MySQL用户和权限及破解root口令（mysql破解方法）

MySQL用户和权限

在MySQL中有一个系统自身就带有的数据库叫MySQL，数据库装好以后系统自带了好几个数据库MySQL就是其中过一个，MySQL数据库有个用户账户权限相关的表叫user表，在其中就有创建的用户。

MySQL中完整的用户名是由用户+主机名形成，主机名决定了这个用户在哪个主机上能登陆。

一、用户的创建和密码修改

1.用户的创建

createuser'USERNAME'@'HOST'identifiedby'PASSWORD';

USERNAME:用户名

HOST:主机地址

PASSWORD:密码

示例：

MariaDB[(none)]>createusermasuri@192.168.73.133identifiedby'centos';

QueryOK,0rowsaffected(0.01sec)

MariaDB[(none)]>selectuser,host,passwordfrommysql.user;

+--------+-----------------------+-------------------------------------------+

|user|host|password|

+--------+-----------------------+-------------------------------------------+

|root|localhost||

|root|localhost.localdomain||

|root|127.0.0.1||

|root|::1||

||localhost||

||localhost.localdomain||

|masuri|192.168.73.133|*128977E278358FF80A246B5046F51043A2B1FCED|

+--------+-----------------------+-------------------------------------------+

7rowsinset(0.00sec)

MySQL中有匿名账户，可以通过跑安全加固脚本mysql_secure_installation来进行删除，也可以手动将其删除。

删除用户：

DROPUSER'USERNAME'@'HOST';

示例：

MariaDB[(none)]>selectuser,host,passwordfrommysql.user;

+--------+-----------------------+-------------------------------------------+

|user|host|password|

+--------+-----------------------+-------------------------------------------+

|root|localhost||

|root|localhost.localdomain||

|root|127.0.0.1||

|root|::1||

||localhost||

||localhost.localdomain||

|masuri|192.168.73.133|*128977E278358FF80A246B5046F51043A2B1FCED|

+--------+-----------------------+-------------------------------------------+

7rowsinset(0.00sec)

MariaDB[(none)]>DROPUSER''@'localhost';

QueryOK,0rowsaffected(0.00sec)

MariaDB[(none)]>DROPUSER''@'localhost.localdomain';

QueryOK,0rowsaffected(0.00sec)

MariaDB[(none)]>selectuser,host,passwordfrommysql.user;

+--------+-----------------------+-------------------------------------------+

|user|host|password|

+--------+-----------------------+-------------------------------------------+

|root|localhost||

|root|localhost.localdomain||

|root|127.0.0.1||

|root|::1||

|masuri|192.168.73.133|*128977E278358FF80A246B5046F51043A2B1FCED|

+--------+-----------------------+-------------------------------------------+

5rowsinset(0.00sec)

2.密码的修改

mysql密码的修改

SETPASSWORDFORuser=PASSWORD('cleartextpassword')

UPDATEtableSETpassword=password('cleartextpassword')

示例：

对masuri用户做密码的修改

MariaDB[(none)]>SETPASSWORDFORmasuri@192.168.73.133=PASSWORD('magedu');

QueryOK,0rowsaffected(0.00sec)

MariaDB[(none)]>selectuser,host,passwordfrommysql.user;

+--------+-----------------------+-------------------------------------------+

|user|host|password|

+--------+-----------------------+-------------------------------------------+

|root|localhost||

|root|localhost.localdomain||

|root|127.0.0.1||

|root|::1||

|masuri|192.168.73.133|*6B8CCC83799A26CD19D7AD9AEEADBCD30D8A8664|

+--------+-----------------------+-------------------------------------------+#此时密码已经发生改变

root账号口令为空，为root口令设置口令，由于一条一条的设置太过麻烦也可以使用修改表的操作来修改密码

MariaDB[(none)]>updatemysql.usersetpassword=password('centos')whereuser='root';

QueryOK,4rowsaffected(0.01sec)

Rowsmatched:4Changed:4Warnings:0

MariaDB[(none)]>selectuser,host,passwordfrommysql.user;

+--------+-----------------------+-------------------------------------------+

|user|host|password|

+--------+-----------------------+-------------------------------------------+

|root|localhost|*128977E278358FF80A246B5046F51043A2B1FCED|

|root|localhost.localdomain|*128977E278358FF80A246B5046F51043A2B1FCED|

|root|127.0.0.1|*128977E278358FF80A246B5046F51043A2B1FCED|

|root|::1|*128977E278358FF80A246B5046F51043A2B1FCED|

|masuri|192.168.73.133|*6B8CCC83799A26CD19D7AD9AEEADBCD30D8A8664|

+--------+-----------------------+-------------------------------------------+

5rowsinset(0.00sec)

此时密码已经修改但依旧无法登陆，需要将权限刷新

MariaDB[(none)]>FLUSHPRIVILEGES;

QueryOK,0rowsaffected(0.00sec)

二、MySQL权限管理

权限管理涉及到多种权限的类别，比如说有管理类、程序类、数据库级别、表级别和字段级别

管理类：能否创建用户，能否显示数据库列表，能否重新加载配置文件，能否关闭数据库，和复制相关的能否执行，能否管理进程，能否创建临时表，能否创建数据库中的文件。

程序类主要涉及3个程序，函数，存储过程和触发器，例如能否创建，修改，删除和执行这些程序

库，表和字段级别的权限：比如能否在库，表字段里进行增、删、查、改等操作

1.厦门linux培训授权GRANT

授权用户时如果用户不存在可以将其创建出来，在授权前首先要确认自己是管理员有授权的权限。

GRANT

priv_type[(column_list)]

[,priv_type[(column_list)]]...

