【方法】如何限定IP访问Oracle数据库
1.1 BLOG文档结构图
1.2 前言部分
1.2.1 导读和注意事项
各位技术爱好者,看完本文后,你可以掌握如下的技能,也可以学到一些其它你所不知道的知识,~O(∩_∩)O~:
① 限定IP访问Oracle数据库的3种方法(重点)
② 如何将信息写入到Oracle的告警日志中
③ RAISE_APPLICATION_ERROR不能抛出错误到客户端环境
④ 系统触发器
⑤ 隐含参数:_system_trig_enabled
Tips:
① 本文在itpub(http://blog.itpub.net/26736162)、博客园(http://www.cnblogs.com/lhrbest)和微信公众号(xiaomaimiaolhr)上有同步更新。
② 文章中用到的所有代码、相关软件、相关资料及本文的pdf版本都请前往小麦苗的云盘下载,小麦苗的云盘地址见:http://blog.itpub.net/26736162/viewspace-1624453/。
③ 若网页文章代码格式有错乱,请下载pdf格式的文档来阅读。
④ 在本篇BLOG中,代码输出部分一般放在一行一列的表格中。
本文若有错误或不完善的地方请大家多多指正,您的批评指正是我写作的最大动力。
1.3 本文简介
本文详细介绍了3种限制IP地址登录Oracle数据库的办法。
1.3.1 本文实验环境介绍
项目 |
source db |
db 类型 |
RAC |
db version |
11.2.0.3.0 |
db 存储 |
ASM |
OS版本及kernel版本 |
RHEL 6.5 |
数据库服务器IP地址 |
192.168.59.130 |
客户端IP地址 |
192.168.59.1或192.168.59.129 |
1.4 限定IP访问Oracle数据库的3种办法
1.4.1 利用登录触发器
1.4.1.1 简单版
SYS@orclasm > CREATE OR REPLACE TRIGGER CHK_IP_LHR 2 AFTER LOGON ON DATABASE 3 DECLARE 4 V_IPADDR VARCHAR2(30); 5 V_LOGONUSER VARCHAR2(60); 6 BEGIN 7 SELECT SYS_CONTEXT('USERENV', 'IP_ADDRESS'), 8 SYS_CONTEXT('USERENV', 'SESSION_USER') 9 INTO V_IPADDR, V_LOGONUSER 10 FROM DUAL; 11 IF V_IPADDR LIKE ('192.168.59.%') THEN 12 RAISE_APPLICATION_ERROR('-20001', 'User '||V_LOGONUSER||' is not allowed to connect from '||V_IPADDR); 13 END IF; 14 END; 15 /
Trigger created.
SYS@orclasm > create user lhr8 identified by lhr;
User created.
SYS@orclasm > grant resource,connect to lhr8;
Grant succeeded.
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客户端登录:
D:\Users\xiaomaimiao>ipconfig 以太网适配器 VMware Network Adapter VMnet8:
连接特定的 DNS 后缀 . . . . . . . : 本地链接 IPv6 地址. . . . . . . . : fe80::850a:3293:c7fb:75e1%24 IPv4 地址 . . . . . . . . . . . . : 192.168.59.1 子网掩码 . . . . . . . . . . . . : 255.255.255.0 D:\Users\xiaomaimiao>sqlplus lhr8/lhr@orclasm
SQL*Plus: Release 11.2.0.1.0 Production on Sat Mar 18 17:29:27 2017
Copyright (c) 1982, 2010, Oracle. All rights reserved.
ERROR: ORA-00604: error occurred at recursive SQL level 1 ORA-20001: User LHR8 is not allowed to connect from 192.168.59.1 ORA-06512: at line 10
Enter user-name:
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告警日志无输出。
1.4.1.2 复杂版
复杂版就是需要记录登录日志,并把报错信息输出到告警日志中。
CREATE TABLE XB_AUDIT_LOGON_LHR( ID NUMBER PRIMARY KEY, INST_ID NUMBER, OPER_DATE DATE, OS_USER VARCHAR2(255), CLIENT_IP VARCHAR2(20), CLIENT_HOSTNAME VARCHAR2(30), DB_SCHEMA VARCHAR2(30), SID NUMBER, SERIAL# NUMBER, SPID NUMBER, SESSION_TYPE VARCHAR2(1000), DATABASE_NAME VARCHAR2(255) ) NOLOGGING PARTITION BY RANGE(OPER_DATE) INTERVAL(NUMTOYMINTERVAL(1,'MONTH')) SUBPARTITION BY HASH(INST_ID) SUBPARTITION TEMPLATE ( SUBPARTITION SP1 , SUBPARTITION SP2 ) (PARTITION P201610 VALUES LESS THAN(TO_DATE('201610','YYYYMM')));
CREATE SEQUENCE S_XB_AUDIT_DDL_LHR START WITH 1 INCREMENT BY 1 CACHE 2000; SELECT S_XB_AUDIT_DDL_LHR.NEXTVAL FROM DUAL; CREATE INDEX IND_AUDIT_DDL_OS_USER ON XB_AUDIT_LOGON_LHR(OS_USER) LOCAL NOLOGGING; CREATE INDEX IND_AUDIT_DDL_SID ON XB_AUDIT_LOGON_LHR(SID,SERIAL#) LOCAL NOLOGGING;
GRANT SELECT ON XB_AUDIT_LOGON_LHR TO PUBLIC;
CREATE OR REPLACE PROCEDURE PRO_TRI_DDL_INSET_LHR AUTHID CURRENT_USER AS SP_XB_AUDIT_DDL_LHR XB_AUDIT_LOGON_LHR%ROWTYPE; V_COUNT NUMBER; V_TMP VARCHAR2(255); V_MODULE VARCHAR2(4000); V_ACTION VARCHAR2(4000); V_MESSAGE VARCHAR2(4000); BEGIN
BEGIN
SELECT A.SID, A.SERIAL#, (SELECT B.SPID FROM GV$PROCESS B WHERE B.ADDR = A.PADDR AND B.INST_ID = USERENV('INSTANCE')) SPID, UPPER(A.OSUSER) OSUSER, A.MACHINE || '--' || A.PROGRAM || '--' || A.MODULE || '--' || A.ACTION SESSION_TYPE, A.USERNAME, A.INST_ID INTO SP_XB_AUDIT_DDL_LHR.SID, SP_XB_AUDIT_DDL_LHR.SERIAL#, SP_XB_AUDIT_DDL_LHR.SPID, SP_XB_AUDIT_DDL_LHR.OS_USER, SP_XB_AUDIT_DDL_LHR.SESSION_TYPE, SP_XB_AUDIT_DDL_LHR.DB_SCHEMA, SP_XB_AUDIT_DDL_LHR.INST_ID FROM GV$SESSION A WHERE A.AUDSID = USERENV('SESSIONID') AND A.INST_ID = USERENV('INSTANCE');
