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	/*
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code 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
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	/*
	*
	* (C) Copyright IBM Corp. 1999 All Rights Reserved.
	* Copyright 1997 The Open Group Research Institute. All rights reserved.
	*/

	package sun.security.krb5.internal.crypto;

	import javax.crypto.Cipher;
	import javax.crypto.spec.SecretKeySpec;
	import javax.crypto.SecretKeyFactory;
	import javax.crypto.SecretKey;
	import java.security.GeneralSecurityException;
	import javax.crypto.spec.IvParameterSpec;
	import sun.security.krb5.KrbCryptoException;
	import java.util.Arrays;
	import sun.security.action.GetPropertyAction;

	public final class Des {

	// RFC 3961 demands that UTF-8 encoding be used in DES's
	// string-to-key function. For historical reasons, some
	// implementations use a locale-specific encoding. Even
	// so, when the client and server use different locales,
	// they must agree on a common value, normally the one
	// used when the password is set/reset.
	//
	// The following system property is provided to perform the
	// string-to-key encoding. When set, the specified charset
	// name is used. Otherwise, the system default charset.

	private final static String CHARSET =
	java.security.AccessController.doPrivileged(
	new GetPropertyAction("sun.security.krb5.msinterop.des.s2kcharset"));

	private static final long[] bad_keys = {
	0x0101010101010101L, 0xfefefefefefefefeL,
	0x1f1f1f1f1f1f1f1fL, 0xe0e0e0e0e0e0e0e0L,
	0x01fe01fe01fe01feL, 0xfe01fe01fe01fe01L,
	0x1fe01fe00ef10ef1L, 0xe01fe01ff10ef10eL,
	0x01e001e001f101f1L, 0xe001e001f101f101L,
	0x1ffe1ffe0efe0efeL, 0xfe1ffe1ffe0efe0eL,
	0x011f011f010e010eL, 0x1f011f010e010e01L,
	0xe0fee0fef1fef1feL, 0xfee0fee0fef1fef1L
	};

	private static final byte[] good_parity = {
	1, 1, 2, 2, 4, 4, 7, 7,
	8, 8, 11, 11, 13, 13, 14, 14,
	16, 16, 19, 19, 21, 21, 22, 22,
	25, 25, 26, 26, 28, 28, 31, 31,
	32, 32, 35, 35, 37, 37, 38, 38,
	41, 41, 42, 42, 44, 44, 47, 47,
	49, 49, 50, 50, 52, 52, 55, 55,
	56, 56, 59, 59, 61, 61, 62, 62,
	64, 64, 67, 67, 69, 69, 70, 70,
	73, 73, 74, 74, 76, 76, 79, 79,
	81, 81, 82, 82, 84, 84, 87, 87,
	88, 88, 91, 91, 93, 93, 94, 94,
	97, 97, 98, 98, 100, 100, 103, 103,
	104, 104, 107, 107, 109, 109, 110, 110,
	112, 112, 115, 115, 117, 117, 118, 118,
	121, 121, 122, 122, 124, 124, 127, 127,
	(byte)128, (byte)128, (byte)131, (byte)131,
	(byte)133, (byte)133, (byte)134, (byte)134,
	(byte)137, (byte)137, (byte)138, (byte)138,
	(byte)140, (byte)140, (byte)143, (byte)143,
	(byte)145, (byte)145, (byte)146, (byte)146,
	(byte)148, (byte)148, (byte)151, (byte)151,
	(byte)152, (byte)152, (byte)155, (byte)155,
	(byte)157, (byte)157, (byte)158, (byte)158,
	(byte)161, (byte)161, (byte)162, (byte)162,
	(byte)164, (byte)164, (byte)167, (byte)167,
	(byte)168, (byte)168, (byte)171, (byte)171,
	(byte)173, (byte)173, (byte)174, (byte)174,
	(byte)176, (byte)176, (byte)179, (byte)179,
	(byte)181, (byte)181, (byte)182, (byte)182,
	(byte)185, (byte)185, (byte)186, (byte)186,
	(byte)188, (byte)188, (byte)191, (byte)191,
	(byte)193, (byte)193, (byte)194, (byte)194,
	(byte)196, (byte)196, (byte)199, (byte)199,
	(byte)200, (byte)200, (byte)203, (byte)203,
	(byte)205, (byte)205, (byte)206, (byte)206,
	(byte)208, (byte)208, (byte)211, (byte)211,
	(byte)213, (byte)213, (byte)214, (byte)214,
	(byte)217, (byte)217, (byte)218, (byte)218,
	(byte)220, (byte)220, (byte)223, (byte)223,
	(byte)224, (byte)224, (byte)227, (byte)227,
	(byte)229, (byte)229, (byte)230, (byte)230,
	(byte)233, (byte)233, (byte)234, (byte)234,
	(byte)236, (byte)236, (byte)239, (byte)239,
	(byte)241, (byte)241, (byte)242, (byte)242,
	(byte)244, (byte)244, (byte)247, (byte)247,
	(byte)248, (byte)248, (byte)251, (byte)251,
	(byte)253, (byte)253, (byte)254, (byte)254
	};

