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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 android.bluetooth;
18 
19 import android.annotation.RequiresNoPermission;
20 import android.annotation.RequiresPermission;
21 import android.annotation.SuppressLint;
22 import android.bluetooth.annotations.RequiresBluetoothConnectPermission;
23 import android.compat.annotation.UnsupportedAppUsage;
24 import android.net.LocalSocket;
25 import android.os.Build;
26 import android.os.ParcelFileDescriptor;
27 import android.os.ParcelUuid;
28 import android.os.RemoteException;
29 import android.util.Log;
30 
31 import java.io.Closeable;
32 import java.io.FileDescriptor;
33 import java.io.IOException;
34 import java.io.InputStream;
35 import java.io.OutputStream;
36 import java.nio.ByteBuffer;
37 import java.nio.ByteOrder;
38 import java.util.Arrays;
39 import java.util.Locale;
40 import java.util.UUID;
41 
42 /**
43  * A connected or connecting Bluetooth socket.
44  *
45  * <p>The interface for Bluetooth Sockets is similar to that of TCP sockets:
46  * {@link java.net.Socket} and {@link java.net.ServerSocket}. On the server
47  * side, use a {@link BluetoothServerSocket} to create a listening server
48  * socket. When a connection is accepted by the {@link BluetoothServerSocket},
49  * it will return a new {@link BluetoothSocket} to manage the connection.
50  * On the client side, use a single {@link BluetoothSocket} to both initiate
51  * an outgoing connection and to manage the connection.
52  *
53  * <p>The most common type of Bluetooth socket is RFCOMM, which is the type
54  * supported by the Android APIs. RFCOMM is a connection-oriented, streaming
55  * transport over Bluetooth. It is also known as the Serial Port Profile (SPP).
56  *
57  * <p>To create a {@link BluetoothSocket} for connecting to a known device, use
58  * {@link BluetoothDevice#createRfcommSocketToServiceRecord
59  * BluetoothDevice.createRfcommSocketToServiceRecord()}.
60  * Then call {@link #connect()} to attempt a connection to the remote device.
61  * This call will block until a connection is established or the connection
62  * fails.
63  *
64  * <p>To create a {@link BluetoothSocket} as a server (or "host"), see the
65  * {@link BluetoothServerSocket} documentation.
66  *
67  * <p>Once the socket is connected, whether initiated as a client or accepted
68  * as a server, open the IO streams by calling {@link #getInputStream} and
69  * {@link #getOutputStream} in order to retrieve {@link java.io.InputStream}
70  * and {@link java.io.OutputStream} objects, respectively, which are
71  * automatically connected to the socket.
72  *
73  * <p>{@link BluetoothSocket} is thread
74  * safe. In particular, {@link #close} will always immediately abort ongoing
75  * operations and close the socket.
76  *
77  * <div class="special reference">
78  * <h3>Developer Guides</h3>
79  * <p>For more information about using Bluetooth, read the
80  * <a href="{@docRoot}guide/topics/connectivity/bluetooth.html">Bluetooth</a> developer guide.</p>
81  * </div>
82  *
83  * {@see BluetoothServerSocket}
84  * {@see java.io.InputStream}
85  * {@see java.io.OutputStream}
86  */
87 public final class BluetoothSocket implements Closeable {
88     private static final String TAG = "BluetoothSocket";
89     private static final boolean DBG = Log.isLoggable(TAG, Log.DEBUG);
90     private static final boolean VDBG = Log.isLoggable(TAG, Log.VERBOSE);
91 
92     /** @hide */
93     public static final int MAX_RFCOMM_CHANNEL = 30;
94     /*package*/ static final int MAX_L2CAP_PACKAGE_SIZE = 0xFFFF;
95 
96     /** RFCOMM socket */
97     public static final int TYPE_RFCOMM = 1;
98 
99     /** SCO socket */
100     public static final int TYPE_SCO = 2;
101 
102     /** L2CAP socket */
103     public static final int TYPE_L2CAP = 3;
104 
105     /** L2CAP socket on BR/EDR transport
106      * @hide
107      */
108     public static final int TYPE_L2CAP_BREDR = TYPE_L2CAP;
109 
