Pure refactors for the Charon/Aeneas extraction pipeline; production
behavior unchanged (both default and pinned configs cargo-check clean,
pre-existing warnings only).
- ed_sigs::sha512_hash3: single-call SHA-512 oracle, semantically
Sha512(r || a || m); a monomorphic signature with no foreign types lets
the extractor treat the hash as one opaque oracle (sha2-0.11 stack).
- VerificationKey::verify_sha512 (+ recompute_r_sha512, a_bytes_nonzero,
check_scalar_canonical, is_legacy_excluded_r): semantically identical
to verify_dalek with each step spelled extractor-friendly - derived
array PartialEq/contains as explicit index loops, and
Scalar::from_canonical_bytes (subtle internals defeat the extractor)
as an explicit s < l byte compare + from_bytes_mod_order (the identity
on canonical bytes). Signature accessors each called exactly once.
- SIMD gates: cfg(target_arch = "x86_64") becomes
cfg(all(target_arch = "x86_64", not(curve25519_serial_only))). Default
builds are identical (the new cfg is never set); extraction builds pass
RUSTFLAGS=--cfg curve25519_serial_only so the AVX2 dispatch arm
compiles out and backend selection is the real constant Serial - the
same serial-pin mechanism upstream curve25519-dalek provides natively.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* remove README.md in the syscall directory
* use workspace dependency in `bls12-381`
* add `workspace.package` information
* use 2021 edition for bls12-381
* inherit workspace.package for `ed25519-pokos`
* cargo fmt
