diff --git a/license/crypto.go b/license/crypto.go
index aa31ada..9dcdda2 100644
--- a/license/crypto.go
+++ b/license/crypto.go
@@ -1,47 +1,60 @@
 package license
 
 import (
-	"crypto"
 	"crypto/ecdsa"
 	"crypto/elliptic"
 	"crypto/rand"
-	"crypto/rsa"
 	"crypto/sha256"
-	"crypto/x509"
+	"encoding/asn1"
 	"encoding/base64"
-	"encoding/pem"
+	"math/big"
 )
 
-var (
-	privateKey *ecdsa.PrivateKey
-)
+var privateKey *ecdsa.PrivateKey
 
 func init() {
-	privateKey, _ = ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
+	var err error
+	privateKey, err = ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
+	if err != nil {
+		panic(err)
+	}
 }
 
-func SignPayload(payload []byte) (string, error) {
-	hash := sha256.Sum256(payload)
+// ecdsaSignature 是 ASN.1 编码中使用的结构体
+type ecdsaSignature struct {
+	R, S *big.Int
+}
+
+func SignPayload(message []byte) (string, error) {
+	hash := sha256.Sum256(message)
 	r, s, err := ecdsa.Sign(rand.Reader, privateKey, hash[:])
 	if err != nil {
 		return "", err
 	}
 
-	sig := append(r.Bytes(), s.Bytes()...)
+	sig, err := asn1.Marshal(ecdsaSignature{r, s})
+	if err != nil {
+		return "", err
+	}
 	return base64.StdEncoding.EncodeToString(sig), nil
 }
 
-func VerifySignature(pub *rsa.PublicKey, message []byte, signatureBase64 string) bool {
-	signature, err := base64.StdEncoding.DecodeString(signatureBase64)
+func VerifySignature(pub *ecdsa.PublicKey, message []byte, signatureBase64 string) bool {
+	sigBytes, err := base64.StdEncoding.DecodeString(signatureBase64)
 	if err != nil {
 		return false
 	}
-	hashed := sha256.Sum256(message)
-	err = rsa.VerifyPKCS1v15(pub, crypto.SHA256, hashed[:], signature)
-	return err == nil
+
+	var sig ecdsaSignature
+	_, err = asn1.Unmarshal(sigBytes, &sig)
+	if err != nil {
+		return false
+	}
+
+	hash := sha256.Sum256(message)
+	return ecdsa.Verify(pub, hash[:], sig.R, sig.S)
 }
 
-func ExportPublicKeyPEM() string {
-	pubKeyBytes, _ := x509.MarshalPKIXPublicKey(&privateKey.PublicKey)
-	return string(pem.EncodeToMemory(&pem.Block{Type: "PUBLIC KEY", Bytes: pubKeyBytes}))
+func GetPublicKey() *ecdsa.PublicKey {
+	return &privateKey.PublicKey
 }
diff --git a/license/service.go b/license/service.go
index f1003ae..2c4eef2 100644
--- a/license/service.go
+++ b/license/service.go
@@ -13,15 +13,25 @@ func GenerateLicenseHandler(db storage.Database) fiber.Handler {
 	return func(c *fiber.Ctx) error {
 		var req LicenseRequest
 		if err := c.BodyParser(&req); err != nil {
-			return fiber.ErrBadRequest
+			return fiber.NewError(fiber.StatusBadRequest, "Invalid request body")
 		}
 
-		payloadBytes, _ := json.Marshal(req)
-		payloadB64 := base64.StdEncoding.EncodeToString(payloadBytes)
-		signature, _ := SignPayload(payloadBytes)
+		if req.MachineID == "" || req.Expiry == "" {
+			return fiber.NewError(fiber.StatusBadRequest, "Missing required fields")
+		}
+
+		payloadBytes, err := json.Marshal(req)
+		if err != nil {
+			return fiber.NewError(fiber.StatusInternalServerError, "Failed to encode payload")
+		}
+
+		signature, err := SignPayload(payloadBytes)
+		if err != nil {
+			return fiber.NewError(fiber.StatusInternalServerError, "Signing failed")
+		}
 
 		licenseFile := LicenseFile{
-			Payload:   payloadB64,
+			Payload:   base64.StdEncoding.EncodeToString(payloadBytes),
 			Signature: signature,
 		}
 
