extensions/browser/api/device_permissions_manager.cc

   1 // Copyright 2014 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 "extensions/browser/api/device_permissions_manager.h"
   6
   7 #include "base/bind.h"
   8 #include "base/memory/singleton.h"
   9 #include "base/strings/string_number_conversions.h"
  10 #include "base/strings/stringprintf.h"
  11 #include "base/strings/utf_string_conversions.h"
  12 #include "base/values.h"
  13 #include "components/keyed_service/content/browser_context_dependency_manager.h"
  14 #include "content/public/browser/browser_thread.h"
  15 #include "device/core/device_client.h"
  16 #include "device/hid/hid_device_info.h"
  17 #include "device/hid/hid_service.h"
  18 #include "device/usb/usb_device.h"
  19 #include "device/usb/usb_ids.h"
  20 #include "extensions/browser/extension_host.h"
  21 #include "extensions/browser/extension_prefs.h"
  22 #include "extensions/browser/extensions_browser_client.h"
  23 #include "extensions/common/value_builder.h"
  24 #include "extensions/strings/grit/extensions_strings.h"
  25 #include "ui/base/l10n/l10n_util.h"
  26
  27 namespace extensions {
  28
  29 using content::BrowserContext;
  30 using content::BrowserThread;
  31 using device::HidDeviceInfo;
  32 using device::HidService;
  33 using device::UsbDevice;
  34 using device::UsbService;
  35 using extensions::APIPermission;
  36 using extensions::Extension;
  37 using extensions::ExtensionHost;
  38 using extensions::ExtensionPrefs;
  39
  40 namespace {
  41
  42 // Preference keys
  43
  44 // The device that the app has permission to access.
  45 const char kDevices[] = "devices";
  46
  47 // The type of device saved.
  48 const char kDeviceType[] = "type";
  49
  50 // Type identifier for USB devices.
  51 const char kDeviceTypeUsb[] = "usb";
  52
  53 // Type identifier for HID devices.
  54 const char kDeviceTypeHid[] = "hid";
  55
  56 // The vendor ID of the device that the app had permission to access.
  57 const char kDeviceVendorId[] = "vendor_id";
  58
  59 // The product ID of the device that the app had permission to access.
  60 const char kDeviceProductId[] = "product_id";
  61
  62 // The serial number of the device that the app has permission to access.
  63 const char kDeviceSerialNumber[] = "serial_number";
  64
  65 // The manufacturer string read from the device that the app has permission to
  66 // access.
  67 const char kDeviceManufacturerString[] = "manufacturer_string";
  68
  69 // The product string read from the device that the app has permission to
  70 // access.
  71 const char kDeviceProductString[] = "product_string";
  72
  73 // Serialized timestamp of the last time when the device was opened by the app.
  74 const char kDeviceLastUsed[] = "last_used_time";
  75
  76 // Converts a DevicePermissionEntry::Type to a string for the prefs file.
  77 const char* TypeToString(DevicePermissionEntry::Type type) {
  78   switch (type) {
  79     case DevicePermissionEntry::Type::USB:
  80       return kDeviceTypeUsb;
  81     case DevicePermissionEntry::Type::HID:
  82       return kDeviceTypeHid;
  83   }
  84   NOTREACHED();
  85   return "";
  86 }
  87
  88 // Persists a DevicePermissionEntry in ExtensionPrefs.
