Re-express the handshake-state carrier collapse onto the XX code: the leg's
handshake_state field is deleted and the displayed state is derived from the
peer machine's phase, with failure carried on the machine (a send_failed flag
that preserves the handshake phase) rather than on the leg. The next projection
maps the SentMsg2 responder phase to received_msg1 and the anonymous-dial
Discovered phase to sent_msg1; the three initiator send-failure sites carry
failure via send_failed. Telemetry strings, wire bytes, index allocation, and
stale-connection reaping are byte-identical to next.
The connection leg's HandshakeState field duplicated the peer machine's
handshake phase. Delete it and derive the displayed handshake state string
from the machine's PeerState, looked up by link id (mirroring the resend
count). Move the failure signal onto the machine: a send_failed flag that
preserves retransmit eligibility (the machine stays in its handshake phase),
alongside the existing Failed state. The leg's crypto self-gates now guard on
Noise handle presence instead of the deleted phase field, and mark_failed
only drops the handle. Telemetry strings, wire bytes, index allocation, and
the stale-connection reaping are byte-identical for all normal paths.
Carries the dead-code deletion (PeerSlot enum, PeerConnection resend
API) and the module-doc liveness corrections. Hand-resolved the doc
conflicts with next-appropriate wording: the executor module doc names
the live msg3 decision-machine path (PromoteToActive /
SwapToInboundSession / RekeyRespondTrigger) while keeping the still-true
msg1-inline dormancy note; the peer_machines field doc reflects next's
promote-time established() births; the machine module doc drops the
stale unwired claims, including the provisional-and-unwired note on the
msg3 trigger variants which are live.
PeerSlot (and its entire impl surface) was referenced only by its own
module tests and the lib.rs re-export; peer storage has always used the
separate connections/peers maps. PeerConnection's resend_count/
next_resend_at_ms/record_resend delegations had no production callers:
the live resend counter is machine-sourced (connection_resend_count reads
the per-peer machine), and the FSP session layer uses SessionEntry's own
methods. ConnectionState::next_resend_at_ms is now test-only (its
remaining callers are the fmp state unit tests) and marked cfg(test).
The PeerSlot unit tests go with the enum; test_resend_count_tracking is
dropped because the delegation target's schedule arithmetic is already
covered by the fmp resend_bookkeeping test.
Replace fixed 1KB bloom filters with variable-size filters (512B-32KB)
that adapt to each node's position in the spanning tree.
Core changes:
- Internal storage: Vec<u8> → Vec<u64> for word-level operations
- Delta compression: XOR diff with word-level RLE, sequence-based
NACK protocol for full retransmit recovery
- Size conversion: fold (large→small) and duplicate (small→large)
with auto-converting merge for mixed-size filter combination
- Native-size storage: peer filters stored at advertised size for
full-resolution routing queries, converted only for outgoing filter
- Adaptive sizing: outgoing fill ratio drives step-up/step-down
between size classes with hysteresis (20%/5% thresholds)
- Filter size decoupled from FMP negotiation: announced dynamically
in filter updates, bit 7 and TLV field 1 removed from handshake
Wire format: FilterAnnounce gains flags byte (delta bit), base_seq
field, RLE-compressed payload. New FilterNack message (0x21) for
out-of-sequence delta recovery.
Redesign shared-media transport framing now that XX replaces IK:
- Ethernet: unified 4-byte header [type][flags][length:2 LE] for all
frame types, effective MTU now if_mtu - 4
- Beacons: strip 32-byte pubkey (34 → 5 bytes), identity learned from
XX handshake msg2/msg3 instead of beacon
- BLE: remove pre-handshake pubkey_exchange() and cross-probe
tie-breaker, both unnecessary with XX
- Discovery: support anonymous connections (pubkey_hint: None) with
address-based dedup for shared-media transports
- Post-handshake identity hooks in handle_msg2/msg3 for self-detection
and future allow/deny list filtering (IDEA-0047)
- Delete PROTOCOL_NAME_IK, PROTOCOL_NAME_XK and all IK/XK methods
- Remove Ik/Xk variants from NoisePattern enum
- Rename XX methods to drop xx_ prefix (sole pattern)
- Rename HandshakeMessageType variants from NoiseIKMsg1/NoiseIKMsg2
to Msg1/Msg2, add Msg3 variant (0x03) for XX 3-message flow
- Fix doc comments with correct XX message sizes and descriptions
- Fix stale SessionSetup/SessionAck handshake payload size comments
Replace the 2-message IK handshake with a 3-message XX handshake for
FMP link establishment. XX requires no prior knowledge of the peer's
static key — both identities are revealed during the handshake
(responder in msg2, initiator in msg3). This is the foundation for
the forklift upgrade that enables rolling protocol upgrades.
