MIDI: Add virtual devices per user

Create virtual MIDI devices per user.

Before, only the system user could create virtual MIDI devices.
These devices could be accessed by all users.
No other user could create virtual devices.

With this change, all users can create can install an app that provides
a Virtual MIDI Device Service.
getDevices() surfaces devices that can be opened by that user.
openDevice() rejects devices that are not created by that user.

Users can no longer open virtual MIDI devices created by other users.

Bug: 279553006
Bug: 272175328
Bug: 28673954
Test: atest CtsMidiTestCases
Test: Midi Synth Ex app  with Midi Keyboard app
Test: Installing virtual midi apps on multiple users
Change-Id: I7a2cf9a788cf1ccb701ef6be63295f336a479fe4

1 files changed, 132 insertions, 54 deletions

diff --git a/services/midi/java/com/android/server/midi/MidiService.java b/services/midi/java/com/android/server/midi/MidiService.java
index 4aba30a661ad..f660b42457db 100644
--- a/services/midi/java/com/android/server/midi/MidiService.java
+++ b/services/midi/java/com/android/server/midi/MidiService.java
@@ -16,7 +16,9 @@
 
 package com.android.server.midi;
 
+import android.Manifest;
 import android.annotation.NonNull;
+import android.annotation.RequiresPermission;
 import android.bluetooth.BluetoothDevice;
 import android.bluetooth.BluetoothUuid;
 import android.content.BroadcastReceiver;
@@ -48,6 +50,7 @@ import android.os.ParcelUuid;
 import android.os.Process;
 import android.os.RemoteException;
 import android.os.UserHandle;
+import android.os.UserManager;
 import android.util.EventLog;
 import android.util.Log;
 
@@ -81,6 +84,11 @@ import java.util.concurrent.atomic.AtomicLong;
 //   2. synchronized (mDeviceConnections)
 //TODO Introduce a single lock object to lock the whole state and avoid the requirement above.
 
+// All users should be able to connect to USB and Bluetooth MIDI devices.
+// All users can create can install an app that provides, a Virtual MIDI Device Service.
+// Users can not open virtual MIDI devices created by other users.
+// getDevices() surfaces devices that can be opened by that user.
+// openDevice() rejects devices that are cannot be opened by that user.
 public class MidiService extends IMidiManager.Stub {
 
     public static class Lifecycle extends SystemService {
@@ -97,10 +105,21 @@ public class MidiService extends IMidiManager.Stub {
         }
 
         @Override
+        @RequiresPermission(allOf = {Manifest.permission.INTERACT_ACROSS_USERS},
+                anyOf = {Manifest.permission.QUERY_USERS,
+                Manifest.permission.CREATE_USERS,
+                Manifest.permission.MANAGE_USERS})
+        public void onUserStarting(@NonNull TargetUser user) {
+            mMidiService.onStartOrUnlockUser(user, false /* matchDirectBootUnaware */);
+        }
+
+        @Override
+        @RequiresPermission(allOf = {Manifest.permission.INTERACT_ACROSS_USERS},
+                anyOf = {Manifest.permission.QUERY_USERS,
+                Manifest.permission.CREATE_USERS,
+                Manifest.permission.MANAGE_USERS})
         public void onUserUnlocking(@NonNull TargetUser user) {
-            if (user.getUserIdentifier()  == UserHandle.USER_SYSTEM) {
-                mMidiService.onUnlockUser();
-            }
+            mMidiService.onStartOrUnlockUser(user, true /* matchDirectBootUnaware */);
         }
     }
 
@@ -134,6 +153,7 @@ public class MidiService extends IMidiManager.Stub {
     private int mNextDeviceId = 1;
 
     private final PackageManager mPackageManager;
+    private final UserManager mUserManager;
 
     private static final String MIDI_LEGACY_STRING = "MIDI 1.0";
     private static final String MIDI_UNIVERSAL_STRING = "MIDI 2.0";
@@ -159,21 +179,24 @@ public class MidiService extends IMidiManager.Stub {
     private final HashSet<ParcelUuid> mNonMidiUUIDs = new HashSet<ParcelUuid>();
 
