yanchengPowerSupply/node_modules/aes-decrypter/es5/aes.js

245 lines
8.5 KiB
JavaScript

/**
* @file aes.js
*
* This file contains an adaptation of the AES decryption algorithm
* from the Standford Javascript Cryptography Library. That work is
* covered by the following copyright and permissions notice:
*
* Copyright 2009-2010 Emily Stark, Mike Hamburg, Dan Boneh.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
* OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
* IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* The views and conclusions contained in the software and documentation
* are those of the authors and should not be interpreted as representing
* official policies, either expressed or implied, of the authors.
*/
/**
* Expand the S-box tables.
*
* @private
*/
'use strict';
Object.defineProperty(exports, '__esModule', {
value: true
});
var _createClass = (function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ('value' in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; })();
function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError('Cannot call a class as a function'); } }
var precompute = function precompute() {
var tables = [[[], [], [], [], []], [[], [], [], [], []]];
var encTable = tables[0];
var decTable = tables[1];
var sbox = encTable[4];
var sboxInv = decTable[4];
var i = undefined;
var x = undefined;
var xInv = undefined;
var d = [];
var th = [];
var x2 = undefined;
var x4 = undefined;
var x8 = undefined;
var s = undefined;
var tEnc = undefined;
var tDec = undefined;
// Compute double and third tables
for (i = 0; i < 256; i++) {
th[(d[i] = i << 1 ^ (i >> 7) * 283) ^ i] = i;
}
for (x = xInv = 0; !sbox[x]; x ^= x2 || 1, xInv = th[xInv] || 1) {
// Compute sbox
s = xInv ^ xInv << 1 ^ xInv << 2 ^ xInv << 3 ^ xInv << 4;
s = s >> 8 ^ s & 255 ^ 99;
sbox[x] = s;
sboxInv[s] = x;
// Compute MixColumns
x8 = d[x4 = d[x2 = d[x]]];
tDec = x8 * 0x1010101 ^ x4 * 0x10001 ^ x2 * 0x101 ^ x * 0x1010100;
tEnc = d[s] * 0x101 ^ s * 0x1010100;
for (i = 0; i < 4; i++) {
encTable[i][x] = tEnc = tEnc << 24 ^ tEnc >>> 8;
decTable[i][s] = tDec = tDec << 24 ^ tDec >>> 8;
}
}
// Compactify. Considerable speedup on Firefox.
for (i = 0; i < 5; i++) {
encTable[i] = encTable[i].slice(0);
decTable[i] = decTable[i].slice(0);
}
return tables;
};
var aesTables = null;
/**
* Schedule out an AES key for both encryption and decryption. This
* is a low-level class. Use a cipher mode to do bulk encryption.
*
* @class AES
* @param key {Array} The key as an array of 4, 6 or 8 words.
*/
var AES = (function () {
function AES(key) {
_classCallCheck(this, AES);
/**
* The expanded S-box and inverse S-box tables. These will be computed
* on the client so that we don't have to send them down the wire.
*
* There are two tables, _tables[0] is for encryption and
* _tables[1] is for decryption.
*
* The first 4 sub-tables are the expanded S-box with MixColumns. The
* last (_tables[01][4]) is the S-box itself.
