Claude
0fea36fa56
Records the qlog-driven debugging session that fixed: - QlogWriter close-race breaking healthy connections - QlogWriter per-event flush stalling the connection lock - PTO probe missing CRYPTO retransmit (aioquic close) - Retry test PN-reuse violation (RFC 9001 §5.7) - Multiplexing 30s timeout - Hung-stream blocks the parallel-await chain Still open: - v2 testcase (needs RFC 9369 implementation) - Multiplexing throughput on Mac+Rosetta - Server role (would unlock handshakeloss vs aioquic) https://claude.ai/code/session_01HcvfQq1ttPV9PkRoJb4nyT
246 lines
13 KiB
Markdown
246 lines
13 KiB
Markdown
# quic-interop-runner endpoint — Phase 0 scaffolding
|
||
|
||
Date: 2026-05-06
|
||
|
||
## Why
|
||
|
||
We want the [`quic-interop-runner`](https://github.com/quic-interop/quic-interop-runner)
|
||
matrix as a **bug-finding harness**, not a vanity scoreboard. Each peer impl
|
||
(quiche, aioquic, picoquic, ngtcp2, msquic, mvfst, lsquic, neqo, kwik) enforces
|
||
different parts of RFC 9000/9001/9002/9114 strictly, so failures triangulate
|
||
to specific bugs in `:quic`. The runner's ns-3 sim also exposes loss /
|
||
reorder / migration scenarios that are awkward to reproduce in unit tests.
|
||
|
||
## What's in Phase 0
|
||
|
||
- `:quic-interop` Gradle module (JVM-only application, registered at
|
||
`quic/interop/` via `settings.gradle`).
|
||
- `InteropClient.kt` reads the runner's env-var contract (`ROLE`, `TESTCASE`,
|
||
`REQUESTS`, …) and dispatches by testcase. Phase 0 implements only
|
||
`handshake`; everything else returns `127` (runner-skip).
|
||
- `Dockerfile` based on `martenseemann/quic-network-simulator-endpoint` +
|
||
OpenJDK 21 runtime, copies the `installDist` output.
|
||
- `run_endpoint.sh` sources the base image's `/setup.sh` then execs our JVM
|
||
binary.
|
||
- `Makefile` wrappers: `make build`, `make clean`. (A `make smoke`
|
||
target previously stood up picoquic + our endpoint on a private Docker
|
||
bridge to bisect runner failures from impl failures; dropped once
|
||
the runner reliably exercised both paths.)
|
||
|
||
## Local iteration loop
|
||
|
||
The fast path: `quic/interop/run-matrix.sh` clones the runner alongside
|
||
this repo, sets up a venv, merges our `implementations_quic.json` snippet,
|
||
builds the endpoint image, and invokes `run.py`. All steps are
|
||
idempotent so repeated invocations just iterate.
|
||
|
||
```
|
||
# Single test against the most permissive peer:
|
||
quic/interop/run-matrix.sh -s aioquic -t handshake
|
||
|
||
# A focused triangulation:
|
||
quic/interop/run-matrix.sh -s aioquic -t handshake,chacha20
|
||
quic/interop/run-matrix.sh -s quic-go -t handshake,chacha20
|
||
quic/interop/run-matrix.sh -s picoquic -t handshake,chacha20
|
||
|
||
# Tight inner loop — skip the image rebuild between test selections:
|
||
SKIP_BUILD=1 quic/interop/run-matrix.sh -s aioquic -t transfer
|
||
```
|
||
|
||
Manual flow (if `run-matrix.sh` doesn't fit):
|
||
|
||
```
|
||
make -C quic/interop build
|
||
# Then in a sibling clone of quic-interop-runner, merge our snippet:
|
||
jq -s '.[0] * .[1]' implementations_quic.json \
|
||
../amethyst/quic/interop/quic-interop-runner-snippet.json \
|
||
> implementations_quic.json.new && mv implementations_quic.json.new implementations_quic.json
|
||
python run.py -d -i amethyst -s aioquic -t handshake,chacha20 --log-dir ./logs
|
||
```
|
||
|
||
Inspect `./logs/<run>/client_qlog/*.qlog` in qvis when something breaks.
