implement self healing omemo

after receiving a SignalMessage that can’t be decrypted because of broken sessions
Conversations will attempt to grab a new pre key bundle and send a new PreKeySignalMessage
wrapped in a key transport message.
This commit is contained in:
Daniel Gultsch 2018-12-02 14:41:25 +01:00
parent f1e1c4a78d
commit c02676ea4c
13 changed files with 160 additions and 37 deletions

View File

@ -82,9 +82,11 @@ public class AxolotlService implements OnAdvancedStreamFeaturesLoaded {
private final SerialSingleThreadExecutor executor;
private int numPublishTriesOnEmptyPep = 0;
private boolean pepBroken = false;
private final Set<SignalProtocolAddress> healingAttempts = new HashSet<>();
private int lastDeviceListNotificationHash = 0;
private final HashSet<Integer> cleanedOwnDeviceIds = new HashSet<>();
private Set<XmppAxolotlSession> postponedSessions = new HashSet<>(); //sessions stored here will receive after mam catchup treatment
private Set<SignalProtocolAddress> postponedHealing = new HashSet<>(); //addresses stored here will need a healing notification after mam catchup
private AtomicBoolean changeAccessMode = new AtomicBoolean(false);
@ -390,6 +392,7 @@ public class AxolotlService implements OnAdvancedStreamFeaturesLoaded {
this.pepBroken = false;
this.numPublishTriesOnEmptyPep = 0;
this.lastDeviceListNotificationHash = 0;
this.healingAttempts.clear();
}
public void clearErrorsInFetchStatusMap(Jid jid) {
@ -1071,7 +1074,16 @@ public class AxolotlService implements OnAdvancedStreamFeaturesLoaded {
}
}
interface OnSessionBuildFromPep {
void onSessionBuildSuccessful();
void onSessionBuildFailed();
}
private void buildSessionFromPEP(final SignalProtocolAddress address) {
buildSessionFromPEP(address, null);
}
private void buildSessionFromPEP(final SignalProtocolAddress address, OnSessionBuildFromPep callback) {
Log.i(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Building new session for " + address.toString());
if (address.equals(getOwnAxolotlAddress())) {
throw new AssertionError("We should NEVER build a session with ourselves. What happened here?!");
@ -1092,6 +1104,9 @@ public class AxolotlService implements OnAdvancedStreamFeaturesLoaded {
Log.e(Config.LOGTAG, AxolotlService.getLogprefix(account) + "preKey IQ packet invalid: " + packet);
fetchStatusMap.put(address, FetchStatus.ERROR);
finishBuildingSessionsFromPEP(address);
if (callback != null) {
callback.onSessionBuildFailed();
}
return;
}
Random random = new Random();
@ -1100,6 +1115,9 @@ public class AxolotlService implements OnAdvancedStreamFeaturesLoaded {
//should never happen
fetchStatusMap.put(address, FetchStatus.ERROR);
finishBuildingSessionsFromPEP(address);
if (callback != null) {
callback.onSessionBuildFailed();
}
return;
}
@ -1114,7 +1132,7 @@ public class AxolotlService implements OnAdvancedStreamFeaturesLoaded {
XmppAxolotlSession session = new XmppAxolotlSession(account, axolotlStore, address, bundle.getIdentityKey());
sessions.put(address, session);
if (Config.X509_VERIFICATION) {
verifySessionWithPEP(session);
verifySessionWithPEP(session); //TODO; maybe inject callback in here too
} else {
FingerprintStatus status = getFingerprintTrust(CryptoHelper.bytesToHex(bundle.getIdentityKey().getPublicKey().serialize()));
FetchStatus fetchStatus;
@ -1127,6 +1145,9 @@ public class AxolotlService implements OnAdvancedStreamFeaturesLoaded {
}
fetchStatusMap.put(address, fetchStatus);
finishBuildingSessionsFromPEP(address);
if (callback != null) {
callback.onSessionBuildSuccessful();
}
}
} catch (UntrustedIdentityException | InvalidKeyException e) {
Log.e(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Error building session for " + address + ": "
@ -1136,6 +1157,9 @@ public class AxolotlService implements OnAdvancedStreamFeaturesLoaded {
if (oneOfOurs && cleanedOwnDeviceIds.add(address.getDeviceId())) {
removeFromDeviceAnnouncement(address.getDeviceId());
}
if (callback != null) {
callback.onSessionBuildFailed();
}
}
} else {
fetchStatusMap.put(address, FetchStatus.ERROR);
@ -1146,6 +1170,9 @@ public class AxolotlService implements OnAdvancedStreamFeaturesLoaded {
if (oneOfOurs && itemNotFound && cleanedOwnDeviceIds.add(address.getDeviceId())) {
removeFromDeviceAnnouncement(address.getDeviceId());
