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 package android.os.storage; 18 19 import android.os.Environment; 20 import android.os.Handler; 21 import android.os.Looper; 22 import android.os.Message; 23 import android.os.Parcelable; 24 import android.os.RemoteException; 25 import android.os.ServiceManager; 26 import android.util.Log; 27 import android.util.SparseArray; 28 29 import java.lang.ref.WeakReference; 30 import java.util.ArrayList; 31 import java.util.List; 32 import java.util.concurrent.atomic.AtomicInteger; 33 34 /** 35 * StorageManager is the interface to the systems storage service. The storage 36 * manager handles storage-related items such as Opaque Binary Blobs (OBBs). 37 * <p> 38 * OBBs contain a filesystem that maybe be encrypted on disk and mounted 39 * on-demand from an application. OBBs are a good way of providing large amounts 40 * of binary assets without packaging them into APKs as they may be multiple 41 * gigabytes in size. However, due to their size, they're most likely stored in 42 * a shared storage pool accessible from all programs. The system does not 43 * guarantee the security of the OBB file itself: if any program modifies the 44 * OBB, there is no guarantee that a read from that OBB will produce the 45 * expected output. 46 * <p> 47 * Get an instance of this class by calling 48 * {@link android.content.Context#getSystemService(java.lang.String)} with an 49 * argument of {@link android.content.Context#STORAGE_SERVICE}. 50 */ 51 52 public class StorageManager 53 { 54 private static final String TAG = "StorageManager"; 55 56 /* 57 * Our internal MountService binder reference 58 */ 59 private IMountService mMountService; 60 61 /* 62 * The looper target for callbacks 63 */ 64 Looper mTgtLooper; 65 66 /* 67 * Target listener for binder callbacks 68 */ 69 private MountServiceBinderListener mBinderListener; 70 71 /* 72 * List of our listeners 73 */ 74 private List<ListenerDelegate> mListeners = new ArrayList<ListenerDelegate>(); 75 76 /* 77 * Next available nonce 78 */ 79 final private AtomicInteger mNextNonce = new AtomicInteger(0); 80 81 private class MountServiceBinderListener extends IMountServiceListener.Stub { 82 public void onUsbMassStorageConnectionChanged(boolean available) { 83 final int size = mListeners.size(); 84 for (int i = 0; i < size; i++) { 85 mListeners.get(i).sendShareAvailabilityChanged(available); 86 } 87 } 88 89 public void onStorageStateChanged(String path, String oldState, String newState) { 90 final int size = mListeners.size(); 91 for (int i = 0; i < size; i++) { 92 mListeners.get(i).sendStorageStateChanged(path, oldState, newState); 93 } 94 } 95 } 96 97 /** 98 * Binder listener for OBB action results. 99 */ 100 private final ObbActionListener mObbActionListener = new ObbActionListener(); 101 102 private class ObbActionListener extends IObbActionListener.Stub { 103 @SuppressWarnings("hiding") 104 private SparseArray<ObbListenerDelegate> mListeners = new SparseArray<ObbListenerDelegate>(); 105 106 @Override 107 public void onObbResult(String filename, int nonce, int status) { 108 final ObbListenerDelegate delegate; 109 synchronized (mListeners) { 110 delegate = mListeners.get(nonce); 111 if (delegate != null) { 112 mListeners.remove(nonce); 113 } 114 } 115 116 if (delegate != null) { 117 delegate.sendObbStateChanged(filename, status); 118 } 119 } 120 121 public int addListener(OnObbStateChangeListener listener) { 122 final ObbListenerDelegate delegate = new ObbListenerDelegate(listener); 123 124 synchronized (mListeners) { 125 mListeners.put(delegate.nonce, delegate); 126 } 127 128 return delegate.nonce; 129 } 130 } 131 132 private int getNextNonce() { 133 return mNextNonce.getAndIncrement(); 134 } 135 136 /** 137 * Private class containing sender and receiver code for StorageEvents. 