【新增】私有ca

backend/internal/private_ca/keygen.go

@@ -0,0 +1,40 @@
+package private_ca
+
+import (
+	"crypto/ecdsa"
+	"crypto/elliptic"
+	"crypto/rand"
+	"crypto/rsa"
+	"fmt"
+
+	gm "github.com/tjfoc/gmsm/sm2"
+)
+
+func generatePrivateKey(keyType KeyType, keyBits int) (interface{}, error) {
+	switch keyType {
+	case KeyRSA:
+		if keyBits == 0 {
+			keyBits = 2048
+		}
+		return rsa.GenerateKey(rand.Reader, keyBits)
+	case KeyECDSA:
+		var c elliptic.Curve
+		switch keyBits {
+		case 224:
+			c = elliptic.P224()
+		case 256:
+			c = elliptic.P256()
+		case 384:
+			c = elliptic.P384()
+		case 521:
+			c = elliptic.P521()
+		default:
+			c = elliptic.P384()
+		}
+		return ecdsa.GenerateKey(c, rand.Reader)
+	case KeySM2:
+		return gm.GenerateKey(rand.Reader)
+	default:
+		return nil, fmt.Errorf("unsupported key type: %s", keyType)
+	}
+}