14 Commits
Author SHA1 Message Date
Johnathan Corgan 5abf9a9325 docs: four-section /docs/ restructure with new-user content, accuracy pass, and gateway feature-set rewrite
Restructures /docs/ by reader purpose (tutorials, how-to,
reference, design), adds the new-user-progression and
operator-recipe content the prior layout lacked, runs an
accuracy pass against current source across the pre-existing
design docs, and rewrites the gateway feature-set documentation
end-to-end around its actual operational profile (a niche
feature designed for systems already serving DHCP/DNS to a
LAN, with two independent halves — outbound LAN→mesh, inbound
mesh→LAN — sharing one nftables table, one binary, and one
control socket). Top-level README and getting-started rewritten
around two equally-weighted deployment modes (overlay on
existing IP networks; ground-up over non-IP transports).

## Additions

- 11 new tutorials in docs/tutorials/: an 8-step new-user
  progression from single-daemon test-mesh peering through
  to a ground-up two-device mesh, an IPv6-adapter side-trip
  walkthrough, an Advanced Tutorials index, and a hand-held
  OpenWrt walk-through for fips-gateway deployment that
  exercises both halves of the feature.
- 12 new how-tos in docs/how-to/: firewall activation,
  Nostr discovery (resolve / advertise / open across five
  scenarios), Tor onion (directory + control_port modes),
  UDP buffer tuning, unprivileged-user setup, persistent
  identity, host aliases, Bluetooth LE peering, MTU
  diagnostics, manual Linux-host gateway deployment (covers
  both halves), gateway troubleshooting (organised by half),
  and a section index.
- 9 new reference docs in docs/reference/: configuration,
  wire formats, control-socket protocol, four CLI references
  (fips, fipsctl, fipstop, fips-gateway), security posture
  matrix, and Nostr events catalog. Configuration and
  wire-formats are renamed-and-extended from prior design/
  versions; the other seven are net-new.
- 6 new design docs: fips-concepts, fips-architecture, and
  fips-prior-work split out of the deleted fips-intro.md;
  consolidated fips-mmp and fips-mtu aggregations; and a
  new generic port-advertisement-and-nat-traversal doc
  (Nostr-signaled port advertisement plus UDP NAT-traversal
  protocol, FIPS as an example implementation, suitable for
  eventual NIP submission).
- Top-level docs/getting-started.md walking through the
  binary-installer-only Install story.
- packaging/common/hosts pre-populated with the eight public
  test-mesh nodes so shortnames resolve out of the box on
  every fresh install.

