--- loncom/auth/migrateuser.pm	2018/11/28 05:05:30	1.36
+++ loncom/auth/migrateuser.pm	2019/06/15 02:50:04	1.44
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # Starts a user off based of an existing token.
 #
-# $Id: migrateuser.pm,v 1.36 2018/11/28 05:05:30 raeburn Exp $
+# $Id: migrateuser.pm,v 1.44 2019/06/15 02:50:04 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -33,9 +33,11 @@ use LONCAPA qw(:DEFAULT :match);
 use Apache::Constants qw(:common :http :methods);
 use Apache::lonauth;
 use Apache::lonnet;
+use Apache::loncommon;
 use Apache::lonlocal;
 use Apache::lonlogin();
 use Apache::ltiauth;
+use Apache::switchserver;
 use CGI::Cookie;
 
 sub goto_login {
@@ -113,12 +115,57 @@ sub lti_check {
         if ($data->{'lti.rosterurl'}) {
             $lti_env{'request.lti.rosterurl'} = $data->{'lti.rosterurl'};
         }
+        if (($data->{'balancer'}) && ($data->{'server'}) && ($data->{'balcookie'})) {
+            $lti_env{'request.balancercookie'} = $data->{'server'}.':'.$data->{'balcookie'};
+        }
     }
     return \%lti_env;
 }
 
+sub canhost {
+    my ($uname,$udom,$lonhost,$loncaparev) = @_;
+    my $canhost;
+    if (&Apache::lonnet::is_library($lonhost)) {
+        my @possdoms = &Apache::lonnet::current_machine_domains();
+        my %roleshash = &Apache::lonnet::get_my_roles($uname,$udom,'userroles','',['ca','aa'],\@possdoms);
+        if (keys(%roleshash)) {
+            foreach my $key (keys(%roleshash)) {
+                my $audom = (split(/:/,$key))[1];
+                if ((&Apache::lonnet::will_trust('othcoau',$udom,$audom)) &&
+                    (&Apache::lonnet::will_trust('coaurem',$audom,$udom))) {
+                    $canhost = 1;
+                    last;
+                }
+            }
+        }
+    }
+    unless ($canhost) {
+        my $uprimary_id = &Apache::lonnet::domain($udom,'primary');
+        my $uint_dom = &Apache::lonnet::internet_dom($uprimary_id);
+        my @intdoms;
+        my $internet_names = &Apache::lonnet::get_internet_names($lonhost);
+        if (ref($internet_names) eq 'ARRAY') {
+            @intdoms = @{$internet_names};
+        }
+        if ($uint_dom ne '' && grep(/^\Q$uint_dom\E$/,@intdoms)) {
+            $canhost = 1;
+        } else {
+            my $hostname = &Apache::lonnet::hostname($lonhost);
+            my $serverhomeID = &Apache::lonnet::get_server_homeID($hostname);
+            my $serverhomedom = &Apache::lonnet::host_domain($serverhomeID);
+            my %defdomdefaults = &Apache::lonnet::get_domain_defaults($serverhomedom);
+            my %udomdefaults = &Apache::lonnet::get_domain_defaults($udom);
+            $canhost =
+                &Apache::lonnet::can_host_session($udom,$lonhost,$loncaparev,
+                                                  $udomdefaults{'remotesessions'},
+                                                  $defdomdefaults{'hostedsessions'});
+        }
+    }
+    return $canhost;
+}
+
 sub ip_changed {
-    my ($r,$udom,$camefrom,$dataref) = @_;
+    my ($r,$udom,$camefrom,$idsref,$dataref) = @_;
     &Apache::loncommon::content_type($r,'text/html');
     $r->send_http_header;
     if (ref($dataref) eq 'HASH') {
@@ -167,8 +214,10 @@ sub ip_changed {
         my $lonhost= $r->dir_config('lonHostID');
         my $switchto = $lonhost;
         if ($rule_in_effect ne 'offloadedto') {
-            my $hosthere;
-            my @ids=&Apache::lonnet::current_machine_ids();
+            my ($hosthere,@ids);
+            if (ref($idsref) eq 'ARRAY') {
+                @ids=@{$idsref};
+            }
             unless ($rule_in_effect eq 'balancer') {
                 if (grep(/^\Q$rule_in_effect\E$/,@ids)) {
                     $hosthere = 1;
@@ -294,7 +343,11 @@ sub logout {
     }
     my (%info,%user_info,%lti_info);
     if (ref($lti_env) eq 'HASH') {
-        %lti_info = %{$lti_env};
+        foreach my $key (sort(keys(%{$lti_env}))) {
+            if ($key =~ /^request\.(.+)$/) {
+                $lti_info{$1} = $lti_env->{$key};
+            }
+        }
     }
     my $lonhost = $r->dir_config('lonHostID');
     if (ref($data) eq 'HASH') {
@@ -316,6 +369,13 @@ sub logout {
                                        {'redirect'       => [0.1,$url],
                                         'only_body'      => 1,}).
