diff --git a/sm3/sm3.go b/sm3/sm3.go
index 094cfb2..e221784 100644
--- a/sm3/sm3.go
+++ b/sm3/sm3.go
@@ -50,17 +50,17 @@ func (d *digest) MarshalBinary() ([]byte, error) {
 
 func (d *digest) AppendBinary(b []byte) ([]byte, error) {
 	b = append(b, magic...)
-	b = appendUint32(b, d.h[0])
-	b = appendUint32(b, d.h[1])
-	b = appendUint32(b, d.h[2])
-	b = appendUint32(b, d.h[3])
-	b = appendUint32(b, d.h[4])
-	b = appendUint32(b, d.h[5])
-	b = appendUint32(b, d.h[6])
-	b = appendUint32(b, d.h[7])
+	b = byteorder.BEAppendUint32(b, d.h[0])
+	b = byteorder.BEAppendUint32(b, d.h[1])
+	b = byteorder.BEAppendUint32(b, d.h[2])
+	b = byteorder.BEAppendUint32(b, d.h[3])
+	b = byteorder.BEAppendUint32(b, d.h[4])
+	b = byteorder.BEAppendUint32(b, d.h[5])
+	b = byteorder.BEAppendUint32(b, d.h[6])
+	b = byteorder.BEAppendUint32(b, d.h[7])
 	b = append(b, d.x[:d.nx]...)
 	b = append(b, make([]byte, len(d.x)-d.nx)...)
-	b = appendUint64(b, d.len)
+	b = byteorder.BEAppendUint64(b, d.len)
 	return b, nil
 }
 
@@ -86,29 +86,12 @@ func (d *digest) UnmarshalBinary(b []byte) error {
 	return nil
 }
 
-func appendUint64(b []byte, x uint64) []byte {
-	var a [8]byte
-	byteorder.BEPutUint64(a[:], x)
-	return append(b, a[:]...)
-}
-
-func appendUint32(b []byte, x uint32) []byte {
-	var a [4]byte
-	byteorder.BEPutUint32(a[:], x)
-	return append(b, a[:]...)
-}
-
 func consumeUint64(b []byte) ([]byte, uint64) {
-	_ = b[7]
-	x := uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
-		uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
-	return b[8:], x
+	return b[8:], byteorder.BEUint64(b)
 }
 
 func consumeUint32(b []byte) ([]byte, uint32) {
-	_ = b[3]
-	x := uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24
-	return b[4:], x
+	return b[4:], byteorder.BEUint32(b)
 }
 
 // New returns a new hash.Hash computing the SM3 checksum. The Hash