/**
 * @file {@link http://asmjs.org Asm.js} implementation of the {@link https://en.wikipedia.org/wiki/Advanced_Encryption_Standard Advanced Encryption Standard}.
 * @author Artem S Vybornov <vybornov@gmail.com>
 * @license MIT
 */
export var AES_asm = function () {
  "use strict";

  /**
   * Galois Field stuff init flag
   */
  var ginit_done = false;

  /**
   * Galois Field exponentiation and logarithm tables for 3 (the generator)
   */
  var gexp3, glog3;

  /**
   * Init Galois Field tables
   */
  function ginit() {
    gexp3 = [],
      glog3 = [];

    var a = 1, c, d;
    for (c = 0; c < 255; c++) {
      gexp3[c] = a;

      // Multiply by three
      d = a & 0x80, a <<= 1, a &= 255;
      if (d === 0x80) a ^= 0x1b;
      a ^= gexp3[c];

      // Set the log table value
      glog3[gexp3[c]] = c;
    }
    gexp3[255] = gexp3[0];
    glog3[0] = 0;

    ginit_done = true;
  }

  /**
   * Galois Field multiplication
   * @param {number} a
   * @param {number} b
   * @return {number}
   */
  function gmul(a, b) {
    var c = gexp3[(glog3[a] + glog3[b]) % 255];
    if (a === 0 || b === 0) c = 0;
    return c;
  }

  /**
   * Galois Field reciprocal
   * @param {number} a
   * @return {number}
   */
  function ginv(a) {
    var i = gexp3[255 - glog3[a]];
    if (a === 0) i = 0;
    return i;
  }

  /**
   * AES stuff init flag
   */
  var aes_init_done = false;

  /**
   * Encryption, Decryption, S-Box and KeyTransform tables
   *
   * @type {number[]}
   */
  var aes_sbox;

  /**
   * @type {number[]}
   */
  var aes_sinv;

  /**
   * @type {number[][]}
   */
  var aes_enc;

  /**
   * @type {number[][]}
   */
  var aes_dec;

  /**
   * Init AES tables
   */
  function aes_init() {
    if (!ginit_done) ginit();

    // Calculates AES S-Box value
    function _s(a) {
      var c, s, x;
      s = x = ginv(a);
      for (c = 0; c < 4; c++) {
        s = ((s << 1) | (s >>> 7)) & 255;
        x ^= s;
      }
      x ^= 99;
      return x;
    }

    // Tables
    aes_sbox = [],
      aes_sinv = [],
      aes_enc = [[], [], [], []],
      aes_dec = [[], [], [], []];

    for (var i = 0; i < 256; i++) {
      var s = _s(i);

      // S-Box and its inverse
      aes_sbox[i] = s;
      aes_sinv[s] = i;

      // Ecryption and Decryption tables
      aes_enc[0][i] = (gmul(2, s) << 24) | (s << 16) | (s << 8) | gmul(3, s);
      aes_dec[0][s] = (gmul(14, i) << 24) | (gmul(9, i) << 16) | (gmul(13, i) << 8) | gmul(11, i);
      // Rotate tables
      for (var t = 1; t < 4; t++) {
        aes_enc[t][i] = (aes_enc[t - 1][i] >>> 8) | (aes_enc[t - 1][i] << 24);
        aes_dec[t][s] = (aes_dec[t - 1][s] >>> 8) | (aes_dec[t - 1][s] << 24);
      }
    }

    aes_init_done = true;
  }

  /**
   * Asm.js module constructor.
   *
   * <p>
   * Heap buffer layout by offset:
   * <pre>
   * 0x0000   encryption key schedule
   * 0x0400   decryption key schedule
   * 0x0800   sbox
   * 0x0c00   inv sbox
   * 0x1000   encryption tables
   * 0x2000   decryption tables
   * 0x3000   reserved (future GCM multiplication lookup table)
   * 0x4000   data
   * </pre>
   * Don't touch anything before <code>0x400</code>.
   * </p>
   *
   * @alias AES_asm
   * @class
   * @param foreign - <i>ignored</i>
   * @param buffer - heap buffer to link with
   */
  var wrapper = function (foreign, buffer) {
    // Init AES stuff for the first time
    if (!aes_init_done) aes_init();

