openldap/contrib/slapd-modules/smbk5pwd

Copyright 2004-2005 Howard Chu, Symas Corp. All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted only as authorized by the OpenLDAP
Public License.

A copy of this license is available in the file LICENSE in the
top-level directory of the distribution or, alternatively, at
<http://www.OpenLDAP.org/license.html>.

This directory contains a slapd overlay, smbk5pwd, that extends the
PasswordModify Extended Operation to update Kerberos keys and Samba
password hashes for an LDAP user.

The Kerberos support is written for Heimdal using its hdb-ldap backend.
If a PasswordModify is performed on an entry that has the krb5KDCEntry
objectclass, then the krb5Key and krb5KeyVersionNumber will be updated
using the new password in the PasswordModify request. Additionally, a
new "{K5KEY}" password hash mechanism is provided. For krb5KDCEntries that
have this hash specifier in their userPassword attribute, Simple Binds
will be checked against the Kerberos keys of the Entry. No data is
needed after the "{K5KEY}" hash specifier in the userPassword, it is
looked up from the Entry directly.

The Samba support is written using the Samba 3.0 LDAP schema. If a
PasswordModify is performed on an entry that has the sambaSamAccount
objectclass, then the sambaLMPassword, sambaNTPassword, and sambaPwdLastSet
attributes will be updated accordingly.

To use the overlay, add:

	include <path to>/krb5-kdc.schema
	include <path to>/samba.schema

	moduleload <path to>smbk5pwd.so
	...

	database bdb
	...
	overlay smbk5pwd

to your slapd configuration file. (You should obtain the necessary schema
files from the Heimdal and/or Samba distributions. At this time, there
are several known errors in these schema files that you will have to
correct before they will load in slapd.  As of Samba 3.0 the schema looks
fine as shipped.)

All modules compiled in (i.e. krb5 and samba) are enabled; the statement

	smbk5pwd-enable		<module>

can be used to enable only the desired one(s); legal values for <module>
are "krb5" and "samba", if they are respectively enabled by defining
DO_KRB5 and DO_SAMBA.

The samba module also supports the

	smbk5pwd-must-change	<seconds>

which sets the "sambaPwdMustChange" attribute accordingly to force passwd
expiry.  A value of 0 disables this feature.

The overlay now supports table-driven configuration, and thus can be run-time
loaded and configured via back-config.  The layout of the entry is

	# {0}smbk5pwd, {1}bdb, config
	dn: olcOverlay={0}smbk5pwd,olcDatabase={1}bdb,cn=config
	objectClass: olcOverlayConfig
	objectClass: olcSmbK5PwdConfig
	olcOverlay: {0}smbk5pwd
	olcSmbK5PwdEnable: krb5
	olcSmbK5PwdEnable: samba
	olcSmbK5PwdMustChange: 2592000

which enables both krb5 and samba modules with a password expiry time
of 30 days.

The provided Makefile builds both Kerberos and Samba support by default.
You must edit the Makefile to insure that the correct include and library
paths are used. You can change the DEFS macro if you only want one or the
other of Kerberos or Samba support.

This overlay is only set up to be built as a dynamically loaded module.
On most platforms, in order for the module to be usable, all of the 
library dependencies must also be available as shared libraries.

If you need to build the overlay statically, you will have to move it into the
slapd/overlays directory and edit the Makefile and overlays.c to reference
it. You will also have to define SLAPD_OVER_SMBK5PWD to SLAPD_MOD_STATIC,
and add the relevant libraries to the main slapd link command.