LoginCrypto.java

/*
 * This file is part of the OdinMS Maple Story Server Copyright (C) 2008 ~ 2010
 * Patrick Huy <patrick.huy@frz.cc> Matthias Butz <matze@odinms.de> Jan
 * Christian Meyer <vimes@odinms.de>
 * 
 * This program is free software: you can redistribute it and/or modify it under
 * the terms of the GNU Affero General Public License version 3 as published by
 * the Free Software Foundation. You may not use, modify or distribute this
 * program under any other version of the GNU Affero General Public License.
 * 
 * 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 Affero General Public License for more
 * details.
 * 
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
package javastory.client;

import java.io.UnsupportedEncodingException;
import java.math.BigInteger;
import java.security.InvalidKeyException;
import java.security.KeyFactory;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import java.security.PrivateKey;
import java.security.Security;
import java.security.spec.RSAPrivateKeySpec;
import java.util.Random;

import javastory.tools.HexTool;

import javax.crypto.Cipher;

import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.bouncycastle.util.encoders.Hex;

public final class LoginCrypto {

	private LoginCrypto() {
	}

	protected final static int extralength = 6;
	private final static char[] ALPHABET = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".toCharArray();
	private final static char[] DIGIT = "123456789".toCharArray();
	private final static Random RNG = new Random();
	private static KeyFactory RSAKeyFactory;

	static {
		Security.addProvider(new BouncyCastleProvider());

		try {
			RSAKeyFactory = KeyFactory.getInstance("RSA");
		} catch (final NoSuchAlgorithmException nsa) {
			System.err.println("[LoginCrypto] Error occured with RSA KeyFactory");
		}
	}

	public static String Generate_13DigitAsiasoftPassport() {
		final StringBuilder sb = new StringBuilder();
		sb.append(ALPHABET[RNG.nextInt(ALPHABET.length)]); // First Letter

		for (int i = 0; i < 11; i++) {
			sb.append(DIGIT[RNG.nextInt(DIGIT.length)]); // 11 Numbers
		}
		sb.append(ALPHABET[RNG.nextInt(ALPHABET.length)]); // Last Letter

		return sb.toString();
	}

	private static String toSimpleHexString(final byte[] bytes) {
		return HexTool.toString(bytes).replace(" ", "").toLowerCase();
	}

	private static String hashWithDigest(final String in, final String digest) {
		try {
			final MessageDigest Digester = MessageDigest.getInstance(digest);
			Digester.update(in.getBytes("US-ASCII"), 0, in.length());
			final byte[] sha1Hash = Digester.digest();
			return toSimpleHexString(sha1Hash);
		} catch (final NoSuchAlgorithmException ex) {
			throw new RuntimeException("Hashing the password failed", ex);
		} catch (final UnsupportedEncodingException e) {
			throw new RuntimeException("Encoding the string failed", e);
		}

	}

	private static String hexSha1(final String in) {
		return hashWithDigest(in, "SHA-1");
	}

	private static String hexSha512(final String in) {
		return hashWithDigest(in, "SHA-512");
	}

	public static boolean checkSha1Hash(final String hash, final String password) {
		return hash.equals(hexSha1(password));
	}

	public static boolean checkSaltedSha512Hash(final String hash, final String password, final String salt) {
		return hash.equals(makeSaltedSha512Hash(password, salt));
	}

	public static String makeSaltedSha512Hash(final String password, final String salt) {
		return hexSha512(password + salt);
	}

	public static String makeSalt() {
		final byte[] salt = new byte[16];
		RNG.nextBytes(salt);
		return toSimpleHexString(salt);
	}

	public static String padWithRandom(final String in) {
		final StringBuilder sb = new StringBuilder();
		for (int i = 0; i < extralength; i++) {
			sb.append(RNG.nextBoolean() ? ALPHABET[RNG.nextInt(ALPHABET.length)] : DIGIT[RNG.nextInt(DIGIT.length)]);
		}
		return sb.toString() + in;
	}

	public static String getPadding(final String in) {
		return in.substring(extralength, extralength + 128);
	}

	public static String decryptRSA(final String EncryptedPassword) {
		try {
			final Cipher cipher = Cipher.getInstance("RSA/NONE/OAEPPadding", "BC");
			final BigInteger modulus = new BigInteger(
				"107657795738756861764863218740655861479186575385923787150128619142132921674398952720882614694082036467689482295621654506166910217557126105160228025353603544726428541751588805629215516978192030682053419499436785335057001573080195806844351954026120773768050428451512387703488216884037312069441551935633523181351");
			final BigInteger privateExponent = new BigInteger(
				"5550691850424331841608142211646492148529402295329912519344562675759756203942720314385192411176941288498447604817211202470939921344057999440566557786743767752684118754789131428284047255370747277972770485804010629706937510833543525825792410474569027516467052693380162536113699974433283374142492196735301185337");
			final RSAPrivateKeySpec privKey1 = new RSAPrivateKeySpec(modulus, privateExponent);
			final PrivateKey privKey = RSAKeyFactory.generatePrivate(privKey1);

			final byte[] bytes = Hex.decode(EncryptedPassword);
			cipher.init(Cipher.DECRYPT_MODE, privKey);
			return new String(cipher.doFinal(bytes));

		} catch (final InvalidKeyException ike) {
			System.err.println("[LoginCrypto] Error initalizing the encryption cipher.  Make sure you're using the Unlimited Strength cryptography jar files.");
		} catch (final NoSuchProviderException nspe) {
			System.err.println("[LoginCrypto] Security provider not found");
		} catch (final Exception e) {
			System.err.println("[LoginCrypto] Error occured with RSA password decryption.");
		}
		return "";
	}
}