XmppConnection.java

   1package eu.siacs.conversations.xmpp;
   2
   3import java.io.IOException;
   4import java.io.InputStream;
   5import java.io.OutputStream;
   6import java.math.BigInteger;
   7import java.net.Socket;
   8import java.net.UnknownHostException;
   9import java.security.KeyManagementException;
  10import java.security.NoSuchAlgorithmException;
  11import java.security.SecureRandom;
  12import java.util.ArrayList;
  13import java.util.Arrays;
  14import java.util.HashMap;
  15import java.util.Hashtable;
  16import java.util.LinkedList;
  17import java.util.List;
  18import java.util.Map.Entry;
  19
  20import javax.net.ssl.HostnameVerifier;
  21import javax.net.ssl.SSLContext;
  22import javax.net.ssl.SSLSocket;
  23import javax.net.ssl.SSLSocketFactory;
  24
  25import javax.net.ssl.X509TrustManager;
  26
  27import org.xmlpull.v1.XmlPullParserException;
  28
  29import de.duenndns.ssl.MemorizingTrustManager;
  30
  31import android.content.Context;
  32import android.content.SharedPreferences;
  33import android.os.Bundle;
  34import android.os.PowerManager;
  35import android.os.PowerManager.WakeLock;
  36import android.os.SystemClock;
  37import android.preference.PreferenceManager;
  38import android.util.Log;
  39import android.util.SparseArray;
  40import eu.siacs.conversations.Config;
  41import eu.siacs.conversations.entities.Account;
  42import eu.siacs.conversations.services.XmppConnectionService;
  43import eu.siacs.conversations.utils.CryptoHelper;
  44import eu.siacs.conversations.utils.DNSHelper;
  45import eu.siacs.conversations.utils.zlib.ZLibOutputStream;
  46import eu.siacs.conversations.utils.zlib.ZLibInputStream;
  47import eu.siacs.conversations.xml.Element;
  48import eu.siacs.conversations.xml.Tag;
  49import eu.siacs.conversations.xml.TagWriter;
  50import eu.siacs.conversations.xml.XmlReader;
  51import eu.siacs.conversations.xmpp.jingle.OnJinglePacketReceived;
  52import eu.siacs.conversations.xmpp.jingle.stanzas.JinglePacket;
  53import eu.siacs.conversations.xmpp.stanzas.AbstractStanza;
  54import eu.siacs.conversations.xmpp.stanzas.IqPacket;
  55import eu.siacs.conversations.xmpp.stanzas.MessagePacket;
  56import eu.siacs.conversations.xmpp.stanzas.PresencePacket;
  57import eu.siacs.conversations.xmpp.stanzas.csi.ActivePacket;
  58import eu.siacs.conversations.xmpp.stanzas.csi.InactivePacket;
  59import eu.siacs.conversations.xmpp.stanzas.streammgmt.AckPacket;
  60import eu.siacs.conversations.xmpp.stanzas.streammgmt.EnablePacket;
  61import eu.siacs.conversations.xmpp.stanzas.streammgmt.RequestPacket;
  62import eu.siacs.conversations.xmpp.stanzas.streammgmt.ResumePacket;
  63
  64public class XmppConnection implements Runnable {
  65
  66	protected Account account;
  67
  68	private WakeLock wakeLock;
  69
  70	private SecureRandom mRandom;
  71
  72	private Socket socket;
  73	private XmlReader tagReader;
  74	private TagWriter tagWriter;
  75
  76	private Features features = new Features(this);
  77
  78	private boolean shouldBind = true;
  79	private boolean shouldAuthenticate = true;
  80	private Element streamFeatures;
  81	private HashMap<String, List<String>> disco = new HashMap<String, List<String>>();
  82
  83	private String streamId = null;
  84	private int smVersion = 3;
  85	private SparseArray<String> messageReceipts = new SparseArray<String>();
  86
  87	private boolean usingCompression = false;
  88	private boolean usingEncryption = false;
  89
  90	private int stanzasReceived = 0;
  91	private int stanzasSent = 0;
  92
  93	private long lastPaketReceived = 0;
  94	private long lastPingSent = 0;
  95	private long lastConnect = 0;
  96	private long lastSessionStarted = 0;
  97
  98	private int attempt = 0;
  99
 100	private static final int PACKET_IQ = 0;
 101	private static final int PACKET_MESSAGE = 1;
 102	private static final int PACKET_PRESENCE = 2;
 103
 104	private Hashtable<String, PacketReceived> packetCallbacks = new Hashtable<String, PacketReceived>();
 105	private OnPresencePacketReceived presenceListener = null;
 106	private OnJinglePacketReceived jingleListener = null;
 107	private OnIqPacketReceived unregisteredIqListener = null;
 108	private OnMessagePacketReceived messageListener = null;
 109	private OnStatusChanged statusListener = null;
 110	private OnBindListener bindListener = null;
 111	private OnMessageAcknowledged acknowledgedListener = null;
 112	private MemorizingTrustManager mMemorizingTrustManager;
 113    private final Context applicationContext;
 114
 115	public XmppConnection(Account account, XmppConnectionService service) {
 116		this.mRandom = service.getRNG();
 117		this.mMemorizingTrustManager = service.getMemorizingTrustManager();
 118		this.account = account;
 119		this.wakeLock = service.getPowerManager().newWakeLock(
 120				PowerManager.PARTIAL_WAKE_LOCK, account.getJid());
 121		tagWriter = new TagWriter();
 122        applicationContext = service.getApplicationContext();
 123	}
 124
 125	protected void changeStatus(int nextStatus) {
 126		if (account.getStatus() != nextStatus) {
 127			if ((nextStatus == Account.STATUS_OFFLINE)
 128					&& (account.getStatus() != Account.STATUS_CONNECTING)
