src/chrome/browser/chromeos/fileapi/file_system_backend.cc

   1 // Copyright 2013 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 "chrome/browser/chromeos/fileapi/file_system_backend.h"
   6
   7 #include "base/logging.h"
   8 #include "base/memory/scoped_ptr.h"
   9 #include "base/strings/stringprintf.h"
  10 #include "chrome/browser/chromeos/fileapi/file_access_permissions.h"
  11 #include "chrome/browser/chromeos/fileapi/file_system_backend_delegate.h"
  12 #include "chrome/browser/media_galleries/fileapi/media_file_system_backend.h"
  13 #include "chrome/common/url_constants.h"
  14 #include "chromeos/dbus/cros_disks_client.h"
  15 #include "storage/browser/blob/file_stream_reader.h"
  16 #include "storage/browser/fileapi/async_file_util.h"
  17 #include "storage/browser/fileapi/external_mount_points.h"
  18 #include "storage/browser/fileapi/file_stream_writer.h"
  19 #include "storage/browser/fileapi/file_system_context.h"
  20 #include "storage/browser/fileapi/file_system_operation.h"
  21 #include "storage/browser/fileapi/file_system_operation_context.h"
  22 #include "storage/browser/fileapi/file_system_url.h"
  23
  24 namespace chromeos {
  25
  26 // static
  27 bool FileSystemBackend::CanHandleURL(const storage::FileSystemURL& url) {
  28   if (!url.is_valid())
  29     return false;
  30   return url.type() == storage::kFileSystemTypeNativeLocal ||
  31          url.type() == storage::kFileSystemTypeRestrictedNativeLocal ||
  32          url.type() == storage::kFileSystemTypeDrive ||
  33          url.type() == storage::kFileSystemTypeProvided ||
  34          url.type() == storage::kFileSystemTypeDeviceMediaAsFileStorage;
  35 }
  36
  37 FileSystemBackend::FileSystemBackend(
  38     FileSystemBackendDelegate* drive_delegate,
  39     FileSystemBackendDelegate* file_system_provider_delegate,
  40     FileSystemBackendDelegate* mtp_delegate,
  41     scoped_refptr<storage::SpecialStoragePolicy> special_storage_policy,
  42     scoped_refptr<storage::ExternalMountPoints> mount_points,
  43     storage::ExternalMountPoints* system_mount_points)
  44     : special_storage_policy_(special_storage_policy),
  45       file_access_permissions_(new FileAccessPermissions()),
  46       local_file_util_(storage::AsyncFileUtil::CreateForLocalFileSystem()),
  47       drive_delegate_(drive_delegate),
  48       file_system_provider_delegate_(file_system_provider_delegate),
  49       mtp_delegate_(mtp_delegate),
  50       mount_points_(mount_points),
  51       system_mount_points_(system_mount_points) {
  52 }
  53
  54 FileSystemBackend::~FileSystemBackend() {
  55 }
  56
  57 void FileSystemBackend::AddSystemMountPoints() {
  58   // RegisterFileSystem() is no-op if the mount point with the same name
  59   // already exists, hence it's safe to call without checking if a mount
  60   // point already exists or not.