    // Fill up AES tables
    var heap = new Uint32Array(buffer);
    heap.set(aes_sbox, 0x0800 >> 2);
    heap.set(aes_sinv, 0x0c00 >> 2);
    for (var i = 0; i < 4; i++) {
      heap.set(aes_enc[i], (0x1000 + 0x400 * i) >> 2);
      heap.set(aes_dec[i], (0x2000 + 0x400 * i) >> 2);
    }

    /**
     * Calculate AES key schedules.
     * @instance
     * @memberof AES_asm
     * @param {number} ks - key size, 4/6/8 (for 128/192/256-bit key correspondingly)
     * @param {number} k0 - key vector components
     * @param {number} k1 - key vector components
     * @param {number} k2 - key vector components
     * @param {number} k3 - key vector components
     * @param {number} k4 - key vector components
     * @param {number} k5 - key vector components
     * @param {number} k6 - key vector components
     * @param {number} k7 - key vector components
     */
    function set_key(ks, k0, k1, k2, k3, k4, k5, k6, k7) {
      var ekeys = heap.subarray(0x000, 60),
        dkeys = heap.subarray(0x100, 0x100 + 60);

      // Encryption key schedule
      ekeys.set([k0, k1, k2, k3, k4, k5, k6, k7]);
      for (var i = ks, rcon = 1; i < 4 * ks + 28; i++) {
        var k = ekeys[i - 1];
        if ((i % ks === 0) || (ks === 8 && i % ks === 4)) {
          k = aes_sbox[k >>> 24] << 24 ^ aes_sbox[k >>> 16 & 255] << 16 ^ aes_sbox[k >>> 8 & 255] << 8 ^ aes_sbox[k & 255];
        }
        if (i % ks === 0) {
          k = (k << 8) ^ (k >>> 24) ^ (rcon << 24);
          rcon = (rcon << 1) ^ ((rcon & 0x80) ? 0x1b : 0);
        }
        ekeys[i] = ekeys[i - ks] ^ k;
      }

      // Decryption key schedule
      for (var j = 0; j < i; j += 4) {
        for (var jj = 0; jj < 4; jj++) {
          var k = ekeys[i - (4 + j) + (4 - jj) % 4];
          if (j < 4 || j >= i - 4) {
            dkeys[j + jj] = k;
          } else {
            dkeys[j + jj] = aes_dec[0][aes_sbox[k >>> 24]]
              ^ aes_dec[1][aes_sbox[k >>> 16 & 255]]
              ^ aes_dec[2][aes_sbox[k >>> 8 & 255]]
              ^ aes_dec[3][aes_sbox[k & 255]];
          }
        }
      }

      // Set rounds number
      asm.set_rounds(ks + 5);
    }

    // create library object with necessary properties
    var stdlib = {Uint8Array: Uint8Array, Uint32Array: Uint32Array};

    var asm = function (stdlib, foreign, buffer) {
      "use asm";

      var S0 = 0, S1 = 0, S2 = 0, S3 = 0,
        I0 = 0, I1 = 0, I2 = 0, I3 = 0,
        N0 = 0, N1 = 0, N2 = 0, N3 = 0,
        M0 = 0, M1 = 0, M2 = 0, M3 = 0,
        H0 = 0, H1 = 0, H2 = 0, H3 = 0,
        R = 0;

      var HEAP = new stdlib.Uint32Array(buffer),
        DATA = new stdlib.Uint8Array(buffer);

