openwrt-packages-dist/net/travelmate/files/travelmate.vpn

#!/bin/sh
# vpn handler called by travelmate
# Copyright (c) 2020-2022 Dirk Brenken (dev@brenken.org)
# This is free software, licensed under the GNU General Public License v3.

# set (s)hellcheck exceptions
# shellcheck disable=1091,3040,3043

# Please note: you have to setup the package 'wireguard' or 'openvpn' before using this script

. "/lib/functions.sh"

export LC_ALL=C
export PATH="/usr/sbin:/usr/bin:/sbin:/bin"
set -o pipefail

vpn="${1}"
vpn_action="${2}"
vpn_service="${3}"
vpn_iface="${4}"
trm_maxwait="$(uci_get travelmate global trm_maxwait "30")"
trm_captiveurl="$(uci_get travelmate global trm_captiveurl "http://detectportal.firefox.com")"
trm_useragent="$(uci_get travelmate global trm_useragent "Mozilla/5.0 (Linux x86_64; rv:90.0) Gecko/20100101 Firefox/90.0")"
trm_logger="$(command -v logger)"
trm_fetch="$(command -v curl)"
trm_vpnfile="/var/state/travelmate.vpn"

f_net() {
	local json_rc result="net nok"

	json_rc="$(${trm_fetch} --user-agent "${trm_useragent}" --referer "http://www.example.com" --header "Cache-Control: no-cache, no-store, must-revalidate, max-age=0" --write-out "%{response_code}" --silent --output /dev/null --max-time $((trm_maxwait / 6)) "${trm_captiveurl}")"
	if [ "${json_rc}" = "200" ] || [ "${json_rc}" = "204" ]; then
		result="net ok"
	fi
	printf "%s" "${result}"
}

vpn_status="$(ubus -S call network.interface."${vpn_iface}" status 2>/dev/null | jsonfilter -q -l1 -e '@.up')"
if [ "${vpn}" = "1" ] && [ "${vpn_action}" = "enable" ] && [ "${vpn_status}" != "true" ]; then
	if [ "${vpn_service}" = "openvpn" ] && [ -x "/etc/init.d/openvpn" ]; then
		/etc/init.d/openvpn start
	fi
	ifup "${vpn_iface}"
	cnt=0
	while true; do
		vpn_status="$(ubus -S call network.interface."${vpn_iface}" status 2>/dev/null | jsonfilter -q -l1 -e '@.up')"
		if [ "${vpn_status}" = "true" ]; then
			net_status="$(f_net)"
			if [ "${net_status}" = "net ok" ]; then
				: >"${trm_vpnfile}"
				"${trm_logger}" -p "info" -t "trm-vpn  [${$}]" "${vpn_service} client connection enabled" 2>/dev/null
				break
			fi
		fi
		if [ "${cnt}" -ge "$((trm_maxwait / 3))" ]; then
			ifdown "${vpn_iface}"
			if [ "${vpn_service}" = "openvpn" ] && [ -x "/etc/init.d/openvpn" ]; then
				/etc/init.d/openvpn stop
			fi
			rm -f "${trm_vpnfile}"
			"${trm_logger}" -p "info" -t "trm-vpn  [${$}]" "${vpn_service} client connection can't be established" 2>/dev/null
			exit 1
		fi
		sleep 1
		cnt="$((cnt + 1))"
	done
elif { [ "${vpn}" != "1" ] && [ "${vpn_action}" = "enable" ]; } || [ "${vpn_action}" = "disable" ]; then
	ifdown "${vpn_iface}"
	if [ "${vpn_service}" = "openvpn" ] && [ -x "/etc/init.d/openvpn" ]; then
		/etc/init.d/openvpn stop
	fi
	rm -f "${trm_vpnfile}"
	"${trm_logger}" -p "info" -t "trm-vpn  [${$}]" "${vpn_service} client connection disabled" 2>/dev/null
fi