1 /* 2 * Copyright (C) 2008 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_VOLUME_MANAGER_H 18 #define ANDROID_VOLD_VOLUME_MANAGER_H 19 20 #include <fnmatch.h> 21 #include <pthread.h> 22 #include <stdlib.h> 23 24 #include <list> 25 #include <mutex> 26 #include <set> 27 #include <string> 28 #include <unordered_map> 29 #include <unordered_set> 30 31 #include <android-base/unique_fd.h> 32 #include <cutils/multiuser.h> 33 #include <sysutils/NetlinkEvent.h> 34 #include <utils/List.h> 35 #include <utils/Timers.h> 36 37 #include "android/os/IVoldListener.h" 38 39 #include "model/Disk.h" 40 #include "model/VolumeBase.h" 41 42 class VolumeManager { 43 private: 44 static VolumeManager* sInstance; 45 46 bool mDebug; 47 48 public: 49 virtual ~VolumeManager(); 50 51 // TODO: pipe all requests through VM to avoid exposing this lock getLock()52 std::mutex& getLock() { return mLock; } getCryptLock()53 std::mutex& getCryptLock() { return mCryptLock; } 54 setListener(android::sp<android::os::IVoldListener> listener)55 void setListener(android::sp<android::os::IVoldListener> listener) { mListener = listener; } getListener()56 android::sp<android::os::IVoldListener> getListener() const { return mListener; } 57 58 int start(); 59 60 void handleBlockEvent(NetlinkEvent* evt); 61 62 class DiskSource { 63 public: DiskSource(const std::string & sysPattern,const std::string & nickname,int flags)64 DiskSource(const std::string& sysPattern, const std::string& nickname, int flags) 65 : mSysPattern(sysPattern), mNickname(nickname), mFlags(flags) {} 66 matches(const std::string & sysPath)67 bool matches(const std::string& sysPath) { 68 return !fnmatch(mSysPattern.c_str(), sysPath.c_str(), 0); 69 } 70 getNickname()71 const std::string& getNickname() const { return mNickname; } getFlags()72 int getFlags() const { return mFlags; } 73 74 private: 75 std::string mSysPattern; 76 std::string mNickname; 77 int mFlags; 78 }; 79 80 void addDiskSource(const std::shared_ptr<DiskSource>& diskSource); 81 82 std::shared_ptr<android::vold::Disk> findDisk(const std::string& id); 83 std::shared_ptr<android::vold::VolumeBase> findVolume(const std::string& id); 84 85 template <typename Fn> findVolumeWithFilter(Fn fn)86 std::shared_ptr<android::vold::VolumeBase> findVolumeWithFilter(Fn fn) { 87 for (const auto& vol : mInternalEmulatedVolumes) { 88 if (fn(*vol)) { 89 return vol; 90 } 91 } 92 for (const auto& disk : mDisks) { 93 for (const auto& vol : disk->getVolumes()) { 94 if (fn(*vol)) { 95 return vol; 96 } 97 } 98 } 99 100 return nullptr; 101 } 102 103 void listVolumes(android::vold::VolumeBase::Type type, std::list<std::string>& list) const; 104 getStartedUsers()105 const std::set<userid_t>& getStartedUsers() const { return mStartedUsers; } 106 107 int forgetPartition(const std::string& partGuid, const std::string& fsUuid); 108 109 int onUserAdded(userid_t userId, int userSerialNumber); 110 int onUserRemoved(userid_t userId); 111 int onUserStarted(userid_t userId); 112 int onUserStopped(userid_t userId); 113 114 void createPendingDisksIfNeeded(); 115 int onSecureKeyguardStateChanged(bool isShowing); 116 remountUid(uid_t uid,int32_t remountMode)117 int remountUid(uid_t uid, int32_t remountMode) { return 0; } 118 int handleAppStorageDirs(int uid, int pid, 119 bool doUnmount, const std::vector<std::string>& packageNames); 120 121 /* Aborts all FUSE filesystems, in case the FUSE daemon is no longer up. */ 122 int abortFuse(); 123 /* Reset all internal state, typically during framework boot */ 124 int reset(); 125 /* Prepare for device shutdown, safely unmounting all devices */ 126 int shutdown(); 127 /* Unmount all volumes, usually for encryption */ 128 int unmountAll(); 129 130 int updateVirtualDisk(); 131 int setDebug(bool enable); 132 133 bool forkAndRemountStorage(int uid, int pid, bool doUnmount, 134 const std::vector<std::string>& packageNames); 135 136 static VolumeManager* Instance(); 137 138 /* 139 * Creates a directory 'path' for an application, automatically creating 140 * directories along the given path if they don't exist yet. 141 * 142 * Example: 143 * path = /storage/emulated/0/Android/data/com.foo/files/ 144 * 145 * This function will first match the first part of the path with the volume 146 * root of any known volumes; in this case, "/storage/emulated/0" matches 147 * with the volume root of the emulated volume for user 0. 