da3e77d33e
Add the canonical RFC 9001 Appendix A.2 client Initial packet — the single
most diagnostic interop vector in the QUIC spec. The full 1200-byte
protected datagram decrypts bit-for-bit to the published 245-byte CRYPTO
frame plus 917 bytes of PADDING, using the canonical client_initial keys
derived from DCID 8394c8f03e515708.
The test verifies:
- parseAndDecrypt succeeds against the canonical client_initial keys.
- Header fields: INITIAL type, version 1, packet number 2,
DCID = 8394c8f03e515708, zero-length SCID, empty token.
- Plaintext payload size = 1162 bytes (1182 length field - 4 PN - 16 tag).
- First 245 bytes of plaintext == published unprotected payload byte-for-byte.
- Remaining 917 bytes are all PADDING (0x00).
- Frame decoder picks the leading CRYPTO frame at offset 0.
- First byte of CRYPTO body is TLS ClientHello (0x01).
This proves end-to-end that header protection unmask, AEAD-GCM decrypt,
packet-number reconstruction, and frame parsing all line up with the
canonical Cloudflare reference implementation. Combined with the §A.5
ChaCha20 vector and §A.1 Initial-secret derivation, every packet-protection
path our minimal client uses is now bit-verified against the IETF RFC.
https://claude.ai/code/session_01EC1tfXfap8k8GyKvrxkxZx