1 /*
2  * Copyright (C) 2015 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 #ifndef ANDROID_VOLD_UTILS_H
18 #define ANDROID_VOLD_UTILS_H
19 
20 #include <utils/Errors.h>
21 #include <selinux/selinux.h>
22 
23 #include <vector>
24 #include <string>
25 
26 // DISALLOW_COPY_AND_ASSIGN disallows the copy and operator= functions. It goes in the private:
27 // declarations in a class.
28 #if !defined(DISALLOW_COPY_AND_ASSIGN)
29 #define DISALLOW_COPY_AND_ASSIGN(TypeName) \
30     TypeName(const TypeName&) = delete;  \
31     void operator=(const TypeName&) = delete
32 #endif
33 
34 namespace android {
35 namespace vold {
36 
37 /* SELinux contexts used depending on the block device type */
38 extern security_context_t sBlkidContext;
39 extern security_context_t sBlkidUntrustedContext;
40 extern security_context_t sFsckContext;
41 extern security_context_t sFsckUntrustedContext;
42 
43 status_t CreateDeviceNode(const std::string& path, dev_t dev);
44 status_t DestroyDeviceNode(const std::string& path);
45 
46 /* fs_prepare_dir wrapper that creates with SELinux context */
47 status_t PrepareDir(const std::string& path, mode_t mode, uid_t uid, gid_t gid);
48 
49 /* Really unmounts the path, killing active processes along the way */
50 status_t ForceUnmount(const std::string& path);
51 
52 /* Creates bind mount from source to target */
53 status_t BindMount(const std::string& source, const std::string& target);
54 
55 /* Reads filesystem metadata from device at path */
56 status_t ReadMetadata(const std::string& path, std::string& fsType,
57         std::string& fsUuid, std::string& fsLabel);
58 
59 /* Reads filesystem metadata from untrusted device at path */
60 status_t ReadMetadataUntrusted(const std::string& path, std::string& fsType,
61         std::string& fsUuid, std::string& fsLabel);
62 
63 /* Returns either WEXITSTATUS() status, or a negative errno */
64 status_t ForkExecvp(const std::vector<std::string>& args);
65 status_t ForkExecvp(const std::vector<std::string>& args, security_context_t context);
66 
67 status_t ForkExecvp(const std::vector<std::string>& args,
68         std::vector<std::string>& output);
69 status_t ForkExecvp(const std::vector<std::string>& args,
70         std::vector<std::string>& output, security_context_t context);
71 
72 pid_t ForkExecvpAsync(const std::vector<std::string>& args);
73 
74 status_t ReadRandomBytes(size_t bytes, std::string& out);
75 
76 /* Converts hex string to raw bytes, ignoring [ :-] */
77 status_t HexToStr(const std::string& hex, std::string& str);
78 /* Converts raw bytes to hex string */
79 status_t StrToHex(const std::string& str, std::string& hex);
80 /* Normalize given hex string into consistent format */
81 status_t NormalizeHex(const std::string& in, std::string& out);
82 
83 uint64_t GetFreeBytes(const std::string& path);
84 uint64_t GetTreeBytes(const std::string& path);
85 
86 bool IsFilesystemSupported(const std::string& fsType);
87 
88 /* Wipes contents of block device at given path */
89 status_t WipeBlockDevice(const std::string& path);
90 
91 std::string BuildKeyPath(const std::string& partGuid);
92 
93 dev_t GetDevice(const std::string& path);
94 
95 std::string DefaultFstabPath();
96 
97 }  // namespace vold
98 }  // namespace android
99 
100 #endif
101