Setting up GH-pages with custom domain, strict (end-to-end) SSL with CloudFlare DNS & CDN

GH-CF-strict-SSL-w-CDN.md

Custom domains, GH-pages, Cloudflare and strict SSL end-to-end encryption

Why I wrote this

Before Github supported SSL encryption for github pages sites, many people were using CloudFlare (CF) as their DNS provider and CDN proxy. CF allowed users to enable SSL encryption from the CDN end points/proxies to the end user. This was great and it allowed visitors to your website to connect with a secure connection between their browser and the cloudflare CDN box that was serving your content. However, with this setup one (significant) link in the chain remained unencrypted and exposed: The link between your published github pages site and the CF servers. So, in a sense, the warm cozy feeling users were having from seeing https:// and that nice padlock icon in their browser URL bar was disingenuous--Their connection to your original content was not completely encrypted and protected.

Fast forward to today: Github has enabled https for custom domains through provisioning Letsencrypt SSL certificates for Github pages sites. Now you can even pair this functionality with custom domains! In addition, since the CF functionality of providing SSL encrypted connections between their CDN/proxy servers and end users was first introduced, Github has also changed some of the details that one must consider when setting up custom domains. E.g., DNS A records need to point to different IP addresses for reaching GH's GH-pages servers than they used to.

Great, let's try full (strict) end-to-end encryption for GH pages and my personal website! Well, unfortunately, for a long time I could never get the settings page of my personal website (https://izaakbeekman.com) to allow me to check the checkbox to enable https. What's more, every time I googled the issue, the top posts were all about setting up this psuedo https/ssl encryption before GH supported SSL with custom domains, how frustrating! Some hits started to appear on the GH community forms for issues where https/ssl was never being provisioned and the checkbox would remain disabled, however, these issues did not specifically mention CF and the resolution was "contact GH support".

Full end-to-end (strict) encryption with GH pages, custom domains and CF!

Ultimately, I was in touch with GH support for an unrelated GH pages issue, and asked them why I could never get GH to provision a certificate for my GH-pages hosted site, and they gave me the solution. What's more, is that it seems to work!

1. Create your GH-pages repository and setup gh-pages hosting for a user, org, or project level repository following the standard GH instructions.
2. Procure a domain name from a registrar.
3. Set the custom domain name in the GH-pages setting of your repository, this will create a file named CNAME with your registered domain.
4. Only after you have created your repository & registered your domain name should you register your domain with CF and setup DNS records.
5. If you want a top level domain, and a www subdomain, you should use A records with CF to point to GH's servers and then a CNAME record for the www subdomain to point to the top level domain.
6. Ensure that the CF CDN/proxy is OFF for now; this is critical to get GH pages to provision an SSL cert for you.
7. Once you have your custom domain entered in the GH pages settings menu, and you have CF setup to point to GH's servers as per GH's instructions, only then should you point your registrar to CF's nameservers. If these steps are done in a different order, someone can hijack your domain.
8. Now you should be able to navigate to your domain (http) and see your GH pages website. At this point, the use https portion of your GH settings page should have some message about provisioning an SSL certificate, if the https checkbox is still greyed out. If not, you may have to wait for DNS records to propagate more. If it's been a day or longer, you should try removing the custom domain CNAME record in the GH pages setting, then adding it back. Eventually you will be able to click the "enable https" checkbox.
9. Only once you have had an SSL certificate provisioned for your site, and you have checked the "enable https" box in the github pages settings should you back over to CF and enable the CF CDN/Proxy (click the grey cloud icons next to DNS records so that they become orange) and then navigate to the "encryption" tab and enable https/ssl strict (full)

After you follow these steps, your website should be available at the https:// url and have end-to-end SSL encryption from the GH servers hosting your static website, to the CF servers, to the CF CDN/proxy servers, to the user.

If you have questions leave them here or reach out on twitter; I'm @zbeekman there too.

Anyone find a good solution to this?

My solution was just "stop using cloudflare". I was only using it for improved compatibility with legacy clients with outdated CA stores, and eventually that stopped working too. Now I use my own VPS as a reverse-proxy instead.