CloudFlare or other WAF forwarding IPs

Good Afternoon,

We’re testing adding CloudFlare to the front of our sites for CDN and Edge-caching.

We ran into an issue where after we whitelist all the CloudFlare IPs in WP-Cerber, we’re getting a lot of login attempts because the IPs are all whitelisted.

Cloudflare passes this header through: “CF-Connecting-IP”, which the value is the actual IP of the user.

Is there anyway you can add a “CloudFlare” option to use that CF-Connecting-IP for filtering / blocking? I know this is kind of specific as a feature. So maybe a text box with optional headers to add custom headers to check, right under the “My site is behind a reverse proxy”.