Add the recent wireguard endpoint to NAT candidates if a peer has an …

…endpoint override

server/src/api/mod.rs

@@ -6,13 +6,24 @@ pub mod admin;
 pub mod user;
 
 /// Inject the collected endpoints from the WG interface into a list of peers.
-/// This is essentially what adds NAT holepunching functionality.
+/// This is essentially what adds NAT holepunching functionality. If a peer
+/// already has an endpoint specified (by calling the override-endpoint) API,
+/// the relatively recent wireguard endpoint will be added to the list of NAT
+/// candidates, so other peers have a better chance of connecting.
 pub fn inject_endpoints(session: &Session, peers: &mut Vec<Peer>) {
     for peer in peers {
-        if peer.contents.endpoint.is_none() {
-            if let Some(endpoint) = session.context.endpoints.read().get(&peer.public_key) {
-                peer.contents.endpoint = Some(endpoint.to_owned().into());
+        let endpoints = session.context.endpoints.read();
+        let wg_endpoint = endpoints.get(&peer.public_key);
+
+        if peer.contents.endpoint.is_some() {
+            if let Some(wg_endpoint) = wg_endpoint {
+                // The peer already has an endpoint specified, but it might be stale.
+                // If there is an endpoint reported from wireguard, we should add it
+                // to the list of candidates so others can try to connect using it.
+                peer.contents.candidates.push(wg_endpoint.to_owned().into());
             }
+        } else if let Some(wg_endpoint) = wg_endpoint {
+            peer.contents.endpoint = Some(wg_endpoint.to_owned().into());
         }
     }
 }