#!/bin/sh

[ -n "$1" ] && login=$1 || read -p "provide login: " login
[ -n "$2" ] && ssh_key=$2 || read -p "provide ssh key: " ssh_key

ssh_dir=/home/$login/.ssh
mkdir -p "$ssh_dir"
[ ! -f "$ssh_dir/authorized_keys" ] && touch $ssh_dir/authorized_keys

# add it to authorized_keys but avoid adding it twice
ak=$ssh_dir/authorized_keys
[ ! grep "$ssh_key" $ak ] && echo "$ssh_key" >> $ak

# ssh wont work without it
chmod -R 0700 /home/$login/.ssh
chown -R $login:$login $ssh_dir