Source: crypto/cipher/twofish.js

/* Modified by Recurity Labs GmbH 
 * 
 * Cipher.js
 * A block-cipher algorithm implementation on JavaScript
 * See Cipher.readme.txt for further information.
 *
 * Copyright(c) 2009 Atsushi Oka [ http://oka.nu/ ]
 * This script file is distributed under the LGPL
 *
 * ACKNOWLEDGMENT
 *
 *     The main subroutines are written by Michiel van Everdingen.
 * 
 *     Michiel van Everdingen
 *     http://home.versatel.nl/MAvanEverdingen/index.html
 * 
 *     All rights for these routines are reserved to Michiel van Everdingen.
 *
 */

/**
 * @module crypto/cipher/twofish
 */



////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//Math
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

var MAXINT = 0xFFFFFFFF;

function rotb(b, n) {
  return (b << n | b >>> (8 - n)) & 0xFF;
}

function rotw(w, n) {
  return (w << n | w >>> (32 - n)) & MAXINT;
}

function getW(a, i) {
  return a[i] | a[i + 1] << 8 | a[i + 2] << 16 | a[i + 3] << 24;
}

function setW(a, i, w) {
  a.splice(i, 4, w & 0xFF, (w >>> 8) & 0xFF, (w >>> 16) & 0xFF, (w >>> 24) & 0xFF);
}

function setWInv(a, i, w) {
  a.splice(i, 4, (w >>> 24) & 0xFF, (w >>> 16) & 0xFF, (w >>> 8) & 0xFF, w & 0xFF);
}

function getB(x, n) {
  return (x >>> (n * 8)) & 0xFF;
}

function getNrBits(i) {
  var n = 0;
  while (i > 0) {
    n++;
    i >>>= 1;
  }
  return n;
}

function getMask(n) {
  return (1 << n) - 1;
}

//added 2008/11/13 XXX MUST USE ONE-WAY HASH FUNCTION FOR SECURITY REASON

function randByte() {
  return Math.floor(Math.random() * 256);
}
// //////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// Twofish
// //////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

function createTwofish() {
  //
  var keyBytes = null;
  var dataBytes = null;
  var dataOffset = -1;
  // var dataLength = -1;
  var algorithmName = null;
  // var idx2 = -1;
  //

  algorithmName = "twofish";

  var tfsKey = [];
  var tfsM = [
    [],
    [],
    [],
    []
  ];

  function tfsInit(key) {
    keyBytes = key;
    var i, a, b, c, d, meKey = [],
      moKey = [],
      inKey = [];
    var kLen;
    var sKey = [];
    var f01, f5b, fef;

    var q0 = [
      [8, 1, 7, 13, 6, 15, 3, 2, 0, 11, 5, 9, 14, 12, 10, 4],
      [2, 8, 11, 13, 15, 7, 6, 14, 3, 1, 9, 4, 0, 10, 12, 5]
    ];
    var q1 = [
      [14, 12, 11, 8, 1, 2, 3, 5, 15, 4, 10, 6, 7, 0, 9, 13],
      [1, 14, 2, 11, 4, 12, 3, 7, 6, 13, 10, 5, 15, 9, 0, 8]
    ];
    var q2 = [
      [11, 10, 5, 14, 6, 13, 9, 0, 12, 8, 15, 3, 2, 4, 7, 1],
      [4, 12, 7, 5, 1, 6, 9, 10, 0, 14, 13, 8, 2, 11, 3, 15]
    ];
    var q3 = [
      [13, 7, 15, 4, 1, 2, 6, 14, 9, 11, 3, 0, 8, 5, 12, 10],
      [11, 9, 5, 1, 12, 3, 13, 14, 6, 4, 7, 15, 2, 0, 8, 10]
    ];
    var ror4 = [0, 8, 1, 9, 2, 10, 3, 11, 4, 12, 5, 13, 6, 14, 7, 15];
    var ashx = [0, 9, 2, 11, 4, 13, 6, 15, 8, 1, 10, 3, 12, 5, 14, 7];
    var q = [
      [],
      []
    ];
    var m = [
      [],
      [],
      [],
      []
    ];

    function ffm5b(x) {
      return x ^ (x >> 2) ^ [0, 90, 180, 238][x & 3];
    }

    function ffmEf(x) {
      return x ^ (x >> 1) ^ (x >> 2) ^ [0, 238, 180, 90][x & 3];
    }

    function mdsRem(p, q) {
      var i, t, u;
      for (i = 0; i < 8; i++) {
        t = q >>> 24;
        q = ((q << 8) & MAXINT) | p >>> 24;
        p = (p << 8) & MAXINT;
        u = t << 1;
        if (t & 128) {
          u ^= 333;
        }
        q ^= t ^ (u << 16);
        u ^= t >>> 1;
        if (t & 1) {
          u ^= 166;
        }
        q ^= u << 24 | u << 8;
      }
      return q;
    }