     // PackageMonitor for listening to package changes
+    // uid is the uid of the package so use getChangingUserId() to fetch the userId.
     private final PackageMonitor mPackageMonitor = new PackageMonitor() {
         @Override
+        @RequiresPermission(Manifest.permission.INTERACT_ACROSS_USERS)
         public void onPackageAdded(String packageName, int uid) {
-            addPackageDeviceServers(packageName);
+            addPackageDeviceServers(packageName, getChangingUserId());
         }
 
         @Override
+        @RequiresPermission(Manifest.permission.INTERACT_ACROSS_USERS)
         public void onPackageModified(String packageName) {
-            removePackageDeviceServers(packageName);
-            addPackageDeviceServers(packageName);
+            removePackageDeviceServers(packageName, getChangingUserId());
+            addPackageDeviceServers(packageName, getChangingUserId());
         }
 
         @Override
         public void onPackageRemoved(String packageName, int uid) {
-            removePackageDeviceServers(packageName);
+            removePackageDeviceServers(packageName, getChangingUserId());
         }
     };
 
@@ -202,6 +225,10 @@ public class MidiService extends IMidiManager.Stub {
             return mUid;
         }
 
+        private int getUserId() {
+            return UserHandle.getUserId(mUid);
+        }
+
         public void addListener(IMidiDeviceListener listener) {
             if (mListeners.size() >= MAX_LISTENERS_PER_CLIENT) {
                 throw new SecurityException(
@@ -219,8 +246,12 @@ public class MidiService extends IMidiManager.Stub {
             }
         }
 
-        public void addDeviceConnection(Device device, IMidiDeviceOpenCallback callback) {
-            Log.d(TAG, "addDeviceConnection() device:" + device);
+        @RequiresPermission(anyOf = {Manifest.permission.INTERACT_ACROSS_USERS_FULL,
+                Manifest.permission.INTERACT_ACROSS_USERS,
+                Manifest.permission.INTERACT_ACROSS_PROFILES})
+        public void addDeviceConnection(Device device, IMidiDeviceOpenCallback callback,
+                int userId) {
+            Log.d(TAG, "addDeviceConnection() device:" + device + " userId:" + userId);
             if (mDeviceConnections.size() >= MAX_CONNECTIONS_PER_CLIENT) {
                 Log.i(TAG, "too many MIDI connections for UID = " + mUid);
                 throw new SecurityException(
@@ -228,7 +259,7 @@ public class MidiService extends IMidiManager.Stub {
             }
             DeviceConnection connection = new DeviceConnection(device, this, callback);
             mDeviceConnections.put(connection.getToken(), connection);
-            device.addDeviceConnection(connection);
+            device.addDeviceConnection(connection, userId);
         }
 
         // called from MidiService.closeDevice()
@@ -251,8 +282,8 @@ public class MidiService extends IMidiManager.Stub {
         }
 
         public void deviceAdded(Device device) {
-            // ignore private devices that our client cannot access
-            if (!device.isUidAllowed(mUid)) return;
+            // ignore devices that our client cannot access
+            if (!device.isUidAllowed(mUid) || !device.isUserIdAllowed(getUserId())) return;
 
             MidiDeviceInfo deviceInfo = device.getDeviceInfo();
             try {
@@ -265,8 +296,8 @@ public class MidiService extends IMidiManager.Stub {
         }
 
         public void deviceRemoved(Device device) {
-            // ignore private devices that our client cannot access
-            if (!device.isUidAllowed(mUid)) return;
+            // ignore devices that our client cannot access
+            if (!device.isUidAllowed(mUid) || !device.isUserIdAllowed(getUserId())) return;
 