--job 信息 不同的数据库这里的os_user需要修改 IF UPPER(SYS_CONTEXT('USERENV', 'OS_USER')) = 'ORACLE' THEN SELECT COUNT(1) INTO V_COUNT FROM DBA_JOBS_RUNNING A, DBA_JOBS B WHERE A.JOB = B.JOB AND A.SID = SP_XB_AUDIT_DDL_LHR.SID AND A.INSTANCE = USERENV('INSTANCE'); IF V_COUNT > 0 THEN SELECT '【DBA_JOBS:' || B.JOB || '--' || B.WHAT || '】' INTO V_TMP FROM DBA_JOBS_RUNNING A, DBA_JOBS B WHERE A.JOB = B.JOB AND A.SID = SP_XB_AUDIT_DDL_LHR.SID AND A.INSTANCE = USERENV('INSTANCE'); ELSE SELECT '--' || B.JOB_TYPE || '--' || B.JOB_ACTION INTO V_TMP FROM DBA_SCHEDULER_RUNNING_JOBS A, DBA_SCHEDULER_JOBS B WHERE A.JOB_NAME = B.JOB_NAME AND A.SESSION_ID = SP_XB_AUDIT_DDL_LHR.SID AND A.RUNNING_INSTANCE = USERENV('INSTANCE'); END IF; END IF;
EXCEPTION WHEN OTHERS THEN NULL; END;
BEGIN --v_module is much useful, "plsqldev.exe" DBMS_APPLICATION_INFO.READ_MODULE(V_MODULE, V_ACTION); V_MESSAGE := TO_CHAR(SYSDATE, 'yyyy-mm-dd hh24:mi:ss') || ' (User ' || SYS.LOGIN_USER || ' logon denied from [IP:' || ORA_CLIENT_IP_ADDRESS || ', ' || UPPER(SYS_CONTEXT('USERENV', 'OS_USER')) || '] with ' || V_MODULE || ' ' || V_ACTION || ')';
--write alert.log SYS.DBMS_SYSTEM.KSDWRT(2, V_MESSAGE); EXCEPTION WHEN OTHERS THEN NULL; END;
INSERT INTO XB_AUDIT_LOGON_LHR (ID, INST_ID, OPER_DATE, OS_USER, CLIENT_IP, CLIENT_HOSTNAME, DB_SCHEMA, SID, SERIAL#, SPID, SESSION_TYPE, DATABASE_NAME) VALUES (S_XB_AUDIT_DDL_LHR.NEXTVAL, USERENV('INSTANCE'), -- sp_xb_audit_ddl_lhr.INST_ID ora_instance_num SYSDATE, UPPER(SYS_CONTEXT('USERENV', 'OS_USER')), -- sp_xb_audit_ddl_lhr.os_user SYS_CONTEXT('userenv', 'ip_address'), --ora_client_ip_address SYS_CONTEXT('userenv', 'terminal'), --sys_context('userenv', 'host') NVL2(ORA_LOGIN_USER, SYS_CONTEXT('USERENV', 'SESSION_USER'), SP_XB_AUDIT_DDL_LHR.DB_SCHEMA), -- SYS_CONTEXT('USERENV', 'SESSION_USER') sys.login_user SP_XB_AUDIT_DDL_LHR.SID, ---- SYS_CONTEXT('USERENV', 'SID'), SP_XB_AUDIT_DDL_LHR.SERIAL#, SP_XB_AUDIT_DDL_LHR.SPID, SP_XB_AUDIT_DDL_LHR.SESSION_TYPE || V_TMP, ORA_DATABASE_NAME --sys_context('USERENV', 'DB_NAME') );
COMMIT;
EXCEPTION WHEN OTHERS THEN ROLLBACK; END PRO_TRI_DDL_INSET_LHR; /
CREATE OR REPLACE TRIGGER CHK_IP_LHR AFTER LOGON ON DATABASE DECLARE V_IPADDR VARCHAR2(30); V_LOGONUSER VARCHAR2(60); V_MODULE VARCHAR2(4000); V_ACTION VARCHAR2(4000); V_MESSAGE VARCHAR2(4000); BEGIN SELECT SYS_CONTEXT('USERENV', 'IP_ADDRESS'), SYS_CONTEXT('USERENV', 'SESSION_USER') INTO V_IPADDR, V_LOGONUSER FROM DUAL;
V_MESSAGE := TO_CHAR(SYSDATE, 'yyyy-mm-dd hh24:mi:ss') || ' (User ' || SYS.LOGIN_USER || ' logon denied from [IP:' || ORA_CLIENT_IP_ADDRESS || ', ' || UPPER(SYS_CONTEXT('USERENV', 'OS_USER')) || '] with ' || V_MODULE || ' ' || V_ACTION || ')';
IF V_IPADDR LIKE ('192.168.59.%') THEN PRO_TRI_DDL_INSET_LHR; RAISE_APPLICATION_ERROR('-20001', V_MESSAGE);
END IF; END; /
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客户端登录:
告警日志:
查询日志表:
SELECT * FROM XB_AUDIT_LOGON_LHR;
1.4.1.3 注意事项
需要注意的问题:
① 触发的对象类型可以为DATABASE,也可以为“用户名.SCHEMA”,如:
AFTER LOGON ON DATABASE
AFTER LOGON ON SCOTT.SCHEMA
② 当触发的对象类型为DATABASE的时候,登录用户不能拥有“ADMINISTER DATABASE TRIGGER”的系统权限;当触发的对象类型为“用户名.SCHEMA”的时候,登录用户不能拥有“ALTER ANY TRIGGER”的系统权限。否则,这些用户还是会正常登录到数据库,只是将相应的报错信息写入到告警日志中。所以,拥有IMP_FULL_DATABASE和DBA角色的用户以及SYS和EXFSYS用户将不能通过这种方式限制登录。
③ 隐含参数“_SYSTEM_TRIG_ENABLED”的默认值是TRUE,即允许DDL和系统触发器。当设置隐含参数“_SYSTEM_TRIG_ENABLED”为FALSE的时候,将禁用DDL和系统触发器。所以,当该值设置为FALSE的时候将不能通过这种方式限制登录。
一、 测试第二点第二点测试如下:
SYS@orclasm > grant ADMINISTER DATABASE TRIGGER to lhr8;
Grant succeeded.
