AxolotlService.java

  1package eu.siacs.conversations.crypto.axolotl;
  2
  3import android.support.annotation.NonNull;
  4import android.support.annotation.Nullable;
  5import android.util.Log;
  6
  7import org.bouncycastle.jce.provider.BouncyCastleProvider;
  8import org.whispersystems.libaxolotl.AxolotlAddress;
  9import org.whispersystems.libaxolotl.IdentityKey;
 10import org.whispersystems.libaxolotl.IdentityKeyPair;
 11import org.whispersystems.libaxolotl.InvalidKeyException;
 12import org.whispersystems.libaxolotl.InvalidKeyIdException;
 13import org.whispersystems.libaxolotl.SessionBuilder;
 14import org.whispersystems.libaxolotl.UntrustedIdentityException;
 15import org.whispersystems.libaxolotl.ecc.ECPublicKey;
 16import org.whispersystems.libaxolotl.state.PreKeyBundle;
 17import org.whispersystems.libaxolotl.state.PreKeyRecord;
 18import org.whispersystems.libaxolotl.state.SignedPreKeyRecord;
 19import org.whispersystems.libaxolotl.util.KeyHelper;
 20
 21import java.security.Security;
 22import java.util.Arrays;
 23import java.util.HashMap;
 24import java.util.HashSet;
 25import java.util.List;
 26import java.util.Map;
 27import java.util.Random;
 28import java.util.Set;
 29
 30import eu.siacs.conversations.Config;
 31import eu.siacs.conversations.entities.Account;
 32import eu.siacs.conversations.entities.Contact;
 33import eu.siacs.conversations.entities.Conversation;
 34import eu.siacs.conversations.entities.Message;
 35import eu.siacs.conversations.parser.IqParser;
 36import eu.siacs.conversations.services.XmppConnectionService;
 37import eu.siacs.conversations.utils.SerialSingleThreadExecutor;
 38import eu.siacs.conversations.xml.Element;
 39import eu.siacs.conversations.xmpp.OnIqPacketReceived;
 40import eu.siacs.conversations.xmpp.jid.InvalidJidException;
 41import eu.siacs.conversations.xmpp.jid.Jid;
 42import eu.siacs.conversations.xmpp.stanzas.IqPacket;
 43
 44public class AxolotlService {
 45
 46	public static final String PEP_PREFIX = "eu.siacs.conversations.axolotl";
 47	public static final String PEP_DEVICE_LIST = PEP_PREFIX + ".devicelist";
 48	public static final String PEP_BUNDLES = PEP_PREFIX + ".bundles";
 49
 50	public static final String LOGPREFIX = "AxolotlService";
 51
 52	public static final int NUM_KEYS_TO_PUBLISH = 100;
 53	public static final int publishTriesThreshold = 3;
 54
 55	private final Account account;
 56	private final XmppConnectionService mXmppConnectionService;
 57	private final SQLiteAxolotlStore axolotlStore;
 58	private final SessionMap sessions;
 59	private final Map<Jid, Set<Integer>> deviceIds;
 60	private final Map<String, XmppAxolotlMessage> messageCache;
 61	private final FetchStatusMap fetchStatusMap;
 62	private final SerialSingleThreadExecutor executor;
 63	private int numPublishTriesOnEmptyPep = 0;
 64	private boolean pepBroken = false;
 65
 66	private static class AxolotlAddressMap<T> {
 67		protected Map<String, Map<Integer, T>> map;
 68		protected final Object MAP_LOCK = new Object();
 69
 70		public AxolotlAddressMap() {
 71			this.map = new HashMap<>();
 72		}
 73
 74		public void put(AxolotlAddress address, T value) {
 75			synchronized (MAP_LOCK) {
 76				Map<Integer, T> devices = map.get(address.getName());
 77				if (devices == null) {
 78					devices = new HashMap<>();
 79					map.put(address.getName(), devices);
 80				}
 81				devices.put(address.getDeviceId(), value);
 82			}
 83		}
 84
 85		public T get(AxolotlAddress address) {
 86			synchronized (MAP_LOCK) {
 87				Map<Integer, T> devices = map.get(address.getName());
 88				if (devices == null) {
 89					return null;
 90				}
 91				return devices.get(address.getDeviceId());
 92			}
 93		}
 94
 95		public Map<Integer, T> getAll(AxolotlAddress address) {
 96			synchronized (MAP_LOCK) {
 97				Map<Integer, T> devices = map.get(address.getName());
 98				if (devices == null) {
 99					return new HashMap<>();
100				}
101				return devices;
102			}
103		}
104
105		public boolean hasAny(AxolotlAddress address) {
106			synchronized (MAP_LOCK) {
107				Map<Integer, T> devices = map.get(address.getName());
108				return devices != null && !devices.isEmpty();
109			}
110		}
111
112		public void clear() {
113			map.clear();
114		}
115
116	}
117
118	private static class SessionMap extends AxolotlAddressMap<XmppAxolotlSession> {
