Critical interop blockers + security/correctness gaps surfaced by the
parallel round-4 audit. All fixes have inline comments referencing the
audit finding number.
Frame layer:
* Decode RESET_STREAM (0x04), STOP_SENDING (0x05), NEW_TOKEN (0x07).
Pre-fix these fell through to the `unknown frame type` branch and
threw QuicCodecException through the read loop, killing the
connection. aioquic and picoquic emit RESET_STREAM regularly.
* Wrap decodeFrames in try/catch in dispatchFrames; on a decode
error, transition to CLOSED gracefully via markClosedExternally
instead of letting the exception escape the read loop.
Connection layer:
* Reject peer-attempted CLIENT_BIDI / CLIENT_UNI stream IDs that don't
map to a stream we opened (RFC 9000 §19.8 STREAM_STATE_ERROR).
* MaxDataFrame now actually updates sendConnectionFlowCredit (was a
no-op pre-fix; sustained sends silently stalled).
* Writer enforces sendConnectionFlowCredit and tracks
sendConnectionFlowConsumed so cumulative bytes stay under the
peer's initial_max_data cap.
* SERVER_BIDI peer-opened streams inherit sendCredit from
peer.initialMaxStreamDataBidiLocal (was 0L; reply path was wedged
until MAX_STREAM_DATA arrived).
* applyPeerTransportParameters validates initial_source_connection_id
and original_destination_connection_id (RFC 9000 §7.3 MUST checks);
mismatch closes with TRANSPORT_PARAMETER_ERROR.
* Cap incomingDatagrams queue at 256 (audio rooms ~50/sec; 5-second
burst). On overflow, drop oldest — fresh frames matter more for
live media. Pre-fix RFC 9221 datagrams were unbounded.
Stream layer:
* QuicStream.deliverIncoming now returns Boolean; parser closes the
connection with INTERNAL_ERROR on saturation rather than silently
dropping bytes (peer believes the bytes were delivered, application
sees a hole).
* ReceiveBuffer tracks finOffset and exposes isFullyRead(); parser
only closes the incoming channel after the contiguous read frontier
reaches the FIN offset (pre-fix closing on FIN-frame arrival
truncated streams that had gaps).
TLS hardening:
* certificateValidator is non-null. Tests pass an explicit
PermissiveCertificateValidator; null was a silent-MITM hazard.
* Drop SIG_RSA_PKCS1_SHA256 from accepted CertificateVerify
schemes (forbidden by RFC 8446 §4.2.3 in CertificateVerify).
* Hard-fail the PSK-Finished path: we never offer a pre_shared_key
extension, so a server skipping Certificate/CertificateVerify is
either misbehaving or a partial-MITM stripping cert proof.
* Validate ALPN: reject any ALPN the server selected that we didn't
offer (was previously accepted silently).
* Add APPLICATION-level inboundBuffer so post-handshake CRYPTO
(NewSessionTicket, KeyUpdate detection) reaches the
SENT_CLIENT_FINISHED handler.
* State.FAILED is now actually assigned on any handler throw;
pushHandshakeBytes refuses further bytes when in FAILED.
* IP-literal precheck before InetAddress.getByName so cert
validation doesn't trigger DNS A/AAAA lookups for hostnames
(audit-4 #4: leaked SNI/hostname over plaintext DNS).
WT layer:
* GOAWAY id-regression check (RFC 9114 §5.2: MUST NOT increase).
A server sending an increasing id raises QuicCodecException.
* WT_CLOSE_SESSION decoder rejects bodies < 4 bytes (mandatory
error-code field) and reasons > 8192 bytes.
* Capsule reader catches Throwable but separately rethrows
CancellationException; on parse error, completes peerCloseDeferred
exceptionally so awaitPeerClose() doesn't hang forever.
HTTP/3 + QPACK:
* Http3Settings.decodeBody rejects duplicate ids (RFC 9114 §7.2.4.1
H3_SETTINGS_ERROR).
* QpackInteger.decode bounds-checks shift before extending value;
defence-in-depth Long-overflow check on accumulated value.
* QpackDecoder static-table accesses go through a bounds-checking
helper that throws typed QuicCodecException; literal lengths are
range-checked before allocation.
Test infra:
* InMemoryQuicPipe accepts an injectable serverScid and constructs
its tlsServer with TPs that include the required CIDs.
* InProcessTlsServer emits stub Certificate + CertificateVerify
so the real (non-PSK) handshake path is exercised.
* Updated all test callers to use PermissiveCertificateValidator.
* Updated CapsuleReaderTest with negative-path assertions for the
new strictness.
https://claude.ai/code/session_01EC1tfXfap8k8GyKvrxkxZx
Claude
222a4e7d42