mysql审计功能一直都是弱项:
1.之前有人借助于init-connect和binlog实现变相审计,不过比较悲剧的是不能对root用户(超级权限的用户)进行审计！可以参考：http://bbs.chinaunix.net/forum.php?mod=viewthread&tid=3632588
2.Oracle公司在5.5的企业版也增加了mysql-audit plugin,问题是该插件类似于general-log,而且仅仅存在于企业版！可以参考：http://www.cnblogs.com/cenalulu/archive/2012/11/12/mysql_audit_plugin_test.html
3.macfee公司基于percona开发的mysql audit 插件。
macfee的mysql audit插件虽然日志信息比较大，对性能影响大，但是如果想要开启审计，那也应该忍受了。介绍几个参考地址：
wiki首页：https://github.com/mcafee/mysql-audit/wiki
二进制包下载：https://bintray.com/mcafee/mysql-audit-plugin/release包含了5.1,5.5,5.6对应的二进制包
使用非常简单！可以在线开启，也可以使用plugin-load= AUDIT = libaudit_plugin.so重新启动！
在线开启非常简单！
//1. 下载对应版本的二进制包 //2. 查看mysql插件目录 mysql> SHOW GLOBAL VARIABLES LIKE 'plugin_dir'; +---------------+--------------------------------+ | Variable_name | Value | +---------------+--------------------------------+ | plugin_dir | /usr/lib64/mysql/plugin/ | +---------------+--------------------------------+ 1 row in set (0.01 sec) //3. 复制下载的so文件至plugin_dir //4. 安装插件 mysql> INSTALL PLUGIN AUDIT SONAME 'libaudit_plugin.so'; //5. 查看对应版本 mysql> SHOW GLOBAL STATUS LIKE 'AUDIT_version'; +---------------+-----------+ | Variable_name | Value | +---------------+-----------+ | Audit_version | 1.0.8-527 | +---------------+-----------+ 1 row in set (0.00 sec) //安装成功 //6.开启audit功能 mysql> SET GLOBAL audit_json_file=ON; //7.执行任何语句(默认会记录任何语句)，然后去mysql数据目录查看mysql-audit.json文件(默认为该文件)
当然，我们还可以通过命令查看audit相关的命令
+---------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | Variable_name | Value | +---------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | audit_checksum | | | audit_delay_cmds | | | audit_delay_ms | 0 | | audit_force_record_logins | OFF | | audit_header_msg | ON | | audit_json_file | ON | | audit_json_file_bufsize | 1 | | audit_json_file_flush | OFF | | audit_json_file_retry | 60 | | audit_json_file_sync | 0 | | audit_json_log_file | mysql-audit.json | | audit_json_socket | OFF | | audit_json_socket_name | /tmp/mysql.audit__data_mysql_3111 | | audit_json_socket_retry | 10 | | audit_offsets | | | audit_offsets_by_version | ON | | audit_password_masking_cmds | CREATE_USER,GRANT,SET_OPTION,SLAVE_START,CREATE_SERVER,ALTER_SERVER,CHANGE_MASTER | | audit_password_masking_regex | identified(?:/\*.*?\*/|\s)*?by(?:/\*.*?\*/|\s)*?(?:password)?(?:/\*.*?\*/|\s)*?['|"](?<psw>.*?)(?<!\\)['|"]|password(?:/\*.*?\*/|\s)*?\((?:/\*.*?\*/|\s)*?['|"](?<psw>.*?)(?<!\\)['|"](?:/\*.*?\*/|\s)*?\)|password(?:/\*.*?\*/|\s)*?(?:for(?:/\*.*?\*/|\s)*?\S+?)?(?:/\*.*?\*/|\s)*?=(?:/\*.*?\*/|\s)*?['|"](?<psw>.*?)(?<!\\)['|"]|password(?:/\*.*?\*/|\s)*?['|"](?<psw>.*?)(?<!\\)['|"] | | audit_record_cmds | drop,alert,select,update,delete,insert | | audit_record_objs | | | audit_uninstall_plugin | OFF | | audit_validate_checksum | ON | | audit_validate_offsets_extended | ON | | audit_whitelist_cmds | | | audit_whitelist_users | | +---------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
其中我们需要关注的参数有：
1. audit_json_file //是否开启audit功能 2. audit_json_log_file //记录文件的路径和名称信息 3. audit_record_cmds //audit记录的命令,默认为记录所有命令 //可以设置为任意dml、dcl、ddl的组合 //如：audit_record_cmds="select,insert,delete,update" //还可以在线设置set global audit_record_cmds=NULL //(表示记录所有命令) 4. audit_record_objs //audit记录操作的对象,默认为记录所有对象, //可以用SET GLOBAL audit_record_objs=NULL设置为默认 //也可以指定为下面的格式 //audit_record_objs=",test.*,mysql.*,information_schema.*" 5. audit_whitelist_users //用户白名单
另外还有offsets参数的设置,如果开启audit_offsets_by_version=ON，则必须设置audit_offsets = 6136, 6184, 3816, 4312, 88, 2592, 96, 0, 32, 104(数字为工具计算出来的结果,各种版本不一样)。如果设置不当，在mysql错误日志中将会有如下错误内容
[Note] Audit Plugin: setup_offsets audit_offsets: (null) validate_checksum: 1 offsets_by_version: 1 [ERROR] Couldn't load plugin named 'AUDIT ' with soname ' libaudit_plugin.so'.
可以通过计算offsets,并分配适当值
1、Download the offset-extract.sh script from: https://raw.github.com/mcafee/mysql-audit/master/offset-extract/offset-extract.sh
2、确认gdb是否已安装(ensure gdb is installed)
3、chmod +x offset-extract.sh
4、./offset-extract.sh /data/app/mysql/mysql/bin/mysqld (mysqld路径)
//offsets for: /data/app/mysql/mysql/bin/mysqld (5.5.29)
{"5.5.29","53eea146441ed02575184b11f95283a1", 6032, 6080, 3784, 4208, 88, 2568},
5、修改my.cnf 在[mysqld]增加如下
plugin-load=AUDIT=libaudit_plugin.so
audit_offsets=6032, 6080, 3784, 4208, 88, 2568
offsets具体可以参考 https://github.com/mcafee/mysql-audit/wiki/Troubleshooting
附属一份切割mysql-audit.json的脚本，比较low
#!/bin/bash
PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
export PATH
file="mysql-audit.json"
newfile="${file}_`date '+%Y%m%d%H%M%S'`"
max=50000
cd /data/mysql/
num=`cat ${file}|wc -l`
if [ ${num} -gt ${max} ]; then
split -l ${max} ${file} ${newfile}
chown mysql:mysql ${newfile}ab
chmod 660 ${newfile}ab
mysql -uroot -pxxx -Pxxx -e"SET GLOBAL audit_json_file=OFF;"
mv ${newfile}ab ${file}
mysql -uroot -pxxx -Pxxx -e"SET GLOBAL audit_json_file=ON;"
else
echo ${num}
fi
最后建议使用percona官方内置的audit，macfee的audit据说会引起crash。目前还在观测中...
来源：http://imysqldba.blog.51cto.com