	public static final byte[] set_parity(byte[] key) {
	for (int i=0; i < 8; i++) {
	key[i] = good_parity[key[i] & 0xff];
	}
	return key;
	}

	public static final long set_parity(long key) {
	return octet2long(set_parity(long2octet(key)));
	}

	public static final boolean bad_key(long key) {
	for (int i = 0; i < bad_keys.length; i++) {
	if (bad_keys[i] == key) {
	return true;
	}
	}
	return false;
	}

	public static final boolean bad_key(byte[] key) {
	return bad_key(octet2long(key));
	}

	public static long octet2long(byte[] input) {
	return octet2long(input, 0);
	}

	public static long octet2long(byte[] input, int offset) { //convert a 8-byte to a long
	long result = 0;
	for (int i = 0; i < 8; i++) {
	if (i + offset < input.length) {
	result \|= (((long)input[i + offset]) & 0xffL) << ((7 - i) * 8);
	}
	}
	return result;
	}

	public static byte[] long2octet(long input) {
	byte[] output = new byte[8];
	for (int i = 0; i < 8; i++) {
	output[i] = (byte)((input >>> ((7 - i) * 8)) & 0xffL);
	}
	return output;
	}

	public static void long2octet(long input, byte[] output) {
	long2octet(input, output, 0);
	}

	public static void long2octet(long input, byte[] output, int offset) {
	for (int i = 0; i < 8; i++) {
	if (i + offset < output.length) {
	output[i + offset] =
	(byte)((input >>> ((7 - i) * 8)) & 0xffL);
	}
	}
	}

	/**
	* Creates a DES cipher in Electronic Codebook mode, with no padding.
	* @param input plain text.
	* @param output the buffer for the result.
	* @param key DES the key to encrypt the text.
	* @param ivec initialization vector.
	*
	* @created by Yanni Zhang, Dec 6 99.
	*/
	public static void cbc_encrypt (
	byte[] input,
	byte[] output,
	byte[] key,
	byte[] ivec,
	boolean encrypt) throws KrbCryptoException {

	Cipher cipher = null;

	try {
	cipher = Cipher.getInstance("DES/CBC/NoPadding");
	} catch (GeneralSecurityException e) {
	KrbCryptoException ke = new KrbCryptoException("JCE provider may not be installed. "
	+ e.getMessage());
	ke.initCause(e);
	throw ke;
	}
	IvParameterSpec params = new IvParameterSpec(ivec);
	SecretKeySpec skSpec = new SecretKeySpec(key, "DES");
	try {
	SecretKeyFactory skf = SecretKeyFactory.getInstance("DES");
	// SecretKey sk = skf.generateSecret(skSpec);
	SecretKey sk = (SecretKey) skSpec;
	if (encrypt)
	cipher.init(Cipher.ENCRYPT_MODE, sk, params);
	else
	cipher.init(Cipher.DECRYPT_MODE, sk, params);
	byte[] result;
	result = cipher.doFinal(input);
	System.arraycopy(result, 0, output, 0, result.length);
	} catch (GeneralSecurityException e) {
	KrbCryptoException ke = new KrbCryptoException(e.getMessage());
	ke.initCause(e);
	throw ke;
	}
	}

	/**
	* Generates DES key from the password.
	* @param passwdChars a char[] used to create the key.
	* @return DES key.
	*
	* @modified by Yanni Zhang, Dec 6, 99
	*/
	public static long char_to_key(char[] passwdChars) throws KrbCryptoException {
	long key = 0;
	long octet, octet1, octet2 = 0;
	byte[] cbytes = null;