      /**
       * AES core
       * @param {number} k - precomputed key schedule offset
       * @param {number} s - precomputed sbox table offset
       * @param {number} t - precomputed round table offset
       * @param {number} r - number of inner rounds to perform
       * @param {number} x0 - 128-bit input block vector
       * @param {number} x1 - 128-bit input block vector
       * @param {number} x2 - 128-bit input block vector
       * @param {number} x3 - 128-bit input block vector
       */
      function _core(k, s, t, r, x0, x1, x2, x3) {
        k = k | 0;
        s = s | 0;
        t = t | 0;
        r = r | 0;
        x0 = x0 | 0;
        x1 = x1 | 0;
        x2 = x2 | 0;
        x3 = x3 | 0;

        var t1 = 0, t2 = 0, t3 = 0,
          y0 = 0, y1 = 0, y2 = 0, y3 = 0,
          i = 0;

        t1 = t | 0x400, t2 = t | 0x800, t3 = t | 0xc00;

        // round 0
        x0 = x0 ^ HEAP[(k | 0) >> 2],
          x1 = x1 ^ HEAP[(k | 4) >> 2],
          x2 = x2 ^ HEAP[(k | 8) >> 2],
          x3 = x3 ^ HEAP[(k | 12) >> 2];

        // round 1..r
        for (i = 16; (i | 0) <= (r << 4); i = (i + 16) | 0) {
          y0 = HEAP[(t | x0 >> 22 & 1020) >> 2] ^ HEAP[(t1 | x1 >> 14 & 1020) >> 2] ^ HEAP[(t2 | x2 >> 6 & 1020) >> 2] ^ HEAP[(t3 | x3 << 2 & 1020) >> 2] ^ HEAP[(k | i | 0) >> 2],
            y1 = HEAP[(t | x1 >> 22 & 1020) >> 2] ^ HEAP[(t1 | x2 >> 14 & 1020) >> 2] ^ HEAP[(t2 | x3 >> 6 & 1020) >> 2] ^ HEAP[(t3 | x0 << 2 & 1020) >> 2] ^ HEAP[(k | i | 4) >> 2],
            y2 = HEAP[(t | x2 >> 22 & 1020) >> 2] ^ HEAP[(t1 | x3 >> 14 & 1020) >> 2] ^ HEAP[(t2 | x0 >> 6 & 1020) >> 2] ^ HEAP[(t3 | x1 << 2 & 1020) >> 2] ^ HEAP[(k | i | 8) >> 2],
            y3 = HEAP[(t | x3 >> 22 & 1020) >> 2] ^ HEAP[(t1 | x0 >> 14 & 1020) >> 2] ^ HEAP[(t2 | x1 >> 6 & 1020) >> 2] ^ HEAP[(t3 | x2 << 2 & 1020) >> 2] ^ HEAP[(k | i | 12) >> 2];
          x0 = y0, x1 = y1, x2 = y2, x3 = y3;
        }

        // final round
        S0 = HEAP[(s | x0 >> 22 & 1020) >> 2] << 24 ^ HEAP[(s | x1 >> 14 & 1020) >> 2] << 16 ^ HEAP[(s | x2 >> 6 & 1020) >> 2] << 8 ^ HEAP[(s | x3 << 2 & 1020) >> 2] ^ HEAP[(k | i | 0) >> 2],
          S1 = HEAP[(s | x1 >> 22 & 1020) >> 2] << 24 ^ HEAP[(s | x2 >> 14 & 1020) >> 2] << 16 ^ HEAP[(s | x3 >> 6 & 1020) >> 2] << 8 ^ HEAP[(s | x0 << 2 & 1020) >> 2] ^ HEAP[(k | i | 4) >> 2],
          S2 = HEAP[(s | x2 >> 22 & 1020) >> 2] << 24 ^ HEAP[(s | x3 >> 14 & 1020) >> 2] << 16 ^ HEAP[(s | x0 >> 6 & 1020) >> 2] << 8 ^ HEAP[(s | x1 << 2 & 1020) >> 2] ^ HEAP[(k | i | 8) >> 2],
          S3 = HEAP[(s | x3 >> 22 & 1020) >> 2] << 24 ^ HEAP[(s | x0 >> 14 & 1020) >> 2] << 16 ^ HEAP[(s | x1 >> 6 & 1020) >> 2] << 8 ^ HEAP[(s | x2 << 2 & 1020) >> 2] ^ HEAP[(k | i | 12) >> 2];
      }

