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node_modules/browserify-aes/aes.js 6.1 KB
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  // based on the aes implimentation in triple sec
  // https://github.com/keybase/triplesec
  // which is in turn based on the one from crypto-js
  // https://code.google.com/p/crypto-js/
  
  var Buffer = require('safe-buffer').Buffer
  
  function asUInt32Array (buf) {
    if (!Buffer.isBuffer(buf)) buf = Buffer.from(buf)
  
    var len = (buf.length / 4) | 0
    var out = new Array(len)
  
    for (var i = 0; i < len; i++) {
      out[i] = buf.readUInt32BE(i * 4)
    }
  
    return out
  }
  
  function scrubVec (v) {
    for (var i = 0; i < v.length; v++) {
      v[i] = 0
    }
  }
  
  function cryptBlock (M, keySchedule, SUB_MIX, SBOX, nRounds) {
    var SUB_MIX0 = SUB_MIX[0]
    var SUB_MIX1 = SUB_MIX[1]
    var SUB_MIX2 = SUB_MIX[2]
    var SUB_MIX3 = SUB_MIX[3]
  
    var s0 = M[0] ^ keySchedule[0]
    var s1 = M[1] ^ keySchedule[1]
    var s2 = M[2] ^ keySchedule[2]
    var s3 = M[3] ^ keySchedule[3]
    var t0, t1, t2, t3
    var ksRow = 4
  
    for (var round = 1; round < nRounds; round++) {
      t0 = SUB_MIX0[s0 >>> 24] ^ SUB_MIX1[(s1 >>> 16) & 0xff] ^ SUB_MIX2[(s2 >>> 8) & 0xff] ^ SUB_MIX3[s3 & 0xff] ^ keySchedule[ksRow++]
      t1 = SUB_MIX0[s1 >>> 24] ^ SUB_MIX1[(s2 >>> 16) & 0xff] ^ SUB_MIX2[(s3 >>> 8) & 0xff] ^ SUB_MIX3[s0 & 0xff] ^ keySchedule[ksRow++]
      t2 = SUB_MIX0[s2 >>> 24] ^ SUB_MIX1[(s3 >>> 16) & 0xff] ^ SUB_MIX2[(s0 >>> 8) & 0xff] ^ SUB_MIX3[s1 & 0xff] ^ keySchedule[ksRow++]
      t3 = SUB_MIX0[s3 >>> 24] ^ SUB_MIX1[(s0 >>> 16) & 0xff] ^ SUB_MIX2[(s1 >>> 8) & 0xff] ^ SUB_MIX3[s2 & 0xff] ^ keySchedule[ksRow++]
      s0 = t0
      s1 = t1
      s2 = t2
      s3 = t3
    }
  
    t0 = ((SBOX[s0 >>> 24] << 24) | (SBOX[(s1 >>> 16) & 0xff] << 16) | (SBOX[(s2 >>> 8) & 0xff] << 8) | SBOX[s3 & 0xff]) ^ keySchedule[ksRow++]
    t1 = ((SBOX[s1 >>> 24] << 24) | (SBOX[(s2 >>> 16) & 0xff] << 16) | (SBOX[(s3 >>> 8) & 0xff] << 8) | SBOX[s0 & 0xff]) ^ keySchedule[ksRow++]
    t2 = ((SBOX[s2 >>> 24] << 24) | (SBOX[(s3 >>> 16) & 0xff] << 16) | (SBOX[(s0 >>> 8) & 0xff] << 8) | SBOX[s1 & 0xff]) ^ keySchedule[ksRow++]
    t3 = ((SBOX[s3 >>> 24] << 24) | (SBOX[(s0 >>> 16) & 0xff] << 16) | (SBOX[(s1 >>> 8) & 0xff] << 8) | SBOX[s2 & 0xff]) ^ keySchedule[ksRow++]
    t0 = t0 >>> 0
    t1 = t1 >>> 0
    t2 = t2 >>> 0
    t3 = t3 >>> 0
  
    return [t0, t1, t2, t3]
  }
  
  // AES constants
  var RCON = [0x00, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36]
  var G = (function () {
    // Compute double table
    var d = new Array(256)
    for (var j = 0; j < 256; j++) {
      if (j < 128) {
        d[j] = j << 1
      } else {
        d[j] = (j << 1) ^ 0x11b
      }
    }
  
    var SBOX = []
    var INV_SBOX = []
    var SUB_MIX = [[], [], [], []]
    var INV_SUB_MIX = [[], [], [], []]
  
    // Walk GF(2^8)
    var x = 0
    var xi = 0
    for (var i = 0; i < 256; ++i) {
      // Compute sbox
      var sx = xi ^ (xi << 1) ^ (xi << 2) ^ (xi << 3) ^ (xi << 4)
      sx = (sx >>> 8) ^ (sx & 0xff) ^ 0x63
      SBOX[x] = sx
      INV_SBOX[sx] = x
  
      // Compute multiplication
      var x2 = d[x]
      var x4 = d[x2]
      var x8 = d[x4]
  
