Whitelist Cloudflare IPs

Bash script for whitelisting cloudflare ips as well as setting nginx config to show real ips. Also opens port 2408 to cloudflare for railgun setup. To disable the railgun setup remove the line that opens port 2408. Otherwise create a new bash script touch cloudflarewhitelister.sh , copy and paste the contents into the file. Set the file to be executable chmod +x cloudflarewhitelister.sh And just set it to run a couple times a day.

#!/bin/bash
echo "#Cloudflare" > /etc/nginx/conf.d/00_real_ip_cloudflare_00.conf;
        iptables -F cloudflare;
        iptables -N cloudflare;
for i in 'curl https://www.cloudflare.com/ips-v4'; do
        iptables -A cloudflare -p tcp --sport 2408 -s $i -j ACCEPT;
        iptables -A cloudflare -p tcp -m multiport --dports http,https -s $i -j ACCEPT;
        echo "set_real_ip_from $i;" >> /etc/nginx/conf.d/00_real_ip_cloudflare_00.conf;
done

iptables-save > /etc/sysconfig/iptables
echo "real_ip_header CF-Connecting-IP;" >> /etc/nginx/conf.d/00_real_ip_cloudflare_00.conf;

Nginx Real IP

Since CloudFlare acts as a reverse proxy, all connections now come from one of CloudFlare's IP addresses. CloudFlare follows industry standards and includes the originating IP address in the X-Forwarded-For header. The CF-Connecting-IP header may also be used. To preserve the originating IP of your visitor, use the following Nginx module and parameters:

http://nginx.org/en/docs/http/ngx_http_realip_module.html

   # Cloudflare
   set_real_ip_from   199.27.128.0/21;
   set_real_ip_from   173.245.48.0/20;
   set_real_ip_from   103.21.244.0/22;
   set_real_ip_from   103.22.200.0/22;
   set_real_ip_from   103.31.4.0/22;
   set_real_ip_from   141.101.64.0/18;
   set_real_ip_from   108.162.192.0/18;
   set_real_ip_from   190.93.240.0/20;
   set_real_ip_from   188.114.96.0/20;   
   set_real_ip_from   197.234.240.0/22;
   set_real_ip_from   198.41.128.0/17;
   set_real_ip_from   162.158.0.0/15;
   set_real_ip_from   104.16.0.0/12;
   set_real_ip_from   2400:cb00::/32;
   set_real_ip_from   2606:4700::/32;
   set_real_ip_from   2803:f800::/32;
   set_real_ip_from   2405:b500::/32;
   set_real_ip_from   2405:8100::/32;
   real_ip_header     CF-Connecting-IP;