aosp12/system/vold/VolumeManager.h

243 lines
8.6 KiB
C++

/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef ANDROID_VOLD_VOLUME_MANAGER_H
#define ANDROID_VOLD_VOLUME_MANAGER_H
#include <fnmatch.h>
#include <pthread.h>
#include <stdlib.h>
#include <list>
#include <mutex>
#include <set>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <android-base/unique_fd.h>
#include <cutils/multiuser.h>
#include <sysutils/NetlinkEvent.h>
#include <utils/List.h>
#include <utils/Timers.h>
#include "android/os/IVoldListener.h"
#include "model/Disk.h"
#include "model/VolumeBase.h"
class VolumeManager {
private:
static VolumeManager* sInstance;
bool mDebug;
public:
virtual ~VolumeManager();
// TODO: pipe all requests through VM to avoid exposing this lock
std::mutex& getLock() { return mLock; }
std::mutex& getCryptLock() { return mCryptLock; }
void setListener(android::sp<android::os::IVoldListener> listener) { mListener = listener; }
android::sp<android::os::IVoldListener> getListener() const { return mListener; }
int start();
void handleBlockEvent(NetlinkEvent* evt);
class DiskSource {
public:
DiskSource(const std::string& sysPattern, const std::string& nickname, int flags)
: mSysPattern(sysPattern), mNickname(nickname), mFlags(flags) {}
bool matches(const std::string& sysPath) {
return !fnmatch(mSysPattern.c_str(), sysPath.c_str(), 0);
}
const std::string& getNickname() const { return mNickname; }
int getFlags() const { return mFlags; }
private:
std::string mSysPattern;
std::string mNickname;
int mFlags;
};
void addDiskSource(const std::shared_ptr<DiskSource>& diskSource);
std::shared_ptr<android::vold::Disk> findDisk(const std::string& id);
std::shared_ptr<android::vold::VolumeBase> findVolume(const std::string& id);
template <typename Fn>
std::shared_ptr<android::vold::VolumeBase> findVolumeWithFilter(Fn fn) {
for (const auto& vol : mInternalEmulatedVolumes) {
if (fn(*vol)) {
return vol;
}
}
for (const auto& disk : mDisks) {
for (const auto& vol : disk->getVolumes()) {
if (fn(*vol)) {
return vol;
}
}
}
return nullptr;
}
void listVolumes(android::vold::VolumeBase::Type type, std::list<std::string>& list) const;
const std::set<userid_t>& getStartedUsers() const { return mStartedUsers; }
int forgetPartition(const std::string& partGuid, const std::string& fsUuid);
int onUserAdded(userid_t userId, int userSerialNumber);
int onUserRemoved(userid_t userId);
int onUserStarted(userid_t userId);
int onUserStopped(userid_t userId);
void createPendingDisksIfNeeded();
int onSecureKeyguardStateChanged(bool isShowing);
int remountUid(uid_t uid, int32_t remountMode) { return 0; }
int handleAppStorageDirs(int uid, int pid,
bool doUnmount, const std::vector<std::string>& packageNames);
/* Aborts all FUSE filesystems, in case the FUSE daemon is no longer up. */
int abortFuse();
/* Reset all internal state, typically during framework boot */
int reset();
/* Prepare for device shutdown, safely unmounting all devices */
int shutdown();
/* Unmount all volumes, usually for encryption */
int unmountAll();
int updateVirtualDisk();
int setDebug(bool enable);
bool forkAndRemountStorage(int uid, int pid, bool doUnmount,
const std::vector<std::string>& packageNames);
static VolumeManager* Instance();
/*
* Creates a directory 'path' for an application, automatically creating
* directories along the given path if they don't exist yet.
*
* Example:
* path = /storage/emulated/0/Android/data/com.foo/files/
*
* This function will first match the first part of the path with the volume
* root of any known volumes; in this case, "/storage/emulated/0" matches
* with the volume root of the emulated volume for user 0.
*
* The subseqent part of the path must start with one of the well-known
* Android/ data directories, /Android/data, /Android/obb or
* /Android/media.
*
* The final part of the path is application specific. This function will
* create all directories, including the application-specific ones, and
* set the UID of all app-specific directories below the well-known data
* directories to the 'appUid' argument. In the given example, the UID
* of /storage/emulated/0/Android/data/com.foo and
* /storage/emulated/0/Android/data/com.foo/files would be set to 'appUid'.
*
* The UID/GID of the parent directories will be set according to the
* requirements of the underlying filesystem and are of no concern to the
* caller.
*
* If fixupExistingOnly is set, we make sure to fixup any existing dirs and
* files in the passed in path, but only if that path exists; if it doesn't
* exist, this function doesn't create them.
*
* If skipIfDirExists is set, we will not fix any existing dirs, we will
* only create app dirs if it doesn't exist.
*
* Validates that given paths are absolute and that they contain no relative
* "." or ".." paths or symlinks. Last path segment is treated as filename
* and ignored, unless the path ends with "/". Also ensures that path
* belongs to a volume managed by vold.
*/
int setupAppDir(const std::string& path, int32_t appUid, bool fixupExistingOnly = false,
bool skipIfDirExists = false);
/**
* Fixes up an existing application directory, as if it was created with
* setupAppDir() above. This includes fixing up the UID/GID, permissions and
* project IDs of the contained files and directories.
*/
int fixupAppDir(const std::string& path, int32_t appUid);
// Called before zygote starts to ensure dir exists so zygote can bind mount them.
int ensureAppDirsCreated(const std::vector<std::string>& paths, int32_t appUid);
int createObb(const std::string& path, const std::string& key, int32_t ownerGid,
std::string* outVolId);
int destroyObb(const std::string& volId);
int createStubVolume(const std::string& sourcePath, const std::string& mountPath,
const std::string& fsType, const std::string& fsUuid,
const std::string& fsLabel, int32_t flags, std::string* outVolId);
int destroyStubVolume(const std::string& volId);
int mountAppFuse(uid_t uid, int mountId, android::base::unique_fd* device_fd);
int unmountAppFuse(uid_t uid, int mountId);
int openAppFuseFile(uid_t uid, int mountId, int fileId, int flags);
private:
VolumeManager();
void readInitialState();
int linkPrimary(userid_t userId);
void createEmulatedVolumesForUser(userid_t userId);
void destroyEmulatedVolumesForUser(userid_t userId);
void handleDiskAdded(const std::shared_ptr<android::vold::Disk>& disk);
void handleDiskChanged(dev_t device);
void handleDiskRemoved(dev_t device);
bool updateFuseMountedProperty();
std::mutex mLock;
std::mutex mCryptLock;
android::sp<android::os::IVoldListener> mListener;
std::list<std::shared_ptr<DiskSource>> mDiskSources;
std::list<std::shared_ptr<android::vold::Disk>> mDisks;
std::list<std::shared_ptr<android::vold::Disk>> mPendingDisks;
std::list<std::shared_ptr<android::vold::VolumeBase>> mObbVolumes;
std::list<std::shared_ptr<android::vold::VolumeBase>> mInternalEmulatedVolumes;
std::unordered_map<userid_t, int> mAddedUsers;
// This needs to be a regular set because we care about the ordering here;
// user 0 should always go first, because it is responsible for sdcardfs.
std::set<userid_t> mStartedUsers;
std::string mVirtualDiskPath;
std::shared_ptr<android::vold::Disk> mVirtualDisk;
std::shared_ptr<android::vold::VolumeBase> mPrimary;
int mNextObbId;
int mNextStubId;
bool mSecureKeyguardShowing;
};
#endif