package au.net.aba.crypto.provider;

/*
 * $Id: Twofish.java,v 1.6 1999/01/18 05:01:43 leachbj Exp $
 * $Author: leachbj $
 *
 * Copyright (C) 1996-1998 Australian Business Access Pty Ltd.
 * All rights reserved.         
 *       
 * Use, modification, copying and distribution of this software is subject the
 * terms and conditions of the ABA Public Licence. See the file
 * "PUBLIC_LICENCE" for additional information.
 *
 * If you have not received a copy of the Public Licence, you must destroy all
 * copies of this file immediately. 
 *
 * $Source: /aba/CVSROOT/jdk1.1/src/au.net.aba/crypto/provider/Twofish.java,v $
 * $Revision: 1.6 $
 * $Date: 1999/01/18 05:01:43 $
 * $State: Exp $
 */

import javax.crypto.*;
import javax.crypto.spec.*;

import java.security.*;

import java.security.*;
import java.security.spec.*;

import au.net.aba.crypto.spec.*;

/**
 */
public final class Twofish extends BlockCipher
{
	public final static String ident = "$Id: Twofish.java,v 1.6 1999/01/18 05:01:43 leachbj Exp $";

	//====================================
	// Useful constants
	//====================================

	protected static final int	ROUNDS = 16;

	protected static final int	TF_BLOCK_SIZE = 16; // 16bytes = 128bits

	private byte[] buf;		// general purpose block size buffer

	public final static int MAX_KEY_BITS = 256;

	// for computing subkeys
	private final static int SK_STEP = 0x02020202;
	private final static int SK_BUMP = 0x01010101;
	private final static int SK_ROTL = 9;

	// field generator
	private final static int RS_GF_FDBK = 0x14D;

	// Primitive polynomial for GF(256)
	private static final int GF256_FDBK =   0x169;
	private static final int GF256_FDBK_2 = 0x169 / 2;
	private static final int GF256_FDBK_4 = 0x169 / 4;

	// offsets for the various subkeys
	private static final int INPUT_WHITEN = 0;
	private static final int OUTPUT_WHITEN = INPUT_WHITEN+TF_BLOCK_SIZE / 4;
	private static final int ROUND_SUBKEYS = OUTPUT_WHITEN+TF_BLOCK_SIZE/ 4;

	private static final int TOTAL_SUBKEYS = 40;

	/*
	 * SBox data and round subkeys
	 */
	private int[] sBoxKeys;
	private int[] subKeys;
	private int k64Cnt;

	/**
	 * Define the fixed p0/p1 permutations used in keyed S-box lookup.
	 * By changing the following constant definitions, the S-boxes will
	 * automatically get changed in the Twofish engine.
	 */
	private static final int P_00 = 1;
	private static final int P_01 = 0;
	private static final int P_02 = 0;
	private static final int P_03 = P_01 ^ 1;
	private static final int P_04 = 1;

	private static final int P_10 = 0;
	private static final int P_11 = 0;
	private static final int P_12 = 1;
	private static final int P_13 = P_11 ^ 1;
	private static final int P_14 = 0;

	private static final int P_20 = 1;
	private static final int P_21 = 1;
	private static final int P_22 = 0;
	private static final int P_23 = P_21 ^ 1;
	private static final int P_24 = 0;

	private static final int P_30 = 0;
	private static final int P_31 = 1;
	private static final int P_32 = 1;
	private static final int P_33 = P_31 ^ 1;
	private static final int P_34 = 1;