119		private final XmppConnectionService xmppConnectionService;
120		private final Account account;
121
122		public SessionMap(XmppConnectionService service, SQLiteAxolotlStore store, Account account) {
123			super();
124			this.xmppConnectionService = service;
125			this.account = account;
126			this.fillMap(store);
127		}
128
129		private void putDevicesForJid(String bareJid, List<Integer> deviceIds, SQLiteAxolotlStore store) {
130			for (Integer deviceId : deviceIds) {
131				AxolotlAddress axolotlAddress = new AxolotlAddress(bareJid, deviceId);
132				Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Building session for remote address: " + axolotlAddress.toString());
133				String fingerprint = store.loadSession(axolotlAddress).getSessionState().getRemoteIdentityKey().getFingerprint().replaceAll("\\s", "");
134				this.put(axolotlAddress, new XmppAxolotlSession(account, store, axolotlAddress, fingerprint));
135			}
136		}
137
138		private void fillMap(SQLiteAxolotlStore store) {
139			List<Integer> deviceIds = store.getSubDeviceSessions(account.getJid().toBareJid().toString());
140			putDevicesForJid(account.getJid().toBareJid().toString(), deviceIds, store);
141			for (Contact contact : account.getRoster().getContacts()) {
142				Jid bareJid = contact.getJid().toBareJid();
143				if (bareJid == null) {
144					continue; // FIXME: handle this?
145				}
146				String address = bareJid.toString();
147				deviceIds = store.getSubDeviceSessions(address);
148				putDevicesForJid(address, deviceIds, store);
149			}
150
151		}
152
153		@Override
154		public void put(AxolotlAddress address, XmppAxolotlSession value) {
155			super.put(address, value);
156			value.setNotFresh();
157			xmppConnectionService.syncRosterToDisk(account);
158		}
159
160		public void put(XmppAxolotlSession session) {
161			this.put(session.getRemoteAddress(), session);
162		}
163	}
164
165	private static enum FetchStatus {
166		PENDING,
167		SUCCESS,
168		ERROR
169	}
170
171	private static class FetchStatusMap extends AxolotlAddressMap<FetchStatus> {
172
173	}
174
175	public static String getLogprefix(Account account) {
176		return LOGPREFIX + " (" + account.getJid().toBareJid().toString() + "): ";
177	}
178
179	public AxolotlService(Account account, XmppConnectionService connectionService) {
180		if (Security.getProvider("BC") == null) {
181			Security.addProvider(new BouncyCastleProvider());
182		}
183		this.mXmppConnectionService = connectionService;
184		this.account = account;
185		this.axolotlStore = new SQLiteAxolotlStore(this.account, this.mXmppConnectionService);
186		this.deviceIds = new HashMap<>();
187		this.messageCache = new HashMap<>();
188		this.sessions = new SessionMap(mXmppConnectionService, axolotlStore, account);
189		this.fetchStatusMap = new FetchStatusMap();
190		this.executor = new SerialSingleThreadExecutor();
191	}
192
193	public String getOwnFingerprint() {
194		return axolotlStore.getIdentityKeyPair().getPublicKey().getFingerprint().replaceAll("\\s", "");
195	}
196
197	public Set<IdentityKey> getKeysWithTrust(XmppAxolotlSession.Trust trust) {
198		return axolotlStore.getContactKeysWithTrust(account.getJid().toBareJid().toString(), trust);
199	}
200
201	public Set<IdentityKey> getKeysWithTrust(XmppAxolotlSession.Trust trust, Contact contact) {
202		return axolotlStore.getContactKeysWithTrust(contact.getJid().toBareJid().toString(), trust);
203	}
204
205	public long getNumTrustedKeys(Contact contact) {
206		return axolotlStore.getContactNumTrustedKeys(contact.getJid().toBareJid().toString());
207	}
208
209	private AxolotlAddress getAddressForJid(Jid jid) {
210		return new AxolotlAddress(jid.toString(), 0);
211	}
212
213	private Set<XmppAxolotlSession> findOwnSessions() {
214		AxolotlAddress ownAddress = getAddressForJid(account.getJid().toBareJid());
215		Set<XmppAxolotlSession> ownDeviceSessions = new HashSet<>(this.sessions.getAll(ownAddress).values());
216		return ownDeviceSessions;
217	}
218
219	private Set<XmppAxolotlSession> findSessionsforContact(Contact contact) {
220		AxolotlAddress contactAddress = getAddressForJid(contact.getJid());
221		Set<XmppAxolotlSession> sessions = new HashSet<>(this.sessions.getAll(contactAddress).values());
222		return sessions;
223	}
