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+/*
+ * This file is part of Privacy Badger <https://www.eff.org/privacybadger>
+ * Copyright (C) 2014 Electronic Frontier Foundation
+ *
+ * Derived from Adblock Plus
+ * Copyright (C) 2006-2013 Eyeo GmbH
+ *
+ * Privacy Badger is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 as
+ * published by the Free Software Foundation.
+ *
+ * Privacy Badger is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Privacy Badger.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/* globals URI:false */
+
+require.scopes.utils = (function() {
+
+let mdfp = require("multiDomainFP");
+
+/**
+ * Generic interface to make an XHR request
+ *
+ * @param {String} url The url to get
+ * @param {Function} callback The callback to call after request has finished
+ * @param {String} method GET/POST
+ * @param {Object} opts XMLHttpRequest options
+ */
+function xhrRequest(url, callback, method, opts) {
+  if (!method) {
+    method = "GET";
+  }
+  if (!opts) {
+    opts = {};
+  }
+
+  let xhr = new XMLHttpRequest();
+
+  for (let key in opts) {
+    if (opts.hasOwnProperty(key)) {
+      xhr[key] = opts[key];
+    }
+  }
+
+  xhr.onload = function () {
+    if (xhr.status == 200) {
+      callback(null, xhr.response);
+    } else {
+      let error = {
+        status: xhr.status,
+        message: xhr.response,
+        object: xhr
+      };
+      callback(error, error.message);
+    }
+  };
+
+  // triggered by network problems
+  xhr.onerror = function () {
+    callback({ status: 0, message: "", object: xhr }, "");
+  };
+
+  xhr.open(method, url, true);
+  xhr.send();
+}
+
+/**
+ * Converts binary data to base64-encoded text suitable for use in data URIs.
+ *
+ * Adapted from https://stackoverflow.com/a/9458996.
+ *
+ * @param {ArrayBuffer} buffer binary data
+ *
+ * @returns {String} base64-encoded text
+ */
+function arrayBufferToBase64(buffer) {
+  var binary = '';
+  var bytes = new Uint8Array(buffer);
+  var len = bytes.byteLength;
+  for (var i = 0; i < len; i++) {
+    binary += String.fromCharCode(bytes[i]);
+  }
+  return btoa(binary);
+}
+
+/**
+ * Return an array of all subdomains in an FQDN, ordered from the FQDN to the
+ * eTLD+1. e.g. [a.b.eff.org, b.eff.org, eff.org]
+ * if 'all' is passed in then the array will include all domain levels, not
+ * just down to the base domain
+ * @param {String} fqdn the domain to split
+ * @param {boolean} all whether to include all domain levels
+ * @returns {Array} the subdomains
+ */
+function explodeSubdomains(fqdn, all) {
+  var baseDomain;
+  if (all) {
+    baseDomain = fqdn.split('.').pop();
+  } else {
+    baseDomain = window.getBaseDomain(fqdn);
+  }
+  var baseLen = baseDomain.split('.').length;
+  var parts = fqdn.split('.');
+  var numLoops = parts.length - baseLen;
+  var subdomains = [];
+  for (var i=0; i<=numLoops; i++) {
+    subdomains.push(parts.slice(i).join('.'));
+  }
+  return subdomains;
+}
+
+/*
+ * Estimates the max possible entropy of string.
+ *
+ * @param {String} str the string to compute entropy for
+ * @returns {Integer} bits of entropy
+ */
+function estimateMaxEntropy(str) {
+  // Don't process strings longer than MAX_LS_LEN_FOR_ENTROPY_EST.
+  // Note that default quota for local storage is 5MB and
+  // storing fonts, scripts or images in for local storage for
+  // performance is not uncommon. We wouldn't want to estimate entropy
+  // for 5M chars.
+  const MAX_LS_LEN_FOR_ENTROPY_EST = 256;
+
+  // common classes of characters that a string might belong to
+  const SEPS = "._-x";
+  const BIN = "01";
+  const DEC = "0123456789";
+
+  // these classes are case-insensitive
+  const HEX = "abcdef" + DEC;
+  const ALPHA = "abcdefghijklmnopqrstuvwxyz";
+  const ALPHANUM = ALPHA + DEC;
+
+  // these classes are case-sensitive
+  const B64 = ALPHANUM + ALPHA.toUpperCase() + "/+";
+  const URL = ALPHANUM + ALPHA.toUpperCase() + "~%";
+
+  if (str.length > MAX_LS_LEN_FOR_ENTROPY_EST) {
+    // Just return a higher-than-threshold entropy estimate.