             MidiDeviceInfo deviceInfo = device.getDeviceInfo();
             try {
@@ -279,8 +310,8 @@ public class MidiService extends IMidiManager.Stub {
         }
 
         public void deviceStatusChanged(Device device, MidiDeviceStatus status) {
-            // ignore private devices that our client cannot access
-            if (!device.isUidAllowed(mUid)) return;
+            // ignore devices that our client cannot access
+            if (!device.isUidAllowed(mUid) || !device.isUserIdAllowed(getUserId())) return;
 
             try {
                 for (IMidiDeviceListener listener : mListeners.values()) {
@@ -354,6 +385,8 @@ public class MidiService extends IMidiManager.Stub {
         private final ServiceInfo mServiceInfo;
         // UID of device implementation
         private final int mUid;
+        // User Id of the app. Only used for virtual devices
+        private final int mUserId;
 
         // ServiceConnection for implementing Service (virtual devices only)
         // mServiceConnection is non-null when connected or attempting to connect to the service
@@ -375,19 +408,24 @@ public class MidiService extends IMidiManager.Stub {
         private AtomicInteger mTotalOutputBytes = new AtomicInteger();
 
         public Device(IMidiDeviceServer server, MidiDeviceInfo deviceInfo,
-                ServiceInfo serviceInfo, int uid) {
+                ServiceInfo serviceInfo, int uid, int userId) {
             mDeviceInfo = deviceInfo;
             mServiceInfo = serviceInfo;
             mUid = uid;
+            mUserId = userId;
             mBluetoothDevice = (BluetoothDevice)deviceInfo.getProperties().getParcelable(
                     MidiDeviceInfo.PROPERTY_BLUETOOTH_DEVICE, android.bluetooth.BluetoothDevice.class);;
             setDeviceServer(server);
         }
 
+        @RequiresPermission(anyOf = {Manifest.permission.QUERY_USERS,
+                Manifest.permission.CREATE_USERS,
+                Manifest.permission.MANAGE_USERS})
         public Device(BluetoothDevice bluetoothDevice) {
             mBluetoothDevice = bluetoothDevice;
             mServiceInfo = null;
             mUid = mBluetoothServiceUid;
+            mUserId = mUserManager.getMainUser().getIdentifier();
         }
 
         private void setDeviceServer(IMidiDeviceServer server) {
@@ -468,11 +506,22 @@ public class MidiService extends IMidiManager.Stub {
             return mUid;
         }
 
+        public int getUserId() {
+            return mUserId;
+        }
+
         public boolean isUidAllowed(int uid) {
             return (!mDeviceInfo.isPrivate() || mUid == uid);
         }
 
-        public void addDeviceConnection(DeviceConnection connection) {
+        public boolean isUserIdAllowed(int userId) {
+            return (mDeviceInfo.getType() != MidiDeviceInfo.TYPE_VIRTUAL || mUserId == userId);
+        }
+
+        @RequiresPermission(anyOf = {Manifest.permission.INTERACT_ACROSS_USERS_FULL,
+                Manifest.permission.INTERACT_ACROSS_USERS,
+                Manifest.permission.INTERACT_ACROSS_PROFILES})
+        public void addDeviceConnection(DeviceConnection connection, int userId) {
             Log.d(TAG, "addDeviceConnection() [A] connection:" + connection);
             synchronized (mDeviceConnections) {
                 mDeviceConnectionsAdded.incrementAndGet();
@@ -537,8 +586,8 @@ public class MidiService extends IMidiManager.Stub {
                                 new ComponentName(mServiceInfo.packageName, mServiceInfo.name));
                     }
 
-                    if (!mContext.bindService(intent, mServiceConnection,
-                            Context.BIND_AUTO_CREATE)) {
+                    if (!mContext.bindServiceAsUser(intent, mServiceConnection,
+                            Context.BIND_AUTO_CREATE, UserHandle.of(mUserId))) {
                         Log.e(TAG, "Unable to bind service: " + intent);
                         setDeviceServer(null);
                         mServiceConnection = null;
@@ -886,6 +935,8 @@ public class MidiService extends IMidiManager.Stub {
     public MidiService(Context context) {
         mContext = context;
         mPackageManager = context.getPackageManager();
+        mUserManager = mContext.getSystemService(UserManager.class);
+        mPackageMonitor.register(mContext, null, UserHandle.ALL, true);
 
