writeonce/docs/stories/runtime-v2
shoney.arickathil 3b1a188d77 fix(crypto): branch-free EC signing ladder via complete addition (rv2 9 follow-up)
- pmul_ct: double-and-add-always over the Renes–Costello–Batina complete
  projective addition formula (Alg. 4, a=-3) — one exception-free formula for
  add and double, identity (0:1:0), so there is NO point-at-infinity branch.
  Closes the documented residual: the Jacobian jadd/jdouble ladder's fp_zero
  checks leaked k's leading-zero count (a bit-length hint) during ECDSA sign
- wo_ecdsa_p256_sha256_sign uses it; affine x = X * Z^-1 (projective), the
  inversion via the constant-time modexp. Dead Jacobian jmul_ct/jpt_cmov removed
- RFC 6979 A.2.5 vectors still byte-exact (test_crypto 130/0); server loopback
  (signs with this ladder) still green (test_tls 123/0); ASan/UBSan clean
- docs: rv2 9 review_pending — close_notify + complete-formula ladder moved
  from deferred to landed; lang-41 decision 4 fixture marked landed

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
(cherry picked from commit fba30352b965e0f3b749168421a920a832df541b)
2026-09-15 01:16:13 +02:00
..
00-story.md docs: jarvis track, runtime-v2 7/8/9, lang-41 fix design, fiber scope-gap 2026-09-15 01:15:31 +02:00
01-streaming-subprocess.md docs(rt2): close out runtime-v2 1-5 2026-09-15 01:15:30 +02:00
02-pty.md docs(rt2): close out runtime-v2 1-5 2026-09-15 01:15:30 +02:00
03-signals-as-events.md docs(rt2): close out runtime-v2 1-5 2026-09-15 01:15:30 +02:00
04-termios.md docs(rt2): close out runtime-v2 1-5 2026-09-15 01:15:30 +02:00
05-fd-passing.md docs(rt2): close out runtime-v2 1-5 2026-09-15 01:15:30 +02:00
06-term-size-width.md feat(rt2): term.size + term.width — the wmux ladder's last runtime asks 2026-09-15 01:15:30 +02:00
07-observability.md docs(audit): fix stale docs against the code (TLS, net.connect, RNG, lang-41); jarvis deps 2026-09-15 01:16:13 +02:00
08-symmetric-cipher.md docs(rv2-aead): rv2 8 phase C (software AES-GCM fallback) landed 2026-09-15 01:15:31 +02:00
09-in-process-tls.md fix(crypto): branch-free EC signing ladder via complete addition (rv2 9 follow-up) 2026-09-15 01:16:13 +02:00