 129					&& (account.getStatus() != Account.STATUS_ONLINE)
 130					&& (account.getStatus() != Account.STATUS_DISABLED)) {
 131				return;
 132			}
 133			if (nextStatus == Account.STATUS_ONLINE) {
 134				this.attempt = 0;
 135			}
 136			account.setStatus(nextStatus);
 137			if (statusListener != null) {
 138				statusListener.onStatusChanged(account);
 139			}
 140		}
 141	}
 142
 143	protected void connect() {
 144		Log.d(Config.LOGTAG, account.getJid() + ": connecting");
 145		usingCompression = false;
 146		usingEncryption = false;
 147		lastConnect = SystemClock.elapsedRealtime();
 148		lastPingSent = SystemClock.elapsedRealtime();
 149		this.attempt++;
 150		try {
 151			shouldAuthenticate = shouldBind = !account
 152					.isOptionSet(Account.OPTION_REGISTER);
 153			tagReader = new XmlReader(wakeLock);
 154			tagWriter = new TagWriter();
 155			packetCallbacks.clear();
 156			this.changeStatus(Account.STATUS_CONNECTING);
 157			Bundle namePort = DNSHelper.getSRVRecord(account.getServer());
 158			if ("timeout".equals(namePort.getString("error"))) {
 159				Log.d(Config.LOGTAG, account.getJid() + ": dns timeout");
 160				this.changeStatus(Account.STATUS_OFFLINE);
 161				return;
 162			}
 163			String srvRecordServer = namePort.getString("name");
 164			String srvIpServer = namePort.getString("ipv4");
 165			int srvRecordPort = namePort.getInt("port");
 166			if (srvRecordServer != null) {
 167				if (srvIpServer != null) {
 168					Log.d(Config.LOGTAG, account.getJid()
 169							+ ": using values from dns " + srvRecordServer
 170							+ "[" + srvIpServer + "]:" + srvRecordPort);
 171					socket = new Socket(srvIpServer, srvRecordPort);
 172				} else {
 173					boolean socketError = true;
 174					int srvIndex = 0;
 175					while (socketError && namePort.containsKey("name" + srvIndex)){
 176						try {
 177							srvRecordServer = namePort.getString("name" + srvIndex);
 178							srvRecordPort = namePort.getInt("port" + srvIndex);
 179							Log.d(Config.LOGTAG, account.getJid()
 180									+ ": using values from dns " + srvRecordServer
 181									+ ":" + srvRecordPort);
 182							socket = new Socket(srvRecordServer, srvRecordPort);
 183							socketError = false;
 184						} catch (UnknownHostException e) {
 185							srvIndex++;
 186						} catch (IOException e) {
 187							srvIndex++;
 188						}
 189					}
 190				}
 191			} else if (namePort.containsKey("error")
 192					&& "nosrv".equals(namePort.getString("error", null))) {
 193				socket = new Socket(account.getServer(), 5222);
 194			} else {
 195				Log.d(Config.LOGTAG, account.getJid()
 196						+ ": timeout in DNS resolution");
 197				changeStatus(Account.STATUS_OFFLINE);
 198				return;
 199			}
 200			OutputStream out = socket.getOutputStream();
 201			tagWriter.setOutputStream(out);
 202			InputStream in = socket.getInputStream();
 203			tagReader.setInputStream(in);
 204			tagWriter.beginDocument();
 205			sendStartStream();
 206			Tag nextTag;
 207			while ((nextTag = tagReader.readTag()) != null) {
 208				if (nextTag.isStart("stream")) {
 209					processStream(nextTag);
 210					break;
 211				} else {
 212					Log.d(Config.LOGTAG,
 213							"found unexpected tag: " + nextTag.getName());
 214					return;
 215				}
 216			}
 217			if (socket.isConnected()) {
 218				socket.close();
 219			}
 220		} catch (UnknownHostException e) {
 221			this.changeStatus(Account.STATUS_SERVER_NOT_FOUND);
 222			if (wakeLock.isHeld()) {
 223				try {
 224					wakeLock.release();
 225				} catch (RuntimeException re) {
 226				}
 227			}
 228			return;
 229		} catch (IOException e) {
 230			this.changeStatus(Account.STATUS_OFFLINE);
 231			if (wakeLock.isHeld()) {
 232				try {
 233					wakeLock.release();
 234				} catch (RuntimeException re) {
 235				}
 236			}
 237			return;
 238		} catch (NoSuchAlgorithmException e) {
 239			this.changeStatus(Account.STATUS_OFFLINE);
 240			Log.d(Config.LOGTAG, "compression exception " + e.getMessage());
 241			if (wakeLock.isHeld()) {
 242				try {
 243					wakeLock.release();
 244				} catch (RuntimeException re) {
 245				}
 246			}
 247			return;
 248		} catch (XmlPullParserException e) {
 249			this.changeStatus(Account.STATUS_OFFLINE);
 250			Log.d(Config.LOGTAG, "xml exception " + e.getMessage());
 251			if (wakeLock.isHeld()) {
 252				try {
 253					wakeLock.release();
 254				} catch (RuntimeException re) {
 255				}
 256			}
 257			return;
 258		}
 259
 260	}
 261
 262	@Override
 263	public void run() {
 264		connect();
 265	}
 266
 267	private void processStream(Tag currentTag) throws XmlPullParserException,
 268			IOException, NoSuchAlgorithmException {
 269		Tag nextTag = tagReader.readTag();
 270		while ((nextTag != null) && (!nextTag.isEnd("stream"))) {
 271			if (nextTag.isStart("error")) {
 272				processStreamError(nextTag);
 273			} else if (nextTag.isStart("features")) {
 274				processStreamFeatures(nextTag);
 275			} else if (nextTag.isStart("proceed")) {
 276				switchOverToTls(nextTag);
 277			} else if (nextTag.isStart("compressed")) {
 278				switchOverToZLib(nextTag);
 279			} else if (nextTag.isStart("success")) {
 280				Log.d(Config.LOGTAG, account.getJid() + ": logged in");
