java使用AES-256-ECB（PKCS7Padding）解密——微信支付退款通知接口指定解密方式

本文轉載自查看原文 2019-12-06 10:42 981 加密解密/ java加密解密

1.場景

　　在做微信支付退款通知接口時，微信對通知的內容做了加密，並且指定用 AES256 解密，官方指定的解密方式如下：

2.導包

<!-- https://mvnrepository.com/artifact/org.bouncycastle/bcprov-jdk15on -->
        <dependency>
            <groupId>org.bouncycastle</groupId>
            <artifactId>bcprov-jdk15on</artifactId>
            <version>1.60</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.jasypt/jasypt -->
        <dependency>
            <groupId>org.jasypt</groupId>
            <artifactId>jasypt</artifactId>
            <version>1.9.3</version>
        </dependency>

3.解密

　　說明：方法中參數 reqInfo 就是退款結果通知接口中的 req_info 字段值

private String descrypt(String reqInfo) throws NoSuchPaddingException, NoSuchAlgorithmException, NoSuchProviderException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException {
        byte[] reqInfoB = Base64.decodeBase64(reqInfo);
        String key_ = DigestUtils.md5Hex(WXPayConfig.getInstance().getKey()).toLowerCase();

        if (Security.getProvider("BC") == null){
            Security.addProvider(new BouncyCastleProvider());
        }
        Cipher cipher = Cipher.getInstance("AES/ECB/PKCS7Padding", "BC");
        SecretKeySpec secretKeySpec = new SecretKeySpec(key_.getBytes(), "AES");
        cipher.init(Cipher.DECRYPT_MODE, secretKeySpec);
        return new String(cipher.doFinal(reqInfoB));
    }