224
225	public Set<String> getFingerprintsForOwnSessions() {
226		Set<String> fingerprints = new HashSet<>();
227		for (XmppAxolotlSession session : findOwnSessions()) {
228			fingerprints.add(session.getFingerprint());
229		}
230		return fingerprints;
231	}
232
233	public Set<String> getFingerprintsForContact(final Contact contact) {
234		Set<String> fingerprints = new HashSet<>();
235		for (XmppAxolotlSession session : findSessionsforContact(contact)) {
236			fingerprints.add(session.getFingerprint());
237		}
238		return fingerprints;
239	}
240
241	private boolean hasAny(Contact contact) {
242		AxolotlAddress contactAddress = getAddressForJid(contact.getJid());
243		return sessions.hasAny(contactAddress);
244	}
245
246	public void regenerateKeys() {
247		axolotlStore.regenerate();
248		sessions.clear();
249		fetchStatusMap.clear();
250		publishBundlesIfNeeded(true);
251	}
252
253	public int getOwnDeviceId() {
254		return axolotlStore.getLocalRegistrationId();
255	}
256
257	public Set<Integer> getOwnDeviceIds() {
258		return this.deviceIds.get(account.getJid().toBareJid());
259	}
260
261	private void setTrustOnSessions(final Jid jid, @NonNull final Set<Integer> deviceIds,
262	                                final XmppAxolotlSession.Trust from,
263	                                final XmppAxolotlSession.Trust to) {
264		for (Integer deviceId : deviceIds) {
265			AxolotlAddress address = new AxolotlAddress(jid.toBareJid().toString(), deviceId);
266			XmppAxolotlSession session = sessions.get(address);
267			if (session != null && session.getFingerprint() != null
268					&& session.getTrust() == from) {
269				session.setTrust(to);
270			}
271		}
272	}
273
274	public void registerDevices(final Jid jid, @NonNull final Set<Integer> deviceIds) {
275		if (jid.toBareJid().equals(account.getJid().toBareJid())) {
276			if (!deviceIds.isEmpty()) {
277				Log.d(Config.LOGTAG, getLogprefix(account) + "Received non-empty own device list. Resetting publish attemps and pepBroken status.");
278				pepBroken = false;
279				numPublishTriesOnEmptyPep = 0;
280			}
281			if (deviceIds.contains(getOwnDeviceId())) {
282				deviceIds.remove(getOwnDeviceId());
283			} else {
284				publishOwnDeviceId(deviceIds);
285			}
286			for (Integer deviceId : deviceIds) {
287				AxolotlAddress ownDeviceAddress = new AxolotlAddress(jid.toBareJid().toString(), deviceId);
288				if (sessions.get(ownDeviceAddress) == null) {
289					buildSessionFromPEP(ownDeviceAddress);
290				}
291			}
292		}
293		Set<Integer> expiredDevices = new HashSet<>(axolotlStore.getSubDeviceSessions(jid.toBareJid().toString()));
294		expiredDevices.removeAll(deviceIds);
295		setTrustOnSessions(jid, expiredDevices, XmppAxolotlSession.Trust.TRUSTED,
296				XmppAxolotlSession.Trust.INACTIVE_TRUSTED);
297		setTrustOnSessions(jid, expiredDevices, XmppAxolotlSession.Trust.UNDECIDED,
298				XmppAxolotlSession.Trust.INACTIVE_UNDECIDED);
299		setTrustOnSessions(jid, expiredDevices, XmppAxolotlSession.Trust.UNTRUSTED,
300				XmppAxolotlSession.Trust.INACTIVE_UNTRUSTED);
301		Set<Integer> newDevices = new HashSet<>(deviceIds);
302		setTrustOnSessions(jid, newDevices, XmppAxolotlSession.Trust.INACTIVE_TRUSTED,
303				XmppAxolotlSession.Trust.TRUSTED);
304		setTrustOnSessions(jid, newDevices, XmppAxolotlSession.Trust.INACTIVE_UNDECIDED,
305				XmppAxolotlSession.Trust.UNDECIDED);
306		setTrustOnSessions(jid, newDevices, XmppAxolotlSession.Trust.INACTIVE_UNTRUSTED,
307				XmppAxolotlSession.Trust.UNTRUSTED);
308		this.deviceIds.put(jid, deviceIds);
309		mXmppConnectionService.keyStatusUpdated();
310	}
311
312	public void wipeOtherPepDevices() {
313		if (pepBroken) {
314			Log.d(Config.LOGTAG, getLogprefix(account) + "wipeOtherPepDevices called, but PEP is broken. Ignoring... ");
315			return;
316		}
317		Set<Integer> deviceIds = new HashSet<>();
318		deviceIds.add(getOwnDeviceId());
319		IqPacket publish = mXmppConnectionService.getIqGenerator().publishDeviceIds(deviceIds);
320		Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Wiping all other devices from Pep:" + publish);
321		mXmppConnectionService.sendIqPacket(account, publish, new OnIqPacketReceived() {
322			@Override
323			public void onIqPacketReceived(Account account, IqPacket packet) {
324				// TODO: implement this!