148 * 149 * The subseqent part of the path must start with one of the well-known 150 * Android/ data directories, /Android/data, /Android/obb or 151 * /Android/media. 152 * 153 * The final part of the path is application specific. This function will 154 * create all directories, including the application-specific ones, and 155 * set the UID of all app-specific directories below the well-known data 156 * directories to the 'appUid' argument. In the given example, the UID 157 * of /storage/emulated/0/Android/data/com.foo and 158 * /storage/emulated/0/Android/data/com.foo/files would be set to 'appUid'. 159 * 160 * The UID/GID of the parent directories will be set according to the 161 * requirements of the underlying filesystem and are of no concern to the 162 * caller. 163 * 164 * If fixupExistingOnly is set, we make sure to fixup any existing dirs and 165 * files in the passed in path, but only if that path exists; if it doesn't 166 * exist, this function doesn't create them. 167 * 168 * If skipIfDirExists is set, we will not fix any existing dirs, we will 169 * only create app dirs if it doesn't exist. 170 * 171 * Validates that given paths are absolute and that they contain no relative 172 * "." or ".." paths or symlinks. Last path segment is treated as filename 173 * and ignored, unless the path ends with "/". Also ensures that path 174 * belongs to a volume managed by vold. 175 */ 176 int setupAppDir(const std::string& path, int32_t appUid, bool fixupExistingOnly = false, 177 bool skipIfDirExists = false); 178 179 /** 180 * Fixes up an existing application directory, as if it was created with 181 * setupAppDir() above. This includes fixing up the UID/GID, permissions and 182 * project IDs of the contained files and directories. 183 */ 184 int fixupAppDir(const std::string& path, int32_t appUid); 185 186 // Called before zygote starts to ensure dir exists so zygote can bind mount them. 187 int ensureAppDirsCreated(const std::vector<std::string>& paths, int32_t appUid); 188 189 int createObb(const std::string& path, const std::string& key, int32_t ownerGid, 190 std::string* outVolId); 191 int destroyObb(const std::string& volId); 192 193 int createStubVolume(const std::string& sourcePath, const std::string& mountPath, 194 const std::string& fsType, const std::string& fsUuid, 195 const std::string& fsLabel, int32_t flags, std::string* outVolId); 196 int destroyStubVolume(const std::string& volId); 197 198 int mountAppFuse(uid_t uid, int mountId, android::base::unique_fd* device_fd); 199 int unmountAppFuse(uid_t uid, int mountId); 200 int openAppFuseFile(uid_t uid, int mountId, int fileId, int flags); 201 202 private: 203 VolumeManager(); 204 void readInitialState(); 205 206 int linkPrimary(userid_t userId); 207 208 void createEmulatedVolumesForUser(userid_t userId); 209 void destroyEmulatedVolumesForUser(userid_t userId); 210 211 void handleDiskAdded(const std::shared_ptr<android::vold::Disk>& disk); 212 void handleDiskChanged(dev_t device); 213 void handleDiskRemoved(dev_t device); 214 215 bool updateFuseMountedProperty(); 216 217 std::mutex mLock; 218 std::mutex mCryptLock; 219 220 android::sp<android::os::IVoldListener> mListener; 221 222 std::list<std::shared_ptr<DiskSource>> mDiskSources; 223 std::list<std::shared_ptr<android::vold::Disk>> mDisks; 224 std::list<std::shared_ptr<android::vold::Disk>> mPendingDisks; 225 std::list<std::shared_ptr<android::vold::VolumeBase>> mObbVolumes; 226 std::list<std::shared_ptr<android::vold::VolumeBase>> mInternalEmulatedVolumes; 227 228 std::unordered_map<userid_t, int> mAddedUsers; 229 // This needs to be a regular set because we care about the ordering here; 230 // user 0 should always go first, because it is responsible for sdcardfs. 231 std::set<userid_t> mStartedUsers; 232 233 std::string mVirtualDiskPath; 234 std::shared_ptr<android::vold::Disk> mVirtualDisk; 235 std::shared_ptr<android::vold::VolumeBase> mPrimary; 236 237 int mNextObbId; 238 int mNextStubId; 239 bool mSecureKeyguardShowing; 240 }; 241 242 #endif 243