|
||
|
||
## Phase ladder (excerpt — full plan in conversation)
|
||
|
||
| Phase | Goal | Tests | Exit criterion |
|
||
|---|---|---|---|
|
||
| 0 | Minimum harness | `handshake` | one test reproducible end-to-end ✅ |
|
||
| 1 | Triangulate handshake bugs | + `versionnegotiation`, `chacha20` | green vs aioquic + quiche + picoquic |
|
||
| 2 | Streams + loss + multiplexing | + `transfer`, `multiplexing`, `*loss`, `http3` | `transfer` / `multiplexing` / `http3` ✅ landed; loss tests pending |
|
||
| 3 | Edge cases | `retry`, `resumption`, `zerortt`, `keyupdate`, `rebinding-*`, `blackhole`, `amplificationlimit` | every test green or unsupported-127 with a written reason |
|
||
| 4 | CI gate | nightly Phases 1–2; PR-blocking subset on every push | qlogs uploaded as artifacts on red |
|
||
|
||
## Phase 2 — landed 2026-05-06
|
||
|
||
- Minimal `Http3GetClient` (in `:quic-interop`, NOT `:quic` — interop-test
|
||
surface, not a production HTTP/3 client). Opens the three required
|
||
client uni streams (control + QPACK encoder + QPACK decoder), sends
|
||
empty SETTINGS, then per request opens a bidi stream, encodes a HEADERS
|
||
frame with the four pseudo-headers using the existing literal-only
|
||
`QpackEncoder`, FINs, and reassembles HEADERS+DATA frames from the
|
||
response. Out-of-scope: GOAWAY, PUSH_PROMISE, dynamic QPACK table,
|
||
trailers, priority.
|
||
- `transfer` + `http3` testcases: GET each URL in `REQUESTS` sequentially,
|
||
write each body to `$DOWNLOADS/<basename>`. Status != 200 fails.
|
||
- `multiplexing` testcase: same as `transfer` but issues each GET in a
|
||
parallel `coroutineScope { async { … } }` so the request streams
|
||
genuinely overlap on the wire (what tshark verifies).
|
||
- Aliased sim-driven testcases — these reuse the same client code paths;
|
||
the runner injects the network condition via the ns-3 sim. Failures
|
||
here are exactly the bug-finding signal we want, since they exercise
|
||
loss recovery / RTT estimator / congestion behaviour against real peers:
|
||
- `transferloss` → transfer (random packet loss)
|
||
- `transfercorruption` → transfer (random bit-flip; AEAD AUTH FAIL → drop + retransmit)
|
||
- `longrtt` → transfer (emulated high-latency link)
|
||
- `goodput` → transfer (throughput floor)
|
||
- `crosstraffic` → transfer (competing UDP flows on the same link)
|
||
- `handshakeloss` → handshake (loss during handshake — tests CRYPTO retransmit)
|
||
|
||
## Phase 3 — landed 2026-05-07 (post-quic-go interop)
|
||
|
||
- ALPN per testcase (`:quic-interop`'s `Alpn` enum + per-test switch in
|
||
`InteropClient.main`). quic-go enforces strictly with TLS
|
||
`no_application_protocol` (CRYPTO_ERROR 0x178); aioquic / picoquic accept
|
||
either. Convention: `h3` for `http3`/`multiplexing`, `hq-interop`
|
||
everywhere else.
|
||
- `HqInteropGetClient` (HTTP/0.9 over QUIC) — open bidi, send `GET /path\r\n`,
|
||
FIN, read body until server FINs. No framing, no QPACK. ~30 lines.
|
||
- Multi-stream FIN delivery fix in `QuicConnection.closeAllSignals()`: pre-fix
|
||
iterated only the connection-wide signal channels, leaving every per-stream
|
||
`incomingChannel` open after teardown — coroutines suspended on
|
||
`stream.incoming.collect { ... }` hung forever. Fix iterates `streamsList`
|
||
on close. Three regression tests in `MultiStreamFinDeliveryTest`.
|
||
- `retry` + `ipv6` testcases enabled in dispatch. `retry` rides on agent 3's
|
||
RFC 9000 §17.2.5 + RFC 9001 §5.8 implementation. `ipv6` should "just work"
|
||
via JDK's `DatagramChannel` v6 support; runner-validated when run.
