nx_kyber_poly_wasm.nx

nx_kyber_poly_wasm.nx -- K-PKE polynomial helpers for FIPS 203 ML-KEM-768. Composes with the shipped nx_kyber_ntt (L117). Together these are the L2 substrate transforms that nx_ml_kem_768.nx (L118 next) composes the FIPS 203 KEM around. All polynomials are 256-coefficient over Z_{3329}. In-memory format: packed little-endian INT16 at byte ptr (512 bytes per polynomial). CALLER is responsible for canonical-form vs Montgomery-form bookkeeping per FIPS 203 conventions (NTT-domain polynomials are in Mont form per PQClean `_tomont`; canonical-form polynomials are NOT). Public API: nx_kyber_poly_add(out, a, b) -> i64 out = a + b mod q nx_kyber_poly_sub(out, a, b) -> i64 out = a - b mod q nx_kyber_poly_cbd_eta2(out, buf) -> i64 centered binomial sample from 128 bytes nx_kyber_poly_compress10(bytes_out, poly) -> i64 320-byte d_u packing nx_kyber_poly_decompress10(poly, bytes) -> i64 320-byte unpack nx_kyber_poly_compress4(bytes_out, poly) -> i64 128-byte d_v packing nx_kyber_poly_decompress4(poly, bytes) -> i64 128-byte unpack nx_kyber_poly_tobytes12(bytes_out, poly) -> i64 384-byte canonical nx_kyber_poly_frombytes12(poly, bytes) -> i64 384-byte parse Reductions: caller-provided polynomials should be in canonical [0, q). poly_add/sub output coefficients in [0, 2q-2] / [-q+1, q-1]; caller applies barrett_reduce (in NTT module) before passing further if needed. Verified: smoke runs each compress/decompress pair + tobytes/frombytes round-trip; the deterministic encoding round-trips bit-exact. license_tier: INDEPENDENT_REDERIVE genealogy_id: international-research-sources/nist/fips_203 lineage_id: nishi_kyber_poly_wasm_q1 safe_shift_audit: no 64-bit rotations in this module