AES 128비트 암호화(ECB 모드, PKCS5Padding)

AES 128 비트 암호화 / 복호화

ECB 모드 <-- 중요(CBC 아님)

PKCS5Padding <-- 패딩방식

자바 버전

import javax.crypto.Cipher;

import javax.crypto.spec.SecretKeySpec;

 

import sun.misc.BASE64Decoder;

import sun.misc.BASE64Encoder;

 

public class Aes128 {

    /**

     * 암호화

     *

     * @param input

     * @param key

     * @return

     */

    public static String encrypt(String input, String key) {

        byte[] crypted = null;

        try {

 

            SecretKeySpec skey = new SecretKeySpec(key.getBytes(), "AES");

 

            Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");

            cipher.init(Cipher.ENCRYPT_MODE, skey);

            crypted = cipher.doFinal(input.getBytes());

        } catch(Exception e) {

            System.out.println(e.toString());

        }

 

        BASE64Encoder encoder = new BASE64Encoder();

 

        String str = encoder.encode(crypted);

 

        return new String(str);

    }

 

    /**

     * 복호화

     *

     * @param input

     * @param key

     * @return

     */

    public static String decrypt(String input, String key) {

        byte[] output = null;

        try {

            BASE64Decoder decoder = new BASE64Decoder();

 

            SecretKeySpec skey = new SecretKeySpec(key.getBytes(), "AES");

 

            Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");

            cipher.init(Cipher.DECRYPT_MODE, skey);

            output = cipher.doFinal(decoder.decodeBuffer(input));

 

        } catch(Exception e) {

            System.out.println(e.toString());

        }

        return new String(output);

    }

}

사용 방법

public void aes_enc() throws Exception {

 

    Aes128 aes = new Aes128();

    String key = "0123456789abcdef";

 

    String str = "yangyag";

    String encode = aes.encrypt(str, key);

 

    System.out.println("encode--->" + encode);

}

 

public void aes_dec() throws Exception {

     

    Aes128 aes = new Aes128();

    String key = "0123456789abcdef";

     

    String str = "bcOXU9eLYKadQejOHkjvbg==";

    String decode = aes.decrypt(str, key);

     

    System.out.println("decode--->" + decode);

}

출처: https://yangyag.tistory.com/467 [Hello Brother!]