325			}
326		});
327	}
328
329	public void purgeKey(final String fingerprint) {
330		axolotlStore.setFingerprintTrust(fingerprint.replaceAll("\\s", ""), XmppAxolotlSession.Trust.COMPROMISED);
331	}
332
333	public void publishOwnDeviceIdIfNeeded() {
334		if (pepBroken) {
335			Log.d(Config.LOGTAG, getLogprefix(account) + "publishOwnDeviceIdIfNeeded called, but PEP is broken. Ignoring... ");
336			return;
337		}
338		IqPacket packet = mXmppConnectionService.getIqGenerator().retrieveDeviceIds(account.getJid().toBareJid());
339		mXmppConnectionService.sendIqPacket(account, packet, new OnIqPacketReceived() {
340			@Override
341			public void onIqPacketReceived(Account account, IqPacket packet) {
342				if (packet.getType() == IqPacket.TYPE.TIMEOUT) {
343					Log.d(Config.LOGTAG, getLogprefix(account) + "Timeout received while retrieving own Device Ids.");
344				} else {
345					Element item = mXmppConnectionService.getIqParser().getItem(packet);
346					Set<Integer> deviceIds = mXmppConnectionService.getIqParser().deviceIds(item);
347					if (!deviceIds.contains(getOwnDeviceId())) {
348						publishOwnDeviceId(deviceIds);
349					}
350				}
351			}
352		});
353	}
354
355	public void publishOwnDeviceId(Set<Integer> deviceIds) {
356		Set<Integer> deviceIdsCopy = new HashSet<>(deviceIds);
357		if (!deviceIdsCopy.contains(getOwnDeviceId())) {
358			Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Own device " + getOwnDeviceId() + " not in PEP devicelist.");
359			if (deviceIdsCopy.isEmpty()) {
360				if (numPublishTriesOnEmptyPep >= publishTriesThreshold) {
361					Log.w(Config.LOGTAG, getLogprefix(account) + "Own device publish attempt threshold exceeded, aborting...");
362					pepBroken = true;
363					return;
364				} else {
365					numPublishTriesOnEmptyPep++;
366					Log.w(Config.LOGTAG, getLogprefix(account) + "Own device list empty, attempting to publish (try " + numPublishTriesOnEmptyPep + ")");
367				}
368			} else {
369				numPublishTriesOnEmptyPep = 0;
370			}
371			deviceIdsCopy.add(getOwnDeviceId());
372			IqPacket publish = mXmppConnectionService.getIqGenerator().publishDeviceIds(deviceIdsCopy);
373			mXmppConnectionService.sendIqPacket(account, publish, new OnIqPacketReceived() {
374				@Override
375				public void onIqPacketReceived(Account account, IqPacket packet) {
376					if (packet.getType() != IqPacket.TYPE.RESULT) {
377						Log.d(Config.LOGTAG, getLogprefix(account) + "Error received while publishing own device id" + packet.findChild("error"));
378					}
379				}
380			});
381		}
382	}
383
384	public void publishBundlesIfNeeded(final boolean announceAfter) {
385		if (pepBroken) {
386			Log.d(Config.LOGTAG, getLogprefix(account) + "publishBundlesIfNeeded called, but PEP is broken. Ignoring... ");
387			return;
388		}
389		IqPacket packet = mXmppConnectionService.getIqGenerator().retrieveBundlesForDevice(account.getJid().toBareJid(), getOwnDeviceId());
390		mXmppConnectionService.sendIqPacket(account, packet, new OnIqPacketReceived() {
391			@Override
392			public void onIqPacketReceived(Account account, IqPacket packet) {
393				PreKeyBundle bundle = mXmppConnectionService.getIqParser().bundle(packet);
394				Map<Integer, ECPublicKey> keys = mXmppConnectionService.getIqParser().preKeyPublics(packet);
395				boolean flush = false;
396				if (bundle == null) {
397					Log.w(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Received invalid bundle:" + packet);
398					bundle = new PreKeyBundle(-1, -1, -1, null, -1, null, null, null);
399					flush = true;
400				}
401				if (keys == null) {
402					Log.w(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Received invalid prekeys:" + packet);
403				}
404				try {
405					boolean changed = false;
406					// Validate IdentityKey
407					IdentityKeyPair identityKeyPair = axolotlStore.getIdentityKeyPair();
408					if (flush || !identityKeyPair.getPublicKey().equals(bundle.getIdentityKey())) {
409						Log.i(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Adding own IdentityKey " + identityKeyPair.getPublicKey() + " to PEP.");
410						changed = true;
411					}
412
413					// Validate signedPreKeyRecord + ID
414					SignedPreKeyRecord signedPreKeyRecord;
415					int numSignedPreKeys = axolotlStore.loadSignedPreKeys().size();
416					try {
417						signedPreKeyRecord = axolotlStore.loadSignedPreKey(bundle.getSignedPreKeyId());
