chrome/browser/extensions/api/music_manager_private/device_id.h

   1 // Copyright 2013 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 CHROME_BROWSER_EXTENSIONS_API_MUSIC_MANAGER_PRIVATE_DEVICE_ID_H_
   6 #define CHROME_BROWSER_EXTENSIONS_API_MUSIC_MANAGER_PRIVATE_DEVICE_ID_H_
   7
   8 #include <string>
   9
  10 #include "base/bind.h"
  11
  12 namespace extensions {
  13 namespace api {
  14
  15 class DeviceId {
  16  public:
  17   typedef base::Callback<void(const std::string&)> IdCallback;
  18
  19   // Calls |callback| with a unique device identifier as argument. The device
  20   // identifier has the following characteristics:
  21   // 1. It is shared across users of a device.
  22   // 2. It is resilient to device reboots.
  23   // 3. It can be reset in *some* way by the user. In Particular, it can *not*
  24   //    be based only on a MAC address of a physical device.
  25   // The specific implementation varies across platforms, some of them requiring
  26   // a round trip to the IO or FILE thread. "callback" will always be called on
  27   // the UI thread though (sometimes directly if the implementation allows
  28   // running on the UI thread).
  29   // The returned value is HMAC_SHA256(|raw_device_id|, |extension_id|), so that
  30   // the actual device identifier value is not exposed directly to the caller.
  31   static void GetDeviceId(const std::string& extension_id,
  32                           const IdCallback& callback);
  33
  34  private:
  35   // Platform specific implementation of "raw" machine ID retrieval.
  36   static void GetRawDeviceId(const IdCallback& callback);
  37
  38   // On some platforms, part of the machine ID is the MAC address. This function
  39   // is shared across platforms to filter out MAC addresses that have been
  40   // identified as invalid, i.e. not unique. For example, some VM hosts assign a
  41   // new MAC addresses at each reboot.
  42   static bool IsValidMacAddress(const void* bytes, size_t size);
  43 };
  44
  45 }  // namespace api
  46 }  // namespace extensions
  47
  48 #endif  // CHROME_BROWSER_EXTENSIONS_API_MUSIC_MANAGER_PRIVATE_DEVICE_ID_H_