Add Basilisk

1 files changed, 887 insertions, 0 deletions

diff --git a/application/basilisk/base/content/sanitize.js b/application/basilisk/base/content/sanitize.js
new file mode 100644
index 000000000..e7276f8da
--- /dev/null
+++ b/application/basilisk/base/content/sanitize.js
@@ -0,0 +1,887 @@
+// -*- indent-tabs-mode: nil; js-indent-level: 2 -*-
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+Components.utils.import("resource://gre/modules/XPCOMUtils.jsm");
+Components.utils.import("resource://gre/modules/Services.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "PlacesUtils",
+                                  "resource://gre/modules/PlacesUtils.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "FormHistory",
+                                  "resource://gre/modules/FormHistory.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "Downloads",
+                                  "resource://gre/modules/Downloads.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "Promise",
+                                  "resource://gre/modules/Promise.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "Task",
+                                  "resource://gre/modules/Task.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "DownloadsCommon",
+                                  "resource:///modules/DownloadsCommon.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "TelemetryStopwatch",
+                                  "resource://gre/modules/TelemetryStopwatch.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "console",
+                                  "resource://gre/modules/Console.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "Preferences",
+                                  "resource://gre/modules/Preferences.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "setTimeout",
+                                  "resource://gre/modules/Timer.jsm");
+
+/**
+ * A number of iterations after which to yield time back
+ * to the system.
+ */
+const YIELD_PERIOD = 10;
+
+function Sanitizer() {
+}
+Sanitizer.prototype = {
+  // warning to the caller: this one may raise an exception (e.g. bug #265028)
+  clearItem(aItemName) {
+    this.items[aItemName].clear();
+  },
+
+  prefDomain: "",
+  isShutDown: false,
+
+  getNameFromPreference(aPreferenceName) {
+    return aPreferenceName.substr(this.prefDomain.length);
+  },
+
+  /**
+   * Deletes privacy sensitive data in a batch, according to user preferences.
+   * Returns a promise which is resolved if no errors occurred.  If an error
+   * occurs, a message is reported to the console and all other items are still
+   * cleared before the promise is finally rejected.
+   *
+   * @param [optional] itemsToClear
+   *        Array of items to be cleared. if specified only those
+   *        items get cleared, irrespectively of the preference settings.
+   * @param [optional] options
+   *        Object whose properties are options for this sanitization.
+   *        TODO (bug 1167238) document options here.
+   */
+  sanitize: Task.async(function*(itemsToClear = null, options = {}) {
+    let progress = options.progress || {};
+    let promise = this._sanitize(itemsToClear, progress);
+
+    // Depending on preferences, the sanitizer may perform asynchronous
+    // work before it starts cleaning up the Places database (e.g. closing
+    // windows). We need to make sure that the connection to that database
+    // hasn't been closed by the time we use it.
+    // Though, if this is a sanitize on shutdown, we already have a blocker.
+    if (!progress.isShutdown) {
+      let shutdownClient = Cc["@mozilla.org/browser/nav-history-service;1"]
+                             .getService(Ci.nsPIPlacesDatabase)
+                             .shutdownClient
+                             .jsclient;
+      shutdownClient.addBlocker("sanitize.js: Sanitize",
+        promise,
+        {
+          fetchState: () => ({ progress })
+        }
+      );
+    }
+
+    try {
+      yield promise;
+    } finally {
+      Services.obs.notifyObservers(null, "sanitizer-sanitization-complete", "");
+    }
+  }),
+
+  _sanitize: Task.async(function*(aItemsToClear, progress = {}) {
+    let seenError = false;
+    let itemsToClear;
+    if (Array.isArray(aItemsToClear)) {
+      // Shallow copy the array, as we are going to modify
+      // it in place later.
+      itemsToClear = [...aItemsToClear];
+    } else {
+      let branch = Services.prefs.getBranch(this.prefDomain);
+      itemsToClear = Object.keys(this.items).filter(itemName => {
+        try {
+          return branch.getBoolPref(itemName);
+        } catch (ex) {
+          return false;
+        }
+      });
+    }
+
+    // Store the list of items to clear, in case we are killed before we
+    // get a chance to complete.
