1package eu.siacs.conversations.parser;
  2
  3import android.util.Log;
  4import android.util.Pair;
  5
  6import eu.siacs.conversations.crypto.PgpDecryptionService;
  7import net.java.otr4j.session.Session;
  8import net.java.otr4j.session.SessionStatus;
  9
 10import java.util.ArrayList;
 11import java.util.Set;
 12import java.util.UUID;
 13
 14import eu.siacs.conversations.Config;
 15import eu.siacs.conversations.crypto.axolotl.AxolotlService;
 16import eu.siacs.conversations.crypto.axolotl.XmppAxolotlMessage;
 17import eu.siacs.conversations.entities.Account;
 18import eu.siacs.conversations.entities.Bookmark;
 19import eu.siacs.conversations.entities.Contact;
 20import eu.siacs.conversations.entities.Conversation;
 21import eu.siacs.conversations.entities.Message;
 22import eu.siacs.conversations.entities.MucOptions;
 23import eu.siacs.conversations.http.HttpConnectionManager;
 24import eu.siacs.conversations.services.MessageArchiveService;
 25import eu.siacs.conversations.services.XmppConnectionService;
 26import eu.siacs.conversations.utils.CryptoHelper;
 27import eu.siacs.conversations.xml.Element;
 28import eu.siacs.conversations.xmpp.OnMessagePacketReceived;
 29import eu.siacs.conversations.xmpp.chatstate.ChatState;
 30import eu.siacs.conversations.xmpp.jid.Jid;
 31import eu.siacs.conversations.xmpp.pep.Avatar;
 32import eu.siacs.conversations.xmpp.stanzas.MessagePacket;
 33
 34public class MessageParser extends AbstractParser implements
 35		OnMessagePacketReceived {
 36	public MessageParser(XmppConnectionService service) {
 37		super(service);
 38	}
 39
 40	private boolean extractChatState(Conversation conversation, final MessagePacket packet) {
 41		ChatState state = ChatState.parse(packet);
 42		if (state != null && conversation != null) {
 43			final Account account = conversation.getAccount();
 44			Jid from = packet.getFrom();
 45			if (from.toBareJid().equals(account.getJid().toBareJid())) {
 46				conversation.setOutgoingChatState(state);
 47				if (state == ChatState.ACTIVE || state == ChatState.COMPOSING) {
 48					mXmppConnectionService.markRead(conversation);
 49					account.activateGracePeriod();
 50				}
 51				return false;
 52			} else {
 53				return conversation.setIncomingChatState(state);
 54			}
 55		}
 56		return false;
 57	}
 58
 59	private Message parseOtrChat(String body, Jid from, String id, Conversation conversation) {
 60		String presence;
 61		if (from.isBareJid()) {
 62			presence = "";
 63		} else {
 64			presence = from.getResourcepart();
 65		}
 66		if (body.matches("^\\?OTRv\\d{1,2}\\?.*")) {
 67			conversation.endOtrIfNeeded();
 68		}
 69		if (!conversation.hasValidOtrSession()) {
 70			conversation.startOtrSession(presence,false);
 71		} else {
 72			String foreignPresence = conversation.getOtrSession().getSessionID().getUserID();
 73			if (!foreignPresence.equals(presence)) {
 74				conversation.endOtrIfNeeded();
 75				conversation.startOtrSession(presence, false);
 76			}
 77		}
 78		try {
 79			conversation.setLastReceivedOtrMessageId(id);
 80			Session otrSession = conversation.getOtrSession();
 81			body = otrSession.transformReceiving(body);
 82			SessionStatus status = otrSession.getSessionStatus();
 83			if (body == null && status == SessionStatus.ENCRYPTED) {
 84				mXmppConnectionService.onOtrSessionEstablished(conversation);
 85				return null;
 86			} else if (body == null && status == SessionStatus.FINISHED) {
 87				conversation.resetOtrSession();
 88				mXmppConnectionService.updateConversationUi();
 89				return null;
 90			} else if (body == null || (body.isEmpty())) {
 91				return null;
 92			}
 93			if (body.startsWith(CryptoHelper.FILETRANSFER)) {
 94				String key = body.substring(CryptoHelper.FILETRANSFER.length());
 95				conversation.setSymmetricKey(CryptoHelper.hexToBytes(key));
 96				return null;
 97			}
 98			Message finishedMessage = new Message(conversation, body, Message.ENCRYPTION_OTR, Message.STATUS_RECEIVED);
 99			conversation.setLastReceivedOtrMessageId(null);
100			return finishedMessage;
101		} catch (Exception e) {
102			conversation.resetOtrSession();
