PHP Decode

 <?php 
 
      //------------------------------------------------------------------------------------ 
      function evalCrossTotal($strMD5) 
      { 
          $intTotal = 0; 
          $arrMD5Chars = str_split($strMD5, 1); 
          foreach ($arrMD5Chars as $value) 
          { 
              $intTotal += '0x0'.$value; 
          } 
          return $intTotal; 
      }//----------------------------------------------------------------------------------- 
 
 
 
      //------------------------------------------------------------------------------------ 
      function encryptString($strString, $strPassword) 
      { 
          // $strString is the content of the entire file with serials 
          $strPasswordMD5 = md5($strPassword); 
          $intMD5Total = evalCrossTotal($strPasswordMD5); 
          $arrEncryptedValues = array(); 
          $intStrlen = strlen($strString); 
          for ($i=0; $i<$intStrlen; $i++) 
          { 
              $arrEncryptedValues[] =  ord(substr($strString, $i, 1)) 
                                       +  ('0x0' . substr($strPasswordMD5, $i%32, 1)) 
                                       -  $intMD5Total; 
              $intMD5Total = evalCrossTotal(substr(md5(substr($strString,0,$i+1)), 0, 16) 
                                       .  substr(md5($intMD5Total), 0, 16)); 
          } 
          return implode(' ' , $arrEncryptedValues); 
      }//----------------------------------------------------------------------------------- 
 
    ?>