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 +1,134 @@
+package outsource
+
+import (
+	"crypto/rand"
+	"errors"
+	"io"
+	"math/big"
+
+	"xdx.jelly/xgcl/gmath"
+	"xdx.jelly/xgcl/he/paillier"
+	"xdx.jelly/xgcl/sm/sm2"
+)
+
+// 客户端加密clientKey^{-1}给外包服务器保存，用作同态解密密钥
+func EncryptClientDecKey(clientKey *sm2.PrivateKey, k *paillier.PublicKey, rnd io.Reader) (*paillier.Cipher, error) {
+	d := clientKey.D
+	di := new(big.Int).ModInverse(d, sm2.OrderN())
+	return k.Encrypt(di, rnd)
+}
+
+type ClientKeyGenerator struct {
+	dc1, dc1Inv *big.Int
+}
+
+// NewClientKeyGen 客户端第一步
+// 返回数据发送给OS服务端
+func (c *ClientKeyGenerator) Step1(k *paillier.PublicKey, rnd io.Reader) (*paillier.Cipher, *paillier.Cipher, error) {
+	var d *big.Int
+	var err error
+	for {
+		d, err = rand.Int(rnd, sm2.OrderN())
+		if err != nil {
+			return nil, nil, err
+		}
+		if d.Sign() > 0 {
+			break
+		}
+	}
+	di := new(big.Int).ModInverse(d, sm2.OrderN())
+	c.dc1 = d
+	c.dc1Inv = di
+
+	a1, err := k.Encrypt(d, rnd)
+	if err != nil {
+		return nil, nil, err
+	}
+	a2, err := k.Encrypt(di, rnd)
+	if err != nil {
+		return nil, nil, err
+	}
+	return a1, a2, nil
+
+}
+
+// GenerateDataToServer 客户端第二步
+// 返回的sm2.PublicKey发送给协同签名服务端。
+func (c *ClientKeyGenerator) Step2(P *sm2.PublicKey) (*sm2.PublicKey, error) {
+	x, y := sm2.Curve256.ScalarMult(P.X, P.Y, c.dc1Inv.Bytes())
+	return &sm2.PublicKey{Curve: sm2.Curve(), X: x, Y: y}, nil
+}
+
+// GenerateDataToServer 客户端第三步
+// 收到协同签名服务端返回数据
+func (c *ClientKeyGenerator) Step3(R *sm2.PublicKey) (*sm2.PublicKey, error) {
+	x, y := sm2.Curve256.ScalarMult(R.X, R.Y, c.dc1Inv.Bytes())
+	return &sm2.PublicKey{Curve: sm2.Curve(), X: x, Y: y}, nil
+}
+
+// GenerateDataToServer 客户端第四步
+// 收到协同签名服务端返回数据
+func (c *ClientKeyGenerator) Step4(T1 *sm2.PublicKey) (*sm2.PublicKey, error) {
+	x, y := sm2.Curve256.ScalarMult(T1.X, T1.Y, c.dc1Inv.Bytes())
+	x, y = sm2.Curve256.Add(x, y, nGx, nGy)
+	return &sm2.PublicKey{Curve: sm2.Curve(), X: x, Y: y}, nil
+}
+
+// OS服务端
+type OSKeyGenerator struct {
+	dc2, dc2Inv *big.Int
+}
+
+func (o *OSKeyGenerator) Marshal() ([]byte, error) {
+	data := make([]byte, 64)
+	if o.dc2 != nil {
+		gmath.FillBytes(o.dc2, data)
+	}
+
+	if o.dc2Inv != nil {
+		gmath.FillBytes(o.dc2, data[32:])
+	}
+
+	return data, nil
+}
+
+func (o *OSKeyGenerator) Unmarshal(b []byte) error {
+	if len(b) < 64 {
+		return errors.New("input too short")
+	}
+	o.dc2 = new(big.Int).SetBytes(b[:32])
+	o.dc2Inv = new(big.Int).SetBytes(b[32:64])
+	return nil
+}
+
+// OSGenerateKey 外包服务器计算， 返回B1, B2, P
+// 其中，保存B1, B2, B1用于签名，B2用于解密加密密钥保护结构。
+// P发送给客户端。
+func (o *OSKeyGenerator) Step1(a1 *paillier.Cipher, a2 *paillier.Cipher, pk *paillier.PublicKey, rnd io.Reader) (*paillier.Cipher, *paillier.Cipher, *sm2.PublicKey, error) {
+	var d *big.Int
+	var err error
+	for {
+		d, err = rand.Int(rnd, sm2.OrderN())
+		if err != nil {
+			return nil, nil, nil, err
+		}
+		if d.Sign() > 0 {
+			break
+		}
+	}
+	di := new(big.Int).ModInverse(d, sm2.OrderN())
+	o.dc2 = d
+	o.dc2Inv = di
+
+	x, y := sm2.Curve256.ScalarBaseMult(di.Bytes())
+	b1 := new(paillier.Cipher).HomomorphicScalarMul(a1, d, pk)
+	b2 := new(paillier.Cipher).HomomorphicScalarMul(a2, di, pk)
+	return b1, b2, &sm2.PublicKey{Curve: sm2.Curve(), X: x, Y: y}, nil
+}
+
+func (o *OSKeyGenerator) Step2(R *sm2.PublicKey, S *sm2.PublicKey) (*sm2.PublicKey, *sm2.PublicKey, error) {
+	x1, y1 := sm2.Curve256.ScalarMult(R.X, R.Y, o.dc2Inv.Bytes())
+	x2, y2 := sm2.Curve256.ScalarMult(S.X, S.Y, o.dc2Inv.Bytes())
+	x, y := sm2.Curve256.Add(x2, y2, nGx, nGy)
+	return &sm2.PublicKey{Curve: sm2.Curve(), X: x1, Y: y1}, &sm2.PublicKey{Curve: sm2.Curve(), X: x, Y: y}, nil
+}