gnu.crypto.cipher.Twofish Maven / Gradle / Ivy
The newest version!
package gnu.crypto.cipher;
// ----------------------------------------------------------------------------
// $Id: Twofish.java,v 1.9 2003/04/28 10:36:08 raif Exp $
//
// Copyright (C) 2001, 2002, 2003, Free Software Foundation, Inc.
//
// This file is part of GNU Crypto.
//
// GNU Crypto 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 2, or (at your option)
// any later version.
//
// GNU Crypto 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 this program; see the file COPYING. If not, write to the
//
// Free Software Foundation Inc.,
// 59 Temple Place - Suite 330,
// Boston, MA 02111-1307
// USA
//
// Linking this library statically or dynamically with other modules is
// making a combined work based on this library. Thus, the terms and
// conditions of the GNU General Public License cover the whole
// combination.
//
// As a special exception, the copyright holders of this library give
// you permission to link this library with independent modules to
// produce an executable, regardless of the license terms of these
// independent modules, and to copy and distribute the resulting
// executable under terms of your choice, provided that you also meet,
// for each linked independent module, the terms and conditions of the
// license of that module. An independent module is a module which is
// not derived from or based on this library. If you modify this
// library, you may extend this exception to your version of the
// library, but you are not obligated to do so. If you do not wish to
// do so, delete this exception statement from your version.
// ----------------------------------------------------------------------------
import gnu.crypto.Registry;
import gnu.crypto.util.Util;
//import java.io.PrintWriter;
import java.security.InvalidKeyException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
/**
* Twofish is a balanced 128-bit Feistel cipher, consisting of 16 rounds. In
* each round, a 64-bit S-box value is computed from 64 bits of the block, and
* this value is xored into the other half of the block. The two half-blocks are
* then exchanged, and the next round begins. Before the first round, all input
* bits are xored with key-dependent "whitening" subkeys, and after the final
* round the output bits are xored with other key-dependent whitening subkeys;
* these subkeys are not used anywhere else in the algorithm.
*
* Twofish is designed by Bruce Schneier, Doug Whiting, John Kelsey, Chris
* Hall, David Wagner and Niels Ferguson.
*
* References:
*
*
*
* @version $Revision: 1.9 $
*/
public final class Twofish extends BaseCipher {
// Debugging methods and variables
// -------------------------------------------------------------------------
// private static final String NAME = "twofish";
private static final boolean DEBUG = false;
private static final int debuglevel = 9;
// private static final PrintWriter err = new PrintWriter(System.out, true);
// private static void debug(String s) {
// err.println(">>> "+NAME+": "+s);
// }
// Constants and variables
// -------------------------------------------------------------------------
private static final int DEFAULT_BLOCK_SIZE = 16; // in bytes
