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