         &Apache::loncommon::end_page());
+    if ($env{'request.balancercookie'}) {
+        my ($balancer,$cookie) = split(/:/,$env{'request.balancercookie'});
+        if ((&Apache::lonnet::hostname($balancer)) && ($cookie =~ /^[a-f0-9]{32}$/)) {
+            $cookie = $env{'user.domain'}.'_'.$env{'user.name'}.'_'.$cookie;
+            &Apache::lonnet::delbalcookie($cookie,$balancer);
+        }
+    }
     $r->register_cleanup(\&flush_course_logs);
     return;
 }
@@ -325,17 +385,39 @@ sub conlost_userhome {
     return unless ((ref($idsref) eq 'ARRAY') && (ref($dataref) eq 'HASH'));
     my @ids = @{$idsref};
     my %data = %{$dataref};
-    my (%conlost,%posstargets);
-    my $lonhost = $r->dir_config('lonHostID');
-    $conlost{$lonhost} = 1;
+    my ($lonhost,$lowest_load,$otherserver,$is_balancer,%conlost,%posstargets);
+    $lonhost = $r->dir_config('lonHostID');
+    if (grep(/^\Q$lonhost\E$/,split(/,/,$data{'dom_balancers'}))) {
+        $is_balancer = 1;
+    }
+    $lowest_load = 30000;
     if ($data{'conlost'} ne '') {
         map { $conlost{$_} = 1; } split(/,/,$data{'conlost'});
     }
-    my ($lowest_load,$otherserver);
-    $lowest_load = 30000;
+    if ($data{'loncfail'}) {
+        if ($lonhost ne $data{'from_balancer'}) {
+            my ($is_balancer,$posshost,$setcookie,$offloadto,$dom_balancers) =
+                &Apache::lonnet::check_loadbalancing($data{'username'},$data{'domain'});
+            if ($is_balancer) {
+                if (ref($offloadto) eq 'HASH') {
+                    $data{'offloadto'} = '';
+                    foreach my $key (keys(%{$offloadto})) {
+                        if (ref($offloadto->{$key}) eq 'ARRAY') {
+                            $data{'offloadto'} .= $key.'='.join(',',@{$offloadto->{$key}}).'&';
+                        }
+                    }
+                    $data{'offloadto'} =~ s/\&$//;
+                } elsif (ref($offloadto) eq 'ARRAY') {
+                    $data{'offloadto'} = join(',',@{$offloadto});
+                }
+            }
+        }
+    } else {
+        $conlost{$lonhost} = 1;
+        $data{'conlost'} = join(',',sort(keys(%conlost)));
+    }
     if ($data{'offloadto'} =~ /\&/) {
-        my @items = split(/\&/,$data{'offloadto'});
-        foreach my $item (@items) {
+        foreach my $item (split(/\&/,$data{'offloadto'})) {
             my ($type,$targets) = split(/\=/,$item);
             @{$posstargets{$type}} = split(/,/,$targets);
         }
@@ -347,8 +429,8 @@ sub conlost_userhome {
     }
     if (ref($posstargets{'primary'}) eq 'ARRAY') {
         foreach my $try_server (@{$posstargets{'primary'}}) {
-            next if (grep(/^\Q$try_server\E$/,@ids));
             next if ($conlost{$try_server});
+            next if ((grep(/^\Q$try_server\E$/,@ids)) && !$data{'loncfail'});
             ($otherserver,$lowest_load) =
                 &Apache::lonnet::compare_server_load($try_server,
                                                      $otherserver,
@@ -359,36 +441,109 @@ sub conlost_userhome {
     if (!$found_server) {
         if (ref($posstargets{'default'}) eq 'ARRAY') {
             foreach my $try_server (@{$posstargets{'default'}}) {
+                next if ($conlost{$try_server});
+                next if ((grep(/^\Q$try_server\E$/,@ids)) && !$data{'loncfail'});
                 ($otherserver,$lowest_load) =
-                &Apache::lonnet::compare_server_load($try_server,
-                                                     $otherserver,
