001/*
002 * jPOS Project [http://jpos.org]
003 * Copyright (C) 2000-2026 jPOS Software SRL
004 *
005 * This program is free software: you can redistribute it and/or modify
006 * it under the terms of the GNU Affero General Public License as
007 * published by the Free Software Foundation, either version 3 of the
008 * License, or (at your option) any later version.
009 *
010 * This program is distributed in the hope that it will be useful,
011 * but WITHOUT ANY WARRANTY; without even the implied warranty of
012 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
013 * GNU Affero General Public License for more details.
014 *
015 * You should have received a copy of the GNU Affero General Public License
016 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
017 */
018
019package org.jpos.core;
020
021import org.jpos.iso.ISOUtil;
022import org.jpos.security.SystemSeed;
023
024import java.nio.ByteBuffer;
025import java.util.Base64;
026
027/** {@link EnvironmentProvider} that resolves {@code obf::} references by deobfuscating the encoded value. */
028public class ObfEnvironmentProvider implements EnvironmentProvider {
029    /** Default constructor; no instance state to initialise. */
030    public ObfEnvironmentProvider() {}
031    @Override
032    public String prefix() {
033        return "obf::";
034    }
035
036    @Override
037    public String get(String config) {
038        ByteBuffer buf = ByteBuffer.wrap(Base64.getDecoder().decode(config));
039        int i = buf.getInt();
040        int l = buf.getInt();
041        byte[] b = new byte[l];
042        buf.get(b);
043        return new String(ISOUtil.xor(b, SystemSeed.getSeed(i, l)));
044    }
045}