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客户端登录:
D:\Users\xiaomaimiao>sqlplus lhr8/lhr@orclasm
SQL*Plus: Release 11.2.0.1.0 Production on Sat Mar 18 18:33:13 2017
Copyright (c) 1982, 2010, Oracle. All rights reserved.
Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production With the Partitioning, Automatic Storage Management, OLAP, Data Mining and Real Application Testing options
LHR8@orclasm>
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告警日志:
Sat Mar 18 18:33:13 2017 2017-03-18 18:33:13 (User LHR8 logon denied from [IP:192.168.59.1, XIAOMAIMIAO] with sqlplus.exe ) Errors in file /u01/app/oracle/diag/rdbms/orclasm/orclasm/trace/orclasm_ora_33505.trc: ORA-00604: error occurred at recursive SQL level 1 ORA-20001: 2017-03-18 18:33:13 (User LHR8 logon denied from [IP:192.168.59.1, XIAOMAIMIAO] with ) ORA-06512: at line 21
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继续测试:
SYS@orclasm > revoke ADMINISTER DATABASE TRIGGER from lhr8;
Revoke succeeded.
SYS@orclasm > GRANT ALTER ANY TRIGGER TO LHR8;
Grant succeeded.
SYS@orclasm >
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客户端继续登录,发现不能正常登录。将触发器中的AFTER LOGON ON DATABASE修改为AFTER LOGON ON LHR8.SCHEMA,其他不变,继续测试:
发现可以正常登录了,告警日志:
二、 测试第三点
将触发器中的AFTER LOGON ON LHR8.SCHEMA修改为AFTER LOGON ON DATABASE,其他不变,继续测试:
不能正常登录,下面禁用系统触发器:
SYS@orclasm > set pagesize 9999 SYS@orclasm > set line 9999 SYS@orclasm > col NAME format a40 SYS@orclasm > col KSPPDESC format a50 SYS@orclasm > col KSPPSTVL format a20 SYS@orclasm > SELECT a.INDX, 2 a.KSPPINM NAME, 3 a.KSPPDESC, 4 b.KSPPSTVL 5 FROM x$ksppi a, 6 x$ksppcv b 7 WHERE a.INDX = b.INDX 8 and lower(a.KSPPINM) like lower('%?meter%'); Enter value for parameter: _system_trig_enabled old 8: and lower(a.KSPPINM) like lower('%?meter%') new 8: and lower(a.KSPPINM) like lower('%_system_trig_enabled%')
INDX NAME KSPPDESC KSPPSTVL ---------- ---------------------------------------- -------------------------------------------------- -------------------- 1750 _system_trig_enabled are system triggers enabled TRUE
SYS@orclasm > alter system set "_system_trig_enabled"=false;
System altered.
SYS@orclasm >
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进行登录:
发现可以正常登录了。将参数"_system_trig_enabled"修改回原值。
SYS@orclasm > alter system set "_system_trig_enabled"=true;
System altered.
SYS@orclasm > alter system reset "_system_trig_enabled" scope=spfile sid='*';
System altered.
SYS@orclasm >
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1.4.1.4 利用登录触发器实现时间段登录
Use Event Triggers
------------------
If you allow the users to log in the database only from Monday to Friday included,
and from 8AM to 6PM, create an event trigger that checks after logon on
database for each user (except the DBA users) that the connection occurs only
within this timeframe.
Example 1
-------
1. No check set up yet: any ordinary user can log into the database:
SQL> connect test_trigger/test_trigger
Connected.
2. The DBA creates an event trigger that checks if the connection occurs
between Monday and Friday , and within working hours: 8AM to 6PM.
SQL> connect system/manager Connected. SQL> create or replace trigger logon_trg after logon on database begin if (to_char(sysdate,'D') not between '2' and '6') or (to_char(sysdate, 'HH24') not between '08' and '18') then RAISE_APPLICATION_ERROR(-20001, 'You are not allowed to log into database now.'); end if; end; /
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Trigger created.
3. It is Friday 5PM : an ordinary user can log into the database:
SQL> connect test_trigger/test_trigger Connected.
It is Monday 7AM : an ordinary user cannot log into the database It is Saturday 9AM : an ordinary user cannot log into the database:
SQL> connect test_trigger/test_trigger ERROR: ORA-00604: error occurred at recursive SQL level 1 ORA-20001: You are not allowed to log into database now. ORA-06512: at line 3
Warning: You are no longer connected to ORACLE. SQL>
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Example 2
-------
Another example to restrict the logon periods for a users so that they can only
access the database betrween the periods to 17:00 - 24:00 daily.
If the user attempts to logon during a period outside of this range his logon
attempt will fail:
SQL> CREATE OR REPLACE TRIGGER ScottLoginTrigger after logon on scott.schema declare temp varchar2(50); v_time varchar2(50); begin temp := 'select to_char(sysdate,''HH24:MI'') from dual'; EXECUTE IMMEDIATE temp into v_time; if (to_date(v_time,'HH24:MI') < to_date('17:00','HH24:MI')) then raise_application_error (-20001,'SCOTT access is denied until 17:00. The current time is '||v_time,true); end if; if (to_date(v_time,'HH24:MI') > to_date('23:59','HH24:MI')) then raise_application_error (-20001,'SCOTT access is denied because the time is past 23:59. The current time is '||v_time,true); end if; end; /
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However, users with ADMINISTER DATABASE TRIGGER system privilege can log into
the database any time.