 281				tagReader.readTag();
 282				tagReader.reset();
 283				sendStartStream();
 284				processStream(tagReader.readTag());
 285				break;
 286			} else if (nextTag.isStart("failure")) {
 287				tagReader.readElement(nextTag);
 288				changeStatus(Account.STATUS_UNAUTHORIZED);
 289			} else if (nextTag.isStart("challenge")) {
 290				String challange = tagReader.readElement(nextTag).getContent();
 291				Element response = new Element("response");
 292				response.setAttribute("xmlns",
 293						"urn:ietf:params:xml:ns:xmpp-sasl");
 294				response.setContent(CryptoHelper.saslDigestMd5(account,
 295						challange, mRandom));
 296				tagWriter.writeElement(response);
 297			} else if (nextTag.isStart("enabled")) {
 298				Element enabled = tagReader.readElement(nextTag);
 299				if ("true".equals(enabled.getAttribute("resume"))) {
 300					this.streamId = enabled.getAttribute("id");
 301					Log.d(Config.LOGTAG, account.getJid()
 302							+ ": stream managment(" + smVersion
 303							+ ") enabled (resumable)");
 304				} else {
 305					Log.d(Config.LOGTAG, account.getJid()
 306							+ ": stream managment(" + smVersion + ") enabled");
 307				}
 308				this.lastSessionStarted = SystemClock.elapsedRealtime();
 309				this.stanzasReceived = 0;
 310				RequestPacket r = new RequestPacket(smVersion);
 311				tagWriter.writeStanzaAsync(r);
 312			} else if (nextTag.isStart("resumed")) {
 313				lastPaketReceived = SystemClock.elapsedRealtime();
 314				Element resumed = tagReader.readElement(nextTag);
 315				String h = resumed.getAttribute("h");
 316				try {
 317					int serverCount = Integer.parseInt(h);
 318					if (serverCount != stanzasSent) {
 319						Log.d(Config.LOGTAG, account.getJid()
 320								+ ": session resumed with lost packages");
 321						stanzasSent = serverCount;
 322					} else {
 323						Log.d(Config.LOGTAG, account.getJid()
 324								+ ": session resumed");
 325					}
 326					if (acknowledgedListener != null) {
 327						for (int i = 0; i < messageReceipts.size(); ++i) {
 328							if (serverCount >= messageReceipts.keyAt(i)) {
 329								acknowledgedListener.onMessageAcknowledged(
 330										account, messageReceipts.valueAt(i));
 331							}
 332						}
 333					}
 334					messageReceipts.clear();
 335				} catch (NumberFormatException e) {
 336
 337				}
 338				sendInitialPing();
 339
 340			} else if (nextTag.isStart("r")) {
 341				tagReader.readElement(nextTag);
 342				AckPacket ack = new AckPacket(this.stanzasReceived, smVersion);
 343				tagWriter.writeStanzaAsync(ack);
 344			} else if (nextTag.isStart("a")) {
 345				Element ack = tagReader.readElement(nextTag);
 346				lastPaketReceived = SystemClock.elapsedRealtime();
 347				int serverSequence = Integer.parseInt(ack.getAttribute("h"));
 348				String msgId = this.messageReceipts.get(serverSequence);
 349				if (msgId != null) {
 350					if (this.acknowledgedListener != null) {
 351						this.acknowledgedListener.onMessageAcknowledged(
 352								account, msgId);
 353					}
 354					this.messageReceipts.remove(serverSequence);
 355				}
 356			} else if (nextTag.isStart("failed")) {
 357				tagReader.readElement(nextTag);
 358				Log.d(Config.LOGTAG, account.getJid() + ": resumption failed");
 359				streamId = null;
 360				if (account.getStatus() != Account.STATUS_ONLINE) {
 361					sendBindRequest();
 362				}
 363			} else if (nextTag.isStart("iq")) {
 364				processIq(nextTag);
 365			} else if (nextTag.isStart("message")) {
 366				processMessage(nextTag);
 367			} else if (nextTag.isStart("presence")) {
 368				processPresence(nextTag);
 369			}
 370			nextTag = tagReader.readTag();
 371		}
 372		if (account.getStatus() == Account.STATUS_ONLINE) {
 373			account.setStatus(Account.STATUS_OFFLINE);
 374			if (statusListener != null) {
 375				statusListener.onStatusChanged(account);
 376			}
 377		}
 378	}
 379
 380	private void sendInitialPing() {
 381		Log.d(Config.LOGTAG, account.getJid() + ": sending intial ping");
 382		IqPacket iq = new IqPacket(IqPacket.TYPE_GET);
 383		iq.setFrom(account.getFullJid());
 384		iq.addChild("ping", "urn:xmpp:ping");
 385		this.sendIqPacket(iq, new OnIqPacketReceived() {
 386
 387            @Override
 388            public void onIqPacketReceived(Account account, IqPacket packet) {
 389                Log.d(Config.LOGTAG, account.getJid()
 390                        + ": online with resource " + account.getResource());
 391                changeStatus(Account.STATUS_ONLINE);
 392            }
 393        });
 394	}
 395
 396	private Element processPacket(Tag currentTag, int packetType)
 397			throws XmlPullParserException, IOException {
 398		Element element;
 399		switch (packetType) {
 400		case PACKET_IQ:
 401			element = new IqPacket();
 402			break;
 403		case PACKET_MESSAGE:
 404			element = new MessagePacket();
 405			break;
 406		case PACKET_PRESENCE:
 407			element = new PresencePacket();
 408			break;
 409		default:
 410			return null;
 411		}
 412		element.setAttributes(currentTag.getAttributes());
 413		Tag nextTag = tagReader.readTag();
 414		if (nextTag == null) {
 415			throw new IOException("interrupted mid tag");
 416		}
 417		while (!nextTag.isEnd(element.getName())) {
