1package eu.siacs.conversations.xmpp;
   2
   3import android.graphics.Bitmap;
   4import android.graphics.BitmapFactory;
   5import android.os.Bundle;
   6import android.os.Parcelable;
   7import android.os.PowerManager;
   8import android.os.PowerManager.WakeLock;
   9import android.os.SystemClock;
  10import android.security.KeyChain;
  11import android.util.Base64;
  12import android.util.Log;
  13import android.util.Pair;
  14import android.util.SparseArray;
  15
  16import org.json.JSONException;
  17import org.json.JSONObject;
  18import org.xmlpull.v1.XmlPullParserException;
  19
  20import java.io.ByteArrayInputStream;
  21import java.io.IOException;
  22import java.io.InputStream;
  23import java.math.BigInteger;
  24import java.net.ConnectException;
  25import java.net.IDN;
  26import java.net.InetAddress;
  27import java.net.InetSocketAddress;
  28import java.net.Socket;
  29import java.net.UnknownHostException;
  30import java.net.URL;
  31import java.security.KeyManagementException;
  32import java.security.NoSuchAlgorithmException;
  33import java.security.Principal;
  34import java.security.PrivateKey;
  35import java.security.cert.X509Certificate;
  36import java.util.ArrayList;
  37import java.util.HashMap;
  38import java.util.Hashtable;
  39import java.util.Iterator;
  40import java.util.List;
  41import java.util.Map.Entry;
  42
  43import javax.net.ssl.HostnameVerifier;
  44import javax.net.ssl.KeyManager;
  45import javax.net.ssl.SSLContext;
  46import javax.net.ssl.SSLSocket;
  47import javax.net.ssl.SSLSocketFactory;
  48import javax.net.ssl.X509KeyManager;
  49import javax.net.ssl.X509TrustManager;
  50
  51import de.duenndns.ssl.MemorizingTrustManager;
  52import eu.siacs.conversations.Config;
  53import eu.siacs.conversations.crypto.XmppDomainVerifier;
  54import eu.siacs.conversations.crypto.sasl.DigestMd5;
  55import eu.siacs.conversations.crypto.sasl.External;
  56import eu.siacs.conversations.crypto.sasl.Plain;
  57import eu.siacs.conversations.crypto.sasl.SaslMechanism;
  58import eu.siacs.conversations.crypto.sasl.ScramSha1;
  59import eu.siacs.conversations.entities.Account;
  60import eu.siacs.conversations.entities.Message;
  61import eu.siacs.conversations.entities.ServiceDiscoveryResult;
  62import eu.siacs.conversations.generator.IqGenerator;
  63import eu.siacs.conversations.services.XmppConnectionService;
  64import eu.siacs.conversations.utils.CryptoHelper;
  65import eu.siacs.conversations.utils.DNSHelper;
  66import eu.siacs.conversations.utils.SSLSocketHelper;
  67import eu.siacs.conversations.utils.SocksSocketFactory;
  68import eu.siacs.conversations.utils.Xmlns;
  69import eu.siacs.conversations.xml.Element;
  70import eu.siacs.conversations.xml.Tag;
  71import eu.siacs.conversations.xml.TagWriter;
  72import eu.siacs.conversations.xml.XmlReader;
  73import eu.siacs.conversations.xmpp.forms.Data;
  74import eu.siacs.conversations.xmpp.forms.Field;
  75import eu.siacs.conversations.xmpp.jid.InvalidJidException;
  76import eu.siacs.conversations.xmpp.jid.Jid;
  77import eu.siacs.conversations.xmpp.jingle.OnJinglePacketReceived;
  78import eu.siacs.conversations.xmpp.jingle.stanzas.JinglePacket;
  79import eu.siacs.conversations.xmpp.stanzas.AbstractAcknowledgeableStanza;
  80import eu.siacs.conversations.xmpp.stanzas.AbstractStanza;
  81import eu.siacs.conversations.xmpp.stanzas.IqPacket;
  82import eu.siacs.conversations.xmpp.stanzas.MessagePacket;
  83import eu.siacs.conversations.xmpp.stanzas.PresencePacket;
  84import eu.siacs.conversations.xmpp.stanzas.csi.ActivePacket;
  85import eu.siacs.conversations.xmpp.stanzas.csi.InactivePacket;
  86import eu.siacs.conversations.xmpp.stanzas.streammgmt.AckPacket;
  87import eu.siacs.conversations.xmpp.stanzas.streammgmt.EnablePacket;
  88import eu.siacs.conversations.xmpp.stanzas.streammgmt.RequestPacket;
  89import eu.siacs.conversations.xmpp.stanzas.streammgmt.ResumePacket;
  90
  91public class XmppConnection implements Runnable {
  92
  93	private static final int PACKET_IQ = 0;
  94	private static final int PACKET_MESSAGE = 1;
  95	private static final int PACKET_PRESENCE = 2;
  96	protected Account account;
  97	private final WakeLock wakeLock;
  98	private Socket socket;
  99	private XmlReader tagReader;
 100	private TagWriter tagWriter;
 101	private final Features features = new Features(this);
 102	private boolean needsBinding = true;
 103	private boolean shouldAuthenticate = true;
 104	private Element streamFeatures;
 105	private final HashMap<Jid, ServiceDiscoveryResult> disco = new HashMap<>();
 106
 107	private String streamId = null;
 108	private int smVersion = 3;
 109	private final SparseArray<AbstractAcknowledgeableStanza> mStanzaQueue = new SparseArray<>();
 110
 111	private int stanzasReceived = 0;
 112	private int stanzasSent = 0;
 113	private long lastPacketReceived = 0;
 114	private long lastPingSent = 0;
 115	private long lastConnect = 0;
 116	private long lastSessionStarted = 0;
 117	private long lastDiscoStarted = 0;
 118	private int mPendingServiceDiscoveries = 0;
 119	private final ArrayList<String> mPendingServiceDiscoveriesIds = new ArrayList<>();
 120	private boolean mInteractive = false;
 121	private int attempt = 0;
 122	private final Hashtable<String, Pair<IqPacket, OnIqPacketReceived>> packetCallbacks = new Hashtable<>();
 123	private OnPresencePacketReceived presenceListener = null;
 124	private OnJinglePacketReceived jingleListener = null;
 125	private OnIqPacketReceived unregisteredIqListener = null;
 126	private OnMessagePacketReceived messageListener = null;
 127	private OnStatusChanged statusListener = null;
 128	private OnBindListener bindListener = null;
 129	private final ArrayList<OnAdvancedStreamFeaturesLoaded> advancedStreamFeaturesLoadedListeners = new ArrayList<>();
 130	private OnMessageAcknowledged acknowledgedListener = null;
 131	private XmppConnectionService mXmppConnectionService = null;
 132
 133	private SaslMechanism saslMechanism;
 134
 135	private X509KeyManager mKeyManager = new X509KeyManager() {
 136		@Override
 137		public String chooseClientAlias(String[] strings, Principal[] principals, Socket socket) {
 138			return account.getPrivateKeyAlias();
 139		}
 140
 141		@Override
 142		public String chooseServerAlias(String s, Principal[] principals, Socket socket) {
 143			return null;
 144		}
 145
 146		@Override
 147		public X509Certificate[] getCertificateChain(String alias) {
 148			try {
 149				return KeyChain.getCertificateChain(mXmppConnectionService, alias);
 150			} catch (Exception e) {
 151				return new X509Certificate[0];
 152			}
 153		}
 154
 155		@Override
 156		public String[] getClientAliases(String s, Principal[] principals) {
 157			return new String[0];
 158		}
 159
 160		@Override
 161		public String[] getServerAliases(String s, Principal[] principals) {
 162			return new String[0];
 163		}
 164
 165		@Override
 166		public PrivateKey getPrivateKey(String alias) {
 167			try {
 168				return KeyChain.getPrivateKey(mXmppConnectionService, alias);
 169			} catch (Exception e) {
 170				return null;
 171			}
 172		}
 173	};
 174	private Identity mServerIdentity = Identity.UNKNOWN;
 175
 176	private OnIqPacketReceived createPacketReceiveHandler() {
 177		return new OnIqPacketReceived() {
 178			@Override
 179			public void onIqPacketReceived(Account account, IqPacket packet) {
 180				if (packet.getType() == IqPacket.TYPE.RESULT) {
 181					account.setOption(Account.OPTION_REGISTER,
 182							false);
 183					changeStatus(Account.State.REGISTRATION_SUCCESSFUL);
 184				} else if (packet.hasChild("error")
 185						&& (packet.findChild("error")
 186						.hasChild("conflict"))) {