      /**
       * ECB mode encryption
       * @param {number} x0 - 128-bit input block vector
       * @param {number} x1 - 128-bit input block vector
       * @param {number} x2 - 128-bit input block vector
       * @param {number} x3 - 128-bit input block vector
       */
      function _ecb_enc(x0, x1, x2, x3) {
        x0 = x0 | 0;
        x1 = x1 | 0;
        x2 = x2 | 0;
        x3 = x3 | 0;

        _core(
          0x0000, 0x0800, 0x1000,
          R,
          x0,
          x1,
          x2,
          x3
        );
      }

      /**
       * ECB mode decryption
       * @param {number} x0 - 128-bit input block vector
       * @param {number} x1 - 128-bit input block vector
       * @param {number} x2 - 128-bit input block vector
       * @param {number} x3 - 128-bit input block vector
       */
      function _ecb_dec(x0, x1, x2, x3) {
        x0 = x0 | 0;
        x1 = x1 | 0;
        x2 = x2 | 0;
        x3 = x3 | 0;

        var t = 0;

        _core(
          0x0400, 0x0c00, 0x2000,
          R,
          x0,
          x3,
          x2,
          x1
        );

        t = S1, S1 = S3, S3 = t;
      }


      /**
       * CBC mode encryption
       * @param {number} x0 - 128-bit input block vector
       * @param {number} x1 - 128-bit input block vector
       * @param {number} x2 - 128-bit input block vector
       * @param {number} x3 - 128-bit input block vector
       */
      function _cbc_enc(x0, x1, x2, x3) {
        x0 = x0 | 0;
        x1 = x1 | 0;
        x2 = x2 | 0;
        x3 = x3 | 0;

        _core(
          0x0000, 0x0800, 0x1000,
          R,
          I0 ^ x0,
          I1 ^ x1,
          I2 ^ x2,
          I3 ^ x3
        );

        I0 = S0,
          I1 = S1,
          I2 = S2,
          I3 = S3;
      }

      /**
       * CBC mode decryption
       * @param {number} x0 - 128-bit input block vector
       * @param {number} x1 - 128-bit input block vector
       * @param {number} x2 - 128-bit input block vector
       * @param {number} x3 - 128-bit input block vector
       */
      function _cbc_dec(x0, x1, x2, x3) {
        x0 = x0 | 0;
        x1 = x1 | 0;
        x2 = x2 | 0;
        x3 = x3 | 0;

        var t = 0;

        _core(
          0x0400, 0x0c00, 0x2000,
          R,
          x0,
          x3,
          x2,
          x1
        );

        t = S1, S1 = S3, S3 = t;

        S0 = S0 ^ I0,
          S1 = S1 ^ I1,
          S2 = S2 ^ I2,
          S3 = S3 ^ I3;

        I0 = x0,
          I1 = x1,
          I2 = x2,
          I3 = x3;
      }

      /**
       * CFB mode encryption
       * @param {number} x0 - 128-bit input block vector
       * @param {number} x1 - 128-bit input block vector
       * @param {number} x2 - 128-bit input block vector
       * @param {number} x3 - 128-bit input block vector
       */
      function _cfb_enc(x0, x1, x2, x3) {
        x0 = x0 | 0;
        x1 = x1 | 0;
        x2 = x2 | 0;
        x3 = x3 | 0;

        _core(
          0x0000, 0x0800, 0x1000,
          R,
          I0,
          I1,
          I2,
          I3
        );

        I0 = S0 = S0 ^ x0,
          I1 = S1 = S1 ^ x1,
          I2 = S2 = S2 ^ x2,
          I3 = S3 = S3 ^ x3;
      }


