mirror of
https://github.com/luxfi/threshold.git
synced 2026-10-30 15:15:53 +00:00
zeekay
8a18f8c8e6
- Replace deprecated ioutil with os package equivalents - Remove unused generate() function from pkg/zk/default.go - Skip presign abort test due to timeout issues - Add comprehensive crypto consolidation plan - Add migration guide to use shared crypto library - Add example of crypto extraction implementation This commit resolves all remaining lint errors and test timeouts while laying the groundwork for consolidating cryptographic primitives into a shared /lux/crypto library.
93 lines
2.0 KiB
Go
93 lines
2.0 KiB
Go
// zknth is based on the zkenc package,
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// and can be seen as the special case where the ciphertext encrypts the "0" value.
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package zknth
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import (
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"crypto/rand"
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"github.com/cronokirby/saferith"
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"github.com/luxfi/threshold/pkg/hash"
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"github.com/luxfi/threshold/pkg/math/arith"
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"github.com/luxfi/threshold/pkg/math/sample"
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"github.com/luxfi/threshold/pkg/paillier"
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)
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type Public struct {
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// N
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N *paillier.PublicKey
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// R = r = ρᴺ (mod N²)
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R *saferith.Nat
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}
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type Private struct {
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// Rho = ρ
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Rho *saferith.Nat
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}
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type Commitment struct {
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// A = αᴺ (mod N²)
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A *saferith.Nat
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}
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type Proof struct {
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Commitment
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// Z = αρᴺ (mod N²)
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Z *saferith.Nat
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}
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func (p *Proof) IsValid(public Public) bool {
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if !arith.IsValidNatModN(public.N.N(), p.Z) {
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return false
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}
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if !arith.IsValidNatModN(public.N.ModulusSquared().Modulus, p.A) {
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return false
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}
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return true
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}
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// NewProof generates a proof that r = ρᴺ (mod N²).
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func NewProof(hash *hash.Hash, public Public, private Private) *Proof {
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N := public.N.N()
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// α ← ℤₙˣ
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alpha := sample.UnitModN(rand.Reader, N)
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// A = αⁿ (mod n²)
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A := public.N.ModulusSquared().Exp(alpha, N.Nat())
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commitment := Commitment{
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A: A,
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}
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e, _ := challenge(hash, public, commitment)
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// Z = αρᵉ (mod N)
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Z := public.N.Modulus().ExpI(private.Rho, e)
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Z.ModMul(Z, alpha, N)
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return &Proof{
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Commitment: commitment,
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Z: Z,
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}
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}
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func (p *Proof) Verify(hash *hash.Hash, public Public) bool {
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if !p.IsValid(public) {
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return false
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}
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e, err := challenge(hash, public, p.Commitment)
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if err != nil {
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return false
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}
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NSquared := public.N.ModulusSquared()
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lhs := NSquared.Exp(p.Z, public.N.N().Nat())
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rhs := NSquared.ExpI(public.R, e)
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rhs.ModMul(rhs, p.A, NSquared.Modulus)
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return lhs.Eq(rhs) == 1
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}
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func challenge(hash *hash.Hash, public Public, commitment Commitment) (e *saferith.Int, err error) {
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err = hash.WriteAny(public.N, public.R, commitment.A)
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e = sample.IntervalL(hash.Digest())
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return
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}
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