init: v1.0.0

2026-05-27 23:03:00 +08:00
commit 8d97f750eb
466 changed files with 80067 additions and 0 deletions
@@ -0,0 +1,113 @@
+package dkgc
+
+import (
+	"crypto/rand"
+	"io"
+	"math/big"
+
+	"xdx.jelly/xgcl/sm/sm9"
+)
+
+type DoubleKGC struct {
+	ks         sm9.MastSignPrivateKey
+	commonPubs sm9.MastSignPublicKey
+}
+
+func (dk *DoubleKGC) GenerateMastKey() {
+
+}
+
+var alpha = big.NewInt(2)
+var alphaInv = new(big.Int).ModInverse(alpha, sm9.Order())
+
+func ComputeHHat(id []byte) (*big.Int, *big.Int, bool) {
+	h1 := sm9.H1(id, []byte{0x01})
+	hh := new(big.Int).ModSqrt(h1, sm9.Order())
+	if hh == nil {
+		hh = new(big.Int).Lsh(h1, 1)
+		hh.ModSqrt(hh, sm9.Order())
+		return h1, hh, false
+	}
+	return h1, hh, true
+}
+
+func UserRandom0(reader io.Reader, basePoint *sm9.G1) (*big.Int, *sm9.G1, error) {
+	r, err := rand.Int(reader, sm9.Order())
+	if err != nil || r.Sign() == 0 {
+		return nil, nil, err
+	}
+	R := &sm9.G1{}
+	R.ScalarMult(basePoint, r)
+	return r, R, nil
+}
+
+func KGC1ComputeData(reader io.Reader, R *sm9.G1, ks *sm9.MastSignPrivateKey, hh *big.Int) (*big.Int, *sm9.G1, error) {
+	r, err := rand.Int(reader, sm9.Order())
+	if err != nil {
+		return nil, nil, err
+	}
+
+	t1 := new(big.Int).Add(hh, &ks.Int)
+	t1.Mod(t1, sm9.Order())
+	if t1.Sign() == 0 {
+		panic("Got zero of t1")
+	}
+	t1.ModInverse(t1, sm9.Order())
+	t1.Mul(t1, r)
+	t1.Mod(t1, sm9.Order())
+
+	r.ModInverse(r, sm9.Order())
+	T1 := new(sm9.G1).ScalarMult(R, r)
+	return t1, T1, nil
+}
+
+func KGC2ComputeData(T1 *sm9.G1, ks *sm9.MastSignPrivateKey, hh *big.Int) (*sm9.G1, error) {
+	t2 := new(big.Int).Add(hh, &ks.Int)
+	t2.ModInverse(t2, sm9.Order())
+	T2 := new(sm9.G1).ScalarMult(T1, t2)
+	return T2, nil
+}
+
+func UserComputeSignKey(id []byte, t1 *big.Int, T2 *sm9.G1, r *big.Int, pubs1, pubs2, pubs *sm9.MastSignPublicKey, basePoint *sm9.G1) (*sm9.UserSignKey, *sm9.MastSignPublicKey, error) {
+	h1, hh, isSquare := ComputeHHat(id)
+	rInv := new(big.Int).ModInverse(r, sm9.Order())
+	if isSquare {
+		// h1 is square
+		d := new(big.Int).Mul(h1, t1)
+		d.Mul(d, rInv)
+		d.Mod(d, sm9.Order())
+		ds := new(sm9.G1).ScalarMult(T2, d)
+		ds.Neg(ds)
+		// ds.Add(ds, sm9.G1Generator())
+		ds.Add(ds, basePoint)
+
+		g := new(sm9.G2).Add(&pubs1.G2, &pubs2.G2)
+		g.ScalarMult(g, hh)
+		g.Add(g, &pubs.G2)
+		return &sm9.UserSignKey{
+				G1: *ds,
+			}, &sm9.MastSignPublicKey{
+				G2: *g,
+			}, nil
+	} else {
+		d := new(big.Int).Mul(h1, t1)
+		d.Mul(d, rInv)
+		d.Mul(d, alpha)
+		d.Mod(d, sm9.Order())
+
+		ds := new(sm9.G1).ScalarMult(T2, d)
+		ds.Neg(ds)
+		// ds.Add(ds, sm9.G1Generator())
+		ds.Add(ds, basePoint)
+
+		g := new(sm9.G2).Add(&pubs1.G2, &pubs2.G2)
+		g.ScalarMult(g, hh)
+		g.ScalarMult(g, alphaInv)
+		g.Add(g, new(sm9.G2).ScalarMult(&pubs.G2, alphaInv))
+		return &sm9.UserSignKey{
+				G1: *ds,
+			}, &sm9.MastSignPublicKey{
+				G2: *g,
+			}, nil
+	}
+}