110     /** L2CAP socket on LE transport
111      * @hide
112      */
113     public static final int TYPE_L2CAP_LE = 4;
114 
115     /*package*/ static final int EBADFD = 77;
116     @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
117     /*package*/ static final int EADDRINUSE = 98;
118 
119     /*package*/ static final int SEC_FLAG_ENCRYPT = 1;
120     /*package*/ static final int SEC_FLAG_AUTH = 1 << 1;
121     /*package*/ static final int BTSOCK_FLAG_NO_SDP = 1 << 2;
122     /*package*/ static final int SEC_FLAG_AUTH_MITM = 1 << 3;
123     /*package*/ static final int SEC_FLAG_AUTH_16_DIGIT = 1 << 4;
124 
125     private final int mType;  /* one of TYPE_RFCOMM etc */
126     private BluetoothDevice mDevice;    /* remote device */
127     private String mAddress;    /* remote address */
128     private final boolean mAuth;
129     private final boolean mEncrypt;
130     private final BluetoothInputStream mInputStream;
131     private final BluetoothOutputStream mOutputStream;
132     private final ParcelUuid mUuid;
133     /** when true no SPP SDP record will be created */
134     private boolean mExcludeSdp = false;
135     /** when true Person-in-the-middle protection will be enabled */
136     private boolean mAuthMitm = false;
137     /** Minimum 16 digit pin for sec mode 2 connections */
138     private boolean mMin16DigitPin = false;
139     @UnsupportedAppUsage(publicAlternatives = "Use {@link BluetoothSocket} public API instead.")
140     private ParcelFileDescriptor mPfd;
141     @UnsupportedAppUsage
142     private LocalSocket mSocket;
143     private InputStream mSocketIS;
144     private OutputStream mSocketOS;
145     @UnsupportedAppUsage
146     private int mPort;  /* RFCOMM channel or L2CAP psm */
147     private int mFd;
148     private String mServiceName;
149     private static final int PROXY_CONNECTION_TIMEOUT = 5000;
150 
151     private static final int SOCK_SIGNAL_SIZE = 20;
152 
153     private ByteBuffer mL2capBuffer = null;
154     private int mMaxTxPacketSize = 0; // The l2cap maximum packet size supported by the peer.
155     private int mMaxRxPacketSize = 0; // The l2cap maximum packet size that can be received.
156 
157     private enum SocketState {
158         INIT,
159         CONNECTED,
160         LISTENING,
161         CLOSED,
162     }
163 
164     /** prevents all native calls after destroyNative() */
165     private volatile SocketState mSocketState;
166 
167     /** protects mSocketState */
168     //private final ReentrantReadWriteLock mLock;
169 
170     /**
171      * Construct a BluetoothSocket.
172      *
173      * @param type type of socket
174      * @param fd fd to use for connected socket, or -1 for a new socket
175      * @param auth require the remote device to be authenticated
176      * @param encrypt require the connection to be encrypted
177      * @param device remote device that this socket can connect to
178      * @param port remote port
179      * @param uuid SDP uuid
180      * @throws IOException On error, for example Bluetooth not available, or insufficient
181      * privileges
182      */
BluetoothSocket(int type, int fd, boolean auth, boolean encrypt, BluetoothDevice device, int port, ParcelUuid uuid)183     /*package*/ BluetoothSocket(int type, int fd, boolean auth, boolean encrypt,
184             BluetoothDevice device, int port, ParcelUuid uuid) throws IOException {
185         this(type, fd, auth, encrypt, device, port, uuid, false, false);
186     }
187 
188     /**
189      * Construct a BluetoothSocket.
190      *
191      * @param type type of socket
192      * @param fd fd to use for connected socket, or -1 for a new socket
193      * @param auth require the remote device to be authenticated
194      * @param encrypt require the connection to be encrypted
195      * @param device remote device that this socket can connect to
196      * @param port remote port
197      * @param uuid SDP uuid
198      * @param mitm enforce person-in-the-middle protection.
