BLE transport implementation using L2CAP Connection-Oriented Channels
(SeqPacket mode) via the bluer crate, behind cfg(feature = "ble").
Core transport:
- BleTransport<I> generic over BleIo trait (BluerIo prod, MockBleIo test)
- Connection pool with priority eviction (static > discovered, max 7)
- Connect-on-send via connect_inline() matching TCP behavior
- Per-connection receive loops with pool cleanup on disconnect
Discovery and probing:
- Combined scan_probe_loop using select! over scanner events and a
BinaryHeap delay queue with per-entry random jitter (0-5s) to prevent
herd effects when multiple nodes see the same beacon simultaneously
- Pre-handshake pubkey exchange ([0x00][pubkey:32]) for IK identity
- Cross-probe tie-breaker: smaller NodeAddr's outbound wins (same
convention as FMP/FSP rekey dual-initiation)
- Probed peers reported to DiscoveryBuffer; pool fills through normal
node-layer auto-connect -> send_async -> connect_inline path
Beacon management:
- Periodic advertising: 1s burst every 30s (configurable via
beacon_interval_secs / beacon_duration_secs)
- FIPS service UUID for scan filtering
Configuration (all fields optional with defaults):
- adapter, psm, mtu, max_connections, connect_timeout_ms
- advertise, scan, auto_connect, accept_connections
- beacon_interval_secs (30), beacon_duration_secs (1)
Hardware validated with two BLE nodes:
- 2048-byte MTU, ~60-160ms RTT, zero-config auto-connect
- BLE spike tool at testing/ble/ for standalone adapter validation
42 unit tests + 4 node-level integration tests, all CI-compatible
via MockBleIo (no hardware required). tokio test-util added for
time-dependent scan/probe tests.
Add resolve_socket_addr() with IP fast path and tokio::net::lookup_host()
fallback for DNS hostnames. Peer addresses can now use hostnames like
"peer1.example.com:2121" alongside IP addresses.
UDP transport adds a per-transport DNS cache (60s TTL) to avoid
per-packet resolution. TCP resolves at connect time (one-shot).
Update design docs, config examples, and changelog to reflect hostname
support in transport addressing.
The fips-dns.service unit had three issues:
1. Wants=systemd-resolved.service caused systemd to start systemd-resolved
on systems that weren't using it, breaking existing DNS by rewriting
/etc/resolv.conf to the stub resolver at 127.0.0.53.
2. The ExecStart busy-wait loop for fips0 had no timeout, hanging forever
if fips.service failed to create the TUN device.
3. Installers unconditionally enabled fips-dns.service regardless of whether
systemd-resolved was present.
Fix by replacing Wants= with ConditionPathExists=/run/systemd/resolve (skips
cleanly if resolved isn't running), adding Requires=fips.service (won't start
without the daemon), bounding the fips0 wait loop to 30 seconds, and making
the installers conditional on systemd-resolved being active.
Packaging directory structure:
- packaging/common/ — shared config (fips.yaml) used by all formats
- packaging/systemd/ — systemd-specific installer and service units
Systemd packaging includes:
- build-tarball.sh: builds release binaries and creates a self-contained
install tarball with stripped binaries
- fips.service: systemd unit running the daemon with security hardening
- fips-dns.service: oneshot unit configuring resolvectl to route .fips
domain queries to the FIPS DNS shim on 127.0.0.1:5354
- install.sh: deploys binaries to /usr/local/bin, installs systemd units,
creates fips group for non-root control socket access
- uninstall.sh: removes service and binaries, optional --purge for
config and identity key files
- README.install.md: installation and configuration guide
Default config enables UDP (2121), TCP inbound (8443), TUN, and DNS
resolver. Identity is ephemeral by default for privacy; operators can
uncomment persistent: true to maintain a stable npub for static peer
publishing. Ethernet transport is commented out for per-node setup.
Johnathan Corgan