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 <string>
27 #include <unordered_map>
28 #include <unordered_set>
29 
30 #include <android-base/unique_fd.h>
31 #include <cutils/multiuser.h>
32 #include <sysutils/NetlinkEvent.h>
33 #include <utils/List.h>
34 #include <utils/Timers.h>
35 
36 #include "android/os/IVoldListener.h"
37 
38 #include "model/Disk.h"
39 #include "model/VolumeBase.h"
40 
41 class VolumeManager {
42   private:
43     static VolumeManager* sInstance;
44 
45     bool mDebug;
46 
47   public:
48     virtual ~VolumeManager();
49 
50     // TODO: pipe all requests through VM to avoid exposing this lock
getLock()51     std::mutex& getLock() { return mLock; }
getCryptLock()52     std::mutex& getCryptLock() { return mCryptLock; }
53 
setListener(android::sp<android::os::IVoldListener> listener)54     void setListener(android::sp<android::os::IVoldListener> listener) { mListener = listener; }
getListener()55     android::sp<android::os::IVoldListener> getListener() const { return mListener; }
56 
57     int start();
58     int stop();
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     void listVolumes(android::vold::VolumeBase::Type type, std::list<std::string>& list) const;
86 
87     int forgetPartition(const std::string& partGuid, const std::string& fsUuid);
88 
89     int onUserAdded(userid_t userId, int userSerialNumber);
90     int onUserRemoved(userid_t userId);
91     int onUserStarted(userid_t userId);
92     int onUserStopped(userid_t userId);
93 
94     int onSecureKeyguardStateChanged(bool isShowing);
95 
96     int setPrimary(const std::shared_ptr<android::vold::VolumeBase>& vol);
97 
98     int remountUid(uid_t uid, int32_t remountMode);
99 
100     /* Reset all internal state, typically during framework boot */
101     int reset();
102     /* Prepare for device shutdown, safely unmounting all devices */
103     int shutdown();
104     /* Unmount all volumes, usually for encryption */
105     int unmountAll();
106 
107     int updateVirtualDisk();
108     int setDebug(bool enable);
109 
110     static VolumeManager* Instance();
111 
112     /*
113      * Ensure that all directories along given path exist, creating parent
114      * directories as needed.  Validates that given path is absolute and that
115      * it contains no relative "." or ".." paths or symlinks.  Last path segment
116      * is treated as filename and ignored, unless the path ends with "/".  Also
117      * ensures that path belongs to a volume managed by vold.
118      */
119     int mkdirs(const std::string& path);
120 
121     int createObb(const std::string& path, const std::string& key, int32_t ownerGid,
122                   std::string* outVolId);
123     int destroyObb(const std::string& volId);
124 
125     int createStubVolume(const std::string& sourcePath, const std::string& mountPath,
126                          const std::string& fsType, const std::string& fsUuid,
127                          const std::string& fsLabel, std::string* outVolId);
128     int destroyStubVolume(const std::string& volId);
129 
130     int mountAppFuse(uid_t uid, int mountId, android::base::unique_fd* device_fd);
131     int unmountAppFuse(uid_t uid, int mountId);
132     int openAppFuseFile(uid_t uid, int mountId, int fileId, int flags);
133 
134   private:
135     VolumeManager();
136     void readInitialState();
137 
138     int linkPrimary(userid_t userId);
139 
140     void handleDiskAdded(const std::shared_ptr<android::vold::Disk>& disk);
141     void handleDiskChanged(dev_t device);
142     void handleDiskRemoved(dev_t device);
143 
144     std::mutex mLock;
145     std::mutex mCryptLock;
146 
147     android::sp<android::os::IVoldListener> mListener;
148 
149     std::list<std::shared_ptr<DiskSource>> mDiskSources;
150     std::list<std::shared_ptr<android::vold::Disk>> mDisks;
151     std::list<std::shared_ptr<android::vold::Disk>> mPendingDisks;
152     std::list<std::shared_ptr<android::vold::VolumeBase>> mObbVolumes;
153     std::list<std::shared_ptr<android::vold::VolumeBase>> mStubVolumes;
154 
155     std::unordered_map<userid_t, int> mAddedUsers;
156     std::unordered_set<userid_t> mStartedUsers;
157 
158     std::string mVirtualDiskPath;
159     std::shared_ptr<android::vold::Disk> mVirtualDisk;
160     std::shared_ptr<android::vold::VolumeBase> mInternalEmulated;
161     std::shared_ptr<android::vold::VolumeBase> mPrimary;
162 
163     int mNextObbId;
164     int mNextStubVolumeId;
165     bool mSecureKeyguardShowing;
166 };
167 
168 #endif
169