AES 암호화/복호화 알고리즘

프로젝트 bulid path에 아래 jar 파일 추가 필요

commons-codec-1.7.jar

0.25MB

 

AES128 클래스를 만든다.

package 패키지명;
 
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;
import org.apache.commons.codec.binary.Base64;
 
public class AES128 {
    private String ips;
    private Key keySpec;
 
    public AES128(String key) {
        try {
            byte[] keyBytes = new byte[16];
            byte[] b = key.getBytes("UTF-8");
            System.arraycopy(b, 0, keyBytes, 0, keyBytes.length);
            SecretKeySpec keySpec = new SecretKeySpec(keyBytes, "AES");
            this.ips = key.substring(0, 16);
            this.keySpec = keySpec;
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
    }
 
    public String encrypt(String str) {
        Cipher cipher;
        try {
            cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
            cipher.init(Cipher.ENCRYPT_MODE, keySpec,
                    new IvParameterSpec(ips.getBytes()));
 
            byte[] encrypted = cipher.doFinal(str.getBytes("UTF-8"));
            String Str = new String(Base64.encodeBase64(encrypted));
 
            return Str;
        } catch (NoSuchAlgorithmException | NoSuchPaddingException
                | InvalidKeyException | InvalidAlgorithmParameterException
                | IllegalBlockSizeException | BadPaddingException
                | UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return null;
    }
 
    public String decrypt(String str) {
        try {
            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
            cipher.init(Cipher.DECRYPT_MODE, keySpec,
                    new IvParameterSpec(ips.getBytes("UTF-8")));
 
            byte[] byteStr = Base64.decodeBase64(str.getBytes());
            String Str = new String(cipher.doFinal(byteStr), "UTF-8");
 
            return Str;
        } catch (NoSuchAlgorithmException | NoSuchPaddingException
                | InvalidKeyException | InvalidAlgorithmParameterException
                | IllegalBlockSizeException | BadPaddingException
                | UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return null;
    }
}

 

호출부분

public class TestJava {
	
	public static void main(String[] args) {
		AES128 aes128 = new AES128("key");
        // 암호화
        String enc = aes128.encrypt("암호화 하려는 값");
		System.out.println(enc);
        
        // 복호화
        System.out.println(aes128.decrypt(enc));
	}
}