feat(swarm): allow behaviours to share addresses of peers

Resolves: #4302.

Pull-Request: #4371.

Author: StemCll

Cargo.lock

@@ -83,7 +83,7 @@ libp2p-dcutr = { version = "0.11.0", path = "protocols/dcutr" }
 libp2p-dns = { version = "0.41.1", path = "transports/dns" }
 libp2p-floodsub = { version = "0.44.0", path = "protocols/floodsub" }
 libp2p-gossipsub = { version = "0.46.1", path = "protocols/gossipsub" }
-libp2p-identify = { version = "0.44.1", path = "protocols/identify" }
+libp2p-identify = { version = "0.44.2", path = "protocols/identify" }
 libp2p-identity = { version = "0.2.8" }
 libp2p-kad = { version = "0.46.0", path = "protocols/kad" }
 libp2p-mdns = { version = "0.45.1", path = "protocols/mdns" }
@@ -99,11 +99,11 @@ libp2p-pnet = { version = "0.24.0", path = "transports/pnet" }
 libp2p-quic = { version = "0.10.2", path = "transports/quic" }
 libp2p-relay = { version = "0.17.1", path = "protocols/relay" }
 libp2p-rendezvous = { version = "0.14.0", path = "protocols/rendezvous" }
-libp2p-request-response = { version = "0.26.1", path = "protocols/request-response" }
+libp2p-request-response = { version = "0.26.2", path = "protocols/request-response" }
 libp2p-server = { version = "0.12.5", path = "misc/server" }
 libp2p-stream = { version = "0.1.0-alpha", path = "protocols/stream" }
-libp2p-swarm = { version = "0.44.1", path = "swarm" }
-libp2p-swarm-derive = { version = "=0.34.2", path = "swarm-derive" } # `libp2p-swarm-derive` may not be compatible with different `libp2p-swarm` non-breaking releases. E.g. `libp2p-swarm` might introduce a new enum variant `FromSwarm` (which is `#[non-exhaustive]`) in a non-breaking release. Older versions of `libp2p-swarm-derive` would not forward this enum variant within the `NetworkBehaviour` hierarchy. Thus the version pinning is required.
+libp2p-swarm = { version = "0.44.2", path = "swarm" }
+libp2p-swarm-derive = { version = "=0.34.3", path = "swarm-derive" } # `libp2p-swarm-derive` may not be compatible with different `libp2p-swarm` non-breaking releases. E.g. `libp2p-swarm` might introduce a new enum variant `FromSwarm` (which is `#[non-exhaustive]`) in a non-breaking release. Older versions of `libp2p-swarm-derive` would not forward this enum variant within the `NetworkBehaviour` hierarchy. Thus the version pinning is required.
 libp2p-swarm-test = { version = "0.3.0", path = "swarm-test" }
 libp2p-tcp = { version = "0.41.0", path = "transports/tcp" }
 libp2p-tls = { version = "0.3.0", path = "transports/tls" }

Cargo.toml

@@ -3,8 +3,8 @@ name = "libp2p-autonat"
 edition = "2021"
 rust-version = { workspace = true }
 description = "NAT and firewall detection for libp2p"
-version = "0.12.0"
 authors = ["David Craven <[email protected]>", "Elena Frank <[email protected]>"]
+version = "0.12.0"
 license = "MIT"
 repository = "https://github.com/libp2p/rust-libp2p"
 keywords = ["peer-to-peer", "libp2p", "networking"]

protocols/autonat/Cargo.toml

@@ -268,6 +268,7 @@ impl Behaviour {
     pub fn add_server(&mut self, peer: PeerId, address: Option<Multiaddr>) {
         self.servers.insert(peer);
         if let Some(addr) = address {
+            #[allow(deprecated)]
             self.inner.add_address(&peer, addr);
         }
     }

protocols/autonat/src/behaviour.rs

@@ -203,6 +203,7 @@ async fn wait_for_reservation(
             SwarmEvent::ExternalAddrConfirmed { address } if !is_renewal => {
                 assert_eq!(address, client_addr);
             }
+            SwarmEvent::NewExternalAddrOfPeer { .. } => {}
             e => panic!("{e:?}"),
         }
     }

protocols/dcutr/tests/lib.rs

@@ -1,3 +1,10 @@
+## 0.44.2
+
+- Emit `ToSwarm::NewExternalAddrOfPeer` for all external addresses of remote peers.
+  For this work, the address cache must be enabled via `identify::Config::with_cache_size`.
+  The default is 0, i.e. disabled.
+  See [PR 4371](https://github.com/libp2p/rust-libp2p/pull/4371).
+
 ## 0.44.1
 
 - Ensure `Multiaddr` handled and returned by `Behaviour` are `/p2p` terminated.