 187					changeStatus(Account.State.REGISTRATION_CONFLICT);
 188				} else {
 189					changeStatus(Account.State.REGISTRATION_FAILED);
 190					Log.d(Config.LOGTAG, packet.toString());
 191				}
 192				disconnect(true);
 193			}
 194		};
 195	}
 196
 197	public XmppConnection(final Account account, final XmppConnectionService service) {
 198		this.account = account;
 199		this.wakeLock = service.getPowerManager().newWakeLock(
 200				PowerManager.PARTIAL_WAKE_LOCK, account.getJid().toBareJid().toString());
 201		tagWriter = new TagWriter();
 202		mXmppConnectionService = service;
 203	}
 204
 205	protected void changeStatus(final Account.State nextStatus) {
 206		if (account.getStatus() != nextStatus) {
 207			if ((nextStatus == Account.State.OFFLINE)
 208					&& (account.getStatus() != Account.State.CONNECTING)
 209					&& (account.getStatus() != Account.State.ONLINE)
 210					&& (account.getStatus() != Account.State.DISABLED)) {
 211				return;
 212					}
 213			if (nextStatus == Account.State.ONLINE) {
 214				this.attempt = 0;
 215			}
 216			account.setStatus(nextStatus);
 217			if (statusListener != null) {
 218				statusListener.onStatusChanged(account);
 219			}
 220		}
 221	}
 222
 223	protected void connect() {
 224		Log.d(Config.LOGTAG, account.getJid().toBareJid().toString() + ": connecting");
 225		features.encryptionEnabled = false;
 226		lastConnect = SystemClock.elapsedRealtime();
 227		lastPingSent = SystemClock.elapsedRealtime();
 228		lastDiscoStarted = Long.MAX_VALUE;
 229		this.attempt++;
 230		switch (account.getJid().getDomainpart()) {
 231			case "chat.facebook.com":
 232				mServerIdentity = Identity.FACEBOOK;
 233				break;
 234			case "nimbuzz.com":
 235				mServerIdentity = Identity.NIMBUZZ;
 236				break;
 237			default:
 238				mServerIdentity = Identity.UNKNOWN;
 239				break;
 240		}
 241		try {
 242			shouldAuthenticate = needsBinding = !account.isOptionSet(Account.OPTION_REGISTER);
 243			tagReader = new XmlReader(wakeLock);
 244			tagWriter = new TagWriter();
 245			this.changeStatus(Account.State.CONNECTING);
 246			final boolean useTor = mXmppConnectionService.useTorToConnect() || account.isOnion();
 247			if (useTor) {
 248				String destination;
 249				if (account.getHostname() == null || account.getHostname().isEmpty()) {
 250					destination = account.getServer().toString();
 251				} else {
 252					destination = account.getHostname();
 253				}
 254				Log.d(Config.LOGTAG,account.getJid().toBareJid()+": connect to "+destination+" via TOR");
 255				socket = SocksSocketFactory.createSocketOverTor(destination,account.getPort());
 256				startXmpp();
 257			} else if (DNSHelper.isIp(account.getServer().toString())) {
 258				socket = new Socket();
 259				try {
 260					socket.connect(new InetSocketAddress(account.getServer().toString(), 5222), Config.SOCKET_TIMEOUT * 1000);
 261				} catch (IOException e) {
 262					throw new UnknownHostException();
 263				}
 264				startXmpp();
 265			} else {
 266				final Bundle result = DNSHelper.getSRVRecord(account.getServer(), mXmppConnectionService);
 267				final ArrayList<Parcelable>values = result.getParcelableArrayList("values");
 268				for(Iterator<Parcelable> iterator = values.iterator(); iterator.hasNext();) {
 269					final Bundle namePort = (Bundle) iterator.next();
 270					try {
 271						String srvRecordServer;
 272						try {
 273							srvRecordServer = IDN.toASCII(namePort.getString("name"));
 274						} catch (final IllegalArgumentException e) {
 275							// TODO: Handle me?`
 276							srvRecordServer = "";
 277						}
 278						final int srvRecordPort = namePort.getInt("port");
 279						final String srvIpServer = namePort.getString("ip");
 280						// if tls is true, encryption is implied and must not be started
 281						features.encryptionEnabled = namePort.getBoolean("tls");
 282						final InetSocketAddress addr;
 283						if (srvIpServer != null) {
 284							addr = new InetSocketAddress(srvIpServer, srvRecordPort);
 285							Log.d(Config.LOGTAG, account.getJid().toBareJid().toString()
 286									+ ": using values from dns " + srvRecordServer
 287									+ "[" + srvIpServer + "]:" + srvRecordPort + " tls: " + features.encryptionEnabled);
 288						} else {
 289							addr = new InetSocketAddress(srvRecordServer, srvRecordPort);
 290							Log.d(Config.LOGTAG, account.getJid().toBareJid().toString()
 291									+ ": using values from dns "
 292									+ srvRecordServer + ":" + srvRecordPort + " tls: " + features.encryptionEnabled);
 293						}
 294
 295						if (!features.encryptionEnabled) {
 296							socket = new Socket();
 297							socket.connect(addr, Config.SOCKET_TIMEOUT * 1000);
 298						} else {
 299							final TlsFactoryVerifier tlsFactoryVerifier = getTlsFactoryVerifier();
 300							socket = tlsFactoryVerifier.factory.createSocket();
 301
 302							if (socket == null) {
 303								throw new IOException("could not initialize ssl socket");
 304							}
 305
 306							SSLSocketHelper.setSecurity((SSLSocket) socket);
 307							SSLSocketHelper.setSNIHost(tlsFactoryVerifier.factory, (SSLSocket) socket, account.getServer().getDomainpart());
 308							SSLSocketHelper.setAlpnProtocol(tlsFactoryVerifier.factory, (SSLSocket) socket, "xmpp-client");
 309
 310							socket.connect(addr, Config.SOCKET_TIMEOUT * 1000);
 311
 312							if (!tlsFactoryVerifier.verifier.verify(account.getServer().getDomainpart(), ((SSLSocket) socket).getSession())) {
 313								Log.d(Config.LOGTAG, account.getJid().toBareJid() + ": TLS certificate verification failed");
 314								throw new SecurityException();
 315							}
 316						}
 317
 318						if (startXmpp())
 319							break; // successfully connected to server that speaks xmpp
 320					} catch(final SecurityException e) {
 321						throw e;
 322					} catch (final Throwable e) {
 323						Log.d(Config.LOGTAG, account.getJid().toBareJid().toString() + ": " + e.getMessage() +"("+e.getClass().getName()+")");
 324						if (!iterator.hasNext()) {
 325							throw new UnknownHostException();
 326						}
 327					}
 328				}
 329			}
 330			processStream();
 331		} catch (final IncompatibleServerException e) {
 332			this.changeStatus(Account.State.INCOMPATIBLE_SERVER);
 333		} catch (final SecurityException e) {
 334			this.changeStatus(Account.State.SECURITY_ERROR);
 335		} catch (final UnauthorizedException e) {
 336			this.changeStatus(Account.State.UNAUTHORIZED);
 337		} catch (final UnknownHostException | ConnectException e) {
 338			this.changeStatus(Account.State.SERVER_NOT_FOUND);
 339		} catch (final SocksSocketFactory.SocksProxyNotFoundException e) {
 340			this.changeStatus(Account.State.TOR_NOT_AVAILABLE);
 341		} catch (final IOException | XmlPullParserException | NoSuchAlgorithmException e) {
 342			Log.d(Config.LOGTAG, account.getJid().toBareJid().toString() + ": " + e.getMessage());
 343			this.changeStatus(Account.State.OFFLINE);
 344			this.attempt--; //don't count attempt when reconnecting instantly anyway
 345		} finally {
 346			if (socket != null) {
 347				try {
 348					socket.close();
 349				} catch (IOException e) {
 350
 351				}
 352			}
 353			if (wakeLock.isHeld()) {
 354				try {
 355					wakeLock.release();
 356				} catch (final RuntimeException ignored) {
 357				}
 358			}
 359		}
 360	}
 361
 362	/**
 363	 * Starts xmpp protocol, call after connecting to socket
 364	 * @return true if server returns with valid xmpp, false otherwise
 365	 * @throws IOException Unknown tag on connect
 366	 * @throws XmlPullParserException Bad Xml
 367	 * @throws NoSuchAlgorithmException Other error
 368     */