## Changes

- 23 wire-format diagrams relocated to reference/diagrams/
  alongside the wire-formats move.
- 4 design diagrams corrected against source code
  (fips-protocol-stack, fips-identity-derivation,
  fips-coordinate-discovery, fips-routing-decision).
- 10 pre-existing design docs reconciled with current
  source. Numeric corrections: stale link-MMP report bounds
  (now [1s, 5s] with 200 ms cold-start floor); UDP default
  MTU (now 1280, IPv6 minimum); node_addr formula
  (SHA-256(pubkey)[..16]); Noise patterns (IK at link, XK
  at session); peer-ACL semantics (strict allowlist requires
  ALL in peers.deny); daemon DNS upstream ([::1]:5354);
  on-the-wire bloom-filter size (1,071 bytes); obsolete
  Cargo-feature references (PR #79 dropped them) removed.
- Transport framing tightened across the docs: TCP is for
  UDP-filtered networks (not NAT traversal); Tor is a
  deployment mode (not failover); WebSocket dropped (not a
  shipped FIPS transport); WiFi promoted to Implemented via
  Ethernet in infrastructure mode; classic-Bluetooth row
  removed (BLE is the only Bluetooth-mode transport).
- docs/design/fips-gateway.md rewritten end-to-end to lead
  with the niche-feature framing and the two-halves
  structure. Title moved from "FIPS Outbound LAN Gateway"
  to "FIPS Gateway"; architecture section describes the
  common machinery (the fips-gateway service, the nftables
  table, the control socket) before splitting into separate
  "Outbound Half" and "Inbound Half" sections of equal
  weight; security considerations split per-half; no Future
  Work section (speculative directions live in the project
  tracker, not in protocol design docs). Inbound port
  forwarding is a first-class half rather than a buried
  "Implemented Extensions" subsection.
- Gateway terminology unified across all gateway docs as a
  separate Linux service running alongside the fips daemon
  (its own systemd unit / OpenWrt init script). Container-
  pattern terms (sidecar) are reserved for the
  Docker/Kubernetes sidecar deployment examples — the
  testing/sidecar/ tree, examples/k8s-sidecar/,
  examples/sidecar-nostr-relay/,
  examples/wireguard-sidecar-macos/, and the related
  CHANGELOG / top-level README entries — where the term
  carries its standard container meaning.
- Net-new design body content: rekey section in
  fips-mesh-layer (Noise IK msg1/msg2 over the established
  link, K-bit cutover, drain window, smaller-NodeAddr-wins
  tie-breaker on dual-init); Mesh Size Estimation and
  Antipoison FPR Cap sections in fips-bloom-filters;
  Mesh-Interface Query Filter subsection in
  fips-ipv6-adapter; failure-suppression knobs and clock-
  skew tolerance in fips-nostr-discovery; loop-rejection
  and mid-chain ancestor swap added to spanning-tree
  propagation / stability rules; Priority Chain in
  fips-mesh-operation renumbered to match the
  routing-decision diagram.
- Top-level README: dropped the stale nostr-discovery
  cargo-feature parenthetical. docs/README.md and the four
  section READMEs (tutorials, how-to, reference, design)
  refreshed for the new structure; index rows reflect both
  halves of the gateway feature and the new fips-gateway
  CLI reference.
- Cargo.toml [package.metadata.deb] assets path updated for
  the fips-security.md move; .gitignore /reference/ rule
  anchored to repo root so docs/reference/ is trackable.
- packaging/openwrt-ipk/files/etc/fips/fips.yaml
  configuration-doc URL updated to the new
  docs/reference/configuration.md location.

## Deletions

- docs/design/fips-intro.md (split into the three new intro
  design docs).
- docs/design/document-relationships.svg (orphan, no longer
  referenced).
- docs/proposals/ tree removed; the only proposal it
  contained (the Nostr UDP hole-punch protocol) was
  rewritten as the new generic
  design/port-advertisement-and-nat-traversal.md.
2026-05-08 03:02:12 +00:00
Johnathan Corgan 00e26765bd Design documentation illustration and review pass
Wire format diagrams:
- Add 24 SVG diagrams covering every FMP and FSP wire format: common
  prefix, established frame headers, Noise IK handshake messages,
  handshake flow, TreeAnnounce, AncestryEntry, FilterAnnounce,
  LookupRequest/Response, SessionDatagram, Disconnect, SenderReport,
  ReceiverReport, FSP complete message, SessionSetup/Ack/Msg3,
  PathMtuNotification, CoordsRequired, PathBroken, and MtuExceeded
- Replace ASCII art in fips-wire-formats.md with SVG references
- Apply text edits to fips-mesh-layer.md, fips-mesh-operation.md,
  fips-transport-layer.md, and fips-ipv6-adapter.md

Spanning tree dynamics:
- Add 12 topology SVG diagrams: node join (overview + 3-panel steps),
  three-node convergence (4-panel), link addition with depth labels,
  link removal, partition formation, and 6 real-world example diagrams
  (office, mixed-link, two-site WAN topologies)
- Rewrite all code blocks to narrative prose with diagram references
- Add inline prior art attributions distinguishing Yggdrasil-derived
  concepts from FIPS-novel contributions
- Add 3 new references (De Couto ETX, IEEE 802.1D, RFC 2328 OSPF) and
  Prior Art summary
- Remove outdated sections: indirect partition note, integration test
  gaps, DHT-based lookup reference
- Change "must elect a new root" to "must rediscover its new root"

