Java中实现CryptoJS AES解密的等效方法

<dependency>
    <groupId>org.bouncycastle</groupId>
    <artifactId>bcprov-jdk15on</artifactId>
    <version>1.70</version> <!-- 或更高版本 -->
</dependency>

import java.nio.ByteBuffer;
import java.nio.charset.StandardCharsets;
import java.util.Base64;

import org.bouncycastle.crypto.digests.MD5Digest;
import org.bouncycastle.crypto.engines.AESEngine;
import org.bouncycastle.crypto.generators.OpenSSLPBEParametersGenerator;
import org.bouncycastle.crypto.modes.CBCBlockCipher;
import org.bouncycastle.crypto.paddings.PaddedBufferedBlockCipher;
import org.bouncycastle.crypto.params.KeyParameter;
import org.bouncycastle.crypto.params.ParametersWithIV;

public class CryptoJsAesDecryptor {

    public static String decryptCryptoJsAes(String encryptedBase64Token, String passwordStr) throws Exception {

        // 1. 从Base64编码的密文中提取盐值和实际密文
        // CryptoJS生成的密文格式为：Base64(Salted__ + salt + ciphertext)
        byte[] saltCiphertext = Base64.getDecoder().decode(encryptedBase64Token);
        ByteBuffer byteBuffer = ByteBuffer.wrap(saltCiphertext);

        // 验证前缀是否为 "Salted__"
        byte[] prefix = new byte[8];
        byteBuffer.get(prefix);
        String prefixStr = new String(prefix, StandardCharsets.US_ASCII);
        if (!"Salted__".equals(prefixStr)) {
            throw new IllegalArgumentException("Invalid CryptoJs encrypted token format: missing 'Salted__' prefix.");
        }

        // 提取8字节的盐值
        byte[] salt = new byte[8];
        byteBuffer.get(salt);

        // 提取剩余的实际密文
        byte[] ciphertext = new byte[byteBuffer.remaining()];
        byteBuffer.get(ciphertext);

        // 2. 使用OpenSSL EVP_BytesToKey() 算法派生密钥和IV (通过BouncyCastle实现)
        byte[] password = passwordStr.getBytes(StandardCharsets.UTF_8);

        // OpenSSLPBEParametersGenerator 实现了 EVP_BytesToKey 算法
        // CryptoJs默认使用MD5作为哈希函数
        OpenSSLPBEParametersGenerator pbeGenerator = new OpenSSLPBEParametersGenerator(new MD5Digest()); 
        // 初始化生成器，传入密码和盐值
        pbeGenerator.init(password, salt);

        // 生成派生参数：256位密钥 (32字节), 128位IV (16字节)
        // 注意：AES-256需要256位密钥，CBC模式需要128位IV
        ParametersWithIV parameters = (ParametersWithIV) pbeGenerator.generateDerivedParameters(256, 128); 

        // 可以通过以下方式获取派生出的密钥和IV，但通常直接传递parameters对象给cipher即可
        // byte[] derivedKey = ((KeyParameter)parameters.getParameters()).getKey();
        // byte[] derivedIV = parameters.getIV();

        // 3. 使用派生出的密钥和IV进行AES解密 (通过BouncyCastle实现)
        // 创建一个带有填充的块密码，使用CBC模式和AES引擎
        PaddedBufferedBlockCipher cipher = new PaddedBufferedBlockCipher(new CBCBlockCipher(new AESEngine()));

        // 初始化解密器：false表示解密模式，parameters包含密钥和IV
        cipher.init(false, parameters); // false for decrypt mode

        // 创建一个足够大的缓冲区来存储解密后的明文
        byte[] plaintext = new byte[cipher.getOutputSize(ciphertext.length)];

        // 处理密文数据
        int length = cipher.processBytes(ciphertext, 0, ciphertext.length, plaintext, 0);
        // 完成解密过程，处理任何剩余的字节并移除填充
        length += cipher.doFinal(plaintext, length);        

        // 将解密后的字节数组转换为UTF-8字符串
        String plaintextStr = new String(plaintext, 0, length, StandardCharsets.UTF_8);
        return plaintextStr;
    }

    public static void main(String[] args) {
        String token = "U2FsdGVkX1+6YueVRKp6h0dZfk/a8AC9vyFfAjxD4nb7mXsKrM7rI7xZ0OgrF1sShHYNLMJglz4+67n/I7P+fg==";
        String key = "p80a0811-47db-2c39-bcdd-4t3g5h2d5d1a";

        try {
            String decryptedData = decryptCryptoJsAes(token, key);
            System.out.println("Decrypted Data: " + decryptedData); // 预期输出: {"name":"Burak","surName":"Bayraktaroglu"}
            // 如果解密结果是JSON字符串，可以进一步解析
            // JSONObject jsonObject = new JSONObject(decryptedData); // 假设使用org.json库
            // System.out.println("Name: " + jsonObject.getString("name"));
        } catch (Exception e) {
            System.err.println("Decryption failed: " + e.getMessage());
            e.printStackTrace();
        }
    }
}