ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/package/network/utils/wireguard-tools/files/wireguard_watchdog b/package/network/utils/wireguard-tools/files/wireguard_watchdog
new file mode 100644
index 0000000..fc90f4a
--- /dev/null
+++ b/package/network/utils/wireguard-tools/files/wireguard_watchdog
@@ -0,0 +1,68 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+#
+# Copyright (C) 2018 Aleksandr V. Piskunov <aleksandr.v.piskunov@gmail.com>.
+# Copyright (C) 2015-2018 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+#
+# This watchdog script tries to re-resolve hostnames for inactive WireGuard peers.
+# Use it for peers with a frequently changing dynamic IP.
+# persistent_keepalive must be set, recommended value is 25 seconds.
+#
+# Run this script from cron every minute:
+# echo '* * * * * /usr/bin/wireguard_watchdog' >> /etc/crontabs/root
+
+
+. /lib/functions.sh
+
+check_peer_activity() {
+ local cfg=$1
+ local iface=$2
+ local disabled
+ local public_key
+ local endpoint_host
+ local endpoint_port
+ local persistent_keepalive
+ local last_handshake
+ local idle_seconds
+
+ config_get_bool disabled "${cfg}" "disabled" 0
+ config_get public_key "${cfg}" "public_key"
+ config_get endpoint_host "${cfg}" "endpoint_host"
+ config_get endpoint_port "${cfg}" "endpoint_port"
+
+ if [ "${disabled}" -eq 1 ]; then
+ # skip disabled peers
+ return 0
+ fi
+
+ persistent_keepalive=$(wg show ${iface} persistent-keepalive | grep ${public_key} | awk '{print $2}')
+
+ # only process peers with endpoints and keepalive set
+ [ -z ${endpoint_host} ] && return 0;
+ [ -z ${persistent_keepalive} -o ${persistent_keepalive} = "off" ] && return 0;
+
+ # skip IP addresses
+ # check taken from packages/net/ddns-scripts/files/dynamic_dns_functions.sh
+ local IPV4_REGEX="[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}"
+ local IPV6_REGEX="\(\([0-9A-Fa-f]\{1,4\}:\)\{1,\}\)\(\([0-9A-Fa-f]\{1,4\}\)\{0,1\}\)\(\(:[0-9A-Fa-f]\{1,4\}\)\{1,\}\)"
+ local IPV4=$(echo ${endpoint_host} | grep -m 1 -o "$IPV4_REGEX$") # do not detect ip in 0.0.0.0.example.com
+ local IPV6=$(echo ${endpoint_host} | grep -m 1 -o "$IPV6_REGEX")
+ [ -n "${IPV4}" -o -n "${IPV6}" ] && return 0;
+
+ # re-resolve endpoint hostname if not responding for too long
+ last_handshake=$(wg show ${iface} latest-handshakes | grep ${public_key} | awk '{print $2}')
+ [ -z ${last_handshake} ] && return 0;
+ idle_seconds=$(($(date +%s)-${last_handshake}))
+ [ ${idle_seconds} -lt 150 ] && return 0;
+ logger -t "wireguard_monitor" "${iface} endpoint ${endpoint_host}:${endpoint_port} is not responding for ${idle_seconds} seconds, trying to re-resolve hostname"
+ wg set ${iface} peer ${public_key} endpoint "${endpoint_host}:${endpoint_port}"
+}
+
+# query ubus for all active wireguard interfaces
+eval $(ubus -S call network.interface dump | jsonfilter -e 'wg_ifaces=@.interface[@.up=true && @.proto="wireguard"].interface')
+
+# check every peer in every active wireguard interface
+config_load network
+for iface in $wg_ifaces; do
+ config_foreach check_peer_activity "wireguard_${iface}" "${iface}"
+done