Lazy IP ban command for bash v2

# For Debian-based systems
# Add this to your .bashrc
banip() {
  if [ -z $1 ]
    echo "Parameter not passed."
  then
    iptables -A INPUT -s $1 -j DROP
    iptables -A OUTPUT -d $1 -j DROP
    echo "$1 banned."
    #If you get an error, switch the comment out below
    #/etc/init.d/iptables save
    iptables-save
  fi
}
#usage: banip XX.XX.XX.XX
# Blocks incoming and outgoing connections to a given IP or subnet