+    Preferences.set(Sanitizer.PREF_SANITIZE_IN_PROGRESS,
+                    JSON.stringify(itemsToClear));
+
+    // Store the list of items to clear, for debugging/forensics purposes
+    for (let k of itemsToClear) {
+      progress[k] = "ready";
+    }
+
+    // Ensure open windows get cleared first, if they're in our list, so that they don't stick
+    // around in the recently closed windows list, and so we can cancel the whole thing
+    // if the user selects to keep a window open from a beforeunload prompt.
+    let openWindowsIndex = itemsToClear.indexOf("openWindows");
+    if (openWindowsIndex != -1) {
+      itemsToClear.splice(openWindowsIndex, 1);
+      yield this.items.openWindows.clear();
+      progress.openWindows = "cleared";
+    }
+
+    // Cache the range of times to clear
+    let range = null;
+    // If we ignore timespan, clear everything,
+    // otherwise, pick a range.
+    if (!this.ignoreTimespan) {
+      range = this.range || Sanitizer.getClearRange();
+    }
+
+    // For performance reasons we start all the clear tasks at once, then wait
+    // for their promises later.
+    // Some of the clear() calls may raise exceptions (for example bug 265028),
+    // we catch and store them, but continue to sanitize as much as possible.
+    // Callers should check returned errors and give user feedback
+    // about items that could not be sanitized
+    let refObj = {};
+    TelemetryStopwatch.start("FX_SANITIZE_TOTAL", refObj);
+
+    let annotateError = (name, ex) => {
+      progress[name] = "failed";
+      seenError = true;
+      console.error("Error sanitizing " + name, ex);
+    };
+
+    // Array of objects in form { name, promise }.
+    // `name` is the item's name and `promise` may be a promise, if the
+    // sanitization is asynchronous, or the function return value, otherwise.
+    let handles = [];
+    for (let name of itemsToClear) {
+      let item = this.items[name];
+      item.isShutdown = this.isShutdown;
+      try {
+        // Catch errors here, so later we can just loop through these.
+        handles.push({ name,
+                       promise: item.clear(range)
+                                    .then(() => progress[name] = "cleared",
+                                          ex => annotateError(name, ex))
+                     });
+      } catch (ex) {
+        annotateError(name, ex);
+      }
+    }
+    for (let handle of handles) {
+      progress[handle.name] = "blocking";
+      yield handle.promise;
+    }
+
+    // Sanitization is complete.
+    TelemetryStopwatch.finish("FX_SANITIZE_TOTAL", refObj);
+    // Reset the inProgress preference since we were not killed during
+    // sanitization.
+    Preferences.reset(Sanitizer.PREF_SANITIZE_IN_PROGRESS);
+    progress = {};
+    if (seenError) {
+      throw new Error("Error sanitizing");
+    }
+  }),
+
+  // Time span only makes sense in certain cases.  Consumers who want
+  // to only clear some private data can opt in by setting this to false,
+  // and can optionally specify a specific range.  If timespan is not ignored,
+  // and range is not set, sanitize() will use the value of the timespan
+  // pref to determine a range
+  ignoreTimespan : true,
+  range : null,
+
+  items: {
+    cache: {
+      clear: Task.async(function* (range) {
+        let seenException;
+        let refObj = {};
+        TelemetryStopwatch.start("FX_SANITIZE_CACHE", refObj);
+
+        try {
+          // Cache doesn't consult timespan, nor does it have the
+          // facility for timespan-based eviction.  Wipe it.
+          let cache = Cc["@mozilla.org/netwerk/cache-storage-service;1"]
+                        .getService(Ci.nsICacheStorageService);
+          cache.clear();
+        } catch (ex) {
+          seenException = ex;
+        }
+
+        try {
+          let imageCache = Cc["@mozilla.org/image/tools;1"]
+                             .getService(Ci.imgITools)
+                             .getImgCacheForDocument(null);
+          imageCache.clearCache(false); // true=chrome, false=content
+        } catch (ex) {
+          seenException = ex;
+        }
+
+        TelemetryStopwatch.finish("FX_SANITIZE_CACHE", refObj);
+        if (seenException) {
+          throw seenException;
+        }
+      })
+    },
+
+    cookies: {
+      clear: Task.async(function* (range) {
+        let seenException;
+        let yieldCounter = 0;
+        let refObj = {};
+
+        // Clear cookies.
