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
12namespace extensions {
13namespace api {
14
15class 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_
49