         // TEMPORARY - Disable BTL-MIDI
         //FIXME - b/25689266
@@ -913,32 +964,41 @@ public class MidiService extends IMidiManager.Stub {
         // mNonMidiUUIDs.add(BluetoothUuid.BATTERY);
     }
 
-    private void onUnlockUser() {
-        mPackageMonitor.register(mContext, null, true);
-
+    @RequiresPermission(allOf = {Manifest.permission.INTERACT_ACROSS_USERS},
+            anyOf = {Manifest.permission.QUERY_USERS,
+            Manifest.permission.CREATE_USERS,
+            Manifest.permission.MANAGE_USERS})
+    private void onStartOrUnlockUser(TargetUser user, boolean matchDirectBootUnaware) {
+        Log.d(TAG, "onStartOrUnlockUser " + user.getUserIdentifier() + " matchDirectBootUnaware: "
+                + matchDirectBootUnaware);
         Intent intent = new Intent(MidiDeviceService.SERVICE_INTERFACE);
-        List<ResolveInfo> resolveInfos = mPackageManager.queryIntentServices(intent,
-                PackageManager.GET_META_DATA);
+        int resolveFlags = PackageManager.GET_META_DATA;
+        if (matchDirectBootUnaware) {
+            resolveFlags |= PackageManager.MATCH_DIRECT_BOOT_UNAWARE;
+        }
+        List<ResolveInfo> resolveInfos = mPackageManager.queryIntentServicesAsUser(intent,
+                resolveFlags, user.getUserIdentifier());
         if (resolveInfos != null) {
             int count = resolveInfos.size();
             for (int i = 0; i < count; i++) {
                 ServiceInfo serviceInfo = resolveInfos.get(i).serviceInfo;
                 if (serviceInfo != null) {
-                    addPackageDeviceServer(serviceInfo);
+                    addPackageDeviceServer(serviceInfo, user.getUserIdentifier());
                 }
             }
         }
 
-        PackageInfo info;
-        try {
-            info = mPackageManager.getPackageInfo(MidiManager.BLUETOOTH_MIDI_SERVICE_PACKAGE, 0);
-        } catch (PackageManager.NameNotFoundException e) {
-            info = null;
-        }
-        if (info != null && info.applicationInfo != null) {
-            mBluetoothServiceUid = info.applicationInfo.uid;
-        } else {
-            mBluetoothServiceUid = -1;
+        if (user.getUserIdentifier() == mUserManager.getMainUser().getIdentifier()) {
+            PackageInfo info;
+            try {
+                info = mPackageManager.getPackageInfoAsUser(
+                        MidiManager.BLUETOOTH_MIDI_SERVICE_PACKAGE, 0, user.getUserIdentifier());
+            } catch (PackageManager.NameNotFoundException e) {
+                info = null;
+            }
+            if (info != null && info.applicationInfo != null) {
+                mBluetoothServiceUid = info.applicationInfo.uid;
+            }
         }
     }
 
@@ -960,10 +1020,11 @@ public class MidiService extends IMidiManager.Stub {
 
     // Inform listener of the status of all known devices.
     private void updateStickyDeviceStatus(int uid, IMidiDeviceListener listener) {
+        int userId = UserHandle.getUserId(uid);
         synchronized (mDevicesByInfo) {
             for (Device device : mDevicesByInfo.values()) {
-                // ignore private devices that our client cannot access
-                if (device.isUidAllowed(uid)) {
+                // ignore devices that our client cannot access
+                if (device.isUidAllowed(uid) && device.isUserIdAllowed(userId)) {
                     try {
                         MidiDeviceStatus status = device.getDeviceStatus();
                         if (status != null) {
@@ -989,10 +1050,11 @@ public class MidiService extends IMidiManager.Stub {
     public MidiDeviceInfo[] getDevicesForTransport(int transport) {
         ArrayList<MidiDeviceInfo> deviceInfos = new ArrayList<MidiDeviceInfo>();
         int uid = Binder.getCallingUid();
+        int userId = getCallingUserId();
 
