Bug 894595 - part 1.5 - Move privacy level checks into a module; r=yoric

browser/components/sessionstore/src/PrivacyLevel.jsm

@@ -0,0 +1,82 @@
+/* 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/. */
+
+"use strict";
+
+this.EXPORTED_SYMBOLS = ["PrivacyLevel"];
+
+const Cu = Components.utils;
+
+Cu.import("resource://gre/modules/Services.jsm");
+
+const PREF_NORMAL = "browser.sessionstore.privacy_level";
+const PREF_DEFERRED = "browser.sessionstore.privacy_level_deferred";
+
+// The following constants represent the different possible privacy levels that
+// can be set by the user and that we need to consider when collecting text
+// data, cookies, and POSTDATA.
+//
+// Collect data from all sites (http and https).
+const PRIVACY_NONE = 0;
+// Collect data from unencrypted sites (http), only.
+const PRIVACY_ENCRYPTED = 1;
+// Collect no data.
+const PRIVACY_FULL = 2;
+
+/**
+ * Returns whether we will resume the session automatically on next startup.
+ */
+function willResumeAutomatically() {
+  return Services.prefs.getIntPref("browser.startup.page") == 3 ||
+         Services.prefs.getBoolPref("browser.sessionstore.resume_session_once");
+}
+
+/**
+ * Determines the current privacy level as set by the user.
+ *
+ * @param isPinned
+ *        Whether to return the privacy level for pinned tabs.
+ * @return {int} The privacy level as read from the user's preferences.
+ */
+function getCurrentLevel(isPinned) {
+  let pref = PREF_NORMAL;
+
+  // If we're in the process of quitting and we're not autoresuming the session
+  // then we will use the deferred privacy level for non-pinned tabs.
+  if (!isPinned && Services.startup.shuttingDown && !willResumeAutomatically()) {
+    pref = PREF_DEFERRED;
+  }
+
+  return Services.prefs.getIntPref(pref);
+}
+
+/**
+ * The external API as exposed by this module.
+ */
+let PrivacyLevel = Object.freeze({
+  /**
+   * Checks whether we're allowed to save data for a specific site.
+   *
+   * @param {isHttps: boolean, isPinned: boolean}
+   *        An object that must have two properties: 'isHttps' and 'isPinned'.
+   *        'isHttps' tells whether the site us secure communication (HTTPS).
+   *        'isPinned' tells whether the site is loaded in a pinned tab.
+   * @return {bool} Whether we can save data for the specified site.
+   */
+  canSave: function ({isHttps, isPinned}) {
+    let level = getCurrentLevel(isPinned);
+
+    // Never save any data when full privacy is requested.
+    if (level == PRIVACY_FULL) {
+      return false;
+    }
+
+    // Don't save data for encrypted sites when requested.
+    if (isHttps && level == PRIVACY_ENCRYPTED) {
+      return false;
+    }
+
+    return true;
+  }
+});

browser/components/sessionstore/src/SessionCookies.jsm

@@ -12,8 +12,8 @@ const Ci = Components.interfaces;
 Cu.import("resource://gre/modules/Services.jsm", this);
 Cu.import("resource://gre/modules/XPCOMUtils.jsm", this);
 
-XPCOMUtils.defineLazyModuleGetter(this, "SessionStore",
-  "resource:///modules/sessionstore/SessionStore.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "PrivacyLevel",
+  "resource:///modules/sessionstore/PrivacyLevel.jsm");
 
 // MAX_EXPIRY should be 2^63-1, but JavaScript can't handle that precision.
 const MAX_EXPIRY = Math.pow(2, 62);
@@ -67,8 +67,8 @@ let SessionCookiesInternal = {
         for (let cookie of CookieStore.getCookiesForHost(host)) {
           // _getCookiesForHost() will only return hosts with the right privacy
           // rules, so there is no need to do anything special with this call
-          // to checkPrivacyLevel().
-          if (SessionStore.checkPrivacyLevel(cookie.secure, isPinned)) {
+          // to PrivacyLevel.canSave().
+          if (PrivacyLevel.canSave({isHttps: cookie.secure, isPinned: isPinned})) {
             cookies.push(cookie);
           }
         }
@@ -209,7 +209,7 @@ let SessionCookiesInternal = {
     // case testing scheme will be sufficient.
     if (/https?/.test(scheme) && !hosts[host] &&
         (!checkPrivacy ||
-         SessionStore.checkPrivacyLevel(scheme == "https", isPinned))) {
+         PrivacyLevel.canSave({isHttps: scheme == "https", isPinned: isPinned}))) {
       // By setting this to true or false, we can determine when looking at
       // the host in update() if we should check for privacy.
       hosts[host] = isPinned;

browser/components/sessionstore/src/SessionStorage.jsm

@@ -11,8 +11,8 @@ const Cu = Components.utils;
 Cu.import("resource://gre/modules/Services.jsm");
 Cu.import("resource://gre/modules/XPCOMUtils.jsm");
 
-XPCOMUtils.defineLazyModuleGetter(this, "SessionStore",
-  "resource:///modules/sessionstore/SessionStore.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "PrivacyLevel",
+  "resource:///modules/sessionstore/PrivacyLevel.jsm");
 
 this.SessionStorage = {
   /**
@@ -59,8 +59,8 @@ let DomStorage = {
         continue;
 