+        TelemetryStopwatch.start("FX_SANITIZE_COOKIES_2", refObj);
+        try {
+          let cookieMgr = Components.classes["@mozilla.org/cookiemanager;1"]
+                                    .getService(Ci.nsICookieManager);
+          if (range) {
+            // Iterate through the cookies and delete any created after our cutoff.
+            let cookiesEnum = cookieMgr.enumerator;
+            while (cookiesEnum.hasMoreElements()) {
+              let cookie = cookiesEnum.getNext().QueryInterface(Ci.nsICookie2);
+
+              if (cookie.creationTime > range[0]) {
+                // This cookie was created after our cutoff, clear it
+                cookieMgr.remove(cookie.host, cookie.name, cookie.path,
+                                 false, cookie.originAttributes);
+
+                if (++yieldCounter % YIELD_PERIOD == 0) {
+                  yield new Promise(resolve => setTimeout(resolve, 0)); // Don't block the main thread too long
+                }
+              }
+            }
+          } else {
+            // Remove everything
+            cookieMgr.removeAll();
+            yield new Promise(resolve => setTimeout(resolve, 0)); // Don't block the main thread too long
+          }
+        } catch (ex) {
+          seenException = ex;
+        } finally {
+          TelemetryStopwatch.finish("FX_SANITIZE_COOKIES_2", refObj);
+        }
+
+        // Clear deviceIds. Done asynchronously (returns before complete).
+        try {
+          let mediaMgr = Components.classes["@mozilla.org/mediaManagerService;1"]
+                                   .getService(Ci.nsIMediaManagerService);
+          mediaMgr.sanitizeDeviceIds(range && range[0]);
+        } catch (ex) {
+          seenException = ex;
+        }
+
+        // Clear plugin data.
+        try {
+          yield Sanitizer.clearPluginData(range);
+        } catch (ex) {
+          seenException = ex;
+        }
+
+        if (seenException) {
+          throw seenException;
+        }
+      }),
+    },
+
+    offlineApps: {
+      clear: Task.async(function* (range) {
+        Components.utils.import("resource:///modules/offlineAppCache.jsm");
+        // This doesn't wait for the cleanup to be complete.
+        OfflineAppCacheHelper.clear();
+        if (!range || this.isShutDown) {
+          // Clear local storage entries
+          Components.utils.import("resource:///modules/QuotaManager.jsm");
+          QuotaManagerHelper.clear(this.isShutdown);
+        }
+      })
+    },
+
+    history: {
+      clear: Task.async(function* (range) {
+        let seenException;
+        let refObj = {};
+        TelemetryStopwatch.start("FX_SANITIZE_HISTORY", refObj);
+        try {
+          if (range) {
+            yield PlacesUtils.history.removeVisitsByFilter({
+              beginDate: new Date(range[0] / 1000),
+              endDate: new Date(range[1] / 1000)
+            });
+          } else {
+            // Remove everything.
+            yield PlacesUtils.history.clear();
+          }
+        } catch (ex) {
+          seenException = ex;
+        } finally {
+          TelemetryStopwatch.finish("FX_SANITIZE_HISTORY", refObj);
+        }
+
+        try {
+          let clearStartingTime = range ? String(range[0]) : "";
+          Services.obs.notifyObservers(null, "browser:purge-session-history", clearStartingTime);
+        } catch (ex) {
+          seenException = ex;
+        }
+
+        try {
+          let predictor = Components.classes["@mozilla.org/network/predictor;1"]
+                                    .getService(Components.interfaces.nsINetworkPredictor);
+          predictor.reset();
+        } catch (ex) {
+          seenException = ex;
+        }
+
+        if (seenException) {
+          throw seenException;
+        }
+      })
+    },
+
+    formdata: {
+      clear: Task.async(function* (range) {
+        let seenException;
+        let refObj = {};
+        TelemetryStopwatch.start("FX_SANITIZE_FORMDATA", refObj);
+        try {
+          // Clear undo history of all search bars.
+          let windows = Services.wm.getEnumerator("navigator:browser");
+          while (windows.hasMoreElements()) {
+            let currentWindow = windows.getNext();
+            let currentDocument = currentWindow.document;
+
+            // searchBar.textbox may not exist due to the search bar binding
+            // not having been constructed yet if the search bar is in the
+            // overflow or menu panel. It won't have a value or edit history in
+            // that case.
