Files
threshold/protocols/rlwe-tee/envelope.go
zeekay f6093e719b protocols/rlwe-tee: institutional-custody Ring-LWE via TEE-gated trusted-dealer reconstruction
Sibling of protocols/{slhdsa,mldsa}-tee for the corona Ring-LWE
primitive. Master trusted-dealer key (32 B, sign.KeySize) lives
sealed-at-rest in hsm.Provider; per-Sign the TEE attestation
authorizes release and then the dealer's GenerateKeys + the n-party
Round1 / Round2 / Finalize all run inside the attested process.

Composition (not inheritance):
  Signer { gate kms.ReleaseGate; hsmP hsm.Provider;
           appr approval.ApprovalProvider; cfg Config }

corona.threshold.GenerateKeys writes package-level globals
(sign.K, sign.Threshold) — coronaSerializer wraps every entry point
into corona so two concurrent Signers on the same process do not race
through that shared state. Workaround for an upstream constraint; not
a security boundary.

Permissionless path (corona.keyera.BootstrapPedersen — no party ever
holds the master) UNAFFECTED. This is the opt-in institutional-
custody extension. Use cases: foundation HSM ceremonies, single-
operator bridge custody.

11 tests + 9 Config sub-tests; t.Parallel; depends on luxfi/corona
v0.7.6 (canonical Signature/GroupKey/VerifyBytes wire codec).
2026-06-01 12:18:07 -07:00

83 lines
2.3 KiB
Go

// SPDX-License-Identifier: BSD-3-Clause
package rlwetee
import (
"context"
"crypto/sha256"
"crypto/subtle"
"errors"
"fmt"
"github.com/luxfi/mpc/cc/attest"
"github.com/luxfi/mpc/pkg/kms"
)
// Envelope is the minimal kms.CompositeAttestation implementation
// consumed by this package. Mirrors slhdsa-tee.Envelope so embedders
// that compose multiple primitives share the same plumbing.
type Envelope struct {
Kind attest.Kind
EvidenceBytes []byte
ExpectedNonce [32]byte
RIM [32]byte
Hardware [32]byte
TEEPub [32]byte
VerifyOpts []attest.Option
}
var _ kms.CompositeAttestation = (*Envelope)(nil)
// Verify implements kms.CompositeAttestation.Verify.
func (e *Envelope) Verify(expectedNonce [32]byte) (bool, error) {
if subtle.ConstantTimeCompare(e.ExpectedNonce[:], expectedNonce[:]) != 1 {
return false, nil
}
return true, nil
}
// VerifyEvidence implements kms.CompositeAttestation.VerifyEvidence.
func (e *Envelope) VerifyEvidence(ctx context.Context, opts ...attest.Option) ([]*attest.VerifiedReport, error) {
if len(e.EvidenceBytes) == 0 {
return nil, fmt.Errorf("%w: empty evidence", attest.ErrInvalidEvidence)
}
allOpts := append([]attest.Option{}, e.VerifyOpts...)
allOpts = append(allOpts, opts...)
rep, err := attest.Dispatch(ctx, e.Kind, e.EvidenceBytes, allOpts...)
if err != nil {
return nil, err
}
if err := defaultRIMCheck(rep, e.RIM); err != nil {
return nil, err
}
return []*attest.VerifiedReport{rep}, nil
}
func (e *Envelope) RIMDigest() [32]byte { return e.RIM }
func (e *Envelope) HardwareFingerprint() [32]byte { return e.Hardware }
func (e *Envelope) TEEPublicKey() [32]byte { return e.TEEPub }
func (e *Envelope) EvidenceIssuers() []string {
switch e.Kind {
case attest.KindSEVSNP:
return []string{kms.IssuerSEVSNP}
case attest.KindTDX:
return []string{kms.IssuerTDX}
case attest.KindNRAS:
return []string{kms.IssuerNVNRAS}
default:
return nil
}
}
func defaultRIMCheck(rep *attest.VerifiedReport, expected [32]byte) error {
if rep == nil {
return errors.New("rlwe-tee: defaultRIMCheck: nil verified report")
}
got := sha256.Sum256(rep.Measurement)
if subtle.ConstantTimeCompare(got[:], expected[:]) != 1 {
return fmt.Errorf("%w: report measurement does not fold to operator-asserted RIM", attest.ErrPolicy)
}
return nil
}