• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright 2020 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 #pragma once
17 
18 #include <array>
19 #include <chrono>
20 #include <cstdint>
21 #include <list>
22 #include <memory>
23 #include <mutex>
24 #include <string>
25 
26 #include "hci/address.h"
27 #include "module.h"
28 #include "storage/config_cache.h"
29 #include "storage/device.h"
30 #include "storage/mutation.h"
31 
32 namespace bluetooth {
33 
34 namespace shim {
35 class BtifConfigInterface;
36 }
37 
38 namespace security::internal {
39 class SecurityManagerImpl;
40 }
41 
42 namespace hci {
43 class AclManager;
44 }
45 
46 namespace storage {
47 
48 class StorageModule : public bluetooth::Module {
49  public:
50   static const std::string kInfoSection;
51   static const std::string kFileSourceProperty;
52   static const std::string kTimeCreatedProperty;
53   static const std::string kTimeCreatedFormat;
54 
55   static const std::string kAdapterSection;
56 
57   StorageModule(const StorageModule&) = delete;
58   StorageModule& operator=(const StorageModule&) = delete;
59 
60   ~StorageModule();
61   static const ModuleFactory Factory;
62 
63   // Methods to access the storage layer via Device abstraction
64   // - Devices will be lazily created when methods below are called. Hence, no std::optional<> nor nullptr is used in
65   //   the return type. User of the API can use the Device object's API to find out if the device has existed before
66   // - Devices with no config values will not be saved to config cache
67   // - Devices that are not paired will also be discarded when stack shutdown
68 
69   // Concept:
70   //
71   // BR/EDR Address:
72   //  -> Public static address only, begin with 3 byte IEEE assigned OUI number
73   //
74   // BLE Addresses
75   //  -> Public Address: begin with IEEE assigned OUI number
76   //     -> Static: static public address do not change
77   //     -> Private/Variable: We haven't seen private/variable public address yet
78   //  -> Random Address: randomly generated, does not begin with IEEE assigned OUI number
79   //     -> Static: static random address do not change
80   //     -> Private/Variable: private random address changes once so often
81   //        -> Resolvable: this address can be resolved into a static address using identity resolving key (IRK)
82   //        -> Non-resolvable: this address is for temporary use only, do not save this address
83   //
84   // MAC addresses are six bytes only and hence are only regionally unique
85 
86   // Get a device object using the |legacy_key_address|. In legacy config, each device's config is stored in a config
87   // section keyed by a single MAC address. For BR/EDR device, this is straightforward as a BR/EDR device has only a
88   // single public static MAC address. However, for LE devices using private addresses, we only learn its real static
89   // address after pairing. Since we still need to store that device's information prior to pairing, we use the
90   // first-seen address of that device, no matter random private or static public, as a "key" to store that device's
91   // config. This method gives you a device object using this legacy key. If the key does not exist, the device will
92   // be lazily created in the config
93   Device GetDeviceByLegacyKey(hci::Address legacy_key_address);
94 
95   // A classic (BR/EDR) or dual mode device can be uniquely located by its classic (BR/EDR) MAC address
96   Device GetDeviceByClassicMacAddress(hci::Address classic_address);
97 
98   // A LE or dual mode device can be uniquely located by its identity address that is either:
99   //   -> Public static address
100   //   -> Random static address
101   // If remote device uses LE random private resolvable address, user of this API must resolve its identity address
102   // before calling this method to get the device object
103   //
104   // Note: A dual mode device's identity address is normally the same as its BR/EDR address, but they can also be
105   // different. Hence, please don't make such assumption and don't use GetDeviceByBrEdrMacAddress() interchangeably
106   Device GetDeviceByLeIdentityAddress(hci::Address le_identity_address);
107 
108   // Get a list of bonded devices from config
109   std::vector<Device> GetBondedDevices();
110 
111   // Modify the underlying config by starting a mutation. All entries in the mutation will be applied atomically when
112   // Commit() is called. User should never touch ConfigCache() directly.
113   Mutation Modify();
114 
115  protected:
116   void ListDependencies(ModuleList* list) const override;
117   void Start() override;
118   void Stop() override;
119   std::string ToString() const override;
120 
121   friend shim::BtifConfigInterface;
122   friend hci::AclManager;
123   friend security::internal::SecurityManagerImpl;
124   // For unit test only
125   ConfigCache* GetMemoryOnlyConfigCache();
126   // Normally, underlying config will be saved at most 3 seconds after the first config change in a series of changes
127   // This method triggers the delayed saving automatically, the delay is equal to |config_save_delay_|
128   void SaveDelayed();
129   // In some cases, one may want to save the config immediately to disk. Call this method with caution as it runs
130   // immediately on the calling thread
131   void SaveImmediately();
132   // remove all content in this config cache, restore it to the state after the explicit constructor
133   void Clear();
134 
135   // Create the storage module where:
136   // - config_file_path is the path to the config file on disk, a .bak file will be created with the original
137   // - config_save_delay is the duration after which to dump config to disk after SaveDelayed() is called
138   // - temp_devices_capacity is the number of temporary, typically unpaired devices to hold in a memory based LRU
139   // - is_restricted_mode and is_single_user_mode are flags from upper layer
140   StorageModule(
141       std::string config_file_path,
142       std::chrono::milliseconds config_save_delay,
143       size_t temp_devices_capacity,
144       bool is_restricted_mode,
145       bool is_single_user_mode);
146 
147   bool HasSection(const std::string& section) const;
148   bool HasProperty(const std::string& section, const std::string& property) const;
149 
150   std::optional<std::string> GetProperty(
151       const std::string& section, const std::string& property) const;
152   void SetProperty(std::string section, std::string property, std::string value);
153 
154   std::vector<std::string> GetPersistentSections() const;
155 
156   void RemoveSection(const std::string& section);
157   bool RemoveProperty(const std::string& section, const std::string& property);
158   void ConvertEncryptOrDecryptKeyIfNeeded();
159   // Remove sections with |property| set
160   void RemoveSectionWithProperty(const std::string& property);
161 
162   void SetBool(const std::string& section, const std::string& property, bool value);
163   std::optional<bool> GetBool(const std::string& section, const std::string& property) const;
164   void SetUint64(const std::string& section, const std::string& property, uint64_t value);
165   std::optional<uint64_t> GetUint64(const std::string& section, const std::string& property) const;
166   void SetUint32(const std::string& section, const std::string& property, uint32_t value);
167   std::optional<uint32_t> GetUint32(const std::string& section, const std::string& property) const;
168   void SetInt64(const std::string& section, const std::string& property, int64_t value);
169   std::optional<int64_t> GetInt64(const std::string& section, const std::string& property) const;
170   void SetInt(const std::string& section, const std::string& property, int value);
171   std::optional<int> GetInt(const std::string& section, const std::string& property) const;
172   void SetBin(
173       const std::string& section, const std::string& property, const std::vector<uint8_t>& value);
174   std::optional<std::vector<uint8_t>> GetBin(
175       const std::string& section, const std::string& property) const;
176 
177  private:
178   struct impl;
179   mutable std::recursive_mutex mutex_;
180   std::unique_ptr<impl> pimpl_;
181   std::string config_file_path_;
182   std::string config_backup_path_;
183   std::chrono::milliseconds config_save_delay_;
184   size_t temp_devices_capacity_;
185   bool is_restricted_mode_;
186   bool is_single_user_mode_;
187   static bool is_config_checksum_pass(int check_bit);
188 };
189 
190 }  // namespace storage
191 }  // namespace bluetooth
192