103			return null;
104		}
105	}
106
107	private Message parseAxolotlChat(Element axolotlMessage, Jid from, String id, Conversation conversation, int status) {
108		Message finishedMessage = null;
109		AxolotlService service = conversation.getAccount().getAxolotlService();
110		XmppAxolotlMessage xmppAxolotlMessage = XmppAxolotlMessage.fromElement(axolotlMessage, from.toBareJid());
111		XmppAxolotlMessage.XmppAxolotlPlaintextMessage plaintextMessage = service.processReceivingPayloadMessage(xmppAxolotlMessage);
112		if(plaintextMessage != null) {
113			finishedMessage = new Message(conversation, plaintextMessage.getPlaintext(), Message.ENCRYPTION_AXOLOTL, status);
114			finishedMessage.setAxolotlFingerprint(plaintextMessage.getFingerprint());
115			Log.d(Config.LOGTAG, AxolotlService.getLogprefix(finishedMessage.getConversation().getAccount())+" Received Message with session fingerprint: "+plaintextMessage.getFingerprint());
116		}
117
118		return finishedMessage;
119	}
120
121	private class Invite {
122		Jid jid;
123		String password;
124		Invite(Jid jid, String password) {
125			this.jid = jid;
126			this.password = password;
127		}
128
129		public boolean execute(Account account) {
130			if (jid != null) {
131				Conversation conversation = mXmppConnectionService.findOrCreateConversation(account, jid, true);
132				if (!conversation.getMucOptions().online()) {
133					conversation.getMucOptions().setPassword(password);
134					mXmppConnectionService.databaseBackend.updateConversation(conversation);
135					mXmppConnectionService.joinMuc(conversation);
136					mXmppConnectionService.updateConversationUi();
137				}
138				return true;
139			}
140			return false;
141		}
142	}
143
144	private Invite extractInvite(Element message) {
145		Element x = message.findChild("x", "http://jabber.org/protocol/muc#user");
146		if (x != null) {
147			Element invite = x.findChild("invite");
148			if (invite != null) {
149				Element pw = x.findChild("password");
150				return new Invite(message.getAttributeAsJid("from"), pw != null ? pw.getContent(): null);
151			}
152		} else {
153			x = message.findChild("x","jabber:x:conference");
154			if (x != null) {
155				return new Invite(x.getAttributeAsJid("jid"),x.getAttribute("password"));
156			}
157		}
158		return null;
159	}
160
161	private static String extractStanzaId(Element packet, Jid by) {
162		for(Element child : packet.getChildren()) {
163			if (child.getName().equals("stanza-id")
164					&& "urn:xmpp:sid:0".equals(child.getNamespace())
165					&& by.equals(child.getAttributeAsJid("by"))) {
166				return child.getAttribute("id");
167			}
168		}
169		return null;
170	}
171
172	private void parseEvent(final Element event, final Jid from, final Account account) {
173		Element items = event.findChild("items");
174		String node = items == null ? null : items.getAttribute("node");
175		if ("urn:xmpp:avatar:metadata".equals(node)) {
176			Avatar avatar = Avatar.parseMetadata(items);
177			if (avatar != null) {
178				avatar.owner = from.toBareJid();
179				if (mXmppConnectionService.getFileBackend().isAvatarCached(avatar)) {
180					if (account.getJid().toBareJid().equals(from)) {
181						if (account.setAvatar(avatar.getFilename())) {
182							mXmppConnectionService.databaseBackend.updateAccount(account);
183						}
184						mXmppConnectionService.getAvatarService().clear(account);
185						mXmppConnectionService.updateConversationUi();
186						mXmppConnectionService.updateAccountUi();
187					} else {
188						Contact contact = account.getRoster().getContact(from);
189						contact.setAvatar(avatar);
190						mXmppConnectionService.getAvatarService().clear(contact);
191						mXmppConnectionService.updateConversationUi();
192						mXmppConnectionService.updateRosterUi();
193					}
194				} else {
195					mXmppConnectionService.fetchAvatar(account, avatar);
196				}
197			}
198		} else if ("http://jabber.org/protocol/nick".equals(node)) {
199			Element i = items.findChild("item");
200			Element nick = i == null ? null : i.findChild("nick", "http://jabber.org/protocol/nick");
201			if (nick != null && nick.getContent() != null) {
