hashes.js
function rstr(s) {
        s = (utf8) ? utf8Encode(s) : s;
        return binl2rstr(binl(rstr2binl(s), s.length * 8));
      }
function rstr(s) {
        s = (utf8) ? utf8Encode(s) : s;
        return binl2rstr(binl(rstr2binl(s), s.length * 8));
      }
function rstr ( s ) { s = ( utf8 ) ? utf8Encode ( s ) : s ; return binl2rstr ( binl ( rstr2binl ( s ) , s . length * 8 ) ) ; }
private methods 
Calculate the MD5 of a raw string
private methods Calculate the MD5 of a raw string