Creates a new user and configures for SSH tunnel only DB access

create_ssh_tunnel_user.sh

#!/bin/bash
################################################################################
# Creates a new user and configures for SSH tunnel only DB access.
#
# Usage:  create_ssh_tunnel_user.sh <username_to_create>
#
################################################################################
set -e  # on error, exit early

if [[ -z $1 ]]
then
  echo "No username supplied! Exiting ..."
  exit 1
fi

new_user=$1
echo "- creating new user: ${new_user} ..."
adduser "${new_user}"

echo "- adding '${new_user}' to group: db-ssh-tunnel-only ..."
adduser "${new_user}" db-ssh-tunnel-only

ssh_dir=/home/${new_user}/.ssh
echo "- creating and configuring .ssh dir: ${ssh_dir} ..."
mkdir --mode=700 --verbose "${ssh_dir}"
chown ${new_user}:${new_user} "${ssh_dir}"

authorized_keys_file=$ssh_dir/authorized_keys
echo -e "- creating and configuring authorized_keys file: ${authorized_keys_file} ..."
touch "${authorized_keys_file}"
chown ${new_user}:${new_user} "${authorized_keys_file}"
chmod 600 "${authorized_keys_file}"

echo "- verifying..."
echo -n "         User: " && getent passwd "${new_user}"
echo -n "       Groups: " && groups "${new_user}"
echo -n "     .ssh dir: " && ls -l --directory "${ssh_dir}"
echo -n "    keys file: " && ls -l "${authorized_keys_file}"

echo "- finished creating new user: ${new_user}."
exit 0