 418			if (!nextTag.isNo()) {
 419				Element child = tagReader.readElement(nextTag);
 420				String type = currentTag.getAttribute("type");
 421				if (packetType == PACKET_IQ
 422						&& "jingle".equals(child.getName())
 423						&& ("set".equalsIgnoreCase(type) || "get"
 424								.equalsIgnoreCase(type))) {
 425					element = new JinglePacket();
 426					element.setAttributes(currentTag.getAttributes());
 427				}
 428				element.addChild(child);
 429			}
 430			nextTag = tagReader.readTag();
 431			if (nextTag == null) {
 432				throw new IOException("interrupted mid tag");
 433			}
 434		}
 435		++stanzasReceived;
 436		lastPaketReceived = SystemClock.elapsedRealtime();
 437		return element;
 438	}
 439
 440	private void processIq(Tag currentTag) throws XmlPullParserException,
 441			IOException {
 442		IqPacket packet = (IqPacket) processPacket(currentTag, PACKET_IQ);
 443
 444		if (packet.getId() == null) {
 445			return; // an iq packet without id is definitely invalid
 446		}
 447
 448		if (packet instanceof JinglePacket) {
 449			if (this.jingleListener != null) {
 450				this.jingleListener.onJinglePacketReceived(account,
 451						(JinglePacket) packet);
 452			}
 453		} else {
 454			if (packetCallbacks.containsKey(packet.getId())) {
 455				if (packetCallbacks.get(packet.getId()) instanceof OnIqPacketReceived) {
 456					((OnIqPacketReceived) packetCallbacks.get(packet.getId()))
 457							.onIqPacketReceived(account, packet);
 458				}
 459
 460				packetCallbacks.remove(packet.getId());
 461			} else if ((packet.getType() == IqPacket.TYPE_GET || packet
 462					.getType() == IqPacket.TYPE_SET)
 463					&& this.unregisteredIqListener != null) {
 464				this.unregisteredIqListener.onIqPacketReceived(account, packet);
 465			}
 466		}
 467	}
 468
 469	private void processMessage(Tag currentTag) throws XmlPullParserException,
 470			IOException {
 471		MessagePacket packet = (MessagePacket) processPacket(currentTag,
 472				PACKET_MESSAGE);
 473		String id = packet.getAttribute("id");
 474		if ((id != null) && (packetCallbacks.containsKey(id))) {
 475			if (packetCallbacks.get(id) instanceof OnMessagePacketReceived) {
 476				((OnMessagePacketReceived) packetCallbacks.get(id))
 477						.onMessagePacketReceived(account, packet);
 478			}
 479			packetCallbacks.remove(id);
 480		} else if (this.messageListener != null) {
 481			this.messageListener.onMessagePacketReceived(account, packet);
 482		}
 483	}
 484
 485	private void processPresence(Tag currentTag) throws XmlPullParserException,
 486			IOException {
 487		PresencePacket packet = (PresencePacket) processPacket(currentTag,
 488				PACKET_PRESENCE);
 489		String id = packet.getAttribute("id");
 490		if ((id != null) && (packetCallbacks.containsKey(id))) {
 491			if (packetCallbacks.get(id) instanceof OnPresencePacketReceived) {
 492				((OnPresencePacketReceived) packetCallbacks.get(id))
 493						.onPresencePacketReceived(account, packet);
 494			}
 495			packetCallbacks.remove(id);
 496		} else if (this.presenceListener != null) {
 497			this.presenceListener.onPresencePacketReceived(account, packet);
 498		}
 499	}
 500
 501	private void sendCompressionZlib() throws IOException {
 502		Element compress = new Element("compress");
 503		compress.setAttribute("xmlns", "http://jabber.org/protocol/compress");
 504		compress.addChild("method").setContent("zlib");
 505		tagWriter.writeElement(compress);
 506	}
 507
 508	private void switchOverToZLib(Tag currentTag)
 509			throws XmlPullParserException, IOException,
 510			NoSuchAlgorithmException {
 511		tagReader.readTag(); // read tag close
 512		tagWriter.setOutputStream(new ZLibOutputStream(tagWriter
 513				.getOutputStream()));
 514		tagReader
 515				.setInputStream(new ZLibInputStream(tagReader.getInputStream()));
 516
 517		sendStartStream();
 518		Log.d(Config.LOGTAG, account.getJid() + ": compression enabled");
 519		usingCompression = true;
 520		processStream(tagReader.readTag());
 521	}
 522
 523	private void sendStartTLS() throws IOException {
 524		Tag startTLS = Tag.empty("starttls");
 525		startTLS.setAttribute("xmlns", "urn:ietf:params:xml:ns:xmpp-tls");
 526		tagWriter.writeTag(startTLS);
 527	}
 528
 529	private SharedPreferences getPreferences() {
 530		return PreferenceManager.getDefaultSharedPreferences(applicationContext);
 531	}
 532
 533	private boolean enableLegacySSL() {
 534		return getPreferences().getBoolean("enable_legacy_ssl", false);
 535	}
 536
 537	private void switchOverToTls(Tag currentTag) throws XmlPullParserException,
 538			IOException {
 539		tagReader.readTag();
 540		try {
 541			SSLContext sc = SSLContext.getInstance("TLS");
 542			sc.init(null,
 543					new X509TrustManager[] { this.mMemorizingTrustManager },
 544					mRandom);
 545			SSLSocketFactory factory = sc.getSocketFactory();
 546
 547			HostnameVerifier verifier = this.mMemorizingTrustManager
 548					.wrapHostnameVerifier(new org.apache.http.conn.ssl.StrictHostnameVerifier());
 549			SSLSocket sslSocket = (SSLSocket) factory.createSocket(socket,
 550					socket.getInetAddress().getHostAddress(), socket.getPort(),
 551					true);
 552
 553			// Support all protocols except legacy SSL.
