Stabilize synchronous Noise restart tests

bitchat/Noise/NoiseSecurityConstants.swift

@@ -36,6 +36,30 @@ enum NoiseSecurityConstants {
 
     // Noise XX message 1 contains only the initiator's 32-byte ephemeral key.
     static let xxInitialMessageSize = 32
+
+    // Bounds an ordinary initiator whose message 1 or 2 is lost.
+    static let ordinaryHandshakeTimeout: TimeInterval = 10
+
+    // Bounds the receive