d2-ui
Version:
139 lines (113 loc) • 3.21 kB
JavaScript
/*
* A JavaScript implementation of the Secure Hash Algorithm, SHA-1, as defined
* in FIPS PUB 180-1
* Version 2.1a Copyright Paul Johnston 2000 - 2002.
* Other contributors: Greg Holt, Andrew Kepert, Ydnar, Lostinet
* Distributed under the BSD License
* See http://pajhome.org.uk/crypt/md5 for details.
*/
var inherits = require('util').inherits
module.exports = function (Buffer, Hash) {
var A = 0|0
var B = 4|0
var C = 8|0
var D = 12|0
var E = 16|0
var W = new (typeof Int32Array === 'undefined' ? Array : Int32Array)(80)
var POOL = []
function Sha1 () {
if(POOL.length)
return POOL.pop().init()
if(!(this instanceof Sha1)) return new Sha1()
this._w = W
Hash.call(this, 16*4, 14*4)
this._h = null
this.init()
}
inherits(Sha1, Hash)
Sha1.prototype.init = function () {
this._a = 0x67452301
this._b = 0xefcdab89
this._c = 0x98badcfe
this._d = 0x10325476
this._e = 0xc3d2e1f0
Hash.prototype.init.call(this)
return this
}
Sha1.prototype._POOL = POOL
Sha1.prototype._update = function (X) {
var a, b, c, d, e, _a, _b, _c, _d, _e
a = _a = this._a
b = _b = this._b
c = _c = this._c
d = _d = this._d
e = _e = this._e
var w = this._w
for(var j = 0; j < 80; j++) {
var W = w[j] = j < 16 ? X.readInt32BE(j*4)
: rol(w[j - 3] ^ w[j - 8] ^ w[j - 14] ^ w[j - 16], 1)
var t = add(
add(rol(a, 5), sha1_ft(j, b, c, d)),
add(add(e, W), sha1_kt(j))
)
e = d
d = c
c = rol(b, 30)
b = a
a = t
}
this._a = add(a, _a)
this._b = add(b, _b)
this._c = add(c, _c)
this._d = add(d, _d)
this._e = add(e, _e)
}
Sha1.prototype._hash = function () {
if(POOL.length < 100) POOL.push(this)
var H = new Buffer(20)
//console.log(this._a|0, this._b|0, this._c|0, this._d|0, this._e|0)
H.writeInt32BE(this._a|0, A)
H.writeInt32BE(this._b|0, B)
H.writeInt32BE(this._c|0, C)
H.writeInt32BE(this._d|0, D)
H.writeInt32BE(this._e|0, E)
return H
}
/*
* Perform the appropriate triplet combination function for the current
* iteration
*/
function sha1_ft(t, b, c, d) {
if(t < 20) return (b & c) | ((~b) & d);
if(t < 40) return b ^ c ^ d;
if(t < 60) return (b & c) | (b & d) | (c & d);
return b ^ c ^ d;
}
/*
* Determine the appropriate additive constant for the current iteration
*/
function sha1_kt(t) {
return (t < 20) ? 1518500249 : (t < 40) ? 1859775393 :
(t < 60) ? -1894007588 : -899497514;
}
/*
* Add integers, wrapping at 2^32. This uses 16-bit operations internally
* to work around bugs in some JS interpreters.
* //dominictarr: this is 10 years old, so maybe this can be dropped?)
*
*/
function add(x, y) {
return (x + y ) | 0
//lets see how this goes on testling.
// var lsw = (x & 0xFFFF) + (y & 0xFFFF);
// var msw = (x >> 16) + (y >> 16) + (lsw >> 16);
// return (msw << 16) | (lsw & 0xFFFF);
}
/*
* Bitwise rotate a 32-bit number to the left.
*/
function rol(num, cnt) {
return (num << cnt) | (num >>> (32 - cnt));
}
return Sha1
}