because of online exams.',$numblocked,$beginblock,$finishblock);
+    }
     #$output .= &Apache::loncommon::build_block_table($startblock,$endblock,
     #                                                 $setters);
-    
-    my ($blocked, $blocktext) = &Apache::loncommon::blocking_status("com");
+    my ($blocked, $blocktext) = &Apache::loncommon::blocking_status("com",$clientip);
     $output .="<br /><br />".$blocktext;
 
     return $output;
@@ -1342,6 +1352,26 @@ sub blocked_in_folder {
 sub compout {
     my ($r,$forwarding,$replying,$broadcast,$replycrit,$folder,$dismode,
         $multiforward)=@_;
+    my $clientip = &Apache::lonnet::get_requestor_ip($r);
+    my %setters;
+    my ($startblock,$endblock,$triggerblock,$by_ip,$blockdom) =
+        &Apache::loncommon::blockcheck(\%setters,'com',$clientip);
+    if ($by_ip) {
+        my $showdom = &Apache::lonnet::domain($blockdom);
+        if ($showdom eq '') {
+            $showdom = $blockdom;
+        }
+        $r->print(&Apache::loncommon::start_page('Messages'));
+        $r->print(&Apache::lonhtmlcommon::breadcrumbs('Send and display messages'));
+        $r->print('<p class="LC_warning">'.
+                 &mt('Sending of LON-CAPA messages is blocked for your current IP address: [_1].',$clientip).'</p>'.
+                 '<ul><li>'.
+                 &mt('Note: communication is being blocked for certain IP address(es).').
+                 '</li><li>'.
+                 &mt('This restriction was set by an administrator in the [_1] LON-CAPA domain.',$showdom).
+                 '</li></ul>');
+        return;
+    }
     my $suffix=&Apache::lonmsg::foldersuffix($folder);
     my ($cdom,$cnum,$group,$refarg);
     if (exists($env{'form.group'})) {
@@ -1421,7 +1451,7 @@ sub compout {
                     );
     if (!$forwarding && !$multiforward) {
         $attachrow = '<tr><td colspan="3"><b>'.$lt{'atta'}.'</b> '.$attachmax{'text'}
-            .': <input type="file" name="attachment" class="LC_flUpload" />'
+            .': <input type="file" name="attachment" class="LC_flUpload" multiple />'
             .'<input type="hidden" id="LC_free_space" value="'.$attachmax{'num'}.'" />'
             .'</td></tr>';
     }
@@ -2106,14 +2136,16 @@ sub displaymessage {
     my %setters = ();
     my $numblocked = 0;
     my $crstype = &Apache::loncommon::course_type();
+    my $clientip = &Apache::lonnet::get_requestor_ip($r);
 
 # info to generate "next" and "previous" buttons and check if message is blocked
-    my ($startblock,$endblock) = &Apache::loncommon::blockcheck(\%setters,'com');
-    my @messages=&sortedmessages(\%blocked,$startblock,$endblock,\$numblocked,$folder,$msgstatus);
+    my ($startblock,$endblock,$triggerblock,$by_ip,$blockdom) =
+        &Apache::loncommon::blockcheck(\%setters,'com',$clientip);
+    my @messages=&sortedmessages(\%blocked,$startblock,$endblock,$by_ip,\$numblocked,$folder,$msgstatus);
     if ( $blocked{$msgid} eq 'ON' ) {
         &printheader($r,'/adm/email',&mt('Display a Message'));
         #$r->print(&mt('You attempted to display a message that is currently blocked because you are enrolled in one or more courses for which there is an ongoing online exam.'));
-        my($blocked, $blocktext) = &Apache::loncommon::blocking_status("com");
+        my($blocked, $blocktext) = &Apache::loncommon::blocking_status("com",$clientip);
         $r->print("<br />".$blocktext);
         return;
     }
@@ -2472,12 +2504,16 @@ sub displaymessage {
                               $showsymb,$env{'user.domain'},$env{'user.name'});
                 if ($symb) {
                     if ($encrypturl =~ /^yes$/i && !$env{'request.role.adv'}) {
-                        $showsymb = &Apache::lonenc::check_encrypt($symb);
+                        unless ($showsymb =~ m{^/enc/}) {
+                            $showsymb = &Apache::lonenc::encrypted($showsymb);
+                        }
                     }
                     $symblink = '?symb='.$showsymb;
                 }
                 if ($encrypturl =~ /^yes$/i && !$env{'request.role.adv'}) {
-                    $showurl = $baseurl;
+                    unless ($showurl =~ m{^/enc/}) {
+                        $showurl = &Apache::lonenc::encrypted($showurl);
+                    }
                 }
                 $r->print(&Apache::lonhtmlcommon::row_title(&mt('Refers to'))
                          .'<a href="'.$showurl.$symblink.'">'.$restitle.'</a>'
@@ -2671,12 +2707,20 @@ sub displayresource {
      && (&Apache::lonnet::allowed('vgr',$content{'courseid'}))) {
         my $symb;
         if (defined($content{'symb'})) {
-            $symb = $content{'symb'};
-        } else { 
-	    $symb=&Apache::lonnet::symbread($content{'baseurl'});
+            $symb = &Apache::lonenc::check_decrypt($content{'symb'});
+        } elsif (defined($content{'baseurl'})) {
+            $symb =
+                &Apache::lonnet::symbread(&Apache::lonenc::check_decrypt($content{'baseurl'}));
         }
 # Could not get a symb, give up
 	unless ($symb) { return $content{'citation'}; }
+        if ($symb =~ /ext\.tool$/) {
+            return '<h2>'.&mt('Current transactions for student (if applicable)').'</h2>'.
