Sessions in the Established state that have no activity for 90 seconds
are now automatically removed. This ensures idle sessions are torn down
before transit node coord_cache entries expire (300s TTL), so that when
traffic resumes a fresh SessionSetup re-warms transit node caches with
current coordinates.
The identity cache now stores registration timestamps and expires
entries after 60 seconds via lazy expiry on lookup. This prevents
unbounded growth while allowing natural repopulation through DNS
resolution on next use.
Timer ordering: identity (60s) < session (90s) < coord_cache (300s).
Both timeouts are configurable: node.session.idle_timeout_secs and
node.cache.identity_ttl_secs. Setting idle_timeout_secs to 0 disables
session idle purging.
Changes:
- Add idle_timeout_secs (default 90) to SessionConfig
- Add identity_ttl_secs (default 60) to CacheConfig
- Add timestamp to identity_cache entries, lazy expiry on lookup
- Add purge_idle_sessions() called from tick loop
- Remove #[cfg(test)] from SessionEntry::last_activity()
- 7 new tests covering timeout behavior and edge cases
Wire the discovery protocol into the data plane path so that
find_next_hop() consults route_cache as a fallback when coord_cache
has no entry. When session initiation fails due to missing routes,
trigger discovery (initiate_lookup) instead of immediately sending
ICMPv6 Destination Unreachable. On discovery completion, retry
session initiation for any pending TUN packets.
Changes:
- find_next_hop() falls back to route_cache when coord_cache misses
- handle_tun_outbound() triggers discovery on session failure
- handle_lookup_response() retries session after discovery completes
- handle_coords_required() triggers discovery for missing coordinates
- Add pending_lookups deduplication with 10-second timeout
- Periodic cleanup of stale lookups in tick handler
- New test: route_cache fallback verification in find_next_hop
Add DNS responder that resolves <npub>.fips queries to FipsAddress IPv6
addresses. Resolution is pure computation (npub → NodeAddr → IPv6) with
identity cache priming as a side effect, enabling subsequent TUN packet
routing to non-peer destinations.
- New dns.rs module: resolve_fips_query(), handle_dns_packet() using
simple-dns crate, run_dns_responder() async UDP server loop
- DnsConfig in config.rs: enabled, bind_addr (127.0.0.1), port (5354)
- Fourth select! arm in RX event loop for DNS identity channel
- DNS task spawn/abort in node lifecycle
- 10 new tests (420 total)
Add examples/two-node-udp/ with standalone walkthrough for testing two
FIPS nodes in Linux network namespaces over a veth pair. Includes
network diagram, config files, DNS routing setup, and troubleshooting.
Wire the TUN reader to the session layer for end-to-end IPv6 packet
delivery through the mesh. TUN reader forwards FIPS-destined packets
(fd::/8) to Node via tokio::sync::mpsc channel. Identity cache maps
FipsAddress prefix bytes to NodeAddr + PublicKey for reverse address
resolution, populated at peer promotion and session creation. Outbound
handler validates IPv6, looks up destination identity, routes through
established session or initiates new one with pending packet queue
(16/dest, 256 dests max). Queue flushed on session establishment.
ICMPv6 Destination Unreachable for unknown destinations. 6 new tests
including 3-node forwarded TUN data and pending queue flush. 410 tests
pass, clean build.
Split handlers.rs (986 lines) into handlers/ with 5 subfiles organized
by responsibility: rx_loop, encrypted, handshake, dispatch, timeout.
Split tests.rs (2350 lines) into tests/ with 4 subfiles: unit tests,
handshake integration, spanning tree convergence, and bloom filter tests.
Shared test helpers extracted to tests/mod.rs.
Visibility adjusted from pub(super) to pub(in crate::node) for handler
methods now two levels deep. Unused imports cleaned up in node/mod.rs.
All 316 tests pass, zero warnings.
Johnathan Corgan