  89 void SaveDevicePermissionEntry(BrowserContext* context,
  90                                const std::string& extension_id,
  91                                scoped_refptr<DevicePermissionEntry> entry) {
  92   ExtensionPrefs* prefs = ExtensionPrefs::Get(context);
  93   ExtensionPrefs::ScopedListUpdate update(prefs, extension_id, kDevices);
  94   base::ListValue* devices = update.Get();
  95   if (!devices) {
  96     devices = update.Create();
  97   }
  98
  99   scoped_ptr<base::Value> device_entry(entry->ToValue());
 100   DCHECK(devices->Find(*device_entry.get()) == devices->end());
 101   devices->Append(device_entry.release());
 102 }
 103
 104 bool MatchesDevicePermissionEntry(const base::DictionaryValue* value,
 105                                   scoped_refptr<DevicePermissionEntry> entry) {
 106   std::string type;
 107   if (!value->GetStringWithoutPathExpansion(kDeviceType, &type) ||
 108       type != TypeToString(entry->type())) {
 109     return false;
 110   }
 111   int vendor_id;
 112   if (!value->GetIntegerWithoutPathExpansion(kDeviceVendorId, &vendor_id) ||
 113       vendor_id != entry->vendor_id()) {
 114     return false;
 115   }
 116   int product_id;
 117   if (!value->GetIntegerWithoutPathExpansion(kDeviceProductId, &product_id) ||
 118       product_id != entry->product_id()) {
 119     return false;
 120   }
 121   base::string16 serial_number;
 122   if (!value->GetStringWithoutPathExpansion(kDeviceSerialNumber,
 123                                             &serial_number) ||
 124       serial_number != entry->serial_number()) {
 125     return false;
 126   }
 127   return true;
 128 }
 129
 130 // Updates the timestamp stored in ExtensionPrefs for the given
 131 // DevicePermissionEntry.
 132 void UpdateDevicePermissionEntry(BrowserContext* context,
 133                                  const std::string& extension_id,
 134                                  scoped_refptr<DevicePermissionEntry> entry) {
 135   ExtensionPrefs* prefs = ExtensionPrefs::Get(context);
 136   ExtensionPrefs::ScopedListUpdate update(prefs, extension_id, kDevices);
 137   base::ListValue* devices = update.Get();
 138   if (!devices) {
 139     return;
 140   }
 141
 142   for (size_t i = 0; i < devices->GetSize(); ++i) {
 143     base::DictionaryValue* dict_value;
 144     if (!devices->GetDictionary(i, &dict_value)) {
 145       continue;
 146     }
 147     if (!MatchesDevicePermissionEntry(dict_value, entry)) {
 148       continue;
 149     }
 150     devices->Set(i, entry->ToValue().release());
 151     break;
 152   }
 153 }
 154
 155 // Removes the given DevicePermissionEntry from ExtensionPrefs.
 156 void RemoveDevicePermissionEntry(BrowserContext* context,
 157                                  const std::string& extension_id,
 158                                  scoped_refptr<DevicePermissionEntry> entry) {
 159   ExtensionPrefs* prefs = ExtensionPrefs::Get(context);
 160   ExtensionPrefs::ScopedListUpdate update(prefs, extension_id, kDevices);
 161   base::ListValue* devices = update.Get();
 162   if (!devices) {
 163     return;
 164   }
 165
 166   for (size_t i = 0; i < devices->GetSize(); ++i) {
 167     base::DictionaryValue* dict_value;
 168     if (!devices->GetDictionary(i, &dict_value)) {
 169       continue;
 170     }
 171     if (!MatchesDevicePermissionEntry(dict_value, entry)) {
 172       continue;
 173     }
 174     devices->Remove(i, nullptr);
 175     break;
 176   }
 177 }
 178
 179 // Clears all DevicePermissionEntries for the app from ExtensionPrefs.
 180 void ClearDevicePermissionEntries(ExtensionPrefs* prefs,
 181                                   const std::string& extension_id) {
 182   prefs->UpdateExtensionPref(extension_id, kDevices, NULL);
 183 }
 184
 185 scoped_refptr<DevicePermissionEntry> ReadDevicePermissionEntry(
 186     const base::DictionaryValue* entry) {
 187   int vendor_id;
 188   if (!entry->GetIntegerWithoutPathExpansion(kDeviceVendorId, &vendor_id) ||
 189       vendor_id < 0 || vendor_id > UINT16_MAX) {
 190     return nullptr;
 191   }
 192
 193   int product_id;
 194   if (!entry->GetIntegerWithoutPathExpansion(kDeviceProductId, &product_id) ||
 195       product_id < 0 || product_id > UINT16_MAX) {
 196     return nullptr;
 197   }
 198
 199   base::string16 serial_number;
 200   if (!entry->GetStringWithoutPathExpansion(kDeviceSerialNumber,
 201                                             &serial_number)) {
 202     return nullptr;
 203   }
 204
 205   base::string16 manufacturer_string;
 206   // Ignore failure as this string is optional.