 554			// The min SDK version prevents us having to worry about SSLv2. In future, this may be
 555			// true of SSLv3 as well.
 556			final String[] supportProtocols;
 557			if (enableLegacySSL()) {
 558				supportProtocols = sslSocket.getSupportedProtocols();
 559			} else {
 560				final List<String> supportedProtocols = new LinkedList<String>(Arrays.asList(
 561							sslSocket.getSupportedProtocols()));
 562				supportedProtocols.remove("SSLv3");
 563				supportProtocols = new String[supportedProtocols.size()];
 564				supportedProtocols.toArray(supportProtocols);
 565			}
 566			sslSocket.setEnabledProtocols(supportProtocols);
 567
 568			if (verifier != null
 569					&& !verifier.verify(account.getServer(),
 570							sslSocket.getSession())) {
 571				Log.d(Config.LOGTAG, account.getJid()
 572						+ ": host mismatch in TLS connection");
 573				sslSocket.close();
 574				throw new IOException();
 575			}
 576			tagReader.setInputStream(sslSocket.getInputStream());
 577			tagWriter.setOutputStream(sslSocket.getOutputStream());
 578			sendStartStream();
 579			Log.d(Config.LOGTAG, account.getJid()
 580					+ ": TLS connection established");
 581			usingEncryption = true;
 582			processStream(tagReader.readTag());
 583			sslSocket.close();
 584		} catch (NoSuchAlgorithmException e1) {
 585			e1.printStackTrace();
 586		} catch (KeyManagementException e) {
 587			e.printStackTrace();
 588		}
 589	}
 590
 591	private void sendSaslAuthPlain() throws IOException {
 592		String saslString = CryptoHelper.saslPlain(account.getUsername(),
 593				account.getPassword());
 594		Element auth = new Element("auth");
 595		auth.setAttribute("xmlns", "urn:ietf:params:xml:ns:xmpp-sasl");
 596		auth.setAttribute("mechanism", "PLAIN");
 597		auth.setContent(saslString);
 598		tagWriter.writeElement(auth);
 599	}
 600
 601	private void sendSaslAuthDigestMd5() throws IOException {
 602		Element auth = new Element("auth");
 603		auth.setAttribute("xmlns", "urn:ietf:params:xml:ns:xmpp-sasl");
 604		auth.setAttribute("mechanism", "DIGEST-MD5");
 605		tagWriter.writeElement(auth);
 606	}
 607
 608	private void processStreamFeatures(Tag currentTag)
 609			throws XmlPullParserException, IOException {
 610		this.streamFeatures = tagReader.readElement(currentTag);
 611		if (this.streamFeatures.hasChild("starttls") && !usingEncryption) {
 612			sendStartTLS();
 613		} else if (compressionAvailable()) {
 614			sendCompressionZlib();
 615		} else if (this.streamFeatures.hasChild("register")
 616				&& account.isOptionSet(Account.OPTION_REGISTER) && usingEncryption) {
 617			sendRegistryRequest();
 618		} else if (!this.streamFeatures.hasChild("register")
 619				&& account.isOptionSet(Account.OPTION_REGISTER)) {
 620			changeStatus(Account.STATUS_REGISTRATION_NOT_SUPPORTED);
 621			disconnect(true);
 622		} else if (this.streamFeatures.hasChild("mechanisms")
 623				&& shouldAuthenticate && usingEncryption) {
 624			List<String> mechanisms = extractMechanisms(streamFeatures
 625					.findChild("mechanisms"));
 626			if (mechanisms.contains("PLAIN")) {
 627				sendSaslAuthPlain();
 628			} else if (mechanisms.contains("DIGEST-MD5")) {
 629				sendSaslAuthDigestMd5();
 630			}
 631		} else if (this.streamFeatures.hasChild("sm", "urn:xmpp:sm:"
 632				+ smVersion)
 633				&& streamId != null) {
 634			ResumePacket resume = new ResumePacket(this.streamId,
 635					stanzasReceived, smVersion);
 636			this.tagWriter.writeStanzaAsync(resume);
 637		} else if (this.streamFeatures.hasChild("bind") && shouldBind) {
 638			sendBindRequest();
 639		} else {
 640			Log.d(Config.LOGTAG,account.getJid()+": incompatible server. disconnecting");
 641			disconnect(true);
 642		}
 643	}
 644
 645	private boolean compressionAvailable() {
 646		if (!this.streamFeatures.hasChild("compression",
 647				"http://jabber.org/features/compress"))
 648			return false;
 649		if (!ZLibOutputStream.SUPPORTED)
 650			return false;
 651		if (!account.isOptionSet(Account.OPTION_USECOMPRESSION))
 652			return false;
 653
 654		Element compression = this.streamFeatures.findChild("compression",
 655				"http://jabber.org/features/compress");
 656		for (Element child : compression.getChildren()) {
 657			if (!"method".equals(child.getName()))
 658				continue;
 659
 660			if ("zlib".equalsIgnoreCase(child.getContent())) {
 661				return true;
 662			}
 663		}
 664		return false;
 665	}
 666
 667	private List<String> extractMechanisms(Element stream) {
 668		ArrayList<String> mechanisms = new ArrayList<String>(stream
 669				.getChildren().size());
 670		for (Element child : stream.getChildren()) {
 671			mechanisms.add(child.getContent());
 672		}
 673		return mechanisms;
 674	}
 675
 676	private void sendRegistryRequest() {
 677		IqPacket register = new IqPacket(IqPacket.TYPE_GET);
