--- loncom/auth/switchserver.pm	2018/07/04 16:58:19	1.41
+++ loncom/auth/switchserver.pm	2019/01/27 16:02:43	1.48
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # Switch Servers Handler
 #
-# $Id: switchserver.pm,v 1.41 2018/07/04 16:58:19 raeburn Exp $
+# $Id: switchserver.pm,v 1.48 2019/01/27 16:02:43 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -31,7 +31,7 @@ package Apache::switchserver;
 use strict;
 use Apache::Constants qw(:common);
 use Apache::lonnet;
-use Apache::lonmenu;
+use Digest::MD5 qw(md5_hex);
 use CGI::Cookie();
 use Apache::lonlocal;
 use LONCAPA qw(:DEFAULT :match);
@@ -49,7 +49,7 @@ sub init_env {
     }
     my $lonidsdir=$r->dir_config('lonIDsDir');
     &Apache::lonnet::transfer_profile_to_env($lonidsdir,$handle);
-    
+
     return $r->dir_config('lonIDsDir')."/$handle.id";
 }
 
@@ -68,6 +68,24 @@ sub do_redirect {
     return OK;
 }
 
+sub balancer_cookieid {
+    my ($r,$desthost,$uname,$udom) = @_;
+    my @hosts = &Apache::lonnet::current_machine_ids();
+    my $newcookieid;
+    unless (grep(/^\Q$desthost\E$/,@hosts)) {
+        my $balancedir=$r->dir_config('lonBalanceDir');
+        $newcookieid = &md5_hex(&md5_hex(time.{}.rand().$$));
+        my $cookie = $udom.'_'.$uname.'_'.$newcookieid;
+        my $balcookie = "balanceID=$cookie; path=/; HttpOnly;";
+        if (open(my $fh,'>',"$balancedir/$cookie.id")) {
+            print $fh $desthost;
+            close($fh);
+            $r->headers_out->add('Set-cookie' => $balcookie);
+        }
+    }
+    return $newcookieid;
+}
+
 sub flush_course_logs {
     &Apache::lonnet::flushcourselogs();
     return OK;
@@ -101,7 +119,7 @@ sub handler {
         if ($Apache::lonnet::protocol{$env{'form.otherserver'}} eq 'https') {
             $protocol = $Apache::lonnet::protocol{$env{'form.otherserver'}};
         }
-    } 
+    }
 
     if ($env{'user.name'} eq 'public'
 	&& $env{'user.domain'} eq 'public') {
@@ -116,11 +134,11 @@ sub handler {
     }
 
     my $skip_canhost_check = '';
+    my $now = time;
     if ($env{'form.role'}) {
         if (!exists($env{'user.role.'.$env{'form.role'}})) {
             delete($env{'form.role'});
         } else {
-            my $now = time;
             my ($start,$end) = split(/\./,$env{'user.role.'.$env{'form.role'}});
             if (($start && $start > $now) || ($end && $end < $now)) {
                 delete($env{'form.role'});
@@ -131,8 +149,8 @@ sub handler {
             } elsif ($env{'form.role'} =~ m{^[ac]a\./($match_domain)/($match_username)$}) {
                 my ($audom,$auname) = ($1,$2);
                 if (&Apache::lonnet::homeserver($auname,$audom) eq $env{'form.otherserver'}) {
-                    if ((&Apache::lonnet::will_trust('othcoau',$audom,$env{'user.domain'})) &&
-                        (&Apache::lonnet::will_trust('coremau',$env{'user.domain'},$audom))) {                             
+                    if ((&Apache::lonnet::will_trust('othcoau',$env{'user.domain'},$audom)) &&
+                        (&Apache::lonnet::will_trust('coaurem',$audom,$env{'user.domain'}))) {                             
                         $skip_canhost_check = 1;
                     }
                 }
@@ -176,7 +194,7 @@ sub handler {
             }
         }
     }
-    my %temp=('switchserver' => time.':'.$env{'form.otherserver'},
+    my %temp=('switchserver' => $now.':'.$env{'form.otherserver'},
 	      $env{'form.role'});
     &Apache::lonnet::put('email_status',\%temp);
     my $logmsg = "Switch Server to $env{'form.otherserver'}";
@@ -212,13 +230,44 @@ sub handler {
 	   
 # ---------------------------------------------------------------- Get handover
 
-    my ($is_balancer) = &Apache::lonnet::check_loadbalancing($env{'user.name'},$env{'user.domain'});
-    my %info=('ip'       => $ENV{'REMOTE_ADDR'},
-	      'domain'   => $env{'user.domain'},
-	      'username' => $env{'user.name'},
-	      'role'     => $env{'form.role'},
-	      'server'   => $r->dir_config('lonHostID'),
-	      'balancer' => $is_balancer);
+    my $newcookieid;
+    my ($is_balancer,$posshost,$setcookie,$offloadto,$dom_balancers) =
+        &Apache::lonnet::check_loadbalancing($env{'user.name'},$env{'user.domain'});
+    if ($is_balancer && $setcookie && $env{'form.otherserver'}) {
+
+        # Set a balancer cookie unless browser already sent LON-CAPA load balancer
+        # cookie which points at the target server
+        my ($found_server,$balancer_cookie) = &Apache::lonnet::check_for_balancer_cookie($r,1);
+
+        unless (($found_server eq $env{'form.otherserver'}) &&
+                ($balancer_cookie =~ /^\Q$env{'user.domain'}\E_\Q$env{'user.name'}\E_/)) {
+            $newcookieid = &balancer_cookieid($r,$env{'form.otherserver'},
+                                              $env{'user.name'},$env{'user.domain'});
+        }
+    }
+
+    my %info=('ip'            => $ENV{'REMOTE_ADDR'},
+              'domain'        => $env{'user.domain'},
+              'username'      => $env{'user.name'},
+              'home'          => $env{'user.home'},
+              'role'          => $env{'form.role'},
+              'server'        => $r->dir_config('lonHostID'),
+              'balancer'      => $is_balancer,
+              'dom_balancers' => $dom_balancers,
+              'offloadto'     => '');
+    if (ref($offloadto) eq 'HASH') {
+        foreach my $key (keys(%{$offloadto})) {
+            if (ref($offloadto->{$key}) eq 'ARRAY') {
+                $info{'offloadto'} .= $key.'='.join(',',@{$offloadto->{$key}}).'&';
+            }
+        }
+        $info{'offloadto'} =~ s/\&$//;
+    } elsif (ref($offloadto) eq 'ARRAY') {
+        $info{'offloadto'} = join(',',@{$offloadto});
+    }
+    if ($newcookieid) {
+        $info{'balcookie'} = $newcookieid;
+    }
     if ($env{'form.origurl'}) {
         $info{'origurl'} = $env{'form.origurl'};
     }
@@ -231,6 +280,15 @@ sub handler {
     if ($env{'request.sso.reloginserver'}) {
         $info{'sso.reloginserver'} = $env{'request.sso.reloginserver'};
     }
+    if ($env{'request.linkprot'}) {
+        $info{'linkprot'} = $env{'request.linkprot'};
+    }
+    if ($env{'request.deeplink.login'}) {
+        $info{'deeplink.login'} = $env{'request.deeplink.login'};
+        if ($env{'request.linkkey'}) {
+            $info{'linkkey'} = $env{'request.linkkey'};
+        }
+    }
     if ($env{'request.lti.login'}) {
         $info{'lti.login'} = $env{'request.lti.login'};
     }