ubid
Version:
A browser identification library.
283 lines (226 loc) • 8.76 kB
JavaScript
;
var async = require( 'async' );
var uuid = require( 'uuid' );
module.exports = {};
var STORAGE_KEY = 'ubid:signaturedata';
module.exports.get = function( callback, storageLayer ) {
var ids = null;
var storageSupported = false;
async.series( [
// check for the item in storage
function( next ) {
if ( !storageLayer || !storageLayer.getItem ) {
next();
return;
}
var jsonIDs = storageLayer.getItem( STORAGE_KEY );
try {
ids = JSON.parse( jsonIDs );
}
catch( ex ) {
ids = null;
}
storageSupported = true;
next();
},
// generate ids if they were not read out of storage
function( next ) {
if ( ids ) {
next();
return;
}
getSignatureData( function( error, _ids ) {
ids = _ids;
next( error );
} );
},
// store ids into storage
function( next ) {
if ( !storageSupported ) {
next();
return;
}
storageLayer.setItem( STORAGE_KEY, JSON.stringify( ids ) );
next();
}
], function( error ) {
if ( ids ) {
ids.storageSupported = storageSupported;
}
callback( error, ids );
} );
};
function getSignatureData( callback ) {
var signatureData = {};
async.parallel( [
getRandomID.bind( null, signatureData ),
getBrowserSignature.bind( null, signatureData ),
getCanvasSignature.bind( null, signatureData )
], function( error ) {
callback( error, signatureData );
} );
}
function getRandomID( signatureData, callback ) {
signatureData.random = {
signature: uuid.v4()
};
callback();
}
function getBrowserSignature( signatureData, callback ) {
var idString = navigator.userAgent + navigator.language;
for ( var key in navigator.plugins ) {
var plugin = navigator.plugins[ key ];
idString += plugin.name + plugin.filename + plugin.description;
}
signatureData.browser = {
signature: SHA256( idString )
};
callback();
}
var CANVAS_TEXT = "AaBbCcDdEeFfGgHhIiJjKkLlMmNnOoPpQqRrSsTtUuVvWwXxYyZz 1234567890 !@#$%^&*()_-+=";
var CANVAS_FONT_SIZE = 16;
var CANVAS_FONT_FACE = 'Arial';
function getCanvasSignature( signatureData, callback ) {
// based on:
// https://www.browserleaks.com/canvas#how-does-it-work
// https://github.com/kmowery/canvas-fingerprinting
signatureData.canvas = {
signature: null
};
var canvas = document.createElement( 'canvas' );
if ( !canvas || !canvas.getContext ) {
callback();
return;
}
var width = CANVAS_FONT_SIZE * ( CANVAS_TEXT.length + 2 );
var height = CANVAS_FONT_SIZE * 2;
canvas.setAttribute( 'width', width );
canvas.setAttribute( 'height', height );
var ctx = canvas.getContext( '2d' );
if ( !ctx || typeof( ctx.fillText ) !== 'function' ) {
callback();
return;
}
try {
ctx.font = CANVAS_FONT_SIZE + 'px \'' + CANVAS_FONT_FACE + '\'';
ctx.textBaseline = 'middle';
ctx.textAlign = 'center';
ctx.fillStyle = "#f60";
ctx.fillRect( ( ( 3 * width ) / 8 ), 0, width / 4, height );
ctx.fillStyle = "#069";
ctx.fillText( CANVAS_TEXT, width / 2, height / 2 );
ctx.fillStyle = "rgba(102, 204, 0, 0.7)";
ctx.fillText( CANVAS_TEXT, ( width / 2 ) + 2, ( height / 2 ) + 2 );
var base64png = canvas.toDataURL( 'image/png' );
signatureData.canvas.signature = SHA256( base64png );
callback();
} catch (ex) {
callback();
return;
}
}
/**
*
* Secure Hash Algorithm (SHA256)
* http://www.webtoolkit.info/
*
* Original code by Angel Marin, Paul Johnston.
