[LEDE-DEV] [PATCH] wireguard: add distinction for remote and local endpoint ip

[Thomas Huehn]

This patch fixes a bug when someone tries to set up a Wireguard tunnel
to an endpoint where its ip belongs to a local subnet, e.g. in a Freifunk
olsr mesh. The call of proto_add_host_dependency() is just needed in cases
where the endpoint is reachable via a default gateway but not in such cases
where the endpoint is part of a local subnet.

Signed-off-by: Thomas Huehn <thomas at net.t-labs.tu-berlin.de>
---
 package/network/services/wireguard/files/wireguard.sh | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/package/network/services/wireguard/files/wireguard.sh b/package/network/services/wireguard/files/wireguard.sh
index 7b18a2e0ecdb..36ed80d9e7aa 100644
--- a/package/network/services/wireguard/files/wireguard.sh
+++ b/package/network/services/wireguard/files/wireguard.sh
@@ -16,6 +16,10 @@ fi
   init_proto "$@"
 }
 
+is_remote_ip() {
+     ip route get $1 | grep "via $(ip route | grep -m1 default | cut -d" " -f3)"
+}
+
 
 proto_wireguard_init_config() {
   proto_config_add_string "private_key"
@@ -174,7 +178,9 @@ proto_wireguard_setup() {
     sed -E 's/\[?([0-9.:a-f]+)\]?:([0-9]+)/\1 \2/' | \
     while IFS=$'\t ' read -r key address port; do
     [ -n "${port}" ] || continue
-    proto_add_host_dependency "${config}" "${address}"
+    is_remote_ip ${address} && {
+      logger -t Wireguard "no local route to endpoint - call proto_add_host_dependency()"
+      proto_add_host_dependency "${config}" "${address}"
   done
 
   proto_send_update "${config}"
-- 
2.16.2