Maybe this is more of a home lab question, but I’m utterly clueless regarding PKI and HTTPS certs, despite taking more than one class that goes into some detail about how the system works. I’ve tried finding guides on how to set up your own CA, but my eyes glaze over after the third or fourth certificate you have to generate.
Anyway, I know you need a public DNS record for HTTPS to work, and it struck me recently that I do in fact own a domain name that I currently use as my DNS suffix on my LAN. Is there a way I can get Let’s Encrypt to dole out a wildcard certificate I can use on the hosts in my LAN so I don’t have to fiddle with every machine that uses every service I’m hosting? If so, is there a guide for the brain dead one could point me to? Maybe doing this will help me grock the whole PKI thing.
UPDATE:
Here’s what I ended up doing:
- set up cloudflare as the DNS provider for my domain
- use certbot plus the cloudflare DNS plugin to create a wildcard cert. Because I want to use wildcard certs and because the web servers are on a NATed private LAN, HTTP-01 challenge cannot be used. Wildcard certs use a DNS challenge. From what I understand of the certbot docs, the HTTP challenge makes a certain HTTP resource available on the web server, then requests that resource, presumably via an external client, to verify that you own the domain. the DNS challenge works by temporarily placing a TXT record in your DNS server. This method requires your DNS provider to have an accessible API that allows the modification of resource records.
- Once the cert and key are generated, I place them on the servers I want to to make use of them and set up the web server accordingly.
- Visit the websites and confirm that HTTPS works.
There are some other hiccups that I’m guessing aren’t related to HTTPS. Per My earlier question about self hosting, I’m experimenting with NodeBB. I cannot get the two test instances to federate, which I initially assumed was an issue with HTTPS. That’s a question best asked elsewhere, though I thought it relevant to note because it was my initial purpose for setting up HTTPS.
I use Caddy for this. I’ll leave links to the documentation as well as a few examples.
Here’s the documentation for wildcard certs. https://caddyserver.com/docs/automatic-https#wildcard-certificates
Here’s how you add DNS providers to Caddy without Docker. https://caddy.community/t/how-to-use-dns-provider-modules-in-caddy-2/8148
Here’s how you do it with Docker. https://github.com/docker-library/docs/tree/master/caddy#adding-custom-caddy-modules
Look for the DNS provider in this repository first. https://github.com/caddy-dns
Here’s documentation about using environment variables. https://caddyserver.com/docs/caddyfile/concepts#environment-variables
Docker
A few examples of Dockerfiles. These will build Caddy with DNS support.
DuckDNS
FROM caddy:2-builder AS builder RUN xcaddy build --with github.com/caddy-dns/duckdns FROM caddy:2 COPY --from=builder /usr/bin/caddy /usr/bin/caddy
Cloudflare
FROM caddy:2-builder AS builder RUN xcaddy build --with github.com/caddy-dns/cloudflare FROM caddy:2 COPY --from=builder /usr/bin/caddy /usr/bin/caddy
Porkbun
FROM caddy:2-builder AS builder RUN xcaddy build --with github.com/caddy-dns/porkbun FROM caddy:2 COPY --from=builder /usr/bin/caddy /usr/bin/caddy
Configure DNS provider
This is what to add the the Caddyfile, I’ve used these in the examples that follow this section. You can look at the repository for the DNS provider to see how to configure it for example.
DuckDNS
https://github.com/caddy-dns/cloudflare?tab=readme-ov-file#caddyfile-examples
tls { dns duckdns {env.DUCKDNS_API_TOKEN} }
CloudFlare
https://github.com/caddy-dns/cloudflare?tab=readme-ov-file#caddyfile-examples Dual-key
tls { dns cloudflare { zone_token {env.CF_ZONE_TOKEN} api_token {env.CF_API_TOKEN} } }
Single-key
tls { dns cloudflare {env.CF_API_TOKEN} }
PorkBun
https://github.com/caddy-dns/porkbun?tab=readme-ov-file#config-examples Global
{ acme_dns porkbun { api_key {env.PORKBUN_API_KEY} api_secret_key {env.PORKBUN_API_SECRET_KEY} } }
or per site
tls { dns porkbun { api_key {env.PORKBUN_API_KEY} api_secret_key {env.PORKBUN_API_SECRET_KEY} } }
Caddyfile
And finally the Caddyfile examples.
DuckDNS
Here’s how you do it with DuckDNS.
*.example.org { tls { dns duckdns {$DUCKDNS_TOKEN} } @hass host home-assistant.example.org handle @hass { reverse_proxy home-assistant:8123 } }
Also you can use environment variables like this.
*.{$DOMAIN} { tls { dns duckdns {$DUCKDNS_TOKEN} } @hass host home-assistant.{$DOMAIN} handle @hass { reverse_proxy home-assistant:8123 } }
CloudFlare
*.{$DOMAIN} { tls { dns cloudflare {env.CF_API_TOKEN} } @hass host home-assistant.{$DOMAIN} handle @hass { reverse_proxy home-assistant:8123 } }
Porkbun
*.{$DOMAIN} { tls { dns porkbun { api_key {env.PORKBUN_API_KEY} api_secret_key {env.PORKBUN_API_SECRET_KEY} } } @hass host home-assistant.{$DOMAIN} handle @hass { reverse_proxy home-assistant:8123 } }
I did basically this w/ Cloudflare, and it worked perfectly. I used to do ACME requests, but this is simpler and doesn’t require me to route traffic into my LAN. I now expose a handful of services, but I used to have to expose all services for TLS cert renewal to work.
thank you for providing such a thorough reply, good shit
Thanks for being so detailed!
I use caddy for straightforward https, but every time I try to use it for a service that isn’t just a reverse_proxy entry, I really struggle to find resources I understand… and most of the time the “solutions” I find are outdated and don’t seem to work. The most recent example of this for me would be Baikal.
Do you have any recommendations for where I might get good examples and learn more about how do troubleshoot and improve my Caddyfile entries?
Thanks!
Ah, PHP, there’s your problem. 😀
Honestly, I just proxy to a separate nginx server to handle the PHP bits, it’s not worth cluttering up my nice, clean Caddy setup with that nonsense.
Unfortunately that’s one area I am bad with, I tend to use reverse_proxy for most such as Baikal running with the ckulka/baikal Docker image (which runs Nginx or Apache), otherwise I only static sites.
I’d start by looking at Baikal’s config for Apache and Nginx, https://sabre.io/baikal/install/ and comparing to the directives for Caddy, https://caddyserver.com/docs/caddyfile/directives and
Since it uses PHP, it will need that, https://caddyserver.com/docs/caddyfile/patterns#php
Upon my searches I came across this, it talks about running Baikal with Caddy specifically. https://github.com/caddyserver/caddy/issues/497
I hope that this provided some helpful directions.
I do the same!
I have a provider that is not supported by caddy, but I can still use it via duckdns delegation!
https://github.com/caddy-dns/duckdns?tab=readme-ov-file#challenge-delegation
Challenge delegation
To obtain a certificate using ACME DNS challenges, you’d use this module as described above. But, if you have a different domain (say,
my.example.com
) CNAME’d to your Duck DNS domain, you have two options:my.example.com
.The advice I needed and have not been able to find. I could kiss you. Or at least give you a fond nod.