private static final int DEFAULT_KEY_SIZE = 16; // in bytes
private static final int MAX_ROUNDS = 16; // max # rounds (for allocating subkeys)
private static final int ROUNDS = MAX_ROUNDS;
// subkey array indices
private static final int INPUT_WHITEN = 0;
private static final int OUTPUT_WHITEN = INPUT_WHITEN + DEFAULT_BLOCK_SIZE/4;
private static final int ROUND_SUBKEYS = OUTPUT_WHITEN + DEFAULT_BLOCK_SIZE/4;
// private static final int TOTAL_SUBKEYS = ROUND_SUBKEYS + 2*MAX_ROUNDS;
private static final int SK_STEP = 0x02020202;
private static final int SK_BUMP = 0x01010101;
private static final int SK_ROTL = 9;
private static final String[] Pm = new String[] {
// p0
"\uA967\uB3E8\u04FD\uA376\u9A92\u8078\uE4DD\uD138"+
"\u0DC6\u3598\u18F7\uEC6C\u4375\u3726\uFA13\u9448"+
"\uF2D0\u8B30\u8454\uDF23\u195B\u3D59\uF3AE\uA282"+
"\u6301\u832E\uD951\u9B7C\uA6EB\uA5BE\u160C\uE361"+
"\uC08C\u3AF5\u732C\u250B\uBB4E\u896B\u536A\uB4F1"+
"\uE1E6\uBD45\uE2F4\uB666\uCC95\u0356\uD41C\u1ED7"+
"\uFBC3\u8EB5\uE9CF\uBFBA\uEA77\u39AF\u33C9\u6271"+
"\u8179\u09AD\u24CD\uF9D8\uE5C5\uB94D\u4408\u86E7"+
"\uA11D\uAAED\u0670\uB2D2\u417B\uA011\u31C2\u2790"+
"\u20F6\u60FF\u965C\uB1AB\u9E9C\u521B\u5F93\u0AEF"+
"\u9185\u49EE\u2D4F\u8F3B\u4787\u6D46\uD63E\u6964"+
"\u2ACE\uCB2F\uFC97\u057A\uAC7F\uD51A\u4B0E\uA75A"+
"\u2814\u3F29\u883C\u4C02\uB8DA\uB017\u551F\u8A7D"+
"\u57C7\u8D74\uB7C4\u9F72\u7E15\u2212\u5807\u9934"+
"\u6E50\uDE68\u65BC\uDBF8\uC8A8\u2B40\uDCFE\u32A4"+
"\uCA10\u21F0\uD35D\u0F00\u6F9D\u3642\u4A5E\uC1E0",
// p1
"\u75F3\uC6F4\uDB7B\uFBC8\u4AD3\uE66B\u457D\uE84B"+
"\uD632\uD8FD\u3771\uF1E1\u300F\uF81B\u87FA\u063F"+
"\u5EBA\uAE5B\u8A00\uBC9D\u6DC1\uB10E\u805D\uD2D5"+
"\uA084\u0714\uB590\u2CA3\uB273\u4C54\u9274\u3651"+
"\u38B0\uBD5A\uFC60\u6296\u6C42\uF710\u7C28\u278C"+
"\u1395\u9CC7\u2446\u3B70\uCAE3\u85CB\u11D0\u93B8"+
"\uA683\u20FF\u9F77\uC3CC\u036F\u08BF\u40E7\u2BE2"+
"\u790C\uAA82\u413A\uEAB9\uE49A\uA497\u7EDA\u7A17"+
"\u6694\uA11D\u3DF0\uDEB3\u0B72\uA71C\uEFD1\u533E"+
"\u8F33\u265F\uEC76\u2A49\u8188\uEE21\uC41A\uEBD9"+
"\uC539\u99CD\uAD31\u8B01\u1823\uDD1F\u4E2D\uF948"+
"\u4FF2\u658E\u785C\u5819\u8DE5\u9857\u677F\u0564"+
"\uAF63\uB6FE\uF5B7\u3CA5\uCEE9\u6844\uE04D\u4369"+
"\u292E\uAC15\u59A8\u0A9E\u6E47\uDF34\u356A\uCFDC"+
"\u22C9\uC09B\u89D4\uEDAB\u12A2\u0D52\uBB02\u2FA9"+
"\uD761\u1EB4\u5004\uF6C2\u1625\u8656\u5509\uBE91"
};
/** Fixed 8x8 permutation S-boxes */
private static final byte[][] P = new byte[2][256]; // blank final
/**
* 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;
/** 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;
/** MDS matrix */
private static final int[][] MDS = new int[4][256]; // blank final
private static final int RS_GF_FDBK = 0x14D; // field generator
/**
* KAT vector (from ecb_vk):
* I=183
* KEY=0000000000000000000000000000000000000000000002000000000000000000
* CT=F51410475B33FBD3DB2117B5C17C82D4
*/
private static final byte[] KAT_KEY =
Util.toBytesFromString("0000000000000000000000000000000000000000000002000000000000000000");
private static final byte[] KAT_CT =
Util.toBytesFromString("F51410475B33FBD3DB2117B5C17C82D4");
/** caches the result of the correctness test, once executed. */
private static Boolean valid;
