When a WireGuard tunnel handshake timed out or a rekey failed,
Inner::on_tunnel_failed closed the transport link and reported the failure
to the agent core. However:
1. The peer remained in WireguardDevice::inner.peers. Once boringtun
declared ConnectionExpired (after 90s), self.tunn.is_expired() remained
permanently true on all subsequent 250ms timer ticks. drive_timers
repeatedly detected failed = true every 250ms, flooding logs with
'WARN WireGuard tunnel failed due to rekey timeout, triggering fallback'
and sending repeated protocol failure events to the core 4 times/sec.
2. In WireguardLink::send, is_handshake_init incorrectly expected an
envelope header offset (msg[74] == 1) when checking for initiation
packets, which failed on raw WireGuard UDP packets. As a result,
handshake initiations were not broadcast to all candidate endpoints.
3. In WireguardTransport::accept_loop, packet source matching contained
dead envelope destination matching inspecting ephemeral key bytes
against local endpoint IDs.
Fixes:
- In crates/tsunagi-wireguard/src/device.rs:
- Add failed: bool to FlowTunnel to latch failure state. Once a failure
is reported, update_timers returns (TunnResult::Done, false) on all
subsequent ticks until a new handshake is started or completed.
- In Inner::on_tunnel_failed, remove the failed peer from inner.peers so
drive_timers ceases ticking on the dead tunnel.
- In crates/tsunagi-wireguard/src/plugin.rs:
- In Worker::sync, retain only active unclosed links in state.links.
- In crates/tsunagi-wireguard/src/transport.rs:
- Check is_handshake_init directly as '!msg.is_empty() && msg[0] == 1',
ensuring handshake initiations are broadcast to all candidate addresses.
- Clean up matched_peer to look up links and peer candidate addresses directly.
- Tests:
- Update test_flow_tunnel_rekey_timeout_triggers_failure to assert failure
latching and verify no repeated failure reports on subsequent ticks.
Validation on Linux:
- cargo fmt --all -- --check passed.
- cargo clippy --locked --workspace --all-targets -- -D warnings passed.
- cargo test --locked --workspace --all-targets passed.
- cargo build --release passed.
Aleksandr Bogomiakov
d2778f0b5a