ON[object_type]priv_level

TOuser_specification[,user_specification]...

[REQUIRE{NONE|ssl_option[[AND]ssl_option]...}]

[WITHwith_option...]

示例：

创建一个wordpress的用户，并授权。

MariaDB[(none)]>CREATEDATABASEwordpress;

QueryOK,1rowaffected(0.02sec)

MariaDB[(none)]>GRANTALLONwordpress.*TOwpuser@'192.168.73.%'identifiedby'mylinuxops';

QueryOK,0rowsaffected(0.00sec)

2.查看用户的权限

MariaDB[(none)]>showgrantsforwpuser@'192.168.73.%';

+------------------------------------------------------------------------------------------------------------------+

|Grantsforwpuser@192.168.73.%|

+------------------------------------------------------------------------------------------------------------------+

|GRANTUSAGEON*.*TO'wpuser'@'192.168.73.%'IDENTIFIEDBYPASSWORD'*EC0DBFB480593BB6ED2EC028A4231A72D8137406'|

|GRANTALLPRIVILEGESON`wordpress`.*TO'wpuser'@'192.168.73.%'|

+------------------------------------------------------------------------------------------------------------------+

2rowsinset(0.00sec)

3.授权的其他选项

MAX_QUESRIES_PER_HOURcount#每小时最多查多少次MAX_UPDATES_PER_HOURcount#每小时最多改多少次MAX_CONNECTIONS_PER_HOUR

count#每小时最多连多少次MAX_USER_CONNECTIONScount#用户的最大数连接数

取消权限

REVOKE

priv_type[(column_list)]

[,priv_type[(column_list)]]...

ON[object_type]priv_level

FROMuser[,user]...

示例：

MariaDB[(none)]>revokedeleteonwordpress.*fromwpuser@'192.168.73.%';

QueryOK,0rowsaffected(0.00sec)

MariaDB[(none)]>showgrantsforwpuser@'192.168.73.%';

+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+

|Grantsforwpuser@192.168.73.%|

+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+

|GRANTUSAGEON*.*TO'wpuser'@'192.168.73.%'IDENTIFIEDBYPASSWORD'*EC0DBFB480593BB6ED2EC028A4231A72D8137406'|

|GRANTSELECT,INSERT,UPDATE,CREATE,DROP,REFERENCES,INDEX,ALTER,CREATETEMPORARYTABLES,LOCKTABLES,EXECUTE,

CREATEVIEW,SHOWVIEW,CREATEROUTINE,ALTERROUTINE,EVENT,TRIGGERON`wordpress`.*TO'wpuser'@'192.168.73.%'|

+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+

2rowsinset(0.00sec)#此时wpuser@'192.168.73.%'已经没有了delete权限

MySQL的root口令破解

工作中有时候可能会遇到root口令丢失的情况，此时可以通过以下方法进行找回root口令

以下为示范如何破解root口令

一、密码未知无法登陆MySQL

[root@localhost~]#mysqlERROR1045(28000):Accessdeniedforuser'root'@'localhost'(usingpassword:NO)

二、破解

1.修改配置文件/etc/my.cnf，添加两行参数

skip_grant_tables:跳过授权表信息，此项生效后再次使用MySQL就无需使用密码了，但是远程的其他用户也可以不使用密码登陆，有一定的风险性

skip_networking:关闭网路功能，由于光启用skip_grant_tables选项，其他用户也可以无需密码登陆MySQL非常危险，所以需要关闭网路功能只允许本地的用户进行操作。

[root@localhost~]#vim/etc/my.cnf[mysqld]

skip_networking=on#不启用网络功能skip_grant_tables=on#跳过授权表[root@localhost~]#servicemysqldrestart

#对位置文件修改后需要重新启动服务Restartingmysqld(viasystemctl):[OK]

2.登陆MySQL，进行密码修改

[root@localhost~]#mysql#此时已经无需输入密码就能登陆WelcometotheMariaDBmonitor.Commandsendwith;or\g.

YourMariaDBconnectionidis11

Serverversion:10.2.23-MariaDB-logSourcedistribution

Copyright(c)2000,2018,Oracle,MariaDBCorporationAbandothers.

Type'help;'or'\h'forhelp.Type'\c'toclearthecurrentinputstatement.

MariaDB[(none)]>UPDATEmysql.userSETpassword=PASSWORD('123456')whereuser='root';#对root的口令进行修改QueryOK,4rowsaffected(0.01sec)

Rowsmatched:4Changed:4Warnings:0

3.口令修改完毕后，需要将配置文件恢复

将刚才启用的两个选项进行注销或者删除，然后重启服务

[root@localhost~]#vim/etc/my.cnf[mysqld]#skip_networking=on#skip_grant_tables=on[root@localhost~]#servicemysqldrestartRestartingmysqld(viasystemctl):[OK]

4.使用新口令登陆MySQL

[root@localhost~]#mysql-uroot-p123456WelcometotheMariaDBmonitor.Commandsendwith;or\g.

YourMariaDBconnectionidis10

Serverversion:10.2.23-MariaDB-logSourcedistribution

Copyright(c)2000,2018,Oracle,MariaDBCorporationAbandothers.

Type'help;'or'\h'forhelp.Type'\c'toclearthecurrentinputstatement.

MariaDB[(none)]>