202				Contact contact = account.getRoster().getContact(from);
203				contact.setPresenceName(nick.getContent());
204				mXmppConnectionService.getAvatarService().clear(account);
205				mXmppConnectionService.updateConversationUi();
206				mXmppConnectionService.updateAccountUi();
207			}
208		} else if (AxolotlService.PEP_DEVICE_LIST.equals(node)) {
209			Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account)+"Received PEP device list update from "+ from + ", processing...");
210			Element item = items.findChild("item");
211			Set<Integer> deviceIds = mXmppConnectionService.getIqParser().deviceIds(item);
212			AxolotlService axolotlService = account.getAxolotlService();
213			axolotlService.registerDevices(from, deviceIds);
214			mXmppConnectionService.updateAccountUi();
215		}
216	}
217
218	private boolean handleErrorMessage(Account account, MessagePacket packet) {
219		if (packet.getType() == MessagePacket.TYPE_ERROR) {
220			Jid from = packet.getFrom();
221			if (from != null) {
222				Element error = packet.findChild("error");
223				String text = error == null ? null : error.findChildContent("text");
224				if (text != null) {
225					Log.d(Config.LOGTAG, account.getJid().toBareJid() + ": sending message to "+ from+ " failed - " + text);
226				} else if (error != null) {
227					Log.d(Config.LOGTAG, account.getJid().toBareJid() + ": sending message to "+ from+ " failed - " + error);
228				}
229				Message message = mXmppConnectionService.markMessage(account,
230						from.toBareJid(),
231						packet.getId(),
232						Message.STATUS_SEND_FAILED);
233				if (message != null && message.getEncryption() == Message.ENCRYPTION_OTR) {
234					message.getConversation().endOtrIfNeeded();
235				}
236			}
237			return true;
238		}
239		return false;
240	}
241
242	@Override
243	public void onMessagePacketReceived(Account account, MessagePacket original) {
244		if (handleErrorMessage(account, original)) {
245			return;
246		}
247		final MessagePacket packet;
248		Long timestamp = null;
249		final boolean isForwarded;
250		boolean isCarbon = false;
251		String serverMsgId = null;
252		final Element fin = original.findChild("fin", "urn:xmpp:mam:0");
253		if (fin != null) {
254			mXmppConnectionService.getMessageArchiveService().processFin(fin,original.getFrom());
255			return;
256		}
257		final Element result = original.findChild("result","urn:xmpp:mam:0");
258		final MessageArchiveService.Query query = result == null ? null : mXmppConnectionService.getMessageArchiveService().findQuery(result.getAttribute("queryid"));
259		if (query != null && query.validFrom(original.getFrom())) {
260			Pair<MessagePacket, Long> f = original.getForwardedMessagePacket("result", "urn:xmpp:mam:0");
261			if (f == null) {
262				return;
263			}
264			timestamp = f.second;
265			packet = f.first;
266			isForwarded = true;
267			serverMsgId = result.getAttribute("id");
268			query.incrementMessageCount();
269		} else if (query != null) {
270			Log.d(Config.LOGTAG,account.getJid().toBareJid()+": received mam result from invalid sender");
271			return;
272		} else if (original.fromServer(account)) {
273			Pair<MessagePacket, Long> f;
274			f = original.getForwardedMessagePacket("received", "urn:xmpp:carbons:2");
275			f = f == null ? original.getForwardedMessagePacket("sent", "urn:xmpp:carbons:2") : f;
276			packet = f != null ? f.first : original;
277			if (handleErrorMessage(account, packet)) {
278				return;
279			}
280			timestamp = f != null ? f.second : null;
281			isCarbon = f != null;
282			isForwarded = isCarbon;
283		} else {
284			packet = original;
285			isForwarded = false;
286		}
287
288		if (timestamp == null) {
289			timestamp = AbstractParser.getTimestamp(packet, System.currentTimeMillis());
290		}
291		final String body = packet.getBody();
292		final Element mucUserElement = packet.findChild("x", "http://jabber.org/protocol/muc#user");
293		final String pgpEncrypted = packet.findChildContent("x", "jabber:x:encrypted");
294		final Element replaceElement = packet.findChild("replace","urn:xmpp:message-correct:0");