 207   entry->GetStringWithoutPathExpansion(kDeviceManufacturerString,
 208                                        &manufacturer_string);
 209
 210   base::string16 product_string;
 211   // Ignore failure as this string is optional.
 212   entry->GetStringWithoutPathExpansion(kDeviceProductString, &product_string);
 213
 214   // If a last used time is not stored in ExtensionPrefs last_used.is_null()
 215   // will be true.
 216   std::string last_used_str;
 217   int64 last_used_i64 = 0;
 218   base::Time last_used;
 219   if (entry->GetStringWithoutPathExpansion(kDeviceLastUsed, &last_used_str) &&
 220       base::StringToInt64(last_used_str, &last_used_i64)) {
 221     last_used = base::Time::FromInternalValue(last_used_i64);
 222   }
 223
 224   std::string type;
 225   if (!entry->GetStringWithoutPathExpansion(kDeviceType, &type)) {
 226     return nullptr;
 227   }
 228
 229   if (type == kDeviceTypeUsb) {
 230     return new DevicePermissionEntry(
 231         DevicePermissionEntry::Type::USB, vendor_id, product_id, serial_number,
 232         manufacturer_string, product_string, last_used);
 233   } else if (type == kDeviceTypeHid) {
 234     return new DevicePermissionEntry(
 235         DevicePermissionEntry::Type::HID, vendor_id, product_id, serial_number,
 236         base::string16(), product_string, last_used);
 237   }
 238   return nullptr;
 239 }
 240
 241 // Returns all DevicePermissionEntries for the app.
 242 std::set<scoped_refptr<DevicePermissionEntry>> GetDevicePermissionEntries(
 243     ExtensionPrefs* prefs,
 244     const std::string& extension_id) {
 245   std::set<scoped_refptr<DevicePermissionEntry>> result;
 246   const base::ListValue* devices = NULL;
 247   if (!prefs->ReadPrefAsList(extension_id, kDevices, &devices)) {
 248     return result;
 249   }
 250
 251   for (const base::Value* entry : *devices) {
 252     const base::DictionaryValue* entry_dict;
 253     if (entry->GetAsDictionary(&entry_dict)) {
 254       scoped_refptr<DevicePermissionEntry> device_entry =
 255           ReadDevicePermissionEntry(entry_dict);
 256       if (entry_dict) {
 257         result.insert(device_entry);
 258       }
 259     }
 260   }
 261   return result;
 262 }
 263
 264 }  // namespace
 265
 266 DevicePermissionEntry::DevicePermissionEntry(scoped_refptr<UsbDevice> device)
 267     : usb_device_(device),
 268       type_(Type::USB),
 269       vendor_id_(device->vendor_id()),
 270       product_id_(device->product_id()),
 271       serial_number_(device->serial_number()),
 272       manufacturer_string_(device->manufacturer_string()),
 273       product_string_(device->product_string()) {
 274 }
 275
 276 DevicePermissionEntry::DevicePermissionEntry(
 277     scoped_refptr<HidDeviceInfo> device)
 278     : hid_device_(device),
 279       type_(Type::HID),
 280       vendor_id_(device->vendor_id()),
 281       product_id_(device->product_id()),
 282       serial_number_(base::UTF8ToUTF16(device->serial_number())),
 283       product_string_(base::UTF8ToUTF16(device->product_name())) {
 284 }
 285
 286 DevicePermissionEntry::DevicePermissionEntry(
 287     Type type,
 288     uint16_t vendor_id,
 289     uint16_t product_id,
 290     const base::string16& serial_number,
 291     const base::string16& manufacturer_string,
 292     const base::string16& product_string,
 293     const base::Time& last_used)
 294     : type_(type),
 295       vendor_id_(vendor_id),
