golang 生成rsa秘鑰對

需求：golang生成秘鑰對，秘鑰有密碼

package main

import (
	"crypto/rand"
	"crypto/rsa"
	"crypto/x509"
	"encoding/pem"
	"fmt"
	"os"
)

func generateRSAKey(pripath, pubpath, passwd string) error {
	privateKey, err := rsa.GenerateKey(rand.Reader, 2048)
	if err != nil {
		return err
	}

	//通過x509標准將得到的ras私鑰序列化為ASN.1 的 DER編碼字符串
	x509PrivateKey := x509.MarshalPKCS1PrivateKey(privateKey)

	//使用pem格式對x509輸出的內容進行編碼
	privateFile, err := os.Create(pripath)
	if err != nil {
		return err
	}
	defer privateFile.Close()

	//構建一個pem.Block結構體對象
	//privateBlock := pem.Block{Type: "RSA Private Key", Bytes: X509PrivateKey}
	privateBlock, err := x509.EncryptPEMBlock(rand.Reader, "RSA Private Key", x509PrivateKey, []byte(passwd), x509.PEMCipherAES256)
	if err != nil {
		return err
	}

	//將數據保存到文件
	err = pem.Encode(privateFile, privateBlock)
	if err != nil {
		return err
	}

	//X509對公鑰編碼
	X509PublicKey, err := x509.MarshalPKIXPublicKey(&privateKey.PublicKey)
	if err != nil {
		return err
	}

	//pem格式編碼
	publicFile, err := os.Create(pubpath)
	if err != nil {
		return err
	}
	defer publicFile.Close()

	//創建一個pem.Block結構體對象
	publicBlock := pem.Block{Type: "RSA Public Key", Bytes: X509PublicKey}
	//將數據保存到文件
	err = pem.Encode(publicFile, &publicBlock)
	if err != nil {
		return err
	}

	return nil
}

func genkey(name, passwd string) error {
	err := generateRSAKey(name+".pri", name+".pub", passwd)
	if err != nil {
		fmt.Println("Rsa key gen failed", err)
		return err
	}

	fmt.Printf("Gen privatekey: %s, publickey: %s\n", name+".pri", name+".pub")
	return nil
}

func main() {
	genkey("rsa", "password")
}