components/storage_monitor/storage_monitor_linux.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 // StorageMonitorLinux implementation.
   6
   7 #include "components/storage_monitor/storage_monitor_linux.h"
   8
   9 #include <mntent.h>
  10 #include <stdio.h>
  11
  12 #include <list>
  13
  14 #include "base/basictypes.h"
  15 #include "base/bind.h"
  16 #include "base/metrics/histogram.h"
  17 #include "base/process/kill.h"
  18 #include "base/process/launch.h"
  19 #include "base/stl_util.h"
  20 #include "base/strings/string_number_conversions.h"
  21 #include "base/strings/string_util.h"
  22 #include "base/strings/utf_string_conversions.h"
  23 #include "components/storage_monitor/media_storage_util.h"
  24 #include "components/storage_monitor/media_transfer_protocol_device_observer_linux.h"
  25 #include "components/storage_monitor/removable_device_constants.h"
  26 #include "components/storage_monitor/storage_info.h"
  27 #include "components/storage_monitor/udev_util_linux.h"
  28 #include "device/media_transfer_protocol/media_transfer_protocol_manager.h"
  29 #include "device/udev_linux/udev.h"
  30
  31 using content::BrowserThread;
  32
  33 namespace storage_monitor {
  34
  35 typedef MtabWatcherLinux::MountPointDeviceMap MountPointDeviceMap;
  36
  37 namespace {
  38
  39 // udev device property constants.
  40 const char kBlockSubsystemKey[] = "block";
  41 const char kDiskDeviceTypeKey[] = "disk";
  42 const char kFsUUID[] = "ID_FS_UUID";
  43 const char kLabel[] = "ID_FS_LABEL";
  44 const char kModel[] = "ID_MODEL";
  45 const char kModelID[] = "ID_MODEL_ID";
  46 const char kRemovableSysAttr[] = "removable";
  47 const char kSerialShort[] = "ID_SERIAL_SHORT";
  48 const char kSizeSysAttr[] = "size";
  49 const char kVendor[] = "ID_VENDOR";
  50 const char kVendorID[] = "ID_VENDOR_ID";
  51
  52 // Construct a device id using label or manufacturer (vendor and model) details.
  53 std::string MakeDeviceUniqueId(struct udev_device* device) {
  54   std::string uuid = GetUdevDevicePropertyValue(device, kFsUUID);
  55   // Keep track of device uuid, to see how often we receive empty uuid values.
  56   UMA_HISTOGRAM_BOOLEAN(
  57       "RemovableDeviceNotificationsLinux.device_file_system_uuid_available",
  58       !uuid.empty());
  59
  60   if (!uuid.empty())
  61     return kFSUniqueIdPrefix + uuid;
  62
  63   // If one of the vendor, model, serial information is missing, its value
  64   // in the string is empty.
  65   // Format: VendorModelSerial:VendorInfo:ModelInfo:SerialShortInfo
  66   // E.g.: VendorModelSerial:Kn:DataTravel_12.10:8000000000006CB02CDB
  67   std::string vendor = GetUdevDevicePropertyValue(device, kVendorID);
  68   std::string model = GetUdevDevicePropertyValue(device, kModelID);
  69   std::string serial_short = GetUdevDevicePropertyValue(device,
  70                                                         kSerialShort);
  71   if (vendor.empty() && model.empty() && serial_short.empty())
  72     return std::string();
  73
  74   return kVendorModelSerialPrefix + vendor + ":" + model + ":" + serial_short;
  75 }
  76
  77 // Records GetDeviceInfo result on destruction, to see how often we fail to get
  78 // device details.
  79 class ScopedGetDeviceInfoResultRecorder {
  80  public:
  81   ScopedGetDeviceInfoResultRecorder() : result_(false) {}
  82   ~ScopedGetDeviceInfoResultRecorder() {
  83     UMA_HISTOGRAM_BOOLEAN("MediaDeviceNotification.UdevRequestSuccess",
  84                           result_);
  85   }
  86
  87   void set_result(bool result) {
  88     result_ = result;
  89   }
  90
  91  private:
  92   bool result_;
  93
  94   DISALLOW_COPY_AND_ASSIGN(ScopedGetDeviceInfoResultRecorder);
  95 };
  96
  97 // Returns the storage partition size of the device specified by |device_path|.
  98 // If the requested information is unavailable, returns 0.