}
if (callback != null) {
callback.onSessionBuildFailed();
}
}
});
}
@ -1391,11 +1418,15 @@ public class AxolotlService implements OnAdvancedStreamFeaturesLoaded {
}
private XmppAxolotlSession getReceivingSession(XmppAxolotlMessage message) {
SignalProtocolAddress senderAddress = new SignalProtocolAddress(message.getFrom().toString(),
message.getSenderDeviceId());
SignalProtocolAddress senderAddress = new SignalProtocolAddress(message.getFrom().toString(), message.getSenderDeviceId());
return getReceivingSession(senderAddress);
}
private XmppAxolotlSession getReceivingSession(SignalProtocolAddress senderAddress) {
XmppAxolotlSession session = sessions.get(senderAddress);
if (session == null) {
Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Account: " + account.getJid() + " No axolotl session found while parsing received message " + message);
//Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Account: " + account.getJid() + " No axolotl session found while parsing received message " + message);
session = recreateUncachedSession(senderAddress);
if (session == null) {
session = new XmppAxolotlSession(account, axolotlStore, senderAddress);
@ -1404,7 +1435,7 @@ public class AxolotlService implements OnAdvancedStreamFeaturesLoaded {
return session;
}
public XmppAxolotlMessage.XmppAxolotlPlaintextMessage processReceivingPayloadMessage(XmppAxolotlMessage message, boolean postponePreKeyMessageHandling) throws NotEncryptedForThisDeviceException {
public XmppAxolotlMessage.XmppAxolotlPlaintextMessage processReceivingPayloadMessage(XmppAxolotlMessage message, boolean postponePreKeyMessageHandling) throws NotEncryptedForThisDeviceException, BrokenSessionException {
XmppAxolotlMessage.XmppAxolotlPlaintextMessage plaintextMessage = null;
XmppAxolotlSession session = getReceivingSession(message);
@ -1421,8 +1452,10 @@ public class AxolotlService implements OnAdvancedStreamFeaturesLoaded {
} else {
throw e;
}
} catch (final BrokenSessionException e) {
throw e;
} catch (CryptoFailedException e) {
Log.w(Config.LOGTAG, getLogprefix(account) + "Failed to decrypt message from " + message.getFrom() + ": " + e.getMessage());
Log.w(Config.LOGTAG, getLogprefix(account) + "Failed to decrypt message from " + message.getFrom(), e);
}
if (session.isFresh() && plaintextMessage != null) {
@ -1432,6 +1465,35 @@ public class AxolotlService implements OnAdvancedStreamFeaturesLoaded {
return plaintextMessage;
}
public void reportBrokenSessionException(BrokenSessionException e, boolean postpone) {
Log.e(Config.LOGTAG,account.getJid().asBareJid()+": broken session with "+e.getSignalProtocolAddress().toString()+" detected", e);
if (postpone) {
postponedHealing.add(e.getSignalProtocolAddress());
} else {
notifyRequiresHealing(e.getSignalProtocolAddress());
}
}
private void notifyRequiresHealing(final SignalProtocolAddress signalProtocolAddress) {
if (healingAttempts.add(signalProtocolAddress)) {
Log.d(Config.LOGTAG,account.getJid().asBareJid()+": attempt to heal "+signalProtocolAddress);
buildSessionFromPEP(signalProtocolAddress, new OnSessionBuildFromPep() {
@Override
public void onSessionBuildSuccessful() {
Log.d(Config.LOGTAG, "successfully build new session from pep after detecting broken session");
completeSession(getReceivingSession(signalProtocolAddress));
}
@Override
public void onSessionBuildFailed() {
Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": unable to build new session from pep after detecting broken session");
}
});
} else {
Log.d(Config.LOGTAG,account.getJid().asBareJid()+": do not attempt to heal "+signalProtocolAddress+" again");
}
}
private void postPreKeyMessageHandling(final XmppAxolotlSession session, int preKeyId, final boolean postpone) {
if (postpone) {
postponedSessions.add(session);
@ -1451,6 +1513,11 @@ public class AxolotlService implements OnAdvancedStreamFeaturesLoaded {
completeSession(iterator.next());
iterator.remove();
}
Iterator<SignalProtocolAddress> postponedHealingAttemptsIterator = postponedHealing.iterator();
while (postponedHealingAttemptsIterator.hasNext()) {
notifyRequiresHealing(postponedHealingAttemptsIterator.next());
postponedHealingAttemptsIterator.remove();
}
}
private void completeSession(XmppAxolotlSession session) {

