md5 in pl/sql

gistfile1.sql

CREATE OR REPLACE FUNCTION md5_digest(input_string IN VARCHAR2) RETURN VARCHAR2
IS
hex_digest varchar2(32);
digest varchar2(16);
BEGIN digest := DBMS_OBFUSCATION_TOOLKIT.MD5(INPUT_STRING => input_string);
SELECT Lower(RAWTOHEX(digest)) INTO hex_digest FROM dual;
RETURN hex_digest;
END;