-                                                     $lowest_load);
+                    &Apache::lonnet::compare_server_load($try_server,
+                                                         $otherserver,
+                                                         $lowest_load);
             }
         }
     }
     if ($otherserver ne '') {
         my $switchto = &Apache::lonnet::hostname($otherserver);
         if ($switchto ne '') {
-            my $protocol = $Apache::lonnet::protocol{$switchto};
-            $protocol = 'http' if ($protocol ne 'https');
-            my $url = $protocol.'://'.$switchto.'/adm/login?'.
-                                    'domain='.$env{'user.domain'}.
-                                    '&username='.$env{'user.name'};
-            $data{'conlost'} = join(',',sort(keys(%conlost)));
             $data{'server'} = $lonhost;
+            if ($data{'loncfail'}) {
+                delete($data{'loncfail'});
+            }
             if (grep(/^\Q$otherserver\E$/,split(/,/,$data{'dom_balancers'}))) {
-                $data{'noloadbalance'} = $otherserver; 
+                $data{'noloadbalance'} = $otherserver;
             }
-            my $token = &Apache::lonnet::tmpput(\%data,$otherserver);
-            $url .= '&token='.$token;
-            $r->send_http_header;
-            $r->print(
-                &Apache::loncommon::start_page('Switching Server ...',undef,
-                                               {'redirect'       => [0.1,$url]}).
-                                                &Apache::loncommon::end_page());
+            &do_server_switch($r,$otherserver,$switchto,$is_balancer,\%data);
             return $otherserver;
+        } else {
+            #FIXME Contents of $data{offloadto} contains invalid hostID.
+        }
+    } else {
+        my (%poss_balancers,%tried_balancers);
+        map { $poss_balancers{$_} = 1; } split(/,/,$data{'dom_balancers'});
+        map { $tried_balancers{$_} = 1; } split(/,/,$data{'tried_balancers'});
+        if (keys(%poss_balancers)) {
+            foreach my $try_server (sort(keys(%poss_balancers))) {
+                next if (grep(/^\Q$try_server\E$/,@ids));
+                next if (($data{'loncfail'}) && ($tried_balancers{$try_server}));
+                my $alreadytried;
+                foreach my $key (keys(%posstargets)) {
+                    if ((ref($posstargets{$key}) eq 'ARRAY') &&
+                        (grep(/^\Q$try_server\E$/,@{$posstargets{$key}}))) {
+                        $alreadytried = 1;
+                        last;
+                    }
+                }
+                unless ($alreadytried) {
+                    if (&Apache::lonnet::reply('ping',$try_server) eq $try_server) {
+                        $otherserver = $try_server;
+                        last;
+                    }
+                }
+            }
+        }
+        if ($otherserver ne '') {
+            my $switchto = &Apache::lonnet::hostname($otherserver);
+            if ($switchto ne '') {
+                $data{'server'} = $lonhost;
+                $data{'loncfail'} = $lonhost;
+                $tried_balancers{$otherserver} = 1;
+                $data{'tried_balancers'} = join(',',sort(keys(%tried_balancers)));
+                &do_server_switch($r,$otherserver,$switchto,$is_balancer,\%data);
+                return $otherserver;
+            } else {
+                #FIXME Contents of $data{'dom_balancers'} contains invalid hostID.