418						if (flush
419								|| !bundle.getSignedPreKey().equals(signedPreKeyRecord.getKeyPair().getPublicKey())
420								|| !Arrays.equals(bundle.getSignedPreKeySignature(), signedPreKeyRecord.getSignature())) {
421							Log.i(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Adding new signedPreKey with ID " + (numSignedPreKeys + 1) + " to PEP.");
422							signedPreKeyRecord = KeyHelper.generateSignedPreKey(identityKeyPair, numSignedPreKeys + 1);
423							axolotlStore.storeSignedPreKey(signedPreKeyRecord.getId(), signedPreKeyRecord);
424							changed = true;
425						}
426					} catch (InvalidKeyIdException e) {
427						Log.i(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Adding new signedPreKey with ID " + (numSignedPreKeys + 1) + " to PEP.");
428						signedPreKeyRecord = KeyHelper.generateSignedPreKey(identityKeyPair, numSignedPreKeys + 1);
429						axolotlStore.storeSignedPreKey(signedPreKeyRecord.getId(), signedPreKeyRecord);
430						changed = true;
431					}
432
433					// Validate PreKeys
434					Set<PreKeyRecord> preKeyRecords = new HashSet<>();
435					if (keys != null) {
436						for (Integer id : keys.keySet()) {
437							try {
438								PreKeyRecord preKeyRecord = axolotlStore.loadPreKey(id);
439								if (preKeyRecord.getKeyPair().getPublicKey().equals(keys.get(id))) {
440									preKeyRecords.add(preKeyRecord);
441								}
442							} catch (InvalidKeyIdException ignored) {
443							}
444						}
445					}
446					int newKeys = NUM_KEYS_TO_PUBLISH - preKeyRecords.size();
447					if (newKeys > 0) {
448						List<PreKeyRecord> newRecords = KeyHelper.generatePreKeys(
449								axolotlStore.getCurrentPreKeyId() + 1, newKeys);
450						preKeyRecords.addAll(newRecords);
451						for (PreKeyRecord record : newRecords) {
452							axolotlStore.storePreKey(record.getId(), record);
453						}
454						changed = true;
455						Log.i(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Adding " + newKeys + " new preKeys to PEP.");
456					}
457
458
459					if (changed) {
460						IqPacket publish = mXmppConnectionService.getIqGenerator().publishBundles(
461								signedPreKeyRecord, axolotlStore.getIdentityKeyPair().getPublicKey(),
462								preKeyRecords, getOwnDeviceId());
463						Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + ": Bundle " + getOwnDeviceId() + " in PEP not current. Publishing: " + publish);
464						mXmppConnectionService.sendIqPacket(account, publish, new OnIqPacketReceived() {
465							@Override
466							public void onIqPacketReceived(Account account, IqPacket packet) {
467								if (packet.getType() == IqPacket.TYPE.RESULT) {
468									Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Successfully published bundle. ");
469									if (announceAfter) {
470										Log.d(Config.LOGTAG, getLogprefix(account) + "Announcing device " + getOwnDeviceId());
471										publishOwnDeviceIdIfNeeded();
472									}
473								} else {
474									Log.d(Config.LOGTAG, getLogprefix(account) + "Error received while publishing bundle: " + packet.findChild("error"));
475								}
476							}
477						});
478					} else {
479						Log.d(Config.LOGTAG, getLogprefix(account) + "Bundle " + getOwnDeviceId() + " in PEP was current");
480						if (announceAfter) {
481							Log.d(Config.LOGTAG, getLogprefix(account) + "Announcing device " + getOwnDeviceId());
482							publishOwnDeviceIdIfNeeded();
483						}
484					}
485				} catch (InvalidKeyException e) {
486					Log.e(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Failed to publish bundle " + getOwnDeviceId() + ", reason: " + e.getMessage());
487					return;
488				}
489			}
490		});
491	}
492
493	public boolean isContactAxolotlCapable(Contact contact) {
494
495		Jid jid = contact.getJid().toBareJid();
496		AxolotlAddress address = new AxolotlAddress(jid.toString(), 0);
497		return sessions.hasAny(address) ||
498				(deviceIds.containsKey(jid) && !deviceIds.get(jid).isEmpty());
499	}
500
501	public XmppAxolotlSession.Trust getFingerprintTrust(String fingerprint) {
502		return axolotlStore.getFingerprintTrust(fingerprint);
503	}
504
505	public void setFingerprintTrust(String fingerprint, XmppAxolotlSession.Trust trust) {
506		axolotlStore.setFingerprintTrust(fingerprint, trust);
507	}
508
509	private void buildSessionFromPEP(final AxolotlAddress address) {
