AxolotlService.java

   1package eu.siacs.conversations.crypto.axolotl;
   2
   3import android.os.Bundle;
   4import android.security.KeyChain;
   5import android.support.annotation.NonNull;
   6import android.support.annotation.Nullable;
   7import android.util.Log;
   8import android.util.Pair;
   9
  10import org.bouncycastle.jce.provider.BouncyCastleProvider;
  11import org.whispersystems.libsignal.SignalProtocolAddress;
  12import org.whispersystems.libsignal.IdentityKey;
  13import org.whispersystems.libsignal.IdentityKeyPair;
  14import org.whispersystems.libsignal.InvalidKeyException;
  15import org.whispersystems.libsignal.InvalidKeyIdException;
  16import org.whispersystems.libsignal.SessionBuilder;
  17import org.whispersystems.libsignal.UntrustedIdentityException;
  18import org.whispersystems.libsignal.ecc.ECPublicKey;
  19import org.whispersystems.libsignal.state.PreKeyBundle;
  20import org.whispersystems.libsignal.state.PreKeyRecord;
  21import org.whispersystems.libsignal.state.SignedPreKeyRecord;
  22import org.whispersystems.libsignal.util.KeyHelper;
  23
  24import java.security.PrivateKey;
  25import java.security.Security;
  26import java.security.Signature;
  27import java.security.cert.X509Certificate;
  28import java.util.ArrayList;
  29import java.util.Arrays;
  30import java.util.Collection;
  31import java.util.Collections;
  32import java.util.HashMap;
  33import java.util.HashSet;
  34import java.util.Iterator;
  35import java.util.List;
  36import java.util.Map;
  37import java.util.Random;
  38import java.util.Set;
  39import java.util.concurrent.atomic.AtomicBoolean;
  40
  41import eu.siacs.conversations.Config;
  42import eu.siacs.conversations.entities.Account;
  43import eu.siacs.conversations.entities.Contact;
  44import eu.siacs.conversations.entities.Conversation;
  45import eu.siacs.conversations.entities.Message;
  46import eu.siacs.conversations.parser.IqParser;
  47import eu.siacs.conversations.services.XmppConnectionService;
  48import eu.siacs.conversations.utils.CryptoHelper;
  49import eu.siacs.conversations.utils.SerialSingleThreadExecutor;
  50import eu.siacs.conversations.xml.Element;
  51import eu.siacs.conversations.xmpp.OnAdvancedStreamFeaturesLoaded;
  52import eu.siacs.conversations.xmpp.OnIqPacketReceived;
  53import eu.siacs.conversations.xmpp.pep.PublishOptions;
  54import eu.siacs.conversations.xmpp.stanzas.IqPacket;
  55import eu.siacs.conversations.xmpp.stanzas.MessagePacket;
  56import rocks.xmpp.addr.Jid;
  57
  58public class AxolotlService implements OnAdvancedStreamFeaturesLoaded {
  59
  60	public static final String PEP_PREFIX = "eu.siacs.conversations.axolotl";
  61	public static final String PEP_DEVICE_LIST = PEP_PREFIX + ".devicelist";
  62	public static final String PEP_DEVICE_LIST_NOTIFY = PEP_DEVICE_LIST + "+notify";
  63	public static final String PEP_BUNDLES = PEP_PREFIX + ".bundles";
  64	public static final String PEP_VERIFICATION = PEP_PREFIX + ".verification";
  65	public static final String PEP_OMEMO_WHITELISTED = PEP_PREFIX + ".whitelisted";
  66
  67	public static final String LOGPREFIX = "AxolotlService";
  68
  69	private static final int NUM_KEYS_TO_PUBLISH = 100;
  70	private static final int publishTriesThreshold = 3;
  71
  72	private final Account account;
  73	private final XmppConnectionService mXmppConnectionService;
  74	private final SQLiteAxolotlStore axolotlStore;
  75	private final SessionMap sessions;
  76	private final Map<Jid, Set<Integer>> deviceIds;
  77	private final Map<String, XmppAxolotlMessage> messageCache;
  78	private final FetchStatusMap fetchStatusMap;
  79	private final Map<Jid, Boolean> fetchDeviceListStatus = new HashMap<>();
  80	private final HashMap<Jid, List<OnDeviceIdsFetched>> fetchDeviceIdsMap = new HashMap<>();
  81	private final SerialSingleThreadExecutor executor;
  82	private int numPublishTriesOnEmptyPep = 0;
  83	private boolean pepBroken = false;
  84	private final Set<SignalProtocolAddress> healingAttempts = new HashSet<>();
  85	private int lastDeviceListNotificationHash = 0;
  86	private final HashSet<Integer> cleanedOwnDeviceIds = new HashSet<>();
  87	private Set<XmppAxolotlSession> postponedSessions = new HashSet<>(); //sessions stored here will receive after mam catchup treatment
  88	private Set<SignalProtocolAddress> postponedHealing = new HashSet<>(); //addresses stored here will need a healing notification after mam catchup
  89
  90	private AtomicBoolean changeAccessMode = new AtomicBoolean(false);
  91
  92	@Override
  93	public void onAdvancedStreamFeaturesAvailable(Account account) {
  94		if (Config.supportOmemo()
  95				&& account.getXmppConnection() != null
  96				&& account.getXmppConnection().getFeatures().pep()) {
  97			publishBundlesIfNeeded(true, false);
  98		} else {
  99			Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": skipping OMEMO initialization");
 100		}
 101	}
 102
 103	private boolean hasErrorFetchingDeviceList(Jid jid) {
 104		Boolean status = fetchDeviceListStatus.get(jid);
 105		return status != null && !status;
 106	}
 107
 108	public boolean hasErrorFetchingDeviceList(List<Jid> jids) {
 109		for(Jid jid : jids) {
 110			if (hasErrorFetchingDeviceList(jid)) {
 111				return true;
 112			}
 113		}
 114		return false;
 115	}
 116
 117	public boolean fetchMapHasErrors(List<Jid> jids) {
 118		for (Jid jid : jids) {
 119			if (deviceIds.get(jid) != null) {
 120				for (Integer foreignId : this.deviceIds.get(jid)) {
 121					SignalProtocolAddress address = new SignalProtocolAddress(jid.toString(), foreignId);
 122					if (fetchStatusMap.getAll(address.getName()).containsValue(FetchStatus.ERROR)) {
 123						return true;
 124					}
 125				}
 126			}
 127		}
 128		return false;
 129	}
 130
 131	public void preVerifyFingerprint(Contact contact, String fingerprint) {
 132		axolotlStore.preVerifyFingerprint(contact.getAccount(), contact.getJid().asBareJid().toString(), fingerprint);
 133	}
 134
 135	public void preVerifyFingerprint(Account account, String fingerprint) {
 136		axolotlStore.preVerifyFingerprint(account, account.getJid().asBareJid().toString(), fingerprint);
 137	}
 138
 139	public boolean hasVerifiedKeys(String name) {
 140		for (XmppAxolotlSession session : this.sessions.getAll(name).values()) {
 141			if (session.getTrust().isVerified()) {
 142				return true;
 143			}
 144		}
 145		return false;
 146	}
 147
 148	private static class AxolotlAddressMap<T> {
 149		protected Map<String, Map<Integer, T>> map;
 150		protected final Object MAP_LOCK = new Object();
 151
 152		public AxolotlAddressMap() {
 153			this.map = new HashMap<>();
 154		}
 155
 156		public void put(SignalProtocolAddress address, T value) {
 157			synchronized (MAP_LOCK) {
 158				Map<Integer, T> devices = map.get(address.getName());
 159				if (devices == null) {
 160					devices = new HashMap<>();
 161					map.put(address.getName(), devices);
 162				}
 163				devices.put(address.getDeviceId(), value);
 164			}
 165		}
 166
 167		public T get(SignalProtocolAddress address) {
 168			synchronized (MAP_LOCK) {
 169				Map<Integer, T> devices = map.get(address.getName());
 170				if (devices == null) {
 171					return null;
 172				}
 173				return devices.get(address.getDeviceId());
 174			}
 175		}
 176
 177		public Map<Integer, T> getAll(String name) {
 178			synchronized (MAP_LOCK) {
 179				Map<Integer, T> devices = map.get(name);
 180				if (devices == null) {
 181					return new HashMap<>();
 182				}
 183				return devices;
 184			}
 185		}
 186
 187		public boolean hasAny(SignalProtocolAddress address) {
 188			synchronized (MAP_LOCK) {
 189				Map<Integer, T> devices = map.get(address.getName());
 190				return devices != null && !devices.isEmpty();
 191			}
 192		}
 193
 194		public void clear() {
 195			map.clear();
 196		}
 197
 198	}
 199
 200	private static class SessionMap extends AxolotlAddressMap<XmppAxolotlSession> {
 201		private final XmppConnectionService xmppConnectionService;
 202		private final Account account;
 203
 204		public SessionMap(XmppConnectionService service, SQLiteAxolotlStore store, Account account) {
 205			super();
 206			this.xmppConnectionService = service;
 207			this.account = account;
 208			this.fillMap(store);
 209		}
 210
 211		public Set<Jid> findCounterpartsForSourceId(Integer sid) {
 212			Set<Jid> candidates = new HashSet<>();
 213			synchronized (MAP_LOCK) {
 214				for(Map.Entry<String,Map<Integer,XmppAxolotlSession>> entry : map.entrySet()) {
 215					String key = entry.getKey();
 216					if (entry.getValue().containsKey(sid)) {
 217						candidates.add(Jid.of(key));
 218					}
 219				}
 220			}
 221			return candidates;
