无法用Java解密AES-256 GCM

Question

节点模块：

var crypto = require('crypto');

var encrypt = function(masterkey, plainText) {
    // random initialization vector
    var iv = crypto.randomBytes(12);

    // random salt
    var salt = crypto.randomBytes(64);

    var key = masterkey;

    // AES 256 GCM Mode
    var cipher = crypto.createCipheriv('aes-256-gcm', key, iv);

    // encrypt the given text
    var encrypted = Buffer.concat([cipher.update(plainText, 'utf8'), cipher.final()]);

    // extract the auth tag
    var tag = cipher.getAuthTag();

    return Buffer.concat([salt, iv, encrypted, tag]).toString('base64');
};

var decrypt = function(masterkey, encryptedText) {
    // base64 decoding
    var bData = new Buffer(encryptedText, 'base64');

    // convert data to buffers
    var salt = bData.slice(0, 64);
    var iv = bData.slice(64, 76);
    var tag = bData.slice(bData.length - 16, bData.length);
    var text = bData.slice(76, bData.length - 16);

    var key = masterkey;

    // AES 256 GCM Mode
    var decipher = crypto.createDecipheriv('aes-256-gcm', key, iv);
    decipher.setAuthTag(tag);

    // encrypt the given text
    var decrypted = decipher.update(text, 'binary', 'utf8') + decipher.final('utf8');

    return decrypted;
};

module.exports = {
    encrypt: encrypt,
    decrypt: decrypt
}

Java类：主要方法现在只是用于测试，稍后将被删除。

package decryption;

import java.util.Arrays;
import java.util.Base64;

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

public class DecryptAES256 {

    private static String salt;
    private static byte[] ivBase64;
    private static String base64EncryptedText;
    private static String key;

    public static void main(String[] args) {
        String key = "123456789aabbccddeefffffffffffff";
        String sourceText = "Q10blKuyyYozaRf0RVYW7bave8mT5wrJzSdURQQa3lEqEQtgYM3ss825YpCQ70A7hpq5ECPafAxdLMSIBZCxzGbv/Cj4i6W4JCJXuS107rUy0tAAQVQQA2ZhbrQ0gNV9QA==";
        System.out.println(decrypt(key, sourceText));
    }

    public static String decrypt(String masterkey, String encryptedText) {
        byte[] parts = encryptedText.getBytes();
        salt = new String(Arrays.copyOfRange(parts, 0, 64));
        ivBase64 = Arrays.copyOfRange(parts, 64, 76);
        ivBase64 = Base64.getDecoder().decode(ivBase64);
        base64EncryptedText = new String(Arrays.copyOfRange(parts, 76, parts.length));
        key = masterkey;
        byte[] decipheredText = decodeAES_256_CBC();
        return new String(decipheredText);
    }

    private static byte[] decodeAES_256_CBC() {
        try {
            SecretKeySpec skeySpec = new SecretKeySpec(key.getBytes("UTF-8"), "AES");
            Cipher cipher = Cipher.getInstance("AES/GCM/NoPadding");
            byte[] text = base64EncryptedText.getBytes();
            GCMParameterSpec params = new GCMParameterSpec(128, ivBase64, 0, ivBase64.length);
            cipher.init(Cipher.DECRYPT_MODE, skeySpec, params);
            return cipher.doFinal(Base64.getDecoder().decode(text));
        } catch (Exception e) {
            e.printStackTrace();
            throw new RuntimeException("Failed to decrypt");
        }
    }
}

Answer 1

抛出的异常是正常的，您的Java代码中有2个问题：

1-您的AES密钥未正确解码：它以十六进制形式包装，而您将其解码，就好像它不是一样。调用secretkeyspec()时，需要将其从十六进制表示形式转换为字节。

替换以下一行：

SecretKeySpec skeySpec = new SecretKeySpec(key.getBytes("UTF-8"), "AES");

SecretKeySpec skeySpec = new SecretKeySpec(Hex.decodeHex(key.toCharArray()), "AES");

加密和解密的源代码在以下文件中：https://github.com/alexandrefenyo/kif-idp-client/blob/master/src/kif/libfc/Tools.java

请参阅名为encodegcm()和decodegcm()的方法。

这些方法在这里由main类调用：https://github.com/alexandrefenyo/kif-idp-client/blob/master/src/kif/libfc/commandline.java