// Static code - to intialise the MDS matrix and lookup tables -------------
static {
long time = System.currentTimeMillis();
// expand the P arrays
int i;
char c;
for (i = 0; i < 256; i++) {
c = Pm[0].charAt(i >>> 1);
P[0][i] = (byte)((i & 1) == 0 ? c >>> 8 : c);
c = Pm[1].charAt(i >>> 1);
P[1][i] = (byte)((i & 1) == 0 ? c >>> 8 : c);
}
// precompute the MDS matrix
int[] m1 = new int[2];
int[] mX = new int[2];
int[] mY = new int[2];
int j;
for (i = 0; i < 256; i++) {
j = P[0][i] & 0xFF; // compute all the matrix elements
m1[0] = j;
mX[0] = Mx_X( j ) & 0xFF;
mY[0] = Mx_Y( j ) & 0xFF;
j = P[1][i] & 0xFF;
m1[1] = j;
mX[1] = Mx_X( j ) & 0xFF;
mY[1] = Mx_Y( j ) & 0xFF;
MDS[0][i] = m1[P_00] << 0 | // fill matrix w/ above elements
mX[P_00] << 8 |
mY[P_00] << 16 |
mY[P_00] << 24;
MDS[1][i] = mY[P_10] << 0 |
mY[P_10] << 8 |
mX[P_10] << 16 |
m1[P_10] << 24;
MDS[2][i] = mX[P_20] << 0 |
mY[P_20] << 8 |
m1[P_20] << 16 |
mY[P_20] << 24;
MDS[3][i] = mX[P_30] << 0 |
m1[P_30] << 8 |
mY[P_30] << 16 |
mX[P_30] << 24;
}
time = System.currentTimeMillis() - time;
if (DEBUG && debuglevel > 8) {
System.out.println("==========");
System.out.println();
System.out.println("Static Data");
System.out.println();
System.out.println("MDS[0][]:");
for (i = 0;i < 64; i++) {
for(j = 0; j < 4; j++) {
System.out.print("0x"+Util.toString(MDS[0][i*4+j])+", ");
}
System.out.println();
}
System.out.println();
System.out.println("MDS[1][]:");
for (i = 0;i < 64; i++) {
for(j = 0; j < 4; j++) {
System.out.print("0x"+Util.toString(MDS[1][i*4+j])+", ");
}
System.out.println();
}
System.out.println();
System.out.println("MDS[2][]:");
for (i = 0;i < 64; i++) {
for(j = 0; j < 4; j++) {
System.out.print("0x"+Util.toString(MDS[2][i*4+j])+", ");
}
System.out.println();
}
System.out.println();
System.out.println("MDS[3][]:");
for (i = 0;i < 64; i++) {
for(j = 0; j < 4; j++) {
System.out.print("0x"+Util.toString(MDS[3][i*4+j])+", ");
}
System.out.println();
}
System.out.println();
System.out.println("Total initialization time: "+time+" ms.");
System.out.println();
}
}
private static final int LFSR1(int x) {
return (x >> 1) ^ ((x & 0x01) != 0 ? GF256_FDBK_2 : 0);
}
private static final int LFSR2(int x) {
return (x >> 2) ^
((x & 0x02) != 0 ? GF256_FDBK_2 : 0) ^
((x & 0x01) != 0 ? GF256_FDBK_4 : 0);
}
// private static final int Mx_1(int x) {
// return x;
// }
private static final int Mx_X(int x) { // 5B
return x ^ LFSR2(x);
}
private static final int Mx_Y(int x) { // EF
return x ^ LFSR1(x) ^ LFSR2(x);
}
// Constructor(s)
// -------------------------------------------------------------------------
/** Trivial 0-arguments constructor. */
public Twofish() {
super(Registry.TWOFISH_CIPHER, DEFAULT_BLOCK_SIZE, DEFAULT_KEY_SIZE);
}
// Class methods
// -------------------------------------------------------------------------
private static final int b0(int x) {
return x & 0xFF;
}
private static final int b1(int x) {
return (x >>> 8) & 0xFF;
}
private static final int b2(int x) {
return (x >>> 16) & 0xFF;
}
private static final int b3(int x) {
return (x >>> 24) & 0xFF;
}
/**
* Use (12, 8) Reed-Solomon code over GF(256) to produce a key S-box 32-bit
* entity from two key material 32-bit entities.
*
* @param k0 1st 32-bit entity.
* @param k1 2nd 32-bit entity.
