VolumeManager.h - SHIFTPHONES/android_system_vold - Gitiles

 /*
  * 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/DiskPartition.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 partnum, int flags,
                 const std::string& fstype, const std::string mntopts)
                 : mSysPattern(sysPattern), mNickname(nickname),
                 mPartNum(partnum), mFlags(flags),
                 mFsType(fstype), mMntOpts(mntopts) {}

         bool matches(const std::string& sysPath) {
             return !fnmatch(mSysPattern.c_str(), sysPath.c_str(), 0);
         }

         const std::string& getNickname() const { return mNickname; }
         int getPartNum() const { return mPartNum; }
         int getFlags() const { return mFlags; }
         const std::string& getFsType() { return mFsType; }
         const std::string& getMntOpts() { return mMntOpts; }

       private:
         std::string mSysPattern;
         std::string mNickname;
         int mPartNum;
         int mFlags;
         std::string mFsType;
         std::string mMntOpts;
     };

     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, 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
	/*
	* 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/DiskPartition.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 partnum, int flags,
	const std::string& fstype, const std::string mntopts)
	: mSysPattern(sysPattern), mNickname(nickname),
	mPartNum(partnum), mFlags(flags),
	mFsType(fstype), mMntOpts(mntopts) {}

	bool matches(const std::string& sysPath) {
	return !fnmatch(mSysPattern.c_str(), sysPath.c_str(), 0);
	}

	const std::string& getNickname() const { return mNickname; }
	int getPartNum() const { return mPartNum; }
	int getFlags() const { return mFlags; }
	const std::string& getFsType() { return mFsType; }
	const std::string& getMntOpts() { return mMntOpts; }

	private:
	std::string mSysPattern;
	std::string mNickname;
	int mPartNum;
	int mFlags;
	std::string mFsType;
	std::string mMntOpts;
	};

	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, 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