	/** Fixed 8x8 permutation S-boxes */
	private final static byte[][] P = new byte[][] {
	{	// p0
		(byte) 0xA9, (byte) 0x67, (byte) 0xB3, (byte) 0xE8,
		(byte) 0x04, (byte) 0xFD, (byte) 0xA3, (byte) 0x76,
		(byte) 0x9A, (byte) 0x92, (byte) 0x80, (byte) 0x78,
		(byte) 0xE4, (byte) 0xDD, (byte) 0xD1, (byte) 0x38,
		(byte) 0x0D, (byte) 0xC6, (byte) 0x35, (byte) 0x98,
		(byte) 0x18, (byte) 0xF7, (byte) 0xEC, (byte) 0x6C,
		(byte) 0x43, (byte) 0x75, (byte) 0x37, (byte) 0x26,
		(byte) 0xFA, (byte) 0x13, (byte) 0x94, (byte) 0x48,
		(byte) 0xF2, (byte) 0xD0, (byte) 0x8B, (byte) 0x30,
		(byte) 0x84, (byte) 0x54, (byte) 0xDF, (byte) 0x23,
		(byte) 0x19, (byte) 0x5B, (byte) 0x3D, (byte) 0x59,
		(byte) 0xF3, (byte) 0xAE, (byte) 0xA2, (byte) 0x82,
		(byte) 0x63, (byte) 0x01, (byte) 0x83, (byte) 0x2E,
		(byte) 0xD9, (byte) 0x51, (byte) 0x9B, (byte) 0x7C,
		(byte) 0xA6, (byte) 0xEB, (byte) 0xA5, (byte) 0xBE,
		(byte) 0x16, (byte) 0x0C, (byte) 0xE3, (byte) 0x61,
		(byte) 0xC0, (byte) 0x8C, (byte) 0x3A, (byte) 0xF5,
		(byte) 0x73, (byte) 0x2C, (byte) 0x25, (byte) 0x0B,
		(byte) 0xBB, (byte) 0x4E, (byte) 0x89, (byte) 0x6B,
		(byte) 0x53, (byte) 0x6A, (byte) 0xB4, (byte) 0xF1,
		(byte) 0xE1, (byte) 0xE6, (byte) 0xBD, (byte) 0x45,
		(byte) 0xE2, (byte) 0xF4, (byte) 0xB6, (byte) 0x66,
		(byte) 0xCC, (byte) 0x95, (byte) 0x03, (byte) 0x56,
		(byte) 0xD4, (byte) 0x1C, (byte) 0x1E, (byte) 0xD7,
		(byte) 0xFB, (byte) 0xC3, (byte) 0x8E, (byte) 0xB5,
		(byte) 0xE9, (byte) 0xCF, (byte) 0xBF, (byte) 0xBA,
		(byte) 0xEA, (byte) 0x77, (byte) 0x39, (byte) 0xAF,
		(byte) 0x33, (byte) 0xC9, (byte) 0x62, (byte) 0x71,
		(byte) 0x81, (byte) 0x79, (byte) 0x09, (byte) 0xAD,
		(byte) 0x24, (byte) 0xCD, (byte) 0xF9, (byte) 0xD8,
		(byte) 0xE5, (byte) 0xC5, (byte) 0xB9, (byte) 0x4D,
		(byte) 0x44, (byte) 0x08, (byte) 0x86, (byte) 0xE7,
		(byte) 0xA1, (byte) 0x1D, (byte) 0xAA, (byte) 0xED,
		(byte) 0x06, (byte) 0x70, (byte) 0xB2, (byte) 0xD2,
		(byte) 0x41, (byte) 0x7B, (byte) 0xA0, (byte) 0x11,
		(byte) 0x31, (byte) 0xC2, (byte) 0x27, (byte) 0x90,
		(byte) 0x20, (byte) 0xF6, (byte) 0x60, (byte) 0xFF,
		(byte) 0x96, (byte) 0x5C, (byte) 0xB1, (byte) 0xAB,
		(byte) 0x9E, (byte) 0x9C, (byte) 0x52, (byte) 0x1B,
		(byte) 0x5F, (byte) 0x93, (byte) 0x0A, (byte) 0xEF,
		(byte) 0x91, (byte) 0x85, (byte) 0x49, (byte) 0xEE,
		(byte) 0x2D, (byte) 0x4F, (byte) 0x8F, (byte) 0x3B,
		(byte) 0x47, (byte) 0x87, (byte) 0x6D, (byte) 0x46,
		(byte) 0xD6, (byte) 0x3E, (byte) 0x69, (byte) 0x64,
		(byte) 0x2A, (byte) 0xCE, (byte) 0xCB, (byte) 0x2F,
		(byte) 0xFC, (byte) 0x97, (byte) 0x05, (byte) 0x7A,
