com.aast.encrypt.EncryptManager.java Source code

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Here is the source code for com.aast.encrypt.EncryptManager.java

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/**
 *
 * Copyright 20XX the original author or authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.aast.encrypt;

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

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;

/**
 * Created by UltimateZero on 5/6/2017.
 */
public class EncryptManager {

    public static String key = "test";

    private static byte[] getKeyFromString(String keyStr)
            throws UnsupportedEncodingException, NoSuchAlgorithmException {
        byte[] key = keyStr.getBytes("UTF-8");
        MessageDigest sha = MessageDigest.getInstance("SHA-1");
        key = sha.digest(key);
        key = Arrays.copyOf(key, 16); // use only first 128 bit
        return key;
    }

    public static String encryptAES(String key, String value) {
        try {
            byte[] keyBytes = getKeyFromString(key);
            IvParameterSpec iv = new IvParameterSpec(keyBytes);
            SecretKeySpec skeySpec = new SecretKeySpec(keyBytes, "AES");

            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
            cipher.init(Cipher.ENCRYPT_MODE, skeySpec, iv);

            byte[] encrypted = cipher.doFinal(value.getBytes());
            //            System.out.println("encrypted string: "
            //                    + Base64.encodeBase64String(encrypted));

            return Base64.encodeBase64String(encrypted);
        } catch (Exception ex) {
            ex.printStackTrace();
        }

        return null;
    }

    public static String decryptAES(String key, String encrypted) {
        try {
            byte[] keyBytes = getKeyFromString(key);
            IvParameterSpec iv = new IvParameterSpec(keyBytes);
            SecretKeySpec skeySpec = new SecretKeySpec(keyBytes, "AES");

            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
            cipher.init(Cipher.DECRYPT_MODE, skeySpec, iv);

            byte[] original = cipher.doFinal(Base64.decodeBase64(encrypted));

            return new String(original);
        } catch (Exception ex) {
            ex.printStackTrace();
        }

        return null;
    }

    public static void setKey(String key) {
        EncryptManager.key = key;
    }
}