user_creation_and_ssh_key_configuration

#!/bin/bash

Adding_Users () {
        echo "Enter the User-name : $1"
        if [[ $(sudo cat /etc/passwd | grep "$1") ]];then
                echo "user $1 already exist!"
        else
                sudo useradd $1
                sudo mkdir /home/$1/.ssh
                sudo chown $1:$1 /home/$1/.ssh ; sudo chmod 700 /home/$1/.ssh
                sudo ssh-keygen -t rsa -N "" -f /home/$1/.ssh/id_rsa 2>/dev/null
                sudo chown $1:$1 /home/$1/.ssh/id_rsa ; sudo chown $1:$1 /home/$1/.ssh/id_rsa.pub
                sudo touch /home/$1/.ssh/authorized_keys ; sudo cp /home/$1/.ssh/id_rsa.pub /home/$1/.ssh/authorized_keys ; sudo chmod 600 /home/$1/.ssh/authorized_keys
                sudo chown $1:$1 /home/$1/.ssh/authorized_keys
        fi
}

Adding_Users $1


##This script will create a user and the username is given by user-input ($1).
##If the user is already exist in the working system, the script will display a message like "user already exist".
##"ssh-keygen -t rsa -N "" -f /home/$1/.ssh/id_rsa" this command will ignore the phassphrase and save the key which we mentioned after -f flag.
##"Adding_Users" is a shell function which we use inside this bash script.