init: v1.0.0

tpc/sm9/sm9m/sign.go

@@ -0,0 +1,80 @@
+package sm9m
+
+import (
+	"io"
+	"math/big"
+
+	"xdx.jelly/xgcl/gerrors"
+	"xdx.jelly/xgcl/sm/sm9"
+)
+
+// 签名流程
+// 1. 客户端生成随机数r, U = [r]*Kc, 发送m, U
+// 2. 服务端使用[ks]U作为完整用户私钥签名得到(h, S')
+// 3. 客户端计算S = [r^-1]S', 输出签名(h,S)
+
+type ClientSignContext struct {
+	r big.Int
+}
+
+type ClientSignParam struct {
+	p sm9.G1
+}
+
+// MarshalBinary implements the encoding.BinaryMarshaler interface
+func (cp *ClientSignParam) MarshalBinary() (data []byte, err error) {
+	return cp.p.Marshal(), nil
+}
+
+// UnmarshalBinary implements the encoding.BinaryUnmarshaler interface
+func (cp *ClientSignParam) UnmarshalBinary(data []byte) error {
+	_, err := cp.p.Unmarshal(data)
+	return err
+}
+
+// GenerateParam 客户端第一步
+func (c *ClientSignContext) GenerateParam(clientSignKey *SignKeyClient, rnd io.Reader) (*ClientSignParam, error) {
+	r, rInv, err := generatePairInt(rnd, sm9.N)
+	if err != nil {
+		return nil, err
+	}
+	clientParam := &ClientSignParam{}
+	clientParam.p.ScalarMult(&clientSignKey.p, rInv)
+
+	c.r.Set(r)
+	return clientParam, nil
+}
+
+// GenerateParam 客户端第二步
+func (c *ClientSignContext) GenerateSignature(param *ServerSignParam) (*sm9.Signature, error) {
+	param.sig.S.ScalarMult(&param.sig.S, &c.r)
+	return &param.sig, nil
+}
+
+type ServerSignParam struct {
+	sig sm9.Signature
+}
+
+// MarshalBinary implements the encoding.BinaryMarshaler interface
+func (sp *ServerSignParam) MarshalBinary() (data []byte, err error) {
+	return sp.sig.MarshalBinary()
+}
+
+// UnmarshalBinary implements the encoding.BinaryUnmarshaler interface
+func (sp *ServerSignParam) UnmarshalBinary(data []byte) error {
+	return sp.sig.UnmarshalBinary(data)
+}
+
+// ServerSign 服务端生成协同签名数据
+func ServerSign(hashed []byte, clientParam *ClientSignParam, serverSignKey *SignKeyServer, pubs *sm9.MastSignPublicKey, rnd io.Reader) (*ServerSignParam, error) {
+	ds := &sm9.UserSignKey{}
+	ds.G1.Set(&clientParam.p)
+	preSig, err := sm9.Sign(hashed, ds, pubs, rnd)
+	if err != nil {
+		return nil, gerrors.WithAnnotating(err, "ServerSign failed")
+	}
+	preSig.S.ScalarMult(&preSig.S, &serverSignKey.k)
+	param := &ServerSignParam{}
+	param.sig.Set(preSig)
+	return param, nil
+}