1 /*
2  * Copyright (C) 2022 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #pragma once
18 
19 #include <string>
20 
21 #include <fstab/fstab.h>
22 
23 constexpr char kOverlayfsFileContext[] = "u:object_r:overlayfs_file:s0";
24 
25 constexpr char kScratchMountPoint[] = "/mnt/scratch";
26 constexpr char kOverlayTopDir[] = "overlay";
27 constexpr char kUpperName[] = "upper";
28 constexpr char kWorkName[] = "work";
29 
30 #if ALLOW_ADBD_DISABLE_VERITY
31 constexpr bool kAllowOverlayfs = true;
32 #else
33 constexpr bool kAllowOverlayfs = false;
34 #endif
35 
36 class AutoSetFsCreateCon final {
37   public:
AutoSetFsCreateCon()38     AutoSetFsCreateCon() {}
AutoSetFsCreateCon(const std::string & context)39     AutoSetFsCreateCon(const std::string& context) { Set(context); }
~AutoSetFsCreateCon()40     ~AutoSetFsCreateCon() { Restore(); }
41 
Ok()42     bool Ok() const { return ok_; }
43     bool Set(const std::string& context);
44     bool Restore();
45 
46   private:
47     bool ok_ = false;
48     bool restored_ = false;
49 };
50 
51 bool fs_mgr_is_dsu_running();
52 bool fs_mgr_filesystem_has_space(const std::string& mount_point);
53 const std::string fs_mgr_mount_point(const std::string& mount_point);
54 bool OverlayfsSetupAllowed(bool verbose = false);
55 bool MountScratch(const std::string& device_path, bool readonly = false);
56 bool fs_mgr_overlayfs_umount_scratch();
57 std::vector<const std::string> OverlayMountPoints();
58 bool fs_mgr_overlayfs_already_mounted(const std::string& mount_point, bool overlay_only = true);
59 bool fs_mgr_wants_overlayfs(android::fs_mgr::FstabEntry* entry);
60 android::fs_mgr::Fstab fs_mgr_overlayfs_candidate_list(const android::fs_mgr::Fstab& fstab);
61 std::string GetEncodedBaseDirForMountPoint(const std::string& mount_point);
62