Magnetar v1.0.0 closes the permissionless-threshold story at ONE
construction --- THBS-SE (Threshold Hash-Based Signatures with
Selected-Element Reconstruction) --- and removes every legacy
seed-recombine path from the codebase.
The two production primitives at v1.0:
1. Per-validator standalone (standalone.go, unchanged from v0.5.x) ---
the public-BFT primary primitive. Each validator holds its own FIPS
205 keypair, signs independently, consensus collects N signatures
into a ValidatorAggregateCert.
2. THBS-SE (thbsse.go + thbsse_field.go) --- the permissionless
threshold companion. t-of-n committee, slot-bound commit-and-reveal,
PUBLIC COMBINER role (anyone-can-combine, no host in TCB at sign
time), slashable equivocation and malformed-share evidence.
Both emit byte-identical FIPS 205 signatures that unmodified verifiers
accept (TestMagnetar_Wire_FIPS205Verifiable +
TestThbsSE_Wire_FIPS205Verifiable across all 3 SHAKE modes).
Hard invariant (THBS-SE): a revealed value is allowed only if it is
also present in the final SLH-DSA signature. Forbidden reveals:
SK.seed in any party-local persistent form, SK.prf, future-slot share
material. The slot guard refuses any same-slot re-emission.
v1.0 honest open item: the strict "no transient seed at any moment"
invariant requires a v1.1 strict-atom-assembly path
(BLOCKERS.md::MAGNETAR-STRICT-ATOM-V11) that re-implements FIPS 205
sec 5/6/7/8 internally. v1.0 ships a PUBLIC COMBINER that holds the
seed for one slhdsa.SignDeterministic call and zeroizes; materially
stronger than TEE-attested privileged-aggregator constructions,
materially weaker than the strict refinement.
8 test gates + 2 bonus correctness checks:
- TestThbsSE_Wire_FIPS205Verifiable (3 modes) -- byte identity
- TestThbsSE_RejectSeedReveal
- TestThbsSE_RejectUnselectedFORS
- TestThbsSE_RejectUnselectedWOTS
- TestThbsSE_SlotReuseRejected
- TestThbsSE_OverselectedCommittee
- TestThbsSE_SlotBindingDomainSeparation
- BenchmarkThbsSE_Sign_5of7
- TestThbsSE_PublicCombiner_Determinism (bonus)
- TestKAT_ThbsSe (n=7, t=4, 3 modes, 3 messages)
Removed (legacy seed-recombine path + the proofs/CT scaffolding that
modeled it):
- ref/go/pkg/magnetar/{threshold,aggregate,combine,shamir,dkg}.go
+ tests
- ref/go/pkg/magnetar/{e2e,fuzz,n1_byte_equality}_test.go
- ref/go/pkg/thbs/ (entire subtree including dkg2/ PVSS skeleton)
- vectors/{threshold-sign,dkg}.json
- jasmin/{threshold,lib}/ (legacy seed-recombine model)
- proofs/easycrypt/ (entire tree; v1.1 ports to THBS-SE)
- ct/dudect/ (entire tree; v1.1 lands with strict-atom path)
- scripts/{check-lean-bridge,checks/ec-*,checks/jasmin,checks/extraction}.sh
Added:
- ref/go/pkg/magnetar/thbsse.go (1054 LOC; the THBS-SE construction)
- ref/go/pkg/magnetar/thbsse_field.go (GF(257) internal share math)
- ref/go/pkg/magnetar/thbsse_test.go (8 gates + 2 bonus)
- vectors/thbsse-sign.json (deterministic (n=7,t=4) KAT)
- v1.0 supersede notices on v0.x archival docs
Verification:
- GOWORK=off go build ./... && go vet ./...: clean
- go test -count=1 -short: PASS (all gates)
- go test -count=1 -race -short: PASS
- grep "reveal-and-aggregate|seed.*recombin|THBS over.*seed|aggregator.*reconstruct.*seed" *.go: 0 matches
- find ref/go/pkg -type d -name thbs: empty
Jasmin scaffolding for the Magnetar high-assurance track, mirroring
Pulsar's structure but specialized to SLH-DSA-SHAKE-192s. Surface area:
lib/ — shared protocol primitives:
magnetar_params.jinc — Shamir prime, seed size, quorum cap,
wire-format constants
lagrange_gf257.jinc — byte-wise Lagrange coefficient computation
over GF(257); constant-time over (public)
eval-point set
transcript.jinc — cSHAKE256 absorption primitives with the
MAGNETAR-*-V1 customisation tags
seed.jinc — pack_bytesum_be: byteSum vector → big-
endian byte string for the
MAGNETAR-SEED-SHARE-V1 mix
threshold/ — protocol-layer .jazz files:
round1.jazz — per-party Round-1 commit (mask derive,
share mask, D_i digest)
round2.jazz — per-party Round-2 reveal (mask || masked)
combine.jazz — aggregator: commit re-derive, Lagrange
reconstruct, mix-to-seed, SLH-DSA dispatch
slh-dsa/ — single-party reference (libjade-SLH-DSA when upstream
lands; today routes through cloudflare/circl). README +
fetch.sh skeleton.
Structural simplification: ~600 LOC vs Pulsar's ~1500 LOC. The
elimination comes from byte-wise Z_257 arithmetic (no Montgomery,
no NTT, no polynomial vectors), no rejection-loop kappa state, and
the monolithic SLH-DSA signature output (no FIPS 204 §3.5.5
c_tilde/z/h decomposition).
The .jazz files type-check under jasminc -until_typing and target
jasmin-ct clean. The CI gate scripts/checks/jasmin.sh is skip-
friendly if jasminc is not on PATH.
Lux Magnetar