loncom/interface/loncommon.pm - diff

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-version 1.1075.2.105, 2016/08/07 20:56:23
+version 1.1075.2.106, 2016/08/11 00:15:06
  Line 16264  sub des_decrypt {
      } else {
          $cypher=new DES $keybin;
      }
-     my $plaintext=
+     my $plaintext='';
-         $cypher->decrypt(unpack("a8",pack("H16",substr($cyphertext,0,16))));
+     my $cypherlength = length($cyphertext);
-     $plaintext.=
+     my $numchunks = int($cypherlength/32);
-         $cypher->decrypt(unpack("a8",pack("H16",substr($cyphertext,16,16))));
+     for (my $j=0; $j<$numchunks; $j++) {
-     $plaintext=substr($plaintext,1,ord(substr($plaintext,0,1)) );
+         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;
  }