 369	private boolean startXmpp() throws IOException, XmlPullParserException, NoSuchAlgorithmException {
 370		tagWriter.setOutputStream(socket.getOutputStream());
 371		tagReader.setInputStream(socket.getInputStream());
 372		tagWriter.beginDocument();
 373		sendStartStream();
 374		Tag nextTag;
 375		while ((nextTag = tagReader.readTag()) != null) {
 376			if (nextTag.isStart("stream")) {
 377				return true;
 378			} else {
 379				throw new IOException("unknown tag on connect");
 380			}
 381		}
 382		if (socket.isConnected()) {
 383			socket.close();
 384		}
 385		return false;
 386	}
 387
 388	private static class TlsFactoryVerifier {
 389		private final SSLSocketFactory factory;
 390		private final HostnameVerifier verifier;
 391
 392		public TlsFactoryVerifier(final SSLSocketFactory factory, final HostnameVerifier verifier) throws IOException {
 393			this.factory = factory;
 394			this.verifier = verifier;
 395			if (factory == null || verifier == null) {
 396				throw new IOException("could not setup ssl");
 397			}
 398		}
 399	}
 400
 401	private TlsFactoryVerifier getTlsFactoryVerifier() throws NoSuchAlgorithmException, KeyManagementException, IOException {
 402		final SSLContext sc = SSLContext.getInstance("TLS");
 403		MemorizingTrustManager trustManager = this.mXmppConnectionService.getMemorizingTrustManager();
 404		KeyManager[] keyManager;
 405		if (account.getPrivateKeyAlias() != null && account.getPassword().isEmpty()) {
 406			keyManager = new KeyManager[]{mKeyManager};
 407		} else {
 408			keyManager = null;
 409		}
 410		sc.init(keyManager, new X509TrustManager[]{mInteractive ? trustManager : trustManager.getNonInteractive()}, mXmppConnectionService.getRNG());
 411		final SSLSocketFactory factory = sc.getSocketFactory();
 412		final HostnameVerifier verifier;
 413		if (mInteractive) {
 414			verifier = trustManager.wrapHostnameVerifier(new XmppDomainVerifier());
 415		} else {
 416			verifier = trustManager.wrapHostnameVerifierNonInteractive(new XmppDomainVerifier());
 417		}
 418
 419		return new TlsFactoryVerifier(factory, verifier);
 420	}
 421
 422	@Override
 423	public void run() {
 424		try {
 425			if (socket != null) {
 426				socket.close();
 427			}
 428		} catch (final IOException ignored) {
 429
 430		}
 431		connect();
 432	}
 433
 434	private void processStream() throws XmlPullParserException, IOException, NoSuchAlgorithmException {
 435		Tag nextTag = tagReader.readTag();
 436		while (nextTag != null && !nextTag.isEnd("stream")) {
 437			if (nextTag.isStart("error")) {
 438				processStreamError(nextTag);
 439			} else if (nextTag.isStart("features")) {
 440				processStreamFeatures(nextTag);
 441			} else if (nextTag.isStart("proceed")) {
 442				switchOverToTls(nextTag);
 443			} else if (nextTag.isStart("success")) {
 444				final String challenge = tagReader.readElement(nextTag).getContent();
 445				try {
 446					saslMechanism.getResponse(challenge);
 447				} catch (final SaslMechanism.AuthenticationException e) {
 448					disconnect(true);
 449					Log.e(Config.LOGTAG, String.valueOf(e));
 450				}
 451				Log.d(Config.LOGTAG, account.getJid().toBareJid().toString() + ": logged in");
 452				account.setKey(Account.PINNED_MECHANISM_KEY,
 453						String.valueOf(saslMechanism.getPriority()));
 454				tagReader.reset();
 455				sendStartStream();
 456				final Tag tag = tagReader.readTag();
 457				if (tag != null && tag.isStart("stream")) {
 458					processStream();
 459				} else {
 460					throw new IOException("server didn't restart stream after successful auth");
 461				}
 462				break;
 463			} else if (nextTag.isStart("failure")) {
 464				throw new UnauthorizedException();
 465			} else if (nextTag.isStart("challenge")) {
 466				final String challenge = tagReader.readElement(nextTag).getContent();
 467				final Element response = new Element("response");
 468				response.setAttribute("xmlns",
 469						"urn:ietf:params:xml:ns:xmpp-sasl");
 470				try {
 471					response.setContent(saslMechanism.getResponse(challenge));
 472				} catch (final SaslMechanism.AuthenticationException e) {
 473					// TODO: Send auth abort tag.
 474					Log.e(Config.LOGTAG, e.toString());
 475				}
 476				tagWriter.writeElement(response);
 477			} else if (nextTag.isStart("enabled")) {
 478				final Element enabled = tagReader.readElement(nextTag);
 479				if ("true".equals(enabled.getAttribute("resume"))) {
 480					this.streamId = enabled.getAttribute("id");
 481					Log.d(Config.LOGTAG, account.getJid().toBareJid().toString()
 482							+ ": stream managment(" + smVersion
 483							+ ") enabled (resumable)");
 484				} else {
 485					Log.d(Config.LOGTAG, account.getJid().toBareJid().toString()
 486							+ ": stream management(" + smVersion + ") enabled");
 487				}
 488				this.stanzasReceived = 0;
 489				final RequestPacket r = new RequestPacket(smVersion);
 490				tagWriter.writeStanzaAsync(r);
 491			} else if (nextTag.isStart("resumed")) {
 492				lastPacketReceived = SystemClock.elapsedRealtime();
 493				final Element resumed = tagReader.readElement(nextTag);
 494				final String h = resumed.getAttribute("h");
 495				try {
 496					final int serverCount = Integer.parseInt(h);
 497					if (serverCount != stanzasSent) {
 498						Log.d(Config.LOGTAG, account.getJid().toBareJid().toString()
 499								+ ": session resumed with lost packages");
 500						stanzasSent = serverCount;
 501					} else {
 502						Log.d(Config.LOGTAG, account.getJid().toBareJid().toString() + ": session resumed");
 503					}
 504					acknowledgeStanzaUpTo(serverCount);
 505					ArrayList<AbstractAcknowledgeableStanza> failedStanzas = new ArrayList<>();
 506					for(int i = 0; i < this.mStanzaQueue.size(); ++i) {
 507						failedStanzas.add(mStanzaQueue.valueAt(i));
 508					}
 509					mStanzaQueue.clear();
 510					Log.d(Config.LOGTAG,"resending "+failedStanzas.size()+" stanzas");
 511					for(AbstractAcknowledgeableStanza packet : failedStanzas) {
 512						if (packet instanceof MessagePacket) {
 513							MessagePacket message = (MessagePacket) packet;
 514							mXmppConnectionService.markMessage(account,
 515									message.getTo().toBareJid(),
 516									message.getId(),
 517									Message.STATUS_UNSEND);
 518						}
 519						sendPacket(packet);
 520					}
 521				} catch (final NumberFormatException ignored) {
 522				}
 523				Log.d(Config.LOGTAG, account.getJid().toBareJid()+ ": online with resource " + account.getResource());
 524				changeStatus(Account.State.ONLINE);
 525			} else if (nextTag.isStart("r")) {
 526				tagReader.readElement(nextTag);
 527				if (Config.EXTENDED_SM_LOGGING) {
 528					Log.d(Config.LOGTAG, account.getJid().toBareJid() + ": acknowledging stanza #" + this.stanzasReceived);
 529				}
 530				final AckPacket ack = new AckPacket(this.stanzasReceived, smVersion);
 531				tagWriter.writeStanzaAsync(ack);
 532			} else if (nextTag.isStart("a")) {
 533				final Element ack = tagReader.readElement(nextTag);
 534				lastPacketReceived = SystemClock.elapsedRealtime();
 535				try {
 536					final int serverSequence = Integer.parseInt(ack.getAttribute("h"));
 537					acknowledgeStanzaUpTo(serverSequence);
 538				} catch (NumberFormatException e) {
 539					Log.d(Config.LOGTAG,account.getJid().toBareJid()+": server send ack without sequence number");
 540				}
 541			} else if (nextTag.isStart("failed")) {
 542				tagReader.readElement(nextTag);
 543				Log.d(Config.LOGTAG, account.getJid().toBareJid().toString() + ": resumption failed");
 544				streamId = null;
 545				if (account.getStatus() != Account.State.ONLINE) {
 546					sendBindRequest();
 547				}
 548			} else if (nextTag.isStart("iq")) {
 549				processIq(nextTag);
