Java中解密CryptoJS OpenSSL格式加密数据的教程

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.ParametersWithIV;
import org.bouncycastle.crypto.params.KeyParameter; // 用于获取派生出的密钥

public class CryptoJsAesDecryptor {

    public static String decryptCryptoJsOpenSslFormat(String encryptedBase64Token, String passwordStr) throws Exception {
        // 1. 提取盐值与密文
        byte[] saltCiphertext = Base64.getDecoder().decode(encryptedBase64Token);
        ByteBuffer byteBuffer = ByteBuffer.wrap(saltCiphertext);

        // 验证并跳过"Salted__"前缀
        byte[] prefix = new byte[8];
        byteBuffer.get(prefix);
        if (!new String(prefix, StandardCharsets.US_ASCII).equals("Salted__")) {
            throw new IllegalArgumentException("Invalid CryptoJs OpenSSL format: missing 'Salted__' prefix.");
        }

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

        // 提取实际密文
        byte[] ciphertext = new byte[byteBuffer.remaining()];
        byteBuffer.get(ciphertext);

        // 2. 密钥与IV派生 (使用BouncyCastle的OpenSSLPBEParametersGenerator)
        byte[] password = passwordStr.getBytes(StandardCharsets.UTF_8);
        OpenSSLPBEParametersGenerator pbeGenerator = new OpenSSLPBEParametersGenerator(new MD5Digest()); 
        pbeGenerator.init(password, salt);

        // 对于AES-256，密钥大小为256位，IV大小为128位
        // 注意：CryptoJS的keySize参数在字符串密码模式下，可能不直接代表最终密钥大小，
        // OpenSSL EVP_BytesToKey通常为AES派生256位密钥和128位IV。
        ParametersWithIV parameters = (ParametersWithIV) pbeGenerator.generateDerivedParameters(256, 128); 

        // 可选：获取派生出的密钥和IV，用于调试或进一步验证
        // byte[] derivedKey = ((KeyParameter)parameters.getParameters()).getKey();
        // byte[] derivedIV = parameters.getIV();

        // 3. 执行AES解密 (使用BouncyCastle)
        // 使用AES引擎，CBC模式，PKCS7填充
        PaddedBufferedBlockCipher cipher = new PaddedBufferedBlockCipher(new CBCBlockCipher(new AESEngine()));
        cipher.init(false, parameters); // false表示解密模式

        byte[] plaintext = new byte[cipher.getOutputSize(ciphertext.length)];
        int length = cipher.processBytes(ciphertext, 0, ciphertext.length, plaintext, 0);
        length += cipher.doFinal(plaintext, length);        

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

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

        try {
            String decryptedString = decryptCryptoJsOpenSslFormat(token, key);
            System.out.println("Decrypted Token: " + decryptedString); // 预期输出: {"name":"Burak","surName":"Bayraktaroglu"}
        } catch (Exception e) {
            System.err.println("Error during decryption: " + e.getMessage());
            e.printStackTrace();
        }
    }
}