#!/bin/bash -e
#
# Univention Home Mounter
#  mount the homedir
#
# Copyright 2004-2013 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/>.

username="${1:-${USER:?neither \$1 nor \$USER}}"

eval "$(univention-config-registry shell ldap/hostdn)"

# Get the passwd line for current user.
# If a user has a numerical username, getent would treat the name
# as the uid and deliver consequently a wrong or an empty result.
case "$username" in
[0-9]*)
	if ldap_result=$(ldapsearch -x -ZZ -D "$ldap_hostdn" -y /etc/machine.secret -LLL uid="$username" homeDirectory uidNumber gidNumber |
			ldapsearch-wrap |
			ldapsearch-decode64)
	then
		pw_dir="$(echo "$ldap_result" | sed -ne 's|^homeDirectory: ||p')"
		pw_uid="$(echo "$ldap_result" | sed -ne 's|uidNumber: ||p')"
		pw_gid="$(echo "$ldap_result" | sed -ne 's|gidNumber: ||p')"
	else
		IFS=: read _ _ pw_uid pw_gid _ pw_dir _ <<<"$(awk -F: -v U="$username" '$1==U {print}' /etc/passwd)"
	fi
	;;
*)
	IFS=: read _ _ pw_uid pw_gid _ pw_dir _ <<<"$(getent passwd "$username")"
	;;
esac

[ -z "$pw_dir" ] && exit 1
[ "$pw_uid" -lt 1000 ] && exit 0
if REALHOME="$(readlink -f "$pw_dir")"
then
	mountpoint -q "$REALHOME" && exit 0
else
	REALHOME="$pw_dir"
fi

homeattr="$(ldapsearch -x -ZZ -D "$ldap_hostdn" -y /etc/machine.secret -z 1 "(&(objectClass=posixAccount)(objectClass=automount)(uid=$username))" automountInformation -LLL |
	ldapsearch-wrapper |
	sed -ne 's/^automountInformation: //p')"
if [ -n "$homeattr" ]
then
	homeattr="${homeattr#-r[ow] }"
	host="${homeattr%%:*}"
	path="${homeattr#*:}"
	if [ -z "$host" ] || [ -z "$path" ]
	then
		logger "Bad information in LDAP. Not mounting home directory."
		exit 1
	fi

	if ( [ "$host" = "$(hostname -f)" ] || [ "$host" = "$(hostname -s)" ] ) && \
			[ "$(readlink -f "$path")" = "$REALHOME" ]
	then
		logger "Home directory is local."
		exit 0
	fi
fi

if ! [ -e "$REALHOME" ]
then
	logger "Create homdir $REALHOME"
	# Use the username as owner instead of the uid.
	# In case a numerical username identical with the
	# given uid exists, chown would set the numerical username
	# as owner.
	install -d -o "$username" -g "$pw_gid" -m 0711 "$REALHOME"
fi

[ -z "$homeattr" ] && exit 0

if mount -t nfs "$host:$path" "$REALHOME"
then
	dotlockfile -l /var/lib/univention-home-mounter/mounts.lock
	echo "$REALHOME $(date +%s)" >> /var/lib/univention-home-mounter/mounts
	dotlockfile -u /var/lib/univention-home-mounter/mounts.lock
else
	logger "Failed to mount home directory: $pw_dir"
	exit 1
fi