Add a complete example running a strfry Nostr relay exclusively over
the FIPS mesh using the sidecar pattern. Includes Docker Compose
stack, network isolation via iptables, .fips DNS resolution, nak CLI,
build script with cross-compilation support, and documentation.
Also fix the package-openwrt.yml workflow path to match the
openwrt → openwrt-ipk directory rename.
Adds packaging/openwrt/ with everything needed to produce and distribute
FIPS .ipk packages for OpenWrt routers:
- Makefile: OpenWrt feed package definition using rust/host toolchain,
maps OpenWrt ARCH to Rust musl target triples
- build-ipk.sh: local build script using cargo-zigbuild + direct tar
assembly — no OpenWrt SDK or Docker required. Handles macOS BSD tar
(ustar format, resource fork suppression) and portable ar header
generation for cross-platform .ipk creation. Accepts PKG_VERSION
env var override for CI use.
- files/: procd init script, default fips.yaml (persistent identity,
br-lan and wwan interface examples), firewall helper, dnsmasq .fips
forwarding, br_netfilter sysctl, hotplug for fips0, UCI defaults for
first-boot setup, sysupgrade keeplist
- .github/workflows/package-openwrt.yml: CI workflow (ubuntu-latest +
cargo-zigbuild) building aarch64 and x86_64 .ipk packages using
build-ipk.sh; llvm-strip for cross-compiled binaries; triggers on
every push; publishes to GitHub Releases on version tags. MIPS
targets disabled pending portable-atomic crate (32-bit MIPS lacks
native AtomicU64), with nightly/rust-src toolchain steps prepared
for re-enablement.
- .gitignore: add reference/, dist/, *.ipk
Three-job pipeline:
- build: matrix over ubuntu/macos/windows, native cargo build per runner;
macOS and Windows are continue-on-error (best-effort). Uploads Linux
binary as artifact for downstream jobs.
- test: cargo test --all on ubuntu, gated on build succeeding.
- integration: parallel matrix of static-mesh, static-chain, and
chaos-smoke-10; runs only when build + test both pass. Static jobs
use docker compose + ping-test.sh; chaos job runs the stochastic
simulation via chaos.sh.
Docker testing infrastructure:
- Add iperf3 bandwidth testing (10s duration, 8 parallel streams)
- Install iperf3 in container, auto-start as daemon alongside FIPS
- Support --live flag for real-time iperf3 output during tests
- Aggregate [SUM] bandwidth reporting with correct units
Configuration templating system:
- Single node.template.yaml replacing per-node hand-written configs
- Topology definitions in configs/topologies/ (mesh.yaml, chain.yaml)
- generate-configs.sh script for automatic config generation
- Integrated into build.sh for regeneration on build
- Generated configs in generated-configs/ (gitignored)
Ping test improvements:
- Reduce to 1 ping per test for faster execution (~10s vs ~30s)
- Show response times (RTT) for each test
- Add Ctrl+C trap for clean exit
- Reduce convergence wait from 5s to 3s
Session-layer encryption used an implicit nonce counter with no counter
on the wire, requiring packets to arrive in exact order. Under bulk
transfer load (e.g., SCP), UDP packet loss or reordering permanently
desynchronized sender/receiver counters, causing all subsequent
decryption to fail with no recovery.
Add an 8-byte counter field to the DataPacket wire format and switch
from implicit-counter decrypt() to decrypt_with_replay_check() which
uses the explicit wire counter plus a 2048-packet sliding replay
window — the same pattern already used at the link layer.
Wire format: msg_type(1) + flags(1) + counter(8) + payload_len(2) = 12
bytes (was 4). FIPS_OVERHEAD updated 127 → 135 bytes accordingly.
Add dual-approach MTU handling to prevent TCP connections from hanging
when packets exceed the transport MTU after FIPS encapsulation.
ICMPv6 Packet Too Big:
- Generate RFC 4443 PTB messages for oversized packets at TUN outbound
- Inject back via TUN for local delivery to the application
- Per-source rate limiting (100ms interval, 10s entry expiry)
- MTU check in handle_tun_outbound before session encapsulation
TCP MSS Clamping:
- Intercept SYN packets in run_tun_reader() (outbound)
- Intercept SYN-ACK packets in TunWriter (inbound)
- Clamp MSS option to fit within effective MTU (transport - 127 overhead)
- Recalculate TCP checksum after modification
Code organization:
- ICMP, TCP MSS, and rate limiter modules in upper/ alongside existing
protocol-specific packet handling (dns.rs, tun.rs)
- Shared FIPS_OVERHEAD constant (127 bytes) and effective_ipv6_mtu()
function in upper/icmp.rs
- Node::effective_ipv6_mtu() delegates to the shared function
- run_tun_reader() accepts actual transport MTU from config
Example config corrections:
- UDP transport MTU set to 1472 across all configs (correct max UDP
payload for standard Ethernet: 1500 - 20 IPv4 - 8 UDP)
- Startup logging of effective MTU and max MSS values
Origami74
