com.confighub.core.security.Encryption.java Source code

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Here is the source code for com.confighub.core.security.Encryption.java

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/*
 * This file is part of ConfigHub.
 *
 * ConfigHub 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.
 *
 * ConfigHub 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 ConfigHub.If not, see <http://www.gnu.org/licenses/>.
 */

package com.confighub.core.security;

import com.confighub.core.error.ConfigException;
import com.confighub.core.error.Error;
import com.confighub.core.utils.Utils;
import org.apache.commons.codec.binary.Base64;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

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

public class Encryption {
    private static final Logger log = LogManager.getLogger(Encryption.class);

    public static String encrypt(final CipherTransformation ct, final String text, final String secret)
            throws ConfigException {
        try {

            switch (ct.getAlgo()) {
            case "AES":
            case "DES":
            case "DESede":
                return encryptShared(ct, text, secret);

            default:
                throw new ConfigException(Error.Code.ENCRYPTION_ERROR);
            }
        } catch (ConfigException e) {
            throw e;
        } catch (Exception e) {
            throw new ConfigException(Error.Code.DECRYPTION_ERROR);
        }

    }

    public static String decrypt(final CipherTransformation ct, final String text, final String secret)
            throws ConfigException {
        try {
            switch (ct.getAlgo()) {
            case "AES":
            case "DES":
            case "DESede":
                return decryptShared(ct, text, secret);

            default:
                throw new ConfigException(Error.Code.DECRYPTION_ERROR);
            }
        } catch (ConfigException e) {
            throw e;
        } catch (Exception e) {
            throw new ConfigException(Error.Code.DECRYPTION_ERROR);
        }
    }

    //-----------------------------------------------------------------------------------------------
    // DES, DESede, AES
    //-----------------------------------------------------------------------------------------------
    private static byte[] getKeyAsBytes(String key, int len) {
        byte[] bb = new byte[len]; // a Triple DES key is a byte[24] array

        for (int i = 0; i < key.length() && i < bb.length; i++)
            bb[i] = (byte) key.charAt(i);

        return bb;
    }

    private static byte[] getIV(int len) {
        byte[] iv = new byte[len];
        for (int i = 0; i < iv.length; i++)
            iv[i] = 0;
        return iv;
    }

    private static String encryptShared(CipherTransformation ct, String decrypted, String secret)
            throws ConfigException {
        if (null == decrypted)
            return null;

        try {
            Cipher cipher = Cipher.getInstance(ct.getName());
            final int blockSize = cipher.getBlockSize();

            SecretKeySpec sharedKey = new SecretKeySpec(getKeyAsBytes(secret, ct.getKeyLen()), ct.getAlgo());

            if ("CBC".equals(ct.getMode()))
                cipher.init(Cipher.ENCRYPT_MODE, sharedKey, new IvParameterSpec(getIV(blockSize)));
            else
                cipher.init(Cipher.ENCRYPT_MODE, sharedKey);

            byte[] encrypted = cipher.doFinal(Utils.isBlank(decrypted) ? new byte[0] : decrypted.getBytes("UTF8"));
            return Base64.encodeBase64String(encrypted);
        } catch (Exception e) {
            throw new ConfigException(Error.Code.ENCRYPTION_ERROR);
        }
    }

    private static String decryptShared(CipherTransformation ct, String encrypted, String secret)
            throws ConfigException {
        if (null == encrypted)
            return null;

        try {
            Cipher cipher = Cipher.getInstance(ct.getName());
            final int blockSize = cipher.getBlockSize();

            SecretKeySpec sharedKey = new SecretKeySpec(getKeyAsBytes(secret, ct.getKeyLen()), ct.getAlgo());

            if ("CBC".equals(ct.getMode()))
                cipher.init(Cipher.DECRYPT_MODE, sharedKey, new IvParameterSpec(getIV(blockSize)));
            else
                cipher.init(Cipher.DECRYPT_MODE, sharedKey);

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

            return new String(decrypted, "UTF8");
        } catch (Exception e) {
            throw new ConfigException(Error.Code.DECRYPTION_ERROR);
        }
    }
}