+            &Apache::loncommon::get_previous_attempt($symb,
+                                                     $content{'sendername'},
+                                                     $content{'senderdomain'},
+                                                     $content{'courseid'});
+        }
 # Have a symb, can render
 	return '<h2>'.&mt('Current attempts of student (if applicable)').'</h2>'.
 	    &Apache::loncommon::get_previous_attempt($symb,
@@ -2782,8 +2826,15 @@ sub sendoffmail {
         $cnum = $env{'course.'.$env{'request.course.id'}.'.num'};
         $cdom = $env{'course.'.$env{'request.course.id'}.'.domain'};
     }
-    if ($env{'form.send'}) {
-        if (!$env{'form.multiforward'}) { 
+    my $clientip = &Apache::lonnet::get_requestor_ip($r);
+    my %setters;
+    my ($startblock,$endblock,$triggerblock,$by_ip,$blockdom) =
+        &Apache::loncommon::blockcheck(\%setters,'com',$clientip);
+    if ($by_ip) {
+        &printheader($r,'','Sending messages blocked from your location.');
+        return 'blocked';
+    } elsif ($env{'form.send'}) {
+        if (!$env{'form.multiforward'}) {
             if ($group eq '') {
 	        &printheader($r,'','Messages being sent.');
             } else {
@@ -2813,6 +2864,8 @@ sub sendoffmail {
 
 	my $mode = $env{'form.sendmode'};
 	my (%toaddr,$tos,$cc,$bcc,$broadcast);
+        my (%willtrust,%trustchecked,%disallowed);
+        my $serverdefdom = &Apache::lonnet::default_login_domain();
 
 	if ($mode eq 'group') {
             if (defined($env{'form.courserecips'})) {
@@ -2822,9 +2875,17 @@ sub sendoffmail {
                 foreach my $dest (@to) {
                     my ($user,$domain) = split(/:/, $dest);
                     if (($user ne '') && ($domain ne '')) {
-                        my $rec = $user.":".$domain;
-                        $toaddr{$rec} = '';
-                        $broadcast->{$rec} = '';
+                        unless ($trustchecked{$domain}) {
+                            $willtrust{$domain} = &Apache::lonnet::will_trust('msg',$serverdefdom,$domain);
+                            $trustchecked{$domain} = 1;
+                        }
+                        if ($willtrust{$domain}) {
+                            my $rec = $user.":".$domain;
+                            $toaddr{$rec} = '';
+                            $broadcast->{$rec} = '';
+                        } else {
+                            $disallowed{'to'}{$user.":".$domain} = 1; 
+                        }
                     }
                 }
             }
@@ -2835,22 +2896,47 @@ sub sendoffmail {
 		if ($txt) {
                     $rec =~ s/^\s+//;
                     $rec =~ s/\s+$//;
-		    $toaddr{$rec}.=$txt."\n";
-                    $broadcast->{$rec} = '';
+                    my ($recuname,$recudom) = split(/:/,$rec);
+                    unless ($trustchecked{$recudom}) {
+                        $willtrust{$recudom} = &Apache::lonnet::will_trust('msg',$serverdefdom,$recudom);
+                        $trustchecked{$recudom} = 1;
+                    }
+                    if ($willtrust{$recudom}) {
+		        $toaddr{$rec}.=$txt."\n";
+                        $broadcast->{$rec} = '';
+                    } else {
+                        $disallowed{'to'}{$rec} = 1;
+                    }
 		}
 	    }
 	} else {
 	    if (($env{'form.recuname'} ne '') && ($env{'form.recdomain'} ne '')) {
-		$toaddr{$env{'form.recuname'}.':'.$env{'form.recdomain'}}='';
-                $tos->{$env{'form.recuname'}.':'.$env{'form.recdomain'}}='';
+                unless ($trustchecked{$env{'form.recdomain'}}) {
+                    $willtrust{$env{'form.recdomain'}} = &Apache::lonnet::will_trust('msg',$serverdefdom,$env{'form.recdomain'});
+                    $trustchecked{$env{'form.recdomain'}} = 1;
+                }
+                if ($willtrust{$env{'form.recdomain'}}) {
+		    $toaddr{$env{'form.recuname'}.':'.$env{'form.recdomain'}}='';
+                    $tos->{$env{'form.recuname'}.':'.$env{'form.recdomain'}}='';
+                } else {
+                    $disallowed{'to'}{$env{'form.recuname'}.':'.$env{'form.recdomain'}}; 
+                }
 	    }
 	}
         if ($env{'form.additionalrec_to'}) {
