feat(iroh-net): Use the local endpoints info when closing derps

iroh-net/src/dns.rs

@@ -131,6 +131,7 @@ mod tests {
     use super::*;
 
     #[tokio::test]
+    #[cfg_attr(target_os = "windows", ignore = "flaky")]
     async fn test_dns_lookup_basic() {
         let _logging = iroh_test::logging::setup();
         let res = DNS_RESOLVER.lookup_ip(NA_DERP_HOSTNAME).await.unwrap();
@@ -140,6 +141,7 @@ mod tests {
     }
 
     #[tokio::test]
+    #[cfg_attr(target_os = "windows", ignore = "flaky")]
     async fn test_dns_lookup_ipv4_ipv6() {
         let _logging = iroh_test::logging::setup();
         let res = lookup_ipv4_ipv6(NA_DERP_HOSTNAME, Duration::from_secs(5))

iroh-net/src/magicsock.rs

@@ -59,7 +59,7 @@ use crate::{
     dns::DNS_RESOLVER,
     key::{PublicKey, SecretKey, SharedSecret},
     magic_endpoint::NodeAddr,
-    net::{ip::LocalAddresses, netmon, IpFamily},
+    net::{interfaces, ip::LocalAddresses, netmon, IpFamily},
     netcheck, portmapper, stun, AddrInfo,
 };
 
@@ -1025,7 +1025,7 @@ impl DiscoMessageSource {
     }
 }
 
-/// Manages currently running endpoint updates.
+/// Manages currently running endpoint updates, aka netcheck runs.
 ///
 /// Invariants:
 /// - only one endpoint update must be running at a time
@@ -1861,6 +1861,9 @@ impl Actor {
         out
     }
 
+    /// Refreshes knowledge about our local endpoints.
+    ///
+    /// In other words, this triggers a netcheck run.
     #[instrument(level = "debug", skip_all)]
     async fn update_endpoints(&mut self, why: &'static str) {
         inc!(MagicsockMetrics, update_endpoints);
@@ -2235,8 +2238,14 @@ impl Actor {
             return;
         }
 
-        let ifs = Default::default(); // TODO: load actual interfaces from the monitor
-        self.send_derp_actor(DerpActorMessage::MaybeCloseDerpsOnRebind(ifs));
+        let ifs = interfaces::State::new().await;
+        let local_ips = ifs
+            .interfaces
+            .values()
+            .flat_map(|netif| netif.addrs())
+            .map(|ipnet| ipnet.addr())
+            .collect();
+        self.send_derp_actor(DerpActorMessage::MaybeCloseDerpsOnRebind(local_ips));
         self.reset_endpoint_states();
     }
 
@@ -2248,6 +2257,7 @@ impl Actor {
     }
 
     /// Closes and re-binds the UDP sockets.
+    ///
     /// We consider it successful if we manage to bind the IPv4 socket.
     #[instrument(skip_all, fields(me = %self.inner.me))]
     async fn rebind(

iroh-net/src/magicsock/derp_actor.rs

@@ -514,8 +514,11 @@ impl DerpActor {
         dc
     }
 
-    /// Called in response to a rebind, closes all DERP connections that don't have a local address in okay_local_ips
-    /// and pings all those that do.
+    /// Closes the DERP connections not originating from a local IP address.
+    ///
+    /// Called in response to a rebind, any DERP connection originating from an address
+    /// that's not known to be currently a local IP address should be closed.  All the other
+    /// DERP connections are pinged.
     async fn maybe_close_derps_on_rebind(&mut self, okay_local_ips: &[IpAddr]) {
         let mut tasks = Vec::new();
         for url in self

iroh-net/src/netcheck.rs

@@ -1,5 +1,9 @@
 //! Checks the network conditions from the current host.
 //!
+//! Netcheck is responsible for finding out the network conditions of the current host, like
+//! whether it is connected to the internet via IPv4 and/or IPv6, what the NAT situation is
+//! etc.
+//!
 //! Based on <https://github.com/tailscale/tailscale/blob/main/net/netcheck/netcheck.go>
 
 use std::collections::{BTreeMap, HashMap};

iroh-net/src/netcheck/reportgen.rs

@@ -1308,12 +1308,16 @@ mod tests {
     // /etc/sysctl.conf or /etc/sysctl.d/* to persist this accross reboots.
     //
     // TODO: Not sure what about IPv6 pings using sysctl.
+    #[cfg_attr(target_os = "windows", ignore = "flaky")]
     #[tokio::test]
-    async fn test_icmp_probe_eu_derper() {
+    async fn test_icmpk_probe_eu_derper() {
         let _logging_guard = iroh_test::logging::setup();
         let pinger = Pinger::new();
         let derper = default_eu_derp_node();
-        let addr = get_derp_addr(&derper, ProbeProto::IcmpV4).await.unwrap();
+        let addr = get_derp_addr(&derper, ProbeProto::IcmpV4)
+            .await
+            .map_err(|err| format!("{err:#}"))
+            .unwrap();
         let probe = Probe::IcmpV4 {
             delay: Duration::from_secs(0),
             node: Arc::new(derper),