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.

1 files changed, 16 insertions, 4 deletions

diff --git a/src/main/java/de/pixart/messenger/parser/MessageParser.java b/src/main/java/de/pixart/messenger/parser/MessageParser.java
index ed12d6473..8f5b1b851 100644
--- a/src/main/java/de/pixart/messenger/parser/MessageParser.java
+++ b/src/main/java/de/pixart/messenger/parser/MessageParser.java
@@ -23,6 +23,7 @@ import de.pixart.messenger.Config;
 import de.pixart.messenger.R;
 import de.pixart.messenger.crypto.OtrService;
 import de.pixart.messenger.crypto.axolotl.AxolotlService;
+import de.pixart.messenger.crypto.axolotl.BrokenSessionException;
 import de.pixart.messenger.crypto.axolotl.NotEncryptedForThisDeviceException;
 import de.pixart.messenger.crypto.axolotl.XmppAxolotlMessage;
 import de.pixart.messenger.entities.Account;
@@ -200,7 +201,7 @@ public class MessageParser extends AbstractParser implements OnMessagePacketRece
         }
     }
 
-    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 {
@@ -213,6 +214,14 @@ 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);
             }
@@ -531,12 +540,15 @@ 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;
@@ -713,7 +725,7 @@ 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;
             }