Add API to call to vold for mounting OBBs

* Unhide StorageService class; hide all the USB-related items

* Add application-visible API to StorageManager for OBB files

* Add class for parceling OBB info across binders (ObbInfo)

* Add a JNI glue class to libutils/ObbFile (ObbScanner)

* Add API to MountService to deal with calling into vold and checking
  permissions

Change-Id: I33ecf9606b8ff535f3a2ada83931da6bbef41cfd

12 files changed, 548 insertions, 10 deletions

diff --git a/api/current.xml b/api/current.xml
index 0626cd5..1ed5811 100644
--- a/api/current.xml
+++ b/api/current.xml
@@ -38302,6 +38302,17 @@
  visibility="public"
 >
 </field>
+<field name="STORAGE_SERVICE"
+ type="java.lang.String"
+ transient="false"
+ volatile="false"
+ value="&quot;storage&quot;"
+ static="true"
+ final="true"
+ deprecated="not deprecated"
+ visibility="public"
+>
+</field>
 <field name="TELEPHONY_SERVICE"
  type="java.lang.String"
  transient="false"
@@ -125618,6 +125629,74 @@
 </method>
 </class>
 </package>
+<package name="android.os.storage"
+>
+<class name="StorageManager"
+ extends="java.lang.Object"
+ abstract="false"
+ static="false"
+ final="false"
+ deprecated="not deprecated"
+ visibility="public"
+>
+<method name="getMountedObbPath"
+ return="java.lang.String"
+ abstract="false"
+ native="false"
+ synchronized="false"
+ static="false"
+ final="false"
+ deprecated="not deprecated"
+ visibility="public"
+>
+<parameter name="filename" type="java.lang.String">
+</parameter>
+</method>
+<method name="isObbMounted"
+ return="boolean"
+ abstract="false"
+ native="false"
+ synchronized="false"
+ static="false"
+ final="false"
+ deprecated="not deprecated"
+ visibility="public"
+>
+<parameter name="filename" type="java.lang.String">
+</parameter>
+</method>
+<method name="mountObb"
+ return="boolean"
+ abstract="false"
+ native="false"
+ synchronized="false"
+ static="false"
+ final="false"
+ deprecated="not deprecated"
+ visibility="public"
+>
+<parameter name="filename" type="java.lang.String">
+</parameter>
+<parameter name="key" type="java.lang.String">
+</parameter>
+</method>
+<method name="unmountObb"
+ return="boolean"
+ abstract="false"
+ native="false"
+ synchronized="false"
+ static="false"
+ final="false"
+ deprecated="not deprecated"
+ visibility="public"
+>
+<parameter name="filename" type="java.lang.String">
+</parameter>
+<parameter name="force" type="boolean">
+</parameter>
+</method>
+</class>
+</package>
 <package name="android.preference"
 >
 <class name="CheckBoxPreference"
diff --git a/core/java/android/content/Context.java b/core/java/android/content/Context.java
index a14bd8f..e3b7731 100644
--- a/core/java/android/content/Context.java
+++ b/core/java/android/content/Context.java
@@ -1372,9 +1372,8 @@ public abstract class Context {
     public static final String SENSOR_SERVICE = "sensor";
     