 222		}
 223
 224		private void putDevicesForJid(String bareJid, List<Integer> deviceIds, SQLiteAxolotlStore store) {
 225			for (Integer deviceId : deviceIds) {
 226				SignalProtocolAddress axolotlAddress = new SignalProtocolAddress(bareJid, deviceId);
 227				IdentityKey identityKey = store.loadSession(axolotlAddress).getSessionState().getRemoteIdentityKey();
 228				if (Config.X509_VERIFICATION) {
 229					X509Certificate certificate = store.getFingerprintCertificate(CryptoHelper.bytesToHex(identityKey.getPublicKey().serialize()));
 230					if (certificate != null) {
 231						Bundle information = CryptoHelper.extractCertificateInformation(certificate);
 232						try {
 233							final String cn = information.getString("subject_cn");
 234							final Jid jid = Jid.of(bareJid);
 235							Log.d(Config.LOGTAG, "setting common name for " + jid + " to " + cn);
 236							account.getRoster().getContact(jid).setCommonName(cn);
 237						} catch (final IllegalArgumentException ignored) {
 238							//ignored
 239						}
 240					}
 241				}
 242				this.put(axolotlAddress, new XmppAxolotlSession(account, store, axolotlAddress, identityKey));
 243			}
 244		}
 245
 246		private void fillMap(SQLiteAxolotlStore store) {
 247			List<Integer> deviceIds = store.getSubDeviceSessions(account.getJid().asBareJid().toString());
 248			putDevicesForJid(account.getJid().asBareJid().toString(), deviceIds, store);
 249			for (String address : store.getKnownAddresses()) {
 250				deviceIds = store.getSubDeviceSessions(address);
 251				putDevicesForJid(address, deviceIds, store);
 252			}
 253		}
 254
 255		@Override
 256		public void put(SignalProtocolAddress address, XmppAxolotlSession value) {
 257			super.put(address, value);
 258			value.setNotFresh();
 259		}
 260
 261		public void put(XmppAxolotlSession session) {
 262			this.put(session.getRemoteAddress(), session);
 263		}
 264	}
 265
 266	public enum FetchStatus {
 267		PENDING,
 268		SUCCESS,
 269		SUCCESS_VERIFIED,
 270		TIMEOUT,
 271		SUCCESS_TRUSTED,
 272		ERROR
 273	}
 274
 275	private static class FetchStatusMap extends AxolotlAddressMap<FetchStatus> {
 276
 277		public void clearErrorFor(Jid jid) {
 278			synchronized (MAP_LOCK) {
 279				Map<Integer, FetchStatus> devices = this.map.get(jid.asBareJid().toString());
 280				if (devices == null) {
 281					return;
 282				}
 283				for (Map.Entry<Integer, FetchStatus> entry : devices.entrySet()) {
 284					if (entry.getValue() == FetchStatus.ERROR) {
 285						Log.d(Config.LOGTAG, "resetting error for " + jid.asBareJid() + "(" + entry.getKey() + ")");
 286						entry.setValue(FetchStatus.TIMEOUT);
 287					}
 288				}
 289			}
 290		}
 291	}
 292
 293	public static String getLogprefix(Account account) {
 294		return LOGPREFIX + " (" + account.getJid().asBareJid().toString() + "): ";
 295	}
 296
 297	public AxolotlService(Account account, XmppConnectionService connectionService) {
 298		if (account == null || connectionService == null) {
 299			throw new IllegalArgumentException("account and service cannot be null");
 300		}
 301		if (Security.getProvider("BC") == null) {
 302			Security.addProvider(new BouncyCastleProvider());
 303		}
 304		this.mXmppConnectionService = connectionService;
 305		this.account = account;
 306		this.axolotlStore = new SQLiteAxolotlStore(this.account, this.mXmppConnectionService);
 307		this.deviceIds = new HashMap<>();
 308		this.messageCache = new HashMap<>();
 309		this.sessions = new SessionMap(mXmppConnectionService, axolotlStore, account);
 310		this.fetchStatusMap = new FetchStatusMap();
 311		this.executor = new SerialSingleThreadExecutor("Axolotl");
 312	}
 313
 314	public String getOwnFingerprint() {
 315		return CryptoHelper.bytesToHex(axolotlStore.getIdentityKeyPair().getPublicKey().serialize());
 316	}
 317
 318	public Set<IdentityKey> getKeysWithTrust(FingerprintStatus status) {
 319		return axolotlStore.getContactKeysWithTrust(account.getJid().asBareJid().toString(), status);
 320	}
 321
 322	public Set<IdentityKey> getKeysWithTrust(FingerprintStatus status, Jid jid) {
 323		return axolotlStore.getContactKeysWithTrust(jid.asBareJid().toString(), status);
 324	}
 325
 326	public Set<IdentityKey> getKeysWithTrust(FingerprintStatus status, List<Jid> jids) {
 327		Set<IdentityKey> keys = new HashSet<>();
 328		for (Jid jid : jids) {
 329			keys.addAll(axolotlStore.getContactKeysWithTrust(jid.toString(), status));
 330		}
 331		return keys;
 332	}
 333
 334	public Set<Jid> findCounterpartsBySourceId(int sid) {
 335		return sessions.findCounterpartsForSourceId(sid);
 336	}
 337
 338	public long getNumTrustedKeys(Jid jid) {
 339		return axolotlStore.getContactNumTrustedKeys(jid.asBareJid().toString());
 340	}
 341
 342	public boolean anyTargetHasNoTrustedKeys(List<Jid> jids) {
 343		for (Jid jid : jids) {
 344			if (axolotlStore.getContactNumTrustedKeys(jid.asBareJid().toString()) == 0) {
 345				return true;
 346			}
 347		}
 348		return false;
 349	}
 350
 351	private SignalProtocolAddress getAddressForJid(Jid jid) {
 352		return new SignalProtocolAddress(jid.toString(), 0);
 353	}
 354
 355	public Collection<XmppAxolotlSession> findOwnSessions() {
 356		SignalProtocolAddress ownAddress = getAddressForJid(account.getJid().asBareJid());
 357		ArrayList<XmppAxolotlSession> s = new ArrayList<>(this.sessions.getAll(ownAddress.getName()).values());
 358		Collections.sort(s);
 359		return s;
 360	}
 361
 362
 363	public Collection<XmppAxolotlSession> findSessionsForContact(Contact contact) {
 364		SignalProtocolAddress contactAddress = getAddressForJid(contact.getJid());
 365		ArrayList<XmppAxolotlSession> s = new ArrayList<>(this.sessions.getAll(contactAddress.getName()).values());
 366		Collections.sort(s);
 367		return s;
 368	}
 369
 370	private Set<XmppAxolotlSession> findSessionsForConversation(Conversation conversation) {
 371		if (conversation.getContact().isSelf()) {
 372			//will be added in findOwnSessions()
 373			return Collections.emptySet();
 374		}
 375		HashSet<XmppAxolotlSession> sessions = new HashSet<>();
 376		for (Jid jid : conversation.getAcceptedCryptoTargets()) {
 377			sessions.addAll(this.sessions.getAll(getAddressForJid(jid).getName()).values());
 378		}
 379		return sessions;
 380	}
 381
 382	private boolean hasAny(Jid jid) {
 383		return sessions.hasAny(getAddressForJid(jid));
 384	}
 385
 386	public boolean isPepBroken() {
 387		return this.pepBroken;
 388	}
 389
 390	public void resetBrokenness() {
 391		this.pepBroken = false;
 392		this.numPublishTriesOnEmptyPep = 0;
 393		this.lastDeviceListNotificationHash = 0;
 394		this.healingAttempts.clear();
 395	}
 396
 397	public void clearErrorsInFetchStatusMap(Jid jid) {
 398		fetchStatusMap.clearErrorFor(jid);
 399		fetchDeviceListStatus.remove(jid);
 400	}
 401
 402	public void regenerateKeys(boolean wipeOther) {
 403		axolotlStore.regenerate();
 404		sessions.clear();
 405		fetchStatusMap.clear();
 406		fetchDeviceIdsMap.clear();
 407		fetchDeviceListStatus.clear();
 408		publishBundlesIfNeeded(true, wipeOther);
 409	}
 410
 411	public void destroy() {
 412		Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": destroying old axolotl service. no longer in use");
 413		mXmppConnectionService.databaseBackend.wipeAxolotlDb(account);
 414	}
 415
 416	public AxolotlService makeNew() {
 417		Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": make new axolotl service");
 418		return new AxolotlService(this.account, this.mXmppConnectionService);
 419	}
 420
 421	public int getOwnDeviceId() {
 422		return axolotlStore.getLocalRegistrationId();
 423	}
 424
 425	public SignalProtocolAddress getOwnAxolotlAddress() {
 426		return new SignalProtocolAddress(account.getJid().asBareJid().toString(), getOwnDeviceId());
 427	}
 428
 429	public Set<Integer> getOwnDeviceIds() {
 430		return this.deviceIds.get(account.getJid().asBareJid());
 431	}
 432
 433	public void registerDevices(final Jid jid, @NonNull final Set<Integer> deviceIds) {
 434		final int hash = deviceIds.hashCode();
 435		final boolean me = jid.asBareJid().equals(account.getJid().asBareJid());
 436		if (me) {
 437			if (hash != 0 && hash == this.lastDeviceListNotificationHash) {
 438				Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": ignoring duplicate own device id list");
 439				return;
 440			}
 441			this.lastDeviceListNotificationHash = hash;
 442		}
 443		boolean needsPublishing = me && !deviceIds.contains(getOwnDeviceId());
 444		if (me) {
 445			deviceIds.remove(getOwnDeviceId());
 446		}
 447		Set<Integer> expiredDevices = new HashSet<>(axolotlStore.getSubDeviceSessions(jid.asBareJid().toString()));
 448		expiredDevices.removeAll(deviceIds);