+            }
+        } else {
+            if ($data{'loncfail'}) {
+                #FIXME Nowhere to go. 
+            } else {
+                # FIXME Send back to a balancer (no token); different balancer if this is a balancer.
+                # Send command to balancer to exclude this host using http instead on lonc/lond
+            }
+        }
+    }
+    return;
+}
+
+sub do_server_switch {
+    my ($r,$otherserver,$switchto,$is_balancer,$dataref) = @_;
+    if (ref($dataref) eq 'HASH') {
+        my $domain = $dataref->{'domain'};
+        my $username = $dataref->{'username'};
+        # If this is a balancer set a balancer cookie unless browser already sent
+        # LON-CAPA load balancer cookie which points at the target server.
+        if ($is_balancer) {
+            my $newcookieid;
+            my ($found_server,$balancer_cookie) = &Apache::lonnet::check_for_balancer_cookie($r,1);
+            unless (($found_server eq $otherserver) &&
+                    ($balancer_cookie =~ /^\Q$domain\E_\Q$username\E_/)) {
+                $newcookieid =
+                    &Apache::switchserver::balancer_cookieid($r,$otherserver,$username,$domain);
+                if ($newcookieid) {
+                    $dataref->{'balcookie'} = $newcookieid;
+                }
+            }
         }
+        my $token = &Apache::lonnet::tmpput($dataref,$otherserver);
+        my $protocol = $Apache::lonnet::protocol{$otherserver};
+        $protocol = 'http' if ($protocol ne 'https');
+        my $url = $protocol.'://'.$switchto.'/adm/login?domain='.$domain.
+                                 '&username='.$username.'&token='.$token;
+        $r->send_http_header;
+        $r->print(
+        &Apache::loncommon::start_page('Switching Server ...',undef,
+                                       {'redirect'       => [0.1,$url]}).
+        &Apache::loncommon::end_page());
     }
+    return;
 }
 
 sub log_switch {
@@ -436,24 +591,33 @@ sub handler {
     if (!defined($data{'username'}) || !defined($data{'domain'})) {
         return &goto_login($r,undef,\%data);
     }
+    my ($home,@ids);
+    @ids=&Apache::lonnet::current_machine_ids();
     if ($data{'ip'} ne $ENV{'REMOTE_ADDR'}) {
         &Apache::lonnet::logthis('IP change when session migration requested -- was: '.