1.4.2 利用sqlnet.ora
第二种是修改$ORACLE_HOME/network/admin/sqlnet.ora文件,增加如下内容:
TCP.VALIDNODE_CHECKING=YES #开启IP限制功能 TCP.INVITED_NODES=(127.0.0.1,IP1,IP2,……) #允许访问数据库的IP地址列表,多个IP地址使用逗号分开 TCP.EXCLUDED_NODES=(IP1,IP2,……) #禁止访问数据库的IP地址列表,多个IP地址使用逗号分开 |
之后重新启动监听器即可。这样客户端在登录的时候会报“ORA-12537: TNS:connection closed”的错误。
需要注意的问题:
① 需要设置参数TCP.VALIDNODE_CHECKING为YES才能激活该特性。
② 一定要许可或不要禁止数据库服务器本机的IP地址,否则通过lsnrctl将不能启动或停止监听,因为该过程监听程序会通过本机的IP访问监听器,而该IP被禁止了,但是通过服务启动或关闭则不影响。
③ 当参数TCP.INVITED_NODES和TCP.EXCLUDED_NODES设置的地址相同的时候以TCP.INVITED_NODES的配置为主。
④ 修改之后,一定要重起监听才能生效,而不需要重新启动数据库。
⑤ 这个方式只是适合TCP/IP协议。
⑥ 这个配置适用于Oracle 9i以上版本。在Oracle 9i之前的版本使用文件protocol.ora。
⑦ 在服务器上直接连接数据库不受影响。
⑧ 这种限制方式是通过监听器来限制的。
⑨ 这个限制只是针对IP检测,对于用户名检测是不支持的。
删除之前创建的触发器,继续测试。
[grid@rhel6lhr ~]$ more $ORACLE_HOME/network/admin/sqlnet.ora # sqlnet.ora Network Configuration File: /u01/app/grid/11.2.0/network/admin/sqlnet.ora # Generated by Oracle configuration tools.
NAMES.DIRECTORY_PATH= (TNSNAMES, EZCONNECT)
ADR_BASE = /u01/app/grid TCP.VALIDNODE_CHECKING=YES TCP.INVITED_NODES=(127.0.0.1,192.168.59.130,192.168.59.1,192.168.59.2) TCP.EXCLUDED_NODES=(172.168.*) [grid@rhel6lhr ~]$
|
重启监听:
[grid@rhel6lhr ~]$ lsnrctl reload
LSNRCTL for Linux: Version 11.2.0.3.0 - Production on 18-MAR-2017 18:55:54
Copyright (c) 1991, 2011, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=192.168.59.130)(PORT=1521))) The command completed successfully [grid@rhel6lhr ~]$
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客户端连接:
[oracle@orcltest ~]$ ip a | grep eth0 4: eth0: mtu 1500 qdisc pfifo_fast state UP qlen 1000 inet 192.168.59.129/24 brd 192.168.59.255 scope global eth0 [oracle@orcltest ~]$ sqlplus lhr8/lhr@192.168.59.130/orclasm.lhr.com
SQL*Plus: Release 11.2.0.3.0 Production on Sat Mar 18 18:57:43 2017
Copyright (c) 1982, 2011, Oracle. All rights reserved.
ERROR: ORA-12537: TNS:connection closed
Enter user-name:
|
监听报错:
Sat Mar 18 18:58:44 2017 18-MAR-2017 18:58:44 * 12546 TNS-12546: TNS:permission denied TNS-12560: TNS:protocol adapter error TNS-00516: Permission denied |
使用192.168.59.1客户端进行登录:
D:\Users\xiaomaimiao>sqlplus lhr8/lhr@192.168.59.130/orclasm.lhr.com
SQL*Plus: Release 11.2.0.1.0 Production on Sat Mar 18 19:00:15 2017
Copyright (c) 1982, 2010, Oracle. All rights reserved.
Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production With the Partitioning, Automatic Storage Management, OLAP, Data Mining and Real Application Testing options
LHR8@192.168.59.130/orclasm.lhr.com>
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发现可以正常登录。将TCP.INVITED_NODES的IP里加入192.168网段,则可以正常登录:
[grid@rhel6lhr ~]$ more $ORACLE_HOME/network/admin/sqlnet.ora # sqlnet.ora Network Configuration File: /u01/app/grid/11.2.0/network/admin/sqlnet.ora # Generated by Oracle configuration tools.
NAMES.DIRECTORY_PATH= (TNSNAMES, EZCONNECT)
ADR_BASE = /u01/app/grid TCP.VALIDNODE_CHECKING=YES TCP.INVITED_NODES=(127.0.0.1,192.168.59.130,192.168.59.1,192.168.59.2,192.168.*) TCP.EXCLUDED_NODES=(172.168.*)
|
客户端登录:
[oracle@orcltest ~]$ sqlplus lhr8/lhr@192.168.59.130/orclasm.lhr.com
SQL*Plus: Release 11.2.0.3.0 Production on Sat Mar 18 19:03:27 2017
Copyright (c) 1982, 2011, Oracle. All rights reserved.
Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production With the Partitioning, Automatic Storage Management, OLAP, Data Mining and Real Application Testing options
LHR8@192.168.59.130/orclasm.lhr.com>
|
1.4.3 利用防火墙
第3种是修改数据库服务器的IPTABLES(配置文件:/etc/sysconfig/iptables)来限制某些IP登录数据库服务器。如下:
iptables -I INPUT -s 192.168.59.129 -j DROP service iptables save |
则,192.168.59.129这台主机将不能连接到数据库服务器了,会报“ORA-12170: TNS:Connect timeout occurred”的错误。
测试:
[oracle@orcltest ~]$ sqlplus lhr8/lhr@192.168.59.130/orclasm.lhr.com
SQL*Plus: Release 11.2.0.3.0 Production on Sat Mar 18 19:19:23 2017
Copyright (c) 1982, 2011, Oracle. All rights reserved.
ERROR: ORA-12170: TNS:Connect timeout occurred
Enter user-name:
[oracle@orcltest ~]$ tnsping 192.168.59.130/orclasm.lhr.com
TNS Ping Utility for Linux: Version 11.2.0.3.0 - Production on 18-MAR-2017 19:18:16
Copyright (c) 1997, 2011, Oracle. All rights reserved.