 550			} else if (nextTag.isStart("message")) {
 551				processMessage(nextTag);
 552			} else if (nextTag.isStart("presence")) {
 553				processPresence(nextTag);
 554			}
 555			nextTag = tagReader.readTag();
 556		}
 557		throw new IOException("reached end of stream. last tag was "+nextTag);
 558	}
 559
 560	private void acknowledgeStanzaUpTo(int serverCount) {
 561		for (int i = 0; i < mStanzaQueue.size(); ++i) {
 562			if (serverCount >= mStanzaQueue.keyAt(i)) {
 563				if (Config.EXTENDED_SM_LOGGING) {
 564					Log.d(Config.LOGTAG, account.getJid().toBareJid() + ": server acknowledged stanza #" + mStanzaQueue.keyAt(i));
 565				}
 566				AbstractAcknowledgeableStanza stanza = mStanzaQueue.valueAt(i);
 567				if (stanza instanceof MessagePacket && acknowledgedListener != null) {
 568					MessagePacket packet = (MessagePacket) stanza;
 569					acknowledgedListener.onMessageAcknowledged(account, packet.getId());
 570				}
 571				mStanzaQueue.removeAt(i);
 572				i--;
 573			}
 574		}
 575	}
 576
 577	private Element processPacket(final Tag currentTag, final int packetType)
 578		throws XmlPullParserException, IOException {
 579		Element element;
 580		switch (packetType) {
 581			case PACKET_IQ:
 582				element = new IqPacket();
 583				break;
 584			case PACKET_MESSAGE:
 585				element = new MessagePacket();
 586				break;
 587			case PACKET_PRESENCE:
 588				element = new PresencePacket();
 589				break;
 590			default:
 591				return null;
 592		}
 593		element.setAttributes(currentTag.getAttributes());
 594		Tag nextTag = tagReader.readTag();
 595		if (nextTag == null) {
 596			throw new IOException("interrupted mid tag");
 597		}
 598		while (!nextTag.isEnd(element.getName())) {
 599			if (!nextTag.isNo()) {
 600				final Element child = tagReader.readElement(nextTag);
 601				final String type = currentTag.getAttribute("type");
 602				if (packetType == PACKET_IQ
 603						&& "jingle".equals(child.getName())
 604						&& ("set".equalsIgnoreCase(type) || "get"
 605							.equalsIgnoreCase(type))) {
 606					element = new JinglePacket();
 607					element.setAttributes(currentTag.getAttributes());
 608							}
 609				element.addChild(child);
 610			}
 611			nextTag = tagReader.readTag();
 612			if (nextTag == null) {
 613				throw new IOException("interrupted mid tag");
 614			}
 615		}
 616		if (stanzasReceived == Integer.MAX_VALUE) {
 617			resetStreamId();
 618			throw new IOException("time to restart the session. cant handle >2 billion pcks");
 619		}
 620		++stanzasReceived;
 621		lastPacketReceived = SystemClock.elapsedRealtime();
 622		return element;
 623	}
 624
 625	private void processIq(final Tag currentTag) throws XmlPullParserException, IOException {
 626		final IqPacket packet = (IqPacket) processPacket(currentTag, PACKET_IQ);
 627
 628		if (packet.getId() == null) {
 629			return; // an iq packet without id is definitely invalid
 630		}
 631
 632		if (packet instanceof JinglePacket) {
 633			if (this.jingleListener != null) {
 634				this.jingleListener.onJinglePacketReceived(account,(JinglePacket) packet);
 635			}
 636		} else {
 637			OnIqPacketReceived callback = null;
 638			synchronized (this.packetCallbacks) {
 639				if (packetCallbacks.containsKey(packet.getId())) {
 640					final Pair<IqPacket, OnIqPacketReceived> packetCallbackDuple = packetCallbacks.get(packet.getId());
 641					// Packets to the server should have responses from the server
 642					if (packetCallbackDuple.first.toServer(account)) {
 643						if (packet.fromServer(account) || mServerIdentity == Identity.FACEBOOK) {
 644							callback = packetCallbackDuple.second;
 645							packetCallbacks.remove(packet.getId());
 646						} else {
 647							Log.e(Config.LOGTAG, account.getJid().toBareJid().toString() + ": ignoring spoofed iq packet");
 648						}
 649					} else {
 650						if (packet.getFrom().equals(packetCallbackDuple.first.getTo())) {
 651							callback = packetCallbackDuple.second;
 652							packetCallbacks.remove(packet.getId());
 653						} else {
 654							Log.e(Config.LOGTAG, account.getJid().toBareJid().toString() + ": ignoring spoofed iq packet");
 655						}
 656					}
 657				} else if (packet.getType() == IqPacket.TYPE.GET || packet.getType() == IqPacket.TYPE.SET) {
 658					callback = this.unregisteredIqListener;
 659				}
 660			}
 661			if (callback != null) {
 662				callback.onIqPacketReceived(account,packet);
 663			}
 664		}
 665	}
 666
 667	private void processMessage(final Tag currentTag) throws XmlPullParserException, IOException {
 668		final MessagePacket packet = (MessagePacket) processPacket(currentTag,PACKET_MESSAGE);
 669		this.messageListener.onMessagePacketReceived(account, packet);
 670	}
 671
 672	private void processPresence(final Tag currentTag) throws XmlPullParserException, IOException {
 673		PresencePacket packet = (PresencePacket) processPacket(currentTag, PACKET_PRESENCE);
 674		this.presenceListener.onPresencePacketReceived(account, packet);
 675	}
 676
 677	private void sendStartTLS() throws IOException {
 678		final Tag startTLS = Tag.empty("starttls");
 679		startTLS.setAttribute("xmlns", "urn:ietf:params:xml:ns:xmpp-tls");
 680		tagWriter.writeTag(startTLS);
 681	}
 682
 683
 684
 685	private void switchOverToTls(final Tag currentTag) throws XmlPullParserException, IOException {
 686		tagReader.readTag();
 687		try {
 688			final TlsFactoryVerifier tlsFactoryVerifier = getTlsFactoryVerifier();
 689			final InetAddress address = socket == null ? null : socket.getInetAddress();
 690
 691			if (address == null) {
 692				throw new IOException("could not setup ssl");
 693			}
 694
 695			final SSLSocket sslSocket = (SSLSocket) tlsFactoryVerifier.factory.createSocket(socket, address.getHostAddress(), socket.getPort(), true);
 696
 697			if (sslSocket == null) {
 698				throw new IOException("could not initialize ssl socket");
 699			}
 700
 701			SSLSocketHelper.setSecurity(sslSocket);
 702
 703			if (!tlsFactoryVerifier.verifier.verify(account.getServer().getDomainpart(), sslSocket.getSession())) {
 704				Log.d(Config.LOGTAG,account.getJid().toBareJid()+": TLS certificate verification failed");
 705				throw new SecurityException();
 706			}
 707			tagReader.setInputStream(sslSocket.getInputStream());
 708			tagWriter.setOutputStream(sslSocket.getOutputStream());
 709			sendStartStream();
 710			Log.d(Config.LOGTAG, account.getJid().toBareJid()+ ": TLS connection established");
 711			features.encryptionEnabled = true;
 712			final Tag tag = tagReader.readTag();
 713			if (tag != null && tag.isStart("stream")) {
 714				processStream();
 715			} else {
 716				throw new IOException("server didn't restart stream after STARTTLS");
 717			}
 718			sslSocket.close();
 719		} catch (final NoSuchAlgorithmException | KeyManagementException e1) {
 720			Log.d(Config.LOGTAG, account.getJid().toBareJid() + ": TLS certificate verification failed");
 721			throw new SecurityException();
 722		}
 723	}
 724
 725	private void processStreamFeatures(final Tag currentTag)
 726		throws XmlPullParserException, IOException {
 727		this.streamFeatures = tagReader.readElement(currentTag);
 728		if (this.streamFeatures.hasChild("starttls") && !features.encryptionEnabled) {
 729			sendStartTLS();
 730		} else if (this.streamFeatures.hasChild("register") && account.isOptionSet(Account.OPTION_REGISTER)) {
 731			if (features.encryptionEnabled || Config.ALLOW_NON_TLS_CONNECTIONS) {
 732				sendRegistryRequest();
 733			} else {
 734				throw new IncompatibleServerException();
 735			}
 736		} else if (!this.streamFeatures.hasChild("register")
 737				&& account.isOptionSet(Account.OPTION_REGISTER)) {
