记微信支付的一个大坑

sql

Posted by TGich on December 5, 2017

微信退款结果通知报文AES解密

最近做微信支付涉及到退款,查看官方文档,发现通知报文是加密的,解密方式如下: (1)对加密串A做base64解码,得到加密串B (2)对商户key做md5,得到32位小写key* ( key设置路径:微信商户平台(pay.weixin.qq.com)–>账户设置–>API安全–>密钥设置 ) (3)用key*对加密串B做AES解密 这里分别涉及到了BASE64,MD5,AES三种技术,前两点很好理解,第三点说的太简单了,并没有指出算法的工作模式和填充方式。百度之后发现了一篇文章中提到了是使用了AES/ECB/PKCS5Padding,那就OK了,参考代码:

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;

public class AESUtil {

	/**
	 * 密钥算法
	 */
	private static final String ALGORITHM = "AES";
	/**
	 * 加解密算法/工作模式/填充方式
	 */
	private static final String ALGORITHM_MODE_PADDING = "AES/ECB/PKCS5Padding";
	/**
	 * 生成key
	 */
	private static SecretKeySpec key = new SecretKeySpec(MD5Util.MD5Encode("your password", "UTF-8").toLowerCase().getBytes(), ALGORITHM);

	/**
	 * AES加密
	 *
	 * @param data
	 * @return
	 * @throws Exception
	 */
	public static String encryptData(String data) throws Exception {
		// 创建密码器
		Cipher cipher = Cipher.getInstance(ALGORITHM_MODE_PADDING);
		// 初始化
		cipher.init(Cipher.ENCRYPT_MODE, key);
		return Base64Util.encode(cipher.doFinal(data.getBytes()));
	}

	/**
	 * AES解密
	 *
	 * @param base64Data
	 * @return
	 * @throws Exception
	 */
	public static String decryptData(String base64Data) throws Exception {
		Cipher cipher = Cipher.getInstance(ALGORITHM_MODE_PADDING);
		cipher.init(Cipher.DECRYPT_MODE, key);
		return new String(cipher.doFinal(Base64Util.decode(base64Data)));
	}

	public static void main(String[] args) throws Exception {
		String A = "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";
		String B = AESUtil.decryptData(A);
		System.out.println(B);
	}

}