从Node.js到Java：实现AES-256-CBC加解密

        let encKey = "0Z8ZUcy1Qh8lnt199MTwTPEe2g1E2tE3";
        encKey = crypto.createHash('sha256').update(encKey).digest('bin').slice(0, 32);
        let char = String.fromCharCode(0x0);
        let iv = char + char + char + char + char + char + char + char + char + char + char + char + char + char + char + char;
        let decryptor = crypto.createDecipheriv("aes-256-cbc", encKey, iv);
        let dec = decryptor.update(someAuthString, 'base64', 'utf8') + decryptor.final('utf8');
        dec = removePKCS5Padding(dec); // 自定义移除填充函数

// removePKCS5Padding 函数
function removePKCS5Padding(text) {
    let pad = ord(text[text.length - 1]);
    pad = text.substr(0, -1 * pad)
    if (_.isEmpty(pad)) {
        return text;
    } else {
        return pad;
    }
}

import java.security.MessageDigest;
import java.nio.charset.StandardCharsets;

// 原始密钥字符串
String originalKey = "0Z8ZUcy1Qh8lnt199MTwTPEe2g1E2tE3";
// 将字符串转换为字节数组，注意编码一致性
byte[] keyBytes = originalKey.getBytes(StandardCharsets.US_ASCII); // 或 StandardCharsets.UTF_8，取决于Node.js实际使用的编码
// 获取SHA-256实例并计算哈希
MessageDigest sha256 = MessageDigest.getInstance("SHA-256");
byte[] derivedKey = sha256.doFinal(keyBytes);
// derivedKey 现在就是32字节的AES密钥

byte[] ivBytes = new byte[16]; // Java会自动将byte数组元素初始化为0
// 或者明确填充零：
// Arrays.fill(ivBytes, (byte) 0);

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

// 创建SecretKeySpec对象，用于AES密钥
SecretKeySpec secretKeySpec = new SecretKeySpec(derivedKey, "AES");
// 创建IvParameterSpec对象，用于IV
IvParameterSpec ivParameterSpec = new IvParameterSpec(ivBytes);

// 获取Cipher实例，指定"算法/模式/填充"
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
// 初始化Cipher为解密模式
cipher.init(Cipher.DECRYPT_MODE, secretKeySpec, ivParameterSpec);

import java.util.Base64;

// 假设 someAuthString 是Base64编码的密文字符串
String someAuthString = "your_base64_encoded_ciphertext_here";

// 将Base64编码的密文解码为字节数组
byte[] encryptedBytes = Base64.getDecoder().decode(someAuthString);

// 执行解密操作
byte[] decryptedBytes = cipher.doFinal(encryptedBytes);

// 将解密后的字节数组转换为字符串，注意编码一致性
String clearText = new String(decryptedBytes, StandardCharsets.UTF_8);

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
import javax.crypto.spec.IvParameterSpec;
import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.util.Base64;
import java.util.Arrays; // For explicit IV fill, though not strictly necessary

public class AesDecryptionService {

    public static String decrypt(String originalKeyString, String base64Ciphertext) throws Exception {
        // 1. 密钥派生：SHA-256哈希
        byte[] keyBytes = originalKeyString.getBytes(StandardCharsets.US_ASCII); // 根据Node.js实际编码调整
        MessageDigest sha256 = MessageDigest.getInstance("SHA-256");
        byte[] derivedKey = sha256.doFinal(keyBytes);

        // 2. 初始化向量（IV）的构建 (16字节全零IV)
        byte[] ivBytes = new byte[16];
        // Java会自动初始化为零，如果需要明确，可以使用Arrays.fill
        // Arrays.fill(ivBytes, (byte) 0); 

        // 3. Cipher对象的初始化
        SecretKeySpec secretKeySpec = new SecretKeySpec(derivedKey, "AES");
        IvParameterSpec ivParameterSpec = new IvParameterSpec(ivBytes);

        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        cipher.init(Cipher.DECRYPT_MODE, secretKeySpec, ivParameterSpec);

        // 4. 解密操作的执行
        byte[] encryptedBytes = Base64.getDecoder().decode(base64Ciphertext);
        byte[] decryptedBytes = cipher.doFinal(encryptedBytes);

        // 将解密后的字节数组转换为字符串
        return new String(decryptedBytes, StandardCharsets.UTF_8);
    }

    public static void main(String[] args) {
        String nodeJsEncKey = "0Z8ZUcy1Qh8lnt199MTwTPEe2g1E2tE3";
        // 假设这是Node.js加密后输出的Base64编码密文
        String someAuthString = "YOUR_BASE64_ENCODED_CIPHERTEXT_HERE"; 
        // 替换为实际的密文，例如：
        // String someAuthString = "f+z+v... (实际的Base64密文)"; 

        try {
            String decryptedText = decrypt(nodeJsEncKey, someAuthString);
            System.out.println("Decrypted Text: " + decryptedText);
        } catch (Exception e) {
            System.err.println("Decryption failed: " + e.getMessage());
            e.printStackTrace();
        }
    }
}