Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/**
 * Copyright (C) 2011 Whisper Systems
 * Copyright (C) 2013 Open Whisper Systems
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

import java.security.GeneralSecurityException;

import javax.crypto.Mac;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.PBEKeySpec;

import javax.crypto.spec.SecretKeySpec;

public class Main {
    private static byte[] macWithPassphrase(byte[] macSalt, int iterations, byte[] data, String passphrase)
            throws GeneralSecurityException {
        Mac hmac = getMacForPassphrase(passphrase, macSalt, iterations);
        byte[] mac = hmac.doFinal(data);
        byte[] result = new byte[data.length + mac.length];

        System.arraycopy(data, 0, result, 0, data.length);
        System.arraycopy(mac, 0, result, data.length, mac.length);

        return result;
    }

    private static Mac getMacForPassphrase(String passphrase, byte[] salt, int iterations)
            throws GeneralSecurityException {
        SecretKey key = getKeyFromPassphrase(passphrase, salt, iterations);
        byte[] pbkdf2 = key.getEncoded();
        SecretKeySpec hmacKey = new SecretKeySpec(pbkdf2, "HmacSHA1");
        Mac hmac = Mac.getInstance("HmacSHA1");
        hmac.init(hmacKey);

        return hmac;
    }

    private static SecretKey getKeyFromPassphrase(String passphrase, byte[] salt, int iterations)
            throws GeneralSecurityException {
        PBEKeySpec keyspec = new PBEKeySpec(passphrase.toCharArray(), salt, iterations);
        SecretKeyFactory skf = SecretKeyFactory.getInstance("PBEWITHSHA1AND128BITAES-CBC-BC");
        return skf.generateSecret(keyspec);
    }
}