Discard deferred Noise ciphertext during panic

bitchat/Services/BLE/BLENoisePacketHandler.swift

@@ -184,6 +184,16 @@ final class BLENoisePacketHandler {
         drainDeferredCiphertextsIfReady(for: peerID)
     }
 
+    /// Synchronously discards ciphertext retained for a pre-panic Noise
+    /// generation. The handler survives the service's identity replacement,
+    /// so keeping this queue would replay old bytes after post-panic auth.
+    func resetForPanic() {
+        deferredLock.lock()
+        deferredCiphertexts.removeAll(keepingCapacity: false)
+        deferredCiphertextBytes = 0
+        deferredLock.unlock()
+    }
+
     private func handleEncrypted(
         _ packet: BitchatPacket,
         from peerID: PeerID,

bitchat/Services/BLE/BLEService.swift

@@ -718,6 +718,7 @@ final class BLEService: NSObject {
     /// or advertising while the full panic transaction is incomplete.
     func suspendForPanicReset() {
         setPanicSuspended(true)
+        noisePacketHandler.resetForPanic()
         gossipSyncManager?.stop()
         gossipSyncManager = nil
         // Stop the radio and drain CoreBluetooth's delegate queue first. A
@@ -728,7 +729,11 @@ final class BLEService: NSObject {
         // Drain every receive/send submitted by callbacks that finished ahead
         // of the radio stop. Later callbacks observe the closed lifecycle, and
         // generation-bound handoffs that raced this barrier reject themselves.
-        messageQueue.sync(flags: .barrier) {}
+        // Clear the old identity's bounded early-ciphertext queue again after
+        // those callbacks drain so none can repopulate it after the first wipe.
+        messageQueue.sync(flags: .barrier) {
+            noisePacketHandler.resetForPanic()
+        }
         clearEmergencySessionState()
     }
 
@@ -746,6 +751,11 @@ final class BLEService: NSObject {
     ) {
         gossipSyncManager?.stop()
         gossipSyncManager = nil
+        // Discard deferred pre-panic ciphertext behind any in-flight receive
+        // handlers so none can repopulate the handler's bounded queue.
+        messageQueue.sync(flags: .barrier) {
+            noisePacketHandler.resetForPanic()
+        }
         // pendingNoiseSessionQueues is owned by collectionsQueue everywhere
         // else, so clear it there too rather than on messageQueue.
         collectionsQueue.sync(flags: .barrier) {

bitchatTests/Services/BLENoisePacketHandlerTests.swift

@@ -521,6 +521,60 @@ struct BLENoisePacketHandlerTests {
         #expect(recorder.initiatedHandshakes.isEmpty)
     }
 
+    @Test
+    func panicResetDiscardsDeferredCiphertextBeforeFutureAuthentication() {
+        let recorder = Recorder()
+        recorder.hasSession = true
+        recorder.awaitingResponderHandshake = true
+        recorder.decryptResult = .failure(
+            CryptoKitError.authenticationFailure
+        )
+        let handler = makeHandler(recorder: recorder)
+        let prePanicCiphertext = makeEncryptedPacket(
+            recipientID: Data(hexString: localPeerID.id),
+            payload: Data(
+                count: NoiseSecurityConstants.maxMessageSize
+                    + NoiseSecurityConstants.transportCiphertextOverhead
+            )
+        )
+
+        handler.handleEncrypted(prePanicCiphertext, from: remotePeerID)
+        #expect(recorder.decryptCalls.count == 1)
+
+        handler.resetForPanic()
+
+        // Three maximum-sized packets fit only when reset also zeroed the
+        // global byte accounting. They model ciphertext received under the
+        // replacement identity before that responder handshake completes.
+        for index in 0..<3 {
+            handler.handleEncrypted(
+                makeEncryptedPacket(
+                    recipientID: Data(hexString: localPeerID.id),
+                    timestamp: UInt64(901_000 + index),
+                    payload: Data(
+                        count: NoiseSecurityConstants.maxMessageSize
+                            + NoiseSecurityConstants.transportCiphertextOverhead
+                    )
+                ),
+                from: remotePeerID
+            )
+        }
+        #expect(recorder.decryptCalls.count == 4)
+
+        recorder.awaitingResponderHandshake = false
+        recorder.decryptResult = .success(
+            Data([NoisePayloadType.privateMessage.rawValue, 0xCA, 0xFE])
+        )
+        handler.handleSessionAuthenticated(remotePeerID)
+
+        // Only the three post-reset packets replay; the pre-panic packet does
+        // not survive into the replacement session.
+        #expect(recorder.decryptCalls.count == 7)
+        #expect(recorder.deliveries.count == 3)
+        #expect(recorder.clearedSessions.isEmpty)
+        #expect(recorder.initiatedHandshakes.isEmpty)
+    }
+
     @Test
     func ciphertextQueuedAheadOfEstablishmentCallbackDoesNotConsumeNonce()
         throws {