在日常业务运维中，有时为了配合解决问题，需要给非运维人员开通系统账号，用于查询日志或代码。通常为了系统安全或避免不必要的误操作等目的，会将账号权限降至最低。下面介绍下在Linux下通过受限bash创建指定权限账号的操作记录：
[root@mq-server ~]# ln -s /bin/bash /bin/rbash[root@mq-server ~]# useradd -s /bin/rbash wangshibo[root@mq-server ~]# passwd wangshibo[root@mq-server ~]# mkdir /home/wangshibo/bin[root@mq-server ~]# chown root. /home/wangshibo/.bash_profile [root@mq-server ~]# chmod 755 /home/wangshibo/.bash_profile[root@mq-server ~]# vim /home/wangshibo/.bash_profile //复制下面的内容覆盖原内容# .bash_profile # Get the aliases and functionsif [ -f ~/.bashrc ]; then . ~/.bashrcfi # User specific environment and startup programs PATH=$HOME/bin export PATH [root@mq-server ~]# ln -s /bin/cat /home/wangshibo/bin/cat[root@mq-server ~]# ll /home/wangshibo/total 4drwxr-xr-x 2 root root 4096 Nov 25 23:38 bin[root@mq-server ~]# ll /home/wangshibo/bin/total 0lrwxrwxrwx 1 root root 8 Nov 25 23:12 cat -> /bin/cat
如上设置后，可以发现创建的wangshibo用户家目录下的文件权限是root.root，上面只设置了wangshibo用户的cat权限，并且只能cat查看wangshibo用户家目录/home/wangshibo下的文件。除了cat命令外。不能执行其他命令！
[wangshibo@mq-server ~]$ cat /var/log/messagescat: /var/log/messages: Permission denied[wangshibo@mq-server ~]$ ls-rbash: /home/wangshibo/bin/ls: No such file or directory[wangshibo@mq-server ~]$ touch test-rbash: /home/wangshibo/bin/touch: No such file or directory
如果要想在其家目录下有其他命令的执行权，那么需要添加这些命令的软链接到/home/wangshibo/bin目录下（可以通过which命令查看二进制命令的全路径）
[root@mq-server ~]# ln -s /bin/ls /home/wangshibo/bin[root@mq-server ~]# ln -s /bin/touch /home/wangshibo/bin[root@mq-server ~]# ln -s /bin/mkdir /home/wangshibo/bin[root@mq-server ~]# ln -s /usr/bin/vim /home/wangshibo/bin/[root@mq-server ~]# ll /home/wangshibo/bin/total 0lrwxrwxrwx 1 root root 8 Nov 25 23:12 cat -> /bin/catlrwxrwxrwx 1 root root 7 Nov 25 23:44 ls -> /bin/lslrwxrwxrwx 1 root root 10 Nov 25 23:45 mkdir -> /bin/mkdirlrwxrwxrwx 1 root root 10 Nov 25 23:44 touch -> /bin/touchlrwxrwxrwx 1 root root 12 Nov 25 23:45 vim -> /usr/bin/vim
这样，wangshibo用户就拥有了上面加入的命令的执行权
[root@mq-server ~]# su - wangshibo[wangshibo@mq-server ~]$ lsbin[wangshibo@mq-server ~]$ touch test[wangshibo@mq-server ~]$ mkdir ops[wangshibo@mq-server ~]$ vim test[wangshibo@mq-server ~]$ cat testdsfdsafsadf[wangshibo@mq-server ~]$ rm -f test-rbash: rm: command not found[wangshibo@mq-server ~]$ ls /usr/bin etc games include lib lib64 libexec local sbin share src tmp[wangshibo@mq-server ~]$ cat /var/log/messagescat: /var/log/messages: Permission denied