510		Log.i(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Building new sesstion for " + address.toString());
511		if (address.getDeviceId() == getOwnDeviceId()) {
512			throw new AssertionError("We should NEVER build a session with ourselves. What happened here?!");
513		}
514
515		try {
516			IqPacket bundlesPacket = mXmppConnectionService.getIqGenerator().retrieveBundlesForDevice(
517					Jid.fromString(address.getName()), address.getDeviceId());
518			Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Retrieving bundle: " + bundlesPacket);
519			mXmppConnectionService.sendIqPacket(account, bundlesPacket, new OnIqPacketReceived() {
520				private void finish() {
521					AxolotlAddress ownAddress = new AxolotlAddress(account.getJid().toBareJid().toString(), 0);
522					if (!fetchStatusMap.getAll(ownAddress).containsValue(FetchStatus.PENDING)
523							&& !fetchStatusMap.getAll(address).containsValue(FetchStatus.PENDING)) {
524						mXmppConnectionService.keyStatusUpdated();
525					}
526				}
527
528				@Override
529				public void onIqPacketReceived(Account account, IqPacket packet) {
530					if (packet.getType() == IqPacket.TYPE.RESULT) {
531						Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Received preKey IQ packet, processing...");
532						final IqParser parser = mXmppConnectionService.getIqParser();
533						final List<PreKeyBundle> preKeyBundleList = parser.preKeys(packet);
534						final PreKeyBundle bundle = parser.bundle(packet);
535						if (preKeyBundleList.isEmpty() || bundle == null) {
536							Log.e(Config.LOGTAG, AxolotlService.getLogprefix(account) + "preKey IQ packet invalid: " + packet);
537							fetchStatusMap.put(address, FetchStatus.ERROR);
538							finish();
539							return;
540						}
541						Random random = new Random();
542						final PreKeyBundle preKey = preKeyBundleList.get(random.nextInt(preKeyBundleList.size()));
543						if (preKey == null) {
544							//should never happen
545							fetchStatusMap.put(address, FetchStatus.ERROR);
546							finish();
547							return;
548						}
549
550						final PreKeyBundle preKeyBundle = new PreKeyBundle(0, address.getDeviceId(),
551								preKey.getPreKeyId(), preKey.getPreKey(),
552								bundle.getSignedPreKeyId(), bundle.getSignedPreKey(),
553								bundle.getSignedPreKeySignature(), bundle.getIdentityKey());
554
555						try {
556							SessionBuilder builder = new SessionBuilder(axolotlStore, address);
557							builder.process(preKeyBundle);
558							XmppAxolotlSession session = new XmppAxolotlSession(account, axolotlStore, address, bundle.getIdentityKey().getFingerprint().replaceAll("\\s", ""));
559							sessions.put(address, session);
560							fetchStatusMap.put(address, FetchStatus.SUCCESS);
561						} catch (UntrustedIdentityException | InvalidKeyException e) {
562							Log.e(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Error building session for " + address + ": "
563									+ e.getClass().getName() + ", " + e.getMessage());
564							fetchStatusMap.put(address, FetchStatus.ERROR);
565						}
566
567						finish();
568					} else {
569						fetchStatusMap.put(address, FetchStatus.ERROR);
570						Log.d(Config.LOGTAG, getLogprefix(account) + "Error received while building session:" + packet.findChild("error"));
571						finish();
572						return;
573					}
574				}
575			});
576		} catch (InvalidJidException e) {
577			Log.e(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Got address with invalid jid: " + address.getName());
578		}
579	}
580
581	public Set<AxolotlAddress> findDevicesWithoutSession(final Conversation conversation) {
582		Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Finding devices without session for " + conversation.getContact().getJid().toBareJid());
583		Jid contactJid = conversation.getContact().getJid().toBareJid();
584		Set<AxolotlAddress> addresses = new HashSet<>();
585		if (deviceIds.get(contactJid) != null) {
586			for (Integer foreignId : this.deviceIds.get(contactJid)) {
587				AxolotlAddress address = new AxolotlAddress(contactJid.toString(), foreignId);
588				if (sessions.get(address) == null) {
589					IdentityKey identityKey = axolotlStore.loadSession(address).getSessionState().getRemoteIdentityKey();
590					if (identityKey != null) {