 738			changeStatus(Account.State.REGISTRATION_NOT_SUPPORTED);
 739			disconnect(true);
 740		} else if (this.streamFeatures.hasChild("mechanisms")
 741				&& shouldAuthenticate
 742				&& (features.encryptionEnabled || Config.ALLOW_NON_TLS_CONNECTIONS)) {
 743			final List<String> mechanisms = extractMechanisms(streamFeatures
 744					.findChild("mechanisms"));
 745			final Element auth = new Element("auth");
 746			auth.setAttribute("xmlns", "urn:ietf:params:xml:ns:xmpp-sasl");
 747			if (mechanisms.contains("EXTERNAL") && account.getPrivateKeyAlias() != null) {
 748				saslMechanism = new External(tagWriter, account, mXmppConnectionService.getRNG());
 749			} else if (mechanisms.contains("SCRAM-SHA-1")) {
 750				saslMechanism = new ScramSha1(tagWriter, account, mXmppConnectionService.getRNG());
 751			} else if (mechanisms.contains("PLAIN")) {
 752				saslMechanism = new Plain(tagWriter, account);
 753			} else if (mechanisms.contains("DIGEST-MD5")) {
 754				saslMechanism = new DigestMd5(tagWriter, account, mXmppConnectionService.getRNG());
 755			}
 756			if (saslMechanism != null) {
 757				final JSONObject keys = account.getKeys();
 758				try {
 759					if (keys.has(Account.PINNED_MECHANISM_KEY) &&
 760							keys.getInt(Account.PINNED_MECHANISM_KEY) > saslMechanism.getPriority()) {
 761						Log.e(Config.LOGTAG, "Auth failed. Authentication mechanism " + saslMechanism.getMechanism() +
 762								" has lower priority (" + String.valueOf(saslMechanism.getPriority()) +
 763								") than pinned priority (" + keys.getInt(Account.PINNED_MECHANISM_KEY) +
 764								"). Possible downgrade attack?");
 765						throw new SecurityException();
 766					}
 767				} catch (final JSONException e) {
 768					Log.d(Config.LOGTAG, "Parse error while checking pinned auth mechanism");
 769				}
 770				Log.d(Config.LOGTAG, account.getJid().toString() + ": Authenticating with " + saslMechanism.getMechanism());
 771				auth.setAttribute("mechanism", saslMechanism.getMechanism());
 772				if (!saslMechanism.getClientFirstMessage().isEmpty()) {
 773					auth.setContent(saslMechanism.getClientFirstMessage());
 774				}
 775				tagWriter.writeElement(auth);
 776			} else {
 777				throw new IncompatibleServerException();
 778			}
 779		} else if (this.streamFeatures.hasChild("sm", "urn:xmpp:sm:" + smVersion) && streamId != null) {
 780			if (Config.EXTENDED_SM_LOGGING) {
 781				Log.d(Config.LOGTAG,account.getJid().toBareJid()+": resuming after stanza #"+stanzasReceived);
 782			}
 783			final ResumePacket resume = new ResumePacket(this.streamId, stanzasReceived, smVersion);
 784			this.tagWriter.writeStanzaAsync(resume);
 785		} else if (needsBinding) {
 786			if (this.streamFeatures.hasChild("bind")) {
 787				sendBindRequest();
 788			} else {
 789				throw new IncompatibleServerException();
 790			}
 791		}
 792	}
 793
 794	private List<String> extractMechanisms(final Element stream) {
 795		final ArrayList<String> mechanisms = new ArrayList<>(stream
 796				.getChildren().size());
 797		for (final Element child : stream.getChildren()) {
 798			mechanisms.add(child.getContent());
 799		}
 800		return mechanisms;
 801	}
 802
 803	public void sendCaptchaRegistryRequest(String id, Data data) {
 804		if (data == null) {
 805			setAccountCreationFailed("");
 806		} else {
 807			IqPacket request = getIqGenerator().generateCreateAccountWithCaptcha(account, id, data);
 808			sendIqPacket(request, createPacketReceiveHandler());
 809		}
 810	}
 811
 812	private void sendRegistryRequest() {
 813		final IqPacket register = new IqPacket(IqPacket.TYPE.GET);
 814		register.query("jabber:iq:register");
 815		register.setTo(account.getServer());
 816		sendIqPacket(register, new OnIqPacketReceived() {
 817
 818			@Override
 819			public void onIqPacketReceived(final Account account, final IqPacket packet) {
 820				boolean failed = false;
 821				if (packet.getType() == IqPacket.TYPE.RESULT
 822						&& packet.query().hasChild("username")
 823						&& (packet.query().hasChild("password"))) {
 824					final IqPacket register = new IqPacket(IqPacket.TYPE.SET);
 825					final Element username = new Element("username").setContent(account.getUsername());
 826					final Element password = new Element("password").setContent(account.getPassword());
 827					register.query("jabber:iq:register").addChild(username);
 828					register.query().addChild(password);
 829					sendIqPacket(register, createPacketReceiveHandler());
 830				} else if (packet.getType() == IqPacket.TYPE.RESULT
 831						&& (packet.query().hasChild("x", "jabber:x:data"))) {
 832					final Data data = Data.parse(packet.query().findChild("x", "jabber:x:data"));
 833					final Element blob = packet.query().findChild("data", "urn:xmpp:bob");
 834					final String id = packet.getId();
 835
 836					Bitmap captcha = null;
 837					if (blob != null) {
 838						try {
 839							final String base64Blob = blob.getContent();
 840							final byte[] strBlob = Base64.decode(base64Blob, Base64.DEFAULT);
 841							InputStream stream = new ByteArrayInputStream(strBlob);
 842							captcha = BitmapFactory.decodeStream(stream);
 843						} catch (Exception e) {
 844							//ignored
 845						}
 846					} else {
 847						try {
 848							Field url = data.getFieldByName("url");
 849							String urlString = url.findChildContent("value");
 850							URL uri = new URL(urlString);
 851							captcha = BitmapFactory.decodeStream(uri.openConnection().getInputStream());
 852						} catch (IOException e) {
 853							Log.e(Config.LOGTAG, e.toString());
 854						}
 855					}
 856
 857					if (captcha != null) {
 858						failed = !mXmppConnectionService.displayCaptchaRequest(account, id, data, captcha);
 859					}
 860				} else {
 861					failed = true;
 862				}
 863
 864				if (failed) {
 865					final Element instructions = packet.query().findChild("instructions");
 866					setAccountCreationFailed((instructions != null) ? instructions.getContent() : "");
 867				}
 868			}
 869		});
 870	}
 871
 872	private void setAccountCreationFailed(String instructions) {
 873		changeStatus(Account.State.REGISTRATION_FAILED);
 874		disconnect(true);
 875		Log.d(Config.LOGTAG, account.getJid().toBareJid()
 876				+ ": could not register. instructions are"
 877				+ instructions);
 878	}
 879
 880	public void resetEverything() {
 881		resetStreamId();
 882		clearIqCallbacks();
 883		mStanzaQueue.clear();
 884		synchronized (this.disco) {
 885			disco.clear();
 886		}
 887	}
 888
 889	private void sendBindRequest() {
 890		while(!mXmppConnectionService.areMessagesInitialized() && socket != null && !socket.isClosed()) {
 891			try {
 892				Thread.sleep(500);
 893			} catch (final InterruptedException ignored) {
 894			}
 895		}
 896		needsBinding = false;
 897		clearIqCallbacks();
 898		final IqPacket iq = new IqPacket(IqPacket.TYPE.SET);
 899		iq.addChild("bind", "urn:ietf:params:xml:ns:xmpp-bind")
 900				.addChild("resource").setContent(account.getResource());
 901		this.sendUnmodifiedIqPacket(iq, new OnIqPacketReceived() {
 902			@Override
 903			public void onIqPacketReceived(final Account account, final IqPacket packet) {
 904				if (packet.getType() == IqPacket.TYPE.TIMEOUT) {
 905					return;
 906				}
 907				final Element bind = packet.findChild("bind");
 908				if (bind != null && packet.getType() == IqPacket.TYPE.RESULT) {
 909					final Element jid = bind.findChild("jid");
 910					if (jid != null && jid.getContent() != null) {
 911						try {
 912							account.setResource(Jid.fromString(jid.getContent()).getResourcepart());
 913						} catch (final InvalidJidException e) {
 914							// TODO: Handle the case where an external JID is technically invalid?