 449		for (Integer deviceId : expiredDevices) {
 450			SignalProtocolAddress address = new SignalProtocolAddress(jid.asBareJid().toString(), deviceId);
 451			XmppAxolotlSession session = sessions.get(address);
 452			if (session != null && session.getFingerprint() != null) {
 453				if (session.getTrust().isActive()) {
 454					session.setTrust(session.getTrust().toInactive());
 455				}
 456			}
 457		}
 458		Set<Integer> newDevices = new HashSet<>(deviceIds);
 459		for (Integer deviceId : newDevices) {
 460			SignalProtocolAddress address = new SignalProtocolAddress(jid.asBareJid().toString(), deviceId);
 461			XmppAxolotlSession session = sessions.get(address);
 462			if (session != null && session.getFingerprint() != null) {
 463				if (!session.getTrust().isActive()) {
 464					Log.d(Config.LOGTAG, "reactivating device with fingerprint " + session.getFingerprint());
 465					session.setTrust(session.getTrust().toActive());
 466				}
 467			}
 468		}
 469		if (me) {
 470			if (Config.OMEMO_AUTO_EXPIRY != 0) {
 471				needsPublishing |= deviceIds.removeAll(getExpiredDevices());
 472			}
 473			needsPublishing |= this.changeAccessMode.get();
 474			for (Integer deviceId : deviceIds) {
 475				SignalProtocolAddress ownDeviceAddress = new SignalProtocolAddress(jid.asBareJid().toString(), deviceId);
 476				if (sessions.get(ownDeviceAddress) == null) {
 477					FetchStatus status = fetchStatusMap.get(ownDeviceAddress);
 478					if (status == null || status == FetchStatus.TIMEOUT) {
 479						fetchStatusMap.put(ownDeviceAddress, FetchStatus.PENDING);
 480						this.buildSessionFromPEP(ownDeviceAddress);
 481					}
 482				}
 483			}
 484			if (needsPublishing) {
 485				publishOwnDeviceId(deviceIds);
 486			}
 487		}
 488		final Set<Integer> oldSet = this.deviceIds.get(jid);
 489		final boolean changed = oldSet == null || oldSet.hashCode() != hash;
 490		this.deviceIds.put(jid, deviceIds);
 491		if (changed) {
 492			mXmppConnectionService.updateConversationUi(); //update the lock icon
 493			mXmppConnectionService.keyStatusUpdated(null);
 494			if (me) {
 495				mXmppConnectionService.updateAccountUi();
 496			}
 497		} else {
 498			Log.d(Config.LOGTAG,"skipped device list update because it hasn't changed");
 499		}
 500	}
 501
 502	public void wipeOtherPepDevices() {
 503		if (pepBroken) {
 504			Log.d(Config.LOGTAG, getLogprefix(account) + "wipeOtherPepDevices called, but PEP is broken. Ignoring... ");
 505			return;
 506		}
 507		Set<Integer> deviceIds = new HashSet<>();
 508		deviceIds.add(getOwnDeviceId());
 509		publishDeviceIdsAndRefineAccessModel(deviceIds);
 510	}
 511
 512	public void distrustFingerprint(final String fingerprint) {
 513		final String fp = fingerprint.replaceAll("\\s", "");
 514		final FingerprintStatus fingerprintStatus = axolotlStore.getFingerprintStatus(fp);
 515		axolotlStore.setFingerprintStatus(fp, fingerprintStatus.toUntrusted());
 516	}
 517
 518	private void publishOwnDeviceIdIfNeeded() {
 519		if (pepBroken) {
 520			Log.d(Config.LOGTAG, getLogprefix(account) + "publishOwnDeviceIdIfNeeded called, but PEP is broken. Ignoring... ");
 521			return;
 522		}
 523		IqPacket packet = mXmppConnectionService.getIqGenerator().retrieveDeviceIds(account.getJid().asBareJid());
 524		mXmppConnectionService.sendIqPacket(account, packet, new OnIqPacketReceived() {
 525			@Override
 526			public void onIqPacketReceived(Account account, IqPacket packet) {
 527				if (packet.getType() == IqPacket.TYPE.TIMEOUT) {
 528					Log.d(Config.LOGTAG, getLogprefix(account) + "Timeout received while retrieving own Device Ids.");
 529				} else {
 530					//TODO consider calling registerDevices only after item-not-found to account for broken PEPs
 531					Element item = mXmppConnectionService.getIqParser().getItem(packet);
 532					Set<Integer> deviceIds = mXmppConnectionService.getIqParser().deviceIds(item);
 533					Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": retrieved own device list: " + deviceIds);
 534					registerDevices(account.getJid().asBareJid(), deviceIds);
 535				}
 536			}
 537		});
 538	}
 539
 540	private Set<Integer> getExpiredDevices() {
 541		Set<Integer> devices = new HashSet<>();
 542		for (XmppAxolotlSession session : findOwnSessions()) {
 543			if (session.getTrust().isActive()) {
 544				long diff = System.currentTimeMillis() - session.getTrust().getLastActivation();
 545				if (diff > Config.OMEMO_AUTO_EXPIRY) {
 546					long lastMessageDiff = System.currentTimeMillis() - mXmppConnectionService.databaseBackend.getLastTimeFingerprintUsed(account, session.getFingerprint());
 547					long hours = Math.round(lastMessageDiff / (1000 * 60.0 * 60.0));
 548					if (lastMessageDiff > Config.OMEMO_AUTO_EXPIRY) {
 549						devices.add(session.getRemoteAddress().getDeviceId());
 550						session.setTrust(session.getTrust().toInactive());
 551						Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": added own device " + session.getFingerprint() + " to list of expired devices. Last message received " + hours + " hours ago");
 552					} else {
 553						Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": own device " + session.getFingerprint() + " was active " + hours + " hours ago");
 554					}
 555				} //TODO print last activation diff
 556			}
 557		}
 558		return devices;
 559	}
 560
 561	private void publishOwnDeviceId(Set<Integer> deviceIds) {
 562		Set<Integer> deviceIdsCopy = new HashSet<>(deviceIds);
 563		Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "publishing own device ids");
 564		if (deviceIdsCopy.isEmpty()) {
 565			if (numPublishTriesOnEmptyPep >= publishTriesThreshold) {
 566				Log.w(Config.LOGTAG, getLogprefix(account) + "Own device publish attempt threshold exceeded, aborting...");
 567				pepBroken = true;
 568				return;
 569			} else {
 570				numPublishTriesOnEmptyPep++;
 571				Log.w(Config.LOGTAG, getLogprefix(account) + "Own device list empty, attempting to publish (try " + numPublishTriesOnEmptyPep + ")");
 572			}
 573		} else {
 574			numPublishTriesOnEmptyPep = 0;
 575		}
 576		deviceIdsCopy.add(getOwnDeviceId());
 577		publishDeviceIdsAndRefineAccessModel(deviceIdsCopy);
 578	}
 579
 580	private void publishDeviceIdsAndRefineAccessModel(Set<Integer> ids) {
 581		publishDeviceIdsAndRefineAccessModel(ids, true);
 582	}
 583
 584	private void publishDeviceIdsAndRefineAccessModel(final Set<Integer> ids, final boolean firstAttempt) {
 585		final Bundle publishOptions = account.getXmppConnection().getFeatures().pepPublishOptions() ? PublishOptions.openAccess() : null;
 586		IqPacket publish = mXmppConnectionService.getIqGenerator().publishDeviceIds(ids, publishOptions);
 587		mXmppConnectionService.sendIqPacket(account, publish, new OnIqPacketReceived() {
 588			@Override
 589			public void onIqPacketReceived(Account account, IqPacket packet) {
 590				final Element error = packet.getType() == IqPacket.TYPE.ERROR ? packet.findChild("error") : null;
 591				final boolean preConditionNotMet = PublishOptions.preconditionNotMet(packet);
 592				if (firstAttempt && preConditionNotMet) {
 593					Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": precondition wasn't met for device list. pushing node configuration");
 594					mXmppConnectionService.pushNodeConfiguration(account, AxolotlService.PEP_DEVICE_LIST, publishOptions, new XmppConnectionService.OnConfigurationPushed() {
 595						@Override
 596						public void onPushSucceeded() {
 597							publishDeviceIdsAndRefineAccessModel(ids, false);
 598						}
 599
 600						@Override
 601						public void onPushFailed() {
 602							publishDeviceIdsAndRefineAccessModel(ids, false);
 603						}
 604					});
 605				} else {
 606					if (AxolotlService.this.changeAccessMode.compareAndSet(true, false)) {
 607						Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": done changing access mode");
 608						account.setOption(Account.OPTION_REQUIRES_ACCESS_MODE_CHANGE, false);
 609						mXmppConnectionService.databaseBackend.updateAccount(account);
 610					}
 611					if (packet.getType() == IqPacket.TYPE.ERROR) {
 612						if (preConditionNotMet) {
 613							Log.d(Config.LOGTAG,account.getJid().asBareJid()+": device list pre condition still not met on second attempt");
 614						} else if (error != null) {
 615							pepBroken = true;
 616							Log.d(Config.LOGTAG, getLogprefix(account) + "Error received while publishing own device id" + packet.findChild("error"));
 617						}
 618
 619					}
 620				}
 621			}
 622		});
 623	}
 624
 625	public void publishDeviceVerificationAndBundle(final SignedPreKeyRecord signedPreKeyRecord,
 626	                                               final Set<PreKeyRecord> preKeyRecords,
