···1+<chapter xmlns="http://docbook.org/ns/docbook"
2+ xmlns:xlink="http://www.w3.org/1999/xlink"
3+ xmlns:xi="http://www.w3.org/2001/XInclude"
4+ version="5.0"
5+ xml:id="module-security-acme">
6+7+<title>SSL/TLS Certificates with ACME</title>
8+9+<para>NixOS supports automatic domain validation & certificate
10+retrieval and renewal using the ACME protocol. This is currently only
11+implemented by and for Let's Encrypt. The alternative ACME client
12+<literal>simp_le</literal> is used under the hood.</para>
13+14+<section><title>Prerequisites</title>
15+16+<para>You need to have a running HTTP server for verification. The server must
17+have a webroot defined that can serve
18+<filename>.well-known/acme-challenge</filename>. This directory must be
19+writeable by the user that will run the ACME client.</para>
20+21+<para>For instance, this generic snippet could be used for Nginx:
22+23+<programlisting>
24+http {
25+ server {
26+ server_name _;
27+ listen 80;
28+ listen [::]:80;
29+30+ location /.well-known/acme-challenge {
31+ root /var/www/challenges;
32+ }
33+34+ location / {
35+ return 301 https://$host$request_uri;
36+ }
37+ }
38+}
39+</programlisting>
40+</para>
41+42+</section>
43+44+<section><title>Configuring</title>
45+46+<para>To enable ACME certificate retrieval & renewal for a certificate for
47+<literal>foo.example.com</literal>, add the following in your
48+<filename>configuration.nix</filename>:
49+50+<programlisting>
51+security.acme.certs."foo.example.com" = {
52+ webroot = "/var/www/challenges";
53+ email = "foo@example.com";
54+};
55+</programlisting>
56+</para>
57+58+<para>The private key <filename>key.pem</filename> and certificate
59+<filename>fullchain.pem</filename> will be put into
60+<filename>/var/lib/acme/foo.example.com</filename>. The target directory can
61+be configured with the option <literal>security.acme.directory</literal>.
62+</para>
63+64+<para>Refer to <xref linkend="ch-options" /> for all available configuration
65+options for the <literal>security.acme</literal> module.</para>
66+67+</section>
68+69+</chapter>