Cloudflare IPTABLES and IPSET scripts - fixed 2022-02-23

cloudflare-ipset.sh

#!/bin/bash

# name of the ipset - v4 or v6 will be appended.
IPSET_NAME=cloudflare-

# argument: v4 or v6 (defaults to v4)
cloudflare_ipset ()
{
        local ipv
        local inetv

        if [ -z "$1" ]; then ipv="v4"; else ipv="$1"; fi

        if [ "$ipv" = "v4" ]
                then inetv="inet"
                else inetv="inet6"
        fi

        IPSET_NAME="$IPSET_NAME$ipv"

        local content_re='^[0-9a-f:.\r\n/ ]+$'

        local url="https://www.cloudflare.com/ips-$ipv/"
        local ipdata; # local is a command that affects $?, so must be separate!
        ipdata=$(curl --fail -L "$url" 2>/dev/null | tr -s "[:space:]" " ")
        local ret=$?

        if [ $ret -eq 0 ] && [[ $ipdata =~ $content_re ]]; then
                if ipset list $IPSET_NAME 2>/dev/null 1>/dev/null
                then
                        echo "Updating $IPSET_NAME set..."
                        ipset flush $IPSET_NAME
                else
                        echo "Creating $IPSET_NAME set..."
                        ipset create $IPSET_NAME hash:net family $inetv
                fi
                for i in $ipdata
                do
                        ipset add $IPSET_NAME $i
                done

                local count=`ipset list $IPSET_NAME | wc -l`
                count=$((count-7))
                echo "Set $IPSET_NAME now has $count entries."
                return 0
        else
                echo "Download failed, sets not modified."
                return 1
        fi
}

cloudflare_ipset "$1"

exit $?

cloudflare-iptables.sh

#!/bin/bash

# name of the custom chain:
CHAIN_NAME=cloudflare
# target for the last (default) rule in the chain:
# (use REJECT, DROP or a custom chain name, ACCEPT would not make sense)
CHAIN_POLICY=DROP

# argument: v4 or v6 (defaults to v4)
cloudflare_iptables ()
{
        local ipv

        if [ -z "$1" ]; then ipv="v4"; else ipv="$1"; fi

        local iptcmd
        if [ "$ipv" = "v4" ]
                then iptcmd="iptables"
                else iptcmd="ip6tables"
        fi

        local content_re='^[0-9a-f:.\r\n/ ]+$'

        local url="https://www.cloudflare.com/ips-$ipv/"
        local ipdata; # local is a command that affects $?, so must be separate!
        ipdata=$(curl --fail -L "$url" 2>/dev/null | tr -s "[:space:]" " ")
        local ret=$?

        if [ $ret -eq 0 ] && [[ $ipdata =~ $content_re ]]; then
                if $iptcmd --list-rules $CHAIN_NAME 2>/dev/null 1>/dev/null
                then
                        echo "Updating $CHAIN_NAME chain..."
                        $iptcmd --flush $CHAIN_NAME
                else
                        echo "Creating $CHAIN_NAME chain..."
                        $iptcmd --new-chain $CHAIN_NAME
                fi
                for i in $ipdata
                do
                        $iptcmd -A $CHAIN_NAME -s $i -j ACCEPT
                done
                $iptcmd -A $CHAIN_NAME -j $CHAIN_POLICY

                local count=`$iptcmd --list-rules $CHAIN_NAME | wc -l`
                count=$((count-1))
                echo "Chain $CHAIN_NAME now has $count rules."
                return 0
        else
                echo "Download failed, chains not modified."
                return 1
        fi
}

cloudflare_iptables "$1"

exit $?

Thank you for the hint, should be all better now!

Wonderful - thank you for the script. :)