         synchronized (mDevicesByInfo) {
             for (Device device : mDevicesByInfo.values()) {
-                if (device.isUidAllowed(uid)) {
+                if (device.isUidAllowed(uid) && device.isUserIdAllowed(userId)) {
                     // UMP devices have protocols that are not PROTOCOL_UNKNOWN
                     if (transport == MidiManager.TRANSPORT_UNIVERSAL_MIDI_PACKETS) {
                         if (device.getDeviceInfo().getDefaultProtocol()
@@ -1029,6 +1091,9 @@ public class MidiService extends IMidiManager.Stub {
             if (!device.isUidAllowed(Binder.getCallingUid())) {
                 throw new SecurityException("Attempt to open private device with wrong UID");
             }
+            if (!device.isUserIdAllowed(getCallingUserId())) {
+                throw new SecurityException("Attempt to open virtual device with wrong user id");
+            }
         }
 
         if (deviceInfo.getType() == MidiDeviceInfo.TYPE_USB) {
@@ -1044,7 +1109,7 @@ public class MidiService extends IMidiManager.Stub {
         final long identity = Binder.clearCallingIdentity();
         try {
             Log.i(TAG, "addDeviceConnection() [B] device:" + device);
-            client.addDeviceConnection(device, callback);
+            client.addDeviceConnection(device, callback, getCallingUserId());
         } finally {
             Binder.restoreCallingIdentity(identity);
         }
@@ -1106,7 +1171,7 @@ public class MidiService extends IMidiManager.Stub {
         final long identity = Binder.clearCallingIdentity();
         try {
             Log.i(TAG, "addDeviceConnection() [C] device:" + device);
-            client.addDeviceConnection(device, callback);
+            client.addDeviceConnection(device, callback, getCallingUserId());
         } finally {
             Binder.restoreCallingIdentity(identity);
         }
@@ -1124,6 +1189,7 @@ public class MidiService extends IMidiManager.Stub {
             int numOutputPorts, String[] inputPortNames, String[] outputPortNames,
             Bundle properties, int type, int defaultProtocol) {
         int uid = Binder.getCallingUid();
+        int userId = getCallingUserId();
         if (type == MidiDeviceInfo.TYPE_USB && uid != Process.SYSTEM_UID) {
             throw new SecurityException("only system can create USB devices");
         } else if (type == MidiDeviceInfo.TYPE_BLUETOOTH && uid != mBluetoothServiceUid) {
@@ -1133,7 +1199,7 @@ public class MidiService extends IMidiManager.Stub {
         synchronized (mDevicesByInfo) {
             return addDeviceLocked(type, numInputPorts, numOutputPorts, inputPortNames,
                     outputPortNames, properties, server, null, false, uid,
-                    defaultProtocol);
+                    defaultProtocol, userId);
         }
     }
 
@@ -1210,7 +1276,8 @@ public class MidiService extends IMidiManager.Stub {
     private MidiDeviceInfo addDeviceLocked(int type, int numInputPorts, int numOutputPorts,
             String[] inputPortNames, String[] outputPortNames, Bundle properties,
             IMidiDeviceServer server, ServiceInfo serviceInfo,
-            boolean isPrivate, int uid, int defaultProtocol) {
+            boolean isPrivate, int uid, int defaultProtocol, int userId) {
+        Log.d(TAG, "addDeviceLocked()" + uid + " type:" + type);
 
         // Limit the number of devices per app.
         int deviceCountForApp = 0;
@@ -1250,7 +1317,7 @@ public class MidiService extends IMidiManager.Stub {
             }
         }
         if (device == null) {
-            device = new Device(server, deviceInfo, serviceInfo, uid);
+            device = new Device(server, deviceInfo, serviceInfo, uid, userId);
         }
         mDevicesByInfo.put(deviceInfo, device);
         if (bluetoothDevice != null) {
@@ -1281,12 +1348,14 @@ public class MidiService extends IMidiManager.Stub {
         }
     }
 