295		final String replacementId = replaceElement == null ? null : replaceElement.getAttribute("id");
296		final Element axolotlEncrypted = packet.findChild(XmppAxolotlMessage.CONTAINERTAG, AxolotlService.PEP_PREFIX);
297		int status;
298		final Jid counterpart;
299		final Jid to = packet.getTo();
300		final Jid from = packet.getFrom();
301		final String remoteMsgId = packet.getId();
302
303		if (from == null) {
304			Log.d(Config.LOGTAG,"no from in: "+packet.toString());
305			return;
306		}
307		
308		boolean isTypeGroupChat = packet.getType() == MessagePacket.TYPE_GROUPCHAT;
309		boolean isProperlyAddressed = (to != null ) && (!to.isBareJid() || account.countPresences() <= 1);
310		boolean isMucStatusMessage = from.isBareJid() && mucUserElement != null && mucUserElement.hasChild("status");
311		if (packet.fromAccount(account)) {
312			status = Message.STATUS_SEND;
313			counterpart = to != null ? to : account.getJid();
314		} else {
315			status = Message.STATUS_RECEIVED;
316			counterpart = from;
317		}
318
319		Invite invite = extractInvite(packet);
320		if (invite != null && invite.execute(account)) {
321			return;
322		}
323
324		if (extractChatState(mXmppConnectionService.find(account, counterpart.toBareJid()), packet)) {
325			mXmppConnectionService.updateConversationUi();
326		}
327
328		if ((body != null || pgpEncrypted != null || axolotlEncrypted != null) && !isMucStatusMessage) {
329			Conversation conversation = mXmppConnectionService.findOrCreateConversation(account, counterpart.toBareJid(), isTypeGroupChat, query);
330			if (isTypeGroupChat) {
331				if (counterpart.getResourcepart().equals(conversation.getMucOptions().getActualNick())) {
332					status = Message.STATUS_SEND_RECEIVED;
333					isCarbon = true; //not really carbon but received from another resource
334					if (mXmppConnectionService.markMessage(conversation, remoteMsgId, status)) {
335						return;
336					} else if (remoteMsgId == null || Config.IGNORE_ID_REWRITE_IN_MUC) {
337						Message message = conversation.findSentMessageWithBody(packet.getBody());
338						if (message != null) {
339							mXmppConnectionService.markMessage(message, status);
340							return;
341						}
342					}
343				} else {
344					status = Message.STATUS_RECEIVED;
345				}
346			}
347			Message message;
348			if (body != null && body.startsWith("?OTR")) {
349				if (!isForwarded && !isTypeGroupChat && isProperlyAddressed) {
350					message = parseOtrChat(body, from, remoteMsgId, conversation);
351					if (message == null) {
352						return;
353					}
354				} else {
355					Log.d(Config.LOGTAG,account.getJid().toBareJid()+": ignoring OTR message from "+from+" isForwarded="+Boolean.toString(isForwarded)+", isProperlyAddressed="+Boolean.valueOf(isProperlyAddressed));
356					message = new Message(conversation, body, Message.ENCRYPTION_NONE, status);
357				}
358			} else if (pgpEncrypted != null) {
359				message = new Message(conversation, pgpEncrypted, Message.ENCRYPTION_PGP, status);
360			} else if (axolotlEncrypted != null) {
361				message = parseAxolotlChat(axolotlEncrypted, from, remoteMsgId, conversation, status);
362				if (message == null) {
363					return;
364				}
365			} else {
366				message = new Message(conversation, body, Message.ENCRYPTION_NONE, status);
367			}
368
369			if (serverMsgId == null) {
370				serverMsgId = extractStanzaId(packet, isTypeGroupChat ? conversation.getJid().toBareJid() : account.getServer());
371			}
372
373			message.setCounterpart(counterpart);
374			message.setRemoteMsgId(remoteMsgId);
375			message.setServerMsgId(serverMsgId);
376			message.setCarbon(isCarbon);
377			message.setTime(timestamp);
378			message.markable = packet.hasChild("markable", "urn:xmpp:chat-markers:0");
379			if (conversation.getMode() == Conversation.MODE_MULTI) {
380				Jid trueCounterpart = conversation.getMucOptions().getTrueCounterpart(counterpart.getResourcepart());
381				message.setTrueCounterpart(trueCounterpart);
382				if (trueCounterpart != null) {
383					updateLastseen(timestamp, account, trueCounterpart, false);
384				}
385				if (!isTypeGroupChat) {
386					message.setType(Message.TYPE_PRIVATE);