+    // We assume 1 bit per char, which will be well over the
+    // threshold (33 bits).
+    return str.length;
+  }
+
+  let max_symbols;
+
+  // If all characters are upper or lower case, don't consider case when
+  // computing entropy.
+  let sameCase = (str.toLowerCase() == str) || (str.toUpperCase() == str);
+  if (sameCase) {
+    str = str.toLowerCase();
+  }
+
+  // If all the characters come from one of these common character groups,
+  // assume that the group is the domain of possible characters.
+  for (let chr_class of [BIN, DEC, HEX, ALPHA, ALPHANUM, B64, URL]) {
+    let group = chr_class + SEPS;
+    // Ignore separator characters when computing entropy. For example, Google
+    // Analytics IDs look like "14103492.1964907".
+
+    // flag to check if each character of input string belongs to the group in question
+    let each_char_in_group = true;
+
+    for (let ch of str) {
+      if (!group.includes(ch)) {
+        each_char_in_group = false;
+        break;
+      }
+    }
+
+    // if the flag resolves to true, we've found our culprit and can break out of the loop
+    if (each_char_in_group) {
+      max_symbols = chr_class.length;
+      break;
+    }
+  }
+
+  // If there's not an obvious class of characters, use the heuristic
+  // "max char code - min char code"
+  if (!max_symbols) {
+    let charCodes = Array.prototype.map.call(str, function (ch) {
+      return String.prototype.charCodeAt.apply(ch);
+    });
+    let min_char_code = Math.min.apply(Math, charCodes);
+    let max_char_code = Math.max.apply(Math, charCodes);
+    max_symbols = max_char_code - min_char_code + 1;
+  }
+
+  // the entropy is (entropy per character) * (number of characters)
+  let max_bits = (Math.log(max_symbols) / Math.LN2) * str.length;
+
+  return max_bits;
+}
+
+function oneSecond() {
+  return 1000;
+}
+
+function oneMinute() {
+  return oneSecond() * 60;
+}
+
+function oneHour() {
+  return oneMinute() * 60;
+}
+
+function oneDay() {
+  return oneHour() * 24;
+}
+
+function nDaysFromNow(n) {
+  return Date.now() + (oneDay() * n);
+}
+
+function oneDayFromNow() {
+  return nDaysFromNow(1);
+}
+
+/**
+ * Creates a rate-limited function that delays invoking `fn` until after
+ * `interval` milliseconds have elapsed since the last time the rate-limited
+ * function was invoked.
+ *
+ * Does not drop invocations (lossless), unlike `_.throttle`.
+ *
+ * Adapted from
+ * http://stackoverflow.com/questions/23072815/throttle-javascript-function-calls-but-with-queuing-dont-discard-calls
+ *
+ * @param {Function} fn The function to rate-limit.
+ * @param {number} interval The number of milliseconds to rate-limit invocations to.
+ * @param {Object} context The context object (optional).
+ * @returns {Function} Returns the new rate-limited function.