		(byte) 0xAC, (byte) 0x7F, (byte) 0xD5, (byte) 0x1A,
		(byte) 0x4B, (byte) 0x0E, (byte) 0xA7, (byte) 0x5A,
		(byte) 0x28, (byte) 0x14, (byte) 0x3F, (byte) 0x29,
		(byte) 0x88, (byte) 0x3C, (byte) 0x4C, (byte) 0x02,
		(byte) 0xB8, (byte) 0xDA, (byte) 0xB0, (byte) 0x17,
		(byte) 0x55, (byte) 0x1F, (byte) 0x8A, (byte) 0x7D,
		(byte) 0x57, (byte) 0xC7, (byte) 0x8D, (byte) 0x74,
		(byte) 0xB7, (byte) 0xC4, (byte) 0x9F, (byte) 0x72,
		(byte) 0x7E, (byte) 0x15, (byte) 0x22, (byte) 0x12,
		(byte) 0x58, (byte) 0x07, (byte) 0x99, (byte) 0x34,
		(byte) 0x6E, (byte) 0x50, (byte) 0xDE, (byte) 0x68,
		(byte) 0x65, (byte) 0xBC, (byte) 0xDB, (byte) 0xF8,
		(byte) 0xC8, (byte) 0xA8, (byte) 0x2B, (byte) 0x40,
		(byte) 0xDC, (byte) 0xFE, (byte) 0x32, (byte) 0xA4,
		(byte) 0xCA, (byte) 0x10, (byte) 0x21, (byte) 0xF0,
		(byte) 0xD3, (byte) 0x5D, (byte) 0x0F, (byte) 0x00,
		(byte) 0x6F, (byte) 0x9D, (byte) 0x36, (byte) 0x42,
		(byte) 0x4A, (byte) 0x5E, (byte) 0xC1, (byte) 0xE0
	},
	{	// p1
		(byte) 0x75, (byte) 0xF3, (byte) 0xC6, (byte) 0xF4,
		(byte) 0xDB, (byte) 0x7B, (byte) 0xFB, (byte) 0xC8,
		(byte) 0x4A, (byte) 0xD3, (byte) 0xE6, (byte) 0x6B,
		(byte) 0x45, (byte) 0x7D, (byte) 0xE8, (byte) 0x4B,
		(byte) 0xD6, (byte) 0x32, (byte) 0xD8, (byte) 0xFD,
		(byte) 0x37, (byte) 0x71, (byte) 0xF1, (byte) 0xE1,
		(byte) 0x30, (byte) 0x0F, (byte) 0xF8, (byte) 0x1B,
		(byte) 0x87, (byte) 0xFA, (byte) 0x06, (byte) 0x3F,
		(byte) 0x5E, (byte) 0xBA, (byte) 0xAE, (byte) 0x5B,
		(byte) 0x8A, (byte) 0x00, (byte) 0xBC, (byte) 0x9D,
		(byte) 0x6D, (byte) 0xC1, (byte) 0xB1, (byte) 0x0E,
		(byte) 0x80, (byte) 0x5D, (byte) 0xD2, (byte) 0xD5,
		(byte) 0xA0, (byte) 0x84, (byte) 0x07, (byte) 0x14,
		(byte) 0xB5, (byte) 0x90, (byte) 0x2C, (byte) 0xA3,
		(byte) 0xB2, (byte) 0x73, (byte) 0x4C, (byte) 0x54,
		(byte) 0x92, (byte) 0x74, (byte) 0x36, (byte) 0x51,
		(byte) 0x38, (byte) 0xB0, (byte) 0xBD, (byte) 0x5A,
		(byte) 0xFC, (byte) 0x60, (byte) 0x62, (byte) 0x96,
		(byte) 0x6C, (byte) 0x42, (byte) 0xF7, (byte) 0x10,
		(byte) 0x7C, (byte) 0x28, (byte) 0x27, (byte) 0x8C,
		(byte) 0x13, (byte) 0x95, (byte) 0x9C, (byte) 0xC7,
		(byte) 0x24, (byte) 0x46, (byte) 0x3B, (byte) 0x70,
		(byte) 0xCA, (byte) 0xE3, (byte) 0x85, (byte) 0xCB,
		(byte) 0x11, (byte) 0xD0, (byte) 0x93, (byte) 0xB8,
		(byte) 0xA6, (byte) 0x83, (byte) 0x20, (byte) 0xFF,
		(byte) 0x9F, (byte) 0x77, (byte) 0xC3, (byte) 0xCC,
		(byte) 0x03, (byte) 0x6F, (byte) 0x08, (byte) 0xBF,
		(byte) 0x40, (byte) 0xE7, (byte) 0x2B, (byte) 0xE2,
		(byte) 0x79, (byte) 0x0C, (byte) 0xAA, (byte) 0x82,