 678		register.query("jabber:iq:register");
 679		register.setTo(account.getServer());
 680		sendIqPacket(register, new OnIqPacketReceived() {
 681
 682			@Override
 683			public void onIqPacketReceived(Account account, IqPacket packet) {
 684				Element instructions = packet.query().findChild("instructions");
 685				if (packet.query().hasChild("username")
 686						&& (packet.query().hasChild("password"))) {
 687					IqPacket register = new IqPacket(IqPacket.TYPE_SET);
 688					Element username = new Element("username")
 689							.setContent(account.getUsername());
 690					Element password = new Element("password")
 691							.setContent(account.getPassword());
 692					register.query("jabber:iq:register").addChild(username);
 693					register.query().addChild(password);
 694					sendIqPacket(register, new OnIqPacketReceived() {
 695
 696						@Override
 697						public void onIqPacketReceived(Account account,
 698								IqPacket packet) {
 699							if (packet.getType() == IqPacket.TYPE_RESULT) {
 700								account.setOption(Account.OPTION_REGISTER,
 701										false);
 702								changeStatus(Account.STATUS_REGISTRATION_SUCCESSFULL);
 703							} else if (packet.hasChild("error")
 704									&& (packet.findChild("error")
 705											.hasChild("conflict"))) {
 706								changeStatus(Account.STATUS_REGISTRATION_CONFLICT);
 707							} else {
 708								changeStatus(Account.STATUS_REGISTRATION_FAILED);
 709								Log.d(Config.LOGTAG, packet.toString());
 710							}
 711							disconnect(true);
 712						}
 713					});
 714				} else {
 715					changeStatus(Account.STATUS_REGISTRATION_FAILED);
 716					disconnect(true);
 717					Log.d(Config.LOGTAG, account.getJid()
 718							+ ": could not register. instructions are"
 719							+ instructions.getContent());
 720				}
 721			}
 722		});
 723	}
 724
 725	private void sendBindRequest() throws IOException {
 726		IqPacket iq = new IqPacket(IqPacket.TYPE_SET);
 727		iq.addChild("bind", "urn:ietf:params:xml:ns:xmpp-bind")
 728				.addChild("resource").setContent(account.getResource());
 729		this.sendUnboundIqPacket(iq, new OnIqPacketReceived() {
 730			@Override
 731			public void onIqPacketReceived(Account account, IqPacket packet) {
 732				Element bind = packet.findChild("bind");
 733				if (bind != null) {
 734					Element jid = bind.findChild("jid");
 735					if (jid != null && jid.getContent() != null) {
 736						account.setResource(jid.getContent().split("/", 2)[1]);
 737						if (streamFeatures.hasChild("sm", "urn:xmpp:sm:3")) {
 738							smVersion = 3;
 739							EnablePacket enable = new EnablePacket(smVersion);
 740							tagWriter.writeStanzaAsync(enable);
 741							stanzasSent = 0;
 742							messageReceipts.clear();
 743						} else if (streamFeatures.hasChild("sm",
 744								"urn:xmpp:sm:2")) {
 745							smVersion = 2;
 746							EnablePacket enable = new EnablePacket(smVersion);
 747							tagWriter.writeStanzaAsync(enable);
 748							stanzasSent = 0;
 749							messageReceipts.clear();
 750						}
 751						sendServiceDiscoveryInfo(account.getServer());
 752						sendServiceDiscoveryItems(account.getServer());
 753						if (bindListener != null) {
 754							bindListener.onBind(account);
 755						}
 756						sendInitialPing();
 757					} else {
 758						disconnect(true);
 759					}
 760				} else {
 761					disconnect(true);
 762				}
 763			}
 764		});
 765		if (this.streamFeatures.hasChild("session")) {
 766			Log.d(Config.LOGTAG, account.getJid()
 767					+ ": sending deprecated session");
 768			IqPacket startSession = new IqPacket(IqPacket.TYPE_SET);
 769			startSession.addChild("session",
 770					"urn:ietf:params:xml:ns:xmpp-session");
 771			this.sendUnboundIqPacket(startSession, null);
 772		}
 773	}
 774
 775	private void sendServiceDiscoveryInfo(final String server) {
 776		IqPacket iq = new IqPacket(IqPacket.TYPE_GET);
 777		iq.setTo(server);
 778		iq.query("http://jabber.org/protocol/disco#info");
 779		this.sendIqPacket(iq, new OnIqPacketReceived() {
 780
 781			@Override
 782			public void onIqPacketReceived(Account account, IqPacket packet) {
 783				List<Element> elements = packet.query().getChildren();
 784				List<String> features = new ArrayList<String>();
 785				for (int i = 0; i < elements.size(); ++i) {
 786					if (elements.get(i).getName().equals("feature")) {
 787						features.add(elements.get(i).getAttribute("var"));
 788					}
 789				}
 790				disco.put(server, features);
 791
 792				if (account.getServer().equals(server)) {
 793					enableAdvancedStreamFeatures();
 794				}
 795			}
 796		});
 797	}
 798
 799	private void enableAdvancedStreamFeatures() {
 800		if (getFeatures().carbons()) {
 801			sendEnableCarbons();
 802		}
 803	}
 804
 805	private void sendServiceDiscoveryItems(final String server) {
