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 "KeyBuffer.h" 21 22 #include <android-base/macros.h> 23 #include <cutils/multiuser.h> 24 #include <selinux/selinux.h> 25 #include <utils/Errors.h> 26 27 #include <chrono> 28 #include <string> 29 #include <vector> 30 31 struct DIR; 32 33 namespace android { 34 namespace vold { 35 36 /* SELinux contexts used depending on the block device type */ 37 extern security_context_t sBlkidContext; 38 extern security_context_t sBlkidUntrustedContext; 39 extern security_context_t sFsckContext; 40 extern security_context_t sFsckUntrustedContext; 41 42 // TODO remove this with better solution, b/64143519 43 extern bool sSleepOnUnmount; 44 45 status_t CreateDeviceNode(const std::string& path, dev_t dev); 46 status_t DestroyDeviceNode(const std::string& path); 47 48 /* fs_prepare_dir wrapper that creates with SELinux context */ 49 status_t PrepareDir(const std::string& path, mode_t mode, uid_t uid, gid_t gid); 50 51 /* Really unmounts the path, killing active processes along the way */ 52 status_t ForceUnmount(const std::string& path); 53 54 /* Kills any processes using given path */ 55 status_t KillProcessesUsingPath(const std::string& path); 56 57 /* Creates bind mount from source to target */ 58 status_t BindMount(const std::string& source, const std::string& target); 59 60 /** Creates a symbolic link to target */ 61 status_t Symlink(const std::string& target, const std::string& linkpath); 62 63 /** Calls unlink(2) at linkpath */ 64 status_t Unlink(const std::string& linkpath); 65 66 /** Creates the given directory if it is not already available */ 67 status_t CreateDir(const std::string& dir, mode_t mode); 68 69 bool FindValue(const std::string& raw, const std::string& key, std::string* value); 70 71 /* Reads filesystem metadata from device at path */ 72 status_t ReadMetadata(const std::string& path, std::string* fsType, std::string* fsUuid, 73 std::string* fsLabel); 74 75 /* Reads filesystem metadata from untrusted device at path */ 76 status_t ReadMetadataUntrusted(const std::string& path, std::string* fsType, std::string* fsUuid, 77 std::string* fsLabel); 78 79 /* Returns either WEXITSTATUS() status, or a negative errno */ 80 status_t ForkExecvp(const std::vector<std::string>& args, std::vector<std::string>* output = nullptr, 81 security_context_t context = nullptr); 82 83 pid_t ForkExecvpAsync(const std::vector<std::string>& args); 84 85 /* Gets block device size in bytes */ 86 status_t GetBlockDevSize(int fd, uint64_t* size); 87 status_t GetBlockDevSize(const std::string& path, uint64_t* size); 88 /* Gets block device size in 512 byte sectors */ 89 status_t GetBlockDev512Sectors(const std::string& path, uint64_t* nr_sec); 90 91 status_t ReadRandomBytes(size_t bytes, std::string& out); 92 status_t ReadRandomBytes(size_t bytes, char* buffer); 93 status_t GenerateRandomUuid(std::string& out); 94 95 /* Converts hex string to raw bytes, ignoring [ :-] */ 96 status_t HexToStr(const std::string& hex, std::string& str); 97 /* Converts raw bytes to hex string */ 98 status_t StrToHex(const std::string& str, std::string& hex); 99 /* Converts raw key bytes to hex string */ 100 status_t StrToHex(const KeyBuffer& str, KeyBuffer& hex); 101 /* Normalize given hex string into consistent format */ 102 status_t NormalizeHex(const std::string& in, std::string& out); 103 104 uint64_t GetFreeBytes(const std::string& path); 105 uint64_t GetTreeBytes(const std::string& path); 106 107 bool IsFilesystemSupported(const std::string& fsType); 108 109 /* Wipes contents of block device at given path */ 110 status_t WipeBlockDevice(const std::string& path); 111 112 std::string BuildKeyPath(const std::string& partGuid); 113 114 std::string BuildDataSystemLegacyPath(userid_t userid); 115 std::string BuildDataSystemCePath(userid_t userid); 116 std::string BuildDataSystemDePath(userid_t userid); 117 std::string BuildDataMiscLegacyPath(userid_t userid); 118 std::string BuildDataMiscCePath(userid_t userid); 119 std::string BuildDataMiscDePath(userid_t userid); 120 std::string BuildDataProfilesDePath(userid_t userid); 121 std::string BuildDataVendorCePath(userid_t userid); 122 std::string BuildDataVendorDePath(userid_t userid); 123 124 std::string BuildDataPath(const std::string& volumeUuid); 125 std::string BuildDataMediaCePath(const std::string& volumeUuid, userid_t userid); 126 std::string BuildDataUserCePath(const std::string& volumeUuid, userid_t userid); 127 std::string BuildDataUserDePath(const std::string& volumeUuid, userid_t userid); 128 129 dev_t GetDevice(const std::string& path); 130 131 status_t RestoreconRecursive(const std::string& path); 132 133 // TODO: promote to android::base 134 bool Readlinkat(int dirfd, const std::string& path, std::string* result); 135 136 /* Checks if Android is running in QEMU */ 137 bool IsRunningInEmulator(); 138 139 status_t UnmountTreeWithPrefix(const std::string& prefix); 140 status_t UnmountTree(const std::string& mountPoint); 141 142 status_t DeleteDirContentsAndDir(const std::string& pathname); 143 status_t DeleteDirContents(const std::string& pathname); 144 145 status_t WaitForFile(const char* filename, std::chrono::nanoseconds timeout); 146 147 bool FsyncDirectory(const std::string& dirname); 148 149 bool writeStringToFile(const std::string& payload, const std::string& filename); 150 } // namespace vold 151 } // namespace android 152 153 #endif 154