138 */ 139 private class ObbListenerDelegate { 140 private final WeakReference<OnObbStateChangeListener> mObbEventListenerRef; 141 private final Handler mHandler; 142 143 private final int nonce; 144 145 ObbListenerDelegate(OnObbStateChangeListener listener) { 146 nonce = getNextNonce(); 147 mObbEventListenerRef = new WeakReference<OnObbStateChangeListener>(listener); 148 mHandler = new Handler(mTgtLooper) { 149 @Override 150 public void handleMessage(Message msg) { 151 final OnObbStateChangeListener changeListener = getListener(); 152 if (changeListener == null) { 153 return; 154 } 155 156 StorageEvent e = (StorageEvent) msg.obj; 157 158 if (msg.what == StorageEvent.EVENT_OBB_STATE_CHANGED) { 159 ObbStateChangedStorageEvent ev = (ObbStateChangedStorageEvent) e; 160 changeListener.onObbStateChange(ev.path, ev.state); 161 } else { 162 Log.e(TAG, "Unsupported event " + msg.what); 163 } 164 } 165 }; 166 } 167 168 OnObbStateChangeListener getListener() { 169 if (mObbEventListenerRef == null) { 170 return null; 171 } 172 return mObbEventListenerRef.get(); 173 } 174 175 void sendObbStateChanged(String path, int state) { 176 ObbStateChangedStorageEvent e = new ObbStateChangedStorageEvent(path, state); 177 mHandler.sendMessage(e.getMessage()); 178 } 179 } 180 181 /** 182 * Message sent during an OBB status change event. 183 */ 184 private class ObbStateChangedStorageEvent extends StorageEvent { 185 public final String path; 186 187 public final int state; 188 189 public ObbStateChangedStorageEvent(String path, int state) { 190 super(EVENT_OBB_STATE_CHANGED); 191 this.path = path; 192 this.state = state; 193 } 194 } 195 196 /** 197 * Private base class for messages sent between the callback thread 198 * and the target looper handler. 199 */ 200 private class StorageEvent { 201 static final int EVENT_UMS_CONNECTION_CHANGED = 1; 202 static final int EVENT_STORAGE_STATE_CHANGED = 2; 203 static final int EVENT_OBB_STATE_CHANGED = 3; 204 205 private Message mMessage; 206 207 public StorageEvent(int what) { 208 mMessage = Message.obtain(); 209 mMessage.what = what; 210 mMessage.obj = this; 211 } 212 213 public Message getMessage() { 214 return mMessage; 215 } 216 } 217 218 /** 219 * Message sent on a USB mass storage connection change. 220 */ 221 private class UmsConnectionChangedStorageEvent extends StorageEvent { 222 public boolean available; 223 224 public UmsConnectionChangedStorageEvent(boolean a) { 225 super(EVENT_UMS_CONNECTION_CHANGED); 226 available = a; 227 } 228 } 229 230 /** 231 * Message sent on volume state change. 232 */ 233 private class StorageStateChangedStorageEvent extends StorageEvent { 234 public String path; 235 public String oldState; 236 public String newState; 237 238 public StorageStateChangedStorageEvent(String p, String oldS, String newS) { 239 super(EVENT_STORAGE_STATE_CHANGED); 240 path = p; 241 oldState = oldS; 242 newState = newS; 243 } 244 } 245 246 /** 247 * Private class containing sender and receiver code for StorageEvents. 248 */ 249 private class ListenerDelegate { 250 final StorageEventListener mStorageEventListener; 251 private final Handler mHandler; 252 253 ListenerDelegate(StorageEventListener listener) { 254 mStorageEventListener = listener; 255 mHandler = new Handler(mTgtLooper) { 256 @Override 257 public void handleMessage(Message msg) { 258 StorageEvent e = (StorageEvent) msg.obj; 259 260 if (msg.what == StorageEvent.EVENT_UMS_CONNECTION_CHANGED) { 261 UmsConnectionChangedStorageEvent ev = (UmsConnectionChangedStorageEvent) e; 262 mStorageEventListener.onUsbMassStorageConnectionChanged(ev.available); 263 } else if (msg.what == StorageEvent.EVENT_STORAGE_STATE_CHANGED) { 264 StorageStateChangedStorageEvent ev = (StorageStateChangedStorageEvent) e; 265 mStorageEventListener.onStorageStateChanged(ev.path, ev.oldState, ev.newState); 266 } else { 267 Log.e(TAG, "Unsupported event " + msg.what); 268 } 269 } 270 }; 271 } 272 273 StorageEventListener getListener() { 274 return mStorageEventListener; 275 } 276 277 void sendShareAvailabilityChanged(boolean available) { 278 UmsConnectionChangedStorageEvent e = new UmsConnectionChangedStorageEvent(available); 279 mHandler.sendMessage(e.getMessage()); 280 } 281 282 void sendStorageStateChanged(String path, String oldState, String newState) { 283 StorageStateChangedStorageEvent e = new StorageStateChangedStorageEvent(path, oldState, newState); 284 mHandler.sendMessage(e.getMessage()); 285 } 286 } 287 288 /** 289 * Constructs a StorageManager object through which an application can 290 * can communicate with the systems mount service. 291 * 292 * @param tgtLooper The {@android.os.Looper} which events will be received on. 293 * 294 * <p>Applications can get instance of this class by calling 295 * {@link android.content.Context#getSystemService(java.lang.String)} with an argument 296 * of {@link android.content.Context#STORAGE_SERVICE}. 