    function qp(n, x) {
      var a, b, c, d;
      a = x >> 4;
      b = x & 15;
      c = q0[n][a ^ b];
      d = q1[n][ror4[b] ^ ashx[a]];
      return q3[n][ror4[d] ^ ashx[c]] << 4 | q2[n][c ^ d];
    }

    function hFun(x, key) {
      var a = getB(x, 0),
        b = getB(x, 1),
        c = getB(x, 2),
        d = getB(x, 3);
      switch (kLen) {
        case 4:
          a = q[1][a] ^ getB(key[3], 0);
          b = q[0][b] ^ getB(key[3], 1);
          c = q[0][c] ^ getB(key[3], 2);
          d = q[1][d] ^ getB(key[3], 3);
        case 3:
          a = q[1][a] ^ getB(key[2], 0);
          b = q[1][b] ^ getB(key[2], 1);
          c = q[0][c] ^ getB(key[2], 2);
          d = q[0][d] ^ getB(key[2], 3);
        case 2:
          a = q[0][q[0][a] ^ getB(key[1], 0)] ^ getB(key[0], 0);
          b = q[0][q[1][b] ^ getB(key[1], 1)] ^ getB(key[0], 1);
          c = q[1][q[0][c] ^ getB(key[1], 2)] ^ getB(key[0], 2);
          d = q[1][q[1][d] ^ getB(key[1], 3)] ^ getB(key[0], 3);
      }
      return m[0][a] ^ m[1][b] ^ m[2][c] ^ m[3][d];
    }

    keyBytes = keyBytes.slice(0, 32);
    i = keyBytes.length;
    while (i != 16 && i != 24 && i != 32)
      keyBytes[i++] = 0;

    for (i = 0; i < keyBytes.length; i += 4) {
      inKey[i >> 2] = getW(keyBytes, i);
    }
    for (i = 0; i < 256; i++) {
      q[0][i] = qp(0, i);
      q[1][i] = qp(1, i);
    }
    for (i = 0; i < 256; i++) {
      f01 = q[1][i];
      f5b = ffm5b(f01);
      fef = ffmEf(f01);
      m[0][i] = f01 + (f5b << 8) + (fef << 16) + (fef << 24);
      m[2][i] = f5b + (fef << 8) + (f01 << 16) + (fef << 24);
      f01 = q[0][i];
      f5b = ffm5b(f01);
      fef = ffmEf(f01);
      m[1][i] = fef + (fef << 8) + (f5b << 16) + (f01 << 24);
      m[3][i] = f5b + (f01 << 8) + (fef << 16) + (f5b << 24);
    }

    kLen = inKey.length / 2;
    for (i = 0; i < kLen; i++) {
      a = inKey[i + i];
      meKey[i] = a;
      b = inKey[i + i + 1];
      moKey[i] = b;
      sKey[kLen - i - 1] = mdsRem(a, b);
    }
    for (i = 0; i < 40; i += 2) {
      a = 0x1010101 * i;
      b = a + 0x1010101;
      a = hFun(a, meKey);
      b = rotw(hFun(b, moKey), 8);
      tfsKey[i] = (a + b) & MAXINT;
      tfsKey[i + 1] = rotw(a + 2 * b, 9);
    }
    for (i = 0; i < 256; i++) {
      a = b = c = d = i;
      switch (kLen) {
        case 4:
          a = q[1][a] ^ getB(sKey[3], 0);
          b = q[0][b] ^ getB(sKey[3], 1);
          c = q[0][c] ^ getB(sKey[3], 2);
          d = q[1][d] ^ getB(sKey[3], 3);
        case 3:
          a = q[1][a] ^ getB(sKey[2], 0);
          b = q[1][b] ^ getB(sKey[2], 1);
          c = q[0][c] ^ getB(sKey[2], 2);
          d = q[0][d] ^ getB(sKey[2], 3);
        case 2:
          tfsM[0][i] = m[0][q[0][q[0][a] ^ getB(sKey[1], 0)] ^ getB(sKey[0], 0)];
          tfsM[1][i] = m[1][q[0][q[1][b] ^ getB(sKey[1], 1)] ^ getB(sKey[0], 1)];
          tfsM[2][i] = m[2][q[1][q[0][c] ^ getB(sKey[1], 2)] ^ getB(sKey[0], 2)];
          tfsM[3][i] = m[3][q[1][q[1][d] ^ getB(sKey[1], 3)] ^ getB(sKey[0], 3)];
      }
    }
  }

  function tfsG0(x) {
    return tfsM[0][getB(x, 0)] ^ tfsM[1][getB(x, 1)] ^ tfsM[2][getB(x, 2)] ^ tfsM[3][getB(x, 3)];
  }

