--- loncom/interface/loncommon.pm	2016/08/06 20:15:00	1.1075.2.103
+++ loncom/interface/loncommon.pm	2016/08/11 00:15:06	1.1075.2.106
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # a pile of common routines
 #
-# $Id: loncommon.pm,v 1.1075.2.103 2016/08/06 20:15:00 raeburn Exp $
+# $Id: loncommon.pm,v 1.1075.2.106 2016/08/11 00:15:06 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -4683,13 +4683,13 @@ END_BLOCK
 ###############################################
 
 sub check_ip_acc {
-    my ($acc)=@_;
+    my ($acc,$clientip)=@_;
     &Apache::lonxml::debug("acc is $acc");
     if (!defined($acc) || $acc =~ /^\s*$/ || $acc =~/^\s*no\s*$/i) {
         return 1;
     }
     my $allowed=0;
-    my $ip=$env{'request.host'} || $ENV{'REMOTE_ADDR'};
+    my $ip=$env{'request.host'} || $ENV{'REMOTE_ADDR'} || $clientip;
 
     my $name;
     foreach my $pattern (split(',',$acc)) {
@@ -9872,7 +9872,9 @@ reservable_now - ref to hash of student_
 
     Keys in inner hash are:
     (a) symb: either blank or symb to which slot use is restricted.
-    (b) endreserve: end date of reservation period. 
+    (b) endreserve: end date of reservation period.
+    (c) uniqueperiod: start,end dates when slot is to be uniquely
+        selected.
 
 sorted_future - ref to array of student_schedulable slots reservable in
                 the future, ordered by start date of reservation period.
@@ -9883,6 +9885,8 @@ future_reservable - ref to hash of stude
     Keys in inner hash are:
     (a) symb: either blank or symb to which slot use is restricted.
     (b) startreserve:  start date of reservation period.
+    (c) uniqueperiod: start,end dates when slot is to be uniquely
+        selected.
 
 =back
 
@@ -9936,6 +9940,10 @@ sub get_future_slots {
             my $startreserve = $slots{$slot}->{'startreserve'};
             my $endreserve = $slots{$slot}->{'endreserve'};
             my $symb = $slots{$slot}->{'symb'};
+            my $uniqueperiod;
+            if (ref($slots{$slot}->{'uniqueperiod'}) eq 'ARRAY') {
+                $uniqueperiod = join(',',@{$slots{$slot}->{'uniqueperiod'}});
+            }
             if (($startreserve < $now) &&
                 (!$endreserve || $endreserve > $now)) {
                 my $lastres = $endreserve;
@@ -9944,13 +9952,15 @@ sub get_future_slots {
                 }
                 $reservable_now{$slot} = {
                                            symb       => $symb,
-                                           endreserve => $lastres
+                                           endreserve => $lastres,
+                                           uniqueperiod => $uniqueperiod,   
                                          };
             } elsif (($startreserve > $now) &&
                      (!$endreserve || $endreserve > $startreserve)) {
                 $future_reservable{$slot} = {
                                               symb         => $symb,
-                                              startreserve => $startreserve
+                                              startreserve => $startreserve,
+                                              uniqueperiod => $uniqueperiod,
                                             };
             }
         }
@@ -16254,11 +16264,19 @@ sub des_decrypt {
     } else {
         $cypher=new DES $keybin;
     }
-    my $plaintext=
-        $cypher->decrypt(unpack("a8",pack("H16",substr($cyphertext,0,16))));
-    $plaintext.=
-        $cypher->decrypt(unpack("a8",pack("H16",substr($cyphertext,16,16))));
-    $plaintext=substr($plaintext,1,ord(substr($plaintext,0,1)) );
+    my $plaintext='';
+    my $cypherlength = length($cyphertext);
+    my $numchunks = int($cypherlength/32);
+    for (my $j=0; $j<$numchunks; $j++) {
+        my $start = $j*32;
+        my $cypherblock = substr($cyphertext,$start,32);
+        my $chunk =
+            $cypher->decrypt(unpack("a8",pack("H16",substr($cypherblock,0,16))));
+        $chunk .=
+            $cypher->decrypt(unpack("a8",pack("H16",substr($cypherblock,16,16))));
+        $chunk=substr($chunk,1,ord(substr($chunk,0,1)) );
+        $plaintext .= $chunk;
+    }
     return $plaintext;
 }