             foreach my $rec (split(/\s*,\s*/,$env{'form.additionalrec_to'})) {
                 my ($auname,$audom)=split(/:/,$rec);
                 if (($auname ne "") && ($audom ne "")) {
-                    $toaddr{$auname.':'.$audom}='';
-                    $tos->{$auname.':'.$audom}='';
+                    unless ($trustchecked{$audom}) {
+                        $willtrust{$audom} = &Apache::lonnet::will_trust('msg',$serverdefdom,$audom);
+                        $trustchecked{$audom} = 1;
+                    }
+                    if ($willtrust{$audom}) {
+                        $toaddr{$auname.':'.$audom}='';
+                        $tos->{$auname.':'.$audom}='';
+                    } else {
+                        $disallowed{'to'}{$auname.':'.$audom};
+                    }
                 }
             }
         }
@@ -2860,8 +2946,16 @@ sub sendoffmail {
             foreach my $rec (@toreplies) {
                 my ($auname,$audom)=split(/:/,$rec);
                 if (($auname ne "") && ($audom ne "")) {
-                    $toaddr{$auname.':'.$audom}='';
-                    $tos->{$auname.':'.$audom}='';
+                    unless ($trustchecked{$audom}) {
+                        $willtrust{$audom} = &Apache::lonnet::will_trust('msg',$serverdefdom,$audom);
+                        $trustchecked{$audom} = 1;
+                    }
+                    if ($willtrust{$audom}) {
+                        $toaddr{$auname.':'.$audom}='';
+                        $tos->{$auname.':'.$audom}='';
+                    } else {
+                        $disallowed{'to'}{$auname.':'.$audom};
+                    } 
                 }
             }
         }
@@ -2869,9 +2963,17 @@ sub sendoffmail {
 	    foreach my $rec (split(/\s*,\s*/,$env{'form.additionalrec_cc'})) {
 		my ($auname,$audom)=split(/:/,$rec);
 		if (($auname ne "") && ($audom ne "")) {
-                    $toaddr{$auname.':'.$audom}='';
                     if (!defined($tos->{$auname.':'.$audom})) {
-		        $cc->{$auname.':'.$audom}='';
+                        unless ($trustchecked{$audom}) {
+                            $willtrust{$audom} = &Apache::lonnet::will_trust('msg',$serverdefdom,$audom);
+                            $trustchecked{$audom} = 1;
+                        }
+                        if ($willtrust{$audom}) {
+                            $toaddr{$auname.':'.$audom}='';
+		            $cc->{$auname.':'.$audom}='';
+                        } else {
+                            $disallowed{'cc'}{$auname.':'.$audom};
+                        }
                     }
 		}
 	    }
@@ -2882,9 +2984,17 @@ sub sendoffmail {
             foreach my $rec (@ccreplies) {
                 my ($auname,$audom)=split(/:/,$rec);
                 if (($auname ne "") && ($audom ne "")) {
-                    $toaddr{$auname.':'.$audom}='';
                     if (!defined($tos->{$auname.':'.$audom})) {
-                        $cc->{$auname.':'.$audom}='';
+                        unless ($trustchecked{$audom}) {
+                            $willtrust{$audom} = &Apache::lonnet::will_trust('msg',$serverdefdom,$audom);
+                            $trustchecked{$audom} = 1;
+                        }
+                        if ($willtrust{$audom}) {
+                            $toaddr{$auname.':'.$audom}='';
+                            $cc->{$auname.':'.$audom}='';
+                        } else {
+                            $disallowed{'cc'}{$auname.':'.$audom} = 1;
+                        }
                     }
                 }
             }
@@ -2895,9 +3005,17 @@ sub sendoffmail {
             foreach my $rec (@groupreplies) {
                 my ($auname,$audom)=split(/:/,$rec);
                 if (($auname ne "") && ($audom ne "")) {
-                    $toaddr{$auname.':'.$audom}='';
                     if (!defined($tos->{$auname.':'.$audom})) {
-                        $broadcast->{$auname.':'.$audom}='';
+                        unless ($trustchecked{$audom}) {
+                            $willtrust{$audom} = &Apache::lonnet::will_trust('msg',$serverdefdom,$audom);
+                            $trustchecked{$audom} = 1;
+                        }
+                        if ($willtrust{$audom}) {
