OLD | NEW |
1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. | 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 | 2 // Use of this source code is governed by a BSD-style license that can be |
3 // found in the LICENSE file. | 3 // found in the LICENSE file. |
4 | 4 |
5 #ifndef WEBKIT_BROWSER_FILEAPI_ISOLATED_CONTEXT_H_ | 5 #include "storage/browser/fileapi/isolated_context.h" |
6 #define WEBKIT_BROWSER_FILEAPI_ISOLATED_CONTEXT_H_ | |
7 | |
8 #include <map> | |
9 #include <set> | |
10 #include <string> | |
11 #include <vector> | |
12 | |
13 #include "base/basictypes.h" | |
14 #include "base/files/file_path.h" | |
15 #include "base/lazy_instance.h" | |
16 #include "base/memory/singleton.h" | |
17 #include "base/synchronization/lock.h" | |
18 #include "webkit/browser/fileapi/mount_points.h" | |
19 #include "webkit/browser/storage_browser_export.h" | |
20 #include "webkit/common/fileapi/file_system_types.h" | |
21 | |
22 namespace storage { | |
23 class FileSystemURL; | |
24 } | |
25 | |
26 namespace storage { | |
27 | |
28 // Manages isolated filesystem mount points which have no well-known names | |
29 // and are identified by a string 'filesystem ID', which usually just looks | |
30 // like random value. | |
31 // This type of filesystem can be created on the fly and may go away when it has | |
32 // no references from renderers. | |
33 // Files in an isolated filesystem are registered with corresponding names and | |
34 // identified by a filesystem URL like: | |
35 // | |
36 // filesystem:<origin>/isolated/<filesystem_id>/<name>/relative/path | |
37 // | |
38 // Some methods of this class are virtual just for mocking. | |
39 // | |
40 class STORAGE_EXPORT IsolatedContext : public MountPoints { | |
41 public: | |
42 class STORAGE_EXPORT FileInfoSet { | |
43 public: | |
44 FileInfoSet(); | |
45 ~FileInfoSet(); | |
46 | |
47 // Add the given |path| to the set and populates |registered_name| with | |
48 // the registered name assigned for the path. |path| needs to be | |
49 // absolute and should not contain parent references. | |
50 // Return false if the |path| is not valid and could not be added. | |
51 bool AddPath(const base::FilePath& path, std::string* registered_name); | |
52 | |
53 // Add the given |path| with the |name|. | |
54 // Return false if the |name| is already registered in the set or | |
55 // is not valid and could not be added. | |
56 bool AddPathWithName(const base::FilePath& path, const std::string& name); | |
57 | |
58 const std::set<MountPointInfo>& fileset() const { return fileset_; } | |
59 | |
60 private: | |
61 std::set<MountPointInfo> fileset_; | |
62 }; | |
63 | |
64 // The instance is lazily created per browser process. | |
65 static IsolatedContext* GetInstance(); | |
66 | |
67 // Returns true if the given filesystem type is managed by IsolatedContext | |
68 // (i.e. if the given |type| is Isolated or External). | |
69 // TODO(kinuko): needs a better function name. | |
70 static bool IsIsolatedType(FileSystemType type); | |
71 | |
72 // Registers a new isolated filesystem with the given FileInfoSet |files| | |
73 // and returns the new filesystem_id. The files are registered with their | |
74 // register_name as their keys so that later we can resolve the full paths | |
75 // for the given name. We only expose the name and the ID for the | |
76 // newly created filesystem to the renderer for the sake of security. | |
77 // | |
78 // The renderer will be sending filesystem requests with a virtual path like | |
79 // '/<filesystem_id>/<registered_name>/<relative_path_from_the_dropped_path>' | |
80 // for which we could crack in the browser process by calling | |
81 // CrackIsolatedPath to get the full path. | |
82 // | |
83 // For example: if a dropped file has a path like '/a/b/foo' and we register | |
84 // the path with the name 'foo' in the newly created filesystem. | |
85 // Later if the context is asked to crack a virtual path like '/<fsid>/foo' | |
86 // it can properly return the original path '/a/b/foo' by looking up the | |
87 // internal mapping. Similarly if a dropped entry is a directory and its | |
88 // path is like '/a/b/dir' a virtual path like '/<fsid>/dir/foo' can be | |
89 // cracked into '/a/b/dir/foo'. | |
90 // | |
91 // Note that the path in |fileset| that contains '..' or is not an | |
92 // absolute path is skipped and is not registered. | |
93 std::string RegisterDraggedFileSystem(const FileInfoSet& files); | |
94 | |
95 // Registers a new isolated filesystem for a given |path| of filesystem | |
96 // |type| filesystem with |filesystem_id| and returns a new filesystem ID. | |
97 // |path| must be an absolute path which has no parent references ('..'). | |
98 // If |register_name| is non-null and has non-empty string the path is | |