Used parameter files: /u02/app/oracle/product/11.2.0/dbhome_1/network/admin/sqlnet.ora
Used EZCONNECT adapter to resolve the alias Attempting to contact (DESCRIPTION=(CONNECT_DATA=(SERVICE_NAME=orclasm.lhr.com))(ADDRESS=(PROTOCOL=TCP)(HOST=192.168.59.130)(PORT=1521))) ^C [oracle@orcltest ~]$ ping 192.168.59.130 PING 192.168.59.130 (192.168.59.130) 56(84) bytes of data. ^C --- 192.168.59.130 ping statistics --- 3 packets transmitted, 0 received, 100% packet loss, time 2136ms
[oracle@orcltest ~]$
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该部分可以参考网络配置,小麦苗从网上找了很多。
我们可以通过以下的iptables的设置来限制用户访问oracle所在linux操作系统的安全。
1、清楚操作系统默认的iptables策略
我本机安装的是centos6.0,安装之后系统会提供iptables默认的policy策略,我们首先要清楚默认的策略
iptables -F
2、开发22和1521端口对局域网的某个IP,在本例中客户端ip是192.168.1.125,oracle所在机器的IP是192.168.1.144,在这里,设置仅有该客户端可以访问22和1521端口,局域网内的其他IP都不允许访问,
iptables -A INPUT -s 192.168.1.125/32 -i eth0 -p tcp --dport 22 -j ACCEPT
iptables -A INPUT -s 192.168.1.125/32 -i eth0 -p tcp --dport 1521 -j ACCEPT
iptables -A INPUT -s 192.168.1.0/24 -p tcp --dport 22 -j DROP
iptables -A INPUT -s 192.168.1.0/24 -p tcp --dport 1521 -j DROP
这样同一网段内除192.168.1.125之外其他IP都不能访问数据库服务器,即使ping命令也不可以
3、开发22和1521的OUTPUT链给192.168.1.125,否则已经启动的oracle instance的pmon进程无法动态注册到1521端口中
iptables -A OUTPUT -d 192.168.1.125/32 -p tcp --sport 22 -j ACCEPT
iptables -A OUTPUT -d 192.168.1.125/32 -p tcp --sport 1521 -j ACCEPT
4、保存当前设置的iptables规则
service iptables save
这时系统会将已经设置的规则保存到/etc/sysconfig/iptables文件中
否则重启之后之前设置的规则都会失效
先关闭所有的80端口
开启ip段192.168.1.0/24端的80口
开启ip段211.123.16.123/24端ip段的80口
# iptables -I INPUT -p tcp --dport 80 -j DROP
# iptables -I INPUT -s 192.168.1.0/24 -p tcp --dport 80 -j ACCEPT
# iptables -I INPUT -s 211.123.16.123/24 -p tcp --dport 80 -j ACCEPT
以上是临时设置。
1.先备份iptables
# cp /etc/sysconfig/iptables /var/tmp
2.然后保存iptables
# service iptables save
3.重启防火墙
#service iptables restart
以下是端口,先全部封再开某些的IP
iptables -I INPUT -p tcp --dport 9889 -j DROP
iptables -I INPUT -s 192.168.1.0/24 -p tcp --dport 9889 -j ACCEPT
如果用了NAT转发记得配合以下才能生效
iptables -I FORWARD -p tcp --dport 80 -j DROP
iptables -I FORWARD -s 192.168.1.0/24 -p tcp --dport 80 -j ACCEPT
常用的IPTABLES规则如下:
只能收发邮件,别的都关闭
iptables -I Filter -m mac --mac-source 00:0F:EA:25:51:37 -j DROP
iptables -I Filter -m mac --mac-source 00:0F:EA:25:51:37 -p udp --dport 53 -j ACCEPT
iptables -I Filter -m mac --mac-source 00:0F:EA:25:51:37 -p tcp --dport 25 -j ACCEPT
iptables -I Filter -m mac --mac-source 00:0F:EA:25:51:37 -p tcp --dport 110 -j ACCEPT
IPSEC NAT 策略
iptables -I PFWanPriv -d 192.168.100.2 -j ACCEPT
iptables -t nat -A PREROUTING -p tcp --dport 80 -d $INTERNET_ADDR -j DNAT --to-destination 192.168.100.2:80
iptables -t nat -A PREROUTING -p tcp --dport 1723 -d $INTERNET_ADDR -j DNAT --to-destination 192.168.100.2:1723
iptables -t nat -A PREROUTING -p udp --dport 1723 -d $INTERNET_ADDR -j DNAT --to-destination 192.168.100.2:1723
iptables -t nat -A PREROUTING -p udp --dport 500 -d $INTERNET_ADDR -j DNAT --to-destination 192.168.100.2:500
iptables -t nat -A PREROUTING -p udp --dport 4500 -d $INTERNET_ADDR -j DNAT --to-destination 192.168.100.2:4500
FTP服务器的NAT
iptables -I PFWanPriv -p tcp --dport 21 -d 192.168.100.200 -j ACCEPT
iptables -t nat -A PREROUTING -p tcp --dport 21 -d $INTERNET_ADDR -j DNAT --to-destination 192.168.100.200:21
只允许访问指定网址
iptables -A Filter -p udp --dport 53 -j ACCEPT
iptables -A Filter -p tcp --dport 53 -j ACCEPT
iptables -A Filter -d www.3322.org -j ACCEPT
iptables -A Filter -d img.cn99.com -j ACCEPT
iptables -A Filter -j DROP
开放一个IP的一些端口,其它都封闭
iptables -A Filter -p tcp --dport 80 -s 192.168.100.200 -d www.pconline.com.cn -j ACCEPT
iptables -A Filter -p tcp --dport 25 -s 192.168.100.200 -j ACCEPT
iptables -A Filter -p tcp --dport 109 -s 192.168.100.200 -j ACCEPT
iptables -A Filter -p tcp --dport 110 -s 192.168.100.200 -j ACCEPT
iptables -A Filter -p tcp --dport 53 -j ACCEPT
iptables -A Filter -p udp --dport 53 -j ACCEPT
iptables -A Filter -j DROP
多个端口
iptables -A Filter -p tcp -m multiport --destination-port 22,53,80,110 -s 192.168.20.3 -j REJECT
连续端口
iptables -A Filter -p tcp -m multiport --source-port 22,53,80,110 -s 192.168.20.3 -j REJECT iptables -A Filter -p tcp --source-port 2:80 -s 192.168.20.3 -j REJECT
指定时间上网
iptables -A Filter -s 10.10.10.253 -m time --timestart 6:00 --timestop 11:00 --days Mon,Tue,Wed,Thu,Fri,Sat,Sun -j DROP
iptables -A Filter -m time --timestart 12:00 --timestop 13:00 --days Mon,Tue,Wed,Thu,Fri,Sat,Sun -j ACCEPT
iptables -A Filter -m time --timestart 17:30 --timestop 8:30 --days Mon,Tue,Wed,Thu,Fri,Sat,Sun -j ACCEPT