 627	                                               final boolean announceAfter,
 628	                                               final boolean wipe) {
 629		try {
 630			IdentityKey axolotlPublicKey = axolotlStore.getIdentityKeyPair().getPublicKey();
 631			PrivateKey x509PrivateKey = KeyChain.getPrivateKey(mXmppConnectionService, account.getPrivateKeyAlias());
 632			X509Certificate[] chain = KeyChain.getCertificateChain(mXmppConnectionService, account.getPrivateKeyAlias());
 633			Signature verifier = Signature.getInstance("sha256WithRSA");
 634			verifier.initSign(x509PrivateKey, mXmppConnectionService.getRNG());
 635			verifier.update(axolotlPublicKey.serialize());
 636			byte[] signature = verifier.sign();
 637			IqPacket packet = mXmppConnectionService.getIqGenerator().publishVerification(signature, chain, getOwnDeviceId());
 638			Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + ": publish verification for device " + getOwnDeviceId());
 639			mXmppConnectionService.sendIqPacket(account, packet, new OnIqPacketReceived() {
 640				@Override
 641				public void onIqPacketReceived(final Account account, IqPacket packet) {
 642					String node = AxolotlService.PEP_VERIFICATION + ":" + getOwnDeviceId();
 643					mXmppConnectionService.pushNodeConfiguration(account, node, PublishOptions.openAccess(), new XmppConnectionService.OnConfigurationPushed() {
 644						@Override
 645						public void onPushSucceeded() {
 646							Log.d(Config.LOGTAG, getLogprefix(account) + "configured verification node to be world readable");
 647							publishDeviceBundle(signedPreKeyRecord, preKeyRecords, announceAfter, wipe);
 648						}
 649
 650						@Override
 651						public void onPushFailed() {
 652							Log.d(Config.LOGTAG, getLogprefix(account) + "unable to set access model on verification node");
 653							publishDeviceBundle(signedPreKeyRecord, preKeyRecords, announceAfter, wipe);
 654						}
 655					});
 656				}
 657			});
 658		} catch (Exception e) {
 659			e.printStackTrace();
 660		}
 661	}
 662
 663	public void publishBundlesIfNeeded(final boolean announce, final boolean wipe) {
 664		if (pepBroken) {
 665			Log.d(Config.LOGTAG, getLogprefix(account) + "publishBundlesIfNeeded called, but PEP is broken. Ignoring... ");
 666			return;
 667		}
 668
 669		if (account.getXmppConnection().getFeatures().pepPublishOptions()) {
 670			this.changeAccessMode.set(account.isOptionSet(Account.OPTION_REQUIRES_ACCESS_MODE_CHANGE));
 671		} else {
 672			if (account.setOption(Account.OPTION_REQUIRES_ACCESS_MODE_CHANGE, true)) {
 673				Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": server doesn’t support publish-options. setting for later access mode change");
 674				mXmppConnectionService.databaseBackend.updateAccount(account);
 675			}
 676		}
 677		if (this.changeAccessMode.get()) {
 678			Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": server gained publish-options capabilities. changing access model");
 679		}
 680		IqPacket packet = mXmppConnectionService.getIqGenerator().retrieveBundlesForDevice(account.getJid().asBareJid(), getOwnDeviceId());
 681		mXmppConnectionService.sendIqPacket(account, packet, new OnIqPacketReceived() {
 682			@Override
 683			public void onIqPacketReceived(Account account, IqPacket packet) {
 684
 685				if (packet.getType() == IqPacket.TYPE.TIMEOUT) {
 686					return; //ignore timeout. do nothing
 687				}
 688
 689				if (packet.getType() == IqPacket.TYPE.ERROR) {
 690					Element error = packet.findChild("error");
 691					if (error == null || !error.hasChild("item-not-found")) {
 692						pepBroken = true;
 693						Log.w(Config.LOGTAG, AxolotlService.getLogprefix(account) + "request for device bundles came back with something other than item-not-found" + packet);
 694						return;
 695					}
 696				}
 697
 698				PreKeyBundle bundle = mXmppConnectionService.getIqParser().bundle(packet);
 699				Map<Integer, ECPublicKey> keys = mXmppConnectionService.getIqParser().preKeyPublics(packet);
 700				boolean flush = false;
 701				if (bundle == null) {
 702					Log.w(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Received invalid bundle:" + packet);
 703					bundle = new PreKeyBundle(-1, -1, -1, null, -1, null, null, null);
 704					flush = true;
 705				}
 706				if (keys == null) {
 707					Log.w(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Received invalid prekeys:" + packet);
 708				}
 709				try {
 710					boolean changed = false;
 711					// Validate IdentityKey
 712					IdentityKeyPair identityKeyPair = axolotlStore.getIdentityKeyPair();
 713					if (flush || !identityKeyPair.getPublicKey().equals(bundle.getIdentityKey())) {
 714						Log.i(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Adding own IdentityKey " + identityKeyPair.getPublicKey() + " to PEP.");
 715						changed = true;
 716					}
 717
 718					// Validate signedPreKeyRecord + ID
 719					SignedPreKeyRecord signedPreKeyRecord;
 720					int numSignedPreKeys = axolotlStore.getSignedPreKeysCount();
 721					try {
 722						signedPreKeyRecord = axolotlStore.loadSignedPreKey(bundle.getSignedPreKeyId());
 723						if (flush
 724								|| !bundle.getSignedPreKey().equals(signedPreKeyRecord.getKeyPair().getPublicKey())
 725								|| !Arrays.equals(bundle.getSignedPreKeySignature(), signedPreKeyRecord.getSignature())) {
 726							Log.i(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Adding new signedPreKey with ID " + (numSignedPreKeys + 1) + " to PEP.");
 727							signedPreKeyRecord = KeyHelper.generateSignedPreKey(identityKeyPair, numSignedPreKeys + 1);
 728							axolotlStore.storeSignedPreKey(signedPreKeyRecord.getId(), signedPreKeyRecord);
 729							changed = true;
 730						}
 731					} catch (InvalidKeyIdException e) {
 732						Log.i(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Adding new signedPreKey with ID " + (numSignedPreKeys + 1) + " to PEP.");
 733						signedPreKeyRecord = KeyHelper.generateSignedPreKey(identityKeyPair, numSignedPreKeys + 1);
 734						axolotlStore.storeSignedPreKey(signedPreKeyRecord.getId(), signedPreKeyRecord);
 735						changed = true;
 736					}
 737
 738					// Validate PreKeys
 739					Set<PreKeyRecord> preKeyRecords = new HashSet<>();
 740					if (keys != null) {
 741						for (Integer id : keys.keySet()) {
 742							try {
 743								PreKeyRecord preKeyRecord = axolotlStore.loadPreKey(id);
 744								if (preKeyRecord.getKeyPair().getPublicKey().equals(keys.get(id))) {
 745									preKeyRecords.add(preKeyRecord);
 746								}
 747							} catch (InvalidKeyIdException ignored) {
 748							}
 749						}
 750					}
 751					int newKeys = NUM_KEYS_TO_PUBLISH - preKeyRecords.size();
 752					if (newKeys > 0) {
 753						List<PreKeyRecord> newRecords = KeyHelper.generatePreKeys(
 754								axolotlStore.getCurrentPreKeyId() + 1, newKeys);
 755						preKeyRecords.addAll(newRecords);
 756						for (PreKeyRecord record : newRecords) {
 757							axolotlStore.storePreKey(record.getId(), record);
 758						}
 759						changed = true;
 760						Log.i(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Adding " + newKeys + " new preKeys to PEP.");
 761					}
 762
 763
 764					if (changed || changeAccessMode.get()) {
 765						if (account.getPrivateKeyAlias() != null && Config.X509_VERIFICATION) {
 766							mXmppConnectionService.publishDisplayName(account);
 767							publishDeviceVerificationAndBundle(signedPreKeyRecord, preKeyRecords, announce, wipe);
 768						} else {
 769							publishDeviceBundle(signedPreKeyRecord, preKeyRecords, announce, wipe);
 770						}
 771					} else {
 772						Log.d(Config.LOGTAG, getLogprefix(account) + "Bundle " + getOwnDeviceId() + " in PEP was current");
 773						if (wipe) {
 774							wipeOtherPepDevices();
 775						} else if (announce) {
 776							Log.d(Config.LOGTAG, getLogprefix(account) + "Announcing device " + getOwnDeviceId());
 777							publishOwnDeviceIdIfNeeded();
 778						}
 779					}
 780				} catch (InvalidKeyException e) {
 781					Log.e(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Failed to publish bundle " + getOwnDeviceId() + ", reason: " + e.getMessage());
 782				}
 783			}
 784		});
 785	}
 786
 787	private void publishDeviceBundle(SignedPreKeyRecord signedPreKeyRecord,
 788	                                 Set<PreKeyRecord> preKeyRecords,
 789	                                 final boolean announceAfter,
 790	                                 final boolean wipe) {
 791		publishDeviceBundle(signedPreKeyRecord, preKeyRecords, announceAfter, wipe, true);
 792	}
 793
 794	private void publishDeviceBundle(final SignedPreKeyRecord signedPreKeyRecord,