		(byte) 0x41, (byte) 0x3A, (byte) 0xEA, (byte) 0xB9,
		(byte) 0xE4, (byte) 0x9A, (byte) 0xA4, (byte) 0x97,
		(byte) 0x7E, (byte) 0xDA, (byte) 0x7A, (byte) 0x17,
		(byte) 0x66, (byte) 0x94, (byte) 0xA1, (byte) 0x1D,
		(byte) 0x3D, (byte) 0xF0, (byte) 0xDE, (byte) 0xB3,
		(byte) 0x0B, (byte) 0x72, (byte) 0xA7, (byte) 0x1C,
		(byte) 0xEF, (byte) 0xD1, (byte) 0x53, (byte) 0x3E,
		(byte) 0x8F, (byte) 0x33, (byte) 0x26, (byte) 0x5F,
		(byte) 0xEC, (byte) 0x76, (byte) 0x2A, (byte) 0x49,
		(byte) 0x81, (byte) 0x88, (byte) 0xEE, (byte) 0x21,
		(byte) 0xC4, (byte) 0x1A, (byte) 0xEB, (byte) 0xD9,
		(byte) 0xC5, (byte) 0x39, (byte) 0x99, (byte) 0xCD,
		(byte) 0xAD, (byte) 0x31, (byte) 0x8B, (byte) 0x01,
		(byte) 0x18, (byte) 0x23, (byte) 0xDD, (byte) 0x1F,
		(byte) 0x4E, (byte) 0x2D, (byte) 0xF9, (byte) 0x48,
		(byte) 0x4F, (byte) 0xF2, (byte) 0x65, (byte) 0x8E,
		(byte) 0x78, (byte) 0x5C, (byte) 0x58, (byte) 0x19,
		(byte) 0x8D, (byte) 0xE5, (byte) 0x98, (byte) 0x57,
		(byte) 0x67, (byte) 0x7F, (byte) 0x05, (byte) 0x64,
		(byte) 0xAF, (byte) 0x63, (byte) 0xB6, (byte) 0xFE,
		(byte) 0xF5, (byte) 0xB7, (byte) 0x3C, (byte) 0xA5,
		(byte) 0xCE, (byte) 0xE9, (byte) 0x68, (byte) 0x44,
		(byte) 0xE0, (byte) 0x4D, (byte) 0x43, (byte) 0x69,
		(byte) 0x29, (byte) 0x2E, (byte) 0xAC, (byte) 0x15,
		(byte) 0x59, (byte) 0xA8, (byte) 0x0A, (byte) 0x9E,
		(byte) 0x6E, (byte) 0x47, (byte) 0xDF, (byte) 0x34,
		(byte) 0x35, (byte) 0x6A, (byte) 0xCF, (byte) 0xDC,
		(byte) 0x22, (byte) 0xC9, (byte) 0xC0, (byte) 0x9B,
		(byte) 0x89, (byte) 0xD4, (byte) 0xED, (byte) 0xAB,
		(byte) 0x12, (byte) 0xA2, (byte) 0x0D, (byte) 0x52,
		(byte) 0xBB, (byte) 0x02, (byte) 0x2F, (byte) 0xA9,
		(byte) 0xD7, (byte) 0x61, (byte) 0x1E, (byte) 0xB4,
		(byte) 0x50, (byte) 0x04, (byte) 0xF6, (byte) 0xC2,
		(byte) 0x16, (byte) 0x25, (byte) 0x86, (byte) 0x56,
		(byte) 0x55, (byte) 0x09, (byte) 0xBE, (byte) 0x91
	}
	};
	final static int b0(int x)
	{
		return x & 0xFF;
	}
	final static int b1(int x)
	{
		return (x >>> 8) & 0xFF;
	}
	final static int b2(int x)
	{
		return (x >>> 16) & 0xFF;
	}
	final static int b3(int x)
	{
		return (x >>> 24) & 0xFF;
	}
	/**
	 * Decrypt the given input starting at the given offset and place
	 * the result in the provided buffer starting at the given offset.
	 * The input will be an exact multiple of our blocksize.
	 */
	protected int decryptBlock(
		byte[] src,
		int srcIndex,
		int len,
		byte[] dst,
		int dstIndex)
	throws BadPaddingException
	{
		if (len != TF_BLOCK_SIZE)
		{
			throw new BadPaddingException("Datasize less than block size.");
		}

