FIDO U2F component extension

chrome/browser/resources/cryptotoken/util.js

+// Copyright (c) 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Various string utility functions by mschilder@google.com
+'use strict';
+
+/**
+ * Converts a string to an array of bytes.
+ * @param {string} s The string to convert.
+ * @param {(Array|Uint8Array)=} bytes The Array-like object into which to store
+ *     the bytes. A new Array will be created if not provided.
+ * @return {(Array|Uint8Array)} An array of bytes representing the string.
+ */
+function UTIL_StringToBytes(s, bytes) {
+  bytes = bytes || new Array(s.length);
+  for (var i = 0; i < s.length; ++i)
+    bytes[i] = s.charCodeAt(i);
+  return bytes;
+}
+
+function UTIL_BytesToString(b) {
+  return String.fromCharCode.apply(null, b);
+}
+
+function UTIL_BytesToHex(b) {
+  if (!b) return '(null)';
+  var hexchars = '0123456789ABCDEF';
+  var hexrep = new Array(b.length * 2);
+
+  for (var i = 0; i < b.length; ++i) {
+    hexrep[i * 2 + 0] = hexchars.charAt((b[i] >> 4) & 15);
+    hexrep[i * 2 + 1] = hexchars.charAt(b[i] & 15);
+  }
+  return hexrep.join('');
+}
+
+function UTIL_BytesToHexWithSeparator(b, sep) {
+  var hexchars = '0123456789ABCDEF';
+  var stride = 2 + (sep ? 1 : 0);
+  var hexrep = new Array(b.length * stride);
+
+  for (var i = 0; i < b.length; ++i) {
+    if (sep) hexrep[i * stride + 0] = sep;
+    hexrep[i * stride + stride - 2] = hexchars.charAt((b[i] >> 4) & 15);
+    hexrep[i * stride + stride - 1] = hexchars.charAt(b[i] & 15);
+  }
+  return (sep ? hexrep.slice(1) : hexrep).join('');
+}
+
+function UTIL_HexToBytes(h) {
+  var hexchars = '0123456789ABCDEFabcdef';
+  var res = new Uint8Array(h.length / 2);
+  for (var i = 0; i < h.length; i += 2) {
+    if (hexchars.indexOf(h.substring(i, i + 1)) == -1) break;
+    res[i / 2] = parseInt(h.substring(i, i + 2), 16);
+  }
+  return res;
+}
+
+function UTIL_equalArrays(a, b) {
+  if (!a || !b) return false;
+  if (a.length != b.length) return false;
+  var accu = 0;
+  for (var i = 0; i < a.length; ++i)
+    accu |= a[i] ^ b[i];
+  return accu === 0;
+}
+
+function UTIL_ltArrays(a, b) {
+  if (a.length < b.length) return true;
+  if (a.length > b.length) return false;
+  for (var i = 0; i < a.length; ++i) {
+    if (a[i] < b[i]) return true;
+    if (a[i] > b[i]) return false;
+  }
+  return false;
+}
+
+function UTIL_gtArrays(a, b) {
+  return UTIL_ltArrays(b, a);
+}
+
+function UTIL_geArrays(a, b) {
+  return !UTIL_ltArrays(a, b);
+}
+
+function UTIL_unionArrays(a, b) {
+  var obj = {};
+  for (var i = 0; i < a.length; i++) {
+    obj[a[i]] = a[i];
+  }
+  for (var i = 0; i < b.length; i++) {
+    obj[b[i]] = b[i];
+  }
+  var union = [];
+  for (var k in obj) {
+    union.push(obj[k]);
+  }
+  return union;
+}
+
+function UTIL_getRandom(a) {
+  var tmp = new Array(a);
+  var rnd = new Uint8Array(a);
+  window.crypto.getRandomValues(rnd);  // Yay!
+  for (var i = 0; i < a; ++i) tmp[i] = rnd[i] & 255;
+  return tmp;
+}
+
+function UTIL_setFavicon(icon) {
+  // Construct a new favion link tag
+  var faviconLink = document.createElement('link');
+  faviconLink.rel = 'Shortcut Icon';
+  faviconLink.type = 'image/x-icon';
+  faviconLink.href = icon;
+
+  // Remove the old favion, if it exists
+  var head = document.getElementsByTagName('head')[0];
+  var links = head.getElementsByTagName('link');
+  for (var i = 0; i < links.length; i++) {
+    var link = links[i];
+    if (link.type == faviconLink.type && link.rel == faviconLink.rel) {
+      head.removeChild(link);
+    }
+  }
+
+  // Add in the new one
+  head.appendChild(faviconLink);
+}
+
+// Erase all entries in array
+function UTIL_clear(a) {
+  if (a instanceof Array) {
+    for (var i = 0; i < a.length; ++i)
+      a[i] = 0;
+  }
+}
+
+// hr:min:sec.milli string
+function UTIL_time() {
+  var d = new Date();
+  var m = '000' + d.getMilliseconds();
+  var s = d.toTimeString().substring(0, 8) + '.' + m.substring(m.length - 3);
+  return s;
+}
+var UTIL_events = [];
+var UTIL_max_events = 500;
+
+function UTIL_fmt(s) {
+  var line = UTIL_time() + ' ' + s;
+  if (UTIL_events.push(line) > UTIL_max_events) {
+    // Drop from head.
+    UTIL_events.splice(0, UTIL_events.length - UTIL_max_events);
+  }
+  return line;
+}