                  $data{'ip'}.'; now: '.$ENV{'REMOTE_ADDR'}.' for '.$data{'username'}.':'.$data{'domain'});
-	return &ip_changed($r,$data{'domain'},$data{'server'},\%data);
+	return &ip_changed($r,$data{'domain'},$data{'server'},\@ids,\%data);
     }
-
-    my $home=&Apache::lonnet::homeserver($data{'username'},$data{'domain'});
-    if ($home eq 'no_host') {
-        if (($data{'home'} ne '') && (&Apache::lonnet::hostname($data{'home'}))) {
-            &Apache::lonnet::reconlonc($data{'home'});
-            $home=&Apache::lonnet::homeserver($data{'username'},$data{'domain'});
-            if ($home eq 'no_host') {
-                my @ids=&Apache::lonnet::current_machine_ids();
-                unless (grep(/^\Q$data{'home'}\E$/,@ids)) {
-                    if (&Apache::lonnet::reply('ping',$data{'home'}) eq 'con_lost') {
-                        my $otherserver = &conlost_userhome($r,\@ids,\%data);
-                        if ($otherserver ne '') {
-                            &Apache::lonnet::logthis("No connection to home server ($data{'home'}) for $data{'username'}:$data{'domain'}. Switching to $otherserver");
+    if ($data{'loncfail'}) {
+        &Apache::lonnet::logthis('Returned from '.$data{'server'}.' -- no connection to library node or other access node(s)');
+        my $otherserver = &conlost_userhome($r,\@ids,\%data);
+        if ($otherserver ne '') {
+            &Apache::lonnet::logthis("Switching to $otherserver");
+        }
+        return OK;
+    } else {
+        $home=&Apache::lonnet::homeserver($data{'username'},$data{'domain'});
+        if ($home eq 'no_host') {
+            if (($data{'home'} ne '') && (&Apache::lonnet::hostname($data{'home'}))) {
+                &Apache::lonnet::reconlonc($data{'home'});
+                $home=&Apache::lonnet::homeserver($data{'username'},$data{'domain'});
+                if ($home eq 'no_host') {
+                    unless (grep(/^\Q$data{'home'}\E$/,@ids)) {
+                        if (&Apache::lonnet::reply('ping',$data{'home'}) eq 'con_lost') {
+                            my $otherserver = &conlost_userhome($r,\@ids,\%data);
+                            if ($otherserver ne '') {
+                                &Apache::lonnet::logthis("No connection to home server ($data{'home'}) for $data{'username'}:$data{'domain'}. Switching to $otherserver");
+                            }
                             return OK;
                         }
                     }
@@ -467,11 +631,19 @@ sub handler {
         $udom=$data{'domain'};
     }
     if ($home eq 'no_host') { return &goto_login($r,$udom,\%data); }
-    if (&Apache::lonnet::hostname($home) eq '') { return &goto_login($r,$udom,\%data); } 
+    if (&Apache::lonnet::hostname($home) eq '') { return &goto_login($r,$udom,\%data); }
+
+    unless (grep(/^\Q$home\E$/,@ids)) {
+        my $lonhost = $r->dir_config('lonHostID');
+        my $loncaparev = $r->dir_config('lonVersion');
+        unless (&canhost($data{'username'},$data{'domain'},$lonhost,$loncaparev)) {
+            return &goto_login($r,$udom,\%data);
+        }
+    }
 
     my $rolemsg;
     if ($data{'role'}) {
-        $rolemsg = "role: $data{'role'}"; 
+        $rolemsg = "role: $data{'role'}";
     } else {
         $rolemsg = '(no role)';
     }
@@ -488,6 +660,16 @@ sub handler {
         $extra_env = $lti_env;
     }
 
+    if (($data{'conlost'}) && ($data{'server'})) {
+        my @conlosts = split(/,/,$data{'conlost'});
+        my $switchfrom = $data{'server'};
+        if (@conlosts) {
+            if (grep(/^\Q$switchfrom\E$/,@conlosts)) {
+                &log_switch($r,\%data,$extra_env);
+            }
+        }
+    }
+
     my %form;
     if ($data{'symb'} ne '') {
         $form{'symb'} = $data{'symb'};
@@ -499,21 +681,61 @@ sub handler {
         $form{'noloadbalance'} = $data{'noloadbalance'};
     }
 
-    if (($data{'conlost'}) && ($data{'server'})) {
-        my @conlosts = split(/,/,$data{'conlost'});