*
* @private
*/
// if we have yet to precompute the S-box tables
// do so now
if (!aesTables) {
aesTables = precompute();
}
// then make a copy of that object for use
this._tables = [[aesTables[0][0].slice(), aesTables[0][1].slice(), aesTables[0][2].slice(), aesTables[0][3].slice(), aesTables[0][4].slice()], [aesTables[1][0].slice(), aesTables[1][1].slice(), aesTables[1][2].slice(), aesTables[1][3].slice(), aesTables[1][4].slice()]];
var i = undefined;
var j = undefined;
var tmp = undefined;
var encKey = undefined;
var decKey = undefined;
var sbox = this._tables[0][4];
var decTable = this._tables[1];
var keyLen = key.length;
var rcon = 1;
if (keyLen !== 4 && keyLen !== 6 && keyLen !== 8) {
throw new Error('Invalid aes key size');
}
encKey = key.slice(0);
decKey = [];
this._key = [encKey, decKey];
// schedule encryption keys
for (i = keyLen; i < 4 * keyLen + 28; i++) {
tmp = encKey[i - 1];
// apply sbox
if (i % keyLen === 0 || keyLen === 8 && i % keyLen === 4) {
tmp = sbox[tmp >>> 24] << 24 ^ sbox[tmp >> 16 & 255] << 16 ^ sbox[tmp >> 8 & 255] << 8 ^ sbox[tmp & 255];
// shift rows and add rcon
if (i % keyLen === 0) {
tmp = tmp << 8 ^ tmp >>> 24 ^ rcon << 24;
rcon = rcon << 1 ^ (rcon >> 7) * 283;
}
}
encKey[i] = encKey[i - keyLen] ^ tmp;
}
// schedule decryption keys
for (j = 0; i; j++, i--) {
tmp = encKey[j & 3 ? i : i - 4];
if (i <= 4 || j < 4) {
decKey[j] = tmp;
} else {
decKey[j] = decTable[0][sbox[tmp >>> 24]] ^ decTable[1][sbox[tmp >> 16 & 255]] ^ decTable[2][sbox[tmp >> 8 & 255]] ^ decTable[3][sbox[tmp & 255]];
}
}
}
/**
* Decrypt 16 bytes, specified as four 32-bit words.
*
* @param {Number} encrypted0 the first word to decrypt
* @param {Number} encrypted1 the second word to decrypt
* @param {Number} encrypted2 the third word to decrypt
* @param {Number} encrypted3 the fourth word to decrypt
* @param {Int32Array} out the array to write the decrypted words
* into
* @param {Number} offset the offset into the output array to start
* writing results
* @return {Array} The plaintext.
*/
_createClass(AES, [{
key: 'decrypt',
value: function decrypt(encrypted0, encrypted1, encrypted2, encrypted3, out, offset) {
var key = this._key[1];
// state variables a,b,c,d are loaded with pre-whitened data
var a = encrypted0 ^ key[0];
var b = encrypted3 ^ key[1];
var c = encrypted2 ^ key[2];
var d = encrypted1 ^ key[3];
var a2 = undefined;
var b2 = undefined;
var c2 = undefined;
// key.length === 2 ?
var nInnerRounds = key.length / 4 - 2;
var i = undefined;
var kIndex = 4;
var table = this._tables[1];
// load up the tables
var table0 = table[0];
var table1 = table[1];
var table2 = table[2];
var table3 = table[3];
var sbox = table[4];
// Inner rounds. Cribbed from OpenSSL.
for (i = 0; i < nInnerRounds; i++) {
a2 = table0[a >>> 24] ^ table1[b >> 16 & 255] ^ table2[c >> 8 & 255] ^ table3[d & 255] ^ key[kIndex];
b2 = table0[b >>> 24] ^ table1[c >> 16 & 255] ^ table2[d >> 8 & 255] ^ table3[a & 255] ^ key[kIndex + 1];
c2 = table0[c >>> 24] ^ table1[d >> 16 & 255] ^ table2[a >> 8 & 255] ^ table3[b & 255] ^ key[kIndex + 2];
d = table0[d >>> 24] ^ table1[a >> 16 & 255] ^ table2[b >> 8 & 255] ^ table3[c & 255] ^ key[kIndex + 3];
kIndex += 4;
a = a2;b = b2;c = c2;
}
// Last round.
for (i = 0; i < 4; i++) {
out[(3 & -i) + offset] = sbox[a >>> 24] << 24 ^ sbox[b >> 16 & 255] << 16 ^ sbox[c >> 8 & 255] << 8 ^ sbox[d & 255] ^ key[kIndex++];
a2 = a;a = b;b = c;c = d;d = a2;
}
}
}]);
return AES;
})();
exports['default'] = AES;
module.exports = exports['default'];