diff options
Diffstat (limited to 'packages/ExternalStorageProvider/src/com/android/externalstorage/ExternalStorageProvider.java')
| -rw-r--r-- | packages/ExternalStorageProvider/src/com/android/externalstorage/ExternalStorageProvider.java | 162 |
1 files changed, 109 insertions, 53 deletions
diff --git a/packages/ExternalStorageProvider/src/com/android/externalstorage/ExternalStorageProvider.java b/packages/ExternalStorageProvider/src/com/android/externalstorage/ExternalStorageProvider.java index 087275e73ee8..53e17e35953d 100644 --- a/packages/ExternalStorageProvider/src/com/android/externalstorage/ExternalStorageProvider.java +++ b/packages/ExternalStorageProvider/src/com/android/externalstorage/ExternalStorageProvider.java @@ -16,6 +16,8 @@ package com.android.externalstorage; +import static java.util.regex.Pattern.CASE_INSENSITIVE; + import android.annotation.NonNull; import android.annotation.Nullable; import android.app.usage.StorageStatsManager; @@ -61,9 +63,22 @@ import java.io.IOException; import java.io.PrintWriter; import java.util.Collections; import java.util.List; +import java.util.Locale; import java.util.Objects; import java.util.UUID; - +import java.util.regex.Pattern; + +/** + * Presents content of the shared (a.k.a. "external") storage. + * <p> + * Starting with Android 11 (R), restricts access to the certain sections of the shared storage: + * {@code Android/data/}, {@code Android/obb/} and {@code Android/sandbox/}, that will be hidden in + * the DocumentsUI by default. + * See <a href="https://developer.android.com/about/versions/11/privacy/storage"> + * Storage updates in Android 11</a>. + * <p> + * Documents ID format: {@code root:path/to/file}. + */ public class ExternalStorageProvider extends FileSystemProvider { private static final String TAG = "ExternalStorage"; @@ -74,7 +89,12 @@ public class ExternalStorageProvider extends FileSystemProvider { private static final Uri BASE_URI = new Uri.Builder().scheme(ContentResolver.SCHEME_CONTENT).authority(AUTHORITY).build(); - // docId format: root:path/to/file + /** + * Regex for detecting {@code /Android/data/}, {@code /Android/obb/} and + * {@code /Android/sandbox/} along with all their subdirectories and content. + */ + private static final Pattern PATTERN_RESTRICTED_ANDROID_SUBTREES = + Pattern.compile("^Android/(?:data|obb|sandbox)(?:/.+)?", CASE_INSENSITIVE); private static final String[] DEFAULT_ROOT_PROJECTION = new String[] { Root.COLUMN_ROOT_ID, Root.COLUMN_FLAGS, Root.COLUMN_ICON, Root.COLUMN_TITLE, @@ -276,70 +296,91 @@ public class ExternalStorageProvider extends FileSystemProvider { return projection != null ? projection : DEFAULT_ROOT_PROJECTION; } + /** + * Mark {@code Android/data/}, {@code Android/obb/} and {@code Android/sandbox/} on the + * integrated shared ("external") storage along with all their content and subdirectories as + * hidden. + */ @Override - public Cursor queryChildDocumentsForManage( - String parentDocId, String[] projection, String sortOrder) - throws FileNotFoundException { - return queryChildDocumentsShowAll(parentDocId, projection, sortOrder); + protected boolean shouldHideDocument(@NonNull String documentId) { + // Don't need to hide anything on USB drives. + if (isOnRemovableUsbStorage(documentId)) { + return false; + } + + final String path = getPathFromDocId(documentId); + return PATTERN_RESTRICTED_ANDROID_SUBTREES.matcher(path).matches(); } /** * Check that the directory is the root of storage or blocked file from tree. + * <p> + * Note, that this is different from hidden documents: blocked documents <b>WILL</b> appear + * the UI, but the user <b>WILL NOT</b> be able to select them. * - * @param docId the docId of the directory to be checked + * @param documentId the docId of the directory to be checked * @return true, should be blocked from tree. Otherwise, false. + * + * @see Document#FLAG_DIR_BLOCKS_OPEN_DOCUMENT_TREE */ @Override - protected boolean shouldBlockFromTree(@NonNull String docId) { - try { - final File dir = getFileForDocId(docId, false /* visible */); + protected boolean shouldBlockDirectoryFromTree(@NonNull String documentId) + throws FileNotFoundException { + final File dir = getFileForDocId(documentId, false); + // The file is null or it is not a directory + if (dir == null || !dir.isDirectory()) { + return false; + } - // the file is null or it is not a directory - if (dir == null || !dir.isDirectory()) { - return false; - } + // Allow all directories on USB, including the root. + if (isOnRemovableUsbStorage(documentId)) { + return false; + } - // Allow all directories on USB, including the root. - try { - RootInfo rootInfo = getRootFromDocId(docId); - if ((rootInfo.flags & Root.FLAG_REMOVABLE_USB) == Root.FLAG_REMOVABLE_USB) { - return false; - } - } catch (FileNotFoundException e) { - Log.e(TAG, "Failed to determine rootInfo for docId"); - } + // Get canonical(!) path. Note that this path will have neither leading nor training "/". + // This the root's path will be just an empty string. + final String path = getPathFromDocId(documentId); - final String path = getPathFromDocId(docId); + // Block the root of the storage + if (path.isEmpty()) { + return true; + } - // Block the root of the storage - if (path.isEmpty()) { - return true; - } + // Block /Download/ and /Android/ folders from the tree. + if (equalIgnoringCase(path, Environment.DIRECTORY_DOWNLOADS) || + equalIgnoringCase(path, Environment.DIRECTORY_ANDROID)) { + return true; + } - // Block Download folder from tree - if (TextUtils.equals(Environment.DIRECTORY_DOWNLOADS.toLowerCase(), - path.toLowerCase())) { - return true; - } + // This shouldn't really make a difference, but just in case - let's block hidden + // directories as well. + if (shouldHideDocument(documentId)) { + return true; + } - if (TextUtils.equals(Environment.DIRECTORY_ANDROID.toLowerCase(), - path.toLowerCase())) { - return true; - } + return false; + } + private boolean isOnRemovableUsbStorage(@NonNull String documentId) { + final RootInfo rootInfo; + try { + rootInfo = getRootFromDocId(documentId); + } catch (FileNotFoundException e) { + Log.e(TAG, "Failed to determine rootInfo for docId\"" + documentId + '"'); return false; - } catch (IOException e) { - throw new IllegalArgumentException( - "Failed to determine if " + docId + " should block from tree " + ": " + e); } + + return (rootInfo.flags & Root.FLAG_REMOVABLE_USB) != 0; } + @NonNull @Override - protected String getDocIdForFile(File file) throws FileNotFoundException { + protected String getDocIdForFile(@NonNull File file) throws FileNotFoundException { return getDocIdForFileMaybeCreate(file, false); } - private String getDocIdForFileMaybeCreate(File file, boolean createNewDir) + @NonNull + private String getDocIdForFileMaybeCreate(@NonNull File file, boolean createNewDir) throws FileNotFoundException { String path = file.getAbsolutePath(); @@ -409,26 +450,30 @@ public class ExternalStorageProvider extends FileSystemProvider { private File getFileForDocId(String docId, boolean visible, boolean mustExist) throws FileNotFoundException { RootInfo root = getRootFromDocId(docId); - return buildFile(root, docId, visible, mustExist); + return buildFile(root, docId, mustExist); } - private Pair<RootInfo, File> resolveDocId(String docId, boolean visible) - throws FileNotFoundException { + private Pair<RootInfo, File> resolveDocId(String docId) throws FileNotFoundException { RootInfo root = getRootFromDocId(docId); - return Pair.create(root, buildFile(root, docId, visible, true)); + return Pair.create(root, buildFile(root, docId, /* mustExist */ true)); } @VisibleForTesting static String getPathFromDocId(String docId) { final int splitIndex = docId.indexOf(':', 1); - final String path = docId.substring(splitIndex + 1); + final String docIdPath = docId.substring(splitIndex + 1); - if (path.isEmpty()) { - return path; + // Canonicalize path and strip the leading "/" + final String path; + try { + path = new File(docIdPath).getCanonicalPath().substring(1); + } catch (IOException e) { + Log.w(TAG, "Could not canonicalize \"" + docIdPath + '"'); + return ""; } - // remove trailing "/" - if (path.charAt(path.length() - 1) == '/') { + // Remove the trailing "/" as well. + if (!path.isEmpty() && path.charAt(path.length() - 1) == '/') { return path.substring(0, path.length() - 1); } else { return path; @@ -450,7 +495,7 @@ public class ExternalStorageProvider extends FileSystemProvider { return root; } - private File buildFile(RootInfo root, String docId, boolean visible, boolean mustExist) + private File buildFile(RootInfo root, String docId, boolean mustExist) throws FileNotFoundException { final int splitIndex = docId.indexOf(':', 1); final String path = docId.substring(splitIndex + 1); @@ -529,7 +574,7 @@ public class ExternalStorageProvider extends FileSystemProvider { @Override public Path findDocumentPath(@Nullable String parentDocId, String childDocId) throws FileNotFoundException { - final Pair<RootInfo, File> resolvedDocId = resolveDocId(childDocId, false); + final Pair<RootInfo, File> resolvedDocId = resolveDocId(childDocId); final RootInfo root = resolvedDocId.first; File child = resolvedDocId.second; @@ -633,6 +678,13 @@ public class ExternalStorageProvider extends FileSystemProvider { } } + /** + * Print the state into the given stream. + * Gets invoked when you run: + * <pre> + * adb shell dumpsys activity provider com.android.externalstorage/.ExternalStorageProvider + * </pre> + */ @Override public void dump(FileDescriptor fd, PrintWriter writer, String[] args) { final IndentingPrintWriter pw = new IndentingPrintWriter(writer, " ", 160); @@ -716,4 +768,8 @@ public class ExternalStorageProvider extends FileSystemProvider { } return bundle; } + + private static boolean equalIgnoringCase(@NonNull String a, @NonNull String b) { + return TextUtils.equals(a.toLowerCase(Locale.ROOT), b.toLowerCase(Locale.ROOT)); + } } |