org.dizitart.no2.common.util.CryptoUtils Maven / Gradle / Ivy

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/*
 * Copyright (c) 2017-2021 Nitrite 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 org.dizitart.no2.common.util;

import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.PBEKeySpec;
import javax.crypto.spec.SecretKeySpec;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.KeySpec;

/**
 * @since 4.0
 * @author Anindya Chatterjee
 */
public class CryptoUtils {

    public static byte[] getRandomNonce(int numBytes) {
        byte[] nonce = new byte[numBytes];
        new SecureRandom().nextBytes(nonce);
        return nonce;
    }

    public static SecretKey getAESKeyFromPassword(char[] password, byte[] salt)
        throws NoSuchAlgorithmException, InvalidKeySpecException {

        SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA256");
        // iterationCount = 65536
        // keyLength = 256
        KeySpec spec = new PBEKeySpec(password, salt, 65536, 256);
        return new SecretKeySpec(factory.generateSecret(spec).getEncoded(), "AES");
    }
}