-        my $switchfrom = $data{'server'};
-        if (@conlosts) {
-            if (grep(/^\Q$switchfrom\E$/,@conlosts)) {
-                &log_switch($r,\%data,$extra_env);
-            }
-        }
-    }
-
     if (!$data{'role'}) {
 	my $handle = &Apache::lonnet::check_for_valid_session($r);
 	if ($handle) {
 	    &Apache::lonnet::transfer_profile_to_env($r->dir_config('lonIDsDir'),
 						     $handle);
+            if ($data{'linkprot'} ne '') {
+                my ($linkprotector,$deeplink) = split(/:/,$data{'linkprot'},2);
+                if ($deeplink ne '') {
+                    &Apache::lonnet::appenv({'request.deeplink.login' => $deeplink});
+                }
+                if ($env{'user.linkprotector'}) {
+                    my @protectors = split(/,/,$env{'user.linkprotector'});
+                    unless (grep(/^\Q$linkprotector\E$/,@protectors)) {
+                        push(@protectors,$linkprotector);
+                        @protectors = sort { $a <=> $b } @protectors;
+                        &Apache::lonnet::appenv({'user.linkprotector' => join(',',@protectors)});
+                    }
+                } else {
+                    &Apache::lonnet::appenv({'user.linkprotector' => $linkprotector });
+                }
+                if ($env{'user.linkproturi'}) {
+                    my @proturis = split(/,/,$env{'user.linkproturi'});
+                    unless(grep(/^\Q$deeplink\E$/,@proturis)) {
+                        push(@proturis,$deeplink);
+                        @proturis = sort @proturis;
+                        &Apache::lonnet::appenv({'user.linkproturi' => join(',',@proturis)});
+                    }
+                } else {
+                    &Apache::lonnet::appenv({'user.linkproturi' => $deeplink});
+                }
+            } elsif ($data{'deeplink.login'}) {
+                my $deeplink = $data{'deeplink.login'};
+                if ($data{'linkkey'}) {
+                    my $linkkey = $data{'linkkey'};
+                    if ($env{'user.deeplinkkey'}) {
+                        my @linkkeys = split(/,/,$env{'user.deeplinkkey'});
+                        unless (grep(/^\Q$linkkey\E$/,@linkkeys)) {
+                            push(@linkkeys,$linkkey);
+                            &Apache::lonnet::appenv({'user.deeplinkkey' => join(',',sort(@linkkeys))});
+                        }
+                    } else {
+                        &Apache::lonnet::appenv({'user.deeplinkkey' => $linkkey});
+                    }
+                    if ($env{'user.keyedlinkuri'}) {
+                        my @keyeduris = split(/,/,$env{'user.keyedlinkuri'});
+                        unless (grep(/^\Q$deeplink\E$/,@keyeduris)) {
+                            push(@keyeduris,$deeplink);
+                            &Apache::lonnet::appenv({'user.keyedlinkuri' => join(',',sort(@keyeduris))});
+                        }
+                    } else {
+                        &Apache::lonnet::appenv({'user.keyedlinkuri' => $deeplink});
+                    }
+                }
+                &Apache::lonnet::appenv({'request.deeplink.login' => $data{'deeplink.login'}});
+            }
             if ($data{'lti.login'}) {
                 my $needslogout;
                 if ($env{'request.lti.login'}) {
@@ -607,11 +829,41 @@ sub handler {
                         $desturl .= (($desturl =~/\?/)?'&':'?').'navmap=1';
                     }
                 }
+                if ($data{'linkprot'}) {
+                    my ($linkprotector,$linkuri) = split(/:/,$data{'linkprot'},2);
+                    if ($linkprotector) {
+                        if (ref($extra_env) eq 'HASH') {
+                            $extra_env->{'user.linkprotector'} = $linkprotector;
+                            $extra_env->{'user.linkproturi'} = $linkuri;
+                        } else {
+                            $extra_env = {'user.linkprotector' => $linkprotector,
