加解密

概述

如果对接者在接入前准备的第三方系统配置中，配置了AES+BASE64的加密策略，则需要对请求报文做加密，对返回结果做解密，本文给出加解密示例。
:::tip
目前加密策略仅对开票所有能力和收票的勾选接口起作用
:::

报文加密

加密前报文：

{
    "requestId": "1624601109096",
    "businessSystemCode": "BAIDU_TEST",
    "interfaceCode": "INVOICE.QUERY",
    "data": {
        "serialNo": "34234FPY123456refe4",
        "sellerTaxpayerId": "915003006188392540",
        "invoiceDateS": "2021-06-24 00:00:00",
        "invoiceDateE": "2021-06-26 00:00:00",
        "invoiceStatus": "",
        "invoiceType": "",
        "pageNo": 1,
        "pageSize": 50
    }
}

加密后报文：

{
    "requestId": "1624601109096",
    "businessSystemCode": "BAIDU_TEST",
    "interfaceCode": "INVOICE.QUERY",
    "data": "sdfsdf2332rfsdfSDF23RDS&@SDFSDFSDCX212423SDFSG4353454323423423DVDFDFG23RSDFSDCSDCV"
}

示例代码：

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.GCMParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.util.Base64;

public class AESUtil {
    private static final String KEY_ALGORITHM_AES = "AES";
    private static final String DEFAULT_CIPHER_ALGORITHM = "AES/GCM/NoPadding";
    private static final String CHARSET = "UTF-8";

    /**
     * 加密
     * @param content 原文
     * @param encryptPass AES加密KEY
     * @return
     */
    public static String aesEncrypt(String content, String encryptPass) {
        try {
            byte[] iv = new byte[12];
            SecureRandom secureRandom = new SecureRandom();
            secureRandom.nextBytes(iv);
            byte[] contentBytes = content.getBytes(CHARSET);
            Cipher cipher = Cipher.getInstance(DEFAULT_CIPHER_ALGORITHM);
            GCMParameterSpec params = new GCMParameterSpec(128, iv);
            cipher.init(Cipher.ENCRYPT_MODE, getSecretKey(encryptPass), params);
            byte[] encryptData = cipher.doFinal(contentBytes);
            assert encryptData.length == contentBytes.length + 16;
            byte[] message = new byte[12 + contentBytes.length + 16];
            System.arraycopy(iv, 0, message, 0, 12);
            System.arraycopy(encryptData, 0, message, 12, encryptData.length);
            return Base64.getEncoder().encodeToString(message);
        } catch (Exception e) {

        }
        return null;
    }

    /**
     * 解密
     * @param base64Content 密文
     * @param encryptPass AES加密KEY
     * @return
     */
    public static String aesDecrypt(String base64Content, String encryptPass) {
        try {
            byte[] content = Base64.getDecoder().decode(base64Content);
            if (content.length < 12 + 16) {
                throw new IllegalArgumentException();
            }
            GCMParameterSpec params = new GCMParameterSpec(128, content, 0, 12);
            Cipher cipher = Cipher.getInstance(DEFAULT_CIPHER_ALGORITHM);
            cipher.init(Cipher.DECRYPT_MODE, getSecretKey(encryptPass), params);
            byte[] decryptData = cipher.doFinal(content, 12, content.length - 12);
            return new String(decryptData, CHARSET);
        } catch (Exception e) {
        }
        return null;
    }

    /**
     * 秘钥
     * @return
     * @throws NoSuchAlgorithmException
     */
    private static SecretKeySpec getSecretKey(String encryptPass) throws NoSuchAlgorithmException {
        KeyGenerator kg = KeyGenerator.getInstance(KEY_ALGORITHM_AES);
        SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG");
        secureRandom.setSeed(encryptPass.getBytes());
        kg.init(128, secureRandom);
        SecretKey secretKey = kg.generateKey();
        return new SecretKeySpec(secretKey.getEncoded(), KEY_ALGORITHM_AES);
    }

    public static void main(String[] args) {
        String s = AESUtil.aesEncrypt("123456", "R5c58SI9toLpxBkv");
        System.out.println("加密密文：" + s);
        String p = AESUtil.aesDecrypt(s, "R5c58SI9toLpxBkv");
        System.out.println("解密：" + p);
    }
}

报文解密

对于业务接口data返回的数据，先进行base64解密，然后使用aesKey进行AES解密 （或直接调用示例代码里的AESUtil.aesDecrypt 方法）