     /**
-     * @hide
      * Use with {@link #getSystemService} to retrieve a {@link
-     * android.os.storage.StorageManager} for accesssing system storage
+     * android.os.storage.StorageManager} for accessing system storage
      * functions.
      *
      * @see #getSystemService
diff --git a/core/java/android/content/res/ObbInfo.aidl b/core/java/android/content/res/ObbInfo.aidl
new file mode 100755
index 0000000..636ad6a
--- /dev/null
+++ b/core/java/android/content/res/ObbInfo.aidl
@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2010 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.
+ */
+
+package android.content.res;
+
+parcelable ObbInfo;
diff --git a/core/java/android/content/res/ObbInfo.java b/core/java/android/content/res/ObbInfo.java
new file mode 100644
index 0000000..b18d784
--- /dev/null
+++ b/core/java/android/content/res/ObbInfo.java
@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2010 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.
+ */
+
+package android.content.res;
+
+import android.os.Parcel;
+import android.os.Parcelable;
+
+/**
+ * Basic information about a Opaque Binary Blob (OBB) that reflects
+ * the info from the footer on the OBB file.
+ * @hide
+ */
+public class ObbInfo implements Parcelable {
+    /**
+     * The name of the package to which the OBB file belongs.
+     */
+    public String packageName;
+
+    /**
+     * The version of the package to which the OBB file belongs.
+     */
+    public int version;
+
+    public ObbInfo() {
+    }
+
+    public String toString() {
+        return "ObbInfo{"
+            + Integer.toHexString(System.identityHashCode(this))
+            + " packageName=" + packageName + ",version=" + version + "}";
+    }
+
+    public int describeContents() {
+        return 0;
+    }
+
+    public void writeToParcel(Parcel dest, int parcelableFlags) {
+        dest.writeString(packageName);
+        dest.writeInt(version);
+    }
+
+    public static final Parcelable.Creator<ObbInfo> CREATOR
+            = new Parcelable.Creator<ObbInfo>() {
+        public ObbInfo createFromParcel(Parcel source) {
+            return new ObbInfo(source);
+        }
+
+        public ObbInfo[] newArray(int size) {
+            return new ObbInfo[size];
+        }
+    };
+
+    private ObbInfo(Parcel source) {
+        packageName = source.readString();
+        version = source.readInt();
+    }
+}
diff --git a/core/java/android/content/res/ObbScanner.java b/core/java/android/content/res/ObbScanner.java
new file mode 100644
index 0000000..eb383c3
--- /dev/null
+++ b/core/java/android/content/res/ObbScanner.java
@@ -0,0 +1,40 @@
+/*
+ * Copyright (C) 2010 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.
+ */
+
+package android.content.res;
+
+/**
+ * Class to scan Opaque Binary Blob (OBB) files.
+ * @hide
+ */
+public class ObbScanner {
+    // Don't allow others to instantiate this class
+    private ObbScanner() {}
+
+    public static ObbInfo getObbInfo(String filePath) {
+        if (filePath == null) {
+            return null;
+        }
+
+        ObbInfo obbInfo = new ObbInfo();
+        if (!getObbInfo_native(filePath, obbInfo)) {
+            throw new IllegalArgumentException("Could not read OBB file: " + filePath);
+        }
+        return obbInfo;
+    }
+
+    private native static boolean getObbInfo_native(String filePath, ObbInfo obbInfo);
+}
diff --git a/core/java/android/os/storage/IMountService.aidl b/core/java/android/os/storage/IMountService.aidl
index 4862f80..ca7efe7 100644
--- a/core/java/android/os/storage/IMountService.aidl
+++ b/core/java/android/os/storage/IMountService.aidl
@@ -152,4 +152,26 @@ interface IMountService
      * processing the media status update request.
      */
     void finishMediaUpdate();
+
+    /**
+     * Mounts an Opaque Binary Blob (OBB) with the specified decryption key and only
+     * allows the calling process's UID access to the contents.
+     */
+    int mountObb(String filename, String key);
+
+    /**
+     * Unmounts an Opaque Binary Blob (OBB). When the force flag is specified, any
+     * program using it will be forcibly killed to unmount the image.
+     */
+    int unmountObb(String filename, boolean force);
+
+    /**
+     * Checks whether the specified Opaque Binary Blob (OBB) is mounted somewhere.
+     */
+    boolean isObbMounted(String filename);
+
+    /**
+     * Gets the path to the mounted Opaque Binary Blob (OBB).
+     */
+    String getMountedObbPath(String filename);
 }
diff --git a/core/java/android/os/storage/StorageManager.java b/core/java/android/os/storage/StorageManager.java
index a12603c..96bf2d5 100644
--- a/core/java/android/os/storage/StorageManager.java
+++ b/core/java/android/os/storage/StorageManager.java
@@ -44,9 +44,6 @@ import java.util.List;
  * Get an instance of this class by calling
  * {@link android.content.Context#getSystemService(java.lang.String)} with an argument
  * of {@link android.content.Context#STORAGE_SERVICE}.
- *
- * @hide
- *
  */
 