		int[] x = new int[TF_BLOCK_SIZE / 4];

		/*
		 * copy in the block, add whitening
		 */
		for (int i = 0; i < TF_BLOCK_SIZE / 4; i++)
		{
			x[i] = src[srcIndex++] & 0xFF
				| (src[srcIndex++] & 0xFF) << 8
				| (src[srcIndex++] & 0xFF) << 16
				| (src[srcIndex++] & 0xFF) << 24;

			x[i] ^= subKeys[OUTPUT_WHITEN + i];
		}

		/*
		 * main Twofish decryption loop
		 */
		for (int i = ROUNDS - 1; i >= 0 ; i--)
		{
			int t0, t1;

			t0 = f32(x[0], sBoxKeys, k64Cnt);
			t1 = f32(x[1] << 8 | x[1] >>> 24, sBoxKeys, k64Cnt);

			x[2] = x[2] << 1 | x[2] >>> 31;

			// PHT, round keys
			x[2] ^= t0 + t1 + subKeys[ROUND_SUBKEYS+2*i];
			x[3] ^= t0 + 2*t1 + subKeys[ROUND_SUBKEYS+2*i+1];

			x[3] = x[3] << 31 | x[3] >>> 1;

			/* swap for next round */
			if (i > 0)
			{
				int tmp;
				tmp = x[0]; x[0] = x[2]; x[2] = tmp;
				tmp = x[1]; x[1] = x[3]; x[3] = tmp;
			}
		}

		/*
		 * copy out the block, with whitening
		 */
		for (int i = 0; i < TF_BLOCK_SIZE / 4; i++)
		{
			x[i] ^= subKeys[INPUT_WHITEN + i];
			dst[dstIndex++] = (byte)b0(x[i]);
			dst[dstIndex++] = (byte)b1(x[i]);
			dst[dstIndex++] = (byte)b2(x[i]);
			dst[dstIndex++] = (byte)b3(x[i]);
		}

		return TF_BLOCK_SIZE;
	}
	/**
	 * Encrypt the given input starting at the given offset and place