       // Check if we're allowed to store sessionStorage data.
-      let isHTTPS = principal.URI && principal.URI.schemeIs("https");
-      if (aFullData || SessionStore.checkPrivacyLevel(isHTTPS, isPinned)) {
+      let isHttps = principal.URI && principal.URI.schemeIs("https");
+      if (aFullData || PrivacyLevel.canSave({isHttps: isHttps, isPinned: isPinned})) {
         let origin = principal.jarPrefix + principal.origin;
 
         // Don't read a host twice.

browser/components/sessionstore/src/SessionStore.jsm

@@ -21,10 +21,6 @@ const STATE_RUNNING_STR = "running";
 const TAB_STATE_NEEDS_RESTORE = 1;
 const TAB_STATE_RESTORING = 2;
 
-const PRIVACY_NONE = 0;
-const PRIVACY_ENCRYPTED = 1;
-const PRIVACY_FULL = 2;
-
 const NOTIFY_WINDOWS_RESTORED = "sessionstore-windows-restored";
 const NOTIFY_BROWSER_STATE_RESTORED = "sessionstore-browser-state-restored";
 
@@ -128,6 +124,8 @@ XPCOMUtils.defineLazyModuleGetter(this, "ScratchpadManager",
   "resource:///modules/devtools/scratchpad-manager.jsm");
 XPCOMUtils.defineLazyModuleGetter(this, "DocumentUtils",
   "resource:///modules/sessionstore/DocumentUtils.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "PrivacyLevel",
+  "resource:///modules/sessionstore/PrivacyLevel.jsm");
 XPCOMUtils.defineLazyModuleGetter(this, "SessionSaver",
   "resource:///modules/sessionstore/SessionSaver.jsm");
 XPCOMUtils.defineLazyModuleGetter(this, "SessionStorage",
@@ -271,10 +269,6 @@ this.SessionStore = {
     SessionStoreInternal.restoreLastSession();
   },
 
-  checkPrivacyLevel: function ss_checkPrivacyLevel(aIsHTTPS, aUseDefaultPref) {
-    return SessionStoreInternal.checkPrivacyLevel(aIsHTTPS, aUseDefaultPref);
-  },
-
   getCurrentState: function (aUpdateAll) {
     return SessionStoreInternal.getCurrentState(aUpdateAll);
   },
@@ -3288,25 +3282,6 @@ let SessionStoreInternal = {
     return !hasFirstArgument;
   },
 
-  /**
-   * don't save sensitive data if the user doesn't want to
-   * (distinguishes between encrypted and non-encrypted sites)
-   * @param aIsHTTPS
-   *        Bool is encrypted
-   * @param aUseDefaultPref
-   *        don't do normal check for deferred
-   * @returns bool
-   */
-  checkPrivacyLevel: function ssi_checkPrivacyLevel(aIsHTTPS, aUseDefaultPref) {
-    let pref = "sessionstore.privacy_level";
-    // If we're in the process of quitting and we're not autoresuming the session
-    // then we should treat it as a deferred session. We have a different privacy
-    // pref for that case.
-    if (!aUseDefaultPref && this._loadState == STATE_QUITTING && !this._doResumeSession())
-      pref = "sessionstore.privacy_level_deferred";
-    return this._prefBranch.getIntPref(pref) < (aIsHTTPS ? PRIVACY_ENCRYPTED : PRIVACY_FULL);
-  },
-
   /**
    * on popup windows, the XULWindow's attributes seem not to be set correctly
    * we use thus JSDOMWindow attributes for sizemode and normal window attributes
@@ -4552,9 +4527,10 @@ let TabState = {
       entry.scroll = x.value + "," + y.value;
 
     try {
+      let isHttps = shEntry.URI.schemeIs("https");
       let prefPostdata = Services.prefs.getIntPref("browser.sessionstore.postdata");
       if (shEntry.postData && (includePrivateData || prefPostdata &&
-          SessionStoreInternal.checkPrivacyLevel(shEntry.URI.schemeIs("https"), isPinned))) {
+          PrivacyLevel.canSave({isHttps: isHttps, isPinned: isPinned}))) {
         shEntry.postData.QueryInterface(Ci.nsISeekableStream).
                         seek(Ci.nsISeekableStream.NS_SEEK_SET, 0);
         let stream = Cc["@mozilla.org/binaryinputstream;1"].
@@ -4714,10 +4690,11 @@ let TabState = {
                                               includePrivateData, isPinned);
     }
     let href = (content.parent || content).document.location.href;
-    let isHTTPS = makeURI(href).schemeIs("https");
+    let isHttps = makeURI(href).schemeIs("https");
     let topURL = content.top.document.location.href;
     let isAboutSR = topURL == "about:sessionrestore" || topURL == "about:welcomeback";
-    if (includePrivateData || SessionStoreInternal.checkPrivacyLevel(isHTTPS, isPinned) || isAboutSR) {
+    if (includePrivateData || isAboutSR ||
+        PrivacyLevel.canSave({isHttps: isHttps, isPinned: isPinned})) {
       let formData = DocumentUtils.getFormData(content.document);
 
       // We want to avoid saving data for about:sessionrestore as a string.

browser/components/sessionstore/src/moz.build

@@ -14,6 +14,7 @@ JS_MODULES_PATH = 'modules/sessionstore'
 
 EXTRA_JS_MODULES = [
     'DocumentUtils.jsm',
+    'PrivacyLevel.jsm',
     'SessionCookies.jsm',
     'SessionMigration.jsm',
     'SessionStorage.jsm',