  99 uint64 GetDeviceStorageSize(const base::FilePath& device_path,
 100                             struct udev_device* device) {
 101   // sysfs provides the device size in units of 512-byte blocks.
 102   const std::string partition_size = udev_device_get_sysattr_value(
 103       device, kSizeSysAttr);
 104
 105   // Keep track of device size, to see how often this information is
 106   // unavailable.
 107   UMA_HISTOGRAM_BOOLEAN(
 108       "RemovableDeviceNotificationsLinux.device_partition_size_available",
 109       !partition_size.empty());
 110
 111   uint64 total_size_in_bytes = 0;
 112   if (!base::StringToUint64(partition_size, &total_size_in_bytes))
 113     return 0;
 114   return (total_size_in_bytes <= kuint64max / 512) ?
 115       total_size_in_bytes * 512 : 0;
 116 }
 117
 118 // Gets the device information using udev library.
 119 scoped_ptr<StorageInfo> GetDeviceInfo(const base::FilePath& device_path,
 120                                       const base::FilePath& mount_point) {
 121   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 122   DCHECK(!device_path.empty());
 123
 124   scoped_ptr<StorageInfo> storage_info;
 125
 126   ScopedGetDeviceInfoResultRecorder results_recorder;
 127
 128   device::ScopedUdevPtr udev_obj(udev_new());
 129   if (!udev_obj.get())
 130     return storage_info.Pass();
 131
 132   struct stat device_stat;
 133   if (stat(device_path.value().c_str(), &device_stat) < 0)
 134     return storage_info.Pass();
 135
 136   char device_type;
 137   if (S_ISCHR(device_stat.st_mode))
 138     device_type = 'c';
 139   else if (S_ISBLK(device_stat.st_mode))
 140     device_type = 'b';
 141   else
 142     return storage_info.Pass();  // Not a supported type.
 143
 144   device::ScopedUdevDevicePtr device(
 145       udev_device_new_from_devnum(udev_obj.get(), device_type,
 146                                   device_stat.st_rdev));
 147   if (!device.get())
 148     return storage_info.Pass();
 149
 150   base::string16 volume_label =
 151       base::UTF8ToUTF16(GetUdevDevicePropertyValue(device.get(), kLabel));
 152   base::string16 vendor_name =
 153       base::UTF8ToUTF16(GetUdevDevicePropertyValue(device.get(), kVendor));
 154   base::string16 model_name =
 155       base::UTF8ToUTF16(GetUdevDevicePropertyValue(device.get(), kModel));
 156
 157   std::string unique_id = MakeDeviceUniqueId(device.get());
 158
 159   // Keep track of device info details to see how often we get invalid values.
 160   MediaStorageUtil::RecordDeviceInfoHistogram(true, unique_id, volume_label);
 161
 162   const char* value =
 163       udev_device_get_sysattr_value(device.get(), kRemovableSysAttr);
 164   if (!value) {
 165     // |parent_device| is owned by |device| and does not need to be cleaned
 166     // up.
 167     struct udev_device* parent_device =
 168         udev_device_get_parent_with_subsystem_devtype(device.get(),
 169                                                       kBlockSubsystemKey,
 170                                                       kDiskDeviceTypeKey);
 171     value = udev_device_get_sysattr_value(parent_device, kRemovableSysAttr);
 172   }
 173   const bool is_removable = (value && atoi(value) == 1);
 174
 175   StorageInfo::Type type = StorageInfo::FIXED_MASS_STORAGE;
 176   if (is_removable) {
 177     if (MediaStorageUtil::HasDcim(mount_point))
 178       type = StorageInfo::REMOVABLE_MASS_STORAGE_WITH_DCIM;
 179     else
 180       type = StorageInfo::REMOVABLE_MASS_STORAGE_NO_DCIM;
 181   }
 182
 183   results_recorder.set_result(true);
 184
 185   storage_info.reset(new StorageInfo(
 186       StorageInfo::MakeDeviceId(type, unique_id),
 187       mount_point.value(),
 188       volume_label,
 189       vendor_name,
 190       model_name,
 191       GetDeviceStorageSize(device_path, device.get())));
 192   return storage_info.Pass();
 193 }
 194
 195 MtabWatcherLinux* CreateMtabWatcherLinuxOnFileThread(
 196     const base::FilePath& mtab_path,
 197     base::WeakPtr<MtabWatcherLinux::Delegate> delegate) {
 198   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 199   // Owned by caller.