* @return remainder polynomial generated using RS code
*/
private static final int RS_MDS_Encode(int k0, int k1) {
int r = k1;
int i;
for (i = 0; i < 4; i++) { // shift 1 byte at a time
r = RS_rem(r);
}
r ^= k0;
for (i = 0; i < 4; i++) {
r = RS_rem(r);
}
return r;
}
/**
* Reed-Solomon code parameters: (12, 8) reversible code:
*
* g(x) = x**4 + (a + 1/a) x**3 + a x**2 + (a + 1/a) x + 1
*
* where a = primitive root of field generator 0x14D
*/
private static final int RS_rem(int x) {
int b = (x >>> 24) & 0xFF;
int g2 = ((b << 1) ^ ( (b & 0x80) != 0 ? RS_GF_FDBK : 0 )) & 0xFF;
int g3 = (b >>> 1) ^ ( (b & 0x01) != 0 ? (RS_GF_FDBK >>> 1) : 0 ) ^ g2 ;
int result = (x << 8) ^ (g3 << 24) ^ (g2 << 16) ^ (g3 << 8) ^ b;
return result;
}
private static final int F32(int k64Cnt, int x, int[] k32) {
int b0 = b0(x);
int b1 = b1(x);
int b2 = b2(x);
int b3 = b3(x);
int k0 = k32[0];
int k1 = k32[1];
int k2 = k32[2];
int k3 = k32[3];
int result = 0;
switch (k64Cnt & 3) {
case 1:
result =
MDS[0][(P[P_01][b0] & 0xFF) ^ b0(k0)] ^
MDS[1][(P[P_11][b1] & 0xFF) ^ b1(k0)] ^
MDS[2][(P[P_21][b2] & 0xFF) ^ b2(k0)] ^
MDS[3][(P[P_31][b3] & 0xFF) ^ b3(k0)];
break;
case 0: // same as 4
b0 = (P[P_04][b0] & 0xFF) ^ b0(k3);
b1 = (P[P_14][b1] & 0xFF) ^ b1(k3);
b2 = (P[P_24][b2] & 0xFF) ^ b2(k3);
b3 = (P[P_34][b3] & 0xFF) ^ b3(k3);
case 3:
b0 = (P[P_03][b0] & 0xFF) ^ b0(k2);
b1 = (P[P_13][b1] & 0xFF) ^ b1(k2);
b2 = (P[P_23][b2] & 0xFF) ^ b2(k2);
b3 = (P[P_33][b3] & 0xFF) ^ b3(k2);
case 2: // 128-bit keys (optimize for this case)
result =
MDS[0][(P[P_01][(P[P_02][b0] & 0xFF) ^ b0(k1)] & 0xFF) ^ b0(k0)] ^
MDS[1][(P[P_11][(P[P_12][b1] & 0xFF) ^ b1(k1)] & 0xFF) ^ b1(k0)] ^
MDS[2][(P[P_21][(P[P_22][b2] & 0xFF) ^ b2(k1)] & 0xFF) ^ b2(k0)] ^
MDS[3][(P[P_31][(P[P_32][b3] & 0xFF) ^ b3(k1)] & 0xFF) ^ b3(k0)];
break;
}
return result;
}
private static final int Fe32(int[] sBox, int x, int R) {
return sBox[ 2*_b(x, R ) ] ^
sBox[ 2*_b(x, R+1) + 1] ^
sBox[0x200 + 2*_b(x, R+2) ] ^
sBox[0x200 + 2*_b(x, R+3) + 1];
}
private static final int _b(int x, int N) {
// int result = 0;
// switch (N%4) {
// case 0: result = b0(x); break;
// case 1: result = b1(x); break;
// case 2: result = b2(x); break;
// case 3: result = b3(x); break;
// }
// return result;
// profiling shows that the code spends too long in this method.