Spanning tree design review (fips-spanning-tree.md):
- Rename "Root Election" to "Root Discovery" across docs
- Add "What Is a Spanning Tree?" introductory section
- Add parent selection intro explaining self-organization role
- Fix tree distance example: 4 hops, not 2
- Clarify timestamp field as advisory only
- Remove unimplemented ROOT_TIMEOUT and TREE_ENTRY_TTL from timing
  parameters and implementation status tables

Bloom filter design review (fips-bloom-filters.md):
- Add "What Is a Bloom Filter?" intro section
- Rewrite Purpose section to frame filters as routing path identification
- Correct FPR analysis (old values were 3-50x overstated)
- Add Filter Occupancy Model based on network size and tree position
- Fix filter expiration to describe actual MMP-based cleanup
- Combine Scale Considerations with Size Classes after Wire Format
- Fix stale FPR values in src/bloom/mod.rs comments

Session layer review (fips-session-layer.md):
- Add inline prior art attributions: Noise Protocol Framework, WireGuard,
  DTLS (RFC 6347), IKEv2 (RFC 7296), RFC 1191 PMTUD, Yggdrasil, NIP-44
- Replace warmup state machine ASCII art with SVG diagram
- Convert CoordsWarmup wire format code block to prose
- Add External References section with full citations

Level 5 implementation doc cleanup:
- Delete fips-software-architecture.md (redundant with protocol layer docs)
- Delete fips-state-machines.md (Rust tutorial, not protocol design)
- Add fipsctl command reference to README.md
- Update cross-references in fips-intro.md, docs/design/README.md,
  fips-transport-layer.md, fips-configuration.md

Fixes:
- Correct fd::/8 to fd00::/8 in fips-session-layer.md,
  fips-identity-derivation.svg, and fips-node-architecture.svg
- Fix config example MTU: 1197 → 1472 in fips-configuration.md

File organization:
- Move all SVG diagrams into docs/design/diagrams/ subdirectory
- Update all diagram references to use new paths
2026-02-24 17:32:37 +00:00
Johnathan Corgan c1820e689d Update design docs for replay suppression, MMP backoff, and flap dampening
- fips-configuration.md: add flap_threshold, flap_window_secs,
  flap_dampening_secs to tree config table and YAML reference
- fips-spanning-tree.md: add flap dampening to Stability Mechanisms,
  Timing Parameters, and Implementation Status tables
- spanning-tree-dynamics.md: update Known Limitations to reflect flap
  dampening implementation, revise impact text
- fips-session-layer.md: add Send Failure Backoff subsection under
  Session-Layer MMP
- fips-mesh-layer.md: add log suppression note to Replay Protection
2026-02-23 20:28:17 +00:00
Johnathan Corgan 0d93a19e07 Implement cost-based parent selection with periodic re-evaluation
Cost-based parent selection:
- Replace depth-only parent selection with effective_depth = depth + link_cost
- link_cost computed from locally measured MMP metrics: etx * (1.0 + srtt_ms / 100.0)
- Prevents bottleneck subtrees in heterogeneous networks where a LoRa link
  at depth 1 would otherwise always beat fiber at depth 2
- Configurable hysteresis (default 0.2) prevents marginal parent switches
- Configurable hold-down timer (default 30s) suppresses re-evaluation
  after parent switch
- Mandatory switches (parent lost, root change) bypass both safeguards
- Link costs passed as HashMap parameter to keep TreeState pure

Periodic re-evaluation:
- evaluate_parent() was only called on TreeAnnounce receipt or parent loss;
  after tree stabilization, link degradation went undetected
- Added timer-based re-evaluation (reeval_interval_secs, default 60s) that
  calls evaluate_parent() from the tick handler with current MMP link costs
- Respects existing hold-down and hysteresis safeguards
- Short-circuits when disabled or <2 peers

Design documentation:
- Update 7 design docs to reflect cost-based parent selection
- Replace depth-only algorithm descriptions with effective_depth model
- Replace rejected cumulative path cost spec with local-only design rationale
- Rewrite Example 2 (heterogeneous links) for local-only cost model
- Update config docs: parent_switch_threshold replaced by parent_hysteresis,
  hold_down_secs, reeval_interval_secs

