授权公钥登录，sudo权限脚本

#!/bin/bash
##############################################################
# File Name: key_auth.sh
# Version: V1.0
# Author: Li Shi Chao
# Created Time : 2018-06-08 13:47:42
# 博客园地址:www.cnblogs.com/root0/p/
##############################################################
user=lishichao
dir=/home/$user/.ssh
file=/home/$user/.ssh/authorized_keys
KEY=‘添加自己的公钥‘

check_user(){
if [ $USER == root ];then
  echo "              "
else
  echo "use root execute" && exit 2
fi
}

add_user(){
check=`grep -c "lishichao"  /etc/passwd`
if [ $check -eq 0 ];then
 useradd $user && id  $user &>1
 if [ $? -eq 0 ];then
  echo "$user 创建成功！！！"
 else
  echo "$user 创建失败！！！"
 fi
else
 echo "用户 $user 已经存在，开始授权认证。"
fi
}

sudo_auth(){
mkdir $dir -p && chmod 700 $dir
chmod 600 $file && chown -R $user.$user $dir
check_key=`grep -c "$KEY" $file`
if [ $check_key -eq 0 ];then
  echo  "$KEY" >> $file
  echo "添加公钥成功"
else
  echo "用户公钥已经存在"
fi

check_sudo=`grep -c "$user" /etc/sudoers`
if [ $check_sudo -eq 0 ];then
  echo "$user        ALL=(ALL)  NOPASSWD:      ALL" >>/etc/sudoers
else
  echo "sudo权限已经存在"
fi
}

mail(){
check_user
add_user
sudo_auth
}
mail

原文地址：https://www.cnblogs.com/root0/p/9155653.html