+            let searchBar = currentDocument.getElementById("searchbar");
+            if (searchBar && searchBar.textbox)
+              searchBar.textbox.reset();
+
+            let tabBrowser = currentWindow.gBrowser;
+            if (!tabBrowser) {
+              // No tab browser? This means that it's too early during startup (typically,
+              // Session Restore hasn't completed yet). Since we don't have find
+              // bars at that stage and since Session Restore will not restore
+              // find bars further down during startup, we have nothing to clear.
+              continue;
+            }
+            for (let tab of tabBrowser.tabs) {
+              if (tabBrowser.isFindBarInitialized(tab))
+                tabBrowser.getFindBar(tab).clear();
+            }
+            // Clear any saved find value
+            tabBrowser._lastFindValue = "";
+          }
+        } catch (ex) {
+          seenException = ex;
+        }
+
+        try {
+          let change = { op: "remove" };
+          if (range) {
+            [ change.firstUsedStart, change.firstUsedEnd ] = range;
+          }
+          yield new Promise(resolve => {
+            FormHistory.update(change, {
+              handleError(e) {
+                seenException = new Error("Error " + e.result + ": " + e.message);
+              },
+              handleCompletion() {
+                resolve();
+              }
+            });
+          });
+        } catch (ex) {
+          seenException = ex;
+        }
+
+        TelemetryStopwatch.finish("FX_SANITIZE_FORMDATA", refObj);
+        if (seenException) {
+          throw seenException;
+        }
+      })
+    },
+
+    downloads: {
+      clear: Task.async(function* (range) {
+        let refObj = {};
+        TelemetryStopwatch.start("FX_SANITIZE_DOWNLOADS", refObj);
+        try {
+          let filterByTime = null;
+          if (range) {
+            // Convert microseconds back to milliseconds for date comparisons.
+            let rangeBeginMs = range[0] / 1000;
+            let rangeEndMs = range[1] / 1000;
+            filterByTime = download => download.startTime >= rangeBeginMs &&
+                                       download.startTime <= rangeEndMs;
+          }
+
+          // Clear all completed/cancelled downloads
+          let list = yield Downloads.getList(Downloads.ALL);
+          list.removeFinished(filterByTime);
+        } finally {
+          TelemetryStopwatch.finish("FX_SANITIZE_DOWNLOADS", refObj);
+        }
+      })
+    },
+
+    sessions: {
+      clear: Task.async(function* (range) {
+        let refObj = {};
+        TelemetryStopwatch.start("FX_SANITIZE_SESSIONS", refObj);
+
+        try {
+          // clear all auth tokens
+          let sdr = Components.classes["@mozilla.org/security/sdr;1"]
+                              .getService(Components.interfaces.nsISecretDecoderRing);
+          sdr.logoutAndTeardown();
+
+          // clear FTP and plain HTTP auth sessions
+          Services.obs.notifyObservers(null, "net:clear-active-logins", null);
+        } finally {
+          TelemetryStopwatch.finish("FX_SANITIZE_SESSIONS", refObj);
+        }
+      })
+    },
+
+    siteSettings: {
+      clear: Task.async(function* (range) {
+        let seenException;
+        let refObj = {};
+        TelemetryStopwatch.start("FX_SANITIZE_SITESETTINGS", refObj);
+
+        let startDateMS = range ? range[0] / 1000 : null;
+
+        try {
+          // Clear site-specific permissions like "Allow this site to open popups"
+          // we ignore the "end" range and hope it is now() - none of the
+          // interfaces used here support a true range anyway.
+          if (startDateMS == null) {
+            Services.perms.removeAll();
+          } else {
+            Services.perms.removeAllSince(startDateMS);
+          }
+        } catch (ex) {
+          seenException = ex;
+        }
+
+        try {
+          // Clear site-specific settings like page-zoom level
+          let cps = Components.classes["@mozilla.org/content-pref/service;1"]
+                              .getService(Components.interfaces.nsIContentPrefService2);
+          if (startDateMS == null) {
+            cps.removeAllDomains(null);
+          } else {
+            cps.removeAllDomainsSince(startDateMS, null);
+          }
+        } catch (ex) {
+          seenException = ex;
+        }
+
+        try {
+          // Clear site security settings - no support for ranges in this
+          // interface either, so we clearAll().
