#!/bin/sh
#
# Univention Samba 4
#
# Copyright 2012-2017 Univention GmbH
#
# http://www.univention.de/
#
# All rights reserved.
#
# The source code of this program is made available
# under the terms of the GNU Affero General Public License version 3
# (GNU AGPL V3) as published by the Free Software Foundation.
#
# Binary versions of this program provided by Univention to you as
# well as other copyrighted, protected or trademarked materials like
# Logos, graphics, fonts, specific documentations and configurations,
# cryptographic keys etc. are subject to a license agreement between
# you and Univention and not subject to the GNU AGPL V3.
#
# In the case you use this program under the terms of the GNU AGPL V3,
# the program is provided in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public
# License with the Debian GNU/Linux or Univention distribution in file
# /usr/share/common-licenses/AGPL-3; if not, see
# <http://www.gnu.org/licenses/>.

eval "$(univention-config-registry shell)"

set_machine_secret() {
	## 1. store password locally in secrets.ldb
	old_kvno=$(ldbsearch -H /var/lib/samba/private/sam.ldb samAccountName="${hostname}\$" msDS-KeyVersionNumber | sed -n 's/msDS-KeyVersionNumber: \(.*\)/\1/p')
	new_kvno=$(($old_kvno + 1))

	ldbmodify -H /var/lib/samba/private/secrets.ldb <<-%EOF
	dn: flatname=${windows_domain},cn=Primary Domains
	changetype: modify
	replace: secret
	secret:< file:///etc/machine.secret
	-
	replace: msDS-KeyVersionNumber
	msDS-KeyVersionNumber: $new_kvno
	-
	%EOF

	## 2. replace random machine secret in SAM with /etc/machine.secret
	samba-tool user setpassword "${hostname}\$" --newpassword="$(cat /etc/machine.secret)"
}

if [ "$1" = "postchange" ]; then
	set_machine_secret

	test -x /etc/init.d/samba-ad-dc && invoke-rc.d samba-ad-dc restart
fi