 296       product_id_(product_id),
 297       serial_number_(serial_number),
 298       manufacturer_string_(manufacturer_string),
 299       product_string_(product_string),
 300       last_used_(last_used) {
 301 }
 302
 303 DevicePermissionEntry::~DevicePermissionEntry() {
 304 }
 305
 306 bool DevicePermissionEntry::IsPersistent() const {
 307   return !serial_number_.empty();
 308 }
 309
 310 scoped_ptr<base::Value> DevicePermissionEntry::ToValue() const {
 311   if (!IsPersistent()) {
 312     return nullptr;
 313   }
 314
 315   DCHECK(!serial_number_.empty());
 316   scoped_ptr<base::DictionaryValue> entry_dict(
 317       DictionaryBuilder()
 318           .Set(kDeviceType, TypeToString(type_))
 319           .Set(kDeviceVendorId, vendor_id_)
 320           .Set(kDeviceProductId, product_id_)
 321           .Set(kDeviceSerialNumber, serial_number_)
 322           .Build());
 323
 324   if (!manufacturer_string_.empty()) {
 325     entry_dict->SetStringWithoutPathExpansion(kDeviceManufacturerString,
 326                                               manufacturer_string_);
 327   }
 328   if (!product_string_.empty()) {
 329     entry_dict->SetStringWithoutPathExpansion(kDeviceProductString,
 330                                               product_string_);
 331   }
 332   if (!last_used_.is_null()) {
 333     entry_dict->SetStringWithoutPathExpansion(
 334         kDeviceLastUsed, base::Int64ToString(last_used_.ToInternalValue()));
 335   }
 336
 337   return entry_dict.Pass();
 338 }
 339
 340 base::string16 DevicePermissionEntry::GetPermissionMessageString() const {
 341   return DevicePermissionsManager::GetPermissionMessage(
 342       vendor_id_, product_id_, manufacturer_string_, product_string_,
 343       serial_number_, type_ == Type::USB);
 344 }
 345
 346 DevicePermissions::~DevicePermissions() {
 347 }
 348
 349 scoped_refptr<DevicePermissionEntry> DevicePermissions::FindUsbDeviceEntry(
 350     scoped_refptr<UsbDevice> device) const {
 351   const auto& ephemeral_device_entry =
 352       ephemeral_usb_devices_.find(device.get());
 353   if (ephemeral_device_entry != ephemeral_usb_devices_.end()) {
 354     return ephemeral_device_entry->second;
 355   }
 356
 357   if (device->serial_number().empty()) {
 358     return nullptr;
 359   }
 360
 361   for (const auto& entry : entries_) {
 362     if (entry->IsPersistent() && entry->vendor_id() == device->vendor_id() &&
 363         entry->product_id() == device->product_id() &&
 364         entry->serial_number() == device->serial_number()) {
 365       return entry;
 366     }
 367   }
 368   return nullptr;
 369 }
 370
 371 scoped_refptr<DevicePermissionEntry> DevicePermissions::FindHidDeviceEntry(
 372     scoped_refptr<HidDeviceInfo> device) const {
 373   const auto& ephemeral_device_entry =
 374       ephemeral_hid_devices_.find(device.get());
 375   if (ephemeral_device_entry != ephemeral_hid_devices_.end()) {
 376     return ephemeral_device_entry->second;
 377   }
 378
 379   if (device->serial_number().empty()) {
 380     return nullptr;
 381   }
 382
 383   base::string16 serial_number = base::UTF8ToUTF16(device->serial_number());
 384   for (const auto& entry : entries_) {
 385     if (entry->IsPersistent() && entry->vendor_id() == device->vendor_id() &&
 386         entry->product_id() == device->product_id() &&
 387         entry->serial_number() == serial_number) {
 388       return entry;
 389     }
 390   }
