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- /*
- * 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('inherits')
- var Hash = require('./hash')
- var Buffer = require('safe-buffer').Buffer
-
- var K = [
- 0x5a827999, 0x6ed9eba1, 0x8f1bbcdc | 0, 0xca62c1d6 | 0
- ]
-
- var W = new Array(80)
-
- function Sha1 () {
- this.init()
- this._w = W
-
- Hash.call(this, 64, 56)
- }
-
- inherits(Sha1, Hash)
-
- Sha1.prototype.init = function () {
- this._a = 0x67452301
- this._b = 0xefcdab89
- this._c = 0x98badcfe
- this._d = 0x10325476
- this._e = 0xc3d2e1f0
-
- return this
- }
-
- function rotl1 (num) {
- return (num << 1) | (num >>> 31)
- }
-
- function rotl5 (num) {
- return (num << 5) | (num >>> 27)
- }
-
- function rotl30 (num) {
- return (num << 30) | (num >>> 2)
- }
-
- function ft (s, b, c, d) {
- if (s === 0) return (b & c) | ((~b) & d)
- if (s === 2) return (b & c) | (b & d) | (c & d)
- return b ^ c ^ d
- }
-
- Sha1.prototype._update = function (M) {
- var W = this._w
-
- var a = this._a | 0
- var b = this._b | 0
- var c = this._c | 0
- var d = this._d | 0
- var e = this._e | 0
-
- for (var i = 0; i < 16; ++i) W[i] = M.readInt32BE(i * 4)
- for (; i < 80; ++i) W[i] = rotl1(W[i - 3] ^ W[i - 8] ^ W[i - 14] ^ W[i - 16])
-
- for (var j = 0; j < 80; ++j) {
- var s = ~~(j / 20)
- var t = (rotl5(a) + ft(s, b, c, d) + e + W[j] + K[s]) | 0
-
- e = d
- d = c
- c = rotl30(b)
- b = a
- a = t
- }
-
- this._a = (a + this._a) | 0
- this._b = (b + this._b) | 0
- this._c = (c + this._c) | 0
- this._d = (d + this._d) | 0
- this._e = (e + this._e) | 0
- }
-
- Sha1.prototype._hash = function () {
- var H = Buffer.allocUnsafe(20)
-
- H.writeInt32BE(this._a | 0, 0)
- H.writeInt32BE(this._b | 0, 4)
- H.writeInt32BE(this._c | 0, 8)
- H.writeInt32BE(this._d | 0, 12)
- H.writeInt32BE(this._e | 0, 16)
-
- return H
- }
-
- module.exports = Sha1
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