2293f7d2d5
The session-layer handshake now uses the 3-message XK pattern instead of the 2-message IK pattern, providing stronger initiator identity hiding. The initiator static key is deferred to msg3 and encrypted under the es+ee DH chain, so eavesdroppers cannot identify the initiator from the handshake. XK pattern: -> e, es (msg1) / <- e, ee + epoch (msg2) / -> s, se + epoch (msg3) Key changes: - Add XK handshake methods alongside existing IK methods in noise module - Add SessionMsg3 wire format and FSP_PHASE_MSG3 (0x03) prefix - Replace Responding state with AwaitingMsg3 in session state machine - Rewrite session handlers: handle_session_setup defers identity to msg3, handle_session_ack processes msg2 and sends msg3, new handle_session_msg3 completes the responder handshake and registers identity - Link-layer (FMP) continues to use Noise IK unchanged - Add comprehensive XK unit tests and update all integration tests
FIPS: Free Internetworking Peering System
A distributed, decentralized network routing protocol for mesh nodes connecting over arbitrary transports.
Status: Experimental / Pre-release
FIPS is under active development. The protocol and APIs are not stable. Expect breaking changes.
Overview
FIPS is a self-organizing mesh network that operates natively over a variety of physical and logical media — local area networks, Bluetooth, serial links, radio, or the existing internet as an overlay. Nodes generate their own identities, discover each other, and route traffic without any central authority or global topology knowledge.
FIPS uses Nostr keypairs (secp256k1/schnorr) as native node identities, making every Nostr user a potential network participant. Nodes address each other by npub, and the same cryptographic identity used in the Nostr ecosystem serves as both the routing address and the basis for end-to-end encrypted sessions across the mesh.
Features
- Self-organizing mesh routing — spanning tree coordinates and bloom filter candidate selection, no global routing tables
- Multi-transport — UDP/IP overlay today; designed for Ethernet, Bluetooth, serial, radio, and Tor
- Noise encryption — hop-by-hop link encryption plus independent end-to-end session encryption
- Nostr-native identity — secp256k1 keypairs as node addresses, no registration or central authority
- IPv6 adaptation — TUN interface maps npubs to fd00::/8 addresses for unmodified IP applications
- Metrics Measurement Protocol — per-link RTT, loss, jitter, and goodput measurement
- Zero configuration — sensible defaults; a node can run with no config file
Quick Start
Requirements
- Rust 1.85+ (edition 2024)
- Linux (TUN interface requires
CAP_NET_ADMINor root)
Build
git clone https://github.com/jmcorgan/fips.git
cd fips
cargo build --release
Run
# With default configuration (ephemeral identity, default ports):
sudo ./target/release/fips
# With a configuration file:
sudo ./target/release/fips -c fips.yaml
See docs/design/fips-configuration.md for the full configuration reference.
Multi-node Testing
See testing/ for Docker-based integration test harnesses including static topology tests and stochastic chaos simulation.
Documentation
Protocol design documentation is in docs/design/, organized as a layered protocol specification. Start with fips-intro.md for the full protocol overview.
Project Structure
src/ Rust source (library + daemon binary)
docs/design/ Protocol design specifications
testing/ Docker-based integration test harnesses
benches/ Criterion benchmarks
License
MIT — see LICENSE.