protocols/identify/CHANGELOG.md

@@ -3,7 +3,7 @@ name = "libp2p-identify"
 edition = "2021"
 rust-version = { workspace = true }
 description = "Nodes identifcation protocol for libp2p"
-version = "0.44.1"
+version = "0.44.2"
 authors = ["Parity Technologies <[email protected]>"]
 license = "MIT"
 repository = "https://github.com/libp2p/rust-libp2p"

protocols/identify/Cargo.toml

@@ -26,15 +26,14 @@ use libp2p_identity::PublicKey;
 use libp2p_swarm::behaviour::{ConnectionClosed, ConnectionEstablished, DialFailure, FromSwarm};
 use libp2p_swarm::{
     ConnectionDenied, DialError, ExternalAddresses, ListenAddresses, NetworkBehaviour,
-    NotifyHandler, StreamUpgradeError, THandlerInEvent, ToSwarm,
+    NotifyHandler, PeerAddresses, StreamUpgradeError, THandlerInEvent, ToSwarm,
 };
 use libp2p_swarm::{ConnectionId, THandler, THandlerOutEvent};
-use lru::LruCache;
+
 use std::collections::hash_map::Entry;
 use std::num::NonZeroUsize;
 use std::{
     collections::{HashMap, HashSet, VecDeque},
-    iter::FromIterator,
     task::Context,
     task::Poll,
     time::Duration,
@@ -200,9 +199,9 @@ impl Behaviour {
             .or_default()
             .insert(conn, addr);
 
-        if let Some(entry) = self.discovered_peers.get_mut(&peer_id) {
+        if let Some(cache) = self.discovered_peers.0.as_mut() {
             for addr in failed_addresses {
-                entry.remove(addr);
+                cache.remove(&peer_id, addr);
             }
         }
     }
@@ -268,13 +267,23 @@ impl NetworkBehaviour for Behaviour {
                 info.listen_addrs
                     .retain(|addr| multiaddr_matches_peer_id(addr, &peer_id));
 
-                // Replace existing addresses to prevent other peer from filling up our memory.
-                self.discovered_peers
-                    .put(peer_id, info.listen_addrs.iter().cloned());
-
                 let observed = info.observed_addr.clone();
                 self.events
-                    .push_back(ToSwarm::GenerateEvent(Event::Received { peer_id, info }));
+                    .push_back(ToSwarm::GenerateEvent(Event::Received {
+                        peer_id,
+                        info: info.clone(),
+                    }));
+
+                if let Some(ref mut discovered_peers) = self.discovered_peers.0 {
+                    for address in &info.listen_addrs {
+                        if discovered_peers.add(peer_id, address.clone()) {
+                            self.events.push_back(ToSwarm::NewExternalAddrOfPeer {
+                                peer_id,
+                                address: address.clone(),
+                            });
+                        }
+                    }
+                }
 
                 match self.our_observed_addresses.entry(id) {
                     Entry::Vacant(not_yet_observed) => {
@@ -387,11 +396,11 @@ impl NetworkBehaviour for Behaviour {
                 self.our_observed_addresses.remove(&connection_id);
             }
             FromSwarm::DialFailure(DialFailure { peer_id, error, .. }) => {
-                if let Some(entry) = peer_id.and_then(|id| self.discovered_peers.get_mut(&id)) {
-                    if let DialError::Transport(errors) = error {
-                        for (addr, _error) in errors {
-                            entry.remove(addr);
-                        }
+                if let (Some(peer_id), Some(cache), DialError::Transport(errors)) =
+                    (peer_id, self.discovered_peers.0.as_mut(), error)
+                {
+                    for (addr, _error) in errors {
+                        cache.remove(&peer_id, addr);
                     }
                 }
             }
@@ -445,42 +454,23 @@ fn multiaddr_matches_peer_id(addr: &Multiaddr, peer_id: &PeerId) -> bool {
     true
 }
 
-struct PeerCache(Option<LruCache<PeerId, HashSet<Multiaddr>>>);
+struct PeerCache(Option<PeerAddresses>);
 
 impl PeerCache {
     fn disabled() -> Self {
         Self(None)
     }
 
     fn enabled(size: NonZeroUsize) -> Self {
-        Self(Some(LruCache::new(size)))
-    }
-
-    fn get_mut(&mut self, peer: &PeerId) -> Option<&mut HashSet<Multiaddr>> {
-        self.0.as_mut()?.get_mut(peer)
-    }
-
-    fn put(&mut self, peer: PeerId, addresses: impl Iterator<Item = Multiaddr>) {
-        let cache = match self.0.as_mut() {
-            None => return,
-            Some(cache) => cache,
-        };
-
-        let addresses = addresses.filter_map(|a| a.with_p2p(peer).ok());
-        cache.put(peer, HashSet::from_iter(addresses));
+        Self(Some(PeerAddresses::new(size)))
     }
 
     fn get(&mut self, peer: &PeerId) -> Vec<Multiaddr> {
-        let cache = match self.0.as_mut() {
-            None => return Vec::new(),
-            Some(cache) => cache,
-        };
-
-        cache
-            .get(peer)
-            .cloned()
-            .map(Vec::from_iter)
-            .unwrap_or_default()
+        if let Some(cache) = self.0.as_mut() {
+            cache.get(peer).collect()
+        } else {
+            Vec::new()
+        }
     }
 }
 

protocols/identify/src/behaviour.rs

@@ -110,7 +110,7 @@ async fn only_emits_address_candidate_once_per_connection() {
     async_std::task::spawn(swarm2.loop_on_next());
 
     let swarm_events = futures::stream::poll_fn(|cx| swarm1.poll_next_unpin(cx))
-        .take(5)
+        .take(8)
         .collect::<Vec<_>>()
         .await;
 
