http://blog.csdn.net/nosodeep/article/details/8549331
http://os.51cto.com/art/201703/534895.htm
http://kuanghy.github.io/2017/02/20/rbash
https://wenku.baidu.com/view/90a161e8e009581b6bd9ebed.html
[root@bao-work-4 ~]# ln -s /bin/bash /bin/rbash
[root@bao-work-4 ~]# useradd -s /bin/rbash bigbao
[root@bao-work-4 ~]# chown -R root:bigbao /home/bigbao/.bashrc /home/bigbao/.bash_profile
[root@bao-work-4 ~]# chmod 640 /home/bigbao/.bashrc /home/bigbao/.bash_profile
[root@bao-work-4 ~]# mkdir /home/bigbao/bin
[root@bao-work-4 ~]# echo "export PATH=/home/bigbao/bin" >> /home/bigbao/.bash_profile
[root@bao-work-4 ~]# ln -s /usr/bin/ssh /home/bigbao/bin/ssh
[root@bao-work-4 ~]# passwd bigbao