 795	                                 final Set<PreKeyRecord> preKeyRecords,
 796	                                 final boolean announceAfter,
 797	                                 final boolean wipe,
 798	                                 final boolean firstAttempt) {
 799		final Bundle publishOptions = account.getXmppConnection().getFeatures().pepPublishOptions() ? PublishOptions.openAccess() : null;
 800		IqPacket publish = mXmppConnectionService.getIqGenerator().publishBundles(
 801				signedPreKeyRecord, axolotlStore.getIdentityKeyPair().getPublicKey(),
 802				preKeyRecords, getOwnDeviceId(), publishOptions);
 803		Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + ": Bundle " + getOwnDeviceId() + " in PEP not current. Publishing...");
 804		mXmppConnectionService.sendIqPacket(account, publish, new OnIqPacketReceived() {
 805			@Override
 806			public void onIqPacketReceived(final Account account, IqPacket packet) {
 807				final boolean preconditionNotMet = PublishOptions.preconditionNotMet(packet);
 808				if (firstAttempt && preconditionNotMet) {
 809					Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": precondition wasn't met for bundle. pushing node configuration");
 810					final String node = AxolotlService.PEP_BUNDLES + ":" + getOwnDeviceId();
 811					mXmppConnectionService.pushNodeConfiguration(account, node, publishOptions, new XmppConnectionService.OnConfigurationPushed() {
 812						@Override
 813						public void onPushSucceeded() {
 814							publishDeviceBundle(signedPreKeyRecord, preKeyRecords, announceAfter, wipe, false);
 815						}
 816
 817						@Override
 818						public void onPushFailed() {
 819							publishDeviceBundle(signedPreKeyRecord, preKeyRecords, announceAfter, wipe, false);
 820						}
 821					});
 822				} else if (packet.getType() == IqPacket.TYPE.RESULT) {
 823					Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Successfully published bundle. ");
 824					if (wipe) {
 825						wipeOtherPepDevices();
 826					} else if (announceAfter) {
 827						Log.d(Config.LOGTAG, getLogprefix(account) + "Announcing device " + getOwnDeviceId());
 828						publishOwnDeviceIdIfNeeded();
 829					}
 830				} else if (packet.getType() == IqPacket.TYPE.ERROR) {
 831					if (preconditionNotMet) {
 832						Log.d(Config.LOGTAG,getLogprefix(account) + "bundle precondition still not met after second attempt");
 833					} else {
 834						Log.d(Config.LOGTAG, getLogprefix(account) + "Error received while publishing bundle: " + packet.toString());
 835					}
 836					pepBroken = true;
 837				}
 838			}
 839		});
 840	}
 841
 842	public void deleteOmemoIdentity() {
 843		final String node = AxolotlService.PEP_BUNDLES + ":" + getOwnDeviceId();
 844		final IqPacket deleteBundleNode = mXmppConnectionService.getIqGenerator().deleteNode(node);
 845		mXmppConnectionService.sendIqPacket(account, deleteBundleNode, null);
 846		final Set<Integer> ownDeviceIds = getOwnDeviceIds();
 847		publishDeviceIdsAndRefineAccessModel(ownDeviceIds == null ? Collections.emptySet() : ownDeviceIds);
 848	}
 849
 850	public List<Jid> getCryptoTargets(Conversation conversation) {
 851		final List<Jid> jids;
 852		if (conversation.getMode() == Conversation.MODE_SINGLE) {
 853			jids = new ArrayList<>();
 854			jids.add(conversation.getJid().asBareJid());
 855		} else {
 856			jids = conversation.getMucOptions().getMembers(false);
 857		}
 858		return jids;
 859	}
 860
 861	public FingerprintStatus getFingerprintTrust(String fingerprint) {
 862		return axolotlStore.getFingerprintStatus(fingerprint);
 863	}
 864
 865	public X509Certificate getFingerprintCertificate(String fingerprint) {
 866		return axolotlStore.getFingerprintCertificate(fingerprint);
 867	}
 868
 869	public void setFingerprintTrust(String fingerprint, FingerprintStatus status) {
 870		axolotlStore.setFingerprintStatus(fingerprint, status);
 871	}
 872
 873	private void verifySessionWithPEP(final XmppAxolotlSession session) {
 874		Log.d(Config.LOGTAG, "trying to verify fresh session (" + session.getRemoteAddress().getName() + ") with pep");
 875		final SignalProtocolAddress address = session.getRemoteAddress();
 876		final IdentityKey identityKey = session.getIdentityKey();
 877		try {
 878			IqPacket packet = mXmppConnectionService.getIqGenerator().retrieveVerificationForDevice(Jid.of(address.getName()), address.getDeviceId());
 879			mXmppConnectionService.sendIqPacket(account, packet, new OnIqPacketReceived() {
 880				@Override
 881				public void onIqPacketReceived(Account account, IqPacket packet) {
 882					Pair<X509Certificate[], byte[]> verification = mXmppConnectionService.getIqParser().verification(packet);
 883					if (verification != null) {
 884						try {
 885							Signature verifier = Signature.getInstance("sha256WithRSA");
 886							verifier.initVerify(verification.first[0]);
 887							verifier.update(identityKey.serialize());
 888							if (verifier.verify(verification.second)) {
 889								try {
 890									mXmppConnectionService.getMemorizingTrustManager().getNonInteractive().checkClientTrusted(verification.first, "RSA");
 891									String fingerprint = session.getFingerprint();
 892									Log.d(Config.LOGTAG, "verified session with x.509 signature. fingerprint was: " + fingerprint);
 893									setFingerprintTrust(fingerprint, FingerprintStatus.createActiveVerified(true));
 894									axolotlStore.setFingerprintCertificate(fingerprint, verification.first[0]);
 895									fetchStatusMap.put(address, FetchStatus.SUCCESS_VERIFIED);
 896									Bundle information = CryptoHelper.extractCertificateInformation(verification.first[0]);
 897									try {
 898										final String cn = information.getString("subject_cn");
 899										final Jid jid = Jid.of(address.getName());
 900										Log.d(Config.LOGTAG, "setting common name for " + jid + " to " + cn);
 901										account.getRoster().getContact(jid).setCommonName(cn);
 902									} catch (final IllegalArgumentException ignored) {
 903										//ignored
 904									}
 905									finishBuildingSessionsFromPEP(address);
 906									return;
 907								} catch (Exception e) {
 908									Log.d(Config.LOGTAG, "could not verify certificate");
 909								}
 910							}
 911						} catch (Exception e) {
 912							Log.d(Config.LOGTAG, "error during verification " + e.getMessage());
 913						}
 914					} else {
 915						Log.d(Config.LOGTAG, "no verification found");
 916					}
 917					fetchStatusMap.put(address, FetchStatus.SUCCESS);
 918					finishBuildingSessionsFromPEP(address);
 919				}
 920			});
 921		} catch (IllegalArgumentException e) {
 922			fetchStatusMap.put(address, FetchStatus.SUCCESS);
 923			finishBuildingSessionsFromPEP(address);
 924		}
 925	}
 926
 927	private final Set<Integer> PREVIOUSLY_REMOVED_FROM_ANNOUNCEMENT = new HashSet<>();
 928
 929	private void finishBuildingSessionsFromPEP(final SignalProtocolAddress address) {
 930		SignalProtocolAddress ownAddress = new SignalProtocolAddress(account.getJid().asBareJid().toString(), 0);
 931		Map<Integer, FetchStatus> own = fetchStatusMap.getAll(ownAddress.getName());
 932		Map<Integer, FetchStatus> remote = fetchStatusMap.getAll(address.getName());
 933		if (!own.containsValue(FetchStatus.PENDING) && !remote.containsValue(FetchStatus.PENDING)) {
 934			FetchStatus report = null;
 935			if (own.containsValue(FetchStatus.SUCCESS) || remote.containsValue(FetchStatus.SUCCESS)) {
 936				report = FetchStatus.SUCCESS;
 937			} else if (own.containsValue(FetchStatus.SUCCESS_VERIFIED) || remote.containsValue(FetchStatus.SUCCESS_VERIFIED)) {
 938				report = FetchStatus.SUCCESS_VERIFIED;
 939			} else if (own.containsValue(FetchStatus.SUCCESS_TRUSTED) || remote.containsValue(FetchStatus.SUCCESS_TRUSTED)) {
 940				report = FetchStatus.SUCCESS_TRUSTED;
 941			} else if (own.containsValue(FetchStatus.ERROR) || remote.containsValue(FetchStatus.ERROR)) {
 942				report = FetchStatus.ERROR;
 943			}
 944			mXmppConnectionService.keyStatusUpdated(report);
 945		}
 946		if (Config.REMOVE_BROKEN_DEVICES) {
 947			Set<Integer> ownDeviceIds = new HashSet<>(getOwnDeviceIds());
 948			boolean publish = false;
 949			for (Map.Entry<Integer, FetchStatus> entry : own.entrySet()) {
 950				int id = entry.getKey();
 951				if (entry.getValue() == FetchStatus.ERROR && PREVIOUSLY_REMOVED_FROM_ANNOUNCEMENT.add(id) && ownDeviceIds.remove(id)) {
 952					publish = true;
 953					Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": error fetching own device with id " + id + ". removing from announcement");
 954				}
 955			}
 956			if (publish) {
 957				publishOwnDeviceId(ownDeviceIds);
 958			}
 959		}
 960	}
 961
 962	public boolean hasEmptyDeviceList(Jid jid) {
