blob: b8b1a4af869c53ec9a02801222af20255b8795b2 [file] [log] [blame]
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef STORAGE_BROWSER_FILEAPI_OBFUSCATED_FILE_UTIL_H_
#define STORAGE_BROWSER_FILEAPI_OBFUSCATED_FILE_UTIL_H_
#include <map>
#include <set>
#include <string>
#include <vector>
#include "base/callback_forward.h"
#include "base/files/file.h"
#include "base/files/file_path.h"
#include "base/files/file_util_proxy.h"
#include "base/gtest_prod_util.h"
#include "base/memory/scoped_ptr.h"
#include "storage/browser/blob/shareable_file_reference.h"
#include "storage/browser/fileapi/file_system_file_util.h"
#include "storage/browser/fileapi/file_system_url.h"
#include "storage/browser/fileapi/sandbox_directory_database.h"
#include "storage/browser/fileapi/sandbox_file_system_backend_delegate.h"
#include "storage/browser/storage_browser_export.h"
#include "storage/common/fileapi/file_system_types.h"
namespace base {
class SequencedTaskRunner;
class TimeTicks;
}
namespace content {
class ObfuscatedFileUtilTest;
class QuotaBackendImplTest;
}
namespace storage {
class SpecialStoragePolicy;
}
class GURL;
namespace storage {
class FileSystemOperationContext;
class SandboxOriginDatabaseInterface;
class TimedTaskHelper;
// This file util stores directory information in LevelDB to obfuscate
// and to neutralize virtual file paths given by arbitrary apps.
// Files are stored with two-level isolation: per-origin and per-type.
// The isolation is done by storing data in separate directory partitions.
// For example, a file in Temporary file system for origin 'www.example.com'
// is stored in a different partition for a file in Persistent file system
// for the same origin, or for Temporary file system for another origin.
//
// * Per-origin directory name information is stored in a separate LevelDB,
// which is maintained by SandboxOriginDatabase.
// * Per-type directory name information is given by
// GetTypeStringForURLCallback that is given in CTOR.
// We use a small static mapping (e.g. 't' for Temporary type) for
// regular sandbox filesystems.
//
// The overall implementation philosophy of this class is that partial failures
// should leave us with an intact database; we'd prefer to leak the occasional
// backing file than have a database entry whose backing file is missing. When
// doing FSCK operations, if you find a loose backing file with no reference,
// you may safely delete it.
//
// This class must be deleted on the FILE thread, because that's where
// DropDatabases needs to be called.
class STORAGE_EXPORT_PRIVATE ObfuscatedFileUtil
: public FileSystemFileUtil {
public:
// Origin enumerator interface.
// An instance of this interface is assumed to be called on the file thread.
class AbstractOriginEnumerator {
public:
virtual ~AbstractOriginEnumerator() {}
// Returns the next origin. Returns empty if there are no more origins.
virtual GURL Next() = 0;
// Returns the current origin's information.
// |type_string| must be ascii string.
virtual bool HasTypeDirectory(const std::string& type_string) const = 0;
};
typedef base::Callback<std::string(const FileSystemURL&)>
GetTypeStringForURLCallback;
// |get_type_string_for_url| is user-defined callback that should return
// a type string for the given FileSystemURL. The type string is used
// to provide per-type isolation in the sandboxed filesystem directory.
// Note that this method is called on file_task_runner.
//
// |known_type_strings| are known type string names that this file system
// should care about.
// This info is used to determine whether we could delete the entire
// origin directory or not in DeleteDirectoryForOriginAndType. If no directory
// for any known type exists the origin directory may get deleted when
// one origin/type pair is deleted.
//
ObfuscatedFileUtil(storage::SpecialStoragePolicy* special_storage_policy,
const base::FilePath& file_system_directory,
leveldb::Env* env_override,
base::SequencedTaskRunner* file_task_runner,
const GetTypeStringForURLCallback& get_type_string_for_url,
const std::set<std::string>& known_type_strings,
SandboxFileSystemBackendDelegate* sandbox_delegate);
~ObfuscatedFileUtil() override;
// FileSystemFileUtil overrides.
