Files

T

enricobuehler ed0ce5dc6d feat(core): zero-copy pooled reassembly — shards land at their final AU offset

Rewrite the client Reassembler around one whole-frame buffer per frame:
frame_bytes rides in every header and packetize geometry is
deterministic (every non-final block is exactly max_data_per_block data
shards), so a data shard's final AU offset is computable on arrival —
copy it there once, straight from the decrypt ring. New
ErasureCoder::reconstruct_into decodes ONLY the missing shards directly
into the frame buffer's holes (gf16 native; gf8 legacy shim); received
recovery shards ride pooled shard-sized buffers. The completed buffer
IS Frame::data.

Deletes the per-shard to_vec + per-block concat + final AU concat
(~178k allocs and a double copy of every byte per second at 2 Gbps —
the pump wall the 2026-07-14 sweeps measured at 98.9% of an M3 Ultra
core). Reassembly now costs ~0.4 µs/packet in-stream.

The eager buffer changes the hostile-header exposure, so two new
firewalls: derived-geometry validation (a header lying about its
data_shards/block_count vs its own frame_bytes is dropped before it can
scribble across another shard's range) and an in-flight allocation
budget (IN_FLIGHT_BUF_FACTOR × max_frame_bytes) so a window of tiny
first-shards can't commit gigabytes.

Behavior parity pinned by the existing suite (all green unchanged) plus
new end-to-end roundtrips through the real Packetizer (multi-block +
partial tail, loss within budget, reversed delivery, duplicates, empty
frame, unrecoverable block ages out, budget enforcement). loss-harness
recovery curve identical; pipeline bench: gf8/1MB +42%, gf16 neutral
(host-encode dominated). Known pre-existing quirk kept as-is: reversed
delivery reconstructs early (data+recovery ≥ k) and counts late-not-lost
shards into fec_recovered_shards.

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

2026-07-14 19:08:15 +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

feat(core): zero-copy pooled reassembly — shards land at their final AU offset

2026-07-14 19:08:15 +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

rename: lumen → punktfunk, everywhere

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

Cargo.toml

feat(transport): Windows DSCP via qWAVE flows — PUNKTFUNK_DSCP now real on the wire there

2026-07-10 15:59:23 +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