Bash script to update CloudFlare IPs in an ipset

cloudflare-ipset.sh

#!/bin/bash

IPSET="/usr/sbin/ipset"
CURL="/usr/bin/curl"
DATE="/bin/date"

for VER in 4 6; do

    URL="https://www.cloudflare.com/ips-v$VER"
    SET_NAME="CloudFlare.IPv$VER"
    TMP_NAME="$SET_NAME.$($DATE +%s)"

    IP_LIST="$($CURL -s $URL)"
    if [ ! $? ]; then
        echo "Unable to download IPv$VER IPs list"
        exit 1
    fi

    $IPSET create $TMP_NAME hash:net family "inet${VER/4/}"
    for IP in $IP_LIST; do
        $IPSET add $TMP_NAME $IP
    done

    if $IPSET list $SET_NAME &>/dev/null; then
        $IPSET swap $SET_NAME $TMP_NAME
        $IPSET destroy $TMP_NAME
    else
        $IPSET rename $TMP_NAME $SET_NAME
    fi

done