aes.js
8.43 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
;(function (root, factory, undef) {
if (typeof exports === "object") {
// CommonJS
module.exports = exports = factory(require("./core"), require("./enc-base64"), require("./md5"), require("./evpkdf"), require("./cipher-core"));
}
else if (typeof define === "function" && define.amd) {
// AMD
define(["./core", "./enc-base64", "./md5", "./evpkdf", "./cipher-core"], factory);
}
else {
// Global (browser)
factory(root.CryptoJS);
}
}(this, function (CryptoJS) {
(function () {
// Shortcuts
var C = CryptoJS;
var C_lib = C.lib;
var BlockCipher = C_lib.BlockCipher;
var C_algo = C.algo;
// Lookup tables
var SBOX = [];
var INV_SBOX = [];
var SUB_MIX_0 = [];
var SUB_MIX_1 = [];
var SUB_MIX_2 = [];
var SUB_MIX_3 = [];
var INV_SUB_MIX_0 = [];
var INV_SUB_MIX_1 = [];
var INV_SUB_MIX_2 = [];
var INV_SUB_MIX_3 = [];
// Compute lookup tables
(function () {
// Compute double table
var d = [];
for (var i = 0; i < 256; i++) {
if (i < 128) {
d[i] = i << 1;
} else {
d[i] = (i << 1) ^ 0x11b;
}
}
// 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
var 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;
// Compute next counter
if (!x) {
x = xi = 1;
} else {
x = x2 ^ d[d[d[x8 ^ x2]]];
xi ^= d[d[xi]];
}
}
}());
// Precomputed Rcon lookup
var RCON = [0x00, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36];
/**
* AES block cipher algorithm.
*/
var AES = C_algo.AES = BlockCipher.extend({
_doReset: function () {
// Skip reset of nRounds has been set before and key did not change
if (this._nRounds && this._keyPriorReset === this._key) {
return;
}
// Shortcuts
var key = this._keyPriorReset = this._key;
var keyWords = key.words;
var keySize = key.sigBytes / 4;
// Compute number of rounds
var nRounds = this._nRounds = keySize + 6;
// Compute number of key schedule rows
var ksRows = (nRounds + 1) * 4;
// Compute key schedule
var keySchedule = this._keySchedule = [];
for (var ksRow = 0; ksRow < ksRows; ksRow++) {
if (ksRow < keySize) {
keySchedule[ksRow] = keyWords[ksRow];
} else {
var t = keySchedule[ksRow - 1];
if (!(ksRow % keySize)) {
// Rot word
t = (t << 8) | (t >>> 24);
// Sub word
t = (SBOX[t >>> 24] << 24) | (SBOX[(t >>> 16) & 0xff] << 16) | (SBOX[(t >>> 8) & 0xff] << 8) | SBOX[t & 0xff];
// Mix Rcon
t ^= RCON[(ksRow / keySize) | 0] << 24;
} else if (keySize > 6 && ksRow % keySize == 4) {
// Sub word
t = (SBOX[t >>> 24] << 24) | (SBOX[(t >>> 16) & 0xff] << 16) | (SBOX[(t >>> 8) & 0xff] << 8) | SBOX[t & 0xff];
}
keySchedule[ksRow] = keySchedule[ksRow - keySize] ^ t;
}
}
// Compute inv key schedule
var invKeySchedule = this._invKeySchedule = [];
for (var invKsRow = 0; invKsRow < ksRows; invKsRow++) {
var ksRow = ksRows - invKsRow;
if (invKsRow % 4) {
var t = keySchedule[ksRow];
} else {
var t = keySchedule[ksRow - 4];
}
if (invKsRow < 4 || ksRow <= 4) {