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@ -0,0 +1,18 @@
package eu.siacs.conversations.crypto.axolotl;
import org.whispersystems.libsignal.SignalProtocolAddress;
public class BrokenSessionException extends CryptoFailedException {
private final SignalProtocolAddress signalProtocolAddress;
public BrokenSessionException(SignalProtocolAddress address, Exception e) {
super(e);
this.signalProtocolAddress = address;
}
public SignalProtocolAddress getSignalProtocolAddress() {
return signalProtocolAddress;
}
}

View File

@ -6,6 +6,10 @@ public class CryptoFailedException extends Exception {
super(msg);
}
public CryptoFailedException(String msg, Exception e) {
super(msg, e);
}
public CryptoFailedException(Exception e){
super(e);
}

View File

@ -79,34 +79,35 @@ public class XmppAxolotlSession implements Comparable<XmppAxolotlSession> {
}
@Nullable
public byte[] processReceiving(AxolotlKey encryptedKey) throws CryptoFailedException {
byte[] processReceiving(AxolotlKey encryptedKey) throws CryptoFailedException {
byte[] plaintext;
FingerprintStatus status = getTrust();
if (!status.isCompromised()) {
try {
if (encryptedKey.prekey) {
PreKeySignalMessage preKeySignalMessage = new PreKeySignalMessage(encryptedKey.key);
Optional<Integer> optionalPreKeyId = preKeySignalMessage.getPreKeyId();
IdentityKey identityKey = preKeySignalMessage.getIdentityKey();
if (!optionalPreKeyId.isPresent()) {
throw new CryptoFailedException("PreKeyWhisperMessage did not contain a PreKeyId");
}
preKeyId = optionalPreKeyId.get();
if (this.identityKey != null && !this.identityKey.equals(identityKey)) {
throw new CryptoFailedException("Received PreKeyWhisperMessage but preexisting identity key changed.");
}
this.identityKey = identityKey;
plaintext = cipher.decrypt(preKeySignalMessage);
} else {
SignalMessage signalMessage = new SignalMessage(encryptedKey.key);
plaintext = cipher.decrypt(signalMessage);
preKeyId = null; //better safe than sorry because we use that to do special after prekey handling
}
} catch (InvalidVersionException | InvalidKeyException | LegacyMessageException | InvalidMessageException | DuplicateMessageException | NoSessionException | InvalidKeyIdException | UntrustedIdentityException e) {
if (!(e instanceof DuplicateMessageException)) {
e.printStackTrace();
}
throw new CryptoFailedException("Error decrypting WhisperMessage " + e.getClass().getSimpleName() + ": " + e.getMessage());
if (encryptedKey.prekey) {
PreKeySignalMessage preKeySignalMessage = new PreKeySignalMessage(encryptedKey.key);
Optional<Integer> optionalPreKeyId = preKeySignalMessage.getPreKeyId();
IdentityKey identityKey = preKeySignalMessage.getIdentityKey();
if (!optionalPreKeyId.isPresent()) {
throw new CryptoFailedException("PreKeyWhisperMessage did not contain a PreKeyId");
}
preKeyId = optionalPreKeyId.get();
if (this.identityKey != null && !this.identityKey.equals(identityKey)) {
throw new CryptoFailedException("Received PreKeyWhisperMessage but preexisting identity key changed.");
}
this.identityKey = identityKey;
plaintext = cipher.decrypt(preKeySignalMessage);
} else {
SignalMessage signalMessage = new SignalMessage(encryptedKey.key);
try {
plaintext = cipher.decrypt(signalMessage);
} catch (InvalidMessageException | NoSessionException e) {
throw new BrokenSessionException(this.remoteAddress, e);
}
preKeyId = null; //better safe than sorry because we use that to do special after prekey handling
}
} catch (InvalidVersionException | InvalidKeyException | LegacyMessageException | InvalidMessageException | DuplicateMessageException | InvalidKeyIdException | UntrustedIdentityException e) {
throw new CryptoFailedException("Error decrypting SignalMessage", e);
}
if (!status.isActive()) {
setTrust(status.toActive());

