QUIC announced addresses are silently dropped by the private-address filter

Environment

fnn built from PR #1644 head 478f146286b5c07a9f7ac27ac94d43e5bc79e6ab (fnn Fiber v0.9.0 (478f146 2026-09-02)), release build, Linux x86_64 Node has a public IPv4 address; config contains both TCP and QUIC announced addresses Config (relevant part)

fiber: listening_addr: "/ip4/0.0.0.0/tcp/8999" listening_addrs: - "/ip4/0.0.0.0/udp/8999/quic-v1" announce_listening_addr: true announced_addrs: - "/ip4/<PUBLIC_IP>/tcp/8999" - "/ip4/<PUBLIC_IP>/udp/8999/quic-v1" Expected node_info.addresses contains both public addresses, including /ip4/<PUBLIC_IP>/udp/8999/quic-v1/p2p/, and the QUIC address is propagated to other nodes via NodeAnnouncement gossip.

Actual node_info.addresses only contains the TCP address. The QUIC announced address is silently dropped and therefore never gossiped. The UDP/QUIC listener itself works (visible in ss -lunp), only announcement is affected.

Root cause In crates/fiber-lib/src/fiber/network.rs, announced addresses are filtered unless announce_private_addr is set:

if !config.announce_private_addr.unwrap_or_default() { announced_addrs.retain(crate::utils::is_addr_reachable); } is_addr_reachable (crates/fiber-lib/src/utils/mod.rs) handles DNS and onion addresses specially, but for IP-based addresses it delegates to tentacle's multiaddr_to_socketaddr (tentacle 0.7.7, src/utils.rs:97), which only matches /ip4|ip6/tcp/... tuples. For a QUIC multiaddr (/ip4//udp//quic-v1[/p2p/]) it returns None, so unwrap_or_default() makes the address count as unreachable and it is removed — even when the IP is public.

Impact

Public QUIC addresses configured in announced_addrs never appear in node_info.addresses and are never announced to the network, so third-party nodes cannot discover a node's QUIC address via gossip (breaks the discovery scenario the PR intends to support). Direct dialing via an explicit QUIC multiaddr in connect_peer is unaffected. Workaround Set announce_private_addr: true to skip the reachability filter (side effect: 0.0.0.0 listen addresses are also announced).

Suggested fix Make the reachability check transport-aware, e.g. in is_addr_reachable also extract the socket address for Udp protocols (or use tentacle::utils::find_type / TransportType::QuicV1 to recognize QUIC multiaddrs and check the IP part with is_reachable regardless of transport).

Evidence

Without workaround: node_info.addresses = only /ip4/<PUBLIC_IP>/tcp/8999/p2p/QmU7dJ4... With announce_private_addr: true: addresses include /ip4/<PUBLIC_IP>/udp/8999/quic-v1/p2p/QmU7dJ4... Verified during public-network acceptance testing between two AWS hosts (test02/test05).