[Oracle]使用触发器实现IP限制用户登录

在Oracle里，不像MySQL那样方便，可以直接在用户上进行IP限制，Oracle要实现用户级别的IP限制，可以使用触发器来迂回实现，下面是一个触发器的例子：

[sql] 
create or replace trigger logon_ip_control  
after logon on database  
declare  
  ip STRING(30);  
  user STRING(30);  
begin  
SELECT SYS_CONTEXT('USERENV','SESSION_USER') into user from dual;  
SELECT SYS_CONTEXT('USERENV','IP_ADDRESS') into ip from dual;  
if user='EPAY_USER'   
  THEN  
      IF ip not in ('192.168.219.20','192.168.219.22')    
      THEN raise_application_error(-20001,'User '||user||' is not allowed to connect from '||ip);  
      END IF;  
END IF;  
end;  
/

该触发器对用户EPAY_USER进行了IP限制（只允许'192.168.219.20','192.168.219.22'，如果需要设置IP段，用%或?代替即可，如'192.168.219.%‘）。

下面看几个例子测试一下：

1）从非允许IP地址登陆（192.168.219.21），连接失败

[sql] 
[oracle@lxdb2 ~]$ sqlplus epay_user@pri  
  
SQL*Plus: Release 11.2.0.3.0 Production on Wed Jul 3 19:23:48 2013  
  
Copyright (c) 1982, 2011, Oracle.  All rights reserved.  
  
Enter password:   
ERROR:  
ORA-00604: error occurred at recursive SQL level 1  
ORA-20001: User EPAY_USER is not allowed to connect from 192.168.219.21  
ORA-06512: at line 10

2）从允许IP地址登陆（192.168.219.22），连接成功

[sql] 
[oracle@lxdb1 ~]$ sqlplus epay_user  
  
SQL*Plus: Release 11.2.0.3.0 Production on Wed Jul 3 11:24:25 2013  
  
Copyright (c) 1982, 2011, Oracle.  All rights reserved.  
  
Enter password:   
  
Connected to:  
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production  
With the Partitioning, OLAP, Data Mining and Real Application Testing options

3）从本地登陆(192.168.219.23）不受IP限制影响，连接成功

[sql] 
[oracle@lxdb1 ~]$ sqlplus epay_user  
  
SQL*Plus: Release 11.2.0.3.0 Production on Wed Jul 3 11:24:25 2013  
  
Copyright (c) 1982, 2011, Oracle.  All rights reserved.  
  
Enter password:   
  
Connected to:  
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production  
With the Partitioning, OLAP, Data Mining and Real Application Testing options