 200   return new MtabWatcherLinux(mtab_path, delegate);
 201 }
 202
 203 StorageMonitor::EjectStatus EjectPathOnFileThread(
 204     const base::FilePath& path,
 205     const base::FilePath& device) {
 206   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 207
 208   // Note: Linux LSB says umount should exist in /bin.
 209   static const char kUmountBinary[] = "/bin/umount";
 210   std::vector<std::string> command;
 211   command.push_back(kUmountBinary);
 212   command.push_back(path.value());
 213
 214   base::LaunchOptions options;
 215   base::ProcessHandle handle;
 216   if (!base::LaunchProcess(command, options, &handle))
 217     return StorageMonitor::EJECT_FAILURE;
 218
 219   int exit_code = -1;
 220   if (!base::WaitForExitCodeWithTimeout(handle, &exit_code,
 221       base::TimeDelta::FromMilliseconds(3000))) {
 222     base::KillProcess(handle, -1, false);
 223     base::EnsureProcessTerminated(handle);
 224     return StorageMonitor::EJECT_FAILURE;
 225   }
 226
 227   // TODO(gbillock): Make sure this is found in documentation
 228   // somewhere. Experimentally it seems to hold that exit code
 229   // 1 means device is in use.
 230   if (exit_code == 1)
 231     return StorageMonitor::EJECT_IN_USE;
 232   if (exit_code != 0)
 233     return StorageMonitor::EJECT_FAILURE;
 234
 235   return StorageMonitor::EJECT_OK;
 236 }
 237
 238 }  // namespace
 239
 240 StorageMonitorLinux::StorageMonitorLinux(const base::FilePath& path)
 241     : mtab_path_(path),
 242       get_device_info_callback_(base::Bind(&GetDeviceInfo)),
 243       weak_ptr_factory_(this) {
 244   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 245 }
 246
 247 StorageMonitorLinux::~StorageMonitorLinux() {
 248   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 249 }
 250
 251 void StorageMonitorLinux::Init() {
 252   DCHECK(!mtab_path_.empty());
 253
 254   BrowserThread::PostTaskAndReplyWithResult(
 255       BrowserThread::FILE, FROM_HERE,
 256       base::Bind(&CreateMtabWatcherLinuxOnFileThread,
 257                  mtab_path_,
 258                  weak_ptr_factory_.GetWeakPtr()),
 259       base::Bind(&StorageMonitorLinux::OnMtabWatcherCreated,
 260                  weak_ptr_factory_.GetWeakPtr()));
 261
 262   if (!media_transfer_protocol_manager_) {
 263     scoped_refptr<base::MessageLoopProxy> loop_proxy =
 264         BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE);
 265     media_transfer_protocol_manager_.reset(
 266         device::MediaTransferProtocolManager::Initialize(loop_proxy));
 267   }
 268
 269   media_transfer_protocol_device_observer_.reset(
 270       new MediaTransferProtocolDeviceObserverLinux(
 271           receiver(), media_transfer_protocol_manager_.get()));
 272 }
 273
 274 bool StorageMonitorLinux::GetStorageInfoForPath(
 275     const base::FilePath& path,
 276     StorageInfo* device_info) const {
 277   DCHECK(device_info);
 278   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 279
 280   // TODO(thestig) |media_transfer_protocol_device_observer_| should always be
 281   // valid.
 282   if (media_transfer_protocol_device_observer_ &&
 283       media_transfer_protocol_device_observer_->GetStorageInfoForPath(
 284           path, device_info)) {
 285     return true;
 286   }
 287
 288   if (!path.IsAbsolute())
 289     return false;
 290
 291   base::FilePath current = path;
 292   while (!ContainsKey(mount_info_map_, current) && current != current.DirName())
 293     current = current.DirName();
 294
 295   MountMap::const_iterator mount_info = mount_info_map_.find(current);
 296   if (mount_info == mount_info_map_.end())
 297     return false;
 298   *device_info = mount_info->second.storage_info;
 299   return true;
 300 }
 301
 302 device::MediaTransferProtocolManager*
 303 StorageMonitorLinux::media_transfer_protocol_manager() {
 304   return media_transfer_protocol_manager_.get();
 305 }
 306
 307 void StorageMonitorLinux::SetGetDeviceInfoCallbackForTest(
 308     const GetDeviceInfoCallback& get_device_info_callback) {
 309   get_device_info_callback_ = get_device_info_callback;
 310 }
 311
 312 void StorageMonitorLinux::SetMediaTransferProtocolManagerForTest(
 313     device::MediaTransferProtocolManager* test_manager) {
 314   DCHECK(!media_transfer_protocol_manager_);
 315   media_transfer_protocol_manager_.reset(test_manager);
 316 }
 317
 318 void StorageMonitorLinux::EjectDevice(
 319     const std::string& device_id,
 320     base::Callback<void(EjectStatus)> callback) {
 321   StorageInfo::Type type;
 322   if (!StorageInfo::CrackDeviceId(device_id, &type, NULL)) {
 323     callback.Run(EJECT_FAILURE);
 324     return;
 325   }
 326
 327   if (type == StorageInfo::MTP_OR_PTP) {
 328     media_transfer_protocol_device_observer_->EjectDevice(device_id, callback);
 329     return;
 330   }
 331
 332   // Find the mount point for the given device ID.
