1 /*
2  * Copyright (C) 2012 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 com.android.providers.downloads;
18 
19 import static android.app.DownloadManager.COLUMN_LOCAL_FILENAME;
20 import static android.app.DownloadManager.COLUMN_LOCAL_URI;
21 import static android.app.DownloadManager.COLUMN_MEDIA_TYPE;
22 import static android.app.DownloadManager.COLUMN_URI;
23 import static android.provider.Downloads.Impl.ALL_DOWNLOADS_CONTENT_URI;
24 import static com.android.providers.downloads.Constants.TAG;
25 
26 import android.app.DownloadManager;
27 import android.content.ActivityNotFoundException;
28 import android.content.ContentUris;
29 import android.content.Context;
30 import android.content.Intent;
31 import android.database.Cursor;
32 import android.net.Uri;
33 import android.os.StrictMode;
34 import android.provider.DocumentsContract;
35 import android.provider.Downloads.Impl.RequestHeaders;
36 import android.util.Log;
37 
38 import java.io.File;
39 
40 public class OpenHelper {
41     /**
42      * Build and start an {@link Intent} to view the download with given ID,
43      * handling subtleties around installing packages.
44      */
startViewIntent(Context context, long id, int intentFlags)45     public static boolean startViewIntent(Context context, long id, int intentFlags) {
46         final Intent intent = OpenHelper.buildViewIntent(context, id);
47         if (intent == null) {
48             Log.w(TAG, "No intent built for " + id);
49             return false;
50         }
51 
52         intent.addFlags(intentFlags);
53         try {
54             StrictMode.disableDeathOnFileUriExposure();
55             context.startActivity(intent);
56             return true;
57         } catch (ActivityNotFoundException e) {
58             Log.w(TAG, "Failed to start " + intent + ": " + e);
59             return false;
60         } finally {
61             StrictMode.enableDeathOnFileUriExposure();
62         }
63     }
64 
65     /**
66      * Build an {@link Intent} to view the download with given ID, handling
67      * subtleties around installing packages.
68      */
buildViewIntent(Context context, long id)69     private static Intent buildViewIntent(Context context, long id) {
70         final DownloadManager downManager = (DownloadManager) context.getSystemService(
71                 Context.DOWNLOAD_SERVICE);
72         downManager.setAccessAllDownloads(true);
73         downManager.setAccessFilename(true);
74 
75         final Cursor cursor = downManager.query(new DownloadManager.Query().setFilterById(id));
76         try {
77             if (!cursor.moveToFirst()) {
78                 return null;
79             }
80 
81             final Uri localUri = getCursorUri(cursor, COLUMN_LOCAL_URI);
82             final File file = getCursorFile(cursor, COLUMN_LOCAL_FILENAME);
83             String mimeType = getCursorString(cursor, COLUMN_MEDIA_TYPE);
84             mimeType = DownloadDrmHelper.getOriginalMimeType(context, file, mimeType);
85 
86             final Uri documentUri = DocumentsContract.buildDocumentUri(
87                     Constants.STORAGE_AUTHORITY, String.valueOf(id));
88 
89             final Intent intent = new Intent(Intent.ACTION_VIEW);
90 
91             if ("application/vnd.android.package-archive".equals(mimeType)) {
92                 // PackageInstaller doesn't like content URIs, so open file
93                 intent.setDataAndType(localUri, mimeType);
94 
95                 // Also splice in details about where it came from
96                 final Uri remoteUri = getCursorUri(cursor, COLUMN_URI);
97                 intent.putExtra(Intent.EXTRA_ORIGINATING_URI, remoteUri);
98                 intent.putExtra(Intent.EXTRA_REFERRER, getRefererUri(context, id));
99                 intent.putExtra(Intent.EXTRA_ORIGINATING_UID, getOriginatingUid(context, id));
100             } else {
101                 intent.setDataAndType(documentUri, mimeType);
102                 intent.setFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION
103                         | Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
104             }
105 
106             return intent;
107         } finally {
108             cursor.close();
109         }
110     }
111 
getRefererUri(Context context, long id)112     private static Uri getRefererUri(Context context, long id) {
113         final Uri headersUri = Uri.withAppendedPath(
114                 ContentUris.withAppendedId(ALL_DOWNLOADS_CONTENT_URI, id),
115                 RequestHeaders.URI_SEGMENT);
116         final Cursor headers = context.getContentResolver()
117                 .query(headersUri, null, null, null, null);
118         try {
119             while (headers.moveToNext()) {
120                 final String header = getCursorString(headers, RequestHeaders.COLUMN_HEADER);
121                 if ("Referer".equalsIgnoreCase(header)) {
122                     return getCursorUri(headers, RequestHeaders.COLUMN_VALUE);
123                 }
124             }
125         } finally {
126             headers.close();
127         }
128         return null;
129     }
130 
getOriginatingUid(Context context, long id)131     private static int getOriginatingUid(Context context, long id) {
132         final Uri uri = ContentUris.withAppendedId(ALL_DOWNLOADS_CONTENT_URI, id);
133         final Cursor cursor = context.getContentResolver().query(uri, new String[]{Constants.UID},
134                 null, null, null);
135         if (cursor != null) {
136             try {
137                 if (cursor.moveToFirst()) {
138                     return cursor.getInt(cursor.getColumnIndexOrThrow(Constants.UID));
139                 }
140             } finally {
141                 cursor.close();
142             }
143         }
144         return -1;
145     }
146 
getCursorString(Cursor cursor, String column)147     private static String getCursorString(Cursor cursor, String column) {
148         return cursor.getString(cursor.getColumnIndexOrThrow(column));
149     }
150 
getCursorUri(Cursor cursor, String column)151     private static Uri getCursorUri(Cursor cursor, String column) {
152         return Uri.parse(getCursorString(cursor, column));
153     }
154 
getCursorFile(Cursor cursor, String column)155     private static File getCursorFile(Cursor cursor, String column) {
156         return new File(cursor.getString(cursor.getColumnIndexOrThrow(column)));
157     }
158 }
159