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@ -702,6 +702,20 @@ public class Conversation extends AbstractEntity implements Blockable, Comparabl
}
}
public boolean possibleDuplicate(final String serverMsgId, final String remoteMsgId) {
if (serverMsgId == null || remoteMsgId == null) {
return false;
}
synchronized (this.messages) {
for(Message message : this.messages) {
if (serverMsgId.equals(message.getServerMsgId()) || remoteMsgId.equals(message.getRemoteMsgId())) {
return true;
}
}
}
return false;
}
public MamReference getLastMessageTransmitted() {
final MamReference lastClear = getLastClearHistory();
MamReference lastReceived = new MamReference(0);

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@ -47,6 +47,7 @@ public class Message extends AbstractEntity {
public static final int ENCRYPTION_DECRYPTION_FAILED = 4;
public static final int ENCRYPTION_AXOLOTL = 5;
public static final int ENCRYPTION_AXOLOTL_NOT_FOR_THIS_DEVICE = 6;
public static final int ENCRYPTION_AXOLOTL_FAILED = 7;
public static final int TYPE_TEXT = 0;
public static final int TYPE_IMAGE = 1;
@ -883,7 +884,7 @@ public class Message extends AbstractEntity {
if (encryption == ENCRYPTION_DECRYPTED || encryption == ENCRYPTION_DECRYPTION_FAILED) {
return ENCRYPTION_PGP;
}
if (encryption == ENCRYPTION_AXOLOTL_NOT_FOR_THIS_DEVICE) {
if (encryption == ENCRYPTION_AXOLOTL_NOT_FOR_THIS_DEVICE || encryption == ENCRYPTION_AXOLOTL_FAILED) {
return ENCRYPTION_AXOLOTL;
}
return encryption;

