Implement a TLS 1.3 client state machine that drives the QUIC handshake using
only Quartz's existing crypto. No BouncyCastle dependency.
- HKDF-Expand and HKDF-Expand-Label upstreamed to Quartz's Hkdf class with
RFC 5869 + RFC 8448 test vectors covering them.
- :quic crypto stack: AEAD (AES-128-GCM via Quartz's AESGCM, ChaCha20-Poly1305
via Quartz's pure-Kotlin impl), header protection (AES-ECB via JCA single
block + ChaCha20 keystream), QUIC Initial-secret derivation matching
RFC 9001 Appendix A.1 bit-for-bit.
- TLS 1.3 transcript hash, key schedule (early/handshake/master + per-direction
client/server traffic secrets), Finished MAC.
- ClientHello + extension encoders carrying SNI, supported_versions=[TLS 1.3],
supported_groups=[X25519], signature_algorithms covering ECDSA/RSA-PSS/Ed25519,
X25519 key_share, psk_dhe_ke, ALPN=[h3], and the QUIC transport_parameters
extension.
- ServerHello + EncryptedExtensions + Certificate + CertificateVerify + Finished
parsers. The state machine handles the certificate path and the PSK-style
no-cert path; certificate validation is wired through a CertificateValidator
SPI (real impl lands in Phase L).
- Transport parameters codec covering all RFC 9000 §18.2 + RFC 9221 fields.
- QuicWriter/QuicReader buffer helpers shared across the rest of the stack.
Round-trip test: a minimal in-process TLS server built from the same primitives
drives a full ClientHello → ServerHello → EE → Finished → client Finished
exchange. Both sides reach handshake-complete and agree bit-for-bit on the
handshake & application traffic secrets. ALPN + transport parameters round-trip
through EncryptedExtensions cleanly.
https://claude.ai/code/session_01EC1tfXfap8k8GyKvrxkxZx
Create the new :quic Gradle module (KMP, api(project(":quartz"))) and migrate
the QUIC varint codec out of :nestsClient where it was incidentally living.
Add the connection-ID, packet-number-space, and UDP socket primitives that
the rest of the QUIC client will build on.
Layer-by-layer plan in docs/plans/2026-04-22-pure-kotlin-quic-webtransport-plan.md.
- New :quic module wired into settings.gradle, with commonMain + jvmAndroid
source sets mirroring :quartz's structure.
- Varint moves from com.vitorpamplona.nestsclient.moq to com.vitorpamplona.quic;
MoqBuffer/MoqCodec updated to import the new path.
- ConnectionId enforces the 0..20 byte length range and ships a randomizer
backed by Quartz's RandomInstance.
- PacketNumberSpaceState tracks per-space outbound allocation + largest-received
tracking, and implements the RFC 9000 §A.3 truncated-PN decode formula plus
the §17.1 minimum encode-length picker.
- UdpSocket is an expect class with a connected DatagramChannel actual on
jvmAndroid using Dispatchers.IO (no Selector — one socket per connection).
All 12 tests pass on jvmTest. RFC 9000 §A.1 varint vectors and §A.3 truncated-PN
vector match bit-for-bit.
https://claude.ai/code/session_01EC1tfXfap8k8GyKvrxkxZx
Claude