禁止多个端口服务
iptables -A Filter -m multiport -p tcp --dport 21,23,80 -j ACCEPT
将WAN 口NAT到PC
iptables -t nat -A PREROUTING -i $INTERNET_IF -d $INTERNET_ADDR -j DNAT --to-destination 192.168.0.1
将WAN口8000端口NAT到192。168。100。200的80端口
iptables -t nat -A PREROUTING -p tcp --dport 8000 -d $INTERNET_ADDR -j DNAT --to-destination 192.168.100.200:80
MAIL服务器要转的端口
iptables -t nat -A PREROUTING -p tcp --dport 110 -d $INTERNET_ADDR -j DNAT --to-destination 192.168.100.200:110
iptables -t nat -A PREROUTING -p tcp --dport 25 -d $INTERNET_ADDR -j DNAT --to-destination 192.168.100.200:25
只允许PING 202。96。134。133,别的服务都禁止
iptables -A Filter -p icmp -s 192.168.100.200 -d 202.96.134.133 -j ACCEPT
iptables -A Filter -j DROP
禁用BT配置
iptables –A Filter –p tcp –dport 6000:20000 –j DROP
禁用QQ防火墙配置
iptables -A Filter -p udp --dport ! 53 -j DROP
iptables -A Filter -d 218.17.209.0/24 -j DROP
iptables -A Filter -d 218.18.95.0/24 -j DROP
iptables -A Filter -d 219.133.40.177 -j DROP
基于MAC,只能收发邮件,其它都拒绝
iptables -I Filter -m mac --mac-source 00:0A:EB:97:79:A1 -j DROP
iptables -I Filter -m mac --mac-source 00:0A:EB:97:79:A1 -p tcp --dport 25 -j ACCEPT
iptables -I Filter -m mac --mac-source 00:0A:EB:97:79:A1 -p tcp --dport 110 -j ACCEPT
禁用MSN配置
iptables -A Filter -p udp --dport 9 -j DROP
iptables -A Filter -p tcp --dport 1863 -j DROP
iptables -A Filter -p tcp --dport 80 -d 207.68.178.238 -j DROP
iptables -A Filter -p tcp --dport 80 -d 207.46.110.0/24 -j DROP
只允许PING 202。96。134。133 其它公网IP都不许PING
iptables -A Filter -p icmp -s 192.168.100.200 -d 202.96.134.133 -j ACCEPT
iptables -A Filter -p icmp -j DROP
禁止某个MAC地址访问internet:
iptables -I Filter -m mac --mac-source 00:20:18:8F:72:F8 -j DROP
禁止某个IP地址的PING:
iptables –A Filter –p icmp –s 192.168.0.1 –j DROP
禁止某个IP地址服务:
iptables –A Filter -p tcp -s 192.168.0.1 --dport 80 -j DROP
iptables –A Filter -p udp -s 192.168.0.1 --dport 53 -j DROP
只允许某些服务,其他都拒绝(2条规则)
iptables -A Filter -p tcp -s 192.168.0.1 --dport 1000 -j ACCEPT
iptables -A Filter -j DROP
禁止某个IP地址的某个端口服务
iptables -A Filter -p tcp -s 10.10.10.253 --dport 80 -j ACCEPT
iptables -A Filter -p tcp -s 10.10.10.253 --dport 80 -j DROP
禁止某个MAC地址的某个端口服务
iptables -I Filter -p tcp -m mac --mac-source 00:20:18:8F:72:F8 --dport 80 -j DROP
禁止某个MAC地址访问internet:
iptables -I Filter -m mac --mac-source 00:11:22:33:44:55 -j DROP
禁止某个IP地址的PING:
iptables –A Filter –p icmp –s 192.168.0.1 –j DROP
1.5 本文总结
在Oracle中,有3种办法可以限定特定IP访问数据库。第一种是利用登录触发器,如下:
CREATE OR REPLACE TRIGGER CHK_IP_LHR AFTER LOGON ON DATABASE DECLARE V_IPADDR VARCHAR2(30); V_LOGONUSER VARCHAR2(60); BEGIN SELECT SYS_CONTEXT('USERENV', 'IP_ADDRESS'), SYS_CONTEXT('USERENV', 'SESSION_USER') INTO V_IPADDR, V_LOGONUSER FROM DUAL; IF V_IPADDR LIKE ('192.168.59.%') THEN RAISE_APPLICATION_ERROR('-20001', 'User '||V_LOGONUSER||' is not allowed to connect from '||V_IPADDR); END IF; END; / |
需要注意的问题:
① 触发的对象类型可以为DATABASE,也可以为“用户名.SCHEMA”,如:
AFTER LOGON ON DATABASE AFTER LOGON ON SCOTT.SCHEMA |
② 当触发的对象类型为DATABASE的时候,登录用户不能拥有“ADMINISTER DATABASE TRIGGER”的系统权限;当触发的对象类型为“用户名.SCHEMA”的时候,登录用户不能拥有“ALTER ANY TIGGER”的系统权限。否则,这些用户还是会正常登录到数据库,只是将相应的报错信息写入到告警日志中。所以,拥有IMP_FULL_DATABASE和DBA角色的用户以及SYS和EXFSYS用户将不能通过这种方式限制登录。
③ 隐含参数“_SYSTEM_TRIG_ENABLED”的默认值是TRUE,即允许DDL和系统触发器。当设置隐含参数“_SYSTEM_TRIG_ENABLED”为FALSE的时候,将禁用DDL和系统触发器。所以,当该值设置为FALSE的时候将不能通过这种方式限制登录。
第二种是修改$ORACLE_HOME/network/admin/sqlnet.ora文件,增加如下内容:
TCP.VALIDNODE_CHECKING=YES #开启IP限制功能 TCP.INVITED_NODES=(127.0.0.1,IP1,IP2,……) #允许访问数据库的IP地址列表,多个IP地址使用逗号分开 TCP.EXCLUDED_NODES=(IP1,IP2,……) #禁止访问数据库的IP地址列表,多个IP地址使用逗号分开 |
之后重新启动监听器即可。这样客户端在登录的时候会报“ORA-12537: TNS:connection closed”的错误。
需要注意的问题:
① 需要设置参数TCP.VALIDNODE_CHECKING为YES才能激活该特性。
② 一定要许可或不要禁止数据库服务器本机的IP地址,否则通过lsnrctl将不能启动或停止监听,因为该过程监听程序会通过本机的IP访问监听器,而该IP被禁止了,但是通过服务启动或关闭则不影响。
③ 当参数TCP.INVITED_NODES和TCP.EXCLUDED_NODES设置的地址相同的时候以TCP.INVITED_NODES的配置为主。
④ 修改之后,一定要重起监听才能生效,而不需要重新启动数据库。
⑤ 这个方式只是适合TCP/IP协议。
⑥ 这个配置适用于Oracle 9i以上版本。在Oracle 9i之前的版本使用文件protocol.ora。
⑦ 在服务器上直接连接数据库不受影响。
⑧ 这种限制方式是通过监听器来限制的。
⑨ 这个限制只是针对IP检测,对于用户名检测是不支持的。
第3种是修改数据库服务器的IPTABLES(配置文件:/etc/sysconfig/iptables)来限制某些IP登录数据库服务器。如下:
iptables -A INPUT -s 192.168.59.1/32 -i eth0 -p tcp --dport 1521 -j DROP service iptables save |
则,192.168.59.1这台主机将不能通过1521端口连接到数据库服务器了,会报“ORA-12170: TNS:Connect timeout occurred”的错误。
1.6 参考
1.6.1 MOS
1.6.1.1 Connecting as DBA Does not Fire RAISE_APPLICATION_ERROR in a AFTER LOGON ON DATABASE TRIGGER (文档 ID 226058.1)
APPLIES TO:
Oracle Database - Enterprise Edition - Version 8.1.7.4 to 11.2.0.2 [Release 8.1.7 to 11.2]Information in this document applies to any platform.