|
||
|
||
## Validated against (as of 2026-05-07 evening)
|
||
|
||
Latest run results before pushing the multi-ALPN fix `acfe815e1`:
|
||
|
||
| Peer | handshake | chacha20 | transfer | http3 | multiplexing |
|
||
|---|---|---|---|---|---|
|
||
| aioquic | ✓ | ✓ | ✓ | ✓ | ✕ (channel-saturation, agent C investigating) |
|
||
| picoquic | ✕ (alpn=hq-interop unsupported, fixed in `acfe815e1`) | ✕ | ✕ | ✓ | ✕ |
|
||
| quic-go | (untested post-fix) | | | | |
|
||
|
||
After `acfe815e1`'s multi-ALPN offer, predictions:
|
||
- picoquic returns to 4/4 (server picks `h3`, we run Http3GetClient).
|
||
- quic-go: handshake / chacha20 / transfer / http3 should green (server picks `hq-interop` for non-h3 tests).
|
||
- aioquic: still 4/5; multiplexing held back by channel-saturation bug.
|
||
|
||
## Phase 4 — landed 2026-05-07 (overnight agents)
|
||
|
||
All three agents merged onto the branch with three rounds of fixup
|
||
(each agent's worktree was based on `main`, not the branch HEAD, so
|
||
they clobbered each other's changes during merge):
|
||
|
||
- **Agent A — VN-handling defense in `:quic`**: configurable
|
||
`initialVersion` on `QuicConnection`, `applyVersionNegotiation`
|
||
state machine, `vnConsumed` latch, downgrade defenses. *NOTE*: the
|
||
runner does not have a `versionnegotiation` testcase (it has `v2`,
|
||
which tests QUIC v2 — we're v1-only). Code stays as defensive
|
||
support for any server that throws a VN at us, but unused by the
|
||
matrix.
|
||
- **Agent B — qlog observer**: `QlogObserver` interface in `:quic`
|
||
with NoOp default + 12 event hooks (packet-sent/received/dropped,
|
||
key-updated, conn-started/closed, loss-detected, PTO-fired,
|
||
transport-params, ALPN, version). `QlogWriter` (Jackson-backed
|
||
JSON-NDJSON) in `:quic-interop`. `InteropClient` reads `$QLOGDIR`
|
||
the runner already sets and writes `client.sqlog` per testcase.
|
||
Drag straight into qvis.quictools.info to see the trace.
|
||
- **Agent C — peer-uni-stream drainer**: `drainPeerInitiatedUniStreamsIntoBlackHole`
|
||
helper on `QuicConnection`, wired into `Http3GetClient.init(scope)`.
|
||
Fixes the multiplexing channel-saturation symptom (server's uni
|
||
streams accumulated bytes in 64-chunk per-stream channels until
|
||
parser tore down with INTERNAL_ERROR ~4.5s into a multi-stream run).
|
||
|
||
## Phase 5 — landed 2026-05-07 (post-overnight bug-hunt)
|
||
|
||
The full overnight session pulled hard on the bugs the matrix exposed.
|
||
qlog turned out to be the unblocking tool — every fix in this phase
|
||
came from staring at a `client.sqlog` and matching it against the RFC
|
||
pages it referenced.
|
||
|
||
| Commit | Diagnosis pattern |
|
||
|---|---|
|
||
| `bd9d717df` | `IOException: Stream closed` from QlogWriter mid-test → observer threw into the send loop, killed connections that had already completed transfer. |
|
||
| `99a1a91de` | qlog stops at t=400ms, no inbound packets → per-event `writer.flush()` stalled the connection lock on macOS Docker filesystem virtualization. |
|
||
| `c0d7b6031` | aioquic `CONNECTION_CLOSE: Packet contains no CRYPTO frame` after PTO probe → our PTO emitted bare PING, not CRYPTO retransmit. Restored agent 2's wiring lost in the qlog merge. |
|
||
| `17b80270d` | runner's retry verdict `Client reset the packet number. Check failed for PN 0` → `applyRetry` reset Initial PN to 0; RFC 9001 §5.7 says PN namespace continues across Retry. New `LevelState.resetForRetry` helper. |
|
||
| `9a74d1d5d` | multiplexing qlog showed STREAM frames still arriving at t=31s when local timeout fired → bumped `TRANSFER_TIMEOUT_SEC` 30→60. Doesn't fix throughput, just lets the test budget match the workload. |
|
||
| `32ccbd2b2` | `coroutineScope { urls.map { async }.map { it.await() } }` blocks on slowest hung stream → per-stream `withTimeoutOrNull` so a single bad stream surfaces as status=0 instead of hanging the matrix. |
|
||
|
||
After all of these, expectation is aioquic / picoquic ≥6/7 (M
|
||
might still be flaky). retry green via qlog-driven debugging is
|
||
the marquee result.