199      * @param min16DigitPin enforce a minimum length of 16 digits for a sec mode 2 connection
200      * @throws IOException On error, for example Bluetooth not available, or insufficient
201      * privileges
202      */
BluetoothSocket(int type, int fd, boolean auth, boolean encrypt, BluetoothDevice device, int port, ParcelUuid uuid, boolean mitm, boolean min16DigitPin)203     /*package*/ BluetoothSocket(int type, int fd, boolean auth, boolean encrypt,
204             BluetoothDevice device, int port, ParcelUuid uuid, boolean mitm, boolean min16DigitPin)
205             throws IOException {
206         if (VDBG) Log.d(TAG, "Creating new BluetoothSocket of type: " + type);
207         if (type == BluetoothSocket.TYPE_RFCOMM && uuid == null && fd == -1
208                 && port != BluetoothAdapter.SOCKET_CHANNEL_AUTO_STATIC_NO_SDP) {
209             if (port < 1 || port > MAX_RFCOMM_CHANNEL) {
210                 throw new IOException("Invalid RFCOMM channel: " + port);
211             }
212         }
213         if (uuid != null) {
214             mUuid = uuid;
215         } else {
216             mUuid = new ParcelUuid(new UUID(0, 0));
217         }
218         mType = type;
219         mAuth = auth;
220         mAuthMitm = mitm;
221         mMin16DigitPin = min16DigitPin;
222         mEncrypt = encrypt;
223         mDevice = device;
224         mPort = port;
225         mFd = fd;
226 
227         mSocketState = SocketState.INIT;
228 
229         if (device == null) {
230             // Server socket
231             mAddress = BluetoothAdapter.getDefaultAdapter().getAddress();
232         } else {
233             // Remote socket
234             mAddress = device.getAddress();
235         }
236         mInputStream = new BluetoothInputStream(this);
237         mOutputStream = new BluetoothOutputStream(this);
238     }
239 
BluetoothSocket(BluetoothSocket s)240     private BluetoothSocket(BluetoothSocket s) {
241         if (VDBG) Log.d(TAG, "Creating new Private BluetoothSocket of type: " + s.mType);
242         mUuid = s.mUuid;
243         mType = s.mType;
244         mAuth = s.mAuth;
245         mEncrypt = s.mEncrypt;
246         mPort = s.mPort;
247         mInputStream = new BluetoothInputStream(this);
248         mOutputStream = new BluetoothOutputStream(this);
249         mMaxRxPacketSize = s.mMaxRxPacketSize;
250         mMaxTxPacketSize = s.mMaxTxPacketSize;
251 
252         mServiceName = s.mServiceName;
253         mExcludeSdp = s.mExcludeSdp;
254         mAuthMitm = s.mAuthMitm;
255         mMin16DigitPin = s.mMin16DigitPin;
256     }
257 
acceptSocket(String remoteAddr)258     private BluetoothSocket acceptSocket(String remoteAddr) throws IOException {
259         BluetoothSocket as = new BluetoothSocket(this);
260         as.mSocketState = SocketState.CONNECTED;
261         FileDescriptor[] fds = mSocket.getAncillaryFileDescriptors();
262         if (DBG) Log.d(TAG, "socket fd passed by stack fds: " + Arrays.toString(fds));
263         if (fds == null || fds.length != 1) {
264             Log.e(TAG, "socket fd passed from stack failed, fds: " + Arrays.toString(fds));
265             as.close();
266             throw new IOException("bt socket acept failed");
267         }
268 
269         as.mPfd = new ParcelFileDescriptor(fds[0]);
270         as.mSocket = LocalSocket.createConnectedLocalSocket(fds[0]);
271         as.mSocketIS = as.mSocket.getInputStream();
272         as.mSocketOS = as.mSocket.getOutputStream();
273         as.mAddress = remoteAddr;
274         as.mDevice = BluetoothAdapter.getDefaultAdapter().getRemoteDevice(remoteAddr);
275         return as;
276     }
277 
278     /**
279      * Construct a BluetoothSocket from address. Used by native code.