591						Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Already have session for " + address.toString() + ", adding to cache...");
592						XmppAxolotlSession session = new XmppAxolotlSession(account, axolotlStore, address, identityKey.getFingerprint().replaceAll("\\s", ""));
593						sessions.put(address, session);
594					} else {
595						Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Found device " + account.getJid().toBareJid() + ":" + foreignId);
596						addresses.add(new AxolotlAddress(contactJid.toString(), foreignId));
597					}
598				}
599			}
600		} else {
601			Log.w(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Have no target devices in PEP!");
602		}
603		if (deviceIds.get(account.getJid().toBareJid()) != null) {
604			for (Integer ownId : this.deviceIds.get(account.getJid().toBareJid())) {
605				AxolotlAddress address = new AxolotlAddress(account.getJid().toBareJid().toString(), ownId);
606				if (sessions.get(address) == null) {
607					IdentityKey identityKey = axolotlStore.loadSession(address).getSessionState().getRemoteIdentityKey();
608					if (identityKey != null) {
609						Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Already have session for " + address.toString() + ", adding to cache...");
610						XmppAxolotlSession session = new XmppAxolotlSession(account, axolotlStore, address, identityKey.getFingerprint().replaceAll("\\s", ""));
611						sessions.put(address, session);
612					} else {
613						Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Found device " + account.getJid().toBareJid() + ":" + ownId);
614						addresses.add(new AxolotlAddress(account.getJid().toBareJid().toString(), ownId));
615					}
616				}
617			}
618		}
619
620		return addresses;
621	}
622
623	public boolean createSessionsIfNeeded(final Conversation conversation) {
624		Log.i(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Creating axolotl sessions if needed...");
625		boolean newSessions = false;
626		Set<AxolotlAddress> addresses = findDevicesWithoutSession(conversation);
627		for (AxolotlAddress address : addresses) {
628			Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Processing device: " + address.toString());
629			FetchStatus status = fetchStatusMap.get(address);
630			if (status == null || status == FetchStatus.ERROR) {
631				fetchStatusMap.put(address, FetchStatus.PENDING);
632				this.buildSessionFromPEP(address);
633				newSessions = true;
634			} else if (status == FetchStatus.PENDING) {
635				newSessions = true;
636			} else {
637				Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Already fetching bundle for " + address.toString());
638			}
639		}
640
641		return newSessions;
642	}
643
644	public boolean hasPendingKeyFetches(Conversation conversation) {
645		AxolotlAddress ownAddress = new AxolotlAddress(account.getJid().toBareJid().toString(), 0);
646		AxolotlAddress foreignAddress = new AxolotlAddress(conversation.getJid().toBareJid().toString(), 0);
647		return fetchStatusMap.getAll(ownAddress).containsValue(FetchStatus.PENDING)
648				|| fetchStatusMap.getAll(foreignAddress).containsValue(FetchStatus.PENDING);
649
650	}
651
652	@Nullable
653	private XmppAxolotlMessage buildHeader(Contact contact) {
654		final XmppAxolotlMessage axolotlMessage = new XmppAxolotlMessage(
655				contact.getJid().toBareJid(), getOwnDeviceId());
656
657		Set<XmppAxolotlSession> contactSessions = findSessionsforContact(contact);
658		Set<XmppAxolotlSession> ownSessions = findOwnSessions();
659		if (contactSessions.isEmpty()) {
660			return null;
661		}
662		Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Building axolotl foreign keyElements...");
663		for (XmppAxolotlSession session : contactSessions) {
664			Log.v(Config.LOGTAG, AxolotlService.getLogprefix(account) + session.getRemoteAddress().toString());
665			axolotlMessage.addDevice(session);
666		}
667		Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Building axolotl own keyElements...");
668		for (XmppAxolotlSession session : ownSessions) {
669			Log.v(Config.LOGTAG, AxolotlService.getLogprefix(account) + session.getRemoteAddress().toString());
670			axolotlMessage.addDevice(session);
671		}
672
673		return axolotlMessage;
674	}
675
676	@Nullable
677	public XmppAxolotlMessage encrypt(Message message) {
678		XmppAxolotlMessage axolotlMessage = buildHeader(message.getContact());
679