@@ -156,6 +156,78 @@ async fn only_emits_address_candidate_once_per_connection() {
     );
 }
 
+#[async_std::test]
+async fn emits_unique_listen_addresses() {
+    let _ = tracing_subscriber::fmt()
+        .with_env_filter(EnvFilter::from_default_env())
+        .try_init();
+
+    let mut swarm1 = Swarm::new_ephemeral(|identity| {
+        identify::Behaviour::new(
+            identify::Config::new("a".to_string(), identity.public())
+                .with_agent_version("b".to_string())
+                .with_interval(Duration::from_secs(1))
+                .with_cache_size(10),
+        )
+    });
+    let mut swarm2 = Swarm::new_ephemeral(|identity| {
+        identify::Behaviour::new(
+            identify::Config::new("c".to_string(), identity.public())
+                .with_agent_version("d".to_string()),
+        )
+    });
+
+    let (swarm2_mem_listen_addr, swarm2_tcp_listen_addr) =
+        swarm2.listen().with_memory_addr_external().await;
+    let swarm2_peer_id = *swarm2.local_peer_id();
+    swarm1.connect(&mut swarm2).await;
+
+    async_std::task::spawn(swarm2.loop_on_next());
+
+    let swarm_events = futures::stream::poll_fn(|cx| swarm1.poll_next_unpin(cx))
+        .take(8)
+        .collect::<Vec<_>>()
+        .await;
+
+    let infos = swarm_events
+        .iter()
+        .filter_map(|e| match e {
+            SwarmEvent::Behaviour(identify::Event::Received { info, .. }) => Some(info.clone()),
+            _ => None,
+        })
+        .collect::<Vec<_>>();
+
+    assert!(
+        infos.len() > 1,
+        "should exchange identify payload more than once"
+    );
+
+    let listen_addrs = infos
+        .iter()
+        .map(|i| i.listen_addrs.clone())
+        .collect::<Vec<_>>();
+
+    for addrs in listen_addrs {
+        assert_eq!(addrs.len(), 2);
+        assert!(addrs.contains(&swarm2_mem_listen_addr));
+        assert!(addrs.contains(&swarm2_tcp_listen_addr));
+    }
+
+    let reported_addrs = swarm_events
+        .iter()
+        .filter_map(|e| match e {
+            SwarmEvent::NewExternalAddrOfPeer { peer_id, address } => {
+                Some((*peer_id, address.clone()))
+            }
+            _ => None,
+        })
+        .collect::<Vec<_>>();
+
+    assert_eq!(reported_addrs.len(), 2, "To have two addresses of remote");
+    assert!(reported_addrs.contains(&(swarm2_peer_id, swarm2_mem_listen_addr)));
+    assert!(reported_addrs.contains(&(swarm2_peer_id, swarm2_tcp_listen_addr)));
+}
+
 #[async_std::test]
 async fn identify_push() {
     let _ = tracing_subscriber::fmt()

protocols/identify/tests/smoke.rs

@@ -1,3 +1,8 @@
+## 0.26.2
+
+- Deprecate `Behaviour::add_address` in favor of `Swarm::add_peer_address`.
+  See [PR 4371](https://github.com/libp2p/rust-libp2p/pull/4371).
+
 ## 0.26.1
 
 - Derive `PartialOrd` and `Ord` for `{Out,In}boundRequestId`.

protocols/request-response/CHANGELOG.md

@@ -3,7 +3,7 @@ name = "libp2p-request-response"
 edition = "2021"
 rust-version = { workspace = true }
 description = "Generic Request/Response Protocols"
-version = "0.26.1"
+version = "0.26.2"
 authors = ["Parity Technologies <[email protected]>"]
 license = "MIT"
 repository = "https://github.com/libp2p/rust-libp2p"
@@ -40,7 +40,7 @@ libp2p-yamux = { workspace = true }
 rand = "0.8"
 libp2p-swarm-test = { path = "../../swarm-test" }
 futures_ringbuf = "0.4.0"
-serde = { version = "1.0", features = ["derive"]}
+serde = { version = "1.0", features = ["derive"] }
 tracing-subscriber = { version = "0.3", features = ["env-filter"] }
 
 # Passing arguments to the docsrs builder in order to properly document cfg's.