diff --git a/include/openssl/sm2_standard_exch.h b/include/openssl/sm2_standard_exch.h
index b6a6d217..aad10a2d 100644
--- a/include/openssl/sm2_standard_exch.h
+++ b/include/openssl/sm2_standard_exch.h
@@ -1,9 +1,7 @@
 #include "miracl.h"
 #include "mirdef.h"
+#include "kdf_standard_exch.h"
 
-#define SM2_WORDSIZE 8
-#define SM2_NUMBITS 256
-#define SM2_NUMWORD (SM2_NUMBITS / SM2_WORDSIZE)	//32
 #define ERR_INFINITY_POINT 0x00000001
 #define ERR_NOT_VALID_ELEMENT 0x00000002
 #define ERR_NOT_VALID_POINT 0x00000003