280      *
281      * @param type type of socket
282      * @param fd fd to use for connected socket, or -1 for a new socket
283      * @param auth require the remote device to be authenticated
284      * @param encrypt require the connection to be encrypted
285      * @param address remote device that this socket can connect to
286      * @param port remote port
287      * @throws IOException On error, for example Bluetooth not available, or insufficient
288      * privileges
289      */
BluetoothSocket(int type, int fd, boolean auth, boolean encrypt, String address, int port)290     private BluetoothSocket(int type, int fd, boolean auth, boolean encrypt, String address,
291             int port) throws IOException {
292         this(type, fd, auth, encrypt, new BluetoothDevice(address), port, null, false, false);
293     }
294 
295     /** @hide */
296     @Override
finalize()297     protected void finalize() throws Throwable {
298         try {
299             close();
300         } finally {
301             super.finalize();
302         }
303     }
304 
getSecurityFlags()305     private int getSecurityFlags() {
306         int flags = 0;
307         if (mAuth) {
308             flags |= SEC_FLAG_AUTH;
309         }
310         if (mEncrypt) {
311             flags |= SEC_FLAG_ENCRYPT;
312         }
313         if (mExcludeSdp) {
314             flags |= BTSOCK_FLAG_NO_SDP;
315         }
316         if (mAuthMitm) {
317             flags |= SEC_FLAG_AUTH_MITM;
318         }
319         if (mMin16DigitPin) {
320             flags |= SEC_FLAG_AUTH_16_DIGIT;
321         }
322         return flags;
323     }
324 
325     /**
326      * Get the remote device this socket is connecting, or connected, to.
327      *
328      * @return remote device
329      */
330     @RequiresNoPermission
getRemoteDevice()331     public BluetoothDevice getRemoteDevice() {
332         return mDevice;
333     }
334 
335     /**
336      * Get the input stream associated with this socket.
337      * <p>The input stream will be returned even if the socket is not yet
338      * connected, but operations on that stream will throw IOException until
339      * the associated socket is connected.
340      *
341      * @return InputStream
342      */
343     @RequiresNoPermission
getInputStream()344     public InputStream getInputStream() throws IOException {
345         return mInputStream;
346     }
347 
348     /**
349      * Get the output stream associated with this socket.
350      * <p>The output stream will be returned even if the socket is not yet
351      * connected, but operations on that stream will throw IOException until
352      * the associated socket is connected.
353      *
354      * @return OutputStream
355      */
356     @RequiresNoPermission
getOutputStream()357     public OutputStream getOutputStream() throws IOException {
358         return mOutputStream;
359     }
360 
361     /**
362      * Get the connection status of this socket, ie, whether there is an active connection with
363      * remote device.
364      *
365      * @return true if connected false if not connected
366      */
367     @RequiresNoPermission
isConnected()368     public boolean isConnected() {
369         return mSocketState == SocketState.CONNECTED;
370     }
371 
setServiceName(String name)372     /*package*/ void setServiceName(String name) {
373         mServiceName = name;
374     }
375 
376     /**
377      * Attempt to connect to a remote device.
378      * <p>This method will block until a connection is made or the connection
379      * fails. If this method returns without an exception then this socket
380      * is now connected.
381      * <p>Creating new connections to
382      * remote Bluetooth devices should not be attempted while device discovery
383      * is in progress. Device discovery is a heavyweight procedure on the
384      * Bluetooth adapter and will significantly slow a device connection.
385      * Use {@link BluetoothAdapter#cancelDiscovery()} to cancel an ongoing
386      * discovery. Discovery is not managed by the Activity,
387      * but is run as a system service, so an application should always call
388      * {@link BluetoothAdapter#cancelDiscovery()} even if it
389      * did not directly request a discovery, just to be sure.
390      * <p>{@link #close} can be used to abort this call from another thread.
