#!/bin/sh
# vpn handler called by travelmate
# Copyright (c) 2020-2026 Dirk Brenken (dev@brenken.org)
# This is free software, licensed under the GNU General Public License v3.

# set (s)hellcheck exceptions
# shellcheck disable=all

export LC_ALL=C
export PATH="/usr/sbin:/usr/bin:/sbin:/bin"
vpn="${1}"
vpn_action="${2}"
vpn_service="${3}"
vpn_iface="${4}"
vpn_instance="${5}"
vpn_status=""
trm_funlib="/usr/lib/travelmate-functions.sh"
if [ -z "${trm_bver}" ]; then
	. "${trm_funlib}"
	f_conf
fi

f_net() {
	local json_rc
	json_rc="$("${trm_fetchcmd}" ${trm_fetchparm} --user-agent "${trm_useragent}" --header "Cache-Control: no-cache, no-store, must-revalidate, max-age=0" --write-out "%{response_code}" --output /dev/null "${trm_captiveurl}")"
	if [ "${json_rc}" = "200" ] || [ "${json_rc}" = "204" ]; then
		json_rc="net ok"
	fi
	printf "%s" "${json_rc}"
}

if [ "${vpn}" = "1" ] && [ "${vpn_action%_*}" = "enable" ]; then
	if [ "${vpn_action}" = "enable_keep" ]; then
		vpn_status="$("${trm_ubuscmd}" -S call network.interface."${vpn_iface}" status 2>/dev/null | "${trm_jsoncmd}" -ql1 -e '@.up')"
	fi
	f_log "info" "start vpn processing (vpn: ${vpn:-"-"}, action: ${vpn_action:-"-"}, interface: ${vpn_iface:-"-"}, instance: ${vpn_instance:-"-"}, status: ${vpn_status:-"-"})"
	if [ "${vpn_action}" = "enable" ] || [ "${vpn_status}" != "true" ]; then
		if [ "${vpn_status}" != "true" ]; then
			/sbin/ifdown "${vpn_iface}"
			"${trm_ubuscmd}" -S call network.interface."${vpn_iface}" remove >/dev/null 2>&1
			if [ "${vpn_service}" = "openvpn" ] && [ -n "${vpn_instance}" ] && [ -x "/etc/init.d/openvpn" ]; then
				if /etc/init.d/openvpn running "${vpn_instance}"; then
					/etc/init.d/openvpn stop "${vpn_instance}"
				fi
				/etc/init.d/openvpn start "${vpn_instance}"
			fi
		fi
		sleep 1
		/sbin/ifup "${vpn_iface}"
		if ! "${trm_ubuscmd}" -t "$((trm_maxwait / 6))" wait_for network.interface."${vpn_iface}" >/dev/null 2>&1; then
			f_log "info" "travelmate vpn interface '${vpn_iface}' does not appear on ubus on ifup event"
		fi
		cnt="0"
		while :; do
			vpn_status="$("${trm_ubuscmd}" -S call network.interface."${vpn_iface}" status 2>/dev/null | "${trm_jsoncmd}" -ql1 -e '@.up')"
			if [ "${vpn_status}" = "true" ]; then
				net_status="$(f_net)"
				if [ "${net_status}" = "net ok" ]; then
					: >"${trm_vpnfile}"
					f_log "info" "${vpn_service} client connection enabled '${vpn_iface}/${vpn_instance:-"-"}'"
					break
				fi
			fi
			if [ "${cnt}" -ge "$((trm_maxwait / 3))" ]; then
				/sbin/ifdown "${vpn_iface}"
				"${trm_ubuscmd}" -S call network.interface."${vpn_iface}" remove >/dev/null 2>&1
				if [ "${vpn_service}" = "openvpn" ] && [ -n "${vpn_instance}" ] && [ -x "/etc/init.d/openvpn" ] && /etc/init.d/openvpn running "${vpn_instance}"; then
					/etc/init.d/openvpn stop "${vpn_instance}"
				fi
				rm -f "${trm_vpnfile}"
				f_log "info" "${vpn_service} client connection can't be established '${vpn_iface}/${vpn_instance:-"-"}, rc: ${net_status:-"-"}'"
				exit 1
			fi
			cnt="$((cnt + 1))"
			sleep 1
		done
	fi
elif { [ "${vpn}" != "1" ] && [ "${vpn_action%_*}" = "enable" ]; } || [ "${vpn_action}" = "disable" ]; then
	/sbin/ifdown "${vpn_iface}"
	"${trm_ubuscmd}" -S call network.interface."${vpn_iface}" remove >/dev/null 2>&1
	if [ "${vpn_service}" = "openvpn" ] && [ -n "${vpn_instance}" ] && [ -x "/etc/init.d/openvpn" ] && /etc/init.d/openvpn running "${vpn_instance}"; then
		/etc/init.d/openvpn stop "${vpn_instance}"
	fi
	rm -f "${trm_vpnfile}"
	f_log "info" "${vpn_service} client connection disabled '${vpn_iface}/${vpn_instance:-"-"}'"
fi