PBSKeygen.java

/*
 * Copyright 2012 Rui Araújo, Luís Fonseca
 *
 * This file is part of Router Keygen.
 *
 * Router Keygen 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.
 * 
 * Router Keygen 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 Router Keygen.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.exobel.routerkeygen.algorithms;

import android.os.Parcel;
import android.os.Parcelable;

import org.exobel.routerkeygen.R;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.List;

/**
 * The link for this algorithm is:
 * http://sviehb.wordpress.com/2011/12/04/prg-eav4202n
 * -default-wpa-key-algorithm/
 *
 * @author Rui Araújo
 */
public class PBSKeygen extends Keygen {

    public static final Parcelable.Creator<PBSKeygen> CREATOR = new Parcelable.Creator<PBSKeygen>() {
        public PBSKeygen createFromParcel(Parcel in) {
            return new PBSKeygen(in);
        }

        public PBSKeygen[] newArray(int size) {
            return new PBSKeygen[size];
        }
    };
    private final static byte[] saltSHA256 = {0x54, 0x45, 0x4F, 0x74, 0x65, 0x6C,
            (byte) 0xB6, (byte) 0xD9, (byte) 0x86, (byte) 0x96, (byte) 0x8D,
            0x34, 0x45, (byte) 0xD2, 0x3B, 0x15, (byte) 0xCA, (byte) 0xAF,
            0x12, (byte) 0x84, 0x02, (byte) 0xAC, 0x56, 0x00, 0x05,
            (byte) 0xCE, 0x20, 0x75, (byte) 0x94, 0x3F, (byte) 0xDC,
            (byte) 0xE8};
    private final static String lookup = "0123456789ABCDEFGHIKJLMNOPQRSTUVWXYZabcdefghikjlmnopqrstuvwxyz";

    public PBSKeygen(String ssid, String mac) {
        super(ssid, mac);
    }

    private PBSKeygen(Parcel in) {
        super(in);
    }

    @Override
    public int getSupportState() {
        final String mac = getMacAddress();
        if (mac.length() != 12)
            return UNSUPPORTED;
        //Support seems to be very rare if it exist at all.
        /*final String ssidEnd = Integer.toHexString(Integer.parseInt(mac
                .substring(6),16) - 5);
		final String ssid = getSsidName();
		if (ssid.substring(4).equalsIgnoreCase(ssidEnd))
			return SUPPORTED;*/
        return UNLIKELY_SUPPORTED;
    }

    @Override
    public List<String> getKeys() {
        MessageDigest md;
        try {
            md = MessageDigest.getInstance("SHA-256");
        } catch (NoSuchAlgorithmException e1) {
            setErrorCode(R.string.msg_nosha256);
            return null;
        }
        final String mac = getMacAddress();
        if (mac.length() != 12) {
            setErrorCode(R.string.msg_errpirelli);
            return null;
        }

        byte[] macHex = new byte[6];
        for (int i = 0; i < 12; i += 2)
            macHex[i / 2] = (byte) ((Character.digit(mac.charAt(i), 16) << 4) + Character
                    .digit(mac.charAt(i + 1), 16));
        macHex[5] -= 5;

        md.reset();
        md.update(saltSHA256);
        md.update(macHex);
        byte[] hash = md.digest();
        StringBuilder key = new StringBuilder();
        for (int i = 0; i < 13; ++i) {
            key.append(lookup.charAt((hash[i] >= 0 ? hash[i] : 256 + hash[i])
                    % lookup.length()));
        }
        addPassword(key.toString());
        return getResults();
    }

}