base::File CreateOrOpen(FileSystemOperationContext* context,
const FileSystemURL& url,
int file_flags) override;
base::File::Error EnsureFileExists(FileSystemOperationContext* context,
const FileSystemURL& url,
bool* created) override;
base::File::Error CreateDirectory(FileSystemOperationContext* context,
const FileSystemURL& url,
bool exclusive,
bool recursive) override;
base::File::Error GetFileInfo(FileSystemOperationContext* context,
const FileSystemURL& url,
base::File::Info* file_info,
base::FilePath* platform_file) override;
scoped_ptr<AbstractFileEnumerator> CreateFileEnumerator(
FileSystemOperationContext* context,
const FileSystemURL& root_url) override;
base::File::Error GetLocalFilePath(FileSystemOperationContext* context,
const FileSystemURL& file_system_url,
base::FilePath* local_path) override;
base::File::Error Touch(FileSystemOperationContext* context,
const FileSystemURL& url,
const base::Time& last_access_time,
const base::Time& last_modified_time) override;
base::File::Error Truncate(FileSystemOperationContext* context,
const FileSystemURL& url,
int64 length) override;
base::File::Error CopyOrMoveFile(FileSystemOperationContext* context,
const FileSystemURL& src_url,
const FileSystemURL& dest_url,
CopyOrMoveOption option,
bool copy) override;
base::File::Error CopyInForeignFile(FileSystemOperationContext* context,
const base::FilePath& src_file_path,
const FileSystemURL& dest_url) override;
base::File::Error DeleteFile(FileSystemOperationContext* context,
const FileSystemURL& url) override;
base::File::Error DeleteDirectory(FileSystemOperationContext* context,
const FileSystemURL& url) override;
storage::ScopedFile CreateSnapshotFile(
FileSystemOperationContext* context,
const FileSystemURL& url,
base::File::Error* error,
base::File::Info* file_info,
base::FilePath* platform_path) override;
// Same as the other CreateFileEnumerator, but with recursive support.
scoped_ptr<AbstractFileEnumerator> CreateFileEnumerator(
FileSystemOperationContext* context,
const FileSystemURL& root_url,
bool recursive);
// Returns true if the directory |url| is empty.
bool IsDirectoryEmpty(
FileSystemOperationContext* context,
const FileSystemURL& url);
// Gets the topmost directory specific to this origin and type. This will
// contain both the directory database's files and all the backing file
// subdirectories.
// Returns the topmost origin directory if |type_string| is empty.
// Returns an empty path if the directory is undefined.
// If the directory is defined, it will be returned, even if
// there is a file system error (e.g. the directory doesn't exist on disk and
// |create| is false). Callers should always check |error_code| to make sure
// the returned path is usable.
base::FilePath GetDirectoryForOriginAndType(
const GURL& origin,
const std::string& type_string,
bool create,
base::File::Error* error_code);
// Deletes the topmost directory specific to this origin and type. This will
// delete its directory database.
// Deletes the topmost origin directory if |type_string| is empty.
bool DeleteDirectoryForOriginAndType(
const GURL& origin,
const std::string& type_string);
// Frees resources used by an origin's filesystem.
void CloseFileSystemForOriginAndType(const GURL& origin,
const std::string& type_string);
// This method and all methods of its returned class must be called only on
// the FILE thread. The caller is responsible for deleting the returned
// object.
AbstractOriginEnumerator* CreateOriginEnumerator();
// Deletes a directory database from the database list in the ObfuscatedFSFU
// and destroys the database on the disk.
void DestroyDirectoryDatabase(const GURL& origin,
const std::string& type_string);
// Computes a cost for storing a given file in the obfuscated FSFU.
// As the cost of a file is independent of the cost of its parent directories,
// this ignores all but the BaseName of the supplied path. In order to
// compute the cost of adding a multi-segment directory recursively, call this
// on each path segment and add the results.
static int64 ComputeFilePathCost(const base::FilePath& path);
// Tries to prepopulate directory database for the given type strings.
// This tries from the first one in the given type_strings and stops
// once it succeeds to do so for one database (i.e. it prepopulates
// at most one database).
void MaybePrepopulateDatabase(
const std::vector<std::string>& type_strings_to_prepopulate);
private:
typedef SandboxDirectoryDatabase::FileId FileId;
typedef SandboxDirectoryDatabase::FileInfo FileInfo;
friend class ObfuscatedFileEnumerator;
friend class content::ObfuscatedFileUtilTest;
friend class content::QuotaBackendImplTest;
// Helper method to create an obfuscated file util for regular
// (temporary, persistent) file systems. Used only for testing.
