quic

QUIC (RFC 9000 / 9001 / 9002) for Kotlin/Native on top of com.netonstream:io. The first version replicates quinn 0.11.12 (quinn-proto). Maven coordinate com.netonstream:quic, package neton.quic.

Specification and implementation record: SPEC.md.

Status

Real TLS works and quinn interop passes in both directions (SPEC §11.9), so the QUIC protocol and its TLS layer are complete for this version except 0-RTT, which is a separate later batch. Tested on macOS arm64 and Linux x64 (epoll and io_uring).

What exists (SPEC §11.1–11.10):

• varint and frame codecs, and packet protection and header protection on openssl-kotlin primitives;
• streams, flow control and datagrams;
• congestion control (NewReno, Cubic, BBR), pacing, RTT estimation, MTU discovery, packet spaces and ACKs;
• the connection state machine (quinn's connection/mod.rs) and the endpoint (routing, Retry and tokens, version negotiation, stateless reset);
• real TLS 1.3 (SPEC §4, §11.9): TlsSession, TlsClientConfig and TlsServerConfig, implemented in this library on OpenSSL 4.0.2's third-party QUIC TLS interface through openssl-kotlin's raw bindings — certificate chain and host name / IP verification against explicitly given trust anchors (no insecure default), optional client authentication, ALPN, the QUIC transport parameters extension, TLS alerts as CRYPTO_ERROR, 1-RTT key updates, the exporter, with explicit exactly-once release of every native object and a GC cleaner only as a backstop;
• deterministic release of native key contexts and TLS sessions: explicit ownership and release points;
• the driver layer (SPEC §3, §11.8): the endpoint, connection and stream API on neton-io UDP sockets on one reactor, with receive and send budgets, the lifecycle rules as explicit close(), streams as neton-io IoStream;
• quinn's connection, token and driver tests (the TLS-dependent ones on real TLS; the rest run on either the real session or the test double, NETON_QUIC_TEST_TLS=real); the whole suite passes on both (SPEC §11.11), the 0-RTT tests skip on real TLS with the reason printed, and real TLS is checked to decline 0-RTT cleanly;
• verification under an impaired network (SPEC §11.10): seeded loss, reordering, duplication and delay in the protocol-level simulation and through a UDP relay for the real driver — bulk transfer at 1/5/20% loss, lost handshake flights, key updates, resets and stops, closes under loss, exhausted flow-control credit, chaos soaks; two bugs found and fixed (both also in quinn 0.11.12); a third, found running the suite on real TLS: a server connection taken before the handshake completed could not open streams when the ClientHello spanned two datagrams (also in quinn 0.11.12, SPEC §11.11); 605 tests.
• two-way interop with quinn 0.11 (interop/quinn-peer): handshake with certificate verification and ALPN, bidirectional stream echo, key updates initiated by each side, application close, and the rejection cases.

What is missing:

• 0-RTT (session tickets, early data keys, early data acceptance) — a separate later batch; tickets and early data are off.
• The server sends no 0.5-RTT data: OpenSSL yields the server's 1-RTT read secret only after the client's Finished.
• Tests have run on macOS arm64 and Linux x64 only; the other targets are compile-checked.
• FairnessTest has latency bounds that a heavily loaded host can exceed (seen at a load average above 100 on the development Mac); SPEC §11.11 records the measurements.
• quic-interop-runner and the performance comparison with quinn (SPEC §6).

quic-testkit (test-only) holds the TLS test double (MockTls) and a test PKI (TestPki) that generates certificates with OpenSSL at test time. Neither may be used by production code.

Building and testing

./gradlew :quic:macosArm64Test               # or linuxX64Test
NETON_QUIC_TEST_TLS=real quic/build/bin/macosArm64/debugTest/test.kexe   # the whole suite on real TLS