update go-api

GetDigestNames() and GetCipherNames get supported algorithms with
callbacks.

go/gmssltest/gmssltest.go

@@ -28,13 +28,7 @@ func main() {
 	}
 	fmt.Println("");
 
-	fmt.Println("Supported Message Authentication Codes:")
-	macs := gmssl.GetMacNames()
-	for _, mac := range macs {
-		fmt.Println("    " + mac)
-	}
-	fmt.Println("");
-
+	/* sm3 digest */
 	sm3, err := gmssl.NewDigestContext("SM3", nil)
 	if err != nil {
 		fmt.Println(err)
@@ -55,45 +49,92 @@ func main() {
 	}
 	fmt.Printf("sm3(\"abc\") = %x\n", sm3digest)
 
+	/* hmac-sm3 */
 	hmac_sm3, err := gmssl.NewHMACContext("SM3", nil, []byte("this is the key"))
 	if err != nil {
-		fmt.Println("shit1")
+		fmt.Println(err)
 		return
 	}
 	if err := hmac_sm3.Update([]byte("hello")); err != nil {
-		fmt.Println("shit2")
+		fmt.Println(err)
 		return
 	}
 	if err := hmac_sm3.Update([]byte("world")); err != nil {
-		fmt.Println("shit3")
+		fmt.Println(err)
 		return
 	}
 	mactag, err := hmac_sm3.Final()
 	if err != nil {
-		fmt.Println("shit4")
+		fmt.Println(err)
 		return
 	}
 	fmt.Printf("hmac-sm3() = %x\n", mactag)
 
-	/*
-	key := []byte("key")
-	iv := []byte("iv")
-	sms4, err := gmssl.NewCipherContext("SMS4", nil, key, iv, true)
+	/* generate random key */
+	keylen, err := gmssl.GetCipherKeyLength("SMS4")
 	if err != nil {
+		fmt.Println(err)
+		return
+	}
+	key, err := gmssl.GenerateRandom(keylen)
+	if err != nil {
+		fmt.Println(err)
+		return
 	}
 
-	ciphertext1, err := sms4.Update([]byte("hello"))
+	/* generate random iv */
+	ivlen, err := gmssl.GetCipherIVLength("SMS4")
 	if err != nil {
+		fmt.Println(err)
+		return
+	}
+	iv, err := gmssl.GenerateRandom(ivlen)
+	if err != nil {
+		fmt.Println(err)
+		return
 	}
 
-	ciphertext2, err := sms4.Final()
+	/* encrypt */
+	encryptor, err := gmssl.NewCipherContext("SMS4", nil, key, iv, true)
 	if err != nil {
+		fmt.Println(err)
+		return
+	}
+	ciphertext1, err := encryptor.Update([]byte("hello"))
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+	ciphertext2, err := encryptor.Final()
+	if err != nil {
+		fmt.Println(err)
+		return
 	}
-
 	ciphertext := make([]byte, 0, len(ciphertext1) + len(ciphertext2))
 	ciphertext = append(ciphertext, ciphertext1...)
 	ciphertext = append(ciphertext, ciphertext2...)
-	fmt.Printf("%x", ciphertext)
-	*/
+	fmt.Printf("sms4(\"hello\") = %x\n", ciphertext)
+
+	/* decrypt */
+	decryptor, err := gmssl.NewCipherContext("SMS4", nil, key, iv, false)
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+	plaintext1, err := decryptor.Update(ciphertext)
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+	plaintext2, err := decryptor.Final()
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+	plaintext := make([]byte, 0, len(plaintext1) + len(plaintext2))
+	plaintext = append(plaintext, plaintext1...)
+	plaintext = append(plaintext, plaintext2...)
+	fmt.Println(string(plaintext))
+
 }