This repository has been archived by the owner on Aug 1, 2024. It is now read-only.
-
Notifications
You must be signed in to change notification settings - Fork 1k
/
sha2.js
324 lines (278 loc) · 9.47 KB
/
sha2.js
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
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
/**
* @license
* Copyright The Closure Library Authors.
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @fileoverview Base class for SHA-2 cryptographic hash.
*
* Variable names follow the notation in FIPS PUB 180-3:
* http://csrc.nist.gov/publications/fips/fips180-3/fips180-3_final.pdf.
*
* Some code similar to SHA1 are borrowed from sha1.js written by mschilder@.
*/
goog.provide('goog.crypt.Sha2');
goog.require('goog.array');
goog.require('goog.asserts');
goog.require('goog.crypt.Hash');
/**
* SHA-2 cryptographic hash constructor.
* This constructor should not be used directly to create the object. Rather,
* one should use the constructor of the sub-classes.
* @param {number} numHashBlocks The size of output in 16-byte blocks.
* @param {!Array<number>} initHashBlocks The hash-specific initialization
* @constructor
* @extends {goog.crypt.Hash}
* @struct
*/
goog.crypt.Sha2 = function(numHashBlocks, initHashBlocks) {
'use strict';
goog.crypt.Sha2.base(this, 'constructor');
/** @const {number} */
this.blockSize = goog.crypt.Sha2.BLOCKSIZE_;
/**
* A chunk holding the currently processed message bytes. Once the chunk has
* 64 bytes, we feed it into computeChunk_ function and reset this.chunk_.
* @private {!Array<number>|!Uint8Array}
*/
this.chunk_ = goog.global['Uint8Array'] ? new Uint8Array(this.blockSize) :
new Array(this.blockSize);
/**
* Current number of bytes in this.chunk_.
* @private {number}
*/
this.inChunk_ = 0;
/**
* Total number of bytes in currently processed message.
* @private {number}
*/
this.total_ = 0;
/**
* Holds the previous values of accumulated hash a-h in the computeChunk_
* function.
* @private {!Array<number>|!Int32Array}
*/
this.hash_ = [];
/**
* The number of output hash blocks (each block is 4 bytes long).
* @private {number}
*/
this.numHashBlocks_ = numHashBlocks;
/**
* @private {!Array<number>} initHashBlocks
*/
this.initHashBlocks_ = initHashBlocks;
/**
* Temporary array used in chunk computation. Allocate here as a
* member rather than as a local within computeChunk_() as a
* performance optimization to reduce the number of allocations and
* reduce garbage collection.
* @private {!Int32Array|!Array<number>}
*/
this.w_ = goog.global['Int32Array'] ? new Int32Array(64) : new Array(64);
if (goog.crypt.Sha2.Kx_ === undefined) {
// This is the first time this constructor has been called.
if (goog.global['Int32Array']) {
// Typed arrays exist
goog.crypt.Sha2.Kx_ = new Int32Array(goog.crypt.Sha2.K_);
} else {
// Typed arrays do not exist
goog.crypt.Sha2.Kx_ = goog.crypt.Sha2.K_;
}
}
this.reset();
};
goog.inherits(goog.crypt.Sha2, goog.crypt.Hash);
/**
* The block size
* @private {number}
*/
goog.crypt.Sha2.BLOCKSIZE_ = 512 / 8;
/**
* Contains data needed to pad messages less than BLOCK_SIZE_ bytes.
* @private {!Array<number>}
*/
goog.crypt.Sha2.PADDING_ =
[].concat(128, goog.array.repeat(0, goog.crypt.Sha2.BLOCKSIZE_ - 1));
/** @override */
goog.crypt.Sha2.prototype.reset = function() {
'use strict';
this.inChunk_ = 0;
this.total_ = 0;
this.hash_ = goog.global['Int32Array'] ?
new Int32Array(this.initHashBlocks_) :
goog.array.clone(this.initHashBlocks_);
};
/**
* Helper function to compute the hashes for a given 512-bit message chunk.
* @private
*/
goog.crypt.Sha2.prototype.computeChunk_ = function() {
'use strict';
var chunk = this.chunk_;
goog.asserts.assert(chunk.length == this.blockSize);
var rounds = 64;
// Divide the chunk into 16 32-bit-words.
var w = this.w_;
var index = 0;
var offset = 0;
while (offset < chunk.length) {
w[index++] = (chunk[offset] << 24) | (chunk[offset + 1] << 16) |
(chunk[offset + 2] << 8) | (chunk[offset + 3]);
offset = index * 4;
}
// Extend the w[] array to be the number of rounds.
for (var i = 16; i < rounds; i++) {
var w_15 = w[i - 15] | 0;
var s0 = ((w_15 >>> 7) | (w_15 << 25)) ^ ((w_15 >>> 18) | (w_15 << 14)) ^
(w_15 >>> 3);
var w_2 = w[i - 2] | 0;
var s1 = ((w_2 >>> 17) | (w_2 << 15)) ^ ((w_2 >>> 19) | (w_2 << 13)) ^
(w_2 >>> 10);
// As a performance optimization, construct the sum a pair at a time
// with casting to integer (bitwise OR) to eliminate unnecessary
// double<->integer conversions.
