Files

T

enricobuehler 76ac3cf867 fix(core): five sweep lows — seal-lane fallback, flush partial, codec echo, idle clamp, pair-name UTF-8

From the 2026-07-20 punktfunk-core quality sweep's adjudicated lows
(~/punktfunk-sweeps/punktfunk-core-2026-07-20.json), each with a
regression test:

- session: the two-lane seal's dead-worker fallback dropped the frame's
  back half and returned Ok with half an access unit; the corpse lane
  was also never respawned. The send-failure arm now reclaims the tail
  (single-lane seals the WHOLE frame) and both failure arms drop the
  lane so the next large frame respawns it. A recv-side death now
  surfaces as an error instead of silent truncation.
- reassemble: Reassembler::reset() left pending_partial parked, so a
  pre-flush stale partial survived Session::flush_backlog and was
  delivered as the first "frame" after a jump-to-live.
- caps: resolve_codec echoed a non-conformant multi-bit preferred byte
  verbatim (downstream from_wire folds it to HEVC — possibly outside
  the shared set). It now isolates one bit of the intersection.
- endpoint: stream_transport_idle only floored the value; an absurd
  operator-supplied idle timeout blew past QUIC's VarInt ms ceiling and
  panicked host startup through the expect. Clamped to 1s..1h.
- pairing: PairRequest::encode cut the device name at a raw byte-64
  boundary, splitting multi-byte UTF-8 (host showed U+FFFD forever);
  it now shares Hello's char-boundary truncate_to.

The frozen-FEC-ceiling finding (reassemble.rs:109) was already fixed on
main by the sweep's high-severity commit — skipped as stale.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

2026-07-20 18:16:02 +02:00

benches

fix(core): receive path — replay window covers the loss window, zero-alloc open

2026-07-10 14:55:06 +02:00

src

fix(core): five sweep lows — seal-lane fallback, flush partial, codec echo, idle clamp, pair-name UTF-8

2026-07-20 18:16:02 +02:00

tests

perf(core): ref-based FEC encode — packetize shards reference the frame in place

2026-07-10 15:16:07 +02:00

vendor/fec-rs

rename: lumen → punktfunk, everywhere

2026-06-10 13:11:59 +00:00

build.rs

chore(core): fix build.rs + crate-doc drift left by the W7/W8 splits

2026-07-20 18:08:39 +02:00

Cargo.toml

refactor(core): consolidate the fingerprint-pinning verifier into core::tls

2026-07-16 15:36:29 +02:00

cbindgen.toml

fix(core,host): make the native data plane survive real Wi-Fi links

2026-07-07 07:35:08 +02:00

README.md

docs: repo-wide housekeeping — sync README & docs with the code as shipped

2026-07-10 09:13:42 +02:00

README.md

punktfunk-core

The shared protocol core — the one place where punktfunk's transport, forward error correction, and crypto live. It's linked into the host and every native client, so there's exactly one implementation of the wire format everywhere.

Written in Rust with no async on the per-frame path (native threads only). It exposes both a normal Rust API and a stable, versioned C ABI, so the Swift and Kotlin clients — and any C embedder — link the same code as the Rust ones.

What's in here

Transport & session (session.rs, transport/, packet.rs) — the punktfunk/1 data plane over raw UDP: packetization, reassembly (with attacker-bounded limits), pacing, and socket tuning.
FEC (fec/) — the wall-breaker. Two codes:
- GF(2⁸) classic Reed–Solomon with the Cauchy generator matrix — byte-identical to the nanors library Moonlight uses, so our parity is decodable by a stock Moonlight client.
- GF(2¹⁶) Leopard-RS (SIMD, O(n log n)) — up to 65535 shards/block, which removes the ~1 Gbps FEC ceiling. punktfunk/1 negotiates this one.
Crypto (crypto.rs) — AES-128-GCM session encryption with per-direction nonce salts and sequence-as-AAD; SPAKE2 PIN pairing lives behind the quic feature.
QUIC control plane (quic.rs, client.rs, feature quic) — the Hello/Welcome/Start handshake, cert pinning/TOFU, reverse audio, and the embeddable NativeClient connector. This is the only place tokio/quinn are allowed; the feature is off by default so the core stays runtime-free.
C ABI (abi.rs) — the versioned surface (punktfunk_abi_version(), PunktfunkConfig carrying its own struct_size) that generates include/punktfunk_core.h via cbindgen at build time.

Build outputs

The crate builds three ways at once (crate-type = ["lib", "cdylib", "staticlib"]):

Output	Used by
`lib` (rlib)	the host, probe, and tools link it as a normal Rust crate
`cdylib` (`.so`/`.dylib`)	the Swift / Kotlin clients via the C ABI
`staticlib` (`.a`)	the C test harness and static embedding

Test

cargo test -p punktfunk-core                 # unit + proptest + loopback
cargo run  -p loss-harness                   # FEC loss-resilience sweep (no network needed)
bash crates/punktfunk-core/tests/c/run.sh    # standalone C-ABI link + round-trip proof

Design invariants (do not regress)

One core, linked everywhere — protocol/FEC/crypto live only here, behind the stable C ABI.
No async on the hot path — the per-frame pipeline is native threads only; quic (tokio/quinn) is control-plane only, feature-gated, off by default.
Security hardening stays intact — the reassembler bounds attacker-controlled fields before allocating; AES-GCM keeps per-direction nonce salts + seq-as-AAD; the ABI checks struct_size. Regression tests exist — keep them green.

punktfunk-host — the streaming host built on this core
Clients — the apps that link this core over the C ABI (or directly, in Rust)
punktfunk-planning: implementation-plan.md (internal planning repo) — why GF(2¹⁶) FEC, the latency budget, and the architecture thesis

README.md Unescape Escape

punktfunk-core

What's in here

Build outputs

Test

Design invariants (do not regress)

Related

README.md