Java 간단한 암호화 복호화

간단하게 암호화 복호화 소스

- Apache Commons Codec 라이브러리가 필요
  https://commons.apache.org/proper/commons-codec/download_codec.cgi

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

import java.io.UnsupportedEncodingException;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.Key;
import java.security.NoSuchAlgorithmException;

import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

public class AES256Util {
    private Key keySpec;
    private String iv;
    private String key = "변경하자 키";

    public AES256Util() throws UnsupportedEncodingException {
        iv = this.key.substring(0, 16);
        byte[] keyBytes = new byte[16];
        byte[] b = iv.getBytes("UTF-8");
        int len = b.length;
        if(len > keyBytes.length)
            len = keyBytes.length;
        System.arraycopy(b, 0, keyBytes, 0, len);
        SecretKeySpec keySpec = new SecretKeySpec(keyBytes, "AES");

        this.keySpec = keySpec;
    }

    // 암호화
    public String aesEncode(String str) throws java.io.UnsupportedEncodingException, NoSuchAlgorithmException,
            NoSuchPaddingException, InvalidKeyException, InvalidAlgorithmParameterException,
            IllegalBlockSizeException, BadPaddingException {
        Cipher c = Cipher.getInstance("AES/CBC/PKCS5Padding");
        c.init(Cipher.ENCRYPT_MODE, keySpec, new IvParameterSpec(this.iv.getBytes()));

        byte[] encrypted = c.doFinal(str.getBytes("UTF-8"));
        String enStr = new String(Base64.encodeBase64(encrypted));

        return enStr;
    }

    //복호화
    public String aesDecode(String str) throws java.io.UnsupportedEncodingException, NoSuchAlgorithmException,
            NoSuchPaddingException, InvalidKeyException, InvalidAlgorithmParameterException,
            IllegalBlockSizeException, BadPaddingException {
        Cipher c = Cipher.getInstance("AES/CBC/PKCS5Padding");
        c.init(Cipher.DECRYPT_MODE, keySpec, new IvParameterSpec(this.iv.getBytes("UTF-8")));

        byte[] byteStr = Base64.decodeBase64(str.getBytes());

        return new String(c.doFinal(byteStr),"UTF-8");
    }
}