 915						}
 916						if (streamFeatures.hasChild("session")) {
 917							sendStartSession();
 918						} else {
 919							sendPostBindInitialization();
 920						}
 921					} else {
 922						Log.d(Config.LOGTAG, account.getJid() + ": disconnecting because of bind failure");
 923						disconnect(true);
 924					}
 925				} else {
 926					Log.d(Config.LOGTAG, account.getJid() + ": disconnecting because of bind failure");
 927					disconnect(true);
 928				}
 929			}
 930		});
 931	}
 932
 933	private void clearIqCallbacks() {
 934		final IqPacket failurePacket = new IqPacket(IqPacket.TYPE.TIMEOUT);
 935		final ArrayList<OnIqPacketReceived> callbacks = new ArrayList<>();
 936		synchronized (this.packetCallbacks) {
 937			if (this.packetCallbacks.size() == 0) {
 938				return;
 939			}
 940			Log.d(Config.LOGTAG, account.getJid().toBareJid() + ": clearing "+this.packetCallbacks.size()+" iq callbacks");
 941			final Iterator<Pair<IqPacket, OnIqPacketReceived>> iterator = this.packetCallbacks.values().iterator();
 942			while (iterator.hasNext()) {
 943				Pair<IqPacket, OnIqPacketReceived> entry = iterator.next();
 944				callbacks.add(entry.second);
 945				iterator.remove();
 946			}
 947		}
 948		for(OnIqPacketReceived callback : callbacks) {
 949			callback.onIqPacketReceived(account,failurePacket);
 950		}
 951		Log.d(Config.LOGTAG, account.getJid().toBareJid() + ": done clearing iq callbacks. " + this.packetCallbacks.size() + " left");
 952	}
 953
 954	public void sendDiscoTimeout() {
 955		final IqPacket failurePacket = new IqPacket(IqPacket.TYPE.ERROR); //don't use timeout
 956		final ArrayList<OnIqPacketReceived> callbacks = new ArrayList<>();
 957		synchronized (this.mPendingServiceDiscoveriesIds) {
 958			for(String id : mPendingServiceDiscoveriesIds) {
 959				synchronized (this.packetCallbacks) {
 960					Pair<IqPacket, OnIqPacketReceived> pair = this.packetCallbacks.remove(id);
 961					if (pair != null) {
 962						callbacks.add(pair.second);
 963					}
 964				}
 965			}
 966			this.mPendingServiceDiscoveriesIds.clear();
 967		}
 968		if (callbacks.size() > 0) {
 969			Log.d(Config.LOGTAG,account.getJid().toBareJid()+": sending disco timeout");
 970			resetStreamId(); //we don't want to live with this for ever
 971		}
 972		for(OnIqPacketReceived callback : callbacks) {
 973			callback.onIqPacketReceived(account,failurePacket);
 974		}
 975	}
 976
 977	private void sendStartSession() {
 978		final IqPacket startSession = new IqPacket(IqPacket.TYPE.SET);
 979		startSession.addChild("session", "urn:ietf:params:xml:ns:xmpp-session");
 980		this.sendUnmodifiedIqPacket(startSession, new OnIqPacketReceived() {
 981			@Override
 982			public void onIqPacketReceived(Account account, IqPacket packet) {
 983				if (packet.getType() == IqPacket.TYPE.RESULT) {
 984					sendPostBindInitialization();
 985				} else if (packet.getType() != IqPacket.TYPE.TIMEOUT) {
 986					Log.d(Config.LOGTAG, account.getJid().toBareJid() + ": could not init sessions");
 987					disconnect(true);
 988				}
 989			}
 990		});
 991	}
 992
 993	private void sendPostBindInitialization() {
 994		smVersion = 0;
 995		if (streamFeatures.hasChild("sm", "urn:xmpp:sm:3")) {
 996			smVersion = 3;
 997		} else if (streamFeatures.hasChild("sm", "urn:xmpp:sm:2")) {
 998			smVersion = 2;
 999		}
1000		if (smVersion != 0) {
1001			final EnablePacket enable = new EnablePacket(smVersion);
1002			tagWriter.writeStanzaAsync(enable);
1003			stanzasSent = 0;
1004			mStanzaQueue.clear();
1005		}
1006		features.carbonsEnabled = false;
1007		features.blockListRequested = false;
1008		synchronized (this.disco) {
1009			this.disco.clear();
1010		}
1011		mPendingServiceDiscoveries = mServerIdentity == Identity.NIMBUZZ ? 1 : 0;
1012		lastDiscoStarted = SystemClock.elapsedRealtime();
1013		Log.d(Config.LOGTAG, account.getJid().toBareJid() + ": starting service discovery");
1014		mXmppConnectionService.scheduleWakeUpCall(Config.CONNECT_DISCO_TIMEOUT, account.getUuid().hashCode());
1015		sendServiceDiscoveryItems(account.getServer());
1016		sendServiceDiscoveryInfo(account.getServer());
1017		sendServiceDiscoveryInfo(account.getJid().toBareJid());
1018		this.lastSessionStarted = SystemClock.elapsedRealtime();
1019	}
1020
1021	private void sendServiceDiscoveryInfo(final Jid jid) {
1022		if (mServerIdentity != Identity.NIMBUZZ) {
1023			mPendingServiceDiscoveries++;
1024		}
1025		final IqPacket iq = new IqPacket(IqPacket.TYPE.GET);
1026		iq.setTo(jid);
1027		iq.query("http://jabber.org/protocol/disco#info");
1028		String id = this.sendIqPacket(iq, new OnIqPacketReceived() {
1029
1030			@Override
1031			public void onIqPacketReceived(final Account account, final IqPacket packet) {
1032				if (packet.getType() == IqPacket.TYPE.RESULT) {
1033					boolean advancedStreamFeaturesLoaded;
1034					synchronized (XmppConnection.this.disco) {
1035						ServiceDiscoveryResult result = new ServiceDiscoveryResult(packet);
1036						for (final ServiceDiscoveryResult.Identity id : result.getIdentities()) {
1037							if (mServerIdentity == Identity.UNKNOWN && id.getType().equals("im") &&
1038							    id.getCategory().equals("server") && id.getName() != null &&
1039							    jid.equals(account.getServer())) {
1040									switch (id.getName()) {
1041										case "Prosody":
1042											mServerIdentity = Identity.PROSODY;
1043											break;
1044										case "ejabberd":
1045											mServerIdentity = Identity.EJABBERD;
1046											break;
1047										case "Slack-XMPP":
1048											mServerIdentity = Identity.SLACK;
1049											break;
1050									}
1051									Log.d(Config.LOGTAG, account.getJid().toBareJid() + ": server name: " + id.getName());
1052								}
1053						}
1054						disco.put(jid, result);
1055						advancedStreamFeaturesLoaded = disco.containsKey(account.getServer())
1056								&& disco.containsKey(account.getJid().toBareJid());
1057					}
1058					if (advancedStreamFeaturesLoaded && (jid.equals(account.getServer()) || jid.equals(account.getJid().toBareJid()))) {
1059						enableAdvancedStreamFeatures();
1060					}
1061				} else {
1062					Log.d(Config.LOGTAG, account.getJid().toBareJid() + ": could not query disco info for " + jid.toString());
1063				}
1064				if (packet.getType() != IqPacket.TYPE.TIMEOUT) {
1065					mPendingServiceDiscoveries--;
1066					if (mPendingServiceDiscoveries == 0) {
1067						Log.d(Config.LOGTAG,account.getJid().toBareJid()+": done with service discovery");
1068						Log.d(Config.LOGTAG, account.getJid().toBareJid() + ": online with resource " + account.getResource());
1069						changeStatus(Account.State.ONLINE);
1070						if (bindListener != null) {
1071							bindListener.onBind(account);
1072						}
1073					}
1074				}
1075			}
1076		});
1077		synchronized (this.mPendingServiceDiscoveriesIds) {
1078			this.mPendingServiceDiscoveriesIds.add(id);
1079		}
1080	}
1081
1082	private void enableAdvancedStreamFeatures() {
1083		if (getFeatures().carbons() && !features.carbonsEnabled) {
