chromeos/cryptohome/system_salt_getter.cc

   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 #include "chromeos/cryptohome/system_salt_getter.h"
   6
   7 #include "base/bind.h"
   8 #include "base/location.h"
   9 #include "base/single_thread_task_runner.h"
  10 #include "base/strings/string_number_conversions.h"
  11 #include "base/strings/string_util.h"
  12 #include "base/thread_task_runner_handle.h"
  13 #include "chromeos/dbus/cryptohome_client.h"
  14 #include "chromeos/dbus/dbus_thread_manager.h"
  15
  16 namespace chromeos {
  17 namespace {
  18
  19 SystemSaltGetter* g_system_salt_getter = NULL;
  20
  21 }  // namespace
  22
  23 SystemSaltGetter::SystemSaltGetter() : weak_ptr_factory_(this) {
  24 }
  25
  26 SystemSaltGetter::~SystemSaltGetter() {
  27 }
  28
  29 void SystemSaltGetter::GetSystemSalt(
  30     const GetSystemSaltCallback& callback) {
  31   if (!system_salt_.empty()) {
  32     base::ThreadTaskRunnerHandle::Get()->PostTask(
  33         FROM_HERE, base::Bind(callback, system_salt_));
  34     return;
  35   }
  36
  37   DBusThreadManager::Get()->GetCryptohomeClient()->WaitForServiceToBeAvailable(
  38       base::Bind(&SystemSaltGetter::DidWaitForServiceToBeAvailable,
  39                  weak_ptr_factory_.GetWeakPtr(),
  40                  callback));
  41 }
  42
  43 void SystemSaltGetter::DidWaitForServiceToBeAvailable(
  44     const GetSystemSaltCallback& callback,
  45     bool service_is_available) {
  46   if (!service_is_available) {
  47     LOG(ERROR) << "WaitForServiceToBeAvailable failed.";
  48     callback.Run(std::string());
  49     return;
  50   }
  51   DBusThreadManager::Get()->GetCryptohomeClient()->GetSystemSalt(
  52       base::Bind(&SystemSaltGetter::DidGetSystemSalt,
  53                  weak_ptr_factory_.GetWeakPtr(),
  54                  callback));
  55 }
  56
  57 void SystemSaltGetter::DidGetSystemSalt(const GetSystemSaltCallback& callback,
  58                                         DBusMethodCallStatus call_status,
  59                                         const std::vector<uint8>& system_salt) {
  60   if (call_status == DBUS_METHOD_CALL_SUCCESS &&
  61       !system_salt.empty() &&
  62       system_salt.size() % 2 == 0U)
  63     system_salt_ = ConvertRawSaltToHexString(system_salt);
  64   else
  65     LOG(WARNING) << "System salt not available";
  66
  67   callback.Run(system_salt_);
  68 }
  69
  70 // static
  71 void SystemSaltGetter::Initialize() {
  72   CHECK(!g_system_salt_getter);
  73   g_system_salt_getter = new SystemSaltGetter();
  74 }
  75
  76 // static
  77 bool SystemSaltGetter::IsInitialized() {
  78   return g_system_salt_getter;
  79 }
  80
  81 // static
  82 void SystemSaltGetter::Shutdown() {
  83   CHECK(g_system_salt_getter);
  84   delete g_system_salt_getter;
  85   g_system_salt_getter = NULL;
  86 }
  87
  88 // static
  89 SystemSaltGetter* SystemSaltGetter::Get() {
  90   CHECK(g_system_salt_getter)
  91       << "SystemSaltGetter::Get() called before Initialize()";
  92   return g_system_salt_getter;
  93 }
  94
  95 // static
  96 std::string SystemSaltGetter::ConvertRawSaltToHexString(
  97     const std::vector<uint8>& salt) {
  98   return base::ToLowerASCII(
  99       base::HexEncode(reinterpret_cast<const void*>(salt.data()), salt.size()));
 100 }
 101
 102 }  // namespace chromeos