+          let sss = Cc["@mozilla.org/ssservice;1"]
+                      .getService(Ci.nsISiteSecurityService);
+          sss.clearAll();
+        } catch (ex) {
+          seenException = ex;
+        }
+
+        // Clear all push notification subscriptions
+        try {
+          yield new Promise((resolve, reject) => {
+            let push = Cc["@mozilla.org/push/Service;1"]
+                         .getService(Ci.nsIPushService);
+            push.clearForDomain("*", status => {
+              if (Components.isSuccessCode(status)) {
+                resolve();
+              } else {
+                reject(new Error("Error clearing push subscriptions: " +
+                                 status));
+              }
+            });
+          });
+        } catch (ex) {
+          seenException = ex;
+        }
+
+        TelemetryStopwatch.finish("FX_SANITIZE_SITESETTINGS", refObj);
+        if (seenException) {
+          throw seenException;
+        }
+      })
+    },
+
+    openWindows: {
+      privateStateForNewWindow: "non-private",
+      _canCloseWindow(aWindow) {
+        if (aWindow.CanCloseWindow()) {
+          // We already showed PermitUnload for the window, so let's
+          // make sure we don't do it again when we actually close the
+          // window.
+          aWindow.skipNextCanClose = true;
+          return true;
+        }
+        return false;
+      },
+      _resetAllWindowClosures(aWindowList) {
+        for (let win of aWindowList) {
+          win.skipNextCanClose = false;
+        }
+      },
+      clear: Task.async(function* () {
+        // NB: this closes all *browser* windows, not other windows like the library, about window,
+        // browser console, etc.
+
+        // Keep track of the time in case we get stuck in la-la-land because of onbeforeunload
+        // dialogs
+        let existingWindow = Services.appShell.hiddenDOMWindow;
+        let startDate = existingWindow.performance.now();
+
+        // First check if all these windows are OK with being closed:
+        let windowEnumerator = Services.wm.getEnumerator("navigator:browser");
+        let windowList = [];
+        while (windowEnumerator.hasMoreElements()) {
+          let someWin = windowEnumerator.getNext();
+          windowList.push(someWin);
+          // If someone says "no" to a beforeunload prompt, we abort here:
+          if (!this._canCloseWindow(someWin)) {
+            this._resetAllWindowClosures(windowList);
+            throw new Error("Sanitize could not close windows: cancelled by user");
+          }
+
+          // ...however, beforeunload prompts spin the event loop, and so the code here won't get
+          // hit until the prompt has been dismissed. If more than 1 minute has elapsed since we
+          // started prompting, stop, because the user might not even remember initiating the
+          // 'forget', and the timespans will be all wrong by now anyway:
+          if (existingWindow.performance.now() > (startDate + 60 * 1000)) {
+            this._resetAllWindowClosures(windowList);
+            throw new Error("Sanitize could not close windows: timeout");
+          }
+        }
+
+        // If/once we get here, we should actually be able to close all windows.
+
+        let refObj = {};
+        TelemetryStopwatch.start("FX_SANITIZE_OPENWINDOWS", refObj);
+
+        // First create a new window. We do this first so that on non-mac, we don't
+        // accidentally close the app by closing all the windows.
+        let handler = Cc["@mozilla.org/browser/clh;1"].getService(Ci.nsIBrowserHandler);
+        let defaultArgs = handler.defaultArgs;
+        let features = "chrome,all,dialog=no," + this.privateStateForNewWindow;
+        let newWindow = existingWindow.openDialog("chrome://browser/content/", "_blank",
+                                                  features, defaultArgs);
+
+        let onFullScreen = null;
+#ifdef XP_MACOSX
+        onFullScreen = function(e) {
+          newWindow.removeEventListener("fullscreen", onFullScreen);
+          let docEl = newWindow.document.documentElement;
+          let sizemode = docEl.getAttribute("sizemode");
+          if (!newWindow.fullScreen && sizemode == "fullscreen") {
+            docEl.setAttribute("sizemode", "normal");
+            e.preventDefault();
+            e.stopPropagation();
+            return false;
+          }
+          return undefined;
+        }
+        newWindow.addEventListener("fullscreen", onFullScreen);
+#endif
+
+        let promiseReady = new Promise(resolve => {
+          // Window creation and destruction is asynchronous. We need to wait
+          // until all existing windows are fully closed, and the new window is
+          // fully open, before continuing. Otherwise the rest of the sanitizer
+          // could run too early (and miss new cookies being set when a page
+          // closes) and/or run too late (and not have a fully-formed window yet
+          // in existence). See bug 1088137.