|
||
|
||
## Still open
|
||
|
||
- **`v2`** — server demands QUIC v2 (RFC 9369). We're v1-only.
|
||
Implementing v2 is its own project (different Initial-secret
|
||
derivation, different transport-parameter encoding, different
|
||
long-header type bits — not just a version-number swap).
|
||
- **Multiplexing throughput on Mac+Rosetta** — the timeout bump
|
||
unblocks tests that were finishing in time. The deeper fix is
|
||
per-stream backpressure (parser suspends when channel near
|
||
capacity instead of tearing down or dropping). See `:quic`'s
|
||
`Audit-4 #3` decision: prefer fail-fast over silent-drop on
|
||
per-stream channel saturation. Needs a re-think for
|
||
multi-stream-heavy workloads.
|
||
- **Server role** — entire stack is client-only. Implementing the
|
||
server side would unlock `handshakeloss` against aioquic
|
||
(currently `?` because aioquic-server doesn't support it), and
|
||
would make us a self-validating peer.
|
||
|
||
## Concurrency
|
||
|
||
`run-matrix.sh` is NOT safe to run in parallel. The runner's
|
||
docker-compose.yml hardcodes `container_name: sim/server/client` —
|
||
Docker enforces those globally. Use a sequential loop:
|
||
|
||
```
|
||
for peer in aioquic picoquic quic-go; do
|
||
quic/interop/run-matrix.sh -s $peer -t handshake,chacha20,...
|
||
done
|
||
```
|
||
|
||
## Explicitly unsupported testcases (return 127, runner skips)
|
||
|
||
| Testcase | Reason |
|
||
|---|---|
|
||
| `versionnegotiation` | `QuicConnectionWriter` hard-codes `QuicVersion.V1`; needs a configurable initial version + VN-response retry path. **In progress (background agent)**. |
|
||
| `resumption` | session ticket parsing + persistence not yet implemented |
|
||
| `zerortt` | depends on `resumption` + early-data path |
|
||
| `keyupdate` | KEY_PHASE bit handling not yet implemented in 1-RTT |
|
||
| `rebinding-port`, `rebinding-addr` | client-side connection migration (re-bind UDP socket, NEW_CONNECTION_ID rotation) not implemented |
|
||
| `amplificationlimit` | server-side test, N/A for client role |
|
||
| `blackhole` | inverse test (verifies we *fail* on dead network in bounded time); needs special handling |
|
||
| `ipv6` | `UdpSocket` IPv6 path not exercised; risky to claim without testing |
|
||
|
||
## Phase 1a — landed 2026-05-06
|
||
|
||
- `SSLKEYLOGFILE` writer in `InteropClient` (NSS Key Log Format) so Wireshark
|
||
decrypts the sim's pcap captures. Backed by:
|
||
- `TlsClient.clientRandom` (new public read-only property, captured in
|
||
`start()` before sending ClientHello).
|
||
- `QuicConnection.extraSecretsListener` (new optional constructor param,
|
||
chained after the connection's own key-installation listener; no-op
|
||
default, so production callers are unaffected).
|
||
- `chacha20` testcase: forces ChaCha20-Poly1305 only via new
|
||
`QuicConnection.cipherSuites` knob (threaded through `TlsClient` →
|
||
`buildQuicClientHello` → `TlsClientHello`).
|
||
|
||
## Phase 1b — open
|
||
|
||
- `QLOGDIR`: `:quic` has no qlog observer infrastructure yet. Wiring needs
|
||
hooks at packet send/recv, frame dispatch, recovery, and TLS state
|
||
transitions, plus the qlog JSON-NDJSON schema. Sized as its own design
|
||
doc before implementation.
|
||
- `versionnegotiation`: `QuicConnectionWriter` hard-codes `QuicVersion.V1`
|
||
in two call sites; threading a configurable initial-version through and
|
||
wiring the response-handling path is non-trivial. Defer.
|
||
- Server role: we are client-first. Reassess after Phase 3.
|
||
- WebTransport is **not** part of the standard interop matrix; it needs a
|
||
separate harness against `moq-rs` / chrome-headless.
|