***Checked for relevance on 03-Aug-2016***
SYMPTOMS
TRIGGER AFTER LOGON ON DATABASE does not fire
Login as a user with DBA privileges
ORA-00604: error occurred at recursive SQL level %s
ORA-06512: at %sline %s
CAUSE
Documented and expected behavior.
SOLUTION
Oracel Database 11.2:
Oracle? Database PL/SQL Language Reference 11g Release 2 (11.2)
Chapter 9 PL/SQL Triggers
Exception Handling in Triggers
In the following cases, the database rolls back only the effects of the trigger, not the effects of the triggering statement (and logs the error in trace files and the alert log):
The triggering event is either AFTER STARTUP ON DATABASE or BEFORE SHUTDOWN ON DATABASE.
The triggering event is AFTER LOGON ON DATABASE and the user has the ADMINISTER DATABASE TRIGGER privilege.
The triggering event is AFTER LOGON ON SCHEMA and the user either owns the schema or has the ALTER ANY TRIGGER privilege.
Oracle Server 11.1:
Oracle Database PL/SQL Language Reference 11g Release 1
Chapter: Using Triggers
Section: Error Conditions and Exceptions in the Trigger Body
If a predefined or user-defined error condition or exception is raised during the execution of a trigger body, then all effects of the trigger body, as well as the triggering statement, are rolled back (unless the error is trapped by an exception handler). Therefore, a trigger body can prevent the execution of the triggering statement by raising an exception. User-defined exceptions are commonly used in triggers that enforce complex security authorizations or integrity constraints.
The only exception to this is when the event under consideration is database STARTUP, SHUTDOWN, or LOGIN when the user logging in is SYSTEM. In these scenarios, only the trigger action is rolled back.
REFERENCES
BUG:1415194 - RAISE_APPLICATION_ERROR DOES NOT RAISE AN EXCEPTION INSIDE A AFTER LOGON TRIGGERhttp://docs.oracle.com/cd/E11882_01/appdev.112/e25519/triggers.htm#CIHGJCFI
http://docs.oracle.com/cd/B28359_01/appdev.111/b28370/triggers.htm#autoId33
1.6.1.2 How to Prevent Users From Log Into a Database Within Defined Periods (文档 ID 220491.1)
PURPOSE
-------
This document explains how to set up the database security so that users cannot
log into the database outside defined time-window.
SCOPE & APPLICATION
-------------------
For DBAs who need to prevent users from log into the database outside defined
time periods.
Use Event Triggers
------------------
If you allow the users to log in the database only from Monday to Friday included,
and from 8AM to 6PM, create an event trigger that checks after logon on
database for each user (except the DBA users) that the connection occurs only
within this timeframe.
Example 1
-------
1. No check set up yet: any ordinary user can log into the database:
SQL> connect test_trigger/test_trigger
Connected.
2. The DBA creates an event trigger that checks if the connection occurs
between Monday and Friday , and within working hours: 8AM to 6PM.
SQL> connect system/manager
Connected.
SQL> create or replace trigger logon_trg after logon on database
begin
if (to_char(sysdate,'D') not between '2' and '6')
or (to_char(sysdate, 'HH24') not between '08' and '18') then
RAISE_APPLICATION_ERROR(-20001, 'You are not allowed to log into
database now.');
end if;
end;
/
Trigger created.
3. It is Friday 5PM : an ordinary user can log into the database:
SQL> connect test_trigger/test_trigger
Connected.
It is Monday 7AM : an ordinary user cannot log into the database
It is Saturday 9AM : an ordinary user cannot log into the database:
SQL> connect test_trigger/test_trigger
ERROR:
ORA-00604: error occurred at recursive SQL level 1
ORA-20001: You are not allowed to log into database now.
ORA-06512: at line 3
Warning: You are no longer connected to ORACLE.
SQL>
Example 2
-------
Another example to restrict the logon periods for a users so that they can only
access the database betrween the periods to 17:00 - 24:00 daily.
If the user attempts to logon during a period outside of this range his logon
attempt will fail:
SQL> CREATE OR REPLACE TRIGGER ScottLoginTrigger after logon on scott.schema
declare
temp varchar2(50);
v_time varchar2(50);
begin
temp := 'select to_char(sysdate,''HH24:MI'') from dual';
EXECUTE IMMEDIATE temp into v_time;
if (to_date(v_time,'HH24:MI') < to_date('17:00','HH24:MI')) then
raise_application_error (-20001,'SCOTT access is denied until 17:00. The current time is '||v_time,true);
end if;
if (to_date(v_time,'HH24:MI') > to_date('23:59','HH24:MI')) then
raise_application_error (-20001,'SCOTT access is denied because the time is past 23:59. The current time is '||v_time,true);
end if;
end;
/
However, users with ADMINISTER DATABASE TRIGGER system privilege can log into
the database any time.
