java – 加密配置文件中的密码?

我有一个程序从配置文件中读取服务器信息,并希望加密该配置中的密码,该密码可由我的程序读取并解密.

质量要求:

>加密要存储在文件中的明文密码
>解密从我的程序中读取的加密密码

关于我将如何做到这一点的任何建议?我正在考虑编写自己的算法,但我觉得它会非常不安全.

最佳答案
一种简单的方法是在Java中使用基于密码的加密.这允许您使用密码加密和解密文本.

这基本上意味着使用算法“AES / CBC / PKCS5Padding”初始化javax.crypto.Cipher,并使用“PBKDF2WithHmacSHA512”算法从javax.crypto.SecretKeyFactory获取密钥.

这是一个代码示例(更新以替换不太安全的基于MD5的变体):

import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.security.AlgorithmParameters;
import java.security.GeneralSecurityException;
import java.security.NoSuchAlgorithmException;
import java.security.spec.InvalidKeySpecException;
import java.util.Base64;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.PBEKeySpec;
import javax.crypto.spec.SecretKeySpec;

public class ProtectedConfigFile {

    public static void main(String[] args) throws Exception {
        String password = System.getProperty("password");
        if (password == null) {
            throw new IllegalArgumentException("Run with -Dpassword=<password>");
        }

        // The salt (probably) can be stored along with the encrypted data
        byte[] salt = new String("12345678").getBytes();

        // Decreasing this speeds down startup time and can be useful during testing, but it also makes it easier for brute force attackers
        int iterationCount = 40000;
        // Other values give me java.security.InvalidKeyException: Illegal key size or default parameters
        int keyLength = 128;
        SecretKeySpec key = createSecretKey(password.toCharArray(),
                salt, iterationCount, keyLength);

        String originalPassword = "secret";
        System.out.println("Original password: " + originalPassword);
        String encryptedPassword = encrypt(originalPassword, key);
        System.out.println("Encrypted password: " + encryptedPassword);
        String decryptedPassword = decrypt(encryptedPassword, key);
        System.out.println("Decrypted password: " + decryptedPassword);
    }

    private static SecretKeySpec createSecretKey(char[] password, byte[] salt, int iterationCount, int keyLength) throws NoSuchAlgorithmException, InvalidKeySpecException {
        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA512");
        PBEKeySpec keySpec = new PBEKeySpec(password, salt, iterationCount, keyLength);
        SecretKey keyTmp = keyFactory.generateSecret(keySpec);
        return new SecretKeySpec(keyTmp.getEncoded(), "AES");
    }

    private static String encrypt(String property, SecretKeySpec key) throws GeneralSecurityException, UnsupportedEncodingException {
        Cipher pbeCipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        pbeCipher.init(Cipher.ENCRYPT_MODE, key);
        AlgorithmParameters parameters = pbeCipher.getParameters();
        IvParameterSpec ivParameterSpec = parameters.getParameterSpec(IvParameterSpec.class);
        byte[] cryptoText = pbeCipher.doFinal(property.getBytes("UTF-8"));
        byte[] iv = ivParameterSpec.getIV();
        return base64Encode(iv) + ":" + base64Encode(cryptoText);
    }

    private static String base64Encode(byte[] bytes) {
        return Base64.getEncoder().encodeToString(bytes);
    }

    private static String decrypt(String string, SecretKeySpec key) throws GeneralSecurityException, IOException {
        String iv = string.split(":")[0];
        String property = string.split(":")[1];
        Cipher pbeCipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        pbeCipher.init(Cipher.DECRYPT_MODE, key, new IvParameterSpec(base64Decode(iv)));
        return new String(pbeCipher.doFinal(base64Decode(property)), "UTF-8");
    }

    private static byte[] base64Decode(String property) throws IOException {
        return Base64.getDecoder().decode(property);
    }
}

仍然存在一个问题:您应该在哪里存储用于加密密码的密码?您可以将其存储在源文件中并对其进行模糊处理,但再次找到它并不困难.或者,您可以在启动Java进程时将其作为系统属性提供(-DpropertyProtectionPassword = …).

如果您使用KeyStore,同样的问题仍然存在,KeyStore也受密码保护.基本上,您需要在某处拥有一个主密码,而且很难保护.

转载注明原文:java – 加密配置文件中的密码? - 代码日志