 391   return nullptr;
 392 }
 393
 394 DevicePermissions::DevicePermissions(BrowserContext* context,
 395                                      const std::string& extension_id) {
 396   ExtensionPrefs* prefs = ExtensionPrefs::Get(context);
 397   entries_ = GetDevicePermissionEntries(prefs, extension_id);
 398 }
 399
 400 // static
 401 DevicePermissionsManager* DevicePermissionsManager::Get(
 402     BrowserContext* context) {
 403   return DevicePermissionsManagerFactory::GetForBrowserContext(context);
 404 }
 405
 406 // static
 407 base::string16 DevicePermissionsManager::GetPermissionMessage(
 408     uint16 vendor_id,
 409     uint16 product_id,
 410     const base::string16& manufacturer_string,
 411     const base::string16& product_string,
 412     const base::string16& serial_number,
 413     bool always_include_manufacturer) {
 414   base::string16 product = product_string;
 415   if (product.empty()) {
 416     const char* product_name =
 417         device::UsbIds::GetProductName(vendor_id, product_id);
 418     if (product_name) {
 419       product = base::UTF8ToUTF16(product_name);
 420     }
 421   }
 422
 423   base::string16 manufacturer = manufacturer_string;
 424   if (manufacturer_string.empty()) {
 425     const char* vendor_name = device::UsbIds::GetVendorName(vendor_id);
 426     if (vendor_name) {
 427       manufacturer = base::UTF8ToUTF16(vendor_name);
 428     }
 429   }
 430
 431   if (serial_number.empty()) {
 432     if (product.empty()) {
 433       product = base::ASCIIToUTF16(base::StringPrintf("%04x", product_id));
 434       if (manufacturer.empty()) {
 435         manufacturer =
 436             base::ASCIIToUTF16(base::StringPrintf("%04x", vendor_id));
 437         return l10n_util::GetStringFUTF16(
 438             IDS_DEVICE_NAME_WITH_UNKNOWN_PRODUCT_UNKNOWN_VENDOR, product,
 439             manufacturer);
 440       } else {
 441         return l10n_util::GetStringFUTF16(
 442             IDS_DEVICE_NAME_WITH_UNKNOWN_PRODUCT_VENDOR, product, manufacturer);
 443       }
 444     } else {
 445       if (always_include_manufacturer) {
 446         if (manufacturer.empty()) {
 447           manufacturer =
 448               base::ASCIIToUTF16(base::StringPrintf("%04x", vendor_id));
 449           return l10n_util::GetStringFUTF16(
 450               IDS_DEVICE_NAME_WITH_PRODUCT_UNKNOWN_VENDOR, product,
 451               manufacturer);
 452         } else {
 453           return l10n_util::GetStringFUTF16(IDS_DEVICE_NAME_WITH_PRODUCT_VENDOR,
 454                                             product, manufacturer);
 455         }
 456       } else {
 457         return product;
 458       }
 459     }
 460   } else {
 461     if (product.empty()) {
 462       product = base::ASCIIToUTF16(base::StringPrintf("%04x", product_id));
 463       if (manufacturer.empty()) {
 464         manufacturer =
 465             base::ASCIIToUTF16(base::StringPrintf("%04x", vendor_id));
 466         return l10n_util::GetStringFUTF16(
 467             IDS_DEVICE_NAME_WITH_UNKNOWN_PRODUCT_UNKNOWN_VENDOR_SERIAL, product,
 468             manufacturer, serial_number);
 469       } else {
 470         return l10n_util::GetStringFUTF16(
 471             IDS_DEVICE_NAME_WITH_UNKNOWN_PRODUCT_VENDOR_SERIAL, product,
 472             manufacturer, serial_number);
 473       }
 474     } else {
 475       if (always_include_manufacturer) {
 476         if (manufacturer.empty()) {