 963		return !hasAny(jid) && (!deviceIds.containsKey(jid) || deviceIds.get(jid).isEmpty());
 964	}
 965
 966	public interface OnDeviceIdsFetched {
 967		void fetched(Jid jid, Set<Integer> deviceIds);
 968	}
 969
 970	public interface OnMultipleDeviceIdFetched {
 971		void fetched();
 972	}
 973
 974	public void fetchDeviceIds(final Jid jid) {
 975		fetchDeviceIds(jid, null);
 976	}
 977
 978	private void fetchDeviceIds(final Jid jid, OnDeviceIdsFetched callback) {
 979		IqPacket packet;
 980		synchronized (this.fetchDeviceIdsMap) {
 981			List<OnDeviceIdsFetched> callbacks = this.fetchDeviceIdsMap.get(jid);
 982			if (callbacks != null) {
 983				if (callback != null) {
 984					callbacks.add(callback);
 985				}
 986				Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": fetching device ids for " + jid + " already running. adding callback");
 987				packet = null;
 988			} else {
 989				callbacks = new ArrayList<>();
 990				if (callback != null) {
 991					callbacks.add(callback);
 992				}
 993				this.fetchDeviceIdsMap.put(jid, callbacks);
 994				Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": fetching device ids for " + jid);
 995				packet = mXmppConnectionService.getIqGenerator().retrieveDeviceIds(jid);
 996			}
 997		}
 998		if (packet != null) {
 999			mXmppConnectionService.sendIqPacket(account, packet, (account, response) -> {
1000				if (response.getType() == IqPacket.TYPE.RESULT) {
1001					fetchDeviceListStatus.put(jid, true);
1002					Element item = mXmppConnectionService.getIqParser().getItem(response);
1003					Set<Integer> deviceIds = mXmppConnectionService.getIqParser().deviceIds(item);
1004					registerDevices(jid, deviceIds);
1005					final List<OnDeviceIdsFetched> callbacks;
1006					synchronized (fetchDeviceIdsMap) {
1007						callbacks = fetchDeviceIdsMap.remove(jid);
1008					}
1009					if (callbacks != null) {
1010						for (OnDeviceIdsFetched c : callbacks) {
1011							c.fetched(jid, deviceIds);
1012						}
1013					}
1014				} else {
1015					if (response.getType() == IqPacket.TYPE.TIMEOUT) {
1016						fetchDeviceListStatus.remove(jid);
1017					} else {
1018						fetchDeviceListStatus.put(jid, false);
1019					}
1020					final List<OnDeviceIdsFetched> callbacks;
1021					synchronized (fetchDeviceIdsMap) {
1022						callbacks = fetchDeviceIdsMap.remove(jid);
1023					}
1024					if (callbacks != null) {
1025						for (OnDeviceIdsFetched c : callbacks) {
1026							c.fetched(jid, null);
1027						}
1028					}
1029				}
1030			});
1031		}
1032	}
1033
1034	private void fetchDeviceIds(List<Jid> jids, final OnMultipleDeviceIdFetched callback) {
1035		final ArrayList<Jid> unfinishedJids = new ArrayList<>(jids);
1036		synchronized (unfinishedJids) {
1037			for (Jid jid : unfinishedJids) {
1038				fetchDeviceIds(jid, (j, deviceIds) -> {
1039					synchronized (unfinishedJids) {
1040						unfinishedJids.remove(j);
1041						if (unfinishedJids.size() == 0 && callback != null) {
1042							callback.fetched();
1043						}
1044					}
1045				});
1046			}
1047		}
1048	}
1049
1050	interface OnSessionBuildFromPep {
1051		void onSessionBuildSuccessful();
1052		void onSessionBuildFailed();
1053	}
1054
1055	private void buildSessionFromPEP(final SignalProtocolAddress address) {
1056		buildSessionFromPEP(address, null);
1057	}
1058
1059	private void buildSessionFromPEP(final SignalProtocolAddress address, OnSessionBuildFromPep callback) {
1060		Log.i(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Building new session for " + address.toString());
1061		if (address.equals(getOwnAxolotlAddress())) {
1062			throw new AssertionError("We should NEVER build a session with ourselves. What happened here?!");
1063		}
1064
1065		final Jid jid = Jid.of(address.getName());
1066		final boolean oneOfOurs = jid.asBareJid().equals(account.getJid().asBareJid());
1067		IqPacket bundlesPacket = mXmppConnectionService.getIqGenerator().retrieveBundlesForDevice(jid, address.getDeviceId());
1068		mXmppConnectionService.sendIqPacket(account, bundlesPacket, (account, packet) -> {
1069			if (packet.getType() == IqPacket.TYPE.TIMEOUT) {
1070				fetchStatusMap.put(address, FetchStatus.TIMEOUT);
1071			} else if (packet.getType() == IqPacket.TYPE.RESULT) {
1072				Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Received preKey IQ packet, processing...");
1073				final IqParser parser = mXmppConnectionService.getIqParser();
1074				final List<PreKeyBundle> preKeyBundleList = parser.preKeys(packet);
1075				final PreKeyBundle bundle = parser.bundle(packet);
1076				if (preKeyBundleList.isEmpty() || bundle == null) {
1077					Log.e(Config.LOGTAG, AxolotlService.getLogprefix(account) + "preKey IQ packet invalid: " + packet);
1078					fetchStatusMap.put(address, FetchStatus.ERROR);
1079					finishBuildingSessionsFromPEP(address);
1080					if (callback != null) {
1081						callback.onSessionBuildFailed();
1082					}
1083					return;
1084				}
1085				Random random = new Random();
1086				final PreKeyBundle preKey = preKeyBundleList.get(random.nextInt(preKeyBundleList.size()));
1087				if (preKey == null) {
1088					//should never happen
1089					fetchStatusMap.put(address, FetchStatus.ERROR);
1090					finishBuildingSessionsFromPEP(address);
1091					if (callback != null) {
1092						callback.onSessionBuildFailed();
1093					}
1094					return;
1095				}
1096
1097				final PreKeyBundle preKeyBundle = new PreKeyBundle(0, address.getDeviceId(),
1098						preKey.getPreKeyId(), preKey.getPreKey(),
1099						bundle.getSignedPreKeyId(), bundle.getSignedPreKey(),
1100						bundle.getSignedPreKeySignature(), bundle.getIdentityKey());
1101
1102				try {
1103					SessionBuilder builder = new SessionBuilder(axolotlStore, address);
1104					builder.process(preKeyBundle);
1105					XmppAxolotlSession session = new XmppAxolotlSession(account, axolotlStore, address, bundle.getIdentityKey());
1106					sessions.put(address, session);
1107					if (Config.X509_VERIFICATION) {
1108						verifySessionWithPEP(session); //TODO; maybe inject callback in here too
1109					} else {
1110						FingerprintStatus status = getFingerprintTrust(CryptoHelper.bytesToHex(bundle.getIdentityKey().getPublicKey().serialize()));
1111						FetchStatus fetchStatus;
1112						if (status != null && status.isVerified()) {
1113							fetchStatus = FetchStatus.SUCCESS_VERIFIED;
1114						} else if (status != null && status.isTrusted()) {
1115							fetchStatus = FetchStatus.SUCCESS_TRUSTED;
1116						} else {
1117							fetchStatus = FetchStatus.SUCCESS;
1118						}
1119						fetchStatusMap.put(address, fetchStatus);
1120						finishBuildingSessionsFromPEP(address);
1121						if (callback != null) {
1122							callback.onSessionBuildSuccessful();
1123						}
1124					}
1125				} catch (UntrustedIdentityException | InvalidKeyException e) {
1126					Log.e(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Error building session for " + address + ": "
1127							+ e.getClass().getName() + ", " + e.getMessage());
1128					fetchStatusMap.put(address, FetchStatus.ERROR);
1129					finishBuildingSessionsFromPEP(address);
1130					if (oneOfOurs && cleanedOwnDeviceIds.add(address.getDeviceId())) {
1131						removeFromDeviceAnnouncement(address.getDeviceId());
1132					}
1133					if (callback != null) {
1134						callback.onSessionBuildFailed();
1135					}
1136				}
1137			} else {
1138				fetchStatusMap.put(address, FetchStatus.ERROR);
1139				Element error = packet.findChild("error");
1140				boolean itemNotFound = error != null && error.hasChild("item-not-found");
1141				Log.d(Config.LOGTAG, getLogprefix(account) + "Error received while building session:" + packet.findChild("error"));
1142				finishBuildingSessionsFromPEP(address);
1143				if (oneOfOurs && itemNotFound && cleanedOwnDeviceIds.add(address.getDeviceId())) {
1144					removeFromDeviceAnnouncement(address.getDeviceId());
1145				}
1146				if (callback != null) {
1147					callback.onSessionBuildFailed();
1148				}
1149			}
1150		});
1151	}
1152
1153	private void removeFromDeviceAnnouncement(Integer id) {
1154		HashSet<Integer> temp = new HashSet<>(getOwnDeviceIds());
1155		if (temp.remove(id)) {
1156			Log.d(Config.LOGTAG,account.getJid().asBareJid()+" remove own device id "+id+" from announcement. devices left:"+temp);
1157			publishOwnDeviceId(temp);
1158		}
1159	}
1160
1161	public Set<SignalProtocolAddress> findDevicesWithoutSession(final Conversation conversation) {
1162		Set<SignalProtocolAddress> addresses = new HashSet<>();
1163		for (Jid jid : getCryptoTargets(conversation)) {
1164			Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Finding devices without session for " + jid);
