1 /*
2  * Copyright (C) 2014 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.nfc;
18 
19 import java.util.ArrayList;
20 
21 import android.app.Activity;
22 import android.app.ActivityManager;
23 import android.app.ActivityManagerNative;
24 import android.app.AlertDialog;
25 import android.content.BroadcastReceiver;
26 import android.content.Context;
27 import android.content.DialogInterface;
28 import android.content.ClipData;
29 import android.content.Intent;
30 import android.content.IntentFilter;
31 import android.content.pm.PackageManager;
32 import android.net.Uri;
33 import android.nfc.BeamShareData;
34 import android.nfc.NdefMessage;
35 import android.nfc.NdefRecord;
36 import android.nfc.NfcAdapter;
37 import android.os.Bundle;
38 import android.os.UserHandle;
39 import android.os.RemoteException;
40 import android.util.Log;
41 import android.util.EventLog;
42 import android.webkit.URLUtil;
43 import android.Manifest.permission;
44 
45 import com.android.internal.R;
46 
47 /**
48  * This class is registered by NfcService to handle
49  * ACTION_SHARE intents. It tries to parse data contained
50  * in ACTION_SHARE intents in either a content/file Uri,
51  * which can be sent using NFC handover, or alternatively
52  * it tries to parse texts and URLs to store them in a simple
53  * Text or Uri NdefRecord. The data is then passed on into
54  * NfcService to transmit on NFC tap.
55  *
56  */
57 public class BeamShareActivity extends Activity {
58     static final String TAG ="BeamShareActivity";
59     static final boolean DBG = false;
60 
61     ArrayList<Uri> mUris;
62     NdefMessage mNdefMessage;
63     NfcAdapter mNfcAdapter;
64     Intent mLaunchIntent;
65 
66     @Override
onCreate(Bundle savedInstanceState)67     protected void onCreate(Bundle savedInstanceState) {
68         super.onCreate(savedInstanceState);
69         mUris = new ArrayList<Uri>();
70         mNdefMessage = null;
71         mNfcAdapter = NfcAdapter.getDefaultAdapter(this);
72         mLaunchIntent = getIntent();
73         if (mNfcAdapter == null) {
74             Log.e(TAG, "NFC adapter not present.");
75             finish();
76         } else {
77             if (!mNfcAdapter.isEnabled()) {
78                 showNfcDialogAndExit(com.android.nfc.R.string.beam_requires_nfc_enabled);
79             } else {
80                 parseShareIntentAndFinish(mLaunchIntent);
81             }
82         }
83     }
84 
85     @Override
onDestroy()86     protected void onDestroy() {
87         try {
88             unregisterReceiver(mReceiver);
89         } catch (Exception e) {
90             Log.w(TAG, e.getMessage());
91         }
92         super.onDestroy();
93     }
94 
showNfcDialogAndExit(int msgId)95     private void showNfcDialogAndExit(int msgId) {
96         IntentFilter filter = new IntentFilter(NfcAdapter.ACTION_ADAPTER_STATE_CHANGED);
97         registerReceiverAsUser(mReceiver, UserHandle.ALL, filter, null, null);
98 
99         AlertDialog.Builder dialogBuilder = new AlertDialog.Builder(this,
100                 AlertDialog.THEME_DEVICE_DEFAULT_LIGHT);
101         dialogBuilder.setMessage(msgId);
102         dialogBuilder.setOnCancelListener(new DialogInterface.OnCancelListener() {
103             @Override
104             public void onCancel(DialogInterface dialogInterface) {
105                 finish();
106             }
107         });
108         dialogBuilder.setPositiveButton(R.string.yes,
109                 new DialogInterface.OnClickListener() {
110                     @Override
111                     public void onClick(DialogInterface dialog, int id) {
112                         if (!mNfcAdapter.isEnabled()) {
113                             mNfcAdapter.enable();
114                             // Wait for enable broadcast
115                         } else {
116                             parseShareIntentAndFinish(mLaunchIntent);
117                         }
118                     }
119                 });
120         dialogBuilder.setNegativeButton(R.string.no,
121                 new DialogInterface.OnClickListener() {
122                     @Override
123                     public void onClick(DialogInterface dialogInterface, int i) {
124                         finish();
125                     }
126                 });
127         dialogBuilder.show();
128     }
129 
tryUri(Uri uri)130     void tryUri(Uri uri) {
131         if (uri.getScheme().equalsIgnoreCase("content") ||
132                 uri.getScheme().equalsIgnoreCase("file")) {
133             // Typically larger data, this can be shared using NFC handover
134             mUris.add(uri);
135         } else {
136             // Just put this Uri in an NDEF message
137             mNdefMessage = new NdefMessage(NdefRecord.createUri(uri));
138         }
139     }
140 
tryText(String text)141     void tryText(String text) {
142         if (URLUtil.isValidUrl(text)) {
143             Uri parsedUri = Uri.parse(text);
144             tryUri(parsedUri);
145         } else {
146             mNdefMessage = new NdefMessage(NdefRecord.createTextRecord(null, text));
147         }
148     }
149 
parseShareIntentAndFinish(Intent intent)150     public void parseShareIntentAndFinish(Intent intent) {
151         if (intent == null || intent.getAction() == null ||
152                 (!intent.getAction().equalsIgnoreCase(Intent.ACTION_SEND) &&
153                 !intent.getAction().equalsIgnoreCase(Intent.ACTION_SEND_MULTIPLE))) return;
154 
155         // First, see if the intent contains clip-data, and if so get data from there
156         ClipData clipData = intent.getClipData();
157         if (clipData != null && clipData.getItemCount() > 0) {
158             for (int i = 0; i < clipData.getItemCount(); i++) {
159                 ClipData.Item item = clipData.getItemAt(i);