680		if (axolotlMessage != null) {
681			final String content;
682			if (message.hasFileOnRemoteHost()) {
683				content = message.getFileParams().url.toString();
684			} else {
685				content = message.getBody();
686			}
687			try {
688				axolotlMessage.encrypt(content);
689			} catch (CryptoFailedException e) {
690				Log.w(Config.LOGTAG, getLogprefix(account) + "Failed to encrypt message: " + e.getMessage());
691				return null;
692			}
693		}
694
695		return axolotlMessage;
696	}
697
698	public void preparePayloadMessage(final Message message, final boolean delay) {
699		executor.execute(new Runnable() {
700			@Override
701			public void run() {
702				XmppAxolotlMessage axolotlMessage = encrypt(message);
703				if (axolotlMessage == null) {
704					mXmppConnectionService.markMessage(message, Message.STATUS_SEND_FAILED);
705					//mXmppConnectionService.updateConversationUi();
706				} else {
707					Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Generated message, caching: " + message.getUuid());
708					messageCache.put(message.getUuid(), axolotlMessage);
709					mXmppConnectionService.resendMessage(message, delay);
710				}
711			}
712		});
713	}
714
715	public void prepareKeyTransportMessage(final Contact contact, final OnMessageCreatedCallback onMessageCreatedCallback) {
716		executor.execute(new Runnable() {
717			@Override
718			public void run() {
719				XmppAxolotlMessage axolotlMessage = buildHeader(contact);
720				onMessageCreatedCallback.run(axolotlMessage);
721			}
722		});
723	}
724
725	public XmppAxolotlMessage fetchAxolotlMessageFromCache(Message message) {
726		XmppAxolotlMessage axolotlMessage = messageCache.get(message.getUuid());
727		if (axolotlMessage != null) {
728			Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Cache hit: " + message.getUuid());
729			messageCache.remove(message.getUuid());
730		} else {
731			Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Cache miss: " + message.getUuid());
732		}
733		return axolotlMessage;
734	}
735
736	private XmppAxolotlSession recreateUncachedSession(AxolotlAddress address) {
737		IdentityKey identityKey = axolotlStore.loadSession(address).getSessionState().getRemoteIdentityKey();
738		return (identityKey != null)
739				? new XmppAxolotlSession(account, axolotlStore, address,
740						identityKey.getFingerprint().replaceAll("\\s", ""))
741				: null;
742	}
743
744	private XmppAxolotlSession getReceivingSession(XmppAxolotlMessage message) {
745		AxolotlAddress senderAddress = new AxolotlAddress(message.getFrom().toString(),
746				message.getSenderDeviceId());
747		XmppAxolotlSession session = sessions.get(senderAddress);
748		if (session == null) {
749			Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Account: " + account.getJid() + " No axolotl session found while parsing received message " + message);
750			session = recreateUncachedSession(senderAddress);
751			if (session == null) {
752				session = new XmppAxolotlSession(account, axolotlStore, senderAddress);
753			}
754		}
755		return session;
756	}
757
758	public XmppAxolotlMessage.XmppAxolotlPlaintextMessage processReceivingPayloadMessage(XmppAxolotlMessage message) {
759		XmppAxolotlMessage.XmppAxolotlPlaintextMessage plaintextMessage = null;
760
761		XmppAxolotlSession session = getReceivingSession(message);
762		try {
763			plaintextMessage = message.decrypt(session, getOwnDeviceId());
764			Integer preKeyId = session.getPreKeyId();
765			if (preKeyId != null) {
766				publishBundlesIfNeeded(false);
767				session.resetPreKeyId();
768			}
769		} catch (CryptoFailedException e) {
770			Log.w(Config.LOGTAG, getLogprefix(account) + "Failed to decrypt message: " + e.getMessage());
771		}
772
773		if (session.isFresh() && plaintextMessage != null) {
774			sessions.put(session);
775		}
776
777		return plaintextMessage;
778	}
779
780	public XmppAxolotlMessage.XmppAxolotlKeyTransportMessage processReceivingKeyTransportMessage(XmppAxolotlMessage message) {
781		XmppAxolotlMessage.XmppAxolotlKeyTransportMessage keyTransportMessage = null;
782
783		XmppAxolotlSession session = getReceivingSession(message);
784		keyTransportMessage = message.getParameters(session, getOwnDeviceId());
785
786		if (session.isFresh() && keyTransportMessage != null) {
787			sessions.put(session);
788		}
789
790		return keyTransportMessage;
791	}
792}