Use default wallpaper at login screen when user choose a custom wallpaper

chrome/browser/chromeos/login/wallpaper_manager.cc

 // Copyright (c) 2012 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.
 
 #include "chrome/browser/chromeos/login/wallpaper_manager.h"
 
 #include "ash/desktop_background/desktop_background_controller.h"
 #include "ash/shell.h"
 #include "base/command_line.h"
 #include "base/logging.h"
@@ skipping 381 matching lines @@
     return;
 
   User::WallpaperType type;
   int index;
   base::Time date;
   GetUserWallpaperProperties(email, &type, &index, &date);
   if (type == User::DAILY && date != base::Time::Now().LocalMidnight()) {
     index = ash::GetNextWallpaperIndex(index);
     SaveUserWallpaperProperties(email, User::DAILY, index);
   } else if (type == User::CUSTOMIZED) {
-    gfx::ImageSkia custom_wallpaper;
-    if (GetCustomWallpaperFromCache(email, &custom_wallpaper)) {
-      // In customized mode, we use index pref to save the user selected
-      // wallpaper layout. See function SaveWallpaperToLocalState().
-      ash::WallpaperLayout layout = static_cast<ash::WallpaperLayout>(index);
-      ash::Shell::GetInstance()->desktop_background_controller()->
-          SetCustomWallpaper(custom_wallpaper, layout);
+    // For security reason, use default wallpaper instead of custom wallpaper
+    // at login screen. The security issue is tracked in issue 143198. Once it
+    // fixed, we should then only use custom wallpaper.
+    if (!UserManager::Get()->IsUserLoggedIn()) {
+      index = ash::GetDefaultWallpaperIndex();
     } else {
       FetchCustomWallpaper(email);
+      return;
     }
-    return;
   }
   ash::Shell::GetInstance()->desktop_background_controller()->
       SetDefaultWallpaper(index, false);
   SetLastSelectedUser(email);
 }
 
 void WallpaperManager::SetWallpaperFromImageSkia(
     const gfx::ImageSkia& wallpaper,
     ash::WallpaperLayout layout) {
   ash::Shell::GetInstance()->desktop_background_controller()->
@@ skipping 60 matching lines @@
     }
   }
 }
 
 void WallpaperManager::CacheUserWallpaper(const std::string& email) {
   User::WallpaperType type;
   int index;
   base::Time date;
   GetUserWallpaperProperties(email, &type, &index, &date);
   if (type == User::CUSTOMIZED) {
-    std::string wallpaper_path = GetWallpaperPathForUser(email, false).value();
-
-    // Uses WeakPtr here to make the request cancelable.
-    wallpaper_loader_->Start(wallpaper_path, 0,
-                             base::Bind(&WallpaperManager::CacheWallpaper,
-                                        weak_factory_.GetWeakPtr(), email));
+    ash::Shell::GetInstance()->desktop_background_controller()->
+        CacheDefaultWallpaper(ash::GetDefaultWallpaperIndex());
   } else {
     ash::Shell::GetInstance()->desktop_background_controller()->
         CacheDefaultWallpaper(index);
   }
 }
 
 void WallpaperManager::CacheWallpaper(const std::string& email,
                                       const UserImage& wallpaper) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(custom_wallpaper_cache_.find(email) == custom_wallpaper_cache_.end());
@@ skipping 141 matching lines @@
 
 void WallpaperManager::SystemResumed() {
   BatchUpdateWallpaper();
 }
 
 void WallpaperManager::TimezoneChanged(const icu::TimeZone& timezone) {
   RestartTimer();
 }
 
 }  // chromeos