*
**/
var HEX_TAB = "0123456789abcdef";
function SHA256( data ) {
var chrsz = 8;
function safe_add (x, y) {
var lsw = (x & 0xFFFF) + (y & 0xFFFF);
var msw = (x >> 16) + (y >> 16) + (lsw >> 16);
return (msw << 16) | (lsw & 0xFFFF);
}
function s( X, n ) { return ( X >>> n ) | (X << (32 - n)); }
function r( X, n ) { return ( X >>> n ); }
function ch(x, y, z) { return ((x & y) ^ ((~x) & z)); }
function maj(x, y, z) { return ((x & y) ^ (x & z) ^ (y & z)); }
function sigma0256(x) { return (s(x, 2) ^ s(x, 13) ^ s(x, 22)); }
function sigma1256(x) { return (s(x, 6) ^ s(x, 11) ^ s(x, 25)); }
function gamma0256(x) { return (s(x, 7) ^ s(x, 18) ^ r(x, 3)); }
function gamma1256(x) { return (s(x, 17) ^ s(x, 19) ^ r(x, 10)); }
function core_sha256 (m, l) {
var K = new Array(0x428A2F98, 0x71374491, 0xB5C0FBCF, 0xE9B5DBA5, 0x3956C25B, 0x59F111F1, 0x923F82A4, 0xAB1C5ED5, 0xD807AA98, 0x12835B01, 0x243185BE, 0x550C7DC3, 0x72BE5D74, 0x80DEB1FE, 0x9BDC06A7, 0xC19BF174, 0xE49B69C1, 0xEFBE4786, 0xFC19DC6, 0x240CA1CC, 0x2DE92C6F, 0x4A7484AA, 0x5CB0A9DC, 0x76F988DA, 0x983E5152, 0xA831C66D, 0xB00327C8, 0xBF597FC7, 0xC6E00BF3, 0xD5A79147, 0x6CA6351, 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);
var HASH = new Array(0x6A09E667, 0xBB67AE85, 0x3C6EF372, 0xA54FF53A, 0x510E527F, 0x9B05688C, 0x1F83D9AB, 0x5BE0CD19);
var W = new Array(64);
var a, b, c, d, e, f, g, h, i, j;
var T1, T2;
m[l >> 5] |= 0x80 << (24 - l % 32);
m[((l + 64 >> 9) << 4) + 15] = l;
for ( i = 0; i<m.length; i+=16 ) {
a = HASH[0];
b = HASH[1];
c = HASH[2];
d = HASH[3];
e = HASH[4];
f = HASH[5];
g = HASH[6];
h = HASH[7];
for ( j = 0; j<64; j++) {
if (j < 16) W[j] = m[j + i];
else W[j] = safe_add(safe_add(safe_add(gamma1256(W[j - 2]), W[j - 7]), gamma0256(W[j - 15])), W[j - 16]);
T1 = safe_add(safe_add(safe_add(safe_add(h, sigma1256(e)), ch(e, f, g)), K[j]), W[j]);
T2 = safe_add(sigma0256(a), maj(a, b, c));
h = g;
g = f;
f = e;
e = safe_add(d, T1);
d = c;
c = b;
b = a;
a = safe_add(T1, T2);
}
HASH[0] = safe_add(a, HASH[0]);
HASH[1] = safe_add(b, HASH[1]);
HASH[2] = safe_add(c, HASH[2]);
HASH[3] = safe_add(d, HASH[3]);
HASH[4] = safe_add(e, HASH[4]);
HASH[5] = safe_add(f, HASH[5]);
HASH[6] = safe_add(g, HASH[6]);
HASH[7] = safe_add(h, HASH[7]);
}
return HASH;
}
function str2binb (str) {
var bin = [];
var mask = (1 << chrsz) - 1;
for(var i = 0; i < str.length * chrsz; i += chrsz) {
bin[i>>5] |= (str.charCodeAt(i / chrsz) & mask) << (24 - i%32);
}
return bin;
}
function utf8Encode(string) {
string = string.replace(/\r\n/g,"\n");
var utftext = "";
for (var n = 0; n < string.length; n++) {
var c = string.charCodeAt(n);
if (c < 128) {
utftext += String.fromCharCode(c);
}
else if((c > 127) && (c < 2048)) {
utftext += String.fromCharCode((c >> 6) | 192);
utftext += String.fromCharCode((c & 63) | 128);
}
else {
utftext += String.fromCharCode((c >> 12) | 224);
utftext += String.fromCharCode(((c >> 6) & 63) | 128);
utftext += String.fromCharCode((c & 63) | 128);
}
}
return utftext;
}
function binb2hex (binarray) {
var str = "";
for(var i = 0; i < binarray.length * 4; i++) {
str += HEX_TAB.charAt((binarray[i>>2] >> ((3 - i%4)*8+4)) & 0xF) +
HEX_TAB.charAt((binarray[i>>2] >> ((3 - i%4)*8 )) & 0xF);
}
return str;
}
var utf = utf8Encode( data );
return binb2hex(core_sha256(str2binb(utf), utf.length * chrsz));
}