szwlServer/src/main/java/com/szwl/util/HuifuUtils.java

package com.szwl.util;

import cn.hutool.core.util.RandomUtil;
import com.huifu.bspay.sdk.opps.core.utils.DateTools;
import lombok.extern.slf4j.Slf4j;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.security.KeyFactory;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.Signature;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.Base64;

@Slf4j
public class HuifuUtils {

    /**
     * RSA私钥签名：签名方式SHA256WithRSA
     * @param data 待签名字符串
     * @param privateKeyBase64 私钥（Base64编码）
     * @return 签名byte[]
     * @throws Exception
     */
    public static String sign(String data, String privateKeyBase64) {
        // Base64 --> Key
        try {
            byte[] bytes = Base64.getDecoder().decode(privateKeyBase64);
            PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(bytes);
            KeyFactory keyFactory;
            keyFactory = KeyFactory.getInstance("RSA");
            PrivateKey privateKey = keyFactory.generatePrivate(keySpec);
            // Sign
            Signature signature = Signature.getInstance("SHA256WithRSA");
            signature.initSign(privateKey);
            signature.update(data.getBytes("UTF-8"));
            return Base64.getEncoder().encodeToString(signature.sign());
        } catch (Exception e) {
            return null;
        }
    }

    /**
     * 使用汇付RSA公钥验签
     * @param data 待签名字符串
     * @param publicKeyBase64 公钥（Base64编码）
     * @return 验签结果
     * @throws Exception
     */
    public static boolean verify(String data, String publicKeyBase64, String sign) {
        // Base64 --> Key
        try {
            byte[] bytes = Base64.getDecoder().decode(publicKeyBase64);
            X509EncodedKeySpec keySpec = new X509EncodedKeySpec(bytes);
            KeyFactory keyFactory;
            keyFactory = KeyFactory.getInstance("RSA");
            PublicKey publicKey = keyFactory.generatePublic(keySpec);
            // verify
            Signature signature = Signature.getInstance("SHA256WithRSA");
            signature.initVerify(publicKey);
            signature.update(data.getBytes("UTF-8"));
            return signature.verify(Base64.getDecoder().decode(sign));
        } catch (Exception e) {
            log.error("Exception", e);
            return false;
        }

    }

    /**
     * 生成随机流水号
     * @return
     */
    public static String initReqSeqId() {
        String numbers = RandomUtil.randomNumbers(10);
        return new StringBuilder(DateTools.getCurrentDateTimeYYYYMMDDHHMMSSSSS()).append(numbers).toString();
    }

    /**
     * 转base64为图片
     * @param base64Str
     * @return
     * @throws IOException
     */
    public static File base64ToTempImage(String base64Str) throws IOException {
        // 解码base64字符串
        byte[] imageBytes = Base64.getDecoder().decode(base64Str.split(",")[1]);

        // 创建一个临时文件
        File tempFile = File.createTempFile("temp_image", ".jpg");

        // 将解码后的数据写入临时文件
        try (FileOutputStream fos = new FileOutputStream(tempFile)) {
            fos.write(imageBytes);
        }

        // 返回临时文件
        return tempFile;
    }
}