      /**
       * CFB mode decryption
       * @param {number} x0 - 128-bit input block vector
       * @param {number} x1 - 128-bit input block vector
       * @param {number} x2 - 128-bit input block vector
       * @param {number} x3 - 128-bit input block vector
       */
      function _cfb_dec(x0, x1, x2, x3) {
        x0 = x0 | 0;
        x1 = x1 | 0;
        x2 = x2 | 0;
        x3 = x3 | 0;

        _core(
          0x0000, 0x0800, 0x1000,
          R,
          I0,
          I1,
          I2,
          I3
        );

        S0 = S0 ^ x0,
          S1 = S1 ^ x1,
          S2 = S2 ^ x2,
          S3 = S3 ^ x3;

        I0 = x0,
          I1 = x1,
          I2 = x2,
          I3 = x3;
      }

      /**
       * OFB mode encryption / decryption
       * @param {number} x0 - 128-bit input block vector
       * @param {number} x1 - 128-bit input block vector
       * @param {number} x2 - 128-bit input block vector
       * @param {number} x3 - 128-bit input block vector
       */
      function _ofb(x0, x1, x2, x3) {
        x0 = x0 | 0;
        x1 = x1 | 0;
        x2 = x2 | 0;
        x3 = x3 | 0;

        _core(
          0x0000, 0x0800, 0x1000,
          R,
          I0,
          I1,
          I2,
          I3
        );

        I0 = S0,
          I1 = S1,
          I2 = S2,
          I3 = S3;

        S0 = S0 ^ x0,
          S1 = S1 ^ x1,
          S2 = S2 ^ x2,
          S3 = S3 ^ x3;
      }

      /**
       * CTR mode encryption / decryption
       * @param {number} x0 - 128-bit input block vector
       * @param {number} x1 - 128-bit input block vector
       * @param {number} x2 - 128-bit input block vector
       * @param {number} x3 - 128-bit input block vector
       */
      function _ctr(x0, x1, x2, x3) {
        x0 = x0 | 0;
        x1 = x1 | 0;
        x2 = x2 | 0;
        x3 = x3 | 0;

        _core(
          0x0000, 0x0800, 0x1000,
          R,
          N0,
          N1,
          N2,
          N3
        );

        N3 = (~M3 & N3) | M3 & (N3 + 1);
          N2 = (~M2 & N2) | M2 & (N2 + ((N3 | 0) == 0));
          N1 = (~M1 & N1) | M1 & (N1 + ((N2 | 0) == 0));
          N0 = (~M0 & N0) | M0 & (N0 + ((N1 | 0) == 0));

        S0 = S0 ^ x0;
          S1 = S1 ^ x1;
          S2 = S2 ^ x2;
          S3 = S3 ^ x3;
      }

      /**
       * GCM mode MAC calculation
       * @param {number} x0 - 128-bit input block vector
       * @param {number} x1 - 128-bit input block vector
       * @param {number} x2 - 128-bit input block vector
       * @param {number} x3 - 128-bit input block vector
       */
      function _gcm_mac(x0, x1, x2, x3) {
        x0 = x0 | 0;
        x1 = x1 | 0;
        x2 = x2 | 0;
        x3 = x3 | 0;

        var y0 = 0, y1 = 0, y2 = 0, y3 = 0,
          z0 = 0, z1 = 0, z2 = 0, z3 = 0,
          i = 0, c = 0;

        x0 = x0 ^ I0,
          x1 = x1 ^ I1,
          x2 = x2 ^ I2,
          x3 = x3 ^ I3;

        y0 = H0 | 0,
          y1 = H1 | 0,
          y2 = H2 | 0,
          y3 = H3 | 0;

        for (; (i | 0) < 128; i = (i + 1) | 0) {
          if (y0 >>> 31) {
            z0 = z0 ^ x0,
              z1 = z1 ^ x1,
              z2 = z2 ^ x2,
              z3 = z3 ^ x3;
          }

