.lf 1 stdin
.TH SLAPO-AUTOCA 5 "2024/01/29" "OpenLDAP 2.6.7"
.\" Copyright 2009-2022 The OpenLDAP Foundation All Rights Reserved.
.\" Copyright 2009-2018 Howard Chu All Rights Reserved.
.\" Copying restrictions apply.  See COPYRIGHT/LICENSE.
.\" $OpenLDAP$
.SH NAME
slapo\-autoca \- Automatic Certificate Authority overlay to slapd
.SH SYNOPSIS
/etc/openldap/slapd.conf
.SH DESCRIPTION
The Automatic CA overlay generates X.509 certificate/key pairs for
entries in the directory. The DN of a generated certificate is
identical to the DN of the entry containing it. On startup it
looks for a CA certificate and key in the suffix entry of the
database which it will use to sign all subsequently generated
certificates. A new CA certificate and key will be generated
and stored in the suffix entry if none already exists. The CA
certificate is stored in the cACertificate;binary attribute of
the suffix entry, and the private key is stored in the
cAPrivateKey;binary attribute of the suffix entry. These
attributes may be overwritten if some other CA certificate/key
pair is desired for use.
.LP
Certificates for users and servers are generated on demand using
a Search request returning only the userCertificate;binary and
userPrivateKey;binary attributes. Any Search for anything besides
exactly these two attributes is ignored by the overlay. Note that
these values are stored in ASN.1 DER form in the directory so the
";binary" attribute option is mandatory.
.LP
Entries that do not belong to selected objectClasses will be
ignored by the overlay. By default, entries of objectClass
.B person
will be treated as users, and entries of objectClass
.B ipHost
will be treated as servers. There are slight differences in the
set of X.509V3 certificate extensions added to the certificate
between users and servers.
.LP
The CA's private key is stored in a
.B cAPrivateKey
attribute, and user and server private keys are stored in the
.B userPrivateKey
attribute. The private key values are encoded in PKCS#8 format.
It is essential that access to these attributes be
properly secured with ACLs. Both of these attributes inherit
from the
.B pKCS8PrivateKey
attribute, so it is sufficient to use a single ACL rule like

.nf
        access to attrs=pKCS8PrivateKey by self ssf=128 write
.fi

at the beginning of the rules.
.LP
Currently there is no automated management for expiration or revocation.
Obsolete certificates and keys must be manually removed by deleting
an entry's userCertificate and userPrivateKey attributes.

.SH CONFIGURATION
These
.B slapd.conf
options apply to the Automatic CA overlay.
They should appear after the
.B overlay
directive.
.TP
.B userClass <objectClass>
Specify the objectClass to be treated as user entries.
.TP
.B serverClass <objectClass>
Specify the objectClass to be treated as server entries.
.TP
.B userKeybits <integer>
Specify the size of the private key to use for user certificates.
The default is 2048 and the minimum is 512.
.TP
.B serverKeybits <integer>
Specify the size of the private key to use for server certificates.
The default is 2048 and the minimum is 512.
.TP
.B caKeybits <integer>
Specify the size of the private key to use for the CA certificate.
The default is 2048 and the minimum is 512.
.TP
.B userDays <integer>
Specify the duration for a user certificate's validity.
The default is 365, 1 year.
.TP
.B serverDays <integer>
Specify the duration for a server certificate's validity.
The default is 1826, 5 years.
.TP
.B caDays <integer>
Specify the duration for the CA certificate's validity.
The default is 3652, 10 years.
.TP
.B localDN <DN>
Specify the DN of an entry that represents this server. Requests
to generate a certificate/key pair for this DN will also install
the certificate and key into slapd's TLS settings in cn=config
for immediate use.

.SH EXAMPLES
.nf
  database mdb
  ...
  overlay autoca
  caKeybits 4096
.fi
.SH FILES
.TP
/etc/openldap/slapd.conf
default slapd configuration file
.SH SEE ALSO
.BR slapd.conf (5),
.BR slapd\-config (5).
.SH AUTHOR
Howard Chu