mDNS behaviour sends non-listening LAN address

[b-zee]

Summary

When a node listens on localhost, mDNS behaviour will still broadcast the LAN address of the machine.

This means that peers will receive unreachable addresses. E.g. if a peer dials the Discovered address, the peer will not respond because it's only listening on localhost.

Expected behavior

Broadcast only listening addresses.

Actual behavior

A non-listening address is sent out.

Relevant log output

# Node A
2025-01-21T11:39:06.711691Z  INFO test: Local peer ID local_peer=12D3KooWS5B2X8mQwHCtiBmMQbjsHA84rUYsC6psZtd3NoZ9d6CG
2025-01-21T11:39:06.713897Z TRACE test::root_behaviour: on_swarm_event NewListener(NewListener { listener_id: ListenerId(1) })
2025-01-21T11:39:06.714204Z TRACE test::behaviour: NewListenAddr listener_id=1 address=/ip4/127.0.0.1/udp/58127/quic-v1
2025-01-21T11:39:14.231332Z  WARN test::behaviour: mDNS: Discovered([(PeerId("12D3KooWMcc2CwohBjwgBoegKXYuAGHaSZMDxCm5tRZ4gn9fbu1n"), /ip4/192.168.1.105/udp/37009/quic-v1/p2p/12D3KooWMcc2CwohBjwgBoegKXYuAGHaSZMDxCm5tRZ4gn9fbu1n)])
2025-01-21T11:39:14.231496Z TRACE test::behaviour: NewExternalAddrOfPeer peer=gn9fbu1n address=/ip4/192.168.1.105/udp/37009/quic-v1/p2p/12D3KooWMcc2CwohBjwgBoegKXYuAGHaSZMDxCm5tRZ4gn9fbu1n

# Node B
2025-01-21T11:39:14.226528Z  INFO test: Local peer ID local_peer=12D3KooWMcc2CwohBjwgBoegKXYuAGHaSZMDxCm5tRZ4gn9fbu1n
2025-01-21T11:39:14.229204Z TRACE test::root_behaviour: on_swarm_event NewListener(NewListener { listener_id: ListenerId(1) })
2025-01-21T11:39:14.229542Z TRACE test::behaviour: NewListenAddr listener_id=1 address=/ip4/127.0.0.1/udp/37009/quic-v1
2025-01-21T11:39:14.231227Z  WARN test::behaviour: Unhandled mDNS: Discovered([(PeerId("12D3KooWS5B2X8mQwHCtiBmMQbjsHA84rUYsC6psZtd3NoZ9d6CG"), /ip4/192.168.1.105/udp/58127/quic-v1/p2p/12D3KooWS5B2X8mQwHCtiBmMQbjsHA84rUYsC6psZtd3NoZ9d6CG)])
2025-01-21T11:39:14.231297Z TRACE test::behaviour: NewExternalAddrOfPeer peer=NoZ9d6CG address=/ip4/192.168.1.105/udp/58127/quic-v1/p2p/12D3KooWS5B2X8mQwHCtiBmMQbjsHA84rUYsC6psZtd3NoZ9d6CG

Possible Solution

No response

Version

0.55.0

Would you like to work on fixing this bug?

Yes

[b-zee]

Within scope of #5790.