	// Convert password to byte array
	try {
	if (CHARSET == null) {
	cbytes = (new String(passwdChars)).getBytes();
	} else {
	cbytes = (new String(passwdChars)).getBytes(CHARSET);
	}
	} catch (Exception e) {
	// clear-up sensitive information
	if (cbytes != null) {
	Arrays.fill(cbytes, 0, cbytes.length, (byte) 0);
	}
	KrbCryptoException ce =
	new KrbCryptoException("Unable to convert passwd, " + e);
	ce.initCause(e);
	throw ce;
	}

	// pad data
	byte[] passwdBytes = pad(cbytes);

	byte[] newkey = new byte[8];
	int length = (passwdBytes.length / 8) + (passwdBytes.length % 8 == 0 ? 0 : 1);
	for (int i = 0; i < length; i++) {
	octet = octet2long(passwdBytes, i * 8) & 0x7f7f7f7f7f7f7f7fL;
	if (i % 2 == 1) {
	octet1 = 0;
	for (int j = 0; j < 64; j++) {
	octet1 \|= ((octet & (1L << j)) >>> j) << (63 - j);
	}
	octet = octet1 >>> 1;
	}
	key ^= (octet << 1);
	}
	key = set_parity(key);
	if (bad_key(key)) {
	byte [] temp = long2octet(key);
	temp[7] ^= 0xf0;
	key = octet2long(temp);
	}

	newkey = des_cksum(long2octet(key), passwdBytes, long2octet(key));
	key = octet2long(set_parity(newkey));
	if (bad_key(key)) {
	byte [] temp = long2octet(key);
	temp[7] ^= 0xf0;
	key = octet2long(temp);
	}

	// clear-up sensitive information
	if (cbytes != null) {
	Arrays.fill(cbytes, 0, cbytes.length, (byte) 0);
	}
	if (passwdBytes != null) {
	Arrays.fill(passwdBytes, 0, passwdBytes.length, (byte) 0);
	}

	return key;
	}

	/**
	* Encrypts the message blocks using DES CBC and output the
	* final block of 8-byte ciphertext.
	* @param ivec Initialization vector.
	* @param msg Input message as an byte array.
	* @param key DES key to encrypt the message.
	* @return the last block of ciphertext.
	*
	* @created by Yanni Zhang, Dec 6, 99.
	*/
	public static byte[] des_cksum(byte[] ivec, byte[] msg, byte[] key) throws KrbCryptoException {
	Cipher cipher = null;

	byte[] result = new byte[8];
	try{
	cipher = Cipher.getInstance("DES/CBC/NoPadding");
	} catch (Exception e) {
	KrbCryptoException ke = new KrbCryptoException("JCE provider may not be installed. "
	+ e.getMessage());
	ke.initCause(e);
	throw ke;
	}
	IvParameterSpec params = new IvParameterSpec(ivec);
	SecretKeySpec skSpec = new SecretKeySpec(key, "DES");
	try {
	SecretKeyFactory skf = SecretKeyFactory.getInstance("DES");
	// SecretKey sk = skf.generateSecret(skSpec);
	SecretKey sk = (SecretKey) skSpec;
	cipher.init(Cipher.ENCRYPT_MODE, sk, params);
	for (int i = 0; i < msg.length / 8; i++) {
	result = cipher.doFinal(msg, i * 8, 8);
	cipher.init(Cipher.ENCRYPT_MODE, sk, (new IvParameterSpec(result)));
	}
	}
	catch (GeneralSecurityException e) {
	KrbCryptoException ke = new KrbCryptoException(e.getMessage());
	ke.initCause(e);
	throw ke;
	}
	return result;
	}

	/**
	* Pads the data so that its length is a multiple of 8 bytes.
	* @param data the raw data.
	* @return the data being padded.
	*
	* @created by Yanni Zhang, Dec 6 99. //Kerberos does not use PKCS5 padding.
	*/
	static byte[] pad(byte[] data) {
	int len;
	if (data.length < 8) len = data.length;
	else len = data.length % 8;
	if (len == 0) return data;
	else {
	byte[] padding = new byte[ 8 - len + data.length];
	for (int i = padding.length - 1; i > data.length - 1; i--) {
	padding[i] = 0;
	}
	System.arraycopy(data, 0, padding, 0, data.length);
	return padding;
	}
	}

	// Caller is responsible for clearing password
	public static byte[] string_to_key_bytes(char[] passwdChars)
	throws KrbCryptoException {
	return long2octet(char_to_key(passwdChars));
	}
	}

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