RELATED DOCUMENTS
----------------- Note:70679.1 How to Audit Logon/Logoff Events with Triggers
1.6.1.3 ADMINISTER DATABASE TRIGGER Privilege Causes Logon Trigger to Skip Errors (文档 ID 265012.1)
***Checked for relevance on 02-Oct-2012***
PURPOSE
-------
This bulletin explains which effect the system privilege ADMINISTER DATABASE
TRIGGER has on database triggers when errors are raised.
Similarly, ALTER ANY TRIGGER system privilege causes schema logon triggers to be
skipped on errors.
SCOPE & APPLICATION
-------------------
For DBAs who set up database access control using logon triggers.
ADMINISTER DATABASE TRIGGER Privilege Behavior with Database Logon Trigger
--------------------------------------------------------------------------
Logon triggers can be used to mediate database access: when the restrictive
conditions are not met, an application error with a message is raised that
causes the logon to be denied.
create or replace trigger on_logon
after logon on database
begin
if USER='TEST' then
raise_application_error(-20002,'LOGON ERROR',true);
end if;
end;
/
If user TEST connects, he is rejected:
SQL> connect test/test
ERROR:
ORA-00604: error occurred at recursive SQL level 1
ORA-20002: LOGON ERROR
ORA-06512: at line 21
Warning: You are no longer connected to ORACLE.
However, we need to keep at least one user who can still connect when there is
a problem : a fallback mechanism must exist where an administrative user is
exempt from such errors of a prohibited connection.
Any user granted the ADMINISTER DATABASE TRIGGER system privilege can still
connect : instead of getting the error causing the session to be terminated,
the error is recorded in the alert.log and a trace file in user_dump_dest.
SQL> connect / as sysdba
Connected.
SQL> grant ADMINISTER DATABASE TRIGGER to TEST;
Grant succeeded.
SQL> connect test/test
Connected.
In alert.log :
Fri Mar 5 12:17:08 2004
Errors in file /ots2/app/oracle/admin/v920/udump/v920_ora_7682.trc:
ORA-00604: error occurred at recursive SQL level 1
ORA-20002: LOGON ERROR
ORA-06512: at line 21
In trace file :
*** SESSION ID:(15.76) 2004-03-05 12:17:08.750
Skipped error 604 during the execution of SYS.ON_LOGON
*** 2004-03-05 12:17:08.768
ksedmp: internal or fatal error
ORA-00604: error occurred at recursive SQL level 1
ORA-20002: LOGON ERROR
ORA-06512: at line 21
The ADMINISTER DATABASE TRIGGER is by default granted to the following users and
roles (are not listed the options' schemas) :
SQL> select grantee from dba_sys_privs
2 where privilege='ADMINISTER DATABASE TRIGGER';
GRANTEE
------------------------------
DBA --> role
SYS --> user
IMP_FULL_DATABASE --> role
EXFSYS --> user
ALTER ANY TIGGER Privilege Behavior with Schema Logon Trigger
-------------------------------------------------------------
Similarly, if the logon trigger is on SCHEMA and the current user is not the
owner, ALTER ANY TRIGGER privilege is required to be able to connect.
connect system/manager
create or replace trigger on_logon
after logon on TEST.schema
begin
raise_application_error(-20002,'LOGON ERROR',true);
end;
/
SQL> connect test/test
ERROR:
ORA-00604: error occurred at recursive SQL level 1
ORA-20002: LOGON ERROR
ORA-06512: at line 2
Warning: You are no longer connected to ORACLE.
SQL> conn system/manager
Connected.
SQL> grant alter any trigger to test;
Grant succeeded.
SQL> conn test/test
Connected.
Triggers owned by SYS and O7_DICTIONARY_ACCESSIBILITY
-----------------------------------------------------
Note that in the above example, the schema trigger is actually owned by user SYSTEM,
this means when user TEST has the ALTER ANY TRIGGER privilege, the trigger can be altered.
As of version 9i, it is O7_DICTIONARY_ACCESSIBILITY parameter that governs/protects the
access to SYS objects, this means that if a schema trigger is owned by user SYS, even if the
user has the ALTER ANY TRIGGER privilege, the logon would still fail as this privilege
is not sufficient to alter SYS objects unless O7_DICTIONARY_ACCESSIBILITY = true.
For security reasons, Oracle recommends that you use this setting only with great caution.
RELATED DOCUMENTS
----------------- Note:120712.1 Database or Logon Event Trigger becomes Invalid: Who can Connect? Note:220491.1 How to Prevent Users From Log Into a Database Within Defined Periods Note:116636.1 ORA-4098 or ORA-4045 logging on to database having AFTER LOGON
event trigger
第二章 实验中用到的SQL总结
grant ADMINISTER DATABASE TRIGGER to lhr8; GRANT ALTER ANY TRIGGER TO LHR8;
CREATE OR REPLACE TRIGGER CHK_IP_LHR AFTER LOGON ON DATABASE DECLARE V_IPADDR VARCHAR2(30); V_LOGONUSER VARCHAR2(60); BEGIN SELECT SYS_CONTEXT('USERENV', 'IP_ADDRESS'), SYS_CONTEXT('USERENV', 'SESSION_USER') INTO V_IPADDR, V_LOGONUSER FROM DUAL; IF V_IPADDR LIKE ('192.168.59.%') THEN RAISE_APPLICATION_ERROR('-20001', 'User '||V_LOGONUSER||' is not allowed to connect from '||V_IPADDR); END IF; END; /
set pagesize 9999 set line 9999 col NAME format a40 col KSPPDESC format a50 col KSPPSTVL format a20 SELECT a.INDX, a.KSPPINM NAME, a.KSPPDESC, b.KSPPSTVL FROM x$ksppi a, x$ksppcv b WHERE a.INDX = b.INDX and lower(a.KSPPINM) like lower('%?meter%'); alter system set "_system_trig_enabled"=true; alter system reset "_system_trig_enabled" scope=spfile sid='*'; iptables -I INPUT -s 192.168.59.129 -j DROP service iptables save
|
-------------------------------------------------------------------------
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