sha1-browser.js (2338B)
1 // Adapted from Chris Veness' SHA1 code at 2 // http://www.movable-type.co.uk/scripts/sha1.html 3 'use strict'; 4 5 function 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 14 function ROTL(x, n) { 15 return (x << n) | (x>>> (32 - n)); 16 } 17 18 function 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 89 module.exports = sha1;