var partialSum1 = ((w[i - 16] | 0) + s0) | 0;
var partialSum2 = ((w[i - 7] | 0) + s1) | 0;
w[i] = (partialSum1 + partialSum2) | 0;
}
var a = this.hash_[0] | 0;
var b = this.hash_[1] | 0;
var c = this.hash_[2] | 0;
var d = this.hash_[3] | 0;
var e = this.hash_[4] | 0;
var f = this.hash_[5] | 0;
var g = this.hash_[6] | 0;
var h = this.hash_[7] | 0;
for (var i = 0; i < rounds; i++) {
var S0 = ((a >>> 2) | (a << 30)) ^ ((a >>> 13) | (a << 19)) ^
((a >>> 22) | (a << 10));
var maj = ((a & b) ^ (a & c) ^ (b & c));
var t2 = (S0 + maj) | 0;
var S1 = ((e >>> 6) | (e << 26)) ^ ((e >>> 11) | (e << 21)) ^
((e >>> 25) | (e << 7));
var ch = ((e & f) ^ ((~e) & g));
// As a performance optimization, construct the sum a pair at a time
// with casting to integer (bitwise OR) to eliminate unnecessary
// double<->integer conversions.
var partialSum1 = (h + S1) | 0;
var partialSum2 = (ch + (goog.crypt.Sha2.Kx_[i] | 0)) | 0;
var partialSum3 = (partialSum2 + (w[i] | 0)) | 0;
var t1 = (partialSum1 + partialSum3) | 0;
h = g;
g = f;
f = e;
e = (d + t1) | 0;
d = c;
c = b;
b = a;
a = (t1 + t2) | 0;
}
this.hash_[0] = (this.hash_[0] + a) | 0;
this.hash_[1] = (this.hash_[1] + b) | 0;
this.hash_[2] = (this.hash_[2] + c) | 0;
this.hash_[3] = (this.hash_[3] + d) | 0;
this.hash_[4] = (this.hash_[4] + e) | 0;
this.hash_[5] = (this.hash_[5] + f) | 0;
this.hash_[6] = (this.hash_[6] + g) | 0;
this.hash_[7] = (this.hash_[7] + h) | 0;
};
/** @override */
goog.crypt.Sha2.prototype.update = function(message, opt_length) {
'use strict';
if (opt_length === undefined) {
opt_length = message.length;
}
// Process the message from left to right up to |opt_length| bytes.
// When we get a 512-bit chunk, compute the hash of it and reset
// this.chunk_. The message might not be multiple of 512 bits so we
// might end up with a chunk that is less than 512 bits. We store
// such partial chunk in this.chunk_ and it will be filled up later
// in digest().
var n = 0;
var inChunk = this.inChunk_;
// The input message could be either byte array of string.
if (typeof message === 'string') {
while (n < opt_length) {
this.chunk_[inChunk++] = message.charCodeAt(n++);
if (inChunk == this.blockSize) {
this.computeChunk_();
inChunk = 0;
}
}
} else if (goog.isArrayLike(message)) {
while (n < opt_length) {
var b = message[n++];
if (!('number' == typeof b && 0 <= b && 255 >= b && b == (b | 0))) {
throw new Error('message must be a byte array');
}
this.chunk_[inChunk++] = b;
if (inChunk == this.blockSize) {
this.computeChunk_();
inChunk = 0;
}
}
} else {
throw new Error('message must be string or array');
}
// Record the current bytes in chunk to support partial update.
this.inChunk_ = inChunk;
// Record total message bytes we have processed so far.
this.total_ += opt_length;
};
/** @override */
goog.crypt.Sha2.prototype.digest = function() {
'use strict';
var digest = [];
var totalBits = this.total_ * 8;
// Append pad 0x80 0x00*.
if (this.inChunk_ < 56) {
this.update(goog.crypt.Sha2.PADDING_, 56 - this.inChunk_);
} else {
this.update(
goog.crypt.Sha2.PADDING_, this.blockSize - (this.inChunk_ - 56));
}
// Append # bits in the 64-bit big-endian format.
for (var i = 63; i >= 56; i--) {
this.chunk_[i] = totalBits & 255;
totalBits /= 256; // Don't use bit-shifting here!
}
this.computeChunk_();
// Finally, output the result digest.
var n = 0;
for (var i = 0; i < this.numHashBlocks_; i++) {
for (var j = 24; j >= 0; j -= 8) {
digest[n++] = ((this.hash_[i] >> j) & 255);
}
}
return digest;
};
/**
* Constants used in SHA-2.
* @const
* @private {!Array<number>}
*/
goog.crypt.Sha2.K_ = [
0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1,
0x923f82a4, 0xab1c5ed5, 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174, 0xe49b69c1, 0xefbe4786,
0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147,
0x06ca6351, 0x14292967, 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85, 0xa2bfe8a1, 0xa81a664b,
0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a,
0x5b9cca4f, 0x682e6ff3, 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
];
/**
* Sha2.K as an Int32Array if this JS supports typed arrays; otherwise,
* the same array as Sha2.K.
*
* The compiler cannot remove an Int32Array, even if it is not needed
* (There are certain cases where creating an Int32Array is not
* side-effect free). Instead, the first time we construct a Sha2
* instance, we convert or assign Sha2.K as appropriate.
* @private {undefined|!Array<number>|!Int32Array}
*/
goog.crypt.Sha2.Kx_;