+                            $toaddr{$auname.':'.$audom}='';
+                            $broadcast->{$auname.':'.$audom}='';
+                        } else {
+                            $disallowed{'to'}{$auname.':'.$audom} = 1;
+                        }
                     }
                 }
             }
@@ -2906,10 +3024,18 @@ sub sendoffmail {
             foreach my $rec (split(/\s*,\s*/,$env{'form.additionalrec_bcc'})) {
                 my ($auname,$audom)=split(/:/,$rec);
                 if (($auname ne "") && ($audom ne "")) {
-                    $toaddr{$auname.':'.$audom}='';
-                    if ((!defined($tos->{$auname.':'.$audom})) && 
+                    if ((!defined($tos->{$auname.':'.$audom})) &&
                         (!defined($cc->{$auname.':'.$audom}))) {
-                        $bcc->{$auname.':'.$audom}='';
+                        unless ($trustchecked{$audom}) {
+                            $willtrust{$audom} = &Apache::lonnet::will_trust('msg',$serverdefdom,$audom);
+                            $trustchecked{$audom} = 1;
+                        }
+                        if ($willtrust{$audom}) {
+                            $toaddr{$auname.':'.$audom}='';
+                            $bcc->{$auname.':'.$audom}='';
+                        } else {
+                            $disallowed{'bcc'}{$auname.':'.$audom} = 1;
+                        }
                     }
                 }
             }
@@ -2929,42 +3055,42 @@ sub sendoffmail {
         } else {
             $savemsg=&Apache::lonfeedback::clear_out_html($env{'form.message'});
         }
-        my %reciphash = (
-                           to => $tos,
-                           cc => $cc,
-                           bcc => $bcc,
-                        );
-        if ($mode eq 'group') {
-            if ($group eq '') {
-                $reciphash{'course_broadcast'} = $broadcast;
-            } else {
-                if ($env{'form.groupmail'} eq 'cc') {
-                    $reciphash{'group_cc_broadcast'} = $broadcast;
+        my ($recipid, @recusers, @recudoms, %permresults);
+        if (keys(%toaddr) > 0) {
+            my %reciphash = (
+                               to => $tos,
+                               cc => $cc,
+                               bcc => $bcc,
+                            );
+            if ($mode eq 'group') {
+                if ($group eq '') {
+                    $reciphash{'course_broadcast'} = $broadcast;
                 } else {
-                    $reciphash{'group_bcc_broadcast'} = $broadcast;
+                    if ($env{'form.groupmail'} eq 'cc') {
+                        $reciphash{'group_cc_broadcast'} = $broadcast;
+                    } else {
+                        $reciphash{'group_bcc_broadcast'} = $broadcast;
+                    }
                 }
             }
-        }
-        my ($recipid,$recipstatus) = 
-            &Apache::lonmsg::store_recipients($msgsubj,$env{'user.name'},
-                                       $env{'user.domain'},\%reciphash);
-        if ($recipstatus ne 'ok') {
-            &Apache::lonnet::logthis('Failed to store To, Bcc and Cc recipients for '.$env{'user.name'}.':'.$env{'user.domain'});
-        }
-        if ($env{'form.attachment'}) {
-            if (length($env{'form.attachment'}) <= 1048576) {
-                $attachmenturl=&Apache::lonnet::userfileupload('attachment',undef,'feedback/'.$now);
-            } else {
-                $r->print('<p><span class="LC_warning">'.&mt('Attachment not included - exceeded permitted length').'</span><br /></p>');
-            }
-        } elsif ($env{'form.multiforward'}) {
-            if ($env{'form.attachmenturl'} ne '') {
-                $attachmenturl = $env{'form.attachmenturl'};
+            ($recipid,my $recipstatus) = 
+                &Apache::lonmsg::store_recipients($msgsubj,$env{'user.name'},
+                                                  $env{'user.domain'},\%reciphash);
+            if ($recipstatus ne 'ok') {
+                &Apache::lonnet::logthis('Failed to store To, Bcc and Cc recipients for '.$env{'user.name'}.':'.$env{'user.domain'});
+            }
+            if ($env{'form.attachment'}) {
