[JAVA] Aes 암복호화 소스코드

import org.apache.commons.codec.DecoderException;
import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.binary.Hex;

import javax.crypto.*;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.PBEKeySpec;
import javax.crypto.spec.SecretKeySpec;
import java.nio.charset.StandardCharsets;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.Key;
import java.security.NoSuchAlgorithmException;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.KeySpec;

/**
 * 암/복호화
 * @since 2024.10.24
 */
public class AesUtil {

    private final static String SALT = "CSUZKNWMJAA4ODP8OSWPWIV9VUM8RIR6RABMNFYH6TJ90XUCUN0GFIW5RFC7L0IP";
    private final static String PASSWORD = "MY_PASSWORD_KEY";
    private final static String IV = "7QVRN84YNJJSLHX4N9Y5GPGC0QKSW7HJ";
    private final static String INSTANCE = "PBKDF2WithHmacSHA1";
    private final static String CIPHER_INSTANCE = "AES/CBC/PKCS5Padding";
    private final static String ALGORITHM = "AES";

    /**
     * 암호화
     */
    public static String encrypt(String license) {
        String encryptString = "";
        try {
            Key key = generateKey();
            byte[] encrypted = doFinal(Cipher.ENCRYPT_MODE, key, license.getBytes(StandardCharsets.UTF_8));
            encryptString = new String(Base64.encodeBase64(encrypted));
        } catch (Exception e) {
            throw new IllegalStateException(e);
        }
        return encryptString;
    }

    /**
     * 복호화
     */
    public static String decrypt(String decrypedLicense) {
        String decryptString = "";
        try {
            Key key = generateKey();
            byte[] decrypted = doFinal(Cipher.DECRYPT_MODE, key, Base64.decodeBase64(decrypedLicense));
            decryptString = new String(decrypted, StandardCharsets.UTF_8);
        } catch (Exception e) {
            throw new IllegalStateException(e);
        }
        return decryptString;
    }

    // 키 생성
    private static Key generateKey() throws NoSuchAlgorithmException, InvalidKeySpecException, DecoderException {
        SecretKeyFactory factory = SecretKeyFactory.getInstance(INSTANCE);
        KeySpec spec = new PBEKeySpec(PASSWORD.toCharArray(), hex(SALT), 1000, 128);
        return new SecretKeySpec(factory.generateSecret(spec).getEncoded(), ALGORITHM);
    }

    // 암/복호화 처리
    private static byte[] doFinal(int mode, Key key, byte[] bytes) throws DecoderException
            , IllegalBlockSizeException, BadPaddingException, InvalidAlgorithmParameterException
            , InvalidKeyException, NoSuchPaddingException, NoSuchAlgorithmException {
        Cipher cipher = Cipher.getInstance(CIPHER_INSTANCE);
        cipher.init(mode, key, new IvParameterSpec(hex(IV)));
        return cipher.doFinal(bytes);
    }

    // toHex
    public static byte[] hex(String str) throws DecoderException {
        return Hex.decodeHex(str.toCharArray());
    }
}

 

간만에 끄적이다 만들어서 올려보는 자바 암복호화 소스

여기에 적힌 SALT와 IV는 즉석으로 문자열을 생성해 만든것이므로 어디에도 쓰이는 경우가 없다

참고로 쓰려면 다르게 값을 주는 것이 좋을 수도 있다