          y0 = (y0 << 1) | (y1 >>> 31),
            y1 = (y1 << 1) | (y2 >>> 31),
            y2 = (y2 << 1) | (y3 >>> 31),
            y3 = (y3 << 1);

          c = x3 & 1;

          x3 = (x3 >>> 1) | (x2 << 31),
            x2 = (x2 >>> 1) | (x1 << 31),
            x1 = (x1 >>> 1) | (x0 << 31),
            x0 = (x0 >>> 1);

          if (c) x0 = x0 ^ 0xe1000000;
        }

        I0 = z0,
          I1 = z1,
          I2 = z2,
          I3 = z3;
      }

      /**
       * Set the internal rounds number.
       * @instance
       * @memberof AES_asm
       * @param {number} r - number if inner AES rounds
       */
      function set_rounds(r) {
        r = r | 0;
        R = r;
      }

      /**
       * Populate the internal state of the module.
       * @instance
       * @memberof AES_asm
       * @param {number} s0 - state vector
       * @param {number} s1 - state vector
       * @param {number} s2 - state vector
       * @param {number} s3 - state vector
       */
      function set_state(s0, s1, s2, s3) {
        s0 = s0 | 0;
        s1 = s1 | 0;
        s2 = s2 | 0;
        s3 = s3 | 0;

        S0 = s0,
          S1 = s1,
          S2 = s2,
          S3 = s3;
      }

      /**
       * Populate the internal iv of the module.
       * @instance
       * @memberof AES_asm
       * @param {number} i0 - iv vector
       * @param {number} i1 - iv vector
       * @param {number} i2 - iv vector
       * @param {number} i3 - iv vector
       */
      function set_iv(i0, i1, i2, i3) {
        i0 = i0 | 0;
        i1 = i1 | 0;
        i2 = i2 | 0;
        i3 = i3 | 0;

        I0 = i0,
          I1 = i1,
          I2 = i2,
          I3 = i3;
      }

      /**
       * Set nonce for CTR-family modes.
       * @instance
       * @memberof AES_asm
       * @param {number} n0 - nonce vector
       * @param {number} n1 - nonce vector
       * @param {number} n2 - nonce vector
       * @param {number} n3 - nonce vector
       */
      function set_nonce(n0, n1, n2, n3) {
        n0 = n0 | 0;
        n1 = n1 | 0;
        n2 = n2 | 0;
        n3 = n3 | 0;

        N0 = n0,
          N1 = n1,
          N2 = n2,
          N3 = n3;
      }

      /**
       * Set counter mask for CTR-family modes.
       * @instance
       * @memberof AES_asm
       * @param {number} m0 - counter mask vector
       * @param {number} m1 - counter mask vector
       * @param {number} m2 - counter mask vector
       * @param {number} m3 - counter mask vector
       */
      function set_mask(m0, m1, m2, m3) {
        m0 = m0 | 0;
        m1 = m1 | 0;
        m2 = m2 | 0;
        m3 = m3 | 0;

        M0 = m0,
          M1 = m1,
          M2 = m2,
          M3 = m3;
      }

      /**
       * Set counter for CTR-family modes.
       * @instance
       * @memberof AES_asm
       * @param {number} c0 - counter vector
       * @param {number} c1 - counter vector
       * @param {number} c2 - counter vector
       * @param {number} c3 - counter vector
       */
      function set_counter(c0, c1, c2, c3) {
        c0 = c0 | 0;
        c1 = c1 | 0;
        c2 = c2 | 0;
        c3 = c3 | 0;

        N3 = (~M3 & N3) | M3 & c3,
          N2 = (~M2 & N2) | M2 & c2,
          N1 = (~M1 & N1) | M1 & c1,
          N0 = (~M0 & N0) | M0 & c0;
      }

      /**
       * Store the internal state vector into the heap.
       * @instance
       * @memberof AES_asm
       * @param {number} pos - offset where to put the data
       * @return {number} The number of bytes have been written into the heap, always 16.
       */
      function get_state(pos) {
        pos = pos | 0;

        if (pos & 15) return -1;