// following constructs seem to improve, albeit marginally, performance
switch (N%4) {
case 0: return x & 0xFF;
case 1: return (x >>> 8) & 0xFF;
case 2: return (x >>> 16) & 0xFF;
default: return x >>> 24;
}
}
// Instance methods
// -------------------------------------------------------------------------
// java.lang.Cloneable interface implementation ----------------------------
public Object clone() {
Twofish result = new Twofish();
result.currentBlockSize = this.currentBlockSize;
return result;
}
// IBlockCipherSpi interface implementation --------------------------------
public Iterator blockSizes() {
ArrayList al = new ArrayList();
al.add(new Integer(DEFAULT_BLOCK_SIZE));
return Collections.unmodifiableList(al).iterator();
}
public Iterator keySizes() {
ArrayList al = new ArrayList();
al.add(new Integer(8)); // 64-bit
al.add(new Integer(16)); // 128-bit
al.add(new Integer(24)); // 192-bit
al.add(new Integer(32)); // 256-bit
return Collections.unmodifiableList(al).iterator();
}
/**
* Expands a user-supplied key material into a session key for a designated
* block size.
*
* @param k the 64/128/192/256-bit user-key to use.
* @param bs the desired block size in bytes.
* @return an Object encapsulating the session key.
* @exception IllegalArgumentException if the block size is not 16 (128-bit).
* @exception InvalidKeyException if the key data is invalid.
*/
public Object makeKey(byte[] k, int bs) throws InvalidKeyException {
if (bs != DEFAULT_BLOCK_SIZE) {
throw new IllegalArgumentException();
}
if (k == null) {
throw new InvalidKeyException("Empty key");
}
int length = k.length;
if (!(length == 8 || length == 16 || length == 24 || length == 32)) {
throw new InvalidKeyException("Incorrect key length");
}
int k64Cnt = length / 8;
int subkeyCnt = ROUND_SUBKEYS + 2*ROUNDS;
int[] k32e = new int[4]; // even 32-bit entities
int[] k32o = new int[4]; // odd 32-bit entities
int[] sBoxKey = new int[4];
//
// split user key material into even and odd 32-bit entities and
// compute S-box keys using (12, 8) Reed-Solomon code over GF(256)
//
int i, j, offset = 0;
for (i = 0, j = k64Cnt-1; i < 4 && offset < length; i++, j--) {
k32e[i] = (k[offset++] & 0xFF) |
(k[offset++] & 0xFF) << 8 |
(k[offset++] & 0xFF) << 16 |
(k[offset++] & 0xFF) << 24;
k32o[i] = (k[offset++] & 0xFF) |
(k[offset++] & 0xFF) << 8 |
(k[offset++] & 0xFF) << 16 |
(k[offset++] & 0xFF) << 24;
sBoxKey[j] = RS_MDS_Encode(k32e[i], k32o[i]); // reverse order
}
// compute the round decryption subkeys for PHT. these same subkeys
// will be used in encryption but will be applied in reverse order.
int q, A, B;
int[] subKeys = new int[subkeyCnt];
for (i = q = 0; i < subkeyCnt/2; i++, q += SK_STEP) {
A = F32(k64Cnt, q , k32e); // A uses even key entities
B = F32(k64Cnt, q+SK_BUMP, k32o); // B uses odd key entities
