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 <cutils/multiuser.h> 22 #include <selinux/selinux.h> 23 24 #include <vector> 25 #include <string> 26 27 // DISALLOW_COPY_AND_ASSIGN disallows the copy and operator= functions. It goes in the private: 28 // declarations in a class. 29 #if !defined(DISALLOW_COPY_AND_ASSIGN) 30 #define DISALLOW_COPY_AND_ASSIGN(TypeName) \ 31 TypeName(const TypeName&) = delete; \ 32 void operator=(const TypeName&) = delete 33 #endif 34 35 struct DIR; 36 37 namespace android { 38 namespace vold { 39 40 /* SELinux contexts used depending on the block device type */ 41 extern security_context_t sBlkidContext; 42 extern security_context_t sBlkidUntrustedContext; 43 extern security_context_t sFsckContext; 44 extern security_context_t sFsckUntrustedContext; 45 46 status_t CreateDeviceNode(const std::string& path, dev_t dev); 47 status_t DestroyDeviceNode(const std::string& path); 48 49 /* fs_prepare_dir wrapper that creates with SELinux context */ 50 status_t PrepareDir(const std::string& path, mode_t mode, uid_t uid, gid_t gid); 51 52 /* Really unmounts the path, killing active processes along the way */ 53 status_t ForceUnmount(const std::string& path); 54 55 /* Kills any processes using given path */ 56 status_t KillProcessesUsingPath(const std::string& path); 57 58 /* Creates bind mount from source to target */ 59 status_t BindMount(const std::string& source, const std::string& target); 60 61 /* Reads filesystem metadata from device at path */ 62 status_t ReadMetadata(const std::string& path, std::string& fsType, 63 std::string& fsUuid, std::string& fsLabel); 64 65 /* Reads filesystem metadata from untrusted device at path */ 66 status_t ReadMetadataUntrusted(const std::string& path, std::string& fsType, 67 std::string& fsUuid, std::string& fsLabel); 68 69 /* Returns either WEXITSTATUS() status, or a negative errno */ 70 status_t ForkExecvp(const std::vector<std::string>& args); 71 status_t ForkExecvp(const std::vector<std::string>& args, security_context_t context); 72 73 status_t ForkExecvp(const std::vector<std::string>& args, 74 std::vector<std::string>& output); 75 status_t ForkExecvp(const std::vector<std::string>& args, 76 std::vector<std::string>& output, security_context_t context); 77 78 pid_t ForkExecvpAsync(const std::vector<std::string>& args); 79 80 status_t ReadRandomBytes(size_t bytes, std::string& out); 81 82 /* Converts hex string to raw bytes, ignoring [ :-] */ 83 status_t HexToStr(const std::string& hex, std::string& str); 84 /* Converts raw bytes to hex string */ 85 status_t StrToHex(const std::string& str, std::string& hex); 86 /* Normalize given hex string into consistent format */ 87 status_t NormalizeHex(const std::string& in, std::string& out); 88 89 uint64_t GetFreeBytes(const std::string& path); 90 uint64_t GetTreeBytes(const std::string& path); 91 92 bool IsFilesystemSupported(const std::string& fsType); 93 94 /* Wipes contents of block device at given path */ 95 status_t WipeBlockDevice(const std::string& path); 96 97 std::string BuildKeyPath(const std::string& partGuid); 98 99 std::string BuildDataSystemLegacyPath(userid_t userid); 100 std::string BuildDataSystemCePath(userid_t userid); 101 std::string BuildDataSystemDePath(userid_t userid); 102 std::string BuildDataMiscLegacyPath(userid_t userid); 103 std::string BuildDataMiscCePath(userid_t userid); 104 std::string BuildDataMiscDePath(userid_t userid); 105 std::string BuildDataProfilesDePath(userid_t userid); 106 std::string BuildDataProfilesForeignDexDePath(userid_t userid); 107 108 std::string BuildDataPath(const char* volumeUuid); 109 std::string BuildDataMediaCePath(const char* volumeUuid, userid_t userid); 110 std::string BuildDataUserCePath(const char* volumeUuid, userid_t userid); 111 std::string BuildDataUserDePath(const char* volumeUuid, userid_t userid); 112 113 dev_t GetDevice(const std::string& path); 114 115 std::string DefaultFstabPath(); 116 117 status_t SaneReadLinkAt(int dirfd, const char* path, char* buf, size_t bufsiz); 118 119 class ScopedFd { 120 const int fd_; 121 public: 122 ScopedFd(int fd); 123 ~ScopedFd(); get()124 int get() const { return fd_; } 125 126 DISALLOW_COPY_AND_ASSIGN(ScopedFd); 127 }; 128 129 class ScopedDir { 130 DIR* const dir_; 131 public: 132 ScopedDir(DIR* dir); 133 ~ScopedDir(); get()134 DIR* get() const { return dir_; } 135 136 DISALLOW_COPY_AND_ASSIGN(ScopedDir); 137 }; 138 139 /* Checks if Android is running in QEMU */ 140 bool IsRunningInEmulator(); 141 142 } // namespace vold 143 } // namespace android 144 145 #endif 146