 806		IqPacket iq = new IqPacket(IqPacket.TYPE_GET);
 807		iq.setTo(server);
 808		iq.query("http://jabber.org/protocol/disco#items");
 809		this.sendIqPacket(iq, new OnIqPacketReceived() {
 810
 811			@Override
 812			public void onIqPacketReceived(Account account, IqPacket packet) {
 813				List<Element> elements = packet.query().getChildren();
 814				for (int i = 0; i < elements.size(); ++i) {
 815					if (elements.get(i).getName().equals("item")) {
 816						String jid = elements.get(i).getAttribute("jid");
 817						sendServiceDiscoveryInfo(jid);
 818					}
 819				}
 820			}
 821		});
 822	}
 823
 824	private void sendEnableCarbons() {
 825		IqPacket iq = new IqPacket(IqPacket.TYPE_SET);
 826		iq.addChild("enable", "urn:xmpp:carbons:2");
 827		this.sendIqPacket(iq, new OnIqPacketReceived() {
 828
 829			@Override
 830			public void onIqPacketReceived(Account account, IqPacket packet) {
 831				if (!packet.hasChild("error")) {
 832					Log.d(Config.LOGTAG, account.getJid()
 833							+ ": successfully enabled carbons");
 834				} else {
 835					Log.d(Config.LOGTAG, account.getJid()
 836							+ ": error enableing carbons " + packet.toString());
 837				}
 838			}
 839		});
 840	}
 841
 842	private void processStreamError(Tag currentTag)
 843			throws XmlPullParserException, IOException {
 844		Element streamError = tagReader.readElement(currentTag);
 845		if (streamError != null && streamError.hasChild("conflict")) {
 846			String resource = account.getResource().split("\\.")[0];
 847			account.setResource(resource + "." + nextRandomId());
 848			Log.d(Config.LOGTAG,
 849					account.getJid() + ": switching resource due to conflict ("
 850							+ account.getResource() + ")");
 851		}
 852	}
 853
 854	private void sendStartStream() throws IOException {
 855		Tag stream = Tag.start("stream:stream");
 856		stream.setAttribute("from", account.getJid());
 857		stream.setAttribute("to", account.getServer());
 858		stream.setAttribute("version", "1.0");
 859		stream.setAttribute("xml:lang", "en");
 860		stream.setAttribute("xmlns", "jabber:client");
 861		stream.setAttribute("xmlns:stream", "http://etherx.jabber.org/streams");
 862		tagWriter.writeTag(stream);
 863	}
 864
 865	private String nextRandomId() {
 866		return new BigInteger(50, mRandom).toString(32);
 867	}
 868
 869	public void sendIqPacket(IqPacket packet, OnIqPacketReceived callback) {
 870		if (packet.getId() == null) {
 871			String id = nextRandomId();
 872			packet.setAttribute("id", id);
 873		}
 874		packet.setFrom(account.getFullJid());
 875		this.sendPacket(packet, callback);
 876	}
 877
 878	public void sendUnboundIqPacket(IqPacket packet, OnIqPacketReceived callback) {
 879		if (packet.getId() == null) {
 880			String id = nextRandomId();
 881			packet.setAttribute("id", id);
 882		}
 883		this.sendPacket(packet, callback);
 884	}
 885
 886	public void sendMessagePacket(MessagePacket packet) {
 887		this.sendPacket(packet, null);
 888	}
 889
 890	public void sendPresencePacket(PresencePacket packet) {
 891		this.sendPacket(packet, null);
 892	}
 893
 894	private synchronized void sendPacket(final AbstractStanza packet,
 895			PacketReceived callback) {
 896		if (packet.getName().equals("iq") || packet.getName().equals("message")
 897				|| packet.getName().equals("presence")) {
 898			++stanzasSent;
 899		}
 900		tagWriter.writeStanzaAsync(packet);
 901		if (packet instanceof MessagePacket && packet.getId() != null
 902				&& this.streamId != null) {
 903			Log.d(Config.LOGTAG, "request delivery report for stanza "
 904					+ stanzasSent);
 905			this.messageReceipts.put(stanzasSent, packet.getId());
 906			tagWriter.writeStanzaAsync(new RequestPacket(this.smVersion));
 907		}
 908		if (callback != null) {
 909			if (packet.getId() == null) {
 910				packet.setId(nextRandomId());
 911			}
 912			packetCallbacks.put(packet.getId(), callback);
 913		}
 914	}
 915
 916	public void sendPing() {
 917		if (streamFeatures.hasChild("sm")) {
 918			tagWriter.writeStanzaAsync(new RequestPacket(smVersion));
 919		} else {
 920			IqPacket iq = new IqPacket(IqPacket.TYPE_GET);
 921			iq.setFrom(account.getFullJid());
 922			iq.addChild("ping", "urn:xmpp:ping");
 923			this.sendIqPacket(iq, null);
 924		}
 925		this.lastPingSent = SystemClock.elapsedRealtime();
 926	}
 927
 928	public void setOnMessagePacketReceivedListener(
 929			OnMessagePacketReceived listener) {
 930		this.messageListener = listener;
 931	}
 932
 933	public void setOnUnregisteredIqPacketReceivedListener(
 934			OnIqPacketReceived listener) {
 935		this.unregisteredIqListener = listener;
 936	}
 937
 938	public void setOnPresencePacketReceivedListener(
 939			OnPresencePacketReceived listener) {
 940		this.presenceListener = listener;
 941	}
 942
 943	public void setOnJinglePacketReceivedListener(
