ssh_dir_permissions() {
    sudo chown -R $USER:$USER $HOME/.ssh
    sudo chmod 00700 $HOME/.ssh
    sudo chmod 600 $HOME/.ssh/authorized_keys
    sudo chmod 400 $HOME/.ssh/id_rsa
    sudo chmod 644 $HOME/.ssh/id_rsa.pub
    sudo chmod 600 $HOME/.ssh/known_hosts
}