1165			final Set<Integer> ids = deviceIds.get(jid);
1166			if (ids != null && !ids.isEmpty()) {
1167				for (Integer foreignId : ids) {
1168					SignalProtocolAddress address = new SignalProtocolAddress(jid.toString(), foreignId);
1169					if (sessions.get(address) == null) {
1170						IdentityKey identityKey = axolotlStore.loadSession(address).getSessionState().getRemoteIdentityKey();
1171						if (identityKey != null) {
1172							Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Already have session for " + address.toString() + ", adding to cache...");
1173							XmppAxolotlSession session = new XmppAxolotlSession(account, axolotlStore, address, identityKey);
1174							sessions.put(address, session);
1175						} else {
1176							Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Found device " + jid + ":" + foreignId);
1177							if (fetchStatusMap.get(address) != FetchStatus.ERROR) {
1178								addresses.add(address);
1179							} else {
1180								Log.d(Config.LOGTAG, getLogprefix(account) + "skipping over " + address + " because it's broken");
1181							}
1182						}
1183					}
1184				}
1185			} else {
1186				mXmppConnectionService.keyStatusUpdated(FetchStatus.ERROR);
1187				Log.w(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Have no target devices in PEP!");
1188			}
1189		}
1190		Set<Integer> ownIds = this.deviceIds.get(account.getJid().asBareJid());
1191		for (Integer ownId : (ownIds != null ? ownIds : new HashSet<Integer>())) {
1192			SignalProtocolAddress address = new SignalProtocolAddress(account.getJid().asBareJid().toString(), ownId);
1193			if (sessions.get(address) == null) {
1194				IdentityKey identityKey = axolotlStore.loadSession(address).getSessionState().getRemoteIdentityKey();
1195				if (identityKey != null) {
1196					Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Already have session for " + address.toString() + ", adding to cache...");
1197					XmppAxolotlSession session = new XmppAxolotlSession(account, axolotlStore, address, identityKey);
1198					sessions.put(address, session);
1199				} else {
1200					Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Found device " + account.getJid().asBareJid() + ":" + ownId);
1201					if (fetchStatusMap.get(address) != FetchStatus.ERROR) {
1202						addresses.add(address);
1203					} else {
1204						Log.d(Config.LOGTAG, getLogprefix(account) + "skipping over " + address + " because it's broken");
1205					}
1206				}
1207			}
1208		}
1209
1210		return addresses;
1211	}
1212
1213	public boolean createSessionsIfNeeded(final Conversation conversation) {
1214		final List<Jid> jidsWithEmptyDeviceList = getCryptoTargets(conversation);
1215		for (Iterator<Jid> iterator = jidsWithEmptyDeviceList.iterator(); iterator.hasNext(); ) {
1216			final Jid jid = iterator.next();
1217			if (!hasEmptyDeviceList(jid)) {
1218				iterator.remove();
1219			}
1220		}
1221		Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": createSessionsIfNeeded() - jids with empty device list: " + jidsWithEmptyDeviceList);
1222		if (jidsWithEmptyDeviceList.size() > 0) {
1223			fetchDeviceIds(jidsWithEmptyDeviceList, () -> createSessionsIfNeededActual(conversation));
1224			return true;
1225		} else {
1226			return createSessionsIfNeededActual(conversation);
1227		}
1228	}
1229
1230	private boolean createSessionsIfNeededActual(final Conversation conversation) {
1231		Log.i(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Creating axolotl sessions if needed...");
1232		boolean newSessions = false;
1233		Set<SignalProtocolAddress> addresses = findDevicesWithoutSession(conversation);
1234		for (SignalProtocolAddress address : addresses) {
1235			Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Processing device: " + address.toString());
1236			FetchStatus status = fetchStatusMap.get(address);
1237			if (status == null || status == FetchStatus.TIMEOUT) {
1238				fetchStatusMap.put(address, FetchStatus.PENDING);
1239				this.buildSessionFromPEP(address);
1240				newSessions = true;
1241			} else if (status == FetchStatus.PENDING) {
1242				newSessions = true;
1243			} else {
1244				Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Already fetching bundle for " + address.toString());
1245			}
1246		}
1247
1248		return newSessions;
1249	}
1250
1251	public boolean trustedSessionVerified(final Conversation conversation) {
1252		final Set<XmppAxolotlSession> sessions = new HashSet<>();
1253		sessions.addAll(findSessionsForConversation(conversation));
1254		sessions.addAll(findOwnSessions());
1255		boolean verified = false;
1256		for (XmppAxolotlSession session : sessions) {
1257			if (session.getTrust().isTrustedAndActive()) {
1258				if (session.getTrust().getTrust() == FingerprintStatus.Trust.VERIFIED_X509) {
1259					verified = true;
1260				} else {
1261					return false;
1262				}
1263			}
1264		}
1265		return verified;
1266	}
1267
1268	public boolean hasPendingKeyFetches(List<Jid> jids) {
1269		SignalProtocolAddress ownAddress = new SignalProtocolAddress(account.getJid().asBareJid().toString(), 0);
1270		if (fetchStatusMap.getAll(ownAddress.getName()).containsValue(FetchStatus.PENDING)) {
1271			return true;
1272		}
1273		synchronized (this.fetchDeviceIdsMap) {
1274			for (Jid jid : jids) {
1275				SignalProtocolAddress foreignAddress = new SignalProtocolAddress(jid.asBareJid().toString(), 0);
1276				if (fetchStatusMap.getAll(foreignAddress.getName()).containsValue(FetchStatus.PENDING) || this.fetchDeviceIdsMap.containsKey(jid)) {
1277					return true;
1278				}
1279			}
1280		}
1281		return false;
1282	}
1283
1284	@Nullable
1285	private boolean buildHeader(XmppAxolotlMessage axolotlMessage, Conversation c) {
1286		Set<XmppAxolotlSession> remoteSessions = findSessionsForConversation(c);
1287		final boolean acceptEmpty = (c.getMode() == Conversation.MODE_MULTI && c.getMucOptions().getUserCount() == 0) || c.getContact().isSelf();
1288		Collection<XmppAxolotlSession> ownSessions = findOwnSessions();
1289		if (remoteSessions.isEmpty() && !acceptEmpty) {
1290			return false;
1291		}
1292		for (XmppAxolotlSession session : remoteSessions) {
1293			axolotlMessage.addDevice(session);
1294		}
1295		for (XmppAxolotlSession session : ownSessions) {
1296			axolotlMessage.addDevice(session);
1297		}
1298
1299		return true;
1300	}
1301
1302	//this is being used for private muc messages only
1303	private boolean buildHeader(XmppAxolotlMessage axolotlMessage, Jid jid) {
1304		if (jid == null) {
1305			return false;
1306		}
1307		HashSet<XmppAxolotlSession> sessions = new HashSet<>();
1308		sessions.addAll(this.sessions.getAll(getAddressForJid(jid).getName()).values());
1309		if (sessions.isEmpty()) {
1310			return false;
1311		}
1312		sessions.addAll(findOwnSessions());
1313		for(XmppAxolotlSession session : sessions) {
1314			axolotlMessage.addDevice(session);
1315		}
1316		return true;
1317	}
1318
1319	@Nullable
1320	public XmppAxolotlMessage encrypt(Message message) {
1321		final XmppAxolotlMessage axolotlMessage = new XmppAxolotlMessage(account.getJid().asBareJid(), getOwnDeviceId());
1322		final String content;
1323		if (message.hasFileOnRemoteHost()) {
1324			content = message.getFileParams().url.toString();
1325		} else {
1326			content = message.getBody();
1327		}
1328		try {
1329			axolotlMessage.encrypt(content);
1330		} catch (CryptoFailedException e) {
1331			Log.w(Config.LOGTAG, getLogprefix(account) + "Failed to encrypt message: " + e.getMessage());
1332			return null;
1333		}
1334
1335		final boolean success;
1336		if (message.isPrivateMessage()) {
1337			success = buildHeader(axolotlMessage, message.getTrueCounterpart());
1338		} else {
1339			success = buildHeader(axolotlMessage, (Conversation) message.getConversation());
1340		}
1341		return success ? axolotlMessage : null;
1342	}
1343
1344	public void preparePayloadMessage(final Message message, final boolean delay) {
1345		executor.execute(new Runnable() {
1346			@Override
1347			public void run() {
1348				XmppAxolotlMessage axolotlMessage = encrypt(message);
1349				if (axolotlMessage == null) {
1350					mXmppConnectionService.markMessage(message, Message.STATUS_SEND_FAILED);
1351					//mXmppConnectionService.updateConversationUi();
1352				} else {
1353					Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Generated message, caching: " + message.getUuid());
1354					messageCache.put(message.getUuid(), axolotlMessage);
1355					mXmppConnectionService.resendMessage(message, delay);
1356				}
1357			}
1358		});
1359	}
1360
1361	public void prepareKeyTransportMessage(final Conversation conversation, final OnMessageCreatedCallback onMessageCreatedCallback) {
1362		executor.execute(new Runnable() {
1363			@Override
