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