009.04.91.30. How does the `01_users` script handle user authentication in GRUB2?

01_users SCRIPT -

CODE SEGMENT FOR USER AUTHENTICATION -  
if [ -n "${GRUB2_PASSWORD}" ]
then
    set supersusers="root"
    export superusers
password_pbkdf2 root ${GRUB2_PASSWORD}
fi

Steps for setting up passwords and defining superusers -

CHECK FOR GRUB2_PASSWORD : It checks if variable `GRUB2_PASSWORD` is defined which contains a hashed password loaded from `user.cfg`

DEFINE SUPERUSERS : If the password is set, it defines a `superusers` variable and assigns it the value "root".

EXPORT SUPERUSERS : The 'superusers' variable is exported so that its value is available to other scripts.

PASSWORD SETUP : It sets password for root user using `password_pbkdf2` command with user "root" and hashed password.