@@ -33,25 +43,40 @@ func ActivateLicenseHandler(db storage.Database) fiber.Handler {
 	return func(c *fiber.Ctx) error {
 		var lf LicenseFile
 		if err := c.BodyParser(&lf); err != nil {
-			return fiber.ErrBadRequest
+			return fiber.NewError(fiber.StatusBadRequest, "Invalid license format")
+		}
+
+		payloadBytes, err := base64.StdEncoding.DecodeString(lf.Payload)
+		if err != nil {
+			return fiber.NewError(fiber.StatusBadRequest, "Invalid base64 payload")
+		}
+
+		if !VerifySignature(GetPublicKey(), payloadBytes, lf.Signature) {
+			return fiber.NewError(fiber.StatusUnauthorized, "Invalid license signature")
 		}
 
-		payloadBytes, _ := base64.StdEncoding.DecodeString(lf.Payload)
 		var req LicenseRequest
-		json.Unmarshal(payloadBytes, &req)
+		if err := json.Unmarshal(payloadBytes, &req); err != nil {
+			return fiber.NewError(fiber.StatusBadRequest, "Malformed payload")
+		}
+
+		if req.MachineID == "" {
+			return fiber.NewError(fiber.StatusBadRequest, "Missing machine ID")
+		}
 
 		if db.HasActivated(req.MachineID) {
-			return fiber.NewError(403, "This machine is already activated.")
+			return fiber.NewError(fiber.StatusForbidden, "This machine is already activated")
 		}
 
-		if !VerifySignature(&privateKey.PublicKey, payloadBytes, lf.Signature) {
-			return fiber.NewError(401, "Invalid license signature")
+		expiry, err := time.Parse("2006-01-02", req.Expiry)
+		if err != nil || time.Now().After(expiry) {
+			return fiber.NewError(fiber.StatusForbidden, "License is invalid or expired")
 		}
 
-		licenseText := lf.Payload + "." + lf.Signature
-		db.SaveActivation(req.MachineID, licenseText)
+		// 绑定激活记录
+		db.SaveActivation(req.MachineID, lf.Payload+"."+lf.Signature)
 
-		return c.SendString("License activated successfully.")
+		return c.JSON(fiber.Map{"status": "success", "message": "License activated successfully"})
 	}
 }
 
@@ -59,33 +84,33 @@ func ValidateLicenseHandler(db storage.Database) fiber.Handler {
 	return func(c *fiber.Ctx) error {
 		var lf LicenseFile
 		if err := c.BodyParser(&lf); err != nil {
-			return fiber.ErrBadRequest
+			return fiber.NewError(fiber.StatusBadRequest, "Invalid license format")
 		}
 
 		payloadBytes, err := base64.StdEncoding.DecodeString(lf.Payload)
 		if err != nil {
-			return fiber.NewError(fiber.StatusBadRequest, "Invalid payload encoding")
+			return fiber.NewError(fiber.StatusBadRequest, "Invalid base64 payload")
 		}
 
-		// 先验证签名是否真的是对 payloadBytes 签的
-		if !VerifySignature(&privateKey.PublicKey, payloadBytes, lf.Signature) {
+		if !VerifySignature(GetPublicKey(), payloadBytes, lf.Signature) {
 			return fiber.NewError(fiber.StatusUnauthorized, "Invalid license signature")
 		}
 
-		// 验证通过后再解析 payload 内容
 		var req LicenseRequest
 		if err := json.Unmarshal(payloadBytes, &req); err != nil {
 			return fiber.NewError(fiber.StatusBadRequest, "Malformed payload")
 		}
 
 		expiry, err := time.Parse("2006-01-02", req.Expiry)
-		if err != nil {
-			return fiber.NewError(fiber.StatusBadRequest, "Invalid expiry date")
-		}
-		if time.Now().After(expiry) {
+		if err != nil || time.Now().After(expiry) {
 			return fiber.NewError(fiber.StatusForbidden, "License expired")
 		}
 
-		return c.JSON(fiber.Map{"valid": true, "features": req.Features})
+		return c.JSON(fiber.Map{
+			"valid":    true,
+			"features": req.Features,
+			"machine":  req.MachineID,
+			"expiry":   req.Expiry,
+		})
 	}
 }