297 * 298 * @hide 299 */ 300 public StorageManager(Looper tgtLooper) throws RemoteException { 301 mMountService = IMountService.Stub.asInterface(ServiceManager.getService("mount")); 302 if (mMountService == null) { 303 Log.e(TAG, "Unable to connect to mount service! - is it running yet?"); 304 return; 305 } 306 mTgtLooper = tgtLooper; 307 mBinderListener = new MountServiceBinderListener(); 308 mMountService.registerListener(mBinderListener); 309 } 310 311 312 /** 313 * Registers a {@link android.os.storage.StorageEventListener StorageEventListener}. 314 * 315 * @param listener A {@link android.os.storage.StorageEventListener StorageEventListener} object. 316 * 317 * @hide 318 */ 319 public void registerListener(StorageEventListener listener) { 320 if (listener == null) { 321 return; 322 } 323 324 synchronized (mListeners) { 325 mListeners.add(new ListenerDelegate(listener)); 326 } 327 } 328 329 /** 330 * Unregisters a {@link android.os.storage.StorageEventListener StorageEventListener}. 331 * 332 * @param listener A {@link android.os.storage.StorageEventListener StorageEventListener} object. 333 * 334 * @hide 335 */ 336 public void unregisterListener(StorageEventListener listener) { 337 if (listener == null) { 338 return; 339 } 340 341 synchronized (mListeners) { 342 final int size = mListeners.size(); 343 for (int i=0 ; i<size ; i++) { 344 ListenerDelegate l = mListeners.get(i); 345 if (l.getListener() == listener) { 346 mListeners.remove(i); 347 break; 348 } 349 } 350 } 351 } 352 353 /** 354 * Enables USB Mass Storage (UMS) on the device. 355 * 356 * @hide 357 */ 358 public void enableUsbMassStorage() { 359 try { 360 mMountService.setUsbMassStorageEnabled(true); 361 } catch (Exception ex) { 362 Log.e(TAG, "Failed to enable UMS", ex); 363 } 364 } 365 366 /** 367 * Disables USB Mass Storage (UMS) on the device. 368 * 369 * @hide 370 */ 371 public void disableUsbMassStorage() { 372 try { 373 mMountService.setUsbMassStorageEnabled(false); 374 } catch (Exception ex) { 375 Log.e(TAG, "Failed to disable UMS", ex); 376 } 377 } 378 379 /** 380 * Query if a USB Mass Storage (UMS) host is connected. 381 * @return true if UMS host is connected. 382 * 383 * @hide 384 */ 385 public boolean isUsbMassStorageConnected() { 386 try { 387 return mMountService.isUsbMassStorageConnected(); 388 } catch (Exception ex) { 389 Log.e(TAG, "Failed to get UMS connection state", ex); 390 } 391 return false; 392 } 393 394 /** 395 * Query if a USB Mass Storage (UMS) is enabled on the device. 396 * @return true if UMS host is enabled. 397 * 398 * @hide 399 */ 400 public boolean isUsbMassStorageEnabled() { 401 try { 402 return mMountService.isUsbMassStorageEnabled(); 403 } catch (RemoteException rex) { 404 Log.e(TAG, "Failed to get UMS enable state", rex); 405 } 406 return false; 407 } 408 409 /** 410 * Mount an Opaque Binary Blob (OBB) file. If a <code>key</code> is 411 * specified, it is supplied to the mounting process to be used in any 412 * encryption used in the OBB. 413 * <p> 414 * The OBB will remain mounted for as long as the StorageManager reference 415 * is held by the application. As soon as this reference is lost, the OBBs 416 * in use will be unmounted. The {@link OnObbStateChangeListener} registered 417 * with this call will receive the success or failure of this operation. 418 * <p> 419 * <em>Note:</em> you can only mount OBB files for which the OBB tag on the 420 * file matches a package ID that is owned by the calling program's UID. 421 * That is, shared UID applications can attempt to mount any other 422 * application's OBB that shares its UID. 423 * 424 * @param filename the path to the OBB file 425 * @param key secret used to encrypt the OBB; may be <code>null</code> if no 426 * encryption was used on the OBB. 427 * @param listener will receive the success or failure of the operation 428 * @return whether the mount call was successfully queued or not 429 */ 430 public boolean mountObb(String filename, String key, OnObbStateChangeListener listener) { 431 if (filename == null) { 432 throw new IllegalArgumentException("filename cannot be null"); 433 } 434 435 if (listener == null) { 436 throw new IllegalArgumentException("listener cannot be null"); 437 } 438 439 try { 440 final int nonce = mObbActionListener.addListener(listener); 441 mMountService.mountObb(filename, key, mObbActionListener, nonce); 442 return true; 443 } catch (RemoteException e) { 444 Log.e(TAG, "Failed to mount OBB", e); 445 } 446 447 return false; 448 } 449 450 /** 451 * Unmount an Opaque Binary Blob (OBB) file asynchronously. If the 452 * <code>force</code> flag is true, it will kill any application needed to 453 * unmount the given OBB (even the calling application). 