387				}
388			} else {
389				updateLastseen(timestamp, account, packet.getFrom(), true);
390			}
391
392			if (replacementId != null && mXmppConnectionService.allowMessageCorrection()) {
393				Message replacedMessage = conversation.findMessageWithRemoteIdAndCounterpart(replacementId,
394						counterpart,
395						message.getStatus() == Message.STATUS_RECEIVED,
396						message.isCarbon());
397				if (replacedMessage != null) {
398					final boolean fingerprintsMatch = replacedMessage.getAxolotlFingerprint() == null
399							|| replacedMessage.getAxolotlFingerprint().equals(message.getAxolotlFingerprint());
400					final boolean trueCountersMatch = replacedMessage.getTrueCounterpart() != null
401							&& replacedMessage.getTrueCounterpart().equals(message.getTrueCounterpart());
402					if (fingerprintsMatch && (trueCountersMatch || conversation.getMode() == Conversation.MODE_SINGLE)) {
403						Log.d(Config.LOGTAG, "replaced message '" + replacedMessage.getBody() + "' with '" + message.getBody() + "'");
404						final String uuid = replacedMessage.getUuid();
405						replacedMessage.setUuid(UUID.randomUUID().toString());
406						replacedMessage.setBody(message.getBody());
407						replacedMessage.setEdited(replacedMessage.getRemoteMsgId());
408						replacedMessage.setRemoteMsgId(remoteMsgId);
409						replacedMessage.setEncryption(message.getEncryption());
410						if (replacedMessage.getStatus() == Message.STATUS_RECEIVED) {
411							replacedMessage.markUnread();
412						}
413						mXmppConnectionService.updateMessage(replacedMessage, uuid);
414						if (mXmppConnectionService.confirmMessages() && remoteMsgId != null && !isForwarded && !isTypeGroupChat) {
415							sendMessageReceipts(account, packet);
416						}
417						if (replacedMessage.getEncryption() == Message.ENCRYPTION_PGP) {
418							conversation.getAccount().getPgpDecryptionService().add(replacedMessage);
419						}
420						return;
421					} else {
422						Log.d(Config.LOGTAG,account.getJid().toBareJid()+": received message correction but verification didn't check out");
423					}
424				}
425			}
426
427			boolean checkForDuplicates = query != null
428					|| (isTypeGroupChat && packet.hasChild("delay","urn:xmpp:delay"))
429					|| message.getType() == Message.TYPE_PRIVATE;
430			if (checkForDuplicates && conversation.hasDuplicateMessage(message)) {
431				Log.d(Config.LOGTAG,"skipping duplicate message from "+message.getCounterpart().toString()+" "+message.getBody());
432				return;
433			}
434
435			if (query != null && query.getPagingOrder() == MessageArchiveService.PagingOrder.REVERSE) {
436				conversation.prepend(message);
437			} else {
438				conversation.add(message);
439			}
440
441			if (message.getEncryption() == Message.ENCRYPTION_PGP) {
442				conversation.getAccount().getPgpDecryptionService().add(message);
443			}
444
445			if (query == null || query.getWith() == null) { //either no mam or catchup
446				if (status == Message.STATUS_SEND || status == Message.STATUS_SEND_RECEIVED) {
447					mXmppConnectionService.markRead(conversation);
448					if (query == null) {
449						account.activateGracePeriod();
450					}
451				} else {
452					message.markUnread();
453				}
454			}
455
456			if (query == null) {
457				mXmppConnectionService.updateConversationUi();
458			}
459
460			if (mXmppConnectionService.confirmMessages() && remoteMsgId != null && !isForwarded && !isTypeGroupChat) {
461				sendMessageReceipts(account, packet);
462			}
463
464			if (message.getStatus() == Message.STATUS_RECEIVED
465					&& conversation.getOtrSession() != null
466					&& !conversation.getOtrSession().getSessionID().getUserID()
467					.equals(message.getCounterpart().getResourcepart())) {
468				conversation.endOtrIfNeeded();
469			}
470
471			if (message.getEncryption() == Message.ENCRYPTION_NONE || mXmppConnectionService.saveEncryptedMessages()) {
472				mXmppConnectionService.databaseBackend.createMessage(message);
473			}
474			final HttpConnectionManager manager = this.mXmppConnectionService.getHttpConnectionManager();