 public class StorageManager
@@ -209,6 +206,7 @@ public class StorageManager
      *
      * @param listener A {@link android.os.storage.StorageEventListener StorageEventListener} object.
      *
+     * @hide
      */
     public void registerListener(StorageEventListener listener) {
         if (listener == null) {
@@ -225,6 +223,7 @@ public class StorageManager
      *
      * @param listener A {@link android.os.storage.StorageEventListener StorageEventListener} object.
      *
+     * @hide
      */
     public void unregisterListener(StorageEventListener listener) {
         if (listener == null) {
@@ -245,6 +244,8 @@ public class StorageManager
 
     /**
      * Enables USB Mass Storage (UMS) on the device.
+     *
+     * @hide
      */
     public void enableUsbMassStorage() {
         try {
@@ -256,6 +257,8 @@ public class StorageManager
 
     /**
      * Disables USB Mass Storage (UMS) on the device.
+     *
+     * @hide
      */
     public void disableUsbMassStorage() {
         try {
@@ -268,6 +271,8 @@ public class StorageManager
     /**
      * Query if a USB Mass Storage (UMS) host is connected.
      * @return true if UMS host is connected.
+     *
+     * @hide
      */
     public boolean isUsbMassStorageConnected() {
         try {
@@ -281,6 +286,8 @@ public class StorageManager
     /**
      * Query if a USB Mass Storage (UMS) is enabled on the device.
      * @return true if UMS host is enabled.
+     *
+     * @hide
      */
     public boolean isUsbMassStorageEnabled() {
         try {
@@ -290,4 +297,55 @@ public class StorageManager
         }
         return false;
     }
+
+    /**
+     * Mount an OBB file.
+     */
+    public boolean mountObb(String filename, String key) {
+        try {
+            return mMountService.mountObb(filename, key)
+                    == StorageResultCode.OperationSucceeded;
+        } catch (RemoteException e) {
+            Log.e(TAG, "Failed to mount OBB", e);
+        }
+
+        return false;
+    }
+
+    /**
+     * Mount an OBB file.
+     */
+    public boolean unmountObb(String filename, boolean force) {
+        try {
+            return mMountService.unmountObb(filename, force)
+                    == StorageResultCode.OperationSucceeded;
+        } catch (RemoteException e) {
+            Log.e(TAG, "Failed to mount OBB", e);
+        }
+
+        return false;
+    }
+
+    public boolean isObbMounted(String filename) {
+        try {
+            return mMountService.isObbMounted(filename);
+        } catch (RemoteException e) {
+            Log.e(TAG, "Failed to check if OBB is mounted", e);
+        }
+
+        return false;
+    }
+
+    /**
+     * Check the mounted path of an OBB file.
+     */
+    public String getMountedObbPath(String filename) {
+        try {
+            return mMountService.getMountedObbPath(filename);
+        } catch (RemoteException e) {
+            Log.e(TAG, "Failed to find mounted path for OBB", e);
+        }
+
+        return null;
+    }
 }
diff --git a/core/java/com/android/internal/app/IMediaContainerService.aidl b/core/java/com/android/internal/app/IMediaContainerService.aidl
index 0f817b7..a59c14b 100755
--- a/core/java/com/android/internal/app/IMediaContainerService.aidl
+++ b/core/java/com/android/internal/app/IMediaContainerService.aidl
@@ -19,6 +19,7 @@ package com.android.internal.app;
 import android.net.Uri;
 import android.os.ParcelFileDescriptor;
 import android.content.pm.PackageInfoLite;
+import android.content.res.ObbInfo;
 
 interface IMediaContainerService {
     String copyResourceToContainer(in Uri packageURI,
@@ -28,4 +29,5 @@ interface IMediaContainerService {
                 in ParcelFileDescriptor outStream);
     PackageInfoLite getMinimalPackageInfo(in Uri fileUri, int flags);
     boolean checkFreeStorage(boolean external, in Uri fileUri);
-}
\ No newline at end of file
+    ObbInfo getObbInfo(in Uri fileUri);
+}
diff --git a/core/jni/Android.mk b/core/jni/Android.mk
index 468f844..89fea41 100644
--- a/core/jni/Android.mk
+++ b/core/jni/Android.mk
@@ -134,7 +134,8 @@ LOCAL_SRC_FILES:= \
 	android_backup_BackupDataInput.cpp \
 	android_backup_BackupDataOutput.cpp \
 	android_backup_FileBackupHelperBase.cpp \
-	android_backup_BackupHelperDispatcher.cpp
+	android_backup_BackupHelperDispatcher.cpp \
+	android_content_res_ObbScanner.cpp
 
