Handle already-applied routes gently

2 files changed, 17 insertions, 6 deletions

diff --git a/talpid-routing/src/unix/macos/mod.rs b/talpid-routing/src/unix/macos/mod.rs
index 9a4d8bb180..dc2f17b394 100644
--- a/talpid-routing/src/unix/macos/mod.rs
+++ b/talpid-routing/src/unix/macos/mod.rs
@@ -601,12 +601,14 @@ impl RouteManagerImpl {
     async fn add_route_with_record(&mut self, route: RouteMessage) -> Result<()> {
         let destination = RouteDestination::try_from(&route).map_err(Error::InvalidData)?;
 
-        self.routing_table
+        let add_result = self.routing_table
             .add_route(&route)
             .await
             .map_err(Error::AddRoute)?;
 
-        self.applied_routes.insert(destination, route);
+        if add_result == watch::AddResult::Ok {
+            self.applied_routes.insert(destination, route);
+        }
         Ok(())
     }
 
diff --git a/talpid-routing/src/unix/macos/watch.rs b/talpid-routing/src/unix/macos/watch.rs
index 70271a85d4..61c620b2f3 100644
--- a/talpid-routing/src/unix/macos/watch.rs
+++ b/talpid-routing/src/unix/macos/watch.rs
@@ -37,6 +37,15 @@ pub struct RoutingTable {
     socket: routing_socket::RoutingSocket,
 }
 
+/// Result of successfully adding a route
+#[derive(Debug, PartialEq, Copy, Clone)]
+pub enum AddResult {
+    /// A new route was created
+    Ok,
+    /// The route already exists
+    AlreadyExists,
+}
+
 impl RoutingTable {
     pub fn new() -> Result<Self> {
         let socket = routing_socket::RoutingSocket::new().map_err(Error::RoutingSocket)?;
@@ -63,14 +72,14 @@ impl RoutingTable {
         data::RouteSocketMessage::parse_message(msg_buf).map_err(Error::InvalidMessage)
     }
 
-    pub async fn add_route(&mut self, message: &RouteMessage) -> Result<()> {
+    pub async fn add_route(&mut self, message: &RouteMessage) -> Result<AddResult> {
         if let Ok(destination) = message.destination_ip() {
             if Some(destination.ip()) == message.gateway_ip() {
                 // Workaround that allows us to reach a wg peer on our router.
                 // If we don't do this, adding the route fails due to errno 49
                 // ("Can't assign requested address").
                 log::warn!("Ignoring route because the destination equals its gateway");
-                return Ok(());
+                return Ok(AddResult::AlreadyExists);
             }
         }
 
@@ -79,11 +88,11 @@ impl RoutingTable {
             .await;
 
         match msg {
-            Ok(RouteSocketMessage::AddRoute(_route)) => Ok(()),
+            Ok(RouteSocketMessage::AddRoute(_route)) => Ok(AddResult::Ok),
             Err(Error::Send(routing_socket::Error::Write(err)))
                 if err.kind() == io::ErrorKind::AlreadyExists =>
             {
-                Ok(())
+                Ok(AddResult::AlreadyExists)
             }
             Ok(anything_else) => {
                 log::error!("Unexpected route message: {anything_else:?}");