feat: prune old, inactive paths

iroh/src/magicsock/remote_map.rs

@@ -235,11 +235,6 @@ pub enum Source {
         _0: Private,
     },
     /// We established a connection on this address.
-    ///
-    /// Currently this means the path was in uses as [`PathId::ZERO`] when the a connection
-    /// was added to the `RemoteStateActor`.
-    ///
-    /// [`PathId::ZERO`]: quinn_proto::PathId::ZERO
     #[strum(serialize = "Connection")]
     Connection {
         /// private marker

iroh/src/magicsock/remote_map/remote_state.rs

@@ -44,16 +44,6 @@ use crate::{
 mod guarded_channel;
 mod path_state;
 
-// TODO: use this
-// /// Number of addresses that are not active that we keep around per endpoint.
-// ///
-// /// See [`RemoteState::prune_direct_addresses`].
-// pub(super) const MAX_INACTIVE_DIRECT_ADDRESSES: usize = 20;
-
-// TODO: use this
-// /// How long since an endpoint path was last alive before it might be pruned.
-// const LAST_ALIVE_PRUNE_DURATION: Duration = Duration::from_secs(120);
-
 // TODO: use this
 // /// The latency at or under which we don't try to upgrade to a better path.
 // const GOOD_ENOUGH_LATENCY: Duration = Duration::from_millis(5);
@@ -442,6 +432,7 @@ impl RemoteStateActor {
                 self.paths
                     .insert(path_remote, Source::Connection { _0: Private });
                 self.select_path();
+                self.prune_ip_paths();
 
                 if path_remote_is_ip {
                     // We may have raced this with a relay address.  Try and add any
@@ -492,6 +483,9 @@ impl RemoteStateActor {
             self.send_disco_message(dst, disco::Message::Ping(ping))
                 .await;
         }
+        // prune any unused/inactive paths, now that we have added potential
+        // new ones
+        self.prune_ip_paths()
     }
 
     /// Handles [`RemoteStateMessage::PingReceived`].
@@ -525,6 +519,7 @@ impl RemoteStateActor {
 
         trace!("ping received, triggering holepunching");
         self.trigger_holepunching().await;
+        self.prune_ip_paths();
     }
 
     /// Handles [`RemoteStateMessage::PongReceived`].
@@ -537,7 +532,8 @@ impl RemoteStateActor {
                 ?src,
                 txn = ?pong.tx_id,
             );
-
+            // mark that this path has been holepunched
+            self.paths.holepunched(&src);
             self.open_path(&src);
         }
     }
@@ -891,10 +887,12 @@ impl RemoteStateActor {
                     );
                     conn_state.add_open_path(path_remote.clone(), path_id);
                     self.paths
-                        .insert(path_remote, Source::Connection { _0: Private });
+                        .insert(path_remote.clone(), Source::Connection { _0: Private });
+                    self.paths.holepunched(&path_remote);
                 }
 
                 self.select_path();
+                self.prune_ip_paths();
             }
             PathEvent::Abandoned { id, path_stats } => {
                 trace!(?path_stats, "path abandoned");
@@ -1046,6 +1044,20 @@ impl RemoteStateActor {
             }
         }
     }
+
+    /// TODO: fix up docs once review indicates this is actually
+    /// the criteria for pruning.
+    fn prune_ip_paths(&mut self) {
+        let open_paths = self
+            .connections
+            .values()
+            .flat_map(|state| state.open_paths.values());
+        self.paths.prune_ip_paths(
+            &self.pending_open_paths,
+            &self.selected_path.get(),
+            open_paths,
+        );
+    }
 }
 
 /// Messages to send to the [`RemoteStateActor`].