 477           manufacturer =
 478               base::ASCIIToUTF16(base::StringPrintf("%04x", vendor_id));
 479           return l10n_util::GetStringFUTF16(
 480               IDS_DEVICE_NAME_WITH_PRODUCT_UNKNOWN_VENDOR_SERIAL, product,
 481               manufacturer, serial_number);
 482         } else {
 483           return l10n_util::GetStringFUTF16(
 484               IDS_DEVICE_NAME_WITH_PRODUCT_VENDOR_SERIAL, product, manufacturer,
 485               serial_number);
 486         }
 487       } else {
 488         return l10n_util::GetStringFUTF16(IDS_DEVICE_NAME_WITH_PRODUCT_SERIAL,
 489                                           product, serial_number);
 490       }
 491     }
 492   }
 493 }
 494
 495 DevicePermissions* DevicePermissionsManager::GetForExtension(
 496     const std::string& extension_id) {
 497   DCHECK(thread_checker_.CalledOnValidThread());
 498   DevicePermissions* device_permissions = GetInternal(extension_id);
 499   if (!device_permissions) {
 500     device_permissions = new DevicePermissions(context_, extension_id);
 501     extension_id_to_device_permissions_[extension_id] = device_permissions;
 502   }
 503
 504   return device_permissions;
 505 }
 506
 507 std::vector<base::string16>
 508 DevicePermissionsManager::GetPermissionMessageStrings(
 509     const std::string& extension_id) const {
 510   DCHECK(thread_checker_.CalledOnValidThread());
 511   std::vector<base::string16> messages;
 512   const DevicePermissions* device_permissions = GetInternal(extension_id);
 513   if (device_permissions) {
 514     for (const scoped_refptr<DevicePermissionEntry>& entry :
 515          device_permissions->entries()) {
 516       messages.push_back(entry->GetPermissionMessageString());
 517     }
 518   }
 519   return messages;
 520 }
 521
 522 void DevicePermissionsManager::AllowUsbDevice(const std::string& extension_id,
 523                                               scoped_refptr<UsbDevice> device) {
 524   DCHECK(thread_checker_.CalledOnValidThread());
 525   DevicePermissions* device_permissions = GetForExtension(extension_id);
 526
 527   scoped_refptr<DevicePermissionEntry> device_entry(
 528       new DevicePermissionEntry(device));
 529
 530   if (device_entry->IsPersistent()) {
 531     for (const auto& entry : device_permissions->entries()) {
 532       if (entry->vendor_id() == device_entry->vendor_id() &&
 533           entry->product_id() == device_entry->product_id() &&
 534           entry->serial_number() == device_entry->serial_number()) {
 535         return;
 536       }
 537     }
 538
 539     device_permissions->entries_.insert(device_entry);
 540     SaveDevicePermissionEntry(context_, extension_id, device_entry);
 541   } else if (!ContainsKey(device_permissions->ephemeral_usb_devices_,
 542                           device.get())) {
 543     // Non-persistent devices cannot be reliably identified when they are
 544     // reconnected so such devices are only remembered until disconnect.
 545     // Register an observer here so that this set doesn't grow undefinitely.
 546     device_permissions->entries_.insert(device_entry);
 547     device_permissions->ephemeral_usb_devices_[device.get()] = device_entry;
 548
 549     // Only start observing when an ephemeral device has been added so that
 550     // UsbService is not automatically initialized on profile creation (which it
 551     // would be if this call were in the constructor).
