Commit Graph
3 Commits
Author SHA1 Message Date
Aleksandr Bogomiakov d2778f0b5a Prevent WireGuard timer loop failure spam and fix handshake broadcast
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.
2026-10-01 03:18:32 +01:00
Aleksandr Bogomiakov 3930dff2dc Detect WireGuard tunnel rekey failure and trigger automatic fallback
Previously, because UDP is connectionless, when a pure WireGuard tunnel
encountered handshake or rekey failures (e.g. boringtun logging
`WARN HANDSHAKE(REKEY_TIMEOUT)` and `CONNECTION_EXPIRED`), the
`WireguardLink` never closed. It remained active in `agent.links` and
as a direct hop in `RelayHub.raw`. Consequently, outgoing packets
continued to be blackholed over the dead direct path, preventing
`RelayHub` from using working multihop relay routes and preventing
the agent from falling back to alternative protocols (`tcp-tls` or
`wg-quic`).

Key changes:
- In `crates/tsunagi-wireguard/src/device.rs`:
  - In `FlowTunnel`, track active handshake and rekey attempts via
    `handshake_started_at`. If an active handshake attempt remains
    unanswered beyond `HANDSHAKE_TIMEOUT` (15s) or boringtun reports
    `ConnectionExpired`, declare the tunnel dead.
  - Reset timeout timers upon successful handshake reception in
    `decapsulate`.
  - In `drive_timers`, when tunnel failure is detected, trigger
    `inner.on_tunnel_failed(peer)`, which closes the direct transport
    link and notifies the agent via `PluginContext::report_peer_protocol_failure`.
- In `crates/tsunagi-wireguard/src/transport.rs`:
  - Add `WireguardLink::close` to transition `is_closed` to true and
    notify `closed_notify`.
  - In `WireguardLink::recv`, select on `closed_notify` so readers
    unblock and return `None` immediately on close.
  - Add `WireguardTransport::close_link` to close active links by
    network and peer.
- In `crates/tsunagi/src/dataplane/mod.rs`:
  - Add `PluginRequest::ProtocolFailure` and public helper
    `PluginContext::report_peer_protocol_failure`.
- In `crates/tsunagi/src/agent/mod.rs` and `crates/tsunagi/src/agent/network.rs`:
  - Add `NetCommand::ProtocolFailure` to runtime command handling.
  - On protocol failure: remove dead direct link from `self.links`,
    clear it from `RelayHub.raw` (so `RelayHub` immediately routes
    over available multihop relays), record failure on `wg` for that
    peer with exponential backoff cooldown, emit `DataLinkDown`, and
    immediately call `ensure_links()` to dial the next mutually supported
    protocol (`tcp-tls` or `wg-quic`).
- Tests:
  - Add `test_flow_tunnel_rekey_timeout_triggers_failure` and
    `test_flow_tunnel_reset_on_handshake` unit tests in `device.rs`.
  - Add `test_wireguard_link_close_and_transport_close_link` in
    `transport_tests.rs`.
  - Add `test_protocol_dial_state_cooldown_and_fallback_selection` in
    `network.rs`.

Validation on Linux:
- cargo fmt --all -- --check passed.
- cargo clippy --locked --workspace --all-targets -- -D warnings passed.
- cargo test --locked --workspace --all-targets passed (350+ tests passed).
- Built release binary: target/release/tsunagi.
2026-10-01 03:02:09 +01:00
Aleksandr Bogomiakov 7070a16104 Add pure WireGuard direct UDP data plane plugin and transport
Peers communicating on uncensored networks can benefit from raw WireGuard
performance over direct UDP without QUIC framing or double-encryption
overhead. This provides Tailscale-like direct tunnel performance while
preserving Tsunagi's decentralized mesh architecture.

Key changes:
- Create `tsunagi-wireguard` crate implementing the `IpPlugin` and
  `PacketTransport` contracts:
  - `WG_PROTOCOL = "wg"` with wire version 1.
  - Bounded `WgAnnouncement` carrying WireGuard public keys, listening UDP
    ports, and candidate IP addresses (filtering out overlay interfaces).
  - `WgKeyStore` managing persistent per-network WireGuard X25519 keys
    in SQLite with zeroization on drop.
  - `WireguardTransport` providing direct UDP packet transmission, candidate
    address tracking, inbound link delivery, and roaming support.
  - `WireguardDevice` running userspace WireGuard encryption via `boringtun`,
    timer maintenance, and AllowedIPs source enforcement.
- Integrate `wg` into `tsunagi-cli`:
  - Set default protocols to `"wg,tcp-tls,wg-quic"` so all protocols are
    enabled by default in order of throughput and performance.
  - Support `"wireguard"` as a convenience alias for `"wg"` in `--protocol`.
  - Bind `PureWgTransport` and launch the inbound datagram accept loop on `up`.
  - Pass `pure_wg` plugin to `AgentControl` and update `build_report` so
    active WireGuard tunnels and overlay metrics are reported in `tsunagi status`.
  - Clean up WireGuard keys on network removal in `forget_protocol_state`.
- Comprehensive test coverage in `tsunagi-wireguard`:
  - `announcement_tests`: round-trip serialization and verification of malformed,
    mismatched network, zero port, or self-claiming announcements.
  - `transport_tests`: loopback UDP link delivery between transports.
  - `plugin_tests`: end-to-end two-peer handshake and bidirectional IP packet
    transit over direct UDP.

Validation on Linux:
- cargo fmt --all -- --check passed.
- cargo clippy --locked --workspace --all-targets -- -D warnings passed.
- cargo test --locked --workspace --all-targets passed.
2026-10-01 01:24:25 +01:00