org.bunkr.core.utils.SimpleAES.java Source code

Introduction

Here is the source code for org.bunkr.core.utils.SimpleAES.java

Source

/**
 * Copyright (c) 2016 Bunkr
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package org.bunkr.core.utils;

import org.bouncycastle.crypto.CryptoException;
import org.bouncycastle.crypto.paddings.PKCS7Padding;
import org.bouncycastle.crypto.paddings.PaddedBufferedBlockCipher;
import org.bouncycastle.crypto.params.KeyParameter;
import org.bouncycastle.crypto.params.ParametersWithIV;
import org.bunkr.core.crypto.CipherBuilder;
import org.bunkr.core.inventory.Algorithms.Encryption;

import java.util.Arrays;

/**
 * Created At: 2015-11-27
 */
public class SimpleAES {
    private static byte[] runAES(Encryption encryptionAlgorithm, boolean doEncrypt, byte[] subject, byte[] key,
            byte[] iv) throws CryptoException {
        // set up padded buffered cipher
        PaddedBufferedBlockCipher cipher = new PaddedBufferedBlockCipher(
                CipherBuilder.buildCipher(encryptionAlgorithm, doEncrypt, key, iv), new PKCS7Padding());

        // init with key and if
        cipher.init(doEncrypt, new ParametersWithIV(new KeyParameter(key), iv));

        // construct output buffer
        byte[] output = new byte[cipher.getOutputSize(subject.length)];

        // process all da bytes
        int cursor = cipher.processBytes(subject, 0, subject.length, output, 0);

        // process the last bytes from the buffer
        cipher.doFinal(output, cursor);
        return output;
    }

    public static byte[] encrypt(Encryption encryptionAlgorithm, byte[] input, byte[] key, byte[] iv)
            throws CryptoException {
        return runAES(encryptionAlgorithm, true, input, key, iv);
    }

    public static byte[] decrypt(Encryption encryptionAlgorithm, byte[] input, byte[] key, byte[] iv)
            throws CryptoException {
        byte[] withPadding = runAES(encryptionAlgorithm, false, input, key, iv);
        int trueLength = input.length;
        while (trueLength > 0 && withPadding[trueLength - 1] == 0x0)
            trueLength--;
        byte[] nonPadded = new byte[trueLength];
        System.arraycopy(withPadding, 0, nonPadded, 0, trueLength);
        Arrays.fill(withPadding, (byte) 0);
        return nonPadded;
    }
}