 LOCAL_C_INCLUDES += \
 	$(JNI_H_INCLUDE) \
diff --git a/core/jni/AndroidRuntime.cpp b/core/jni/AndroidRuntime.cpp
index 6fb1369..fc1f488 100644
--- a/core/jni/AndroidRuntime.cpp
+++ b/core/jni/AndroidRuntime.cpp
@@ -166,6 +166,7 @@ extern int register_android_view_InputChannel(JNIEnv* env);
 extern int register_android_view_InputQueue(JNIEnv* env);
 extern int register_android_view_KeyEvent(JNIEnv* env);
 extern int register_android_view_MotionEvent(JNIEnv* env);
+extern int register_android_content_res_ObbScanner(JNIEnv* env);
 
 static AndroidRuntime* gCurRuntime = NULL;
 
@@ -1298,6 +1299,8 @@ static const RegJNIRec gRegJNI[] = {
     REG_JNI(register_android_view_InputQueue),
     REG_JNI(register_android_view_KeyEvent),
     REG_JNI(register_android_view_MotionEvent),
+
+    REG_JNI(register_android_content_res_ObbScanner),
 };
 
 /*
diff --git a/core/jni/android_content_res_ObbScanner.cpp b/core/jni/android_content_res_ObbScanner.cpp
new file mode 100644
index 0000000..1239274
--- /dev/null
+++ b/core/jni/android_content_res_ObbScanner.cpp
@@ -0,0 +1,94 @@
+/*
+ * Copyright 2010, 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.
+ */
+
+#define LOG_TAG "ObbScanner"
+
+#include <utils/Log.h>
+#include <utils/String8.h>
+#include <utils/ObbFile.h>
+
+#include "jni.h"
+#include "utils/misc.h"
+#include "android_runtime/AndroidRuntime.h"
+
+namespace android {
+
+static struct {
+    jclass clazz;
+
+    jfieldID packageName;
+    jfieldID version;
+} gObbInfoClassInfo;
+
+static jboolean android_content_res_ObbScanner_getObbInfo(JNIEnv* env, jobject clazz, jstring file,
+        jobject obbInfo)
+{
+    const char* filePath = env->GetStringUTFChars(file, JNI_FALSE);
+
+    sp<ObbFile> obb = new ObbFile();
+    if (!obb->readFrom(filePath)) {
+        env->ReleaseStringUTFChars(file, filePath);
+        return JNI_FALSE;
+    }
+
+    env->ReleaseStringUTFChars(file, filePath);
+
+    const char* packageNameStr = obb->getPackageName().string();
+
+    jstring packageName = env->NewStringUTF(packageNameStr);
+    if (packageName == NULL) {
+        return JNI_FALSE;
+    }
+
+    env->SetObjectField(obbInfo, gObbInfoClassInfo.packageName, packageName);
+    env->SetIntField(obbInfo, gObbInfoClassInfo.version, obb->getVersion());
+
+    return JNI_TRUE;
+}
+
+/*
+ * JNI registration.
+ */
+static JNINativeMethod gMethods[] = {
+    /* name, signature, funcPtr */
+    { "getObbInfo_native", "(Ljava/lang/String;Landroid/content/res/ObbInfo;)Z",
+            (void*) android_content_res_ObbScanner_getObbInfo },
+};
+
+#define FIND_CLASS(var, className) \
+        var = env->FindClass(className); \
+        LOG_FATAL_IF(! var, "Unable to find class " className); \
+        var = jclass(env->NewGlobalRef(var));
+
+#define GET_FIELD_ID(var, clazz, fieldName, fieldDescriptor) \
+        var = env->GetFieldID(clazz, fieldName, fieldDescriptor); \
+        LOG_FATAL_IF(! var, "Unable to find field " fieldName);
+
+int register_android_content_res_ObbScanner(JNIEnv* env)
+{
+    FIND_CLASS(gObbInfoClassInfo.clazz, "android/content/res/ObbInfo");
+
+    GET_FIELD_ID(gObbInfoClassInfo.packageName, gObbInfoClassInfo.clazz,
+            "packageName", "Ljava/lang/String;");
+    GET_FIELD_ID(gObbInfoClassInfo.version, gObbInfoClassInfo.clazz,
+            "version", "I");
+
+    return AndroidRuntime::registerNativeMethods(env, "android/content/res/ObbScanner", gMethods,
+            NELEM(gMethods));
+}
+
+}; // namespace android
+
diff --git a/services/java/com/android/server/MountService.java b/services/java/com/android/server/MountService.java
index 6c2f1b2..d7b92ec 100644
--- a/services/java/com/android/server/MountService.java
+++ b/services/java/com/android/server/MountService.java
@@ -23,11 +23,14 @@ import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
 import android.content.pm.PackageManager;
+import android.content.res.ObbInfo;
+import android.content.res.ObbScanner;
 import android.net.Uri;
 import android.os.storage.IMountService;
 import android.os.storage.IMountServiceListener;
 import android.os.storage.IMountShutdownObserver;
 import android.os.storage.StorageResultCode;
+import android.os.Binder;
 import android.os.Handler;
 import android.os.HandlerThread;
 import android.os.Looper;
@@ -53,7 +56,8 @@ class MountService extends IMountService.Stub
     private static final boolean LOCAL_LOGD = false;
     private static final boolean DEBUG_UNMOUNT = false;
     private static final boolean DEBUG_EVENTS = false;
-    
+    private static final boolean DEBUG_OBB = true;
+
     private static final String TAG = "MountService";
 
