`Proofs/SigApexSpec.lean`:
- `verify_loop_full` — the extracted 32-byte comparison loop returns exactly
the byte-equality of the two arrays (induction; axiom cone = exactly
[propext, Classical.choice, Quot.sound]).
- `verify_accepts_iff` — THE APEX: for a signature that parses, the
extracted RustCrypto verifier accepts IFF the recomputed compressed point
compress( [s]·B − [k]·A )
equals the signature's R byte-for-byte. The recomputation is grounded in
the PROVEN curve model (every curve and scalar call is a certified
definition); k is whatever scalar the SHA-512 oracle produces — the
honest EdDSA acceptance criterion with the hash opaque.
Boundary hygiene forced by the audit itself:
- The public vartime_double_scalar_mul_basepoint dispatch pulled the AVX2
vector-backend axiom into the apex cone. Fixed at the build level:
extract.sh pins RUSTFLAGS --cfg curve25519_dalek_backend="serial", so the
SIMD arm compiles out; BackendKind has only Serial and
get_selected_backend becomes a real definition (ok Serial).
- subtle.Choice.unwrap_u8 upgraded from axiom to the documented model
definition (Choice := U8; unwrap_u8 = self.0) — it sits on the verify
path via compress → is_negative.
- CurveSig modules added to GEN_MODULES (stale-olean incoherence otherwise).
check.sh grows Phase 3b: the apex certificate's axiom cone must equal
EXACTLY
[propext, Classical.choice, Quot.sound,
ed25519.Signature, sha2.Sha512,
sha512_new, sha512_update, sha512_finalize_bytes,
ed25519.Signature.to_bytes, signature.error.Error, Error.new]
— the SHA-512 hash oracle plus the opaque wire-format types. NO curve
axioms, NO scalar axioms, NO backend axioms, enforced on every button press.
Full check.sh green: 16 standard certificates + the apex audit.
Phase 2 (the point-level equation [s]B − [k]A = decompress R, needing
to_bytes canonicity and decompress) remains deferred and documented.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
The complete non_adjacent_form(5) verification (four stages):
- `Proofs/DsmNafLoadSpec.lean` (generated) — the LE byte-to-word load.
- `Proofs/DsmNafMath.lean` — the digit loop's arithmetic core: window-read
lemmas (single/cross-word), the exact ZZ invariant steps (Nat.mod_mul
telescope), the carry-kill argument from V < 2^253, and the exit theorem.
- `Proofs/DsmNafLoopSpec.lean` — the w=5 digit loop by induction on the
remaining-bits measure: per-step 64-bit window read (4-way word split),
digit write via hcast/wrapping_sub (exact value window - 32*carry',
oddness, |d| < 16), invariant carried through even/odd steps.
- `Proofs/DsmNafSpec.lean` — the public spec: both entry masserts
DISCHARGED; the digits satisfy the NAF conditions and
sum naf[k]*2^k = V EXACTLY (integers, no modular slack)
for any scalar whose LE byte value V is below 2^253.
And the campaign's brick 4, `Proofs/DsmMulSpec.lean`:
- `run_basepoint` — the transpiled ED25519_BASEPOINT_POINT is the standard
base point: valid extended coordinates (X*Y = Z*T) and the curve equation,
kernel-checked via denominator-free 121666-scaled witnesses. Includes the
generic witness lemmas fp_mul_eq_of_witness / onCurve_of_witness.
- `vartime_double_base_mul_spec` — THE PHASE-1 COMPUTATIONAL SPEC of
vartime_double_base::mul: for canonical scalars and a valid on-curve A,
the result is valid, on-curve, and denotes
dsmFold (naf a) (naf b) (edPt A) edBasePt edId 256
with both digit arrays proven exact NAF encodings. Phase 2 (group
semantics [a]A + [b]B) requires Edwards associativity — deferred and
documented; nothing assumes it.
Also: removed a vestigial pre-re-extraction axiom stub
(backend.serial.scalar_mul.vartime_double_base.mul) from FunsExternal —
a root-level leftover that shadowed the real namespaced definition during
name resolution in proof files. Never referenced by any certificate (the
#print-axioms audit guards against that); deleted for hygiene.
CERTS += naf_load_spec, naf_exit, naf_digit_loop_spec,
non_adjacent_form_spec, run_basepoint, vartime_double_base_mul_spec —
each audited to exactly [propext, Classical.choice, Quot.sound].
Full check.sh green.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Ported from the locally verified Hermes working copy; FeQ and Square2Spec
(dead files in the published replica) now compile and are in the check
manifest. check.sh gates: source integrity, stub audit, zero axiom
declarations under Proofs/, per-certificate axiom audit.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