391      *
392      * @throws IOException on error, for example connection failure
393      */
394     @RequiresBluetoothConnectPermission
395     @RequiresPermission(android.Manifest.permission.BLUETOOTH_CONNECT)
connect()396     public void connect() throws IOException {
397         if (mDevice == null) throw new IOException("Connect is called on null device");
398 
399         try {
400             if (mSocketState == SocketState.CLOSED) throw new IOException("socket closed");
401             IBluetooth bluetoothProxy =
402                     BluetoothAdapter.getDefaultAdapter().getBluetoothService();
403             if (bluetoothProxy == null) throw new IOException("Bluetooth is off");
404             mPfd = bluetoothProxy.getSocketManager().connectSocket(mDevice, mType,
405                     mUuid, mPort, getSecurityFlags());
406             synchronized (this) {
407                 if (DBG) Log.d(TAG, "connect(), SocketState: " + mSocketState + ", mPfd: " + mPfd);
408                 if (mSocketState == SocketState.CLOSED) throw new IOException("socket closed");
409                 if (mPfd == null) throw new IOException("bt socket connect failed");
410                 FileDescriptor fd = mPfd.getFileDescriptor();
411                 mSocket = LocalSocket.createConnectedLocalSocket(fd);
412                 mSocketIS = mSocket.getInputStream();
413                 mSocketOS = mSocket.getOutputStream();
414             }
415             int channel = readInt(mSocketIS);
416             if (channel <= 0) {
417                 throw new IOException("bt socket connect failed");
418             }
419             mPort = channel;
420             waitSocketSignal(mSocketIS);
421             synchronized (this) {
422                 if (mSocketState == SocketState.CLOSED) {
423                     throw new IOException("bt socket closed");
424                 }
425                 mSocketState = SocketState.CONNECTED;
426             }
427         } catch (RemoteException e) {
428             Log.e(TAG, Log.getStackTraceString(new Throwable()));
429             throw new IOException("unable to send RPC: " + e.getMessage());
430         }
431     }
432 
433     /**
434      * Currently returns unix errno instead of throwing IOException,
435      * so that BluetoothAdapter can check the error code for EADDRINUSE
436      */
437     @RequiresPermission(android.Manifest.permission.BLUETOOTH_CONNECT)
bindListen()438     /*package*/ int bindListen() {
439         int ret;
440         if (mSocketState == SocketState.CLOSED) return EBADFD;
441         IBluetooth bluetoothProxy = BluetoothAdapter.getDefaultAdapter().getBluetoothService();
442         if (bluetoothProxy == null) {
443             Log.e(TAG, "bindListen fail, reason: bluetooth is off");
444             return -1;
445         }
446         try {
447             if (DBG) Log.d(TAG, "bindListen(): mPort=" + mPort + ", mType=" + mType);
448             mPfd = bluetoothProxy.getSocketManager().createSocketChannel(mType, mServiceName,
449                     mUuid, mPort, getSecurityFlags());
450         } catch (RemoteException e) {
451             Log.e(TAG, Log.getStackTraceString(new Throwable()));
452             return -1;
453         }
454 
455         // read out port number
456         try {
457             synchronized (this) {
458                 if (DBG) {
459                     Log.d(TAG, "bindListen(), SocketState: " + mSocketState + ", mPfd: " + mPfd);
460                 }
461                 if (mSocketState != SocketState.INIT) return EBADFD;
462                 if (mPfd == null) return -1;
463                 FileDescriptor fd = mPfd.getFileDescriptor();
464                 if (fd == null) {
465                     Log.e(TAG, "bindListen(), null file descriptor");
466                     return -1;
467                 }
468 
469                 if (DBG) Log.d(TAG, "bindListen(), Create LocalSocket");
470                 mSocket = LocalSocket.createConnectedLocalSocket(fd);
471                 if (DBG) Log.d(TAG, "bindListen(), new LocalSocket.getInputStream()");
472                 mSocketIS = mSocket.getInputStream();
473                 mSocketOS = mSocket.getOutputStream();
474             }
475             if (DBG) Log.d(TAG, "bindListen(), readInt mSocketIS: " + mSocketIS);
476             int channel = readInt(mSocketIS);
477             synchronized (this) {
478                 if (mSocketState == SocketState.INIT) {
479                     mSocketState = SocketState.LISTENING;
480                 }
481             }
482             if (DBG) Log.d(TAG, "bindListen(): channel=" + channel + ", mPort=" + mPort);
483             if (mPort <= -1) {
484                 mPort = channel;
485             } // else ASSERT(mPort == channel)
486             ret = 0;
487         } catch (IOException e) {
488             if (mPfd != null) {
489                 try {
490                     mPfd.close();
491                 } catch (IOException e1) {
492                     Log.e(TAG, "bindListen, close mPfd: " + e1);
493                 }
494                 mPfd = null;
495             }
496             Log.e(TAG, "bindListen, fail to get port number, exception: " + e);
497             return -1;
498         }
499         return ret;
500     }
501 
accept(int timeout)502     /*package*/ BluetoothSocket accept(int timeout) throws IOException {
503         BluetoothSocket acceptedSocket;
504         if (mSocketState != SocketState.LISTENING) {
505             throw new IOException("bt socket is not in listen state");
506         }
507         if (timeout > 0) {
508             Log.d(TAG, "accept() set timeout (ms):" + timeout);
509             mSocket.setSoTimeout(timeout);