160                 // First try to get an Uri
161                 Uri uri = item.getUri();
162                 String plainText = null;
163                 try {
164                     plainText = item.coerceToText(this).toString();
165                 } catch (IllegalStateException e) {
166                     if (DBG) Log.d(TAG, e.getMessage());
167                     continue;
168                 }
169                 if (uri != null) {
170                     if (DBG) Log.d(TAG, "Found uri in ClipData.");
171                     tryUri(uri);
172                 } else if (plainText != null) {
173                     if (DBG) Log.d(TAG, "Found text in ClipData.");
174                     tryText(plainText);
175                 } else {
176                     if (DBG) Log.d(TAG, "Did not find any shareable data in ClipData.");
177                 }
178             }
179         } else {
180             if (intent.getAction().equalsIgnoreCase(Intent.ACTION_SEND)) {
181                 final Uri uri = intent.getParcelableExtra(Intent.EXTRA_STREAM);
182                 final CharSequence text = intent.getCharSequenceExtra(Intent.EXTRA_TEXT);
183                 if (uri != null) {
184                     if (DBG) Log.d(TAG, "Found uri in ACTION_SEND intent.");
185                     tryUri(uri);
186                 } else if (text != null) {
187                     if (DBG) Log.d(TAG, "Found EXTRA_TEXT in ACTION_SEND intent.");
188                     tryText(text.toString());
189                 } else {
190                     if (DBG) Log.d(TAG, "Did not find any shareable data in ACTION_SEND intent.");
191                 }
192             } else {
193                 final ArrayList<Uri> uris = intent.getParcelableArrayListExtra(Intent.EXTRA_STREAM);
194                 final ArrayList<CharSequence> texts = intent.getCharSequenceArrayListExtra(
195                         Intent.EXTRA_TEXT);
196 
197                 if (uris != null && uris.size() > 0) {
198                     for (Uri uri : uris) {
199                         if (DBG) Log.d(TAG, "Found uri in ACTION_SEND_MULTIPLE intent.");
200                         tryUri(uri);
201                     }
202                 } else if (texts != null && texts.size() > 0) {
203                     // Try EXTRA_TEXT, but just for the first record
204                     if (DBG) Log.d(TAG, "Found text in ACTION_SEND_MULTIPLE intent.");
205                     tryText(texts.get(0).toString());
206                 } else {
207                     if (DBG) Log.d(TAG, "Did not find any shareable data in " +
208                             "ACTION_SEND_MULTIPLE intent.");
209                 }
210             }
211         }
212 
213         BeamShareData shareData = null;
214         UserHandle myUserHandle = new UserHandle(UserHandle.myUserId());
215         if (mUris.size() > 0) {
216             // Uris have our first preference for sharing
217             Uri[] uriArray = new Uri[mUris.size()];
218             int numValidUris = 0;
219             for (Uri uri : mUris) {
220                 try {
221                     int uid = ActivityManagerNative.getDefault().getLaunchedFromUid(getActivityToken());
222                     if (uri.getScheme().equalsIgnoreCase("file") &&
223                             getApplicationContext().checkPermission(permission.READ_EXTERNAL_STORAGE, -1, uid) !=
224                             PackageManager.PERMISSION_GRANTED) {
225                         Log.e(TAG, "File based Uri doesn't have External Storage Permission.");
226                         EventLog.writeEvent(0x534e4554, "37287958", uid, uri.getPath());
227                         break;
228                     }
229                     grantUriPermission("com.android.nfc", uri, Intent.FLAG_GRANT_READ_URI_PERMISSION);
230                     uriArray[numValidUris++] = uri;
231                     if (DBG) Log.d(TAG, "Found uri: " + uri);
232                 } catch (SecurityException e) {
233                     Log.e(TAG, "Security exception granting uri permission to NFC process.");
234                     break;
235                 } catch (RemoteException e) {
236                     Log.e(TAG, "Remote exception accessing uid of the calling process.");
237                     break;
238                 }
239             }
240             if (numValidUris != 0 && numValidUris == mUris.size()) {
241                 shareData = new BeamShareData(null, uriArray, myUserHandle, 0);
242             } else {
243                 // No uris left
244                 shareData = new BeamShareData(null, null, myUserHandle, 0);
245             }
246         } else if (mNdefMessage != null) {
247             shareData = new BeamShareData(mNdefMessage, null, myUserHandle, 0);
248             if (DBG) Log.d(TAG, "Created NDEF message:" + mNdefMessage.toString());
249         } else {
250             if (DBG) Log.d(TAG, "Could not find any data to parse.");
251             // Activity may have set something to share over NFC, so pass on anyway
252             shareData = new BeamShareData(null, null, myUserHandle, 0);
253         }
254         mNfcAdapter.invokeBeam(shareData);
255         finish();
256     }
257 
258     final BroadcastReceiver mReceiver = new BroadcastReceiver() {
259         @Override
260         public void onReceive(Context context, Intent intent) {
261             String action = intent.getAction();
262             if (NfcAdapter.ACTION_ADAPTER_STATE_CHANGED.equals(intent.getAction())) {
263                 int state = intent.getIntExtra(NfcAdapter.EXTRA_ADAPTER_STATE,
264                         NfcAdapter.STATE_OFF);
265                 if (state == NfcAdapter.STATE_ON) {
266                     parseShareIntentAndFinish(mLaunchIntent);
267                 }
268             }
269         }
270     };
271 }
272