1364			public void run() {
1365				final XmppAxolotlMessage axolotlMessage = new XmppAxolotlMessage(account.getJid().asBareJid(), getOwnDeviceId());
1366				if (buildHeader(axolotlMessage, conversation)) {
1367					onMessageCreatedCallback.run(axolotlMessage);
1368				} else {
1369					onMessageCreatedCallback.run(null);
1370				}
1371			}
1372		});
1373	}
1374
1375	public XmppAxolotlMessage fetchAxolotlMessageFromCache(Message message) {
1376		XmppAxolotlMessage axolotlMessage = messageCache.get(message.getUuid());
1377		if (axolotlMessage != null) {
1378			Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Cache hit: " + message.getUuid());
1379			messageCache.remove(message.getUuid());
1380		} else {
1381			Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Cache miss: " + message.getUuid());
1382		}
1383		return axolotlMessage;
1384	}
1385
1386	private XmppAxolotlSession recreateUncachedSession(SignalProtocolAddress address) {
1387		IdentityKey identityKey = axolotlStore.loadSession(address).getSessionState().getRemoteIdentityKey();
1388		return (identityKey != null)
1389				? new XmppAxolotlSession(account, axolotlStore, address, identityKey)
1390				: null;
1391	}
1392
1393	private XmppAxolotlSession getReceivingSession(XmppAxolotlMessage message) {
1394		SignalProtocolAddress senderAddress = new SignalProtocolAddress(message.getFrom().toString(), message.getSenderDeviceId());
1395		return getReceivingSession(senderAddress);
1396
1397	}
1398
1399	private XmppAxolotlSession getReceivingSession(SignalProtocolAddress senderAddress) {
1400		XmppAxolotlSession session = sessions.get(senderAddress);
1401		if (session == null) {
1402			//Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Account: " + account.getJid() + " No axolotl session found while parsing received message " + message);
1403			session = recreateUncachedSession(senderAddress);
1404			if (session == null) {
1405				session = new XmppAxolotlSession(account, axolotlStore, senderAddress);
1406			}
1407		}
1408		return session;
1409	}
1410
1411	public XmppAxolotlMessage.XmppAxolotlPlaintextMessage processReceivingPayloadMessage(XmppAxolotlMessage message, boolean postponePreKeyMessageHandling) throws NotEncryptedForThisDeviceException, BrokenSessionException {
1412		XmppAxolotlMessage.XmppAxolotlPlaintextMessage plaintextMessage = null;
1413
1414		XmppAxolotlSession session = getReceivingSession(message);
1415		int ownDeviceId = getOwnDeviceId();
1416		try {
1417			plaintextMessage = message.decrypt(session, ownDeviceId);
1418			Integer preKeyId = session.getPreKeyIdAndReset();
1419			if (preKeyId != null) {
1420				postPreKeyMessageHandling(session, postponePreKeyMessageHandling);
1421			}
1422		} catch (NotEncryptedForThisDeviceException e) {
1423			if (account.getJid().asBareJid().equals(message.getFrom().asBareJid()) && message.getSenderDeviceId() == ownDeviceId) {
1424				Log.w(Config.LOGTAG, getLogprefix(account) + "Reflected omemo message received");
1425			} else {
1426				throw e;
1427			}
1428		} catch (final BrokenSessionException e) {
1429			throw e;
1430		} catch (CryptoFailedException e) {
1431			Log.w(Config.LOGTAG, getLogprefix(account) + "Failed to decrypt message from " + message.getFrom(), e);
1432		}
1433
1434		if (session.isFresh() && plaintextMessage != null) {
1435			putFreshSession(session);
1436		}
1437
1438		return plaintextMessage;
1439	}
1440
1441	public void reportBrokenSessionException(BrokenSessionException e, boolean postpone) {
1442		Log.e(Config.LOGTAG,account.getJid().asBareJid()+": broken session with "+e.getSignalProtocolAddress().toString()+" detected", e);
1443		if (postpone) {
1444			postponedHealing.add(e.getSignalProtocolAddress());
1445		} else {
1446			notifyRequiresHealing(e.getSignalProtocolAddress());
1447		}
1448	}
1449
1450	private void notifyRequiresHealing(final SignalProtocolAddress signalProtocolAddress) {
1451		if (healingAttempts.add(signalProtocolAddress)) {
1452			Log.d(Config.LOGTAG,account.getJid().asBareJid()+": attempt to heal "+signalProtocolAddress);
1453			buildSessionFromPEP(signalProtocolAddress, new OnSessionBuildFromPep() {
1454				@Override
1455				public void onSessionBuildSuccessful() {
1456					Log.d(Config.LOGTAG, "successfully build new session from pep after detecting broken session");
1457					completeSession(getReceivingSession(signalProtocolAddress));
1458				}
1459
1460				@Override
1461				public void onSessionBuildFailed() {
1462					Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": unable to build new session from pep after detecting broken session");
1463				}
1464			});
1465		} else {
1466			Log.d(Config.LOGTAG,account.getJid().asBareJid()+": do not attempt to heal "+signalProtocolAddress+" again");
1467		}
1468	}
1469
1470	private void postPreKeyMessageHandling(final XmppAxolotlSession session, final boolean postpone) {
1471		if (postpone) {
1472			postponedSessions.add(session);
1473		} else {
1474			if (axolotlStore.flushPreKeys()) {
1475				publishBundlesIfNeeded(false, false);
1476			} else {
1477				Log.d(Config.LOGTAG,account.getJid().asBareJid()+": nothing to flush. Not republishing key");
1478			}
1479			if (trustedOrPreviouslyResponded(session)) {
1480				completeSession(session);
1481			}
1482		}
1483	}
1484
1485	public void processPostponed() {
1486		if (postponedSessions.size() > 0) {
1487			if (axolotlStore.flushPreKeys()) {
1488				publishBundlesIfNeeded(false, false);
1489			}
1490		}
1491		final Iterator<XmppAxolotlSession> iterator = postponedSessions.iterator();
1492		while (iterator.hasNext()) {
1493			final XmppAxolotlSession session = iterator.next();
1494			if (trustedOrPreviouslyResponded(session)) {
1495				completeSession(session);
1496			}
1497			iterator.remove();
1498		}
1499		final Iterator<SignalProtocolAddress> postponedHealingAttemptsIterator = postponedHealing.iterator();
1500		while (postponedHealingAttemptsIterator.hasNext()) {
1501			notifyRequiresHealing(postponedHealingAttemptsIterator.next());
1502			postponedHealingAttemptsIterator.remove();
1503		}
1504	}
1505
1506
1507	private boolean trustedOrPreviouslyResponded(XmppAxolotlSession session) {
1508		try {
1509			return trustedOrPreviouslyResponded(Jid.of(session.getRemoteAddress().getName()));
1510		} catch (IllegalArgumentException e) {
1511			return false;
1512		}
1513	}
1514
1515	public boolean trustedOrPreviouslyResponded(Jid jid) {
1516		final Contact contact = account.getRoster().getContact(jid);
1517		if (contact.showInRoster() || contact.isSelf()) {
1518			return true;
1519		}
1520		final Conversation conversation = mXmppConnectionService.find(account, jid);
1521		return conversation != null && conversation.sentMessagesCount() > 0;
1522	}
1523
1524	private void completeSession(XmppAxolotlSession session) {
1525		final XmppAxolotlMessage axolotlMessage = new XmppAxolotlMessage(account.getJid().asBareJid(), getOwnDeviceId());
1526		axolotlMessage.addDevice(session, true);
1527		try {
1528			final Jid jid = Jid.of(session.getRemoteAddress().getName());
1529			MessagePacket packet = mXmppConnectionService.getMessageGenerator().generateKeyTransportMessage(jid, axolotlMessage);
1530			mXmppConnectionService.sendMessagePacket(account, packet);
1531		} catch (IllegalArgumentException e) {
1532			throw new Error("Remote addresses are created from jid and should convert back to jid", e);
1533		}
1534	}
1535
1536
1537	public XmppAxolotlMessage.XmppAxolotlKeyTransportMessage processReceivingKeyTransportMessage(XmppAxolotlMessage message, final boolean postponePreKeyMessageHandling) {
1538		final XmppAxolotlMessage.XmppAxolotlKeyTransportMessage keyTransportMessage;
1539		final XmppAxolotlSession session = getReceivingSession(message);
1540		try {
1541			keyTransportMessage = message.getParameters(session, getOwnDeviceId());
1542			Integer preKeyId = session.getPreKeyIdAndReset();
1543			if (preKeyId != null) {
1544				postPreKeyMessageHandling(session, postponePreKeyMessageHandling);
1545			}
1546		} catch (CryptoFailedException e) {
1547			Log.d(Config.LOGTAG, "could not decrypt keyTransport message " + e.getMessage());
1548			return null;
1549		}
1550
1551		if (session.isFresh() && keyTransportMessage != null) {
1552			putFreshSession(session);
1553		}
1554
1555		return keyTransportMessage;
1556	}
1557
1558	private void putFreshSession(XmppAxolotlSession session) {
1559		sessions.put(session);
1560		if (Config.X509_VERIFICATION) {
1561			if (session.getIdentityKey() != null) {
1562				verifySessionWithPEP(session);
1563			} else {
1564				Log.e(Config.LOGTAG, account.getJid().asBareJid() + ": identity key was empty after reloading for x509 verification");
1565			}
1566		}
1567	}
1568}