HarmonyOS 的RSA解密问题？

import { buffer, util } from '@kit.ArkTS'; 
import { cryptoFramework } from '@kit.CryptoArchitectureKit'; 
/** 
 * 使用RSA非对称密钥（PKCS1模式）加密 
 * @param message 要加密的明文数据 
 * @returns 加密后的字符串，base64编码 
 */ 
export async function encryptRSA(message: string) { 
  // 服务器下发RSA公钥字符串（base64编码） 
  let pubKeyStr = "MIGfMA0GCSqGSIb3DQEBAQUAxxxxxxxxxxxxxCBiQKBgQDFQArxxxBXM4jHHuZGIb/kxxxxSjXkjqPLgrDmqBFxNyYxxxxO10nStQwdRkQkh5lZ5sqC1G/z6lyDPxxxx5GLZ2Tj4yinNjcMXmOwiHfyQAQo9LwdlyTedwRchg0fYexxxxxxxcWPowT1aA+GnQhYwNmaS/iKQsNxxxxQAB"; 
  // 初始化Base64工具实例 
  let base64Helper = new util.Base64Helper(); 
  // 公钥转换为Uint8Array，然后包装为DataBlob类型 
  let pubKeyBlob: cryptoFramework.DataBlob = { data: base64Helper.decodeSync(pubKeyStr) }; 
  // 创建RSA key生成器 
  let rsaGenerator = cryptoFramework.createAsyKeyGenerator('RSA1024'); 
  // 将公钥包装数据pubKeyBlob转换成密钥对类型KeyPair 
  let keyPair = await rsaGenerator.convertKey(pubKeyBlob, null); 
  // 创建 Cipher对象 
  let cipher = cryptoFramework.createCipher('RSA1024|PKCS1'); 
  // 初始化加密模式，指定密钥keyPair.pubKey 
  await cipher.init(cryptoFramework.CryptoMode.ENCRYPT_MODE, keyPair.pubKey, null); 
  // 包装要加密的明文 
  let plainTextBlob: cryptoFramework.DataBlob = { data: new Uint8Array(buffer.from(message, 'utf-8').buffer) }; 
  // 传入明文，获取加密后的数据 
  let encryptBlob = await cipher.doFinal(plainTextBlob); 
  // 返回加密后的字符串 
  return base64Helper.encodeToStringSync(encryptBlob.data); 
}