lnpeer: reestablish_channel - discard unsigned remote updates

electrum/lnhtlc.py

@@ -167,6 +167,25 @@ class HTLCManager:
             if fee_update.ctns[LOCAL] is None and fee_update.ctns[REMOTE] <= self.ctn_latest(REMOTE):
                 fee_update.ctns[LOCAL] = self.ctn_latest(LOCAL) + 1
 
+    def discard_unsigned_remote_updates(self):
+        """Discard updates sent by the remote, that the remote itself
+        did not yet sign (i.e. there was no corresponding commitment_signed msg)
+        """
+        # htlcs
+        for htlc_id, ctns in list(self.log[REMOTE]['locked_in'].items()):
+            if ctns[LOCAL] > self.ctn_latest(LOCAL):
+                del self.log[REMOTE]['locked_in'][htlc_id]
+                del self.log[REMOTE]['adds'][htlc_id]
+        self.log[REMOTE]['next_htlc_id'] = max(self.log[REMOTE]['locked_in']) + 1
+        for log_action in ('settles', 'fails'):
+            for htlc_id, ctns in list(self.log[LOCAL][log_action].items()):
+                if ctns[LOCAL] > self.ctn_latest(LOCAL):
+                    del self.log[LOCAL][log_action][htlc_id]
+        # fee updates
+        for i, fee_update in enumerate(list(self.log[REMOTE]['fee_updates'])):
+            if fee_update.ctns[LOCAL] > self.ctn_latest(LOCAL):
+                del self.log[REMOTE]['fee_updates'][i]
+
     ##### Queries re HTLCs:
 
     def htlcs_by_direction(self, subject: HTLCOwner, direction: Direction,

electrum/lnpeer.py

@@ -692,6 +692,8 @@ class Peer(Logger):
             return
         chan.set_state('REESTABLISHING')
         self.network.trigger_callback('channel', chan)
+        # BOLT-02: "A node [...] upon disconnection [...] MUST reverse any uncommitted updates sent by the other side"
+        chan.hm.discard_unsigned_remote_updates()
         # ctns
         oldest_unrevoked_local_ctn = chan.config[LOCAL].ctn
         latest_local_ctn = chan.hm.ctn_latest(LOCAL)