The gateway now has a small Linux PacketSocket wrapper for raw Ethernet frame
I/O. It resolves the configured interface with if_nametoindex, opens an
AF_PACKET/SOCK_RAW socket for ETH_P_ALL, binds it to the interface, and exposes
thin send_frame and recv_frame helpers around the owned file descriptor.
The gateway binary opens this socket after completing the relay control
handshake. The frame bridge loop is still intentionally left for a later slice,
but the process now proves the two required resources are available: relay
admission and raw L2 access on the LAN interface.
Tests cover interface-name validation and missing-interface lookup without
requiring root or CAP_NET_RAW.
Test Plan:
- cargo fmt --check
- cargo test --workspace
- cargo clippy --workspace --all-targets -- -D warnings
Refs: PLAN.md Linux AF_PACKET gateway socket
The gateway binary now has a real relay-facing configuration and QUIC control
handshake. It accepts a relay socket address, expected TLS server name, pinned
DER relay certificate, room code, LAN interface name, and advertised datagram
budget, then connects as role = gateway and waits for a welcome response.
The ALPN token moved into lanparty-ctrl so relay and gateway share the same
protocol identifier instead of carrying duplicate private constants. The gateway
still stops after the control-plane connection; AF_PACKET capture and injection
remain a later slice.
The connector test spins up a local Quinn server with a self-signed certificate,
trusts that certificate explicitly, verifies the outgoing gateway hello, and
checks the received welcome metadata.
Test Plan:
- cargo fmt --check
- cargo test --workspace
- cargo clippy --workspace --all-targets -- -D warnings
Refs: PLAN.md Linux gateway outbound relay connection
ddidderr