-    private void addPackageDeviceServers(String packageName) {
+    @RequiresPermission(Manifest.permission.INTERACT_ACROSS_USERS)
+    private void addPackageDeviceServers(String packageName, int userId) {
         PackageInfo info;
 
         try {
-            info = mPackageManager.getPackageInfo(packageName,
-                    PackageManager.GET_SERVICES | PackageManager.GET_META_DATA);
+            info = mPackageManager.getPackageInfoAsUser(packageName,
+                    PackageManager.GET_SERVICES | PackageManager.GET_META_DATA
+                    | PackageManager.MATCH_DIRECT_BOOT_UNAWARE, userId);
         } catch (PackageManager.NameNotFoundException e) {
             Log.e(TAG, "handlePackageUpdate could not find package " + packageName, e);
             return;
@@ -1295,13 +1364,14 @@ public class MidiService extends IMidiManager.Stub {
         ServiceInfo[] services = info.services;
         if (services == null) return;
         for (int i = 0; i < services.length; i++) {
-            addPackageDeviceServer(services[i]);
+            addPackageDeviceServer(services[i], userId);
         }
     }
 
     private static final String[] EMPTY_STRING_ARRAY = new String[0];
 
-    private void addPackageDeviceServer(ServiceInfo serviceInfo) {
+    private void addPackageDeviceServer(ServiceInfo serviceInfo, int userId) {
+        Log.d(TAG, "addPackageDeviceServer()" + userId);
         XmlResourceParser parser = null;
 
         try {
@@ -1404,8 +1474,8 @@ public class MidiService extends IMidiManager.Stub {
 
                             int uid;
                             try {
-                                ApplicationInfo appInfo = mPackageManager.getApplicationInfo(
-                                        serviceInfo.packageName, 0);
+                                ApplicationInfo appInfo = mPackageManager.getApplicationInfoAsUser(
+                                        serviceInfo.packageName, 0, userId);
                                 uid = appInfo.uid;
                             } catch (PackageManager.NameNotFoundException e) {
                                 Log.e(TAG, "could not fetch ApplicationInfo for "
@@ -1419,7 +1489,7 @@ public class MidiService extends IMidiManager.Stub {
                                         inputPortNames.toArray(EMPTY_STRING_ARRAY),
                                         outputPortNames.toArray(EMPTY_STRING_ARRAY),
                                         properties, null, serviceInfo, isPrivate, uid,
-                                        MidiDeviceInfo.PROTOCOL_UNKNOWN);
+                                        MidiDeviceInfo.PROTOCOL_UNKNOWN, userId);
                             }
                             // setting properties to null signals that we are no longer
                             // processing a <device>
@@ -1437,12 +1507,13 @@ public class MidiService extends IMidiManager.Stub {
         }
     }
 
-    private void removePackageDeviceServers(String packageName) {
+    private void removePackageDeviceServers(String packageName, int userId) {
         synchronized (mDevicesByInfo) {
             Iterator<Device> iterator = mDevicesByInfo.values().iterator();
             while (iterator.hasNext()) {
                 Device device = iterator.next();
-                if (packageName.equals(device.getPackageName())) {
+                if (packageName.equals(device.getPackageName())
+                        && (device.getUserId() == userId)) {
                     iterator.remove();
                     removeDeviceLocked(device);
                 }
@@ -1571,4 +1642,11 @@ public class MidiService extends IMidiManager.Stub {
     String extractUsbDeviceTag(String propertyName) {
         return propertyName.substring(propertyName.length() - MIDI_LEGACY_STRING.length());
     }
+
+    /**
+     * @return the user id of the calling user.
+     */
+    private int getCallingUserId() {
+        return UserHandle.getUserId(Binder.getCallingUid());
+    }
 }