+          let newWindowOpened = false;
+          let onWindowOpened = function(subject, topic, data) {
+            if (subject != newWindow)
+              return;
+
+            Services.obs.removeObserver(onWindowOpened, "browser-delayed-startup-finished");
+#ifdef XP_MACOSX
+            newWindow.removeEventListener("fullscreen", onFullScreen);
+#endif
+            newWindowOpened = true;
+            // If we're the last thing to happen, invoke callback.
+            if (numWindowsClosing == 0) {
+              TelemetryStopwatch.finish("FX_SANITIZE_OPENWINDOWS", refObj);
+              resolve();
+            }
+          }
+
+          let numWindowsClosing = windowList.length;
+          let onWindowClosed = function() {
+            numWindowsClosing--;
+            if (numWindowsClosing == 0) {
+              Services.obs.removeObserver(onWindowClosed, "xul-window-destroyed");
+              // If we're the last thing to happen, invoke callback.
+              if (newWindowOpened) {
+                TelemetryStopwatch.finish("FX_SANITIZE_OPENWINDOWS", refObj);
+                resolve();
+              }
+            }
+          }
+          Services.obs.addObserver(onWindowOpened, "browser-delayed-startup-finished", false);
+          Services.obs.addObserver(onWindowClosed, "xul-window-destroyed", false);
+        });
+
+        // Start the process of closing windows
+        while (windowList.length) {
+          windowList.pop().close();
+        }
+        newWindow.focus();
+        yield promiseReady;
+      })
+    },
+
+    pluginData: {
+      clear: Task.async(function* (range) {
+        yield Sanitizer.clearPluginData(range);
+      }),
+    },
+  }
+};
+
+// The preferences branch for the sanitizer.
+Sanitizer.PREF_DOMAIN = "privacy.sanitize.";
+// Whether we should sanitize on shutdown.
+Sanitizer.PREF_SANITIZE_ON_SHUTDOWN = "privacy.sanitize.sanitizeOnShutdown";
+// During a sanitization this is set to a json containing the array of items
+// being sanitized, then cleared once the sanitization is complete.
+// This allows to retry a sanitization on startup in case it was interrupted
+// by a crash.
+Sanitizer.PREF_SANITIZE_IN_PROGRESS = "privacy.sanitize.sanitizeInProgress";
+// Whether the previous shutdown sanitization completed successfully.
+// This is used to detect cases where we were supposed to sanitize on shutdown
+// but due to a crash we were unable to.  In such cases there may not be any
+// sanitization in progress, cause we didn't have a chance to start it yet.
+Sanitizer.PREF_SANITIZE_DID_SHUTDOWN = "privacy.sanitize.didShutdownSanitize";
+
+// Time span constants corresponding to values of the privacy.sanitize.timeSpan
+// pref.  Used to determine how much history to clear, for various items
+Sanitizer.TIMESPAN_EVERYTHING = 0;
+Sanitizer.TIMESPAN_HOUR       = 1;
+Sanitizer.TIMESPAN_2HOURS     = 2;
+Sanitizer.TIMESPAN_4HOURS     = 3;
+Sanitizer.TIMESPAN_TODAY      = 4;
+Sanitizer.TIMESPAN_5MIN       = 5;
+Sanitizer.TIMESPAN_24HOURS    = 6;
+
+// Return a 2 element array representing the start and end times,
+// in the uSec-since-epoch format that PRTime likes.  If we should
+// clear everything, return null.  Use ts if it is defined; otherwise
+// use the timeSpan pref.