 333   base::FilePath path;
 334   base::FilePath device;
 335   for (MountMap::iterator mount_info = mount_info_map_.begin();
 336        mount_info != mount_info_map_.end(); ++mount_info) {
 337     if (mount_info->second.storage_info.device_id() == device_id) {
 338       path = mount_info->first;
 339       device = mount_info->second.mount_device;
 340       mount_info_map_.erase(mount_info);
 341       break;
 342     }
 343   }
 344
 345   if (path.empty()) {
 346     callback.Run(EJECT_NO_SUCH_DEVICE);
 347     return;
 348   }
 349
 350   receiver()->ProcessDetach(device_id);
 351
 352   BrowserThread::PostTaskAndReplyWithResult(
 353       BrowserThread::FILE, FROM_HERE,
 354       base::Bind(&EjectPathOnFileThread, path, device),
 355       callback);
 356 }
 357
 358 void StorageMonitorLinux::OnMtabWatcherCreated(MtabWatcherLinux* watcher) {
 359   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 360   mtab_watcher_.reset(watcher);
 361 }
 362
 363 void StorageMonitorLinux::UpdateMtab(const MountPointDeviceMap& new_mtab) {
 364   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 365
 366   // Check existing mtab entries for unaccounted mount points.
 367   // These mount points must have been removed in the new mtab.
 368   std::list<base::FilePath> mount_points_to_erase;
 369   std::list<base::FilePath> multiple_mounted_devices_needing_reattachment;
 370   for (MountMap::const_iterator old_iter = mount_info_map_.begin();
 371        old_iter != mount_info_map_.end(); ++old_iter) {
 372     const base::FilePath& mount_point = old_iter->first;
 373     const base::FilePath& mount_device = old_iter->second.mount_device;
 374     MountPointDeviceMap::const_iterator new_iter = new_mtab.find(mount_point);
 375     // |mount_point| not in |new_mtab| or |mount_device| is no longer mounted at
 376     // |mount_point|.
 377     if (new_iter == new_mtab.end() || (new_iter->second != mount_device)) {
 378       MountPriorityMap::iterator priority =
 379           mount_priority_map_.find(mount_device);
 380       DCHECK(priority != mount_priority_map_.end());
 381       ReferencedMountPoint::const_iterator has_priority =
 382           priority->second.find(mount_point);
 383       if (StorageInfo::IsRemovableDevice(
 384               old_iter->second.storage_info.device_id())) {
 385         DCHECK(has_priority != priority->second.end());
 386         if (has_priority->second) {
 387           receiver()->ProcessDetach(old_iter->second.storage_info.device_id());
 388         }
 389         if (priority->second.size() > 1)
 390           multiple_mounted_devices_needing_reattachment.push_back(mount_device);
 391       }
 392       priority->second.erase(mount_point);
 393       if (priority->second.empty())
 394         mount_priority_map_.erase(mount_device);
 395       mount_points_to_erase.push_back(mount_point);
 396     }
 397   }
 398
 399   // Erase the |mount_info_map_| entries afterwards. Erasing in the loop above
 400   // using the iterator is slightly more efficient, but more tricky, since
 401   // calling std::map::erase() on an iterator invalidates it.
 402   for (std::list<base::FilePath>::const_iterator it =
 403            mount_points_to_erase.begin();
 404        it != mount_points_to_erase.end();
 405        ++it) {
 406     mount_info_map_.erase(*it);
 407   }
 408
 409   // For any multiply mounted device where the mount that we had notified
 410   // got detached, send a notification of attachment for one of the other
 411   // mount points.
