--- loncom/Lond.pm	2022/02/01 23:13:21	1.18
+++ loncom/Lond.pm	2022/02/16 00:06:08	1.20
@@ -1,6 +1,6 @@
 # The LearningOnline Network
 #
-# $Id: Lond.pm,v 1.18 2022/02/01 23:13:21 raeburn Exp $
+# $Id: Lond.pm,v 1.20 2022/02/16 00:06:08 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -42,6 +42,7 @@ use Crypt::OpenSSL::X509;
 use Crypt::X509::CRL;
 use Crypt::PKCS10;
 use Net::OAuth;
+use Crypt::CBC;
 
 sub dump_with_regexp {
     my ( $tail, $clientversion ) = @_;
@@ -1044,6 +1045,56 @@ sub get_dom {
     return $qresult;
 }
 
+sub store_dom {
+    my ($userinput) = @_;
+    my ($cmd,$dom,$namespace,$rid,$what) =split(/:/,$userinput);
+    my $hashref  = &tie_domain_hash($dom,$namespace,&GDBM_WRCREAT(),"S","$rid:$what") or
+        return "error: ".($!+0)." tie(GDBM) Failed while attempting $cmd";
+    $hashref->{"version:$rid"}++;
+    my $version=$hashref->{"version:$rid"};
+    my $allkeys='';
+    my @pairs=split(/\&/,$what);
+    foreach my $pair (@pairs) {
+        my ($key,$value)=split(/=/,$pair);
+        $allkeys.=$key.':';
+        $hashref->{"$version:$rid:$key"}=$value;
+    }
+    my $now = time;
+    $hashref->{"$version:$rid:timestamp"}=$now;
+    $allkeys.='timestamp';
+    $hashref->{"$version:keys:$rid"}=$allkeys;
+    &untie_user_hash($hashref) or
+        return "error: ".($!+0)." untie(GDBM) Failed while attempting $cmd";
+    return 'ok';
+}
+
+sub restore_dom {
+    my ($userinput) = @_;
+    my ($cmd,$dom,$namespace,$rid) = split(/:/,$userinput);
+    my $hashref = &tie_domain_hash($dom,$namespace,&GDBM_READER()) or
+        return "error: ".($!+0)." tie(GDBM) Failed while attempting $cmd";
+    my $qresult='';
+    if (ref($hashref)) {
+        chomp($rid);
+        my $version=$hashref->{"version:$rid"};
+        $qresult.="version=$version&";
+        my $scope;
+        for ($scope=1;$scope<=$version;$scope++) {
+            my $vkeys=$hashref->{"$scope:keys:$rid"};
+            my @keys=split(/:/,$vkeys);
+            my $key;
+            $qresult.="$scope:keys=$vkeys&";
+            foreach $key (@keys) {
+                $qresult.="$scope:$key=".$hashref->{"$scope:$rid:$key"}."&";
+            }
+        }
+        $qresult=~s/\&$//;
+    }
+    &untie_user_hash($hashref) or
+        return "error: ".($!+0)." untie(GDBM) Failed while attempting $cmd";
+    return $qresult;
+}
+
 sub crslti_itemid {
     my ($cdom,$cnum,$url,$method,$params,$loncaparev) = @_;
     unless (ref($params) eq 'HASH') {
@@ -1090,9 +1141,22 @@ sub crslti_itemid {
 
     return if (!keys(%crslti_by_key));
 
+    my %courselti = &Apache::lonnet::get_course_lti($cnum,$cdom,'provider');
+
     if (ref($crslti_by_key{$consumer_key}) eq 'ARRAY') {
         foreach my $id (@{$crslti_by_key{$consumer_key}}) {
             my $secret = $crslti{$id}{'secret'};
+            if (ref($courselti{$id}) eq 'HASH') {
+                if ((exists($courselti{$id}{'cipher'})) &&
+                    ($courselti{$id}{'cipher'} =~ /^\d+$/)) {
+                    my $keynum = $courselti{$id}{'cipher'};
+                    my $privkey = &get_dom("getdom:$cdom:private:$keynum:lti:key");
+                    if ($privkey ne '') {
+                        my $cipher = new Crypt::CBC($privkey);
+                        $secret = $cipher->decrypt_hex($secret);
+                    }
+                }
+            }
             my $request = Net::OAuth->request('request token')->from_hash($params,
                                               request_url => $url,
                                               request_method => $method,