CREATE OR REPLACE procedure encdes
	(in_string IN varchar2,
	in_key IN varchar2,
	out_string OUT varchar2) as

p_in varchar2(96) := in_string;
p_out_str varchar2(96);

BEGIN
	dbms_obfuscation_toolkit.DESEncrypt(
		input_string => p_in,
		key_string =>  in_key,
		encrypted_string => p_out_str);

out_string := RAWTOHEX(UTL_RAW.CAST_TO_RAW(p_out_str));

END encdes;
/

SQL> DECLARE
  2    IN_STRING VARCHAR2(200);
  3    IN_KEY VARCHAR2(200);
  4    OUT_STRING VARCHAR2(200);
  5
  6  BEGIN
  7    IN_STRING := '1234567890123456';
  8    IN_KEY := '12345678';
  9    OUT_STRING := NULL;
 10
 11    PUBS.ENCDES ( IN_STRING, IN_KEY, OUT_STRING );
 12
 13    DBMS_OUTPUT.Put_Line('OUT_STRING = ' || OUT_STRING);
 14
 15    DBMS_OUTPUT.Put_Line('');
 16
 17    COMMIT;
 18  END;
 19  /
OUT_STRING = 96D0028878D58C896769D2A8823003EB

PL/SQL procedure successfully completed.

CREATE OR REPLACE procedure encaes
	(in_string IN varchar2,
	 in_key IN varchar2,
	 out_string OUT varchar2) as

p_in 		raw(4000);
p_key		raw(4000);
p_out_str	raw(4000);

enc_type pls_integer := DBMS_CRYPTO.ENCRYPT_AES256 + DBMS_CRYPTO.CHAIN_CBC
                          + DBMS_CRYPTO.PAD_PKCS5;

BEGIN

  p_in  := utl_i18n.string_to_raw (in_string, 'AL32UTF8');
  p_key := utl_i18n.string_to_raw (in_key,'AL32UTF8');

  p_out_str := DBMS_CRYPTO.ENCRYPT (
                src => p_in,
                key => p_key,
                typ => enc_type );

  out_string := RAWTOHEX (p_out_str);

end;
/

SQL> DECLARE
  2    IN_STRING VARCHAR2(200);
  3    IN_KEY VARCHAR2(200);
  4    OUT_STRING VARCHAR2(200);
  5
  6  BEGIN
  7    IN_STRING := '12345678901234';
  8    IN_KEY := '12345678';
  9    OUT_STRING := NULL;
 10
 11    PUBS.ENCAES ( IN_STRING, IN_KEY, OUT_STRING );
 12
 13    DBMS_OUTPUT.Put_Line('OUT_STRING = ' || OUT_STRING);
 14
 15    DBMS_OUTPUT.Put_Line('');
 16
 17    COMMIT;
 18  END;
 19  /
DECLARE
*
ERROR at line 1:
ORA-28234: key length too short
ORA-06512: at "SYS.DBMS_CRYPTO_FFI", line 3
ORA-06512: at "SYS.DBMS_CRYPTO", line 10
ORA-06512: at "TEST.ENCAES", line 18
ORA-06512: at line 11