510         }
511         String RemoteAddr = waitSocketSignal(mSocketIS);
512         if (timeout > 0) {
513             mSocket.setSoTimeout(0);
514         }
515         synchronized (this) {
516             if (mSocketState != SocketState.LISTENING) {
517                 throw new IOException("bt socket is not in listen state");
518             }
519             acceptedSocket = acceptSocket(RemoteAddr);
520             //quick drop the reference of the file handle
521         }
522         return acceptedSocket;
523     }
524 
available()525     /*package*/ int available() throws IOException {
526         if (VDBG) Log.d(TAG, "available: " + mSocketIS);
527         return mSocketIS.available();
528     }
529 
read(byte[] b, int offset, int length)530     /*package*/ int read(byte[] b, int offset, int length) throws IOException {
531         int ret = 0;
532         if (VDBG) Log.d(TAG, "read in:  " + mSocketIS + " len: " + length);
533         if ((mType == TYPE_L2CAP) || (mType == TYPE_L2CAP_LE)) {
534             int bytesToRead = length;
535             if (VDBG) {
536                 Log.v(TAG, "l2cap: read(): offset: " + offset + " length:" + length
537                         + "mL2capBuffer= " + mL2capBuffer);
538             }
539             if (mL2capBuffer == null) {
540                 createL2capRxBuffer();
541             }
542             if (mL2capBuffer.remaining() == 0) {
543                 if (VDBG) Log.v(TAG, "l2cap buffer empty, refilling...");
544                 if (fillL2capRxBuffer() == -1) {
545                     return -1;
546                 }
547             }
548             if (bytesToRead > mL2capBuffer.remaining()) {
549                 bytesToRead = mL2capBuffer.remaining();
550             }
551             if (VDBG) {
552                 Log.v(TAG, "get(): offset: " + offset
553                         + " bytesToRead: " + bytesToRead);
554             }
555             mL2capBuffer.get(b, offset, bytesToRead);
556             ret = bytesToRead;
557         } else {
558             if (VDBG) Log.v(TAG, "default: read(): offset: " + offset + " length:" + length);
559             ret = mSocketIS.read(b, offset, length);
560         }
561         if (ret < 0) {
562             throw new IOException("bt socket closed, read return: " + ret);
563         }
564         if (VDBG) Log.d(TAG, "read out:  " + mSocketIS + " ret: " + ret);
565         return ret;
566     }
567 
write(byte[] b, int offset, int length)568     /*package*/ int write(byte[] b, int offset, int length) throws IOException {
569 
570         //TODO: Since bindings can exist between the SDU size and the
571         //      protocol, we might need to throw an exception instead of just
572         //      splitting the write into multiple smaller writes.
573         //      Rfcomm uses dynamic allocation, and should not have any bindings
574         //      to the actual message length.
575         if (VDBG) Log.d(TAG, "write: " + mSocketOS + " length: " + length);
576         if ((mType == TYPE_L2CAP) || (mType == TYPE_L2CAP_LE)) {
577             if (length <= mMaxTxPacketSize) {
578                 mSocketOS.write(b, offset, length);
579             } else {
580                 if (DBG) {
581                     Log.w(TAG, "WARNING: Write buffer larger than L2CAP packet size!\n"
582                             + "Packet will be divided into SDU packets of size "
583                             + mMaxTxPacketSize);
584                 }
585                 int tmpOffset = offset;
586                 int bytesToWrite = length;
587                 while (bytesToWrite > 0) {
588                     int tmpLength = (bytesToWrite > mMaxTxPacketSize)
589                             ? mMaxTxPacketSize
590                             : bytesToWrite;
591                     mSocketOS.write(b, tmpOffset, tmpLength);
592                     tmpOffset += tmpLength;
593                     bytesToWrite -= tmpLength;
594                 }
595             }
596         } else {
597             mSocketOS.write(b, offset, length);
598         }
599         // There is no good way to confirm since the entire process is asynchronous anyway
600         if (VDBG) Log.d(TAG, "write out: " + mSocketOS + " length: " + length);
601         return length;
602     }
603 
604     @Override
close()605     public void close() throws IOException {
606         Log.d(TAG, "close() this: " + this + ", channel: " + mPort + ", mSocketIS: " + mSocketIS
607                 + ", mSocketOS: " + mSocketOS + "mSocket: " + mSocket + ", mSocketState: "
608                 + mSocketState);
609         if (mSocketState == SocketState.CLOSED) {
610             return;
611         } else {
612             synchronized (this) {
613                 if (mSocketState == SocketState.CLOSED) {
614                     return;
615                 }
616                 mSocketState = SocketState.CLOSED;
617                 if (mSocket != null) {
618                     if (DBG) Log.d(TAG, "Closing mSocket: " + mSocket);
619                     mSocket.shutdownInput();
620                     mSocket.shutdownOutput();
621                     mSocket.close();
622                     mSocket = null;
623                 }
624                 if (mPfd != null) {
625                     mPfd.close();
626                     mPfd = null;
627                 }
628             }
629         }
630     }
631 
removeChannel()632     /*package */ void removeChannel() {
633     }
634 
getPort()635     /*package */ int getPort() {
636         return mPort;
637     }
638 
639     /**
640      * Get the maximum supported Transmit packet size for the underlying transport.