 552     UsbService* usb_service = device::DeviceClient::Get()->GetUsbService();
 553     if (!usb_service_observer_.IsObserving(usb_service)) {
 554       usb_service_observer_.Add(usb_service);
 555     }
 556   }
 557 }
 558
 559 void DevicePermissionsManager::AllowHidDevice(
 560     const std::string& extension_id,
 561     scoped_refptr<HidDeviceInfo> device) {
 562   DCHECK(thread_checker_.CalledOnValidThread());
 563   DevicePermissions* device_permissions = GetForExtension(extension_id);
 564
 565   scoped_refptr<DevicePermissionEntry> device_entry(
 566       new DevicePermissionEntry(device));
 567
 568   if (device_entry->IsPersistent()) {
 569     for (const auto& entry : device_permissions->entries()) {
 570       if (entry->vendor_id() == device_entry->vendor_id() &&
 571           entry->product_id() == device_entry->product_id() &&
 572           entry->serial_number() == device_entry->serial_number()) {
 573         return;
 574       }
 575     }
 576
 577     device_permissions->entries_.insert(device_entry);
 578     SaveDevicePermissionEntry(context_, extension_id, device_entry);
 579   } else if (!ContainsKey(device_permissions->ephemeral_hid_devices_,
 580                           device.get())) {
 581     // Non-persistent devices cannot be reliably identified when they are
 582     // reconnected so such devices are only remembered until disconnect.
 583     // Register an observer here so that this set doesn't grow undefinitely.
 584     device_permissions->entries_.insert(device_entry);
 585     device_permissions->ephemeral_hid_devices_[device.get()] = device_entry;
 586
 587     // Only start observing when an ephemeral device has been added so that
 588     // HidService is not automatically initialized on profile creation (which it
 589     // would be if this call were in the constructor).
 590     HidService* hid_service = device::DeviceClient::Get()->GetHidService();
 591     if (!hid_service_observer_.IsObserving(hid_service)) {
 592       hid_service_observer_.Add(hid_service);
 593     }
 594   }
 595 }
 596
 597 void DevicePermissionsManager::UpdateLastUsed(
 598     const std::string& extension_id,
 599     scoped_refptr<DevicePermissionEntry> entry) {
 600   DCHECK(thread_checker_.CalledOnValidThread());
 601   entry->set_last_used(base::Time::Now());
 602   if (entry->IsPersistent()) {
 603     UpdateDevicePermissionEntry(context_, extension_id, entry);
 604   }
 605 }
 606
 607 void DevicePermissionsManager::RemoveEntry(
 608     const std::string& extension_id,
 609     scoped_refptr<DevicePermissionEntry> entry) {
 610   DCHECK(thread_checker_.CalledOnValidThread());
 611   DevicePermissions* device_permissions = GetInternal(extension_id);
 612   DCHECK(device_permissions);
 613   DCHECK(ContainsKey(device_permissions->entries_, entry));
 614   device_permissions->entries_.erase(entry);
 615   if (entry->IsPersistent()) {
 616     RemoveDevicePermissionEntry(context_, extension_id, entry);
 617   } else if (entry->type_ == DevicePermissionEntry::Type::USB) {
 618     device_permissions->ephemeral_usb_devices_.erase(entry->usb_device_.get());
 619   } else if (entry->type_ == DevicePermissionEntry::Type::HID) {
 620     device_permissions->ephemeral_hid_devices_.erase(entry->hid_device_.get());
 621   } else {
 622     NOTREACHED();
 623   }
 624 }
 625
 626 void DevicePermissionsManager::Clear(const std::string& extension_id) {
 627   DCHECK(thread_checker_.CalledOnValidThread());
 628
 629   ClearDevicePermissionEntries(ExtensionPrefs::Get(context_), extension_id);
 630   DevicePermissions* device_permissions = GetInternal(extension_id);
 631   if (device_permissions) {
 632     extension_id_to_device_permissions_.erase(extension_id);
 633     delete device_permissions;
 634   }
 635 }
 636
 637 DevicePermissionsManager::DevicePermissionsManager(
 638     content::BrowserContext* context)
 639     : context_(context),
 640       usb_service_observer_(this),
 641       hid_service_observer_(this) {
 642 }
 643
 644 DevicePermissionsManager::~DevicePermissionsManager() {
 645   for (const auto& map_entry : extension_id_to_device_permissions_) {
 646     DevicePermissions* device_permissions = map_entry.second;
 647     delete device_permissions;
 648   }
 649 }
 650
 651 DevicePermissions* DevicePermissionsManager::GetInternal(
 652     const std::string& extension_id) const {
 653   std::map<std::string, DevicePermissions*>::const_iterator it =
 654       extension_id_to_device_permissions_.find(extension_id);
 655   if (it != extension_id_to_device_permissions_.end()) {
 656     return it->second;
 657   }
 658
 659   return NULL;
 660 }
 661
 662 void DevicePermissionsManager::OnDeviceRemovedCleanup(
 663     scoped_refptr<UsbDevice> device) {
 664   DCHECK(thread_checker_.CalledOnValidThread());
 665   for (const auto& map_entry : extension_id_to_device_permissions_) {
 666     // An ephemeral device cannot be identified if it is reconnected and so
 667     // permission to access it is cleared on disconnect.