  function tfsG1(x) {
    return tfsM[0][getB(x, 3)] ^ tfsM[1][getB(x, 0)] ^ tfsM[2][getB(x, 1)] ^ tfsM[3][getB(x, 2)];
  }

  function tfsFrnd(r, blk) {
    var a = tfsG0(blk[0]);
    var b = tfsG1(blk[1]);
    blk[2] = rotw(blk[2] ^ (a + b + tfsKey[4 * r + 8]) & MAXINT, 31);
    blk[3] = rotw(blk[3], 1) ^ (a + 2 * b + tfsKey[4 * r + 9]) & MAXINT;
    a = tfsG0(blk[2]);
    b = tfsG1(blk[3]);
    blk[0] = rotw(blk[0] ^ (a + b + tfsKey[4 * r + 10]) & MAXINT, 31);
    blk[1] = rotw(blk[1], 1) ^ (a + 2 * b + tfsKey[4 * r + 11]) & MAXINT;
  }

  function tfsIrnd(i, blk) {
    var a = tfsG0(blk[0]);
    var b = tfsG1(blk[1]);
    blk[2] = rotw(blk[2], 1) ^ (a + b + tfsKey[4 * i + 10]) & MAXINT;
    blk[3] = rotw(blk[3] ^ (a + 2 * b + tfsKey[4 * i + 11]) & MAXINT, 31);
    a = tfsG0(blk[2]);
    b = tfsG1(blk[3]);
    blk[0] = rotw(blk[0], 1) ^ (a + b + tfsKey[4 * i + 8]) & MAXINT;
    blk[1] = rotw(blk[1] ^ (a + 2 * b + tfsKey[4 * i + 9]) & MAXINT, 31);
  }

  function tfsClose() {
    tfsKey = [];
    tfsM = [
      [],
      [],
      [],
      []
    ];
  }

  function tfsEncrypt(data, offset) {
    dataBytes = data;
    dataOffset = offset;
    var blk = [getW(dataBytes, dataOffset) ^ tfsKey[0],
        getW(dataBytes, dataOffset + 4) ^ tfsKey[1],
        getW(dataBytes, dataOffset + 8) ^ tfsKey[2],
        getW(dataBytes, dataOffset + 12) ^ tfsKey[3]
    ];
    for (var j = 0; j < 8; j++) {
      tfsFrnd(j, blk);
    }
    setW(dataBytes, dataOffset, blk[2] ^ tfsKey[4]);
    setW(dataBytes, dataOffset + 4, blk[3] ^ tfsKey[5]);
    setW(dataBytes, dataOffset + 8, blk[0] ^ tfsKey[6]);
    setW(dataBytes, dataOffset + 12, blk[1] ^ tfsKey[7]);
    dataOffset += 16;
    return dataBytes;
  }

  function tfsDecrypt(data, offset) {
    dataBytes = data;
    dataOffset = offset;
    var blk = [getW(dataBytes, dataOffset) ^ tfsKey[4],
        getW(dataBytes, dataOffset + 4) ^ tfsKey[5],
        getW(dataBytes, dataOffset + 8) ^ tfsKey[6],
        getW(dataBytes, dataOffset + 12) ^ tfsKey[7]
    ];
    for (var j = 7; j >= 0; j--) {
      tfsIrnd(j, blk);
    }
    setW(dataBytes, dataOffset, blk[2] ^ tfsKey[0]);
    setW(dataBytes, dataOffset + 4, blk[3] ^ tfsKey[1]);
    setW(dataBytes, dataOffset + 8, blk[0] ^ tfsKey[2]);
    setW(dataBytes, dataOffset + 12, blk[1] ^ tfsKey[3]);
    dataOffset += 16;
  }

  // added by Recurity Labs

  function tfsFinal() {
    return dataBytes;
  }

  return {
    name: "twofish",
    blocksize: 128 / 8,
    open: tfsInit,
    close: tfsClose,
    encrypt: tfsEncrypt,
    decrypt: tfsDecrypt,
    // added by Recurity Labs
    finalize: tfsFinal
  };
}

var util = require('../../util.js');

// added by Recurity Labs

function TFencrypt(block, key) {
  var block_copy = [].concat(block);
  var tf = createTwofish();
  tf.open(util.str2bin(key), 0);
  var result = tf.encrypt(block_copy, 0);
  tf.close();
  return result;
}

function TF(key) {
  this.tf = createTwofish();
  this.tf.open(util.str2bin(key), 0);

  this.encrypt = function(block) {
    return this.tf.encrypt([].concat(block), 0);
  };
}


module.exports = TF;
module.exports.keySize = TF.prototype.keySize = 32;
module.exports.blockSize = TF.prototype.blockSize = 16;