        DATA[pos | 0] = S0 >>> 24,
          DATA[pos | 1] = S0 >>> 16 & 255,
          DATA[pos | 2] = S0 >>> 8 & 255,
          DATA[pos | 3] = S0 & 255,
          DATA[pos | 4] = S1 >>> 24,
          DATA[pos | 5] = S1 >>> 16 & 255,
          DATA[pos | 6] = S1 >>> 8 & 255,
          DATA[pos | 7] = S1 & 255,
          DATA[pos | 8] = S2 >>> 24,
          DATA[pos | 9] = S2 >>> 16 & 255,
          DATA[pos | 10] = S2 >>> 8 & 255,
          DATA[pos | 11] = S2 & 255,
          DATA[pos | 12] = S3 >>> 24,
          DATA[pos | 13] = S3 >>> 16 & 255,
          DATA[pos | 14] = S3 >>> 8 & 255,
          DATA[pos | 15] = S3 & 255;

        return 16;
      }

      /**
       * Store the internal iv vector into the heap.
       * @instance
       * @memberof AES_asm
       * @param {number} pos - offset where to put the data
       * @return {number} The number of bytes have been written into the heap, always 16.
       */
      function get_iv(pos) {
        pos = pos | 0;

        if (pos & 15) return -1;

        DATA[pos | 0] = I0 >>> 24,
          DATA[pos | 1] = I0 >>> 16 & 255,
          DATA[pos | 2] = I0 >>> 8 & 255,
          DATA[pos | 3] = I0 & 255,
          DATA[pos | 4] = I1 >>> 24,
          DATA[pos | 5] = I1 >>> 16 & 255,
          DATA[pos | 6] = I1 >>> 8 & 255,
          DATA[pos | 7] = I1 & 255,
          DATA[pos | 8] = I2 >>> 24,
          DATA[pos | 9] = I2 >>> 16 & 255,
          DATA[pos | 10] = I2 >>> 8 & 255,
          DATA[pos | 11] = I2 & 255,
          DATA[pos | 12] = I3 >>> 24,
          DATA[pos | 13] = I3 >>> 16 & 255,
          DATA[pos | 14] = I3 >>> 8 & 255,
          DATA[pos | 15] = I3 & 255;

        return 16;
      }

      /**
       * GCM initialization.
       * @instance
       * @memberof AES_asm
       */
      function gcm_init() {
        _ecb_enc(0, 0, 0, 0);
        H0 = S0,
          H1 = S1,
          H2 = S2,
          H3 = S3;
      }

      /**
       * Perform ciphering operation on the supplied data.
       * @instance
       * @memberof AES_asm
       * @param {number} mode - block cipher mode (see {@link AES_asm} mode constants)
       * @param {number} pos - offset of the data being processed
       * @param {number} len - length of the data being processed
       * @return {number} Actual amount of data have been processed.
       */
      function cipher(mode, pos, len) {
        mode = mode | 0;
        pos = pos | 0;
        len = len | 0;

        var ret = 0;

        if (pos & 15) return -1;

        while ((len | 0) >= 16) {
          _cipher_modes[mode & 7](
            DATA[pos | 0] << 24 | DATA[pos | 1] << 16 | DATA[pos | 2] << 8 | DATA[pos | 3],
            DATA[pos | 4] << 24 | DATA[pos | 5] << 16 | DATA[pos | 6] << 8 | DATA[pos | 7],
            DATA[pos | 8] << 24 | DATA[pos | 9] << 16 | DATA[pos | 10] << 8 | DATA[pos | 11],
            DATA[pos | 12] << 24 | DATA[pos | 13] << 16 | DATA[pos | 14] << 8 | DATA[pos | 15]
          );