invKeySchedule[invKsRow] = t;
} else {
invKeySchedule[invKsRow] = INV_SUB_MIX_0[SBOX[t >>> 24]] ^ INV_SUB_MIX_1[SBOX[(t >>> 16) & 0xff]] ^
INV_SUB_MIX_2[SBOX[(t >>> 8) & 0xff]] ^ INV_SUB_MIX_3[SBOX[t & 0xff]];
}
}
},
encryptBlock: function (M, offset) {
this._doCryptBlock(M, offset, this._keySchedule, SUB_MIX_0, SUB_MIX_1, SUB_MIX_2, SUB_MIX_3, SBOX);
},
decryptBlock: function (M, offset) {
// Swap 2nd and 4th rows
var t = M[offset + 1];
M[offset + 1] = M[offset + 3];
M[offset + 3] = t;
this._doCryptBlock(M, offset, this._invKeySchedule, INV_SUB_MIX_0, INV_SUB_MIX_1, INV_SUB_MIX_2, INV_SUB_MIX_3, INV_SBOX);
// Inv swap 2nd and 4th rows
var t = M[offset + 1];
M[offset + 1] = M[offset + 3];
M[offset + 3] = t;
},
_doCryptBlock: function (M, offset, keySchedule, SUB_MIX_0, SUB_MIX_1, SUB_MIX_2, SUB_MIX_3, SBOX) {
// Shortcut
var nRounds = this._nRounds;
// Get input, add round key
var s0 = M[offset] ^ keySchedule[0];
var s1 = M[offset + 1] ^ keySchedule[1];
var s2 = M[offset + 2] ^ keySchedule[2];
var s3 = M[offset + 3] ^ keySchedule[3];
// Key schedule row counter
var ksRow = 4;
// Rounds
for (var round = 1; round < nRounds; round++) {
// Shift rows, sub bytes, mix columns, add round key
var t0 = SUB_MIX_0[s0 >>> 24] ^ SUB_MIX_1[(s1 >>> 16) & 0xff] ^ SUB_MIX_2[(s2 >>> 8) & 0xff] ^ SUB_MIX_3[s3 & 0xff] ^ keySchedule[ksRow++];
var t1 = SUB_MIX_0[s1 >>> 24] ^ SUB_MIX_1[(s2 >>> 16) & 0xff] ^ SUB_MIX_2[(s3 >>> 8) & 0xff] ^ SUB_MIX_3[s0 & 0xff] ^ keySchedule[ksRow++];
var t2 = SUB_MIX_0[s2 >>> 24] ^ SUB_MIX_1[(s3 >>> 16) & 0xff] ^ SUB_MIX_2[(s0 >>> 8) & 0xff] ^ SUB_MIX_3[s1 & 0xff] ^ keySchedule[ksRow++];
var t3 = SUB_MIX_0[s3 >>> 24] ^ SUB_MIX_1[(s0 >>> 16) & 0xff] ^ SUB_MIX_2[(s1 >>> 8) & 0xff] ^ SUB_MIX_3[s2 & 0xff] ^ keySchedule[ksRow++];
// Update state
s0 = t0;
s1 = t1;
s2 = t2;
s3 = t3;
}
// Shift rows, sub bytes, add round key
var t0 = ((SBOX[s0 >>> 24] << 24) | (SBOX[(s1 >>> 16) & 0xff] << 16) | (SBOX[(s2 >>> 8) & 0xff] << 8) | SBOX[s3 & 0xff]) ^ keySchedule[ksRow++];
var t1 = ((SBOX[s1 >>> 24] << 24) | (SBOX[(s2 >>> 16) & 0xff] << 16) | (SBOX[(s3 >>> 8) & 0xff] << 8) | SBOX[s0 & 0xff]) ^ keySchedule[ksRow++];
var t2 = ((SBOX[s2 >>> 24] << 24) | (SBOX[(s3 >>> 16) & 0xff] << 16) | (SBOX[(s0 >>> 8) & 0xff] << 8) | SBOX[s1 & 0xff]) ^ keySchedule[ksRow++];
var t3 = ((SBOX[s3 >>> 24] << 24) | (SBOX[(s0 >>> 16) & 0xff] << 16) | (SBOX[(s1 >>> 8) & 0xff] << 8) | SBOX[s2 & 0xff]) ^ keySchedule[ksRow++];
// Set output
M[offset] = t0;
M[offset + 1] = t1;
M[offset + 2] = t2;
M[offset + 3] = t3;
},
keySize: 256/32
});
/**
* Shortcut functions to the cipher's object interface.
*
* @example
*
* var ciphertext = CryptoJS.AES.encrypt(message, key, cfg);
* var plaintext = CryptoJS.AES.decrypt(ciphertext, key, cfg);
*/
C.AES = BlockCipher._createHelper(AES);
}());
return CryptoJS.AES;
}));