- wo_tls_client: a pure state machine (no sockets). Caller frames
records; driver runs ClientHello->ServerHello->flight->Finished and
hands back bytes to send. Keeps all I/O out of the security-critical FSM
- start_with (inject CH + ephemeral priv), push_record, take_output,
encrypt/decrypt (application traffic keys). Handshake-message reassembly
across records; per-message transcript timing (CertVerify signs CH..Cert,
Finished MACs CH..CertVerify); constant-time Finished compare; every
failure lands in FAILED (no warn-and-continue)
- verifies server CertificateVerify (phase E+D) + server Finished, emits
the client Finished, switches to application keys
- KAT: whole handshake driven offline against the RFC 8448 record trace —
client Finished record byte-for-byte, first client app record
byte-for-byte, NewSessionTicket + server app data decrypt to plaintext,
tampered flight -> FAILED. test_tls 90 pass, ASan/UBSan clean
- SECURITY TODO before live use (documented in tls.h + story): chain walk
to a trust anchor + SAN/hostname match; random ephemeral for production
start; the net.connect_tls socket glue
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
(cherry picked from commit 74c332d7efdb8bbfdbe90bd2fcc3defa2fe8da00)