     /*
@@ -130,6 +134,12 @@ class MountService extends IMountService.Stub
      */
     final private HashSet<String> mAsecMountSet = new HashSet<String>();
 
+    /**
+     * Private hash of currently mounted filesystem images.
+     */
+    final private HashSet<String> mObbMountSet = new HashSet<String>();
+
+    // Handler messages
     private static final int H_UNMOUNT_PM_UPDATE = 1;
     private static final int H_UNMOUNT_PM_DONE = 2;
     private static final int H_UNMOUNT_MS = 3;
@@ -287,7 +297,7 @@ class MountService extends IMountService.Stub
             Slog.w(TAG, "Waiting too long for mReady!");
         }
     }
-  
+
     private BroadcastReceiver mBroadcastReceiver = new BroadcastReceiver() {
         public void onReceive(Context context, Intent intent) {
             String action = intent.getAction();
@@ -344,7 +354,7 @@ class MountService extends IMountService.Stub
 
         MountServiceBinderListener(IMountServiceListener listener) {
             mListener = listener;
- 
+
         }
 
         public void binderDied() {
@@ -1327,5 +1337,145 @@ class MountService extends IMountService.Stub
     public void finishMediaUpdate() {
         mHandler.sendEmptyMessage(H_UNMOUNT_PM_DONE);
     }
+
+    private boolean isCallerOwnerOfPackage(String packageName) {
+        final int callerUid = Binder.getCallingUid();
+        return isUidOwnerOfPackage(packageName, callerUid);
+    }
+
+    private boolean isUidOwnerOfPackage(String packageName, int callerUid) {
+        if (packageName == null) {
+            return false;
+        }
+
+        final int packageUid = mPms.getPackageUid(packageName);
+
+        if (DEBUG_OBB) {
+            Slog.d(TAG, "packageName = " + packageName + ", packageUid = " +
+                    packageUid + ", callerUid = " + callerUid);
+        }
+
+        return callerUid == packageUid;
+    }
+
+    public String getMountedObbPath(String filename) {
+        waitForReady();
+        warnOnNotMounted();
+
+        // XXX replace with call to IMediaContainerService
+        ObbInfo obbInfo = ObbScanner.getObbInfo(filename);
+        if (!isCallerOwnerOfPackage(obbInfo.packageName)) {
+            throw new IllegalArgumentException("Caller package does not match OBB file");
+        }
+
+        try {
+            ArrayList<String> rsp = mConnector.doCommand(String.format("obb path %s", filename));
+            String []tok = rsp.get(0).split(" ");
+            int code = Integer.parseInt(tok[0]);
+            if (code != VoldResponseCode.AsecPathResult) {
+                throw new IllegalStateException(String.format("Unexpected response code %d", code));
+            }
+            return tok[1];
+        } catch (NativeDaemonConnectorException e) {
+            int code = e.getCode();
+            if (code == VoldResponseCode.OpFailedStorageNotFound) {
+                throw new IllegalArgumentException(String.format("OBB '%s' not found", filename));
+            } else {
+                throw new IllegalStateException(String.format("Unexpected response code %d", code));
+            }
+        }
+    }
+
+    public boolean isObbMounted(String filename) {