B = B << 8 | B >>> 24;
A += B;
subKeys[2*i ] = A; // combine with a PHT
A += B;
subKeys[2*i + 1] = A << SK_ROTL | A >>> (32-SK_ROTL);
}
// fully expand the table for speed
int k0 = sBoxKey[0];
int k1 = sBoxKey[1];
int k2 = sBoxKey[2];
int k3 = sBoxKey[3];
int b0, b1, b2, b3;
int[] sBox = new int[4 * 256];
for (i = 0; i < 256; i++) {
b0 = b1 = b2 = b3 = i;
switch (k64Cnt & 3) {
case 1:
sBox[ 2*i ] = MDS[0][(P[P_01][b0] & 0xFF) ^ b0(k0)];
sBox[ 2*i+1] = MDS[1][(P[P_11][b1] & 0xFF) ^ b1(k0)];
sBox[0x200+2*i ] = MDS[2][(P[P_21][b2] & 0xFF) ^ b2(k0)];
sBox[0x200+2*i+1] = MDS[3][(P[P_31][b3] & 0xFF) ^ b3(k0)];
break;
case 0: // same as 4
b0 = (P[P_04][b0] & 0xFF) ^ b0(k3);
b1 = (P[P_14][b1] & 0xFF) ^ b1(k3);
b2 = (P[P_24][b2] & 0xFF) ^ b2(k3);
b3 = (P[P_34][b3] & 0xFF) ^ b3(k3);
case 3:
b0 = (P[P_03][b0] & 0xFF) ^ b0(k2);
b1 = (P[P_13][b1] & 0xFF) ^ b1(k2);
b2 = (P[P_23][b2] & 0xFF) ^ b2(k2);
b3 = (P[P_33][b3] & 0xFF) ^ b3(k2);
case 2: // 128-bit keys
sBox[ 2*i ] = MDS[0][(P[P_01][(P[P_02][b0] & 0xFF) ^ b0(k1)] & 0xFF) ^ b0(k0)];
sBox[ 2*i+1] = MDS[1][(P[P_11][(P[P_12][b1] & 0xFF) ^ b1(k1)] & 0xFF) ^ b1(k0)];
sBox[0x200+2*i ] = MDS[2][(P[P_21][(P[P_22][b2] & 0xFF) ^ b2(k1)] & 0xFF) ^ b2(k0)];
sBox[0x200+2*i+1] = MDS[3][(P[P_31][(P[P_32][b3] & 0xFF) ^ b3(k1)] & 0xFF) ^ b3(k0)];
}
}
if (DEBUG && debuglevel > 7) {
System.out.println("S-box[]:");
for (i = 0; i < 64; i++) {
for (j = 0; j < 4; j++) {
System.out.print("0x"+Util.toString(sBox[i*4+j])+", ");
}
System.out.println();
}
System.out.println();
for (i = 0; i < 64; i++) {
for (j = 0; j < 4; j++) {
System.out.print("0x"+Util.toString(sBox[256+i*4+j])+", ");
}
System.out.println();
}
System.out.println();
for (i = 0; i < 64; i++) {
for (j = 0; j < 4; j++) {
System.out.print("0x"+Util.toString(sBox[512+i*4+j])+", ");
}
System.out.println();
}
System.out.println();
for (i = 0; i < 64; i++) {
for (j = 0; j < 4; j++) {
System.out.print("0x"+Util.toString(sBox[768+i*4+j])+", ");
}
System.out.println();
}
System.out.println();
System.out.println("User (odd, even) keys --> S-Box keys:");
for (i = 0; i < k64Cnt; i++) {
System.out.println("0x"+Util.toString(k32o[i])
+" 0x"+Util.toString(k32e[i])
+" --> 0x"+Util.toString(sBoxKey[k64Cnt-1-i]));
}
System.out.println();
System.out.println("Round keys:");
for (i = 0; i < ROUND_SUBKEYS + 2*ROUNDS; i += 2) {
System.out.println("0x"+Util.toString(subKeys[i])
+" 0x"+Util.toString(subKeys[i+1]));
}
System.out.println();
}
return new Object[] {sBox, subKeys};
}
public void encrypt(byte[] in, int inOffset, byte[] out, int outOffset,
Object sessionKey, int bs) {
if (bs != DEFAULT_BLOCK_SIZE) {
throw new IllegalArgumentException();
}
Object[] sk = (Object[]) sessionKey; // extract S-box and session key
int[] sBox = (int[]) sk[0];
int[] sKey = (int[]) sk[1];