99 // registered as the given |register_name|, otherwise it is populated | |
100 // with the name internally assigned to the path. | |
101 std::string RegisterFileSystemForPath(FileSystemType type, | |
102 const std::string& filesystem_id, | |
103 const base::FilePath& path, | |
104 std::string* register_name); | |
105 | |
106 // Registers a virtual filesystem. This is different from | |
107 // RegisterFileSystemForPath because register_name is required, and | |
108 // cracked_path_prefix is allowed to be non-absolute. | |
109 // |register_name| is required, since we cannot infer one from the path. | |
110 // |cracked_path_prefix| has no parent references, but can be relative. | |
111 std::string RegisterFileSystemForVirtualPath( | |
112 FileSystemType type, | |
113 const std::string& register_name, | |
114 const base::FilePath& cracked_path_prefix); | |
115 | |
116 // Revokes all filesystem(s) registered for the given path. | |
117 // This is assumed to be called when the registered path becomes | |
118 // globally invalid, e.g. when a device for the path is detached. | |
119 // | |
120 // Note that this revokes the filesystem no matter how many references it has. | |
121 // It is ok to call this for the path that has no associated filesystems. | |
122 // Note that this only works for the filesystems registered by | |
123 // |RegisterFileSystemForPath|. | |
124 void RevokeFileSystemByPath(const base::FilePath& path); | |
125 | |
126 // Adds a reference to a filesystem specified by the given filesystem_id. | |
127 void AddReference(const std::string& filesystem_id); | |
128 | |
129 // Removes a reference to a filesystem specified by the given filesystem_id. | |
130 // If the reference count reaches 0 the isolated context gets destroyed. | |
131 // It is OK to call this on the filesystem that has been already deleted | |
132 // (e.g. by RevokeFileSystemByPath). | |
133 void RemoveReference(const std::string& filesystem_id); | |
134 | |
135 // Returns a set of dragged MountPointInfos registered for the | |
136 // |filesystem_id|. | |
137 // The filesystem_id must be pointing to a dragged file system | |
138 // (i.e. must be the one registered by RegisterDraggedFileSystem). | |
139 // Returns false if the |filesystem_id| is not valid. | |
140 bool GetDraggedFileInfo(const std::string& filesystem_id, | |
141 std::vector<MountPointInfo>* files) const; | |
142 | |
143 // MountPoints overrides. | |
144 virtual bool HandlesFileSystemMountType(FileSystemType type) const OVERRIDE; | |
145 virtual bool RevokeFileSystem(const std::string& filesystem_id) OVERRIDE; | |
146 virtual bool GetRegisteredPath(const std::string& filesystem_id, | |
147 base::FilePath* path) const OVERRIDE; | |
148 virtual bool CrackVirtualPath( | |
149 const base::FilePath& virtual_path, | |
150 std::string* filesystem_id, | |
151 FileSystemType* type, | |
152 std::string* cracked_id, | |
153 base::FilePath* path, | |
154 FileSystemMountOption* mount_option) const OVERRIDE; | |
155 virtual FileSystemURL CrackURL(const GURL& url) const OVERRIDE; | |
156 virtual FileSystemURL CreateCrackedFileSystemURL( | |
157 const GURL& origin, | |
158 FileSystemType type, | |
159 const base::FilePath& path) const OVERRIDE; | |
160 | |
161 // Returns the virtual root path that looks like /<filesystem_id>. | |
162 base::FilePath CreateVirtualRootPath(const std::string& filesystem_id) const; | |
163 | |
164 private: | |
165 friend struct base::DefaultLazyInstanceTraits<IsolatedContext>; | |
166 | |
167 // Represents each file system instance (defined in the .cc). | |
168 class Instance; | |
169 | |
170 typedef std::map<std::string, Instance*> IDToInstance; | |
171 | |
172 // Reverse map from registered path to IDs. | |
173 typedef std::map<base::FilePath, std::set<std::string> > PathToID; | |
174 | |
175 // Obtain an instance of this class via GetInstance(). | |
176 IsolatedContext(); | |
177 virtual ~IsolatedContext(); | |
178 | |
179 // MountPoints overrides. | |
180 virtual FileSystemURL CrackFileSystemURL( | |
181 const FileSystemURL& url) const OVERRIDE; | |
182 | |
183 // Unregisters a file system of given |filesystem_id|. Must be called with | |
184 // lock_ held. Returns true if the file system is unregistered. | |
185 bool UnregisterFileSystem(const std::string& filesystem_id); | |
186 | |
187 // Returns a new filesystem_id. Called with lock. | |
188 std::string GetNewFileSystemId() const; | |
189 | |
190 // This lock needs to be obtained when accessing the instance_map_. | |
191 mutable base::Lock lock_; | |
192 | |
193 IDToInstance instance_map_; | |
194 PathToID path_to_id_map_; | |
195 | |
196 DISALLOW_COPY_AND_ASSIGN(IsolatedContext); | |
197 }; | |
198 | |
199 } // namespace storage | |
200 | |
201 #endif // WEBKIT_BROWSER_FILEAPI_ISOLATED_CONTEXT_H_ | |
OLD | NEW |