chromeos/cryptohome/system_salt_getter.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROMEOS_CRYPTOHOME_SYSTEM_SALT_GETTER_H_
   6 #define CHROMEOS_CRYPTOHOME_SYSTEM_SALT_GETTER_H_
   7
   8 #include <string>
   9 #include <vector>
  10
  11 #include "base/basictypes.h"
  12 #include "base/callback_forward.h"
  13 #include "base/memory/weak_ptr.h"
  14 #include "chromeos/chromeos_export.h"
  15 #include "chromeos/dbus/dbus_method_call_status.h"
  16
  17 namespace chromeos {
  18
  19 // This class is used to get the system salt from cryptohome and cache it.
  20 class CHROMEOS_EXPORT SystemSaltGetter {
  21  public:
  22   typedef base::Callback<void(const std::string& system_salt)>
  23       GetSystemSaltCallback;
  24
  25   // Manage an explicitly initialized global instance.
  26   static void Initialize();
  27   static bool IsInitialized();
  28   static void Shutdown();
  29   static SystemSaltGetter* Get();
  30
  31   // Converts |salt| to a hex encoded string.
  32   static std::string ConvertRawSaltToHexString(const std::vector<uint8>& salt);
  33
  34   // Returns system hash in hex encoded ascii format. Note: this may return
  35   // an empty string (e.g. errors in D-Bus layer)
  36   void GetSystemSalt(const GetSystemSaltCallback& callback);
  37
  38  protected:
  39   SystemSaltGetter();
  40   ~SystemSaltGetter();
  41
  42  private:
  43   // Used to implement GetSystemSalt().
  44   void DidWaitForServiceToBeAvailable(const GetSystemSaltCallback& callback,
  45                                       bool service_is_available);
  46   void DidGetSystemSalt(const GetSystemSaltCallback& callback,
  47                         DBusMethodCallStatus call_status,
  48                         const std::vector<uint8>& system_salt);
  49
  50   std::string system_salt_;
  51
  52   base::WeakPtrFactory<SystemSaltGetter> weak_ptr_factory_;
  53
  54   DISALLOW_COPY_AND_ASSIGN(SystemSaltGetter);
  55 };
  56
  57 }  // namespace chromeos
  58
  59 #endif  // CHROMEOS_CRYPTOHOME_SYSTEM_SALT_GETTER_H_