create or replace package PG_ENCRYPT_DECRYPT
is
iKey varchar2(8):='Oracle9i';
function GEN_RAW_KEY  ( iKey in varchar2) return raw;
function DECRYPT_3KEY_MODE(iValue in raw,iMode in pls_integer)return varchar2;
function ENCRYPT_3KEY_MODE(iValue in varchar2,iMode in pls_integer)return raw;
function FormatStr(iValue in varchar2)return varchar2;
function FormatStr2(iValue in varchar2)return varchar2;
end;
/////////
create or replace package body PG_ENCRYPT_DECRYPT
is
  function GEN_RAW_KEY  ( iKey in varchar2)
  return raw
  as
    rawkey raw(240) := '';
  begin
    for i in 1..length(iKey) loop   
       rawkey := rawkeyhextoraw(to_char(ascii(substr(iKey, i, 1))));
    end loop;
    return rawkey;
  end GEN_RAW_KEY;
  /* Creating function DECRYPT_3KEY_MODE*/
  FUNCTION DECRYPT_3KEY_MODE  ( iValue in raw, iMode in pls_integer)return varchar2
  as
    vDecrypted varchar2(4000);
    rawkey raw(240) := '';
  begin
       rawkey := GEN_RAW_KEY(iKey);-- decrypt input string
       vDecrypted := dbms_obfuscation_toolkit.des3decrypt (UTL_RAW.CAST_TO_VARCHAR2(iValue), key_string => rawkey, which => iMode);
       return FormatStr2(vDecrypted);
  end DECRYPT_3KEY_MODE;
  /*Creating function ENCRYPT_3KEY_MODE*/
  FUNCTION ENCRYPT_3KEY_MODE  ( iValue in varchar2,  iMode in pls_integer)return raw
  as
    vEncrypted varchar2(4000);
    vEncryptedRaw Raw(2048);
    rawkey raw(240) := '';
  begin
    rawkey := GEN_RAW_KEY(iKey);-- encrypt input string
    vEncrypted := dbms_obfuscation_toolkit.des3encrypt (FormatStr(iValue), key_string => rawkey, which => iMode);
    -- convert to raw as out
    vEncryptedRaw := UTL_RAW.CAST_TO_RAW(vEncrypted);
    return vEncryptedRaw;
  end ENCRYPT_3KEY_MODE;
 
  function FormatStr(iValue in varchar2)return varchar2
  as
  begin
      declare
        i number;
        j number;
        m_value varchar2(4000);
      begin
           m_value:=iValue;
           i:=(length(m_value) mod 8);
           if i<>0 then
             j:=1;
             for j in 1..(8-i) loop
                 m_value:=m_value'#';
             end loop;            
           end if;
           return m_value;  
      end; 
  end FormatStr;
 
  function FormatStr2(iValue in varchar2)return varchar2
  as
  begin
      declare
        i number;
        j number;
        m_value varchar2(4000);
      begin
           m_value:=iValue;
           i:=instr(iValue,'#',1,1);
           if i>0 then
              m_value:=substr(m_value,1,i-1);
           end if;
           return m_value;  
      end; 
  end FormatStr2;
end PG_ENCRYPT_DECRYPT;
////////////
create table users1(  
userid varchar2(50)
primary key, 
passWord varchar2(4000),  --密码原文  
encrypted varchar2(4000)  --加密后的密码  
);

insert into users1 values ('user1','user1234yyyy',null);
insert into users1 values ('user2','abcd1234yy',null);
insert into users1 values ('user3','oracle12yyy',null);
update users1 set encrypted = PG_ENCRYPT_DECRYPT.ENCRYPT_3KEY_MODE(password,1);--加密
select * from users1;--正常查看
select userid,password,PG_ENCRYPT_DECRYPT.DECRYPT_3KEY_MODE(encrypted,1) DECRYPTED from users1;--解密后查看