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@ -16,6 +16,7 @@ import java.util.UUID;
import eu.siacs.conversations.Config;
import eu.siacs.conversations.R;
import eu.siacs.conversations.crypto.axolotl.AxolotlService;
import eu.siacs.conversations.crypto.axolotl.BrokenSessionException;
import eu.siacs.conversations.crypto.axolotl.NotEncryptedForThisDeviceException;
import eu.siacs.conversations.crypto.axolotl.XmppAxolotlMessage;
import eu.siacs.conversations.entities.Account;
@ -107,7 +108,7 @@ public class MessageParser extends AbstractParser implements OnMessagePacketRece
return false;
}
private Message parseAxolotlChat(Element axolotlMessage, Jid from, Conversation conversation, int status, boolean postpone) {
private Message parseAxolotlChat(Element axolotlMessage, Jid from, Conversation conversation, int status, boolean checkedForDuplicates, boolean postpone) {
final AxolotlService service = conversation.getAccount().getAxolotlService();
final XmppAxolotlMessage xmppAxolotlMessage;
try {
@ -120,6 +121,14 @@ public class MessageParser extends AbstractParser implements OnMessagePacketRece
final XmppAxolotlMessage.XmppAxolotlPlaintextMessage plaintextMessage;
try {
plaintextMessage = service.processReceivingPayloadMessage(xmppAxolotlMessage, postpone);
} catch (BrokenSessionException e) {
if (checkedForDuplicates) {
service.reportBrokenSessionException(e, postpone);
return new Message(conversation, "", Message.ENCRYPTION_AXOLOTL_FAILED, status);
} else {
Log.d(Config.LOGTAG,"ignoring broken session exception because checkForDuplicase failed");
return null;
}
} catch (NotEncryptedForThisDeviceException e) {
return new Message(conversation, "", Message.ENCRYPTION_AXOLOTL_NOT_FOR_THIS_DEVICE, status);
}
@ -424,12 +433,15 @@ public class MessageParser extends AbstractParser implements OnMessagePacketRece
fallbacksBySourceId = Collections.emptySet();
origin = from;
}
final boolean checkedForDuplicates = serverMsgId != null && remoteMsgId != null && !conversation.possibleDuplicate(serverMsgId, remoteMsgId);
if (origin != null) {
message = parseAxolotlChat(axolotlEncrypted, origin, conversation, status, query != null);
message = parseAxolotlChat(axolotlEncrypted, origin, conversation, status, checkedForDuplicates,query != null);
} else {
Message trial = null;
for (Jid fallback : fallbacksBySourceId) {
trial = parseAxolotlChat(axolotlEncrypted, fallback, conversation, status, query != null);
trial = parseAxolotlChat(axolotlEncrypted, fallback, conversation, status, checkedForDuplicates && fallbacksBySourceId.size() == 1, query != null);
if (trial != null) {
Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": decoded muc message using fallback");
origin = fallback;
@ -606,7 +618,7 @@ public class MessageParser extends AbstractParser implements OnMessagePacketRece
if (message.getEncryption() == Message.ENCRYPTION_PGP) {
notify = conversation.getAccount().getPgpDecryptionService().decrypt(message, notify);
} else if (message.getEncryption() == Message.ENCRYPTION_AXOLOTL_NOT_FOR_THIS_DEVICE) {
} else if (message.getEncryption() == Message.ENCRYPTION_AXOLOTL_NOT_FOR_THIS_DEVICE || message.getEncryption() == Message.ENCRYPTION_AXOLOTL_FAILED) {
notify = false;
}

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@ -751,7 +751,7 @@ public class DatabaseBackend extends SQLiteOpenHelper {
public Cursor getMessageSearchCursor(List<String> term) {
SQLiteDatabase db = this.getReadableDatabase();
String SQL = "SELECT " + Message.TABLENAME + ".*," + Conversation.TABLENAME + '.' + Conversation.CONTACTJID + ',' + Conversation.TABLENAME + '.' + Conversation.ACCOUNT + ',' + Conversation.TABLENAME + '.' + Conversation.MODE + " FROM " + Message.TABLENAME + " join " + Conversation.TABLENAME + " on " + Message.TABLENAME + '.' + Message.CONVERSATION + '=' + Conversation.TABLENAME + '.' + Conversation.UUID + " join messages_index ON messages_index.uuid=messages.uuid where " + Message.ENCRYPTION + " NOT IN(" + Message.ENCRYPTION_AXOLOTL_NOT_FOR_THIS_DEVICE + ',' + Message.ENCRYPTION_PGP + ',' + Message.ENCRYPTION_DECRYPTION_FAILED + ") AND " + Message.TYPE + " IN(" + Message.TYPE_TEXT + ',' + Message.TYPE_PRIVATE + ") AND messages_index.body MATCH ? ORDER BY " + Message.TIME_SENT + " DESC limit " + Config.MAX_SEARCH_RESULTS;
String SQL = "SELECT " + Message.TABLENAME + ".*," + Conversation.TABLENAME + '.' + Conversation.CONTACTJID + ',' + Conversation.TABLENAME + '.' + Conversation.ACCOUNT + ',' + Conversation.TABLENAME + '.' + Conversation.MODE + " FROM " + Message.TABLENAME + " join " + Conversation.TABLENAME + " on " + Message.TABLENAME + '.' + Message.CONVERSATION + '=' + Conversation.TABLENAME + '.' + Conversation.UUID + " join messages_index ON messages_index.uuid=messages.uuid where " + Message.ENCRYPTION + " NOT IN(" + Message.ENCRYPTION_AXOLOTL_NOT_FOR_THIS_DEVICE + ',' + Message.ENCRYPTION_PGP + ',' + Message.ENCRYPTION_DECRYPTION_FAILED + ','+Message.ENCRYPTION_AXOLOTL_FAILED+") AND " + Message.TYPE + " IN(" + Message.TYPE_TEXT + ',' + Message.TYPE_PRIVATE + ") AND messages_index.body MATCH ? ORDER BY " + Message.TIME_SENT + " DESC limit " + Config.MAX_SEARCH_RESULTS;
Log.d(Config.LOGTAG, "search term: " + FtsUtils.toMatchString(term));
return db.rawQuery(SQL, new String[]{FtsUtils.toMatchString(term)});
}