  61   system_mount_points_->RegisterFileSystem(
  62       "archive",
  63       storage::kFileSystemTypeNativeLocal,
  64       storage::FileSystemMountOption(),
  65       chromeos::CrosDisksClient::GetArchiveMountPoint());
  66   system_mount_points_->RegisterFileSystem(
  67       "removable",
  68       storage::kFileSystemTypeNativeLocal,
  69       storage::FileSystemMountOption(storage::COPY_SYNC_OPTION_SYNC),
  70       chromeos::CrosDisksClient::GetRemovableDiskMountPoint());
  71   system_mount_points_->RegisterFileSystem(
  72       "oem",
  73       storage::kFileSystemTypeRestrictedNativeLocal,
  74       storage::FileSystemMountOption(),
  75       base::FilePath(FILE_PATH_LITERAL("/usr/share/oem")));
  76 }
  77
  78 bool FileSystemBackend::CanHandleType(storage::FileSystemType type) const {
  79   switch (type) {
  80     case storage::kFileSystemTypeExternal:
  81     case storage::kFileSystemTypeDrive:
  82     case storage::kFileSystemTypeRestrictedNativeLocal:
  83     case storage::kFileSystemTypeNativeLocal:
  84     case storage::kFileSystemTypeNativeForPlatformApp:
  85     case storage::kFileSystemTypeDeviceMediaAsFileStorage:
  86     case storage::kFileSystemTypeProvided:
  87       return true;
  88     default:
  89       return false;
  90   }
  91 }
  92
  93 void FileSystemBackend::Initialize(storage::FileSystemContext* context) {
  94 }
  95
  96 void FileSystemBackend::ResolveURL(const storage::FileSystemURL& url,
  97                                    storage::OpenFileSystemMode mode,
  98                                    const OpenFileSystemCallback& callback) {
  99   std::string id;
 100   storage::FileSystemType type;
 101   std::string cracked_id;
 102   base::FilePath path;
 103   storage::FileSystemMountOption option;
 104   if (!mount_points_->CrackVirtualPath(
 105            url.virtual_path(), &id, &type, &cracked_id, &path, &option) &&
 106       !system_mount_points_->CrackVirtualPath(
 107            url.virtual_path(), &id, &type, &cracked_id, &path, &option)) {
 108     // Not under a mount point, so return an error, since the root is not
 109     // accessible.
 110     GURL root_url = GURL(storage::GetExternalFileSystemRootURIString(
 111         url.origin(), std::string()));
 112     callback.Run(root_url, std::string(), base::File::FILE_ERROR_SECURITY);
 113     return;
 114   }
 115
 116   std::string name;
 117   // Construct a URL restricted to the found mount point.
 118   std::string root_url =
 119       storage::GetExternalFileSystemRootURIString(url.origin(), id);
 120
 121   // For removable and archives, the file system root is the external mount
 122   // point plus the inner mount point.
 123   if (id == "archive" || id == "removable") {
 124     std::vector<std::string> components;
 125     url.virtual_path().GetComponents(&components);
 126     DCHECK_EQ(id, components.at(0));
 127     if (components.size() < 2) {
 128       // Unable to access /archive and /removable directories directly. The
 129       // inner mount name must be specified.
 130       callback.Run(
 131           GURL(root_url), std::string(), base::File::FILE_ERROR_SECURITY);
 132       return;
 133     }
 134     std::string inner_mount_name = components[1];
 135     root_url += inner_mount_name + "/";
 136     name = inner_mount_name;
 137   } else {
 138     name = id;
 139   }
 140
 141   callback.Run(GURL(root_url), name, base::File::FILE_OK);
 142 }
 143
 144 storage::FileSystemQuotaUtil* FileSystemBackend::GetQuotaUtil() {
 145   // No quota support.
 146   return NULL;
 147 }
 148
 149 const storage::UpdateObserverList* FileSystemBackend::GetUpdateObservers(
 150     storage::FileSystemType type) const {
 151   return NULL;
 152 }
 153
 154 const storage::ChangeObserverList* FileSystemBackend::GetChangeObservers(
 155     storage::FileSystemType type) const {
 156   return NULL;
 157 }
 158
 159 const storage::AccessObserverList* FileSystemBackend::GetAccessObservers(
 160     storage::FileSystemType type) const {
 161   return NULL;
 162 }
 163
 164 bool FileSystemBackend::IsAccessAllowed(
 165     const storage::FileSystemURL& url) const {
 166   if (!url.is_valid())
 167     return false;
 168
 169   // No extra check is needed for isolated file systems.