      // Compute sub bytes, mix columns tables
      var t = (d[sx] * 0x101) ^ (sx * 0x1010100)
      SUB_MIX[0][x] = (t << 24) | (t >>> 8)
      SUB_MIX[1][x] = (t << 16) | (t >>> 16)
      SUB_MIX[2][x] = (t << 8) | (t >>> 24)
      SUB_MIX[3][x] = t
  
      // Compute inv sub bytes, inv mix columns tables
      t = (x8 * 0x1010101) ^ (x4 * 0x10001) ^ (x2 * 0x101) ^ (x * 0x1010100)
      INV_SUB_MIX[0][sx] = (t << 24) | (t >>> 8)
      INV_SUB_MIX[1][sx] = (t << 16) | (t >>> 16)
      INV_SUB_MIX[2][sx] = (t << 8) | (t >>> 24)
      INV_SUB_MIX[3][sx] = t
  
      if (x === 0) {
        x = xi = 1
      } else {
        x = x2 ^ d[d[d[x8 ^ x2]]]
        xi ^= d[d[xi]]
      }
    }
  
    return {
      SBOX: SBOX,
      INV_SBOX: INV_SBOX,
      SUB_MIX: SUB_MIX,
      INV_SUB_MIX: INV_SUB_MIX
    }
  })()
  
  function AES (key) {
    this._key = asUInt32Array(key)
    this._reset()
  }
  
  AES.blockSize = 4 * 4
  AES.keySize = 256 / 8
  AES.prototype.blockSize = AES.blockSize
  AES.prototype.keySize = AES.keySize
  AES.prototype._reset = function () {
    var keyWords = this._key
    var keySize = keyWords.length
    var nRounds = keySize + 6
    var ksRows = (nRounds + 1) * 4
  
    var keySchedule = []
    for (var k = 0; k < keySize; k++) {
      keySchedule[k] = keyWords[k]
    }
  
    for (k = keySize; k < ksRows; k++) {
      var t = keySchedule[k - 1]
  
      if (k % keySize === 0) {
        t = (t << 8) | (t >>> 24)
        t =
          (G.SBOX[t >>> 24] << 24) |
          (G.SBOX[(t >>> 16) & 0xff] << 16) |
          (G.SBOX[(t >>> 8) & 0xff] << 8) |
          (G.SBOX[t & 0xff])
  
        t ^= RCON[(k / keySize) | 0] << 24
      } else if (keySize > 6 && k % keySize === 4) {
        t =
          (G.SBOX[t >>> 24] << 24) |
          (G.SBOX[(t >>> 16) & 0xff] << 16) |
          (G.SBOX[(t >>> 8) & 0xff] << 8) |
          (G.SBOX[t & 0xff])
      }
  
      keySchedule[k] = keySchedule[k - keySize] ^ t
    }
  
    var invKeySchedule = []
    for (var ik = 0; ik < ksRows; ik++) {
      var ksR = ksRows - ik
      var tt = keySchedule[ksR - (ik % 4 ? 0 : 4)]
  
      if (ik < 4 || ksR <= 4) {
        invKeySchedule[ik] = tt
      } else {
        invKeySchedule[ik] =
          G.INV_SUB_MIX[0][G.SBOX[tt >>> 24]] ^
          G.INV_SUB_MIX[1][G.SBOX[(tt >>> 16) & 0xff]] ^
          G.INV_SUB_MIX[2][G.SBOX[(tt >>> 8) & 0xff]] ^
          G.INV_SUB_MIX[3][G.SBOX[tt & 0xff]]
      }
    }
  
    this._nRounds = nRounds
    this._keySchedule = keySchedule
    this._invKeySchedule = invKeySchedule
  }
  
  AES.prototype.encryptBlockRaw = function (M) {
    M = asUInt32Array(M)
    return cryptBlock(M, this._keySchedule, G.SUB_MIX, G.SBOX, this._nRounds)
  }
  
  AES.prototype.encryptBlock = function (M) {
    var out = this.encryptBlockRaw(M)
    var buf = Buffer.allocUnsafe(16)
    buf.writeUInt32BE(out[0], 0)
    buf.writeUInt32BE(out[1], 4)
    buf.writeUInt32BE(out[2], 8)
    buf.writeUInt32BE(out[3], 12)
    return buf
  }
  
  AES.prototype.decryptBlock = function (M) {
    M = asUInt32Array(M)
  
    // swap
    var m1 = M[1]
    M[1] = M[3]
    M[3] = m1
  
    var out = cryptBlock(M, this._invKeySchedule, G.INV_SUB_MIX, G.INV_SBOX, this._nRounds)
    var buf = Buffer.allocUnsafe(16)
    buf.writeUInt32BE(out[0], 0)
    buf.writeUInt32BE(out[3], 4)
    buf.writeUInt32BE(out[2], 8)
    buf.writeUInt32BE(out[1], 12)
    return buf
  }
  
  AES.prototype.scrub = function () {
    scrubVec(this._keySchedule)
    scrubVec(this._invKeySchedule)
    scrubVec(this._key)
  }
  
  module.exports.AES = AES