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@ -1096,7 +1096,7 @@ public class ConversationFragment extends XmppFragment implements EditMessage.Ke
}
if (m.getType() != Message.TYPE_STATUS) {
if (m.getEncryption() == Message.ENCRYPTION_AXOLOTL_NOT_FOR_THIS_DEVICE) {
if (m.getEncryption() == Message.ENCRYPTION_AXOLOTL_NOT_FOR_THIS_DEVICE || m.getEncryption() == Message.ENCRYPTION_AXOLOTL_FAILED) {
return;
}

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@ -775,6 +775,8 @@ public class MessageAdapter extends ArrayAdapter<Message> implements CopyTextVie
displayInfoMessage(viewHolder, activity.getString(R.string.decryption_failed), darkBackground);
} else if (message.getEncryption() == Message.ENCRYPTION_AXOLOTL_NOT_FOR_THIS_DEVICE) {
displayInfoMessage(viewHolder, activity.getString(R.string.not_encrypted_for_this_device), darkBackground);
} else if (message.getEncryption() == Message.ENCRYPTION_AXOLOTL_FAILED) {
displayInfoMessage(viewHolder, activity.getString(R.string.omemo_decryption_failed), darkBackground);
} else {
if (message.isGeoUri()) {
displayLocationMessage(viewHolder, message);

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@ -264,6 +264,7 @@ public final class CryptoHelper {
return R.string.encryption_choice_otr;
case Message.ENCRYPTION_AXOLOTL:
case Message.ENCRYPTION_AXOLOTL_NOT_FOR_THIS_DEVICE:
case Message.ENCRYPTION_AXOLOTL_FAILED:
return R.string.encryption_choice_omemo;
case Message.ENCRYPTION_NONE:
return R.string.encryption_choice_unencrypted;

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@ -292,6 +292,8 @@ public class UIHelper {
return new Pair<>(context.getString(R.string.decryption_failed), true);
} else if (message.getEncryption() == Message.ENCRYPTION_AXOLOTL_NOT_FOR_THIS_DEVICE) {
return new Pair<>(context.getString(R.string.not_encrypted_for_this_device), true);
} else if (message.getEncryption() == Message.ENCRYPTION_AXOLOTL_FAILED) {
return new Pair<>(context.getString(R.string.omemo_decryption_failed), true);
} else if (message.getType() == Message.TYPE_FILE || message.getType() == Message.TYPE_IMAGE) {
return new Pair<>(getFileDescriptionString(context, message), true);
} else {

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@ -697,6 +697,7 @@
<string name="medium">Medium</string>
<string name="large">Large</string>
<string name="not_encrypted_for_this_device">Message was not encrypted for this device.</string>
<string name="omemo_decryption_failed">Failed to decrypt OMEMO message.</string>
<string name="undo">undo</string>
<string name="location_disabled">Location sharing is disabled</string>
<string name="action_fix_to_location">Fix position</string>