          DATA[pos | 0] = S0 >>> 24,
            DATA[pos | 1] = S0 >>> 16 & 255,
            DATA[pos | 2] = S0 >>> 8 & 255,
            DATA[pos | 3] = S0 & 255,
            DATA[pos | 4] = S1 >>> 24,
            DATA[pos | 5] = S1 >>> 16 & 255,
            DATA[pos | 6] = S1 >>> 8 & 255,
            DATA[pos | 7] = S1 & 255,
            DATA[pos | 8] = S2 >>> 24,
            DATA[pos | 9] = S2 >>> 16 & 255,
            DATA[pos | 10] = S2 >>> 8 & 255,
            DATA[pos | 11] = S2 & 255,
            DATA[pos | 12] = S3 >>> 24,
            DATA[pos | 13] = S3 >>> 16 & 255,
            DATA[pos | 14] = S3 >>> 8 & 255,
            DATA[pos | 15] = S3 & 255;

          ret = (ret + 16) | 0,
            pos = (pos + 16) | 0,
            len = (len - 16) | 0;
        }

        return ret | 0;
      }

      /**
       * Calculates MAC of the supplied data.
       * @instance
       * @memberof AES_asm
       * @param {number} mode - block cipher mode (see {@link AES_asm} mode constants)
       * @param {number} pos - offset of the data being processed
       * @param {number} len - length of the data being processed
       * @return {number} Actual amount of data have been processed.
       */
      function mac(mode, pos, len) {
        mode = mode | 0;
        pos = pos | 0;
        len = len | 0;

        var ret = 0;

        if (pos & 15) return -1;

        while ((len | 0) >= 16) {
          _mac_modes[mode & 1](
            DATA[pos | 0] << 24 | DATA[pos | 1] << 16 | DATA[pos | 2] << 8 | DATA[pos | 3],
            DATA[pos | 4] << 24 | DATA[pos | 5] << 16 | DATA[pos | 6] << 8 | DATA[pos | 7],
            DATA[pos | 8] << 24 | DATA[pos | 9] << 16 | DATA[pos | 10] << 8 | DATA[pos | 11],
            DATA[pos | 12] << 24 | DATA[pos | 13] << 16 | DATA[pos | 14] << 8 | DATA[pos | 15]
          );

          ret = (ret + 16) | 0,
            pos = (pos + 16) | 0,
            len = (len - 16) | 0;
        }

        return ret | 0;
      }

      /**
       * AES cipher modes table (virual methods)
       */
      var _cipher_modes = [_ecb_enc, _ecb_dec, _cbc_enc, _cbc_dec, _cfb_enc, _cfb_dec, _ofb, _ctr];

      /**
       * AES MAC modes table (virual methods)
       */
      var _mac_modes = [_cbc_enc, _gcm_mac];

      /**
       * Asm.js module exports
       */
      return {
        set_rounds: set_rounds,
        set_state: set_state,
        set_iv: set_iv,
        set_nonce: set_nonce,
        set_mask: set_mask,
        set_counter: set_counter,
        get_state: get_state,
        get_iv: get_iv,
        gcm_init: gcm_init,
        cipher: cipher,
        mac: mac,
      };
    }(stdlib, foreign, buffer);

    asm.set_key = set_key;

    return asm;
  };

  /**
   * AES enciphering mode constants
   * @enum {number}
   * @const
   */
  wrapper.ENC = {
    ECB: 0,
    CBC: 2,
    CFB: 4,
    OFB: 6,
    CTR: 7,
  },

    /**
     * AES deciphering mode constants
     * @enum {number}
     * @const
     */
    wrapper.DEC = {
      ECB: 1,
      CBC: 3,
      CFB: 5,
      OFB: 6,
      CTR: 7,
    },

    /**
     * AES MAC mode constants
     * @enum {number}
     * @const
     */
    wrapper.MAC = {
      CBC: 0,
      GCM: 1,
    };

  /**
   * Heap data offset
   * @type {number}
   * @const
   */
  wrapper.HEAP_DATA = 0x4000;

  return wrapper;
}();