Chaos simulation enhancements:
- fips_overrides with deep merge for per-scenario FIPS config customization
- Explicit topology algorithm for deterministic test graphs
- Control socket querying via fipsctl for tree/MMP snapshot collection
- Edge existence validation in netem manager
- Per-link netem policy overrides
- 9 new chaos scenarios covering cost avoidance, depth-vs-cost tradeoffs,
  stability, mixed topologies, periodic re-evaluation, and bottleneck parent

12 new unit tests, 667 total passing, clippy clean.
2026-02-23 17:15:20 +00:00
Johnathan Corgan dc89edf60b Update design docs for session 142 implementation changes
Comprehensive documentation review across 12 files to reflect:
- Noise XK at FSP (was IK), 3-message handshake, SessionMsg3 wire format
- Epoch exchange in Noise handshakes for peer restart detection
- Per-link MTU, min_mtu/path_mtu in lookup packets
- MtuExceeded (0x22) error signal wire format and behavior
- LookupResponse proof now covers target_coords
- Discovery reverse-path routing as primary (not greedy)
- Control socket architecture and fipsctl binary
- FSP handshake state machine (Initiating/AwaitingMsg3/Established)
- Root timeout framing updated for heartbeat cascading
2026-02-22 23:03:00 +00:00
Johnathan Corgan d46dc874ef Restructure design docs around protocol layers
Reorganize FIPS design documentation from implementation-centric
structure (routing, gossip protocol, wire protocol, transports) to
protocol-layer organization with clear service boundaries.

New documents (8):
- fips-transport-layer.md — transport layer spec
- fips-link-layer.md — FLP spec (peer auth, link encryption, forwarding)
- fips-session-layer.md — FSP spec (end-to-end encryption, sessions)
- fips-ipv6-adapter.md — IPv6 adaptation (TUN, DNS, MTU enforcement)
- fips-mesh-operation.md — routing, discovery, error recovery
- fips-wire-formats.md — consolidated wire format reference
- fips-spanning-tree.md — tree algorithm reference
- fips-bloom-filters.md — bloom filter math reference

Rewritten (2):
- fips-intro.md — breadth-first intro with layer model diagrams
- fips-software-architecture.md — slimmed to stable decisions

Updated (3):
- spanning-tree-dynamics.md — removed stale root refresh, aligned terminology
- fips-configuration.md — fixed priority type (u16 → u8)
- fips-state-machines.md — synced code examples with codebase

Deleted (6): fips-transports.md, fips-wire-protocol.md,
fips-gossip-protocol.md, fips-session-protocol.md, fips-routing.md,
fips-tun-driver.md (content absorbed into new structure)
2026-02-17 04:50:04 +00:00
Johnathan Corgan 20467f5650 Design doc audit: correct 7 code/doc divergences across 5 documents
Systematic review identified 12 divergences between design docs and
implementation. Corrected 7, deferred 3 for further analysis.

Changes:
- Session tie-breaker: npub → node_addr ordering
- Dual cache architecture: CoordCache (50K, TTL 300s) and RouteCache
  (10K, LRU) with correct names, sizes, and eviction policies
- LookupResponse routing: greedy-only → find_next_hop + reverse-path
- Discovery TTL default: 8 → 64
- Parent selection: v1 depth-only algorithm, cost metrics marked v2
- Leaf-only mode: implementation status note added
- Data overhead: 36-byte → 38-byte header
- Verification pass fixed stale cache/header refs in session protocol doc
2026-02-14 19:26:25 +00:00
Johnathan Corgan 5d7af5b478 Implement FilterAnnounce send/receive, remove TTL/K-hop scoping
Add bloom filter reachability announcement protocol:
- FilterAnnounce encode/decode (wire format 0x20, 1035 bytes)
- node/bloom.rs: send/receive with debounce, split-horizon loop prevention
- Handler wiring: dispatch, tick, peer promotion/removal, cross-connection
- Five integration tests: 10-node, star, chain, ring, 100-node convergence

Remove TTL/K-hop mechanism from code and design docs after discovering
that per-entry TTL scoping is fundamentally incompatible with flat bloom
filter merge + regeneration architecture. Each node re-originates filters
with fresh TTL, making propagation unbounded regardless of TTL value.
Split-horizon remains the primary loop prevention mechanism.