 944			OnJinglePacketReceived listener) {
 945		this.jingleListener = listener;
 946	}
 947
 948	public void setOnStatusChangedListener(OnStatusChanged listener) {
 949		this.statusListener = listener;
 950	}
 951
 952	public void setOnBindListener(OnBindListener listener) {
 953		this.bindListener = listener;
 954	}
 955
 956	public void setOnMessageAcknowledgeListener(OnMessageAcknowledged listener) {
 957		this.acknowledgedListener = listener;
 958	}
 959
 960	public void disconnect(boolean force) {
 961		Log.d(Config.LOGTAG, account.getJid() + ": disconnecting");
 962		try {
 963			if (force) {
 964				socket.close();
 965				return;
 966			}
 967			new Thread(new Runnable() {
 968
 969				@Override
 970				public void run() {
 971					if (tagWriter.isActive()) {
 972						tagWriter.finish();
 973						try {
 974							while (!tagWriter.finished()) {
 975								Log.d(Config.LOGTAG, "not yet finished");
 976								Thread.sleep(100);
 977							}
 978							tagWriter.writeTag(Tag.end("stream:stream"));
 979							socket.close();
 980						} catch (IOException e) {
 981							Log.d(Config.LOGTAG,
 982									"io exception during disconnect");
 983						} catch (InterruptedException e) {
 984							Log.d(Config.LOGTAG, "interrupted");
 985						}
 986					}
 987				}
 988			}).start();
 989		} catch (IOException e) {
 990			Log.d(Config.LOGTAG, "io exception during disconnect");
 991		}
 992	}
 993
 994	public List<String> findDiscoItemsByFeature(String feature) {
 995		List<String> items = new ArrayList<String>();
 996		for (Entry<String, List<String>> cursor : disco.entrySet()) {
 997			if (cursor.getValue().contains(feature)) {
 998				items.add(cursor.getKey());
 999			}
1000		}
1001		return items;
1002	}
1003
1004	public String findDiscoItemByFeature(String feature) {
1005		List<String> items = findDiscoItemsByFeature(feature);
1006		if (items.size() >= 1) {
1007			return items.get(0);
1008		}
1009		return null;
1010	}
1011
1012	public void r() {
1013		this.tagWriter.writeStanzaAsync(new RequestPacket(smVersion));
1014	}
1015
1016	public String getMucServer() {
1017		return findDiscoItemByFeature("http://jabber.org/protocol/muc");
1018	}
1019
1020	public int getTimeToNextAttempt() {
1021		int interval = (int) (25 * Math.pow(1.5, attempt));
1022		int secondsSinceLast = (int) ((SystemClock.elapsedRealtime() - this.lastConnect) / 1000);
1023		return interval - secondsSinceLast;
1024	}
1025
1026	public int getAttempt() {
1027		return this.attempt;
1028	}
1029
1030	public Features getFeatures() {
1031		return this.features;
1032	}
1033
1034	public class Features {
1035		XmppConnection connection;
1036
1037		public Features(XmppConnection connection) {
1038			this.connection = connection;
1039		}
1040
1041		private boolean hasDiscoFeature(String server, String feature) {
1042			if (!connection.disco.containsKey(server)) {
1043				return false;
1044			}
1045			return connection.disco.get(server).contains(feature);
1046		}
1047
1048		public boolean carbons() {
1049			return hasDiscoFeature(account.getServer(), "urn:xmpp:carbons:2");
1050		}
1051
1052		public boolean sm() {
1053			return streamId != null;
1054		}
1055
1056		public boolean csi() {
1057			if (connection.streamFeatures == null) {
1058				return false;
1059			} else {
1060				return connection.streamFeatures.hasChild("csi",
1061						"urn:xmpp:csi:0");
1062			}
1063		}
1064
1065		public boolean pubsub() {
1066			return hasDiscoFeature(account.getServer(),
1067					"http://jabber.org/protocol/pubsub#publish");
1068		}
1069
1070		public boolean rosterVersioning() {
1071			if (connection.streamFeatures == null) {
1072				return false;
1073			} else {
1074				return connection.streamFeatures.hasChild("ver");
1075			}
1076		}
1077
1078		public boolean streamhost() {
1079			return connection
1080					.findDiscoItemByFeature("http://jabber.org/protocol/bytestreams") != null;
1081		}
1082
1083		public boolean compression() {
1084			return connection.usingCompression;
1085		}
1086	}
1087
1088	public long getLastSessionEstablished() {
1089		long diff;
1090		if (this.lastSessionStarted == 0) {
1091			diff = SystemClock.elapsedRealtime() - this.lastConnect;
1092		} else {
1093			diff = SystemClock.elapsedRealtime() - this.lastSessionStarted;
1094		}
1095		return System.currentTimeMillis() - diff;
1096	}
1097
1098	public long getLastConnect() {
1099		return this.lastConnect;
1100	}
1101
1102	public long getLastPingSent() {
1103		return this.lastPingSent;
1104	}
1105
1106	public long getLastPacketReceived() {
1107		return this.lastPaketReceived;
1108	}
1109
1110	public void sendActive() {
1111		this.sendPacket(new ActivePacket(), null);
1112	}
1113
1114	public void sendInactive() {
1115		this.sendPacket(new InactivePacket(), null);
1116	}
1117}