641      * Use this to optimize the writes done to the output socket, to avoid sending
642      * half full packets.
643      *
644      * @return the maximum supported Transmit packet size for the underlying transport.
645      */
646     @RequiresNoPermission
getMaxTransmitPacketSize()647     public int getMaxTransmitPacketSize() {
648         return mMaxTxPacketSize;
649     }
650 
651     /**
652      * Get the maximum supported Receive packet size for the underlying transport.
653      * Use this to optimize the reads done on the input stream, as any call to read
654      * will return a maximum of this amount of bytes - or for some transports a
655      * multiple of this value.
656      *
657      * @return the maximum supported Receive packet size for the underlying transport.
658      */
659     @RequiresNoPermission
getMaxReceivePacketSize()660     public int getMaxReceivePacketSize() {
661         return mMaxRxPacketSize;
662     }
663 
664     /**
665      * Get the type of the underlying connection.
666      *
667      * @return one of {@link #TYPE_RFCOMM}, {@link #TYPE_SCO} or {@link #TYPE_L2CAP}
668      */
669     @RequiresNoPermission
getConnectionType()670     public int getConnectionType() {
671         if (mType == TYPE_L2CAP_LE) {
672             // Treat the LE CoC to be the same type as L2CAP.
673             return TYPE_L2CAP;
674         }
675         return mType;
676     }
677 
678     /**
679      * Change if a SDP entry should be automatically created.
680      * Must be called before calling .bind, for the call to have any effect.
681      *
682      * @param excludeSdp <li>TRUE - do not auto generate SDP record. <li>FALSE - default - auto
683      * generate SPP SDP record.
684      * @hide
685      */
686     @RequiresNoPermission
setExcludeSdp(boolean excludeSdp)687     public void setExcludeSdp(boolean excludeSdp) {
688         mExcludeSdp = excludeSdp;
689     }
690 
691     /**
692      * Set the LE Transmit Data Length to be the maximum that the BT Controller is capable of. This
693      * parameter is used by the BT Controller to set the maximum transmission packet size on this
694      * connection. This function is currently used for testing only.