+                                          'user.linkproturi' => $linkuri,};
+                        }
+                    }
+                } elsif ($data{'deeplink.login'}) {
+                    if ($data{'linkkey'}) {
+                        if (ref($extra_env) eq 'HASH') {
+                            $extra_env->{'user.deeplinkkey'} = $data{'linkkey'};
+                            $extra_env->{'user.keyedlinkuri'} = $data{'deeplink.login'},
+                        } else {
+                            $extra_env = {'user.deeplinkkey' => $data{'linkkey'},
+                                          'user.keyedlinkuri' => $data{'deeplink.login'}};
+                        }
+                    }
+                    if (ref($extra_env) eq 'HASH') {
+                        $extra_env->{'request.deeplink.login' => $data{'deeplink.login'}};
+                    } else {
+                        $extra_env = {'request.deeplink.login' => $data{'deeplink.login'}};
+                    }
+                }
             }
             my $skipcritical;
-            if (($data{'lti.login'}) && ($data{'lti.reqcrs'}) &&
-                ($data{'lti.reqrole'} eq 'cc')) {
-                $skipcritical = 1;
+            if ($data{'lti.login'}) {
+                if ((($data{'lti.reqcrs'}) &&
+                     ($data{'lti.reqrole'} eq 'cc')) ||
+                    ($data{'lti.selfenrollrole'})) {
+                    $skipcritical = 1;
+                }
             }
 	    &Apache::lonauth::success($r,$data{'username'},$data{'domain'},
 				      $home,$desturl,$extra_env,\%form,$skipcritical);
@@ -619,18 +871,51 @@ sub handler {
 	return OK;
     }
 
-    my $next_url='/adm/roles?selectrole=1&'.&escape($data{'role'}).'=1';
-    if ($data{'origurl'} ne '') {
-        $next_url .= '&orgurl='.&escape($data{'origurl'});
-        if ($data{'lti.login'}) {
-            if (($data{'origurl'} =~ m{/default_\d+\.sequence$}) ||
-                ($data{'origurl'} =~ m{^/res/.+\.sequence$})) {
-                $next_url .= '&navmap=1';
+    if ($data{'lti.login'}) {
+        my $handle = &Apache::lonnet::check_for_valid_session($r);
+        if ($handle) {
+            &Apache::lonnet::transfer_profile_to_env($r->dir_config('lonIDsDir'),
+                                                     $handle);
+            my $needslogout;
+            if ($env{'request.lti.login'}) {
+                if (($env{'user.name'} ne $data{'username'}) ||
+                    ($env{'user.domain'} ne $data{'domain'})) {
+                    $needslogout = 1;
+                }
+            } else {
+                $needslogout = 1;
+            }
+            if ($needslogout) {
+                &logout($r,$handle,\%data,$lti_env);
+                return OK;
             }
         }
     }
-    &Apache::lonauth::success($r,$data{'username'},$data{'domain'},$home,
-			      $next_url,$extra_env,\%form);
+
+# check if current user, and role match those expected.
+    my ($next_url,$reuse_session);
+    if (($env{'user.name'} eq $data{'username'}) && ($env{'user.domain'} eq $data{'domain'}) &&
+        ($env{'request.role'} eq $data{'role'}) && ($data{'origurl'} ne '')) {
+        $next_url = $data{'origurl'};
+        $reuse_session = 1;
+    } else {
+        $next_url='/adm/roles?selectrole=1&'.&escape($data{'role'}).'=1';
+        if ($data{'origurl'} ne '') {
+            $next_url .= '&orgurl='.&escape($data{'origurl'});
+        }
+    }
+    if ($data{'lti.login'}) {
+        if (($data{'origurl'} =~ m{/default_\d+\.sequence$}) ||
+            ($data{'origurl'} =~ m{^/res/.+\.sequence$})) {
+            $next_url .= '&navmap=1';
+        }
+    }
+    if ($reuse_session) {
+        $r->internal_redirect($next_url);
+    } else {
+        &Apache::lonauth::success($r,$data{'username'},$data{'domain'},$home,
+                                  $next_url,$extra_env,\%form);
+    }
     return OK;
 }