package nth.api.cryptography.twofish; import nth.api.cryptography.twofish.galua.Galua256; /** * * @author Hau Trung Nguyen */ public class TwoFish { private static final byte[][] RS = new byte[][]{ new byte[]{(byte) 0x01, (byte) 0xA4, (byte) 0x55, (byte) 0x87, (byte) 0x5A, (byte) 0x58, (byte) 0xDB, (byte) 0x9E}, new byte[]{(byte) 0xA4, (byte) 0x56, (byte) 0x82, (byte) 0xF3, (byte) 0x1E, (byte) 0xC6, (byte) 0x68, (byte) 0xE5}, new byte[]{(byte) 0x02, (byte) 0xA1, (byte) 0xFC, (byte) 0xC1, (byte) 0x47, (byte) 0xAE, (byte) 0x3D, (byte) 0x19}, new byte[]{(byte) 0xA4, (byte) 0x55, (byte) 0x87, (byte) 0x5A, (byte) 0x58, (byte) 0xDB, (byte) 0x9E, (byte) 0x03} }; private static final byte[][] MDS = new byte[][]{ new byte[]{(byte) 0x01, (byte) 0xEF, (byte) 0x5B, (byte) 0x5B}, new byte[]{(byte) 0x5B, (byte) 0xEF, (byte) 0xEF, (byte) 0x01}, new byte[]{(byte) 0xEF, (byte) 0x5B, (byte) 0x01, (byte) 0xEF}, new byte[]{(byte) 0xEF, (byte) 0x01, (byte) 0xEF, (byte) 0x5B},}; private static final byte[] t00 = {0x8, 0x1, 0x7, 0xD, 0x6, 0xF, 0x3, 0x2, 0x0, 0xB, 0x5, 0x9, 0xE, 0xC, 0xA, 0x4}; private static final byte[] t01 = {0xE, 0xC, 0xB, 0x8, 0x1, 0x2, 0x3, 0x5, 0xF, 0x4, 0xA, 0x6, 0x7, 0x0, 0x9, 0xD}; private static final byte[] t02 = {0xB, 0xA, 0x5, 0xE, 0x6, 0xD, 0x9, 0x0, 0xC, 0x8, 0xF, 0x3, 0x2, 0x4, 0x7, 0x1}; private static final byte[] t03 = {0xD, 0x7, 0xF, 0x4, 0x1, 0x2, 0x6, 0xE, 0x9, 0xB, 0x3, 0x0, 0x8, 0x5, 0xC, 0xA}; // private static final byte[] t10 = {0x2, 0x8, 0xB, 0xD, 0xF, 0x7, 0x6, 0xE, 0x3, 0x1, 0x9, 0x4, 0x0, 0xA, 0xC, 0x5}; private static final byte[] t11 = {0x1, 0xE, 0x2, 0xB, 0x4, 0xC, 0x3, 0x7, 0x6, 0xD, 0xA, 0x5, 0xF, 0x9, 0x0, 0x8}; private static final byte[] t12 = {0x4, 0xC, 0x7, 0x5, 0x1, 0x6, 0x9, 0xA, 0x0, 0xE, 0xD, 0x8, 0x2, 0xB, 0x3, 0xF}; private static final byte[] t13 = {0xB, 0x9, 0x5, 0x1, 0xC, 0x3, 0xD, 0xE, 0x6, 0x4, 0x7, 0xF, 0x2, 0x0, 0x8, 0xA}; static int[] encrypt(int[] plainText, int[] key) { return encrypt(plainText, key, false); } static int[] encrypt(int[] plainText, int[] key, boolean debug) { final int[] roundKey01 = roundKeys(key, 0); final int[] roundKey23 = roundKeys(key, 1); final int[] roundKey45 = roundKeys(key, 2); final int[] roundKey67 = roundKeys(key, 3); // whitening int[] whitened = whitening(plainText, roundKey01[0], roundKey01[1], roundKey23[0], roundKey23[1]); // if (debug) { System.out.println("whitened:"); Utils.printInternal(whitened); } // for (int i = 0; i < 16; i++) { whitened = encryptionRound(whitened, key, i); if (debug) { System.out.println("R" + i + ":"); if (i % 2 == 0) { Utils.printInternal(whitened); } } whitened = new int[]{whitened[2], whitened[3], whitened[0], whitened[1]}; if (debug && i % 2 != 0) { Utils.printInternal(whitened); } } // Swapping whitened = new int[]{whitened[2], whitened[3], whitened[0], whitened[1]}; whitened = whitening(whitened, roundKey45[0], roundKey45[1], roundKey67[0], roundKey67[1]); return whitened; } public static int[] decrypt(int[] cypheredText, int[] key) { return decrypt(cypheredText, key, false); } public static int[] decrypt(int[] cypheredText, int[] key, boolean debug) { if (debug) { System.out.println("Cyphered text:"); Utils.printInput(cypheredText); } final int[] roundKey01 = roundKeys(key, 0); final int[] roundKey23 = roundKeys(key, 1); final int[] roundKey45 = roundKeys(key, 2); final int[] roundKey67 = roundKeys(key, 3); // whitening int[] whitened = whitening(cypheredText, roundKey45[0], roundKey45[1], roundKey67[0], roundKey67[1]); if (debug) { System.out.println("Whitened:"); Utils.printInternal(whitened); } // whitened = new int[]{whitened[2], whitened[3], whitened[0], whitened[1]}; for (int i = 15; i >= 0; i--) { whitened = decryptionRound(whitened, key, i); if (debug) { System.out.println("R" + (i + 1) + ":"); if (i % 2 == 0) { Utils.printInternal(whitened); } } whitened = new int[]{whitened[2], whitened[3], whitened[0], whitened[1]}; if (debug && i % 2 != 0) { Utils.printInternal(whitened); } } whitened = whitening(whitened, roundKey01[0], roundKey01[1], roundKey23[0], roundKey23[1]); if (debug) { System.out.println("Whitened:"); Utils.printInternal(whitened); } return whitened; } public static int[] whitening(int[] plainText, int k0, int k1, int k2, int k3) { return new int[]{ plainText[0] ^ k0, plainText[1] ^ k1, plainText[2] ^ k2, plainText[3] ^ k3 }; } public static int[] encryptionRound(int[] input, int[] key, int round) { final int[] s = getS(key); int t0 = h(input[0], s[1], s[0]); int t1 = h(Integer.rotateLeft(input[1], 8), s[1], s[0]); int[] pPht = pht(t0, t1); final int[] roundKeys2r_8_2r_9 = roundKeys(key, round + 4); // final int f0 = pPht[0] + roundKeys2r_8_2r_9[0]; final int f1 = pPht[1] + roundKeys2r_8_2r_9[1]; // int c2 = Integer.rotateRight((f0 ^ input[2]), 1); int c3 = (f1 ^ Integer.rotateLeft(input[3], 1)); // return new int[]{input[0], input[1], c2, c3}; } public static int[] decryptionRound(int[] input, int[] key, int round) { final int[] s = getS(key); int t0 = h(input[2], s[1], s[0]); int t1 = h(Integer.rotateLeft(input[3], 8), s[1], s[0]); final int[] pPht = pht(t0, t1); final int[] roundKeys = roundKeys(key, round + 4); // final int f0 = pPht[0] + roundKeys[0]; final int f1 = pPht[1] + roundKeys[1]; // final int p2 = Integer.rotateLeft(input[0], 1) ^ f0; final int p3 = Integer.rotateRight(input[1] ^ f1, 1); // return new int[]{p2, p3, input[2], input[3]}; } public static int[] pht(int a, int b) { int a1 = a + b; int b1 = (a + 2 * b); return new int[]{a1, b1}; } public static int h(int input, int l0, int l1) { Galua256 galua256 = new Galua256((byte) 0b01101001); final byte[] x = asBytes(input); final byte[] y = asBytes(l1); final byte[] z = asBytes(l0); final byte[] input11 = new byte[]{ q1((byte) (q0((byte) (q0(x[0]) ^ y[0])) ^ z[0])), q0((byte) (q0((byte) (q1(x[1]) ^ y[1])) ^ z[1])), q1((byte) (q1((byte) (q0(x[2]) ^ y[2])) ^ z[2])), q0((byte) (q1((byte) (q1(x[3]) ^ y[3])) ^ z[3])),}; return fromBytes(multiply(galua256, MDS, input11)); } public static byte q0(byte input) { byte a0 = (byte) ((input >> 4) & 0xF); byte b0 = (byte) (input & 0xF); byte a1 = (byte) (a0 ^ b0); byte b1 = (byte) (a0 ^ ((b0 & 1) << 3 | b0 >> 1) ^ ((8 * a0) & 0xF)); byte a2 = t00[a1]; byte b2 = t01[b1]; byte a3 = (byte) (a2 ^ b2); byte b3 = (byte) (a2 ^ ((b2 & 1) << 3 | b2 >> 1) ^ ((8 * a2) & 0xF)); byte a4 = t02[a3]; byte b4 = t03[b3]; return (byte) ((b4 << 4) | a4); } public static byte q1(byte input) { byte a0 = (byte) ((input >> 4) & 0xF); byte b0 = (byte) (input & 0xF); byte a1 = (byte) (a0 ^ b0); byte b1 = (byte) (a0 ^ ((b0 & 1) << 3 | b0 >> 1) ^ ((8 * a0) & 0xF)); byte a2 = t10[a1]; byte b2 = t11[b1]; byte a3 = (byte) (a2 ^ b2); byte b3 = (byte) (a2 ^ ((b2 & 1) << 3 | b2 >> 1) ^ ((8 * a2) & 0xF)); byte a4 = t12[a3]; byte b4 = t13[b3]; return (byte) ((b4 << 4) | a4); } public static int[] getS(int[] key) { final int m0 = key[0]; final int m1 = key[1]; final int m2 = key[2]; final int m3 = key[3]; final int S0 = RS(m0, m1); final int S1 = RS(m2, m3); return new int[]{S0, S1}; } private static int RS(int X, int Y) { byte[] x = asBytes(X); byte[] y = asBytes(Y); byte[] XY = new byte[8]; // Merging x and y System.arraycopy(x, 0, XY, 0, 4); System.arraycopy(y, 0, XY, 4, 4); // final byte[][] matrix = RS; Galua256 galua = new Galua256((byte) 0b01001101); // byte[] S = multiply(galua, matrix, XY); return fromBytes(S); } private static byte[] multiply(Galua256 galua, byte[][] matrix, byte[] vector) { byte[] S = new byte[vector.length]; for (int i = 0; i < matrix.length; i++) { final byte[] RSrow = matrix[i]; S[i] = galua.multiply(RSrow[0], vector[0]); for (int j = 1; j < RSrow.length; j++) { S[i] = galua.add(S[i], galua.multiply(RSrow[j], vector[j])); } } return S; } public static int[] roundKeys(int[] key, int round) { final int m0 = key[0]; final int m1 = key[1]; final int m2 = key[2]; final int m3 = key[3]; // final int[] Me = new int[]{m0, m2}; final int[] Mo = new int[]{m1, m3}; // final int rho = (1 << 24) | (1 << 16) | (1 << 8) | 1; final int Ai = h(2 * round * rho, Me[0], Me[1]); final int Bi = Integer.rotateLeft(h((2 * round + 1) * rho, Mo[0], Mo[1]), 8); final int[] pPht = pht(Ai, Bi); final int K2i = pPht[0]; final int K2i_1 = Integer.rotateLeft(pPht[1], 9); return new int[]{K2i, K2i_1}; } public static byte[] asBytes(int intValue) { return new byte[]{ (byte) (intValue), (byte) (intValue >>> 8), (byte) (intValue >>> 16), (byte) (intValue >>> 24),}; } public static int fromBytes(byte[] bytes) { int S0 = 0; for (int i = 0; i < 4; i++) { S0 |= ((0xFF & bytes[i]) << (i * 8)); } return S0; } }