#!/bin/sh
#
# (Un)registers systems accounts (users/groups).
#
# Arguments:	$ACTION = [run/targets]
#		$TARGET = [post-install/pre-remove]
#		$PKGNAME
#		$VERSION
#		$UPDATE = [yes/no]
#
ACTION="$1"
TARGET="$2"
PKGNAME="$3"
VERSION="$4"
UPDATE="$5"

export PATH="usr/sbin:usr/bin:/usr/sbin:/usr/bin:/sbin:/bin"

group_add() {
	local _grname _gid use_gid

	_grname="${1%:*}"
	_gid="${1#*:}"

	if [ "${_gid}" != "${_grname}" ]; then
		use_gid="gid ${_gid}"
	fi

	if ! getent group ${_grname} >/dev/null; then
		if [ -n "$use_gid" ]; then
			groupadd -r ${_grname} -g ${_gid} >/dev/null 2>&1
		else
			groupadd -r ${_grname} >/dev/null 2>&1
		fi
		if [ $? -eq 0 ]; then
			echo "Created ${_grname} ($use_gid) system group."
		else
			echo "Failed to create ${_grname} ($use_gid) system group!"
			exit 1
		fi
	fi
}

case "$ACTION" in
targets)
	echo "post-install pre-remove"
	;;
run)
	if [ -z "$system_accounts" -a -z "$system_groups" ]; then
		exit 0
	fi

	if [ -x sbin/useradd -o -x bin/useradd ]; then
		USERADD=1
	fi
	if [ -x sbin/usermod -o -x bin/usermod ]; then
		USERMOD=1
	fi
	if [ -x sbin/groupadd -o -x bin/groupadd ]; then
		GROUPADD=1
	fi
	if [ -x bin/getent -o -x sbin/getent ]; then
		GETENT=1
	fi
	if [ -x bin/passwd -o -x sbin/passwd ]; then
		PASSWD=1
	fi

	case "$TARGET" in
	post-install)
		# System groups required by a package.
		for grp in ${system_groups}; do
			if [ -z "$GROUPADD" -a -z "$GETENT" ]; then
				echo "WARNING: cannot create ${grp} system group (missing groupadd/getent)"
				echo "The following group must be created manually: $grp"
				continue
			fi
			group_add $grp
		done

		# System user/group required by a package.
		for acct in ${system_accounts}; do
			_uname="${acct%:*}"
			_uid="${acct#*:}"
			[ "${_uid}" != "${_uname}" ] && use_id="-u ${_uid} -g ${_uid}"

			eval homedir="\$${_uname}_homedir"
			eval shell="\$${_uname}_shell"
			eval descr="\$${_uname}_descr"
			eval groups="\$${_uname}_groups"
			eval pgroup="\$${_uname}_pgroup"
			[ -z "$homedir" ] && homedir="/var/empty"
			[ -z "$shell" ] && shell="/sbin/nologin"
			[ -z "$descr" ] && descr="${_uname} unprivileged user"
			[ -n "$groups" ] && user_groups="-G $groups"

			if [ -z "$USERADD" -a -z "$GETENT" -a -z "$PASSWD" ]; then
				echo "WARNING: cannot create ${acct} system user/group (missing useradd/getent/passwd)"
				echo "The following system account must be created:"
				echo "   Account: ${uname:-${_uid}} (uid: '${_uid}')"
				echo "   Description: '${descr}'"
				echo "   Homedir: '${homedir}'"
				echo "   Shell: '${shell}'"
				echo "   Additional groups: '${groups}'"
				continue
			fi

			group_add ${pgroup:-${acct}}

			if ! getent passwd ${_uname} >/dev/null; then
				useradd -c "$descr" -d "$homedir" -s "$shell" ${user_groups} \
					${pgroup:+-N} ${use_id:=-g ${pgroup:-${_uname}}} -r ${_uname} && \
					passwd -l ${_uname} >/dev/null 2>&1
				if [ $? -eq 0 ]; then
					echo "Created ${_uname} (${_uid}) system user."
				else
					echo "Failed to create ${acct} system user!"
					exit 1
				fi
			else
				if [ -z "$USERMOD" ]; then
					echo "WARNING: cannot update ${acct} system user/group (missing usermod)"
					continue
				fi
				usermod -c "${descr}" -s "${shell}" ${_uname} >/dev/null 2>&1
				if [ $? -eq 0 ]; then
					echo "Updated shell and comment for ${_uname} (${_uid}) system user."
				else
					echo "Failed to update shell and comment for ${acct} system user!"
					exit 1
				fi
			fi
		done
		;;
	pre-remove)
		if [ "$UPDATE" = "no" ]; then
			for acct in ${system_accounts}; do
				_uname="${acct%:*}"
				_uid="${acct#*:}"
				comment="$(getent passwd "${_uname}" |cut -d: -f5 |head -n1) - for uninstalled package ${PKGNAME}"
				if [ -z "$USERMOD" ]; then
					echo "WARNING: cannot disable ${acct} system user/group (missing usermod)"
					continue
				fi
				usermod -L -s /bin/false -c "${comment}" ${_uname} >/dev/null 2>&1
				if [ $? -eq 0 ]; then
					echo "Disabled ${_uname} (${_uid}) system user/group."
				fi
			done
		fi
		;;
	esac
	;;
*)
	exit 1
	;;
esac

exit 0