475			if (message.trusted() && message.treatAsDownloadable() != Message.Decision.NEVER && manager.getAutoAcceptFileSize() > 0) {
476				manager.createNewDownloadConnection(message);
477			} else if (!message.isRead()) {
478				if (query == null) {
479					mXmppConnectionService.getNotificationService().push(message);
480				} else if (query.getWith() == null) { // mam catchup
481					mXmppConnectionService.getNotificationService().pushFromBacklog(message);
482				}
483			}
484		} else if (!packet.hasChild("body")){ //no body
485			if (isTypeGroupChat) {
486				Conversation conversation = mXmppConnectionService.find(account, from.toBareJid());
487				if (packet.hasChild("subject")) {
488					if (conversation != null && conversation.getMode() == Conversation.MODE_MULTI) {
489						conversation.setHasMessagesLeftOnServer(conversation.countMessages() > 0);
490						String subject = packet.findChildContent("subject");
491						conversation.getMucOptions().setSubject(subject);
492						final Bookmark bookmark = conversation.getBookmark();
493						if (bookmark != null && bookmark.getBookmarkName() == null) {
494							if (bookmark.setBookmarkName(subject)) {
495								mXmppConnectionService.pushBookmarks(account);
496							}
497						}
498						mXmppConnectionService.updateConversationUi();
499						return;
500					}
501				}
502
503				if (conversation != null && isMucStatusMessage) {
504					for (Element child : mucUserElement.getChildren()) {
505						if (child.getName().equals("status")
506								&& MucOptions.STATUS_CODE_ROOM_CONFIG_CHANGED.equals(child.getAttribute("code"))) {
507							mXmppConnectionService.fetchConferenceConfiguration(conversation);
508						}
509					}
510				}
511			}
512		}
513
514		Element received = packet.findChild("received", "urn:xmpp:chat-markers:0");
515		if (received == null) {
516			received = packet.findChild("received", "urn:xmpp:receipts");
517		}
518		if (received != null && !packet.fromAccount(account)) {
519			mXmppConnectionService.markMessage(account, from.toBareJid(), received.getAttribute("id"), Message.STATUS_SEND_RECEIVED);
520		}
521		Element displayed = packet.findChild("displayed", "urn:xmpp:chat-markers:0");
522		if (displayed != null) {
523			if (packet.fromAccount(account)) {
524				Conversation conversation = mXmppConnectionService.find(account,counterpart.toBareJid());
525				if (conversation != null) {
526					mXmppConnectionService.markRead(conversation);
527				}
528			} else {
529				updateLastseen(timestamp, account, packet.getFrom(), true);
530				final Message displayedMessage = mXmppConnectionService.markMessage(account, from.toBareJid(), displayed.getAttribute("id"), Message.STATUS_SEND_DISPLAYED);
531				Message message = displayedMessage == null ? null : displayedMessage.prev();
532				while (message != null
533						&& message.getStatus() == Message.STATUS_SEND_RECEIVED
534						&& message.getTimeSent() < displayedMessage.getTimeSent()) {
535					mXmppConnectionService.markMessage(message, Message.STATUS_SEND_DISPLAYED);
536					message = message.prev();
537				}
538			}
539		}
540
541		Element event = packet.findChild("event", "http://jabber.org/protocol/pubsub#event");
542		if (event != null) {
543			parseEvent(event, from, account);
544		}
545
546		String nick = packet.findChildContent("nick", "http://jabber.org/protocol/nick");
547		if (nick != null) {
548			Contact contact = account.getRoster().getContact(from);
549			contact.setPresenceName(nick);
550		}
551	}
552
553	private void sendMessageReceipts(Account account, MessagePacket packet) {
554		ArrayList<String> receiptsNamespaces = new ArrayList<>();
555		if (packet.hasChild("markable", "urn:xmpp:chat-markers:0")) {
556			receiptsNamespaces.add("urn:xmpp:chat-markers:0");
557		}
558		if (packet.hasChild("request", "urn:xmpp:receipts")) {
559			receiptsNamespaces.add("urn:xmpp:receipts");
560		}
561		if (receiptsNamespaces.size() > 0) {
562			MessagePacket receipt = mXmppConnectionService.getMessageGenerator().received(account,
563					packet,
564					receiptsNamespaces,
565					packet.getType());
566			mXmppConnectionService.sendMessagePacket(account, receipt);
567		}
568	}
569}