// Note: this is implemented in sandbox_file_system_backend_delegate.cc.
static ObfuscatedFileUtil* CreateForTesting(
storage::SpecialStoragePolicy* special_storage_policy,
const base::FilePath& file_system_directory,
leveldb::Env* env_override,
base::SequencedTaskRunner* file_task_runner);
base::FilePath GetDirectoryForURL(
const FileSystemURL& url,
bool create,
base::File::Error* error_code);
// This just calls get_type_string_for_url_ callback that is given in ctor.
std::string CallGetTypeStringForURL(const FileSystemURL& url);
base::File::Error GetFileInfoInternal(
SandboxDirectoryDatabase* db,
FileSystemOperationContext* context,
const FileSystemURL& url,
FileId file_id,
FileInfo* local_info,
base::File::Info* file_info,
base::FilePath* platform_file_path);
// Creates a new file, both the underlying backing file and the entry in the
// database. |dest_file_info| is an in-out parameter. Supply the name and
// parent_id; data_path is ignored. On success, data_path will
// always be set to the relative path [from the root of the type-specific
// filesystem directory] of a NEW backing file. Returns the new file.
base::File CreateAndOpenFile(
FileSystemOperationContext* context,
const FileSystemURL& dest_url,
FileInfo* dest_file_info,
int file_flags);
// The same as CreateAndOpenFile except that a file is not returned and if a
// path is provided in |source_path|, it will be used as a source from which
// to COPY data.
base::File::Error CreateFile(
FileSystemOperationContext* context,
const base::FilePath& source_file_path,
const FileSystemURL& dest_url,
FileInfo* dest_file_info);
// Updates |db| and |dest_file_info| at the end of creating a new file.
base::File::Error CommitCreateFile(
const base::FilePath& root,
const base::FilePath& local_path,
SandboxDirectoryDatabase* db,
FileInfo* dest_file_info);
// This converts from a relative path [as is stored in the FileInfo.data_path
// field] to an absolute platform path that can be given to the native
// filesystem.
base::FilePath DataPathToLocalPath(
const FileSystemURL& url,
const base::FilePath& data_file_path);
std::string GetDirectoryDatabaseKey(const GURL& origin,
const std::string& type_string);
// This returns NULL if |create| flag is false and a filesystem does not
// exist for the given |url|.
// For read operations |create| should be false.
SandboxDirectoryDatabase* GetDirectoryDatabase(const FileSystemURL& url,
bool create);
// Gets the topmost directory specific to this origin. This will
// contain both the filesystem type subdirectories.
base::FilePath GetDirectoryForOrigin(const GURL& origin,
bool create,
base::File::Error* error_code);
void InvalidateUsageCache(FileSystemOperationContext* context,
const GURL& origin,
FileSystemType type);
void MarkUsed();
void DropDatabases();
// Initializes the origin database. |origin_hint| may be used as a hint
// for initializing database if it's not empty.
bool InitOriginDatabase(const GURL& origin_hint, bool create);
base::File::Error GenerateNewLocalPath(
SandboxDirectoryDatabase* db,
FileSystemOperationContext* context,
const FileSystemURL& url,
base::FilePath* root,
base::FilePath* local_path);
base::File CreateOrOpenInternal(
FileSystemOperationContext* context,
const FileSystemURL& url,
int file_flags);
bool HasIsolatedStorage(const GURL& origin);
typedef std::map<std::string, SandboxDirectoryDatabase*> DirectoryMap;
DirectoryMap directories_;
scoped_ptr<SandboxOriginDatabaseInterface> origin_database_;
scoped_refptr<storage::SpecialStoragePolicy> special_storage_policy_;
base::FilePath file_system_directory_;
leveldb::Env* env_override_;
// Used to delete database after a certain period of inactivity.
int64 db_flush_delay_seconds_;
scoped_refptr<base::SequencedTaskRunner> file_task_runner_;
scoped_ptr<TimedTaskHelper> timer_;
GetTypeStringForURLCallback get_type_string_for_url_;
std::set<std::string> known_type_strings_;
// Not owned.
SandboxFileSystemBackendDelegate* sandbox_delegate_;
DISALLOW_COPY_AND_ASSIGN(ObfuscatedFileUtil);
};
} // namespace storage
#endif // STORAGE_BROWSER_FILEAPI_OBFUSCATED_FILE_UTIL_H_