1084			sendEnableCarbons();
1085		}
1086		if (getFeatures().blocking() && !features.blockListRequested) {
1087			Log.d(Config.LOGTAG, account.getJid().toBareJid() + ": Requesting block list");
1088			this.sendIqPacket(getIqGenerator().generateGetBlockList(), mXmppConnectionService.getIqParser());
1089		}
1090		for (final OnAdvancedStreamFeaturesLoaded listener : advancedStreamFeaturesLoadedListeners) {
1091			listener.onAdvancedStreamFeaturesAvailable(account);
1092		}
1093	}
1094
1095	private void sendServiceDiscoveryItems(final Jid server) {
1096		final IqPacket iq = new IqPacket(IqPacket.TYPE.GET);
1097		iq.setTo(server.toDomainJid());
1098		iq.query("http://jabber.org/protocol/disco#items");
1099		this.sendIqPacket(iq, new OnIqPacketReceived() {
1100
1101			@Override
1102			public void onIqPacketReceived(final Account account, final IqPacket packet) {
1103				if (packet.getType() == IqPacket.TYPE.RESULT) {
1104					final List<Element> elements = packet.query().getChildren();
1105					for (final Element element : elements) {
1106						if (element.getName().equals("item")) {
1107							final Jid jid = element.getAttributeAsJid("jid");
1108							if (jid != null && !jid.equals(account.getServer())) {
1109								sendServiceDiscoveryInfo(jid);
1110							}
1111						}
1112					}
1113				} else {
1114					Log.d(Config.LOGTAG, account.getJid().toBareJid() + ": could not query disco items of " + server);
1115				}
1116			}
1117		});
1118	}
1119
1120	private void sendEnableCarbons() {
1121		final IqPacket iq = new IqPacket(IqPacket.TYPE.SET);
1122		iq.addChild("enable", "urn:xmpp:carbons:2");
1123		this.sendIqPacket(iq, new OnIqPacketReceived() {
1124
1125			@Override
1126			public void onIqPacketReceived(final Account account, final IqPacket packet) {
1127				if (!packet.hasChild("error")) {
1128					Log.d(Config.LOGTAG, account.getJid().toBareJid()
1129							+ ": successfully enabled carbons");
1130					features.carbonsEnabled = true;
1131				} else {
1132					Log.d(Config.LOGTAG, account.getJid().toBareJid()
1133							+ ": error enableing carbons " + packet.toString());
1134				}
1135			}
1136		});
1137	}
1138
1139	private void processStreamError(final Tag currentTag)
1140		throws XmlPullParserException, IOException {
1141		final Element streamError = tagReader.readElement(currentTag);
1142		if (streamError != null && streamError.hasChild("conflict")) {
1143			final String resource = account.getResource().split("\\.")[0];
1144			account.setResource(resource + "." + nextRandomId());
1145			Log.d(Config.LOGTAG,
1146					account.getJid().toBareJid() + ": switching resource due to conflict ("
1147					+ account.getResource() + ")");
1148		} else if (streamError != null) {
1149			Log.d(Config.LOGTAG,account.getJid().toBareJid()+": stream error "+streamError.toString());
1150		}
1151	}
1152
1153	private void sendStartStream() throws IOException {
1154		final Tag stream = Tag.start("stream:stream");
1155		stream.setAttribute("to", account.getServer().toString());
1156		stream.setAttribute("version", "1.0");
1157		stream.setAttribute("xml:lang", "en");
1158		stream.setAttribute("xmlns", "jabber:client");
1159		stream.setAttribute("xmlns:stream", "http://etherx.jabber.org/streams");
1160		tagWriter.writeTag(stream);
1161	}
1162
1163	private String nextRandomId() {
1164		return new BigInteger(50, mXmppConnectionService.getRNG()).toString(32);
1165	}
1166
1167	public String sendIqPacket(final IqPacket packet, final OnIqPacketReceived callback) {
1168		packet.setFrom(account.getJid());
1169		return this.sendUnmodifiedIqPacket(packet, callback);
1170	}
1171
1172	private synchronized String sendUnmodifiedIqPacket(final IqPacket packet, final OnIqPacketReceived callback) {
1173		if (packet.getId() == null) {
1174			final String id = nextRandomId();
1175			packet.setAttribute("id", id);
1176		}
1177		if (callback != null) {
1178			synchronized (this.packetCallbacks) {
1179				packetCallbacks.put(packet.getId(), new Pair<>(packet, callback));
1180			}
1181		}
1182		this.sendPacket(packet);
1183		return packet.getId();
1184	}
1185
1186	public void sendMessagePacket(final MessagePacket packet) {
1187		this.sendPacket(packet);
1188	}
1189
1190	public void sendPresencePacket(final PresencePacket packet) {
1191		this.sendPacket(packet);
1192	}
1193
1194	private synchronized void sendPacket(final AbstractStanza packet) {
1195		if (stanzasSent == Integer.MAX_VALUE) {
1196			resetStreamId();
1197			disconnect(true);
1198			return;
1199		}
1200		tagWriter.writeStanzaAsync(packet);
1201		if (packet instanceof AbstractAcknowledgeableStanza) {
1202			AbstractAcknowledgeableStanza stanza = (AbstractAcknowledgeableStanza) packet;
1203			++stanzasSent;
1204			this.mStanzaQueue.put(stanzasSent, stanza);
1205			if (stanza instanceof MessagePacket && stanza.getId() != null && getFeatures().sm()) {
1206				if (Config.EXTENDED_SM_LOGGING) {
1207					Log.d(Config.LOGTAG, account.getJid().toBareJid() + ": requesting ack for message stanza #" + stanzasSent);
1208				}
1209				tagWriter.writeStanzaAsync(new RequestPacket(this.smVersion));
1210			}
1211		}
1212	}
1213
1214	public void sendPing() {
1215		if (!r()) {
1216			final IqPacket iq = new IqPacket(IqPacket.TYPE.GET);
1217			iq.setFrom(account.getJid());
1218			iq.addChild("ping", "urn:xmpp:ping");
1219			this.sendIqPacket(iq, null);
1220		}
1221		this.lastPingSent = SystemClock.elapsedRealtime();
1222	}
1223
1224	public void setOnMessagePacketReceivedListener(
1225			final OnMessagePacketReceived listener) {
1226		this.messageListener = listener;
1227			}
1228
1229	public void setOnUnregisteredIqPacketReceivedListener(
1230			final OnIqPacketReceived listener) {
1231		this.unregisteredIqListener = listener;
1232			}
1233
1234	public void setOnPresencePacketReceivedListener(
1235			final OnPresencePacketReceived listener) {
1236		this.presenceListener = listener;
1237			}
1238
1239	public void setOnJinglePacketReceivedListener(
1240			final OnJinglePacketReceived listener) {
1241		this.jingleListener = listener;
1242			}
1243
1244	public void setOnStatusChangedListener(final OnStatusChanged listener) {
1245		this.statusListener = listener;
1246	}
1247
1248	public void setOnBindListener(final OnBindListener listener) {
1249		this.bindListener = listener;
1250	}
1251
1252	public void setOnMessageAcknowledgeListener(final OnMessageAcknowledged listener) {
1253		this.acknowledgedListener = listener;
1254	}
1255
1256	public void addOnAdvancedStreamFeaturesAvailableListener(final OnAdvancedStreamFeaturesLoaded listener) {
1257		if (!this.advancedStreamFeaturesLoadedListeners.contains(listener)) {
1258			this.advancedStreamFeaturesLoadedListeners.add(listener);
1259		}
1260	}
1261
1262	public void disconnect(final boolean force) {
1263		Log.d(Config.LOGTAG, account.getJid().toBareJid() + ": disconnecting force="+Boolean.valueOf(force));
1264		if (force) {
1265			try {
1266				socket.close();
1267			} catch(Exception e) {