+                if (length($env{'form.attachment'}) <= 1048576) {
+                    $attachmenturl=&Apache::lonnet::userfileupload('attachment',undef,'feedback/'.$now);
+                } else {
+                    $r->print('<p><span class="LC_warning">'.&mt('Attachment not included - exceeded permitted length').'</span><br /></p>');
+                }
+            } elsif ($env{'form.multiforward'}) {
+                if ($env{'form.attachmenturl'} ne '') {
+                    $attachmenturl = $env{'form.attachmenturl'};
+                }
             }
         }
-        my @recusers;
-        my @recudoms;
-        my %permresults;
 	foreach my $address (sort(keys(%toaddr))) {
 	    my ($recuname,$recdomain)=split(/\:/,$address);
             my $msgtxt = $savemsg;
@@ -3102,6 +3228,23 @@ sub sendoffmail {
                 $r->print($message);
             }
         }
+        if (keys(%disallowed)) {
+            if ((ref($disallowed{'to'}) eq 'HASH') && (keys(%{$disallowed{'to'}}) > 0)) {
+                $r->print(&mt("The following recipients were excluded because the user's domain does not accept messages from server's domain:").'<ul><li>'.
+                          join("</li><li>\n",sort(keys(%{$disallowed{'to'}}))).
+                          '</li><ul><br />');
+            }
+            if (ref($disallowed{'cc'}) eq 'HASH') {
+                $r->print(&mt("The following CCs were excluded because the user's domain does not accept messages from server's domain:").'<ul><li>'.
+                          join("</li><li>\n",sort(keys(%{$disallowed{'cc'}}))).
+                          '</li><ul><br />');
+            }
+            if (ref($disallowed{'bcc'}) eq 'HASH') {
+                $r->print(&mt("The following BCCs were excluded because the user's domain does not accept messages from server's domain:").'<ul><li>'.
+                          join("</li><li>\n",sort(keys(%{$disallowed{'bcc'}}))).
+                          '</li><ul><br />');
+            }
+        }
     } else {
         &printheader($r,'','Messages cancelled.');
         return 'cancelled';
@@ -3127,9 +3270,24 @@ sub handler {
          'sendreply','compose','sendmail','critical','recname','recdom',
          'recordftf','sortedby','folder','startdis','interdis',
 	 'showcommentbaseurl','dismode','group','subject','text','ref',
-         'msgstatus']);
+         'msgstatus','btoken']);
     $sqs='&amp;sortedby='.$env{'form.sortedby'};
 
+# ----------- Check if access was from balancer to server with existing session
+
+    if ($env{'form.btoken'}) {
+        my %info = &Apache::lonnet::tmpget($env{'form.btoken'});
+        &Apache::lonnet::tmpdel($env{'form.btoken'});
+        delete($env{'form.btoken'});
+        unless ($env{'form.display'}) {
+            if (($info{'display'}) && ($info{'mailrecip'})) {
+                if (&unescape($info{'mailrecip'}) eq $env{'user.name'}.':'.$env{'user.domain'}) {
+                    $env{'form.display'} = &unescape($info{'display'});
+                }
+            }
+        }
+    }
+
 # ------------------------------------------------------ They checked for email
     &Apache::lonnet::put('email_status',{'recnewemail'=>0});
 
@@ -3384,8 +3542,12 @@ sub handler {
                 my $count = keys(%forwardfail);
                 my $message = &Apache::lonhtmlcommon::confirm_success(&mt('Could not forward [quant,_1,message].',$count),1);
                 foreach my $key (keys(%forwardfail)) {
-                    $message .= '<br />'.&mt('Could not deliver forwarded message.').'</span> '.
-                                &mt('The recipient addresses may need to be corrected').' ('.$forwardfail{$key}.')';
+                    $message .= '<br />'.&mt('Could not deliver forwarded message.').' ';
+                    if ($forwardfail{$key} eq 'blocked') {
+                        $message .= &mt('Sending messages is blocked from your IP address');
+                    } else {
+                        $message .= &mt('The recipient addresses may need to be corrected').' ('.$forwardfail{$key}.')';
+                    }
                 }
                 $message = &Apache::loncommon::confirmwrapper($message);
                 $r->print($message);