Document spanning tree known limitations (v1) in spanning-tree-dynamics.md.

316 tests pass, clean build, zero warnings.
2026-02-11 03:16:25 +00:00
Johnathan Corgan 5e7342c57c Standardize naming conventions across docs and source
Rename NodeId to NodeAddr and npub to pubkey throughout documentation
and source code for consistency with the established identity model.
Add FIPS API vs IPv6 adapter overview to session protocol document.
Add transport address terminology note to wire protocol document.
2026-02-06 04:03:32 +00:00
Johnathan Corgan a8115f7622 Unify Noise IK for both link and session layers
Design change: Session layer now uses Noise IK pattern (previously KK),
matching the link layer. Rationale: initiator knows destination npub,
responder learns initiator identity from handshake - same asymmetry as
link connections.

Document consistency fixes:
- Auth* events → Noise IK msg1/msg2 terminology in state machines
- PeerId → NodeId in routing code examples
- BloomUpdate → FilterAnnounce terminology
- Updated cross-references and tables
2026-02-02 02:25:39 +00:00
Johnathan Corgan e582f50de7 Session 51: Create fips-intro.md protocol introduction
New comprehensive protocol introduction replacing fips-design.md:
- What is FIPS / Why FIPS: goals and design philosophy
- How It Works: transport, spanning tree, bloom filters, routing overview
- Prior Work: Yggdrasil/Ironwood, Noise Protocol, WireGuard references
- Identity System: npub/nsec, node_id derivation, fd00::/8 addressing
- Two-Layer Encryption: link layer (Noise IK), session layer (Noise KK)
- Spanning Tree Protocol: root election, parent selection, gossip limits
- Bloom Filter Routing: filter explanation, propagation, discovery
- Transport Abstraction: transport/link distinction, bridging, types
- Security: threat model, Sybil resistance, accurate metadata exposure

Updated cross-references in README.md and other design docs.
Deleted obsolete fips-design.md.
2026-02-01 20:51:01 +00:00
Johnathan Corgan 7c2e11c5de Session 50: Design document reorganization and gossip protocol
- Create fips-gossip-protocol.md with wire formats for TreeAnnounce,
  FilterAnnounce, LookupRequest/LookupResponse
- Refactor fips-routing.md to reference gossip protocol for wire formats
- Update fips-session-protocol.md: remove reconciliation section,
  condense peer connection section
- Update spanning-tree-dynamics.md with gossip protocol reference
- Reorganize README.md with suggested reading order
- Remove obsolete fips-architecture-review.md
2026-02-01 17:42:17 +00:00
Johnathan Corgan fc20c47119 Resolve architecture review items and reconcile terminology
- Standardize coordinate ordering to [self, parent, ..., root] across all docs
- Fix 8 coordinate ordering instances in spanning-tree-dynamics.md
- Clarify cache naming: discovery.cache and session.cache configure Node.coord_cache
- Reconcile Transport vs Link terminology:
  - Transport = interface/medium (UDP socket, Ethernet NIC)
  - Link = connection instance to a specific peer
- Update fips-design.md: replace FipsLink trait with architecture reference
- Rename fips-links.md to "Transport Protocols", add terminology section
- Update review doc: mark items 1, 5, 13 RESOLVED; items 2-4, 7 DEFERRED
2026-01-29 17:00:33 +00:00
Johnathan Corgan 7194200f55 Add docs/design directory with protocol specifications
Move design documents from working directory into source tree:
- fips-design.md - Full protocol design specification
- spanning-tree-dynamics.md - Spanning tree protocol dynamics study

Add README index files for docs/ and docs/design/.
2026-01-25 22:02:54 +00:00