get-cloudflare-ips.sh

#!/bin/bash

# add this to crontab for automatic updates:
# @daily root /path/to/get-cloudflare-ips.sh

FILENAMEv4="/etc/network/cloudflare-ips-v4.new"
EXISTINGv4="/etc/network/cloudflare-ips-v4"
FILENAMEv6="/etc/network/cloudflare-ips-v6.new"
EXISTINGv6="/etc/network/cloudflare-ips-v6"

# create files
touch $EXISTINGv6 $EXISTINGv4

NGINXCF="/etc/nginx/conf.d/cloudflare.conf"
curl -L -so $FILENAMEv4 https://www.cloudflare.com/ips-v4
curl -L -so $FILENAMEv6 https://www.cloudflare.com/ips-v6

# check the size since Cloudflare once messed it up
SIZEv4=$(du -sb $FILENAMEv4 | awk '{ print $1 }')
SIZEv6=$(du -sb $FILENAMEv4 | awk '{ print $1 }')
if ((SIZEv4<150)) || ((SIZEv6<150)) ; then
    echo "File is too small, exiting";
    exit 1
else
    diff -q $FILENAMEv4 $EXISTINGv4 >/dev/null
    DIFFv4=$?
    diff -q $FILENAMEv6 $EXISTINGv6 >/dev/null
    DIFFv6=$?
    if [ $DIFFv4 == 1 ] || [ $DIFFv6 == 1 ]
    then
        mv $FILENAMEv4 $EXISTINGv4
        mv $FILENAMEv6 $EXISTINGv6

        # update nginx cloudflare proxy IP mapping
        echo "# updated by /etc/network/get-cloudflare.sh" > $NGINXCF
        for line in $(cat $EXISTINGv4 $EXISTINGv6)
        do
            echo "set_real_ip_from $line;" >> $NGINXCF
        done
        echo "real_ip_header CF-Connecting-IP;" >> $NGINXCF
        nginx -t && service nginx reload
    fi
fi