if (DEBUG && debuglevel > 6) {
System.out.println("PT="+Util.toString(in, inOffset, bs));
}
int x0 = (in[inOffset++] & 0xFF) |
(in[inOffset++] & 0xFF) << 8 |
(in[inOffset++] & 0xFF) << 16 |
(in[inOffset++] & 0xFF) << 24;
int x1 = (in[inOffset++] & 0xFF) |
(in[inOffset++] & 0xFF) << 8 |
(in[inOffset++] & 0xFF) << 16 |
(in[inOffset++] & 0xFF) << 24;
int x2 = (in[inOffset++] & 0xFF) |
(in[inOffset++] & 0xFF) << 8 |
(in[inOffset++] & 0xFF) << 16 |
(in[inOffset++] & 0xFF) << 24;
int x3 = (in[inOffset++] & 0xFF) |
(in[inOffset++] & 0xFF) << 8 |
(in[inOffset++] & 0xFF) << 16 |
(in[inOffset++] & 0xFF) << 24;
x0 ^= sKey[INPUT_WHITEN ];
x1 ^= sKey[INPUT_WHITEN + 1];
x2 ^= sKey[INPUT_WHITEN + 2];
x3 ^= sKey[INPUT_WHITEN + 3];
if (DEBUG && debuglevel > 6) {
System.out.println("PTw="
+Util.toString(x0)+Util.toString(x1)
+Util.toString(x2)+Util.toString(x3));
}
int t0, t1;
int k = ROUND_SUBKEYS;
for (int R = 0; R < ROUNDS; R += 2) {
t0 = Fe32(sBox, x0, 0);
t1 = Fe32(sBox, x1, 3);
x2 ^= t0 + t1 + sKey[k++];
x2 = x2 >>> 1 | x2 << 31;
x3 = x3 << 1 | x3 >>> 31;
x3 ^= t0 + 2*t1 + sKey[k++];
if (DEBUG && debuglevel > 6) {
System.out.println("CT"+(R)+"="
+Util.toString(x0)+Util.toString(x1)
+Util.toString(x2)+Util.toString(x3));
}
t0 = Fe32(sBox, x2, 0);
t1 = Fe32(sBox, x3, 3);
x0 ^= t0 + t1 + sKey[k++];
x0 = x0 >>> 1 | x0 << 31;
x1 = x1 << 1 | x1 >>> 31;
x1 ^= t0 + 2*t1 + sKey[k++];
if (DEBUG && debuglevel > 6) {
System.out.println("CT"+(R+1)+"="
+Util.toString(x0)+Util.toString(x1)
+Util.toString(x2)+Util.toString(x3));
}
}
x2 ^= sKey[OUTPUT_WHITEN ];
x3 ^= sKey[OUTPUT_WHITEN + 1];
x0 ^= sKey[OUTPUT_WHITEN + 2];
x1 ^= sKey[OUTPUT_WHITEN + 3];
if (DEBUG && debuglevel > 6) {
System.out.println("CTw="
+Util.toString(x0)+Util.toString(x1)
+Util.toString(x2)+Util.toString(x3));
}
out[outOffset++] = (byte) x2;
out[outOffset++] = (byte)(x2 >>> 8);
out[outOffset++] = (byte)(x2 >>> 16);
out[outOffset++] = (byte)(x2 >>> 24);
out[outOffset++] = (byte) x3;
out[outOffset++] = (byte)(x3 >>> 8);
out[outOffset++] = (byte)(x3 >>> 16);
out[outOffset++] = (byte)(x3 >>> 24);
out[outOffset++] = (byte) x0;
out[outOffset++] = (byte)(x0 >>> 8);
out[outOffset++] = (byte)(x0 >>> 16);
out[outOffset++] = (byte)(x0 >>> 24);
out[outOffset++] = (byte) x1;
out[outOffset++] = (byte)(x1 >>> 8);
out[outOffset++] = (byte)(x1 >>> 16);
out[outOffset ] = (byte)(x1 >>> 24);
if (DEBUG && debuglevel > 6) {
System.out.println("CT="+Util.toString(out, outOffset-15, 16));
System.out.println();
}
}
public void decrypt(byte[] in, int inOffset, byte[] out, int outOffset,
Object sessionKey, int bs) {
if (bs != DEFAULT_BLOCK_SIZE) {
throw new IllegalArgumentException();
}
Object[] sk = (Object[]) sessionKey; // extract S-box and session key
int[] sBox = (int[]) sk[0];
int[] sKey = (int[]) sk[1];