454 * <p> 455 * The {@link OnObbStateChangeListener} registered with this call will 456 * receive the success or failure of this operation. 457 * <p> 458 * <em>Note:</em> you can only mount OBB files for which the OBB tag on the 459 * file matches a package ID that is owned by the calling program's UID. 460 * That is, shared UID applications can obtain access to any other 461 * application's OBB that shares its UID. 462 * <p> 463 * 464 * @param filename path to the OBB file 465 * @param force whether to kill any programs using this in order to unmount 466 * it 467 * @param listener will receive the success or failure of the operation 468 * @return whether the unmount call was successfully queued or not 469 */ 470 public boolean unmountObb(String filename, boolean force, OnObbStateChangeListener listener) { 471 if (filename == null) { 472 throw new IllegalArgumentException("filename cannot be null"); 473 } 474 475 if (listener == null) { 476 throw new IllegalArgumentException("listener cannot be null"); 477 } 478 479 try { 480 final int nonce = mObbActionListener.addListener(listener); 481 mMountService.unmountObb(filename, force, mObbActionListener, nonce); 482 return true; 483 } catch (RemoteException e) { 484 Log.e(TAG, "Failed to mount OBB", e); 485 } 486 487 return false; 488 } 489 490 /** 491 * Check whether an Opaque Binary Blob (OBB) is mounted or not. 492 * 493 * @param filename path to OBB image 494 * @return true if OBB is mounted; false if not mounted or on error 495 */ 496 public boolean isObbMounted(String filename) { 497 if (filename == null) { 498 throw new IllegalArgumentException("filename cannot be null"); 499 } 500 501 try { 502 return mMountService.isObbMounted(filename); 503 } catch (RemoteException e) { 504 Log.e(TAG, "Failed to check if OBB is mounted", e); 505 } 506 507 return false; 508 } 509 510 /** 511 * Check the mounted path of an Opaque Binary Blob (OBB) file. This will 512 * give you the path to where you can obtain access to the internals of the 513 * OBB. 514 * 515 * @param filename path to OBB image 516 * @return absolute path to mounted OBB image data or <code>null</code> if 517 * not mounted or exception encountered trying to read status 518 */ 519 public String getMountedObbPath(String filename) { 520 if (filename == null) { 521 throw new IllegalArgumentException("filename cannot be null"); 522 } 523 524 try { 525 return mMountService.getMountedObbPath(filename); 526 } catch (RemoteException e) { 527 Log.e(TAG, "Failed to find mounted path for OBB", e); 528 } 529 530 return null; 531 } 532 533 /** 534 * Gets the state of a volume via its mountpoint. 535 * @hide 536 */ 537 public String getVolumeState(String mountPoint) { 538 if (mMountService == null) return Environment.MEDIA_REMOVED; 539 try { 540 return mMountService.getVolumeState(mountPoint); 541 } catch (RemoteException e) { 542 Log.e(TAG, "Failed to get volume state", e); 543 return null; 544 } 545 } 546 547 /** 548 * Returns list of all mountable volumes. 549 * @hide 550 */ 551 public StorageVolume[] getVolumeList() { 552 if (mMountService == null) return new StorageVolume[0]; 553 try { 554 Parcelable[] list = mMountService.getVolumeList(); 555 if (list == null) return new StorageVolume[0]; 556 int length = list.length; 557 StorageVolume[] result = new StorageVolume[length]; 558 for (int i = 0; i < length; i++) { 559 result[i] = (StorageVolume)list[i]; 560 } 561 return result; 562 } catch (RemoteException e) { 563 Log.e(TAG, "Failed to get volume list", e); 564 return null; 565 } 566 } 567 568 /** 569 * Returns list of paths for all mountable volumes. 570 * @hide 571 */ 572 public String[] getVolumePaths() { 573 StorageVolume[] volumes = getVolumeList(); 574 if (volumes == null) return null; 575 int count = volumes.length; 576 String[] paths = new String[count]; 577 for (int i = 0; i < count; i++) { 578 paths[i] = volumes[i].getPath(); 579 } 580 return paths; 581 } 582 } 583