+ */
+function rateLimit(fn, interval, context) {
+  let canInvoke = true,
+    queue = [],
+    timer_id,
+    limited = function () {
+      queue.push({
+        context: context || this,
+        arguments: Array.prototype.slice.call(arguments)
+      });
+      if (canInvoke) {
+        canInvoke = false;
+        timeEnd();
+      }
+    };
+
+  function timeEnd() {
+    let item;
+    if (queue.length) {
+      item = queue.splice(0, 1)[0];
+      fn.apply(item.context, item.arguments); // invoke fn
+      timer_id = window.setTimeout(timeEnd, interval);
+    } else {
+      canInvoke = true;
+    }
+  }
+
+  // useful for debugging
+  limited.cancel = function () {
+    window.clearTimeout(timer_id);
+    queue = [];
+    canInvoke = true;
+  };
+
+  return limited;
+}
+
+function buf2hex(buffer) { // buffer is an ArrayBuffer
+  return Array.prototype.map.call(new Uint8Array(buffer), x => ('00' + x.toString(16)).slice(-2)).join('');
+}
+
+function sha1(input, callback) {
+  return window.crypto.subtle.digest(
+    { name: "SHA-1", },
+    new TextEncoder().encode(input)
+  ).then(hashed => {
+    return callback(buf2hex(hashed));
+  });
+}
+
+function parseCookie(str, opts) {
+  if (!str) {
+    return {};
+  }
+
+  opts = opts || {};
+
+  let COOKIE_ATTRIBUTES = [
+    "domain",
+    "expires",
+    "httponly",
+    "max-age",
+    "path",
+    "samesite",
+    "secure",
+  ];
+
+  let parsed = {},
+    cookies = str.replace(/\n/g, ";").split(";");
+
+  for (let i = 0; i < cookies.length; i++) {
+    let cookie = cookies[i],
+      name,
+      value,
+      cut = cookie.indexOf("=");
+
+    // it's a key=value pair
+    if (cut != -1) {
+      name = cookie.slice(0, cut).trim();
+      value = cookie.slice(cut + 1).trim();
+
+      // handle value quoting
+      if (value[0] == '"') {
+        value = value.slice(1, -1);
+      }
+
+    // not a key=value pair
+    } else {
+      if (opts.skipNonValues) {
+        continue;
+      }
+      name = cookie.trim();
+      value = "";
+    }
+
+    if (opts.skipAttributes &&
+        COOKIE_ATTRIBUTES.indexOf(name.toLowerCase()) != -1) {
+      continue;
+    }
+
+    if (!opts.noDecode) {
+      let decode = opts.decode || decodeURIComponent;
+      try {
+        name = decode(name);
+      } catch (e) {
+        // invalid URL encoding probably (URIError: URI malformed)
+        if (opts.skipInvalid) {
+          continue;
+        }
+      }
+      if (value) {
+        try {
+          value = decode(value);
+        } catch (e) {
+          // ditto
+          if (opts.skipInvalid) {
+            continue;
+          }
+        }
+      }
+    }
+
+    if (!opts.noOverwrite || !parsed.hasOwnProperty(name)) {
+      parsed[name] = value;
+    }
+  }
+
+  return parsed;
+}
+
+function getHostFromDomainInput(input) {
+  if (!input.startsWith("http")) {
+    input = "http://" + input;
+  }
+
+  if (!input.endsWith("/")) {
+    input += "/";
+  }
+
+  try {
+    var uri = new URI(input);
+  } catch (err) {
+    return false;
+  }
+
+  return uri.host;
+}
+
+/**
+ * check if a domain is third party
+ * @param {String} domain1 an fqdn
+ * @param {String} domain2 a second fqdn
+ *
+ * @return {Boolean} true if the domains are third party
+ */
+function isThirdPartyDomain(domain1, domain2) {
+  if (window.isThirdParty(domain1, domain2)) {
+    return !mdfp.isMultiDomainFirstParty(
+      window.getBaseDomain(domain1),
+      window.getBaseDomain(domain2)
+    );
+  }
+  return false;
+}
+
+
+/**
+ * Checks whether a given URL is a special browser page.
+ * TODO account for browser-specific pages:
+ * https://github.com/hackademix/noscript/blob/a8b35486571933043bb62e90076436dff2a34cd2/src/lib/restricted.js
+ *
+ * @param {String} url
+ *
+ * @return {Boolean} whether the URL is restricted
+ */
+function isRestrictedUrl(url) {
+  // permitted schemes from
+  // https://developer.chrome.com/extensions/match_patterns
+  return !(
+    url.startsWith('http') || url.startsWith('file') || url.startsWith('ftp')
+  );
+}
+
+/************************************** exports */
+let exports = {
+  arrayBufferToBase64,
+  estimateMaxEntropy,
+  explodeSubdomains,
+  getHostFromDomainInput,
+  isRestrictedUrl,
+  isThirdPartyDomain,
+  nDaysFromNow,
+  oneDay,
+  oneDayFromNow,
+  oneHour,
+  oneMinute,
+  oneSecond,
+  parseCookie,
+  rateLimit,
+  sha1,
+  xhrRequest,
+};
+return exports;
+/************************************** exports */
+})(); //require scopes