+        waitForReady();
+        warnOnNotMounted();
+
+        // XXX replace with call to IMediaContainerService
+        ObbInfo obbInfo = ObbScanner.getObbInfo(filename);
+        if (!isCallerOwnerOfPackage(obbInfo.packageName)) {
+            throw new IllegalArgumentException("Caller package does not match OBB file");
+        }
+
+        synchronized (mObbMountSet) {
+            return mObbMountSet.contains(filename);
+        }
+    }
+
+    public int mountObb(String filename, String key) {
+        waitForReady();
+        warnOnNotMounted();
+
+        synchronized (mObbMountSet) {
+            if (mObbMountSet.contains(filename)) {
+                return StorageResultCode.OperationFailedStorageMounted;
+            }
+        }
+
+        final int callerUid = Binder.getCallingUid();
+
+        // XXX replace with call to IMediaContainerService
+        ObbInfo obbInfo = ObbScanner.getObbInfo(filename);
+        if (!isUidOwnerOfPackage(obbInfo.packageName, callerUid)) {
+            throw new IllegalArgumentException("Caller package does not match OBB file");
+        }
+
+        if (key == null) {
+            key = "none";
+        }
+
+        int rc = StorageResultCode.OperationSucceeded;
+        String cmd = String.format("obb mount %s %s %d", filename, key, callerUid);
+        try {
+            mConnector.doCommand(cmd);
+        } catch (NativeDaemonConnectorException e) {
+            int code = e.getCode();
+            if (code != VoldResponseCode.OpFailedStorageBusy) {
+                rc = StorageResultCode.OperationFailedInternalError;
+            }
+        }
+
+        if (rc == StorageResultCode.OperationSucceeded) {
+            synchronized (mObbMountSet) {
+                mObbMountSet.add(filename);
+            }
+        }
+        return rc;
+    }
+
+    public int unmountObb(String filename, boolean force) {
+        waitForReady();
+        warnOnNotMounted();
+
+        ObbInfo obbInfo = ObbScanner.getObbInfo(filename);
+        if (!isCallerOwnerOfPackage(obbInfo.packageName)) {
+            throw new IllegalArgumentException("Caller package does not match OBB file");
+        }
+
+        synchronized (mObbMountSet) {
+            if (!mObbMountSet.contains(filename)) {
+                return StorageResultCode.OperationFailedStorageNotMounted;
+            }
+         }
+
+        int rc = StorageResultCode.OperationSucceeded;
+        String cmd = String.format("obb unmount %s%s", filename, (force ? " force" : ""));
+        try {
+            mConnector.doCommand(cmd);
+        } catch (NativeDaemonConnectorException e) {
+            int code = e.getCode();
+            if (code == VoldResponseCode.OpFailedStorageBusy) {
+                rc = StorageResultCode.OperationFailedStorageBusy;
+            } else {
+                rc = StorageResultCode.OperationFailedInternalError;
+            }
+        }
+
+        if (rc == StorageResultCode.OperationSucceeded) {
+            synchronized (mObbMountSet) {
+                mObbMountSet.remove(filename);
+            }
+        }
+        return rc;
+    }
 }