 170   if (url.mount_type() == storage::kFileSystemTypeIsolated)
 171     return true;
 172
 173   if (!CanHandleURL(url))
 174     return false;
 175
 176   std::string extension_id = url.origin().host();
 177   // TODO(mtomasz): Temporarily whitelist TimeScapes. Remove this in M-31.
 178   // See: crbug.com/271946
 179   if (extension_id == "mlbmkoenclnokonejhlfakkeabdlmpek" &&
 180       url.type() == storage::kFileSystemTypeRestrictedNativeLocal) {
 181     return true;
 182   }
 183
 184   // Grant access for URL having "externalfile:" scheme. The URL
 185   // filesystem:externalfile:/xxx cannot be parsed directly. The URL is created
 186   // only by DriveURLRequestJob.
 187   if (url.origin().scheme() == chrome::kExternalFileScheme)
 188     return true;
 189
 190   // Check first to make sure this extension has fileBrowserHander permissions.
 191   if (!special_storage_policy_.get() ||
 192       !special_storage_policy_->IsFileHandler(extension_id))
 193     return false;
 194
 195   return file_access_permissions_->HasAccessPermission(extension_id,
 196                                                        url.virtual_path());
 197 }
 198
 199 void FileSystemBackend::GrantFullAccessToExtension(
 200     const std::string& extension_id) {
 201   if (!special_storage_policy_.get())
 202     return;
 203   if (!special_storage_policy_->IsFileHandler(extension_id)) {
 204     NOTREACHED();
 205     return;
 206   }
 207   file_access_permissions_->GrantFullAccessPermission(extension_id);
 208 }
 209
 210 void FileSystemBackend::GrantFileAccessToExtension(
 211     const std::string& extension_id, const base::FilePath& virtual_path) {
 212   if (!special_storage_policy_.get())
 213     return;
 214   // All we care about here is access from extensions for now.
 215   if (!special_storage_policy_->IsFileHandler(extension_id)) {
 216     NOTREACHED();
 217     return;
 218   }
 219
 220   std::string id;
 221   storage::FileSystemType type;
 222   std::string cracked_id;
 223   base::FilePath path;
 224   storage::FileSystemMountOption option;
 225   if (!mount_points_->CrackVirtualPath(virtual_path, &id, &type, &cracked_id,
 226                                        &path, &option) &&
 227       !system_mount_points_->CrackVirtualPath(virtual_path, &id, &type,
 228                                               &cracked_id, &path, &option)) {
 229     return;
 230   }
 231
 232   if (type == storage::kFileSystemTypeRestrictedNativeLocal) {
 233     LOG(ERROR) << "Can't grant access for restricted mount point";
 234     return;
 235   }
 236
 237   file_access_permissions_->GrantAccessPermission(extension_id, virtual_path);
 238 }
 239
 240 void FileSystemBackend::RevokeAccessForExtension(
 241       const std::string& extension_id) {
 242   file_access_permissions_->RevokePermissions(extension_id);
 243 }
 244
 245 std::vector<base::FilePath> FileSystemBackend::GetRootDirectories() const {
 246   std::vector<storage::MountPoints::MountPointInfo> mount_points;
 247   mount_points_->AddMountPointInfosTo(&mount_points);
 248   system_mount_points_->AddMountPointInfosTo(&mount_points);
 249
 250   std::vector<base::FilePath> root_dirs;
 251   for (size_t i = 0; i < mount_points.size(); ++i)
 252     root_dirs.push_back(mount_points[i].path);
 253   return root_dirs;
 254 }
 255
 256 storage::AsyncFileUtil* FileSystemBackend::GetAsyncFileUtil(
 257     storage::FileSystemType type) {
 258   switch (type) {
 259     case storage::kFileSystemTypeDrive:
 260       return drive_delegate_->GetAsyncFileUtil(type);
 261     case storage::kFileSystemTypeProvided:
 262       return file_system_provider_delegate_->GetAsyncFileUtil(type);
 263     case storage::kFileSystemTypeNativeLocal:
 264     case storage::kFileSystemTypeRestrictedNativeLocal:
 265       return local_file_util_.get();
 266     case storage::kFileSystemTypeDeviceMediaAsFileStorage:
 267       return mtp_delegate_->GetAsyncFileUtil(type);
 268     default:
 269       NOTREACHED();
 270   }
 271   return NULL;
 272 }
 273
 274 storage::WatcherManager* FileSystemBackend::GetWatcherManager(
 275     storage::FileSystemType type) {
 276   return NULL;
 277 }
 278
 279 storage::CopyOrMoveFileValidatorFactory*
 280 FileSystemBackend::GetCopyOrMoveFileValidatorFactory(
 281     storage::FileSystemType type,
 282     base::File::Error* error_code) {
 283   DCHECK(error_code);
 284   *error_code = base::File::FILE_OK;
 285   return NULL;
 286 }
 287
 288 storage::FileSystemOperation* FileSystemBackend::CreateFileSystemOperation(
 289     const storage::FileSystemURL& url,
 290     storage::FileSystemContext* context,
 291     base::File::Error* error_code) const {
 292   DCHECK(url.is_valid());
 293
 294   if (!IsAccessAllowed(url)) {
 295     *error_code = base::File::FILE_ERROR_SECURITY;
 296     return NULL;
 297   }
 298
 299   if (url.type() == storage::kFileSystemTypeDeviceMediaAsFileStorage) {
 300     // MTP file operations run on MediaTaskRunner.
 301     return storage::FileSystemOperation::Create(
 302         url,
 303         context,
 304         make_scoped_ptr(new storage::FileSystemOperationContext(
 305             context, MediaFileSystemBackend::MediaTaskRunner().get())));
 306   }
 307
 308   DCHECK(url.type() == storage::kFileSystemTypeNativeLocal ||
 309          url.type() == storage::kFileSystemTypeRestrictedNativeLocal ||
 310          url.type() == storage::kFileSystemTypeDrive ||
 311          url.type() == storage::kFileSystemTypeProvided);
 312   return storage::FileSystemOperation::Create(
 313       url,
 314       context,
 315       make_scoped_ptr(new storage::FileSystemOperationContext(context)));
 316 }
 317
 318 bool FileSystemBackend::SupportsStreaming(
 319     const storage::FileSystemURL& url) const {
 320   return url.type() == storage::kFileSystemTypeDrive ||
 321          url.type() == storage::kFileSystemTypeProvided ||
 322          url.type() == storage::kFileSystemTypeDeviceMediaAsFileStorage;
 323 }
 324
 325 bool FileSystemBackend::HasInplaceCopyImplementation(
 326     storage::FileSystemType type) const {
 327   switch (type) {
 328     case storage::kFileSystemTypeDrive:
 329     case storage::kFileSystemTypeProvided:
 330     case storage::kFileSystemTypeDeviceMediaAsFileStorage:
 331       return true;
 332     case storage::kFileSystemTypeNativeLocal:
 333     case storage::kFileSystemTypeRestrictedNativeLocal:
 334       return false;
 335     default:
 336       NOTREACHED();
 337   }
 338   return true;
 339 }
 340
 341 scoped_ptr<storage::FileStreamReader> FileSystemBackend::CreateFileStreamReader(
 342     const storage::FileSystemURL& url,
 343     int64 offset,
 344     int64 max_bytes_to_read,
 345     const base::Time& expected_modification_time,
 346     storage::FileSystemContext* context) const {
 347   DCHECK(url.is_valid());
 348
 349   if (!IsAccessAllowed(url))
 350     return scoped_ptr<storage::FileStreamReader>();
 351
 352   switch (url.type()) {
 353     case storage::kFileSystemTypeDrive:
 354       return drive_delegate_->CreateFileStreamReader(
 355           url, offset, max_bytes_to_read, expected_modification_time, context);
 356     case storage::kFileSystemTypeProvided:
 357       return file_system_provider_delegate_->CreateFileStreamReader(
 358           url, offset, max_bytes_to_read, expected_modification_time, context);
 359     case storage::kFileSystemTypeNativeLocal:
 360     case storage::kFileSystemTypeRestrictedNativeLocal:
 361       return scoped_ptr<storage::FileStreamReader>(
 362           storage::FileStreamReader::CreateForFileSystemFile(
 363               context, url, offset, expected_modification_time));
 364     case storage::kFileSystemTypeDeviceMediaAsFileStorage:
 365       return mtp_delegate_->CreateFileStreamReader(
 366           url, offset, max_bytes_to_read, expected_modification_time, context);
 367     default:
 368       NOTREACHED();
 369   }
 370   return scoped_ptr<storage::FileStreamReader>();
 371 }
 372
 373 scoped_ptr<storage::FileStreamWriter> FileSystemBackend::CreateFileStreamWriter(
 374     const storage::FileSystemURL& url,
 375     int64 offset,
 376     storage::FileSystemContext* context) const {
 377   DCHECK(url.is_valid());
 378
 379   if (!IsAccessAllowed(url))
 380     return scoped_ptr<storage::FileStreamWriter>();
 381
 382   switch (url.type()) {
 383     case storage::kFileSystemTypeDrive:
 384       return drive_delegate_->CreateFileStreamWriter(url, offset, context);
 385     case storage::kFileSystemTypeProvided:
 386       return file_system_provider_delegate_->CreateFileStreamWriter(
 387           url, offset, context);
 388     case storage::kFileSystemTypeNativeLocal:
 389       return scoped_ptr<storage::FileStreamWriter>(
 390           storage::FileStreamWriter::CreateForLocalFile(
 391               context->default_file_task_runner(),
 392               url.path(),
 393               offset,
 394               storage::FileStreamWriter::OPEN_EXISTING_FILE));
 395     case storage::kFileSystemTypeRestrictedNativeLocal:
 396       // Restricted native local file system is read only.
 397       return scoped_ptr<storage::FileStreamWriter>();
 398     case storage::kFileSystemTypeDeviceMediaAsFileStorage:
 399       return mtp_delegate_->CreateFileStreamWriter(url, offset, context);
 400     default:
 401       NOTREACHED();
 402   }
 403   return scoped_ptr<storage::FileStreamWriter>();
 404 }
 405
 406 bool FileSystemBackend::GetVirtualPath(
 407     const base::FilePath& filesystem_path,
 408     base::FilePath* virtual_path) {
 409   return mount_points_->GetVirtualPath(filesystem_path, virtual_path) ||
 410          system_mount_points_->GetVirtualPath(filesystem_path, virtual_path);
 411 }
 412
 413 void FileSystemBackend::GetRedirectURLForContents(
 414     const storage::FileSystemURL& url,
 415     const storage::URLCallback& callback) {
 416   DCHECK(url.is_valid());
 417
 418   if (!IsAccessAllowed(url))
 419     return callback.Run(GURL());
 420
 421   switch (url.type()) {
 422     case storage::kFileSystemTypeDrive:
 423       drive_delegate_->GetRedirectURLForContents(url, callback);
 424       return;
 425     case storage::kFileSystemTypeProvided:
 426       file_system_provider_delegate_->GetRedirectURLForContents(url,
 427                                                                   callback);
 428       return;
 429     case storage::kFileSystemTypeDeviceMediaAsFileStorage:
 430       mtp_delegate_->GetRedirectURLForContents(url, callback);
 431       return;
 432     case storage::kFileSystemTypeNativeLocal:
 433     case storage::kFileSystemTypeRestrictedNativeLocal:
 434       callback.Run(GURL());
 435       return;
 436     default:
 437       NOTREACHED();
 438   }
 439   callback.Run(GURL());
 440 }
 441
 442 }  // namespace chromeos