Spring, how to encode and decode a String-CodePudding

I am trying to encode a String so I can store it safely in my database. Most password encoders, like bcrypt, can only hash your String, with no way of getting it back (which for a password makes sense), and I want to decode it when I retrieve the information from my database.

I tried using org.springframework.security.crypto.encrypt.Encryptors.queryableText() but the method is deprecated.

Is there any other way to do it?

CodePudding user response：

import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.util.Base64;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.SecretKeySpec;

public class CryptoManager {
    //Key for encryption and decryption
    public static final byte[] KEY =
            {118, 106, 107, 122, 76, 99, 69, 83, 101, 103, 82, 101, 116, 75, 101, 127};

    public static void main(String args[]) {
        String salt = "HELLO";
        String encryptedString = encrypt(salt, "HelloWorld12345");
        System.out.println("Encripted string is "   encryptedString);

        String decryptedString = decrypt(salt, encryptedString);
        System.out.println("Decrypted string is "   decryptedString);

    }

    public static String encrypt(String salt, String plainText) {
        if (plainText == null || plainText.isEmpty()) {
            System.out.println("No data to encrypt!");
            return plainText;
        }
        Cipher cipher = null;
        String encryptedString = "";
        try {
            // Creating a Cipher object
            cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");

            // Creating a secret key from KEY byte array
            final SecretKeySpec secretKey = new SecretKeySpec(KEY, "AES");

            // Initializing a Cipher object
            cipher.init(Cipher.ENCRYPT_MODE, secretKey);

            // Encrypting the plain text string
            byte[] encryptedText = cipher.doFinal(salt.concat(plainText).getBytes());

            // Encoding the encrypted text to Base64
            encryptedString = Base64.getEncoder().encodeToString(encryptedText);

        } catch (NoSuchAlgorithmException | NoSuchPaddingException | InvalidKeyException
                | IllegalBlockSizeException | BadPaddingException ex) {
            System.out.println("Exception caught while encrypting : "   ex);
        }
        return encryptedString;
    }


    public static String decrypt(String salt, String cipherText) {
        if (cipherText == null || cipherText.isEmpty()) {
            System.out.println("No data to decrypt!");
            return cipherText;
        }
        String decryptedString = "";
        Cipher cipher = null;
        try {
            // Creating a Cipher object
            cipher = Cipher.getInstance("AES/ECB/PKCS5PADDING");

            // Creating a secret key from KEY byte array
            final SecretKeySpec secretKey = new SecretKeySpec(KEY, "AES");

            // Initializing a Cipher object
            cipher.init(Cipher.DECRYPT_MODE, secretKey);

            // Decoding from Base64
            byte[] encryptedText = Base64.getDecoder().decode(cipherText.getBytes());

            // Decrypting to plain text
            decryptedString = new String(cipher.doFinal(encryptedText));

        } catch (NoSuchPaddingException | NoSuchAlgorithmException | InvalidKeyException
                | IllegalBlockSizeException | BadPaddingException ex) {
            System.out.println("Exception caught while decrypting : "   ex);
        }
        return decryptedString.replace(salt, "");
    }

}

Check this out for more detail

CodePudding user response：

Since you want to store the data securely in database, what you really need to do is encrypt the data before writing to database from application.

To encrypt/decrypt the data from application you can use Symmetric key algorithm like AES.

To automatically convert this in entity you can add a converter in corresponding column

@Convert(converter = DataEncryptDecryptConverter.class)
@Column(name = "DATA")
private String data;

And the converter

@Converter
@Component
public class DataEncryptDecryptConverter implements AttributeConverter<String, String> {

    @Override
    public String convertToDatabaseColumn(String attribute) {
      // Code to encrypt data
    }

    @Override
    public String convertToEntityAttribute(String dbData) {
     // Code to decrypt data
    }

}