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1// Adapted from Chris Veness' SHA1 code at
2// http://www.movable-type.co.uk/scripts/sha1.html
3'use strict';
4
5function f(s, x, y, z) {
6 switch (s) {
7 case 0: return (x & y) ^ (~x & z);
8 case 1: return x ^ y ^ z;
9 case 2: return (x & y) ^ (x & z) ^ (y & z);
10 case 3: return x ^ y ^ z;
11 }
12}
13
14function ROTL(x, n) {
15 return (x << n) | (x>>> (32 - n));
16}
17
18function sha1(bytes) {
19 var K = [0x5a827999, 0x6ed9eba1, 0x8f1bbcdc, 0xca62c1d6];
20 var H = [0x67452301, 0xefcdab89, 0x98badcfe, 0x10325476, 0xc3d2e1f0];
21
22 if (typeof(bytes) == 'string') {
23 var msg = unescape(encodeURIComponent(bytes)); // UTF8 escape
24 bytes = new Array(msg.length);
25 for (var i = 0; i < msg.length; i++) bytes[i] = msg.charCodeAt(i);
26 }
27
28 bytes.push(0x80);
29
30 var l = bytes.length/4 + 2;
31 var N = Math.ceil(l/16);
32 var M = new Array(N);
33
34 for (var i=0; i<N; i++) {
35 M[i] = new Array(16);
36 for (var j=0; j<16; j++) {
37 M[i][j] =
38 bytes[i * 64 + j * 4] << 24 |
39 bytes[i * 64 + j * 4 + 1] << 16 |
40 bytes[i * 64 + j * 4 + 2] << 8 |
41 bytes[i * 64 + j * 4 + 3];
42 }
43 }
44
45 M[N - 1][14] = ((bytes.length - 1) * 8) /
46 Math.pow(2, 32); M[N - 1][14] = Math.floor(M[N - 1][14]);
47 M[N - 1][15] = ((bytes.length - 1) * 8) & 0xffffffff;
48
49 for (var i=0; i<N; i++) {
50 var W = new Array(80);
51
52 for (var t=0; t<16; t++) W[t] = M[i][t];
53 for (var t=16; t<80; t++) {
54 W[t] = ROTL(W[t - 3] ^ W[t - 8] ^ W[t - 14] ^ W[t - 16], 1);
55 }
56
57 var a = H[0];
58 var b = H[1];
59 var c = H[2];
60 var d = H[3];
61 var e = H[4];
62
63 for (var t=0; t<80; t++) {
64 var s = Math.floor(t/20);
65 var T = ROTL(a, 5) + f(s, b, c, d) + e + K[s] + W[t] >>> 0;
66 e = d;
67 d = c;
68 c = ROTL(b, 30) >>> 0;
69 b = a;
70 a = T;
71 }
72
73 H[0] = (H[0] + a) >>> 0;
74 H[1] = (H[1] + b) >>> 0;
75 H[2] = (H[2] + c) >>> 0;
76 H[3] = (H[3] + d) >>> 0;
77 H[4] = (H[4] + e) >>> 0;
78 }
79
80 return [
81 H[0] >> 24 & 0xff, H[0] >> 16 & 0xff, H[0] >> 8 & 0xff, H[0] & 0xff,
82 H[1] >> 24 & 0xff, H[1] >> 16 & 0xff, H[1] >> 8 & 0xff, H[1] & 0xff,
83 H[2] >> 24 & 0xff, H[2] >> 16 & 0xff, H[2] >> 8 & 0xff, H[2] & 0xff,
84 H[3] >> 24 & 0xff, H[3] >> 16 & 0xff, H[3] >> 8 & 0xff, H[3] & 0xff,
85 H[4] >> 24 & 0xff, H[4] >> 16 & 0xff, H[4] >> 8 & 0xff, H[4] & 0xff
86 ];
87}
88
89module.exports = sha1;