Like almost any individual on Earth involved a little bit in open-source, I use Let's Encrypt to generate my web certificates.
The first client I used for this was acme-client. It was conveniently available as FreeBSD's security/acme-client port but it has been removed. The reason, as far as I understand, is a bit silly: acme-client has been imported in OpenBSD and is now maintained there. The code on the original website is not updated anymore so the port has been removed. (It's a bit more work to maintain a tool from OpenBSD as a port, as someone needs to manually extract it from time to time and store it somewhere, I guess that's the fundamental reason.)
Anyway I had to find something else and after a bit of googling, I found a replacement: acme.sh, which is packaged as security/acme.sh. At first this is a bit scary (7000 lines of shell script, but well people have reported it works well and it's simple, so I gave it a try.
So here is how set it up (note that the ordering is important):
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First you need to configure you web server so that Let's Encrypt's service can read the challenge and verify the domain you claim is indeed yours. In my case, with Nginx:
# This host only exist on port 443. Just accept Let's Encrypt challenges # in plain text and redirect anything else to the port 443. server { listen 80; server_name foo.chchile.org; access_log /var/log/nginx/foo-access.log; error_log /var/log/nginx/foo-error.log info; allow all; root /var/empty; location ^~ /.well-known/acme-challenge/ { alias /usr/local/www/acme/.well-known/acme-challenge/; } location / { return 301 https://foo.chchile.org$request_uri; } } -
Then you can run
acme.shto issue the certificate. It's really straightforward:# /usr/local/sbin/acme.sh --issue -d foo.chchile.org -w /usr/local/www/acme [Sat Feb 15 21:40:18 UTC 2020] Create account key ok. [Sat Feb 15 21:40:18 UTC 2020] Registering account [Sat Feb 15 21:40:19 UTC 2020] Registered [Sat Feb 15 21:40:19 UTC 2020] ACCOUNT_THUMBPRINT='...' [Sat Feb 15 21:40:19 UTC 2020] Creating domain key [Sat Feb 15 21:40:19 UTC 2020] The domain key is here: /root/.acme.sh/foo.chchile.org/foo.chchile.org.key [Sat Feb 15 21:40:19 UTC 2020] Single domain='foo.chchile.org' [Sat Feb 15 21:40:19 UTC 2020] Getting domain auth token for each domain [Sat Feb 15 21:40:20 UTC 2020] Getting webroot for domain='foo.chchile.org' [Sat Feb 15 21:40:20 UTC 2020] Verifying: foo.chchile.org [Sat Feb 15 21:40:24 UTC 2020] Success [Sat Feb 15 21:40:24 UTC 2020] Verify finished, start to sign. [Sat Feb 15 21:40:24 UTC 2020] Lets finalize the order, Le_OrderFinalize: https://acme-v02.api.letsencrypt.org/acme/finalize/78264375/2343222 453 [Sat Feb 15 21:40:25 UTC 2020] Download cert, Le_LinkCert: https://acme-v02.api.letsencrypt.org/acme/cert/04236a2f1bd00075bda7c3ed8bb9d2953b0 0 [Sat Feb 15 21:40:25 UTC 2020] Cert success. -----BEGIN CERTIFICATE----- [...] -----END CERTIFICATE----- [Sat Feb 15 21:40:25 UTC 2020] Your cert is in /root/.acme.sh/foo.chchile.org/foo.chchile.org.cer [Sat Feb 15 21:40:25 UTC 2020] Your cert key is in /root/.acme.sh/foo.chchile.org/foo.chchile.org.key [Sat Feb 15 21:40:25 UTC 2020] The intermediate CA cert is in /root/.acme.sh/foo.chchile.org/ca.cer [Sat Feb 15 21:40:25 UTC 2020] And the full chain certs is there: /root/.acme.sh/foo.chchile.org/fullchain.cer -
Now, let's configure the desired certificate paths in Nginx (there's not there yet, this will be the next step):
server { listen 443 ssl; server_name foo.chchile.org; access_log /var/log/nginx/foo-access.log; error_log /var/log/nginx/foo-error.log debug; ssl_certificate /usr/local/etc/ssl/acme/foo.chchile.org/fullchain.pem; ssl_certificate_key /usr/local/etc/ssl/acme/private/foo.chchile.org/privkey.pem; ssl_session_timeout 5m; ssl_protocols TLSv1.1 TLSv1.2; ssl_ciphers HIGH:!aNULL:!MD5; ssl_prefer_server_ciphers on; [...] } -
It's almost done.
acme.shuses/root/.acme.shas its work space. The certificate and the key are there but it's not advised to use them as is since the internal layout may chance in the future. So you need to install (read "copy") the certificate:# /usr/local/sbin/acme.sh --install-cert -d foo.chchile.org \ --key-file /usr/local/etc/ssl/acme/private/foo.chchile.org/privkey.pem \ --cert-file /usr/local/etc/ssl/acme/foo.chchile.org/cert.pem \ --fullchain-file /usr/local/etc/ssl/acme/foo.chchile.org/fullchain.pem \ --reloadcmd "service nginx restart" [Sat Feb 15 21:42:24 UTC 2020] Installing cert to:/usr/local/etc/ssl/acme/foo.chchile.org/cert.pem [Sat Feb 15 21:42:24 UTC 2020] Installing key to:/usr/local/etc/ssl/acme/private/foo.chchile.org/privkey.pem [Sat Feb 15 21:42:24 UTC 2020] Installing full chain to:/usr/local/etc/ssl/acme/foo.chchile.org/fullchain.pem [Sat Feb 15 21:42:24 UTC 2020] Run reload cmd: service nginx restart Performing sanity check on nginx configuration: nginx: the configuration file /usr/local/etc/nginx/nginx.conf syntax is ok nginx: configuration file /usr/local/etc/nginx/nginx.conf test is successful Stopping nginx. Waiting for PIDS: 29714. Performing sanity check on nginx configuration: nginx: the configuration file /usr/local/etc/nginx/nginx.conf syntax is ok nginx: configuration file /usr/local/etc/nginx/nginx.conf test is successful Starting nginx. [Sat Feb 15 21:42:24 UTC 2020] Reload success -
And finally, set up a cron job to renew the certificate whenever it's needed. That's where
acme.shis neat, everything you typed above has been recorded in/root/acme.sh, so the crontab(5) line just looks like:0 0 * * * root /usr/local/sbin/acme.sh --cron > /dev/null
