.\"	$OpenBSD: acme-client.1,v 1.20 2017/01/28 17:53:17 jmc Exp $
.\"
.\" Copyright (c) 2016 Kristaps Dzonsons <kristaps@bsd.lv>
.\"
.\" Permission to use, copy, modify, and distribute this software for any
.\" purpose with or without fee is hereby granted, provided that the above
.\" copyright notice and this permission notice appear in all copies.
.\"
.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
.\"
.Dd $Mdocdate: January 28 2017 $
.Dt ACME-CLIENT 1
.Os
.Sh NAME
.Nm acme-client
.Nd ACME client
.Sh SYNOPSIS
.Nm acme-client
.Op Fl ADFnrv
.Op Fl f Ar configfile
.Ar domain
.Sh DESCRIPTION
The
.Nm
utility is an
Automatic Certificate Management Environment (ACME) client.
.Pp
The options are as follows:
.Bl -tag -width Ds
.It Fl A
Create a new RSA account key if one does not already exist.
.It Fl D
Create a new RSA domain key if one does not already exist.
.It Fl F
Force updating the certificate signature even if it's too soon.
.It Fl f Ar configfile
Specify an alternative configuration file.
.It Fl n
No operation: check and print configuration.
.It Fl r
Revoke the X509 certificate found in the certificates.
.It Fl v
Verbose operation.
Specify twice to also trace communication and data transfers.
.It Ar domain
The domain name.
.El
.Pp
.Nm
looks in its configuration for a
.Ar domain
section corresponding to the domain given as command line argument.
It then uses that configuration to retrieve a TLS certificate.
If the certificate already exists and is less than 30 days from expiry,
.Nm
will attempt to refresh the signature.
Before a certificate can be requested, an account key needs to be
created using the
.Fl A
argument.
The first time a certificate is requested, the RSA key needs to be created with
.Fl D .
.Pp
Challenges are used to verify that the submitter has access to the
registered domains.
.Nm
only implements the
.Dq http-01
challenge type, where a file is created within a directory accessible
by a locally-run web server.
The default challenge directory
.Pa /var/www/acme
can be served by
.Xr httpd 8
with this location block,
which will properly map response challenges:
.Bd -literal -offset indent
location "/.well-known/acme-challenge/*" {
	root "/acme"
	root strip 2
}
.Ed
.Sh FILES
.Bl -tag -width "/etc/acme-client.conf" -compact
.It Pa /etc/acme-client.conf
Default configuration.
.It Pa /var/www/acme
Default challengedir.
.El
.Sh EXIT STATUS
.Nm
returns 1 on failure, 2 if the certificates didn't change (up to date),
or 0 if certificates were changed (revoked or updated).
.Sh EXAMPLES
To create and submit a new key for a single domain, assuming that the
web server has already been configured to map the challenge directory
as above:
.Pp
.Dl # acme-client -vD www.example.com
.Pp
A daily
.Xr cron 8
job can renew the certificates:
.Bd -literal -offset indent
#! /bin/sh

acme-client www.example.com

if [ $? -eq 0 ]
then
	/etc/rc.d/httpd reload
fi
.Ed
.Sh SEE ALSO
.Xr openssl 1 ,
.Xr acme-client.conf 5 ,
.Xr httpd.conf 5
.Sh STANDARDS
.Rs
.%U https://tools.ietf.org/html/draft-ietf-acme-acme-03
.%T Automatic Certificate Management Environment (ACME)
.Re
.Sh AUTHORS
The
.Nm
utility was written by
.An Kristaps Dzonsons Aq Mt kristaps@bsd.lv .
.Sh BUGS
The challenge and certificate processes currently retain their (root)
privileges.
.Pp
For the time being,
.Nm
only supports RSA as an account key format.