 412   for (std::list<base::FilePath>::const_iterator it =
 413            multiple_mounted_devices_needing_reattachment.begin();
 414        it != multiple_mounted_devices_needing_reattachment.end();
 415        ++it) {
 416     ReferencedMountPoint::iterator first_mount_point_info =
 417         mount_priority_map_.find(*it)->second.begin();
 418     const base::FilePath& mount_point = first_mount_point_info->first;
 419     first_mount_point_info->second = true;
 420
 421     const StorageInfo& mount_info =
 422         mount_info_map_.find(mount_point)->second.storage_info;
 423     DCHECK(StorageInfo::IsRemovableDevice(mount_info.device_id()));
 424     receiver()->ProcessAttach(mount_info);
 425   }
 426
 427   // Check new mtab entries against existing ones.
 428   for (MountPointDeviceMap::const_iterator new_iter = new_mtab.begin();
 429        new_iter != new_mtab.end(); ++new_iter) {
 430     const base::FilePath& mount_point = new_iter->first;
 431     const base::FilePath& mount_device = new_iter->second;
 432     MountMap::iterator old_iter = mount_info_map_.find(mount_point);
 433     if (old_iter == mount_info_map_.end() ||
 434         old_iter->second.mount_device != mount_device) {
 435       // New mount point found or an existing mount point found with a new
 436       // device.
 437       if (IsDeviceAlreadyMounted(mount_device)) {
 438         HandleDeviceMountedMultipleTimes(mount_device, mount_point);
 439       } else {
 440         BrowserThread::PostTaskAndReplyWithResult(
 441             BrowserThread::FILE, FROM_HERE,
 442             base::Bind(get_device_info_callback_, mount_device, mount_point),
 443             base::Bind(&StorageMonitorLinux::AddNewMount,
 444                        weak_ptr_factory_.GetWeakPtr(),
 445                        mount_device));
 446       }
 447     }
 448   }
 449
 450   // Note: relies on scheduled tasks on the file thread being sequential. This
 451   // block needs to follow the for loop, so that the DoNothing call on the FILE
 452   // thread happens after the scheduled metadata retrievals, meaning that the
 453   // reply callback will then happen after all the AddNewMount calls.
 454   if (!IsInitialized()) {
 455     BrowserThread::PostTaskAndReply(
 456         BrowserThread::FILE, FROM_HERE,
 457         base::Bind(&base::DoNothing),
 458         base::Bind(&StorageMonitorLinux::MarkInitialized,
 459                    weak_ptr_factory_.GetWeakPtr()));
 460   }
 461 }
 462
 463 bool StorageMonitorLinux::IsDeviceAlreadyMounted(
 464     const base::FilePath& mount_device) const {
 465   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 466   return ContainsKey(mount_priority_map_, mount_device);
 467 }
 468
 469 void StorageMonitorLinux::HandleDeviceMountedMultipleTimes(
 470     const base::FilePath& mount_device,
 471     const base::FilePath& mount_point) {
 472   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 473
 474   MountPriorityMap::iterator priority = mount_priority_map_.find(mount_device);
 475   DCHECK(priority != mount_priority_map_.end());
 476   const base::FilePath& other_mount_point = priority->second.begin()->first;
 477   priority->second[mount_point] = false;
 478   mount_info_map_[mount_point] =
 479       mount_info_map_.find(other_mount_point)->second;
 480 }
 481
 482 void StorageMonitorLinux::AddNewMount(const base::FilePath& mount_device,
 483                                       scoped_ptr<StorageInfo> storage_info) {
 484   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 485
 486   if (!storage_info)
 487     return;
 488
 489   DCHECK(!storage_info->device_id().empty());
 490
 491   bool removable = StorageInfo::IsRemovableDevice(storage_info->device_id());
 492   const base::FilePath mount_point(storage_info->location());
 493
 494   MountPointInfo mount_point_info;
 495   mount_point_info.mount_device = mount_device;
 496   mount_point_info.storage_info = *storage_info;
 497   mount_info_map_[mount_point] = mount_point_info;
 498   mount_priority_map_[mount_device][mount_point] = removable;
 499   receiver()->ProcessAttach(*storage_info);
 500 }
 501
 502 StorageMonitor* StorageMonitor::CreateInternal() {
 503   const base::FilePath kDefaultMtabPath("/etc/mtab");
 504   return new StorageMonitorLinux(kDefaultMtabPath);
 505 }
 506
 507 }  // namespace storage_monitor