1268				Log.d(Config.LOGTAG,account.getJid().toBareJid().toString()+": exception during force close ("+e.getMessage()+")");
1269			}
1270			return;
1271		} else {
1272			resetStreamId();
1273			if (tagWriter.isActive()) {
1274				tagWriter.finish();
1275				try {
1276					int i = 0;
1277					boolean warned = false;
1278					while (!tagWriter.finished() && socket.isConnected() && i <= 10) {
1279						if (!warned) {
1280							Log.d(Config.LOGTAG, account.getJid().toBareJid()+": waiting for tag writer to finish");
1281							warned = true;
1282						}
1283						Thread.sleep(200);
1284						i++;
1285					}
1286					if (warned) {
1287						Log.d(Config.LOGTAG,account.getJid().toBareJid()+": tag writer has finished");
1288					}
1289					Log.d(Config.LOGTAG,account.getJid().toBareJid()+": closing stream");
1290					tagWriter.writeTag(Tag.end("stream:stream"));
1291				} catch (final IOException e) {
1292					Log.d(Config.LOGTAG,account.getJid().toBareJid()+": io exception during disconnect ("+e.getMessage()+")");
1293				} catch (final InterruptedException e) {
1294					Log.d(Config.LOGTAG, "interrupted");
1295				}
1296			}
1297		}
1298	}
1299
1300	public void resetStreamId() {
1301		this.streamId = null;
1302	}
1303
1304	public List<Jid> findDiscoItemsByFeature(final String feature) {
1305		synchronized (this.disco) {
1306			final List<Jid> items = new ArrayList<>();
1307			for (final Entry<Jid, ServiceDiscoveryResult> cursor : this.disco.entrySet()) {
1308				if (cursor.getValue().getFeatures().contains(feature)) {
1309					items.add(cursor.getKey());
1310				}
1311			}
1312			return items;
1313		}
1314	}
1315
1316	public Jid findDiscoItemByFeature(final String feature) {
1317		final List<Jid> items = findDiscoItemsByFeature(feature);
1318		if (items.size() >= 1) {
1319			return items.get(0);
1320		}
1321		return null;
1322	}
1323
1324	public boolean r() {
1325		if (getFeatures().sm()) {
1326			this.tagWriter.writeStanzaAsync(new RequestPacket(smVersion));
1327			return true;
1328		} else {
1329			return false;
1330		}
1331	}
1332
1333	public String getMucServer() {
1334		synchronized (this.disco) {
1335			for (final Entry<Jid, ServiceDiscoveryResult> cursor : disco.entrySet()) {
1336				final ServiceDiscoveryResult value = cursor.getValue();
1337				if (value.getFeatures().contains("http://jabber.org/protocol/muc")
1338						&& !value.getFeatures().contains("jabber:iq:gateway")
1339						&& !value.hasIdentity("conference", "irc")) {
1340					return cursor.getKey().toString();
1341				}
1342			}
1343		}
1344		return null;
1345	}
1346
1347	public int getTimeToNextAttempt() {
1348		final int interval = (int) (25 * Math.pow(1.5, attempt));
1349		final int secondsSinceLast = (int) ((SystemClock.elapsedRealtime() - this.lastConnect) / 1000);
1350		return interval - secondsSinceLast;
1351	}
1352
1353	public int getAttempt() {
1354		return this.attempt;
1355	}
1356
1357	public Features getFeatures() {
1358		return this.features;
1359	}
1360
1361	public long getLastSessionEstablished() {
1362		final long diff = SystemClock.elapsedRealtime() - this.lastSessionStarted;
1363		return System.currentTimeMillis() - diff;
1364	}
1365
1366	public long getLastConnect() {
1367		return this.lastConnect;
1368	}
1369
1370	public long getLastPingSent() {
1371		return this.lastPingSent;
1372	}
1373
1374	public long getLastDiscoStarted() {
1375		return this.lastDiscoStarted;
1376	}
1377	public long getLastPacketReceived() {
1378		return this.lastPacketReceived;
1379	}
1380
1381	public void sendActive() {
1382		this.sendPacket(new ActivePacket());
1383	}
1384
1385	public void sendInactive() {
1386		this.sendPacket(new InactivePacket());
1387	}
1388
1389	public void resetAttemptCount() {
1390		this.attempt = 0;
1391		this.lastConnect = 0;
1392	}
1393
1394	public void setInteractive(boolean interactive) {
1395		this.mInteractive = interactive;
1396	}
1397
1398	public Identity getServerIdentity() {
1399		return mServerIdentity;
1400	}
1401
1402	private class UnauthorizedException extends IOException {
1403
1404	}
1405
1406	private class SecurityException extends IOException {
1407
1408	}
1409
1410	private class IncompatibleServerException extends IOException {
1411
1412	}
1413
1414	public enum Identity {
1415		FACEBOOK,
1416		SLACK,
1417		EJABBERD,
1418		PROSODY,
1419		NIMBUZZ,
1420		UNKNOWN
1421	}
1422
1423	public class Features {
1424		XmppConnection connection;
1425		private boolean carbonsEnabled = false;
1426		private boolean encryptionEnabled = false;
1427		private boolean blockListRequested = false;
1428
1429		public Features(final XmppConnection connection) {
1430			this.connection = connection;
1431		}
1432
1433		private boolean hasDiscoFeature(final Jid server, final String feature) {
1434			synchronized (XmppConnection.this.disco) {
1435				return connection.disco.containsKey(server) &&
1436						connection.disco.get(server).getFeatures().contains(feature);
1437			}
1438		}
1439
1440		public boolean carbons() {
1441			return hasDiscoFeature(account.getServer(), "urn:xmpp:carbons:2");
1442		}
1443
1444		public boolean blocking() {
1445			return hasDiscoFeature(account.getServer(), Xmlns.BLOCKING);
1446		}
1447
1448		public boolean register() {
1449			return hasDiscoFeature(account.getServer(), Xmlns.REGISTER);
1450		}
1451
1452		public boolean sm() {
1453			return streamId != null
1454					|| (connection.streamFeatures != null && connection.streamFeatures.hasChild("sm"));
1455		}
1456
1457		public boolean csi() {
1458			return connection.streamFeatures != null && connection.streamFeatures.hasChild("csi", "urn:xmpp:csi:0");
1459		}
1460
1461		public boolean pep() {
1462			synchronized (XmppConnection.this.disco) {
1463				final Pair<String, String> needle = new Pair<>("pubsub", "pep");
1464				ServiceDiscoveryResult info = disco.get(account.getServer());
1465				if (info != null && info.hasIdentity("pubsub", "pep")) {
1466					return true;
1467				} else {
1468					info = disco.get(account.getJid().toBareJid());
1469					return info != null && info.hasIdentity("pubsub", "pep");
1470				}
1471			}
1472		}
1473
1474		public boolean mam() {
1475			if (hasDiscoFeature(account.getJid().toBareJid(), "urn:xmpp:mam:0")) {
1476				return true;
1477			} else {
1478				return hasDiscoFeature(account.getServer(), "urn:xmpp:mam:0");
1479			}
1480		}
1481
1482		public boolean advancedStreamFeaturesLoaded() {
1483			synchronized (XmppConnection.this.disco) {
1484				return disco.containsKey(account.getServer());
1485			}
1486		}
1487
1488		public boolean rosterVersioning() {
1489			return connection.streamFeatures != null && connection.streamFeatures.hasChild("ver");
1490		}
1491
1492		public void setBlockListRequested(boolean value) {
1493			this.blockListRequested = value;
1494		}
1495
1496		public boolean httpUpload() {
1497			return !Config.DISABLE_HTTP_UPLOAD && findDiscoItemsByFeature(Xmlns.HTTP_UPLOAD).size() > 0;
1498		}
1499	}
1500
1501	private IqGenerator getIqGenerator() {
1502		return mXmppConnectionService.getIqGenerator();
1503	}
1504}