 668     DevicePermissions* device_permissions = map_entry.second;
 669     const auto& device_entry =
 670         device_permissions->ephemeral_usb_devices_.find(device.get());
 671     if (device_entry != device_permissions->ephemeral_usb_devices_.end()) {
 672       device_permissions->entries_.erase(device_entry->second);
 673       device_permissions->ephemeral_usb_devices_.erase(device_entry);
 674     }
 675   }
 676 }
 677
 678 void DevicePermissionsManager::OnDeviceRemovedCleanup(
 679     scoped_refptr<device::HidDeviceInfo> device) {
 680   DCHECK(thread_checker_.CalledOnValidThread());
 681   for (const auto& map_entry : extension_id_to_device_permissions_) {
 682     // An ephemeral device cannot be identified if it is reconnected and so
 683     // permission to access it is cleared on disconnect.
 684     DevicePermissions* device_permissions = map_entry.second;
 685     const auto& device_entry =
 686         device_permissions->ephemeral_hid_devices_.find(device.get());
 687     if (device_entry != device_permissions->ephemeral_hid_devices_.end()) {
 688       device_permissions->entries_.erase(device_entry->second);
 689       device_permissions->ephemeral_hid_devices_.erase(device_entry);
 690     }
 691   }
 692 }
 693
 694 // static
 695 DevicePermissionsManager* DevicePermissionsManagerFactory::GetForBrowserContext(
 696     content::BrowserContext* context) {
 697   return static_cast<DevicePermissionsManager*>(
 698       GetInstance()->GetServiceForBrowserContext(context, true));
 699 }
 700
 701 // static
 702 DevicePermissionsManagerFactory*
 703 DevicePermissionsManagerFactory::GetInstance() {
 704   return base::Singleton<DevicePermissionsManagerFactory>::get();
 705 }
 706
 707 DevicePermissionsManagerFactory::DevicePermissionsManagerFactory()
 708     : BrowserContextKeyedServiceFactory(
 709           "DevicePermissionsManager",
 710           BrowserContextDependencyManager::GetInstance()) {
 711 }
 712
 713 DevicePermissionsManagerFactory::~DevicePermissionsManagerFactory() {
 714 }
 715
 716 KeyedService* DevicePermissionsManagerFactory::BuildServiceInstanceFor(
 717     content::BrowserContext* context) const {
 718   return new DevicePermissionsManager(context);
 719 }
 720
 721 BrowserContext* DevicePermissionsManagerFactory::GetBrowserContextToUse(
 722     BrowserContext* context) const {
 723   // Return the original (possibly off-the-record) browser context so that a
 724   // separate instance of the DevicePermissionsManager is used in incognito
 725   // mode. The parent class's implemenation returns NULL.
 726   return context;
 727 }
 728
 729 }  // namespace extensions