使用dbms_crypto包加密关键列数据

对于业务系统中常见的需要加密的列我们可以在应用层来实现，也可以在数据库层实现，
自己验证了一下使用dbms_crypto包来封装函数实现关键列的加密。

1.数据库版本

SQL> select * from v$version;

BANNER
----------------------------------------------------------------
Oracle Database 10g Enterprise Edition Release 10.2.0.4. - Prod
PL/SQL Release 10.2.0.4. - Production
CORE    10.2.0.4.      Production
TNS for Linux: Version 10.2.0.4. - Production
NLSRTL Version 10.2.0.4. - Production

2.创建加密函数

SQL> conn /as sysdba
Connected.
SQL> create or replace function fun_enable_crypto(v_str varchar2,
    v_key varchar2 default 'abcdefgh')
    return raw
    is
    --v_str_raw raw():=utl_raw.cast_to_raw(v_str);
    v_str_raw raw():=utl_i18n.string_to_raw(v_str,'AL32UTF8');
    v_key_raw raw():=utl_i18n.string_to_raw(v_key,'AL32UTF8');
    result_crypto raw();
    begin
   result_crypto:=dbms_crypto.encrypt(src=>v_str_raw,
   typ=>dbms_crypto.DES_CBC_PKCS5,
   key=>v_key_raw);
   return result_crypto;
   end;
   /

Function created.

3.创建解密函数

SQL> create or replace function fun_disable_crypto(encrypto raw,
    v_key varchar2 default 'abcdefgh')
    return varchar2
    is
    v_key_raw raw():=utl_i18n.string_to_raw(v_key,'AL32UTF8');
    result_crypto raw();
    begin
    result_crypto:=dbms_crypto.decrypt(src => encrypto,
    typ => dbms_crypto.DES_CBC_PKCS5,
   key=>v_key_raw);
   return utl_i18n.raw_to_char(result_crypto,'AL32UTF8');
   end;
   /

Function created.

3.验证加密解密

SQL> select fun_enable_crypto('中国.北京.海淀') as crypto_info from dual;

CRYPTO_INFO
--------------------------------------------------------------------------------
60E37C977B92E7C4F36FEF2BFEC55494CF57A8DB9F10FEB0

SQL> select fun_disable_crypto('60E37C977B92E7C4F36FEF2BFEC55494CF57A8DB9F10FEB0') as rel_info from dual;

REL_INFO
--------------------------------------------------------------------------------
中国.北京.海淀

--自定义一个key

SQL> select fun_enable_crypto('中国.北京.海淀','1drQdse5Nw') as crypto_info from dual;

CRYPTO_INFO
--------------------------------------------------------------------------------
D0FD950EAF47B20E331500444FD8D1090ECB7EF519750BAF

SQL> select fun_disable_crypto('D0FD950EAF47B20E331500444FD8D1090ECB7EF519750BAF','1drQdse5Nw')
    as rel_info from dual;

REL_INFO
--------------------------------------------------------------------------------
中国.北京.海淀 

参考：

http://www.xifenfei.com/5724.html
http://blog.csdn.net/rznice/article/details/7402850
http://blog.163.com/donfang_jianping/blog/static/1364739512012113053323211/