Commit Graph
3 Commits
Author SHA1 Message Date
Aleksandr Bogomiakov 533921059a Install broadcast route and firewall allowance on the host while broadcast is on
LAN discovery (CS 1.6 and similar) only worked after two manual steps on every
host: route 255.255.255.255 through the TUN, and allow inbound traffic on it.
Without the route the game's limited broadcast leaves via the physical adapter
and never reaches the overlay; without the firewall allowance the server's
unicast reply (from a different address than the one the request went to, so
never matched by conntrack) is dropped before the game's socket. Verified by
hand on Linux: with both in place the server answered A2S_INFO over the overlay.

The system level (not a plugin) now installs exactly those two things for the
interface it owns, and removes them when broadcast is turned off, the network
is left or stopped, or the agent exits.

Design:
- New boundary overlay::hostrules (BroadcastHostRules: idempotent apply/clear,
  with Linux, Windows, Mock and Unsupported implementations). TunFactory gains
  host_rules(); ManagedTunFactory::with_host_rules wires it in the CLI.
- Interface::sync_broadcast_rules reconciles the host against the routing
  table (RoutingTable::broadcast_host_target) and is called after address sync,
  on live `network broadcast on/off`, on network deactivation and by remove().
  Failure is contained: the outcome is kept and logged, never fatal.
- One interface carries several networks but the host has one 255.255.255.255
  route, so the source is the lowest NetworkId among broadcast-enabled networks
  with an address (documented in docs/broadcast.md).
- Linux: the route is added on the existing netlink thread (preferred source =
  overlay address, replace semantics). The firewall rule is `iptables -I INPUT
  -i <if> -p udp -s <overlay range>` tagged with a comment `tsunagi:<if>`;
  it is UDP-only and range-limited on purpose so TCP services stay unexposed.
  iptables is located in fixed system directories, never via PATH; stale tagged
  rules (e.g. from a crash) are replaced. A missing iptables leaves the route in
  place and is reported. rp_filter is not touched.
- Windows: PowerShell (absolute path) New-NetRoute metric 1 and a tagged
  inbound UDP Defender rule scoped to the interface alias and overlay range.
- status shows a `broadcast rules` row (ok, or which half failed and why).
  IPC control protocol bumped 14 -> 15 because OverlayReport gained a field.
- AGENTS.md records the narrow exception to "never touch routing/firewall".

Compatibility: restart the agent after upgrading (control protocol 15). No wire
or schema change.

Checks run (Linux only): cargo fmt --check, cargo clippy --locked --workspace
--all-targets -D warnings, cargo test --locked --workspace --all-targets, all
passing. Tests use a mock host and a scripted iptables; no OS setting is
changed. NOT done: the Windows code was never compiled for or run on Windows
(cross-compiling failed for lack of a C toolchain), only its script building is
unit-tested; the real netlink route and iptables calls were not exercised
against a live kernel in the suite; CS 1.6 was not launched from this change.
2026-10-01 15:03:43 +01:00
ab db9015b26c Allow network commands to select stored names
Leaving a configured network required copying its opaque id even when its
name identified exactly one saved network. Resolve exact, case-sensitive
names from the existing local state alongside full ids and unique id prefixes.
Use the shared resolver for leave, stop, start, secret and broadcast so the
same selector has the same meaning throughout the CLI. IPC and storage still
operate on the resolved id; release and offline-removal behavior are unchanged.

Refuse ambiguous names and name/id-prefix collisions before any mutation,
listing matching names and full ids without secrets. Full ids take precedence
to provide a definitive escape from ambiguity. Preserve copied id ellipses
without stripping literal ellipses from network names.

Update help and examples. Make administrator-friendly, predictable CLI behavior
a core requirement in AGENTS.md, including actionable errors and no guessing
which resource a destructive command should affect.

Validation on Windows: cargo fmt --all -- --check and workspace/all-target
Clippy with -D warnings passed. Release workspace/all-target tests: 318 passed,
including real-process online/offline leave-by-name, preservation of other
networks, ambiguous/unknown selectors, and consistent name selection across
commands. Two existing Windows SQLite wipe failures were explicitly skipped
(a_wipe_removes_everything_and_the_next_start_is_a_stranger and
wiping_twice_is_as_ordinary_as_wiping_once). The public-DHT smoke test and
forwarding benchmark remain ignored by default. Tests use isolated state;
the user's running agent and configured networks were not changed.
2026-09-22 19:00:08 +03:00
ab c724981bfd Added per-network LAN broadcast relay
LAN game discovery previously dropped IPv4 broadcasts at TUN ingress. Carry
limited and subnet-directed UDP broadcasts to authenticated, opted-in members
of the source network, including destinations reached through mesh relays.
Preserve the original IP/UDP bytes and deliver received broadcasts only to the
local TUN; never reflood them or expose another pair's plaintext at transit.

Build immutable recipient snapshots on address and participation changes. The
origin sends one ordinary end-to-end encrypted copy per recipient; the existing
fast, bounded-hop transport router remains unchanged. Validate UDP framing,
source ownership and destination admission without game-specific port rules.
Keep network domains isolated and refuse implicit gateways to physical LANs.
The separate broadcast policy/domain layer is the extension point for future
authorized subnet exports; physical capture, bridging and LAN deduplication
are deliberately not implemented yet.

Persist default-on participation independently for each local network. Add
join --no-broadcast/--broadcast and network broadcast <id> [on|off], including
live updates and authenticated announcements. Joining without a flag preserves
the saved choice. Opt-out stops local origination and delivery, while opaque
unicast transit for other members keeps working.

Migrate SQLite schema 3 to 4 without replacing identities or signed state.
Use control ALPN 3 and local IPC protocol 14 for the new announcement/request
shapes; update peers and restart running agents together. The data ALPN 4
envelope remains unchanged. No release version bump, tag or push is included.

Document agent-owned commits in AGENTS.md: short English subjects, explanatory
bodies, scoped staging, honest validation, and repository-local fallback author
AB <ab@hexor.cy> only when an effective name/email is missing. Release actions
remain the user's responsibility.

Validation on Windows: cargo fmt --all -- --check; cargo check --locked
--workspace --all-targets; cargo clippy --locked --workspace --all-targets --
-D warnings; release workspace/all-target tests: 313 passed. The two existing
SQLite wipe failures (a_wipe_removes_everything_and_the_next_start_is_a_stranger
and wiping_twice_is_as_ordinary_as_wiping_once) were explicitly skipped; the
public-DHT smoke test and forwarding benchmark remain ignored by default.
New coverage exercises real iroh/WireGuard multihop fanout, single delivery,
runtime opt-out, unicast replies, domain isolation, malformed input and schema
migration. TUNs are in-memory; actual games and OS adapter selection were not
tested.
2026-09-22 18:33:52 +03:00