if (DEBUG && debuglevel > 6) {
System.out.println("CT="+Util.toString(in, inOffset, bs));
}
int x2 = (in[inOffset++] & 0xFF) |
(in[inOffset++] & 0xFF) << 8 |
(in[inOffset++] & 0xFF) << 16 |
(in[inOffset++] & 0xFF) << 24;
int x3 = (in[inOffset++] & 0xFF) |
(in[inOffset++] & 0xFF) << 8 |
(in[inOffset++] & 0xFF) << 16 |
(in[inOffset++] & 0xFF) << 24;
int x0 = (in[inOffset++] & 0xFF) |
(in[inOffset++] & 0xFF) << 8 |
(in[inOffset++] & 0xFF) << 16 |
(in[inOffset++] & 0xFF) << 24;
int x1 = (in[inOffset++] & 0xFF) |
(in[inOffset++] & 0xFF) << 8 |
(in[inOffset++] & 0xFF) << 16 |
(in[inOffset++] & 0xFF) << 24;
x2 ^= sKey[OUTPUT_WHITEN ];
x3 ^= sKey[OUTPUT_WHITEN + 1];
x0 ^= sKey[OUTPUT_WHITEN + 2];
x1 ^= sKey[OUTPUT_WHITEN + 3];
if (DEBUG && debuglevel > 6) {
System.out.println("CTw="
+Util.toString(x2)+Util.toString(x3)
+Util.toString(x0)+Util.toString(x1));
}
int k = ROUND_SUBKEYS + 2*ROUNDS - 1;
int t0, t1;
for (int R = 0; R < ROUNDS; R += 2) {
t0 = Fe32(sBox, x2, 0);
t1 = Fe32(sBox, x3, 3);
x1 ^= t0 + 2*t1 + sKey[k--];
x1 = x1 >>> 1 | x1 << 31;
x0 = x0 << 1 | x0 >>> 31;
x0 ^= t0 + t1 + sKey[k--];
if (DEBUG && debuglevel > 6) {
System.out.println("PT"+(ROUNDS-R)+"="
+Util.toString(x2)+Util.toString(x3)
+Util.toString(x0)+Util.toString(x1));
}
t0 = Fe32(sBox, x0, 0);
t1 = Fe32(sBox, x1, 3);
x3 ^= t0 + 2*t1 + sKey[k--];
x3 = x3 >>> 1 | x3 << 31;
x2 = x2 << 1 | x2 >>> 31;
x2 ^= t0 + t1 + sKey[k--];
if (DEBUG && debuglevel > 6) {
System.out.println("PT"+(ROUNDS-R-1)+"="+
Util.toString(x2)+Util.toString(x3)+
Util.toString(x0)+Util.toString(x1));
}
}
x0 ^= sKey[INPUT_WHITEN ];
x1 ^= sKey[INPUT_WHITEN + 1];
x2 ^= sKey[INPUT_WHITEN + 2];
x3 ^= sKey[INPUT_WHITEN + 3];
if (DEBUG && debuglevel > 6) {
System.out.println("PTw="
+Util.toString(x2)+Util.toString(x3)
+Util.toString(x0)+Util.toString(x1));
}
out[outOffset++] = (byte) x0;
out[outOffset++] = (byte)(x0 >>> 8);
out[outOffset++] = (byte)(x0 >>> 16);
out[outOffset++] = (byte)(x0 >>> 24);
out[outOffset++] = (byte) x1;
out[outOffset++] = (byte)(x1 >>> 8);
out[outOffset++] = (byte)(x1 >>> 16);
out[outOffset++] = (byte)(x1 >>> 24);
out[outOffset++] = (byte) x2;
out[outOffset++] = (byte)(x2 >>> 8);
out[outOffset++] = (byte)(x2 >>> 16);
out[outOffset++] = (byte)(x2 >>> 24);
out[outOffset++] = (byte) x3;
out[outOffset++] = (byte)(x3 >>> 8);
out[outOffset++] = (byte)(x3 >>> 16);
out[outOffset ] = (byte)(x3 >>> 24);
if (DEBUG && debuglevel > 6) {
System.out.println("PT="+Util.toString(out, outOffset-15, 16));
System.out.println();
}
}
public boolean selfTest() {
if (valid == null) {
boolean result = super.selfTest(); // do symmetry tests
if (result) {
result = testKat(KAT_KEY, KAT_CT);
}
valid = new Boolean(result);
}
return valid.booleanValue();
}
}
© 2015 - 2025 Weber Informatics LLC | Privacy Policy