💾 Archived View for nox.im › posts › 2021 › 0702 › openbsd-webserver-with-httpd-and-letsencrypt captured on 2023-04-26 at 13:23:52. Gemini links have been rewritten to link to archived content
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Before starting with the acme-client and the httpd setup, I had created a Let's Encrypt account[1] with a registered account key.
1: created a Let's Encrypt account
add to `/etc/httpd.conf` the domain or default section the challenge path that is going to get hit for the certificate
location "/.well-known/acme-challenge/*" { root "/acme" request strip 2 directory no auto index }
and restart httpd
doas rcctl restart httpd
Then configure the acme client
doas vi /etc/acme-client.conf
api_url="https://acme-v02.api.letsencrypt.org/directory" authority letsencrypt { api url $api_url account key "/etc/acme/letsencrypt.pem" } domain nox.im { alternative names { www.nox.im } domain key "/etc/ssl/private/nox.im.key" domain full chain certificate "/etc/ssl/nox.im.fullchain.pem" sign with letsencrypt }
Try to get the certificate
doas acme-client -v nox.im
If everything worked you should see the command terminate with
... acme-client: /etc/ssl/nox.im.fullchain.pem: created
nice!
we then update the `/etc/httpd.conf` for the TLS key pair and redirect port 80 to https port 443:
ext_ip="*" server "nox.im" { alias "www.nox.im" listen on $ext_ip port 80 block return 301 "https://$SERVER_NAME$REQUEST_URI" } server "nox.im" { alias "www.nox.im" listen on $ext_ip tls port 443 hsts tls { certificate "/etc/ssl/nox.im.fullchain.pem" key "/etc/ssl/private/nox.im.key" } log style combined root "/htdocs/nox.im" location "/.well-known/acme-challenge/*" { root "/acme" request strip 2 directory no auto index } } #server "nox.im" { # listen on $ext_ip port 80 # root "/htdocs/nox.im" # location "/.well-known/acme-challenge/*" { # root "/acme" # request strip 2 # directory no auto index # } #} types { include "/usr/share/misc/mime.types" }
to test the configuration without stopping httpd (no downtime!) we can run
doas httpd -n
If that works, restart httpd and we should now have https available
https://nox.im
See the recent post on a simple web analytics dashboard with GoAccess[1] for httpd log based, server side analytics.
1: web analytics dashboard with GoAccess
We utilize periodic system maintenance daily which runs the user script /etc/daily.local, if it exists.
doas vi /etc/daily.local
#!/bin/sh acme-client -v nox.im rcctl reload httpd
and make it executable
doas chmod +x /etc/daily.local
The certificate is valid for 90 days, so it'll not do anything immediately but only renew it closer to expiration.
If your certificate doesn't renew you will get emailed by Let's Encrypt two weeks before expiry. It is best to just run the acme-client manually to diagnose the problem. I recently was messing with my keys and ran into the following issue.
acme-client -v nox.im api_url = "https://acme-v02.api.letsencrypt.org/directory" acme-client: /etc/ssl/private/nox.im.key: group read/writable or world read/writable chmod g-r /etc/ssl/private/nox.im.key
The SSL Server test performs an analysis of our server configuration, supported protocols, weak ciphers and its susceptibility to downgrade attacks. Our setup of OpenBSD httpd, libressl with Let's Encrypt effortlessly scores an A+ on SSL Labs[1].
SSL Labs A+ score for nox.im[1]
1: SSL Labs A+ score for nox.im
And thereby nox.im made the top list too.
SSL Labs recent top ranked servers[1]
1: SSL Labs recent top ranked servers
CAA DNS record allows to specify one or more Certification Authorities (CAs) to issue certificates for a given domain. CAA is specified in RFC6844[1] to improve of the public key infrastructure (PKI). Without CAA, any CA can issue a certificate for any domain name.
We can set a CAA via a DNS record called CAA (type 257) and restrict certificate issuance. For example, my nox.im CAA configuration for Let's Encrypt is as follows:
@ 10800 IN CAA 128 issue "letsencrypt.org"
CAs are expected to check this record and refuse issuance should they not find themselves on the whitelist.