Changes:
- Noise XX state machine alongside IK/XK (8 unit tests)
- Protocol negotiation payload codec: format byte, packed version
min/max, 64-bit feature bitfield, TLV extensions (11 unit tests)
- FMP wire format version 0→1, msg3 header/builder, TCP stream framing
- FMP handshake switched to XX: PeerConnection 3-message flow,
handle_msg1 simplified (no identity), handle_msg2 sends msg3 and
promotes initiator, new handle_msg3 promotes responder with
restart/rekey/cross-connection detection
- Rekey handshake switched to XX with negotiation payload hash chain
fix (decrypt-and-discard in complete_rekey_msg2/msg3)
- Negotiation payload in msg2/msg3 (FMP version [1,1], features=0)
- Debug logging for handshake promotion paths
- Integration test convergence timeouts adjusted for extra round-trip
Squashed commits:
- Add Noise XX state machine alongside IK/XK
- Add protocol negotiation payload codec
- FMP wire format prep: version 1, msg3 header support
- Switch FMP handshake from Noise IK to XX
- Increase convergence timeouts for XX 3-message handshake
- Fix negotiation hash chain desync in rekey handshake
Bump rand (0.8→0.10), rtnetlink (0.14→0.20), tun (0.7→0.8),
simple-dns (0.9→0.11), socket2 (0.5→0.6), and criterion (0.5→0.8).
Migrate all rand call sites: thread_rng()→rng(), gen()→random(),
gen_range()→random_range(), RngCore→Rng trait. Work around secp256k1
0.30 requiring rand 0.8 by generating random bytes directly and
constructing SecretKey from slice.
Migrate rtnetlink to builder-based API: LinkSetRequest replaced with
LinkUnspec builder + change(), RouteAddRequest replaced with
RouteMessageBuilder.
Remove bloom benchmark (criterion 0.8 incompatible with old harness
config).
Each node generates a random 8-byte startup epoch, encrypted inside
both Noise IK handshake messages (msg1 and msg2). When a peer's msg1
arrives with a different epoch than the stored value, the node tears
down the stale session and processes the msg1 as a new connection,
enabling near-instant restart detection instead of the 30-second
dead timeout.
Wire format impact:
- msg1: 82 -> 106 bytes (added 24-byte encrypted epoch after ss DH)
- msg2: 33 -> 57 bytes (added 24-byte encrypted epoch after se DH)
- Wire msg1: 90 -> 114 bytes, wire msg2: 45 -> 69 bytes
Add message-level retry for Noise IK handshake within the 30s timeout
window. Previously, a lost msg1 or msg2 required the full timeout to
expire before cleanup and retry. Under 10% bidirectional loss (~19%
per attempt), this made connection establishment unreliable.
Initiator resends stored msg1 bytes with exponential backoff (1s, 2s,
4s, 8s, 16s — 5 resends). Responder stores msg2 and resends on
duplicate msg1 receipt. Duplicate msg2 at initiator drops silently
via existing pending_outbound cleanup.
Config: handshake_resend_interval_ms (1000), handshake_resend_backoff
(2.0), handshake_max_resends (5) on node.rate_limit.
P(all 6 attempts fail) under 19% loss = 0.19^6 ≈ 0.005%.
Fix promote_connection() to detect and clean up pending outbound
handshakes to the same peer, not just already-promoted peers. Previously,
when an inbound handshake completed while an outbound was still pending,
the outbound would linger until the 30s timeout.
Add auto-retry for failed outbound connections to auto-connect peers:
- New RetryState struct and node/retry.rs module
- Exponential backoff (default 5s base, max 5 attempts)
- Config: node.max_retries, node.base_retry_interval_secs
- check_timeouts() schedules retries, rx loop processes them
- promote_connection() clears retry state on success
- Remove unused PeerConnection retry fields (state now at Node level)
Move cleanup_stale_connection() logging to callers for context-appropriate
messages.
289 tests pass, clean build.
Johnathan Corgan