695      * @hide
696      */
697     @RequiresBluetoothConnectPermission
698     @RequiresPermission(android.Manifest.permission.BLUETOOTH_CONNECT)
requestMaximumTxDataLength()699     public void requestMaximumTxDataLength() throws IOException {
700         if (mDevice == null) {
701             throw new IOException("requestMaximumTxDataLength is called on null device");
702         }
703 
704         try {
705             if (mSocketState == SocketState.CLOSED) {
706                 throw new IOException("socket closed");
707             }
708             IBluetooth bluetoothProxy =
709                     BluetoothAdapter.getDefaultAdapter().getBluetoothService();
710             if (bluetoothProxy == null) {
711                 throw new IOException("Bluetooth is off");
712             }
713 
714             if (DBG) Log.d(TAG, "requestMaximumTxDataLength");
715             bluetoothProxy.getSocketManager().requestMaximumTxDataLength(mDevice);
716         } catch (RemoteException e) {
717             Log.e(TAG, Log.getStackTraceString(new Throwable()));
718             throw new IOException("unable to send RPC: " + e.getMessage());
719         }
720     }
721 
convertAddr(final byte[] addr)722     private String convertAddr(final byte[] addr) {
723         return String.format(Locale.US, "%02X:%02X:%02X:%02X:%02X:%02X",
724                 addr[0], addr[1], addr[2], addr[3], addr[4], addr[5]);
725     }
726 
waitSocketSignal(InputStream is)727     private String waitSocketSignal(InputStream is) throws IOException {
728         byte[] sig = new byte[SOCK_SIGNAL_SIZE];
729         int ret = readAll(is, sig);
730         if (VDBG) {
731             Log.d(TAG, "waitSocketSignal read " + SOCK_SIGNAL_SIZE + " bytes signal ret: " + ret);
732         }
733         ByteBuffer bb = ByteBuffer.wrap(sig);
734         /* the struct in native is decorated with __attribute__((packed)), hence this is possible */
735         bb.order(ByteOrder.nativeOrder());
736         int size = bb.getShort();
737         if (size != SOCK_SIGNAL_SIZE) {
738             throw new IOException("Connection failure, wrong signal size: " + size);
739         }
740         byte[] addr = new byte[6];
741         bb.get(addr);
742         int channel = bb.getInt();
743         int status = bb.getInt();
744         mMaxTxPacketSize = (bb.getShort() & 0xffff); // Convert to unsigned value
745         mMaxRxPacketSize = (bb.getShort() & 0xffff); // Convert to unsigned value
746         String RemoteAddr = convertAddr(addr);
747         if (VDBG) {
748             Log.d(TAG, "waitSocketSignal: sig size: " + size + ", remote addr: "
749                     + RemoteAddr + ", channel: " + channel + ", status: " + status
750                     + " MaxRxPktSize: " + mMaxRxPacketSize + " MaxTxPktSize: " + mMaxTxPacketSize);
751         }
752         if (status != 0) {
753             throw new IOException("Connection failure, status: " + status);
754         }
755         return RemoteAddr;
756     }
757 
createL2capRxBuffer()758     private void createL2capRxBuffer() {
759         if ((mType == TYPE_L2CAP) || (mType == TYPE_L2CAP_LE)) {
760             // Allocate the buffer to use for reads.
761             if (VDBG) Log.v(TAG, "  Creating mL2capBuffer: mMaxPacketSize: " + mMaxRxPacketSize);
762             mL2capBuffer = ByteBuffer.wrap(new byte[mMaxRxPacketSize]);
763             if (VDBG) Log.v(TAG, "mL2capBuffer.remaining()" + mL2capBuffer.remaining());
764             mL2capBuffer.limit(0); // Ensure we do a real read at the first read-request
765             if (VDBG) {
766                 Log.v(TAG, "mL2capBuffer.remaining() after limit(0):" + mL2capBuffer.remaining());
767             }
768         }
769     }
770 
readAll(InputStream is, byte[] b)771     private int readAll(InputStream is, byte[] b) throws IOException {
772         int left = b.length;
773         while (left > 0) {
774             int ret = is.read(b, b.length - left, left);
775             if (ret <= 0) {
776                 throw new IOException("read failed, socket might closed or timeout, read ret: "
777                         + ret);
778             }
779             left -= ret;
780             if (left != 0) {
781                 Log.w(TAG, "readAll() looping, read partial size: " + (b.length - left)
782                         + ", expect size: " + b.length);
783             }
784         }
785         return b.length;
786     }
787 
readInt(InputStream is)788     private int readInt(InputStream is) throws IOException {
789         byte[] ibytes = new byte[4];
790         int ret = readAll(is, ibytes);
791         if (VDBG) Log.d(TAG, "inputStream.read ret: " + ret);
792         ByteBuffer bb = ByteBuffer.wrap(ibytes);
793         bb.order(ByteOrder.nativeOrder());
794         return bb.getInt();
795     }
796 
fillL2capRxBuffer()797     private int fillL2capRxBuffer() throws IOException {
798         mL2capBuffer.rewind();
799         int ret = mSocketIS.read(mL2capBuffer.array());
800         if (ret == -1) {
801             // reached end of stream - return -1
802             mL2capBuffer.limit(0);
803             return -1;
804         }
805         mL2capBuffer.limit(ret);
806         return ret;
807     }
808 
809 
810 }
811