+Sanitizer.getClearRange = function(ts) {
+  if (ts === undefined)
+    ts = Sanitizer.prefs.getIntPref("timeSpan");
+  if (ts === Sanitizer.TIMESPAN_EVERYTHING)
+    return null;
+
+  // PRTime is microseconds while JS time is milliseconds
+  var endDate = Date.now() * 1000;
+  switch (ts) {
+    case Sanitizer.TIMESPAN_5MIN :
+      var startDate = endDate - 300000000; // 5*60*1000000
+      break;
+    case Sanitizer.TIMESPAN_HOUR :
+      startDate = endDate - 3600000000; // 1*60*60*1000000
+      break;
+    case Sanitizer.TIMESPAN_2HOURS :
+      startDate = endDate - 7200000000; // 2*60*60*1000000
+      break;
+    case Sanitizer.TIMESPAN_4HOURS :
+      startDate = endDate - 14400000000; // 4*60*60*1000000
+      break;
+    case Sanitizer.TIMESPAN_TODAY :
+      var d = new Date();  // Start with today
+      d.setHours(0);      // zero us back to midnight...
+      d.setMinutes(0);
+      d.setSeconds(0);
+      startDate = d.valueOf() * 1000; // convert to epoch usec
+      break;
+    case Sanitizer.TIMESPAN_24HOURS :
+      startDate = endDate - 86400000000; // 24*60*60*1000000
+      break;
+    default:
+      throw "Invalid time span for clear private data: " + ts;
+  }
+  return [startDate, endDate];
+};
+
+Sanitizer.clearPluginData = Task.async(function* (range) {
+  // Clear plugin data.
+  // As evidenced in bug 1253204, clearing plugin data can sometimes be
+  // very, very long, for mysterious reasons. Unfortunately, this is not
+  // something actionable by Mozilla, so crashing here serves no purpose.
+  //
+  // For this reason, instead of waiting for sanitization to always
+  // complete, we introduce a soft timeout. Once this timeout has
+  // elapsed, we proceed with the shutdown of Firefox.
+  let seenException;
+
+  let promiseClearPluginData = Task.async(function* () {
+    const FLAG_CLEAR_ALL = Ci.nsIPluginHost.FLAG_CLEAR_ALL;
+    let ph = Cc["@mozilla.org/plugin/host;1"].getService(Ci.nsIPluginHost);
+
+    // Determine age range in seconds. (-1 means clear all.) We don't know
+    // that range[1] is actually now, so we compute age range based
+    // on the lower bound. If range results in a negative age, do nothing.
+    let age = range ? (Date.now() / 1000 - range[0] / 1000000) : -1;
+    if (!range || age >= 0) {
+      let tags = ph.getPluginTags();
+      for (let tag of tags) {
+        let refObj = {};
+        let probe = "";
+        if (/\bFlash\b/.test(tag.name)) {
+          probe = tag.loaded ? "FX_SANITIZE_LOADED_FLASH"
+                             : "FX_SANITIZE_UNLOADED_FLASH";
+          TelemetryStopwatch.start(probe, refObj);
+        }
+        try {
+          let rv = yield new Promise(resolve =>
+            ph.clearSiteData(tag, null, FLAG_CLEAR_ALL, age, resolve)
+          );
+          // If the plugin doesn't support clearing by age, clear everything.
+          if (rv == Components.results.NS_ERROR_PLUGIN_TIME_RANGE_NOT_SUPPORTED) {
+            yield new Promise(resolve =>
+              ph.clearSiteData(tag, null, FLAG_CLEAR_ALL, -1, resolve)
+            );
+          }
+          if (probe) {
+            TelemetryStopwatch.finish(probe, refObj);
+          }
+        } catch (ex) {
+          // Ignore errors from plug-ins
+          if (probe) {
+            TelemetryStopwatch.cancel(probe, refObj);
+          }
+        }
+      }
+    }
+  });
+
+  try {
+    // We don't want to wait for this operation to complete...
+    promiseClearPluginData = promiseClearPluginData(range);
+
+    // ... at least, not for more than 10 seconds.
+    yield Promise.race([
+      promiseClearPluginData,
+      new Promise(resolve => setTimeout(resolve, 10000 /* 10 seconds */))
+    ]);
+  } catch (ex) {
+    seenException = ex;
+  }
+
+  // Detach waiting for plugin data to be cleared.
+  promiseClearPluginData.catch(() => {
+    // If this exception is raised before the soft timeout, it
+    // will appear in `seenException`. Otherwise, it's too late
+    // to do anything about it.
+  });
+
+  if (seenException) {
+    throw seenException;
+  }
+});
+
+Sanitizer._prefs = null;
+Sanitizer.__defineGetter__("prefs", function() {
+  return Sanitizer._prefs ? Sanitizer._prefs
+    : Sanitizer._prefs = Components.classes["@mozilla.org/preferences-service;1"]
+                         .getService(Components.interfaces.nsIPrefService)
+                         .getBranch(Sanitizer.PREF_DOMAIN);
+});
+
+// Shows sanitization UI
+Sanitizer.showUI = function(aParentWindow) {
+#ifdef XP_MACOSX
+  let win = null;
+#else
+  let win = aParentWindow;
+#endif
+  Services.ww.openWindow(win,
+                         "chrome://browser/content/sanitize.xul",
+                         "Sanitize",
+                         "chrome,titlebar,dialog,centerscreen,modal",
+                         null);
+};
+
+/**
+ * Deletes privacy sensitive data in a batch, optionally showing the
+ * sanitize UI, according to user preferences
+ */
+Sanitizer.sanitize = function(aParentWindow) {
+  Sanitizer.showUI(aParentWindow);
+};
+
+Sanitizer.onStartup = Task.async(function*() {
+  // Check if we were interrupted during the last shutdown sanitization.
+  let shutownSanitizationWasInterrupted =
+    Preferences.get(Sanitizer.PREF_SANITIZE_ON_SHUTDOWN, false) &&
+    !Preferences.has(Sanitizer.PREF_SANITIZE_DID_SHUTDOWN);
+
+  if (Preferences.has(Sanitizer.PREF_SANITIZE_DID_SHUTDOWN)) {
+    // Reset the pref, so that if we crash before having a chance to
+    // sanitize on shutdown, we will do at the next startup.
+    // Flushing prefs has a cost, so do this only if necessary.
+    Preferences.reset(Sanitizer.PREF_SANITIZE_DID_SHUTDOWN);
+    Services.prefs.savePrefFile(null);
+  }
+
+  // Make sure that we are triggered during shutdown.
+  let shutdownClient = Cc["@mozilla.org/browser/nav-history-service;1"]
+                         .getService(Ci.nsPIPlacesDatabase)
+                         .shutdownClient
+                         .jsclient;
+  // We need to pass to sanitize() (through sanitizeOnShutdown) a state object
+  // that tracks the status of the shutdown blocker. This `progress` object
+  // will be updated during sanitization and reported with the crash in case of
+  // a shutdown timeout.
+  // We use the `options` argument to pass the `progress` object to sanitize().
+  let progress = { isShutdown: true };
+  shutdownClient.addBlocker("sanitize.js: Sanitize on shutdown",
+    () => sanitizeOnShutdown({ progress }),
+    {
+      fetchState: () => ({ progress })
+    }
+  );
+
+  // Check if Firefox crashed during a sanitization.
+  let lastInterruptedSanitization = Preferences.get(Sanitizer.PREF_SANITIZE_IN_PROGRESS, "");
+  if (lastInterruptedSanitization) {
+    let s = new Sanitizer();
+    // If the json is invalid this will just throw and reject the Task.
+    let itemsToClear = JSON.parse(lastInterruptedSanitization);
+    yield s.sanitize(itemsToClear);
+  } else if (shutownSanitizationWasInterrupted) {
+    // Otherwise, could be we were supposed to sanitize on shutdown but we
+    // didn't have a chance, due to an earlier crash.
+    // In such a case, just redo a shutdown sanitize now, during startup.
+    yield sanitizeOnShutdown();
+  }
+});
+
+var sanitizeOnShutdown = Task.async(function*(options = {}) {
+  if (!Preferences.get(Sanitizer.PREF_SANITIZE_ON_SHUTDOWN)) {
+    return;
+  }
+  // Need to sanitize upon shutdown
+  let s = new Sanitizer();
+  s.prefDomain = "privacy.clearOnShutdown.";
+  s.isShutDown = true;
+  yield s.sanitize(null, options);
+  // We didn't crash during shutdown sanitization, so annotate it to avoid
+  // sanitizing again on startup.
+  Preferences.set(Sanitizer.PREF_SANITIZE_DID_SHUTDOWN, true);
+  Services.prefs.savePrefFile(null);
+});