openvpn: fix invoking user up & down commands from hotplug wrapper

This commit adds a number of fixes to the OpenVPN up/down hotplug command
wrapper which currently fails to actually invoke user defined up and down
commands for uci configurations not using external native configurations.

 - Use the `--setenv` to pass the user configured `up` and `down` commands
   as `user_up` and `user_down` environment variables respectively

 - Instead of attempting to scrape the `up` and `down` settings from the
   (possibly generated) native OpenVPN configuration in
   `/etc/hotplug.d/openvpn/01-user`, read them from the respective
   environment variables instead

 - Fix parsing of native configuration values in `get_openvpn_option()`;
   first try to parse a given setting as single quoted value, then as
   double quoted and finally as non-quoted, potentially white-space
   escaped one. This ensures that `up '/bin/foo'` is interpreted as
   `/bin/foo` and not `'/bin/foo'`

Ref: https://forum.openwrt.org/t/openvpn-up-down-configuration-ignored/91126


Supersedes: #15121, #15284
Signed-off-by: Jo-Philipp Wich <jo@mein.io>
(cherry-picked from commit 7f065a94)

net/openvpn/Makefile

@@ -10,7 +10,7 @@ include $(TOPDIR)/rules.mk
 PKG_NAME:=openvpn
 
 PKG_VERSION:=2.5.1
-PKG_RELEASE:=2
+PKG_RELEASE:=3
 
 PKG_SOURCE_URL:=\
 	https://build.openvpn.net/downloads/releases/ \

net/openvpn/files/etc/hotplug.d/openvpn/01-user

 #!/bin/sh
 
-. /lib/functions/openvpn.sh
-
 [ -e "/etc/openvpn.user" ] && {
 	env -i ACTION="$ACTION" INSTANCE="$INSTANCE" \
 		/bin/sh \
@@ -11,12 +9,14 @@
 
 # Wrap user defined scripts on up/down events
 case "$ACTION" in
-	up|down)
-		if get_openvpn_option "$config" command "$ACTION"; then
-			shift
-			exec /bin/sh -c "$command $*"
-		fi
-	;;
+	up) command=$user_up ;;
+	down) command=$user_down ;;
+	*) command= ;;
 esac
 
+if [ -n "$command" ]; then
+	shift
+	exec /bin/sh -c "$command $*"
+fi
+
 exit 0

net/openvpn/files/lib/functions/openvpn.sh

@@ -5,9 +5,9 @@ get_openvpn_option() {
 	local variable="$2"
 	local option="$3"
 
-	local value="$(sed -rne 's/^[ \t]*'"$option"'[ \t]+(([^ \t\\]|\\.)+)[ \t]*$/\1/p' "$config" | tail -n1 | sed -re 's/\\(.)/\1/g')"
-	[ -n "$value" ] || value="$(sed -rne 's/^[ \t]*'"$option"'[ \t]+'"'([^']+)'"'[ \t]*$/\1/p' "$config" | tail -n1)"
+	local value="$(sed -rne 's/^[ \t]*'"$option"'[ \t]+'"'([^']+)'"'[ \t]*$/\1/p' "$config" | tail -n1)"
 	[ -n "$value" ] || value="$(sed -rne 's/^[ \t]*'"$option"'[ \t]+"(([^"\\]|\\.)+)"[ \t]*$/\1/p' "$config" | tail -n1 | sed -re 's/\\(.)/\1/g')"
+	[ -n "$value" ] || value="$(sed -rne 's/^[ \t]*'"$option"'[ \t]+(([^ \t\\]|\\.)+)[ \t]*$/\1/p' "$config" | tail -n1 | sed -re 's/\\(.)/\1/g')"
 	[ -n "$value" ] || return 1
 
 	export -n "$variable=$value"

net/openvpn/files/openvpn.init

@@ -141,6 +141,8 @@ openvpn_add_instance() {
 	local dir="$2"
 	local conf="$3"
 	local security="$4"
+	local up="$5"
+	local down="$6"
 
 	procd_open_instance "$name"
 	procd_set_param command "$PROG"	\
@@ -150,6 +152,8 @@ openvpn_add_instance() {
 		--config "$conf" \
 		--up "/usr/libexec/openvpn-hotplug up $name" \
 		--down "/usr/libexec/openvpn-hotplug down $name" \
+		${up:+--setenv user_up "$up"} \
+		${down:+--setenv user_down "$down"} \
 		--script-security "${security:-2}" \
 		$(openvpn_get_dev "$name" "$conf") \
 		$(openvpn_get_credentials "$name" "$conf")
@@ -173,14 +177,18 @@ start_instance() {
 		return 1
 	}
 
-	local script_security
+	local up down script_security
+	config_get up "$s" up
+	config_get down "$s" down
 	config_get script_security "$s" script_security
 
 	[ ! -d "/var/run" ] && mkdir -p "/var/run"
 
 	if [ ! -z "$config" ]; then
 		append UCI_STARTED "$config" "$LIST_SEP"
-		openvpn_add_instance "$s" "${config%/*}" "$config" "$script_security"
+		[ -n "$up" ] || get_openvpn_option "$config" up up
+		[ -n "$down" ] || get_openvpn_option "$config" down down
+		openvpn_add_instance "$s" "${config%/*}" "$config" "$script_security" "$up" "$down"
 		return
 	fi
 
@@ -190,7 +198,7 @@ start_instance() {
 	append_params "$s" $OPENVPN_PARAMS
 	append_list "$s" $OPENVPN_LIST
 
-	openvpn_add_instance "$s" "/var/etc" "openvpn-$s.conf" "$script_security"
+	openvpn_add_instance "$s" "/var/etc" "openvpn-$s.conf" "$script_security" "$up" "$down"
 }
 
 start_service() {
@@ -207,6 +215,7 @@ start_service() {
 		fi
 	}
 
+	. /lib/functions/openvpn.sh
 	. /usr/share/openvpn/openvpn.options
 	config_load 'openvpn'
 
@@ -216,7 +225,7 @@ start_service() {
 	else
 		config_foreach start_instance 'openvpn'
 
-		local path name
+		local path name up down
 		for path in /etc/openvpn/*.conf; do
 			if [ -f "$path" ]; then
 				name="${path##*/}"; name="${name%.conf}"
@@ -231,7 +240,9 @@ start_service() {
 					continue
 				fi
 
-				openvpn_add_instance "$name" "${path%/*}" "$path"
+				get_openvpn_option "$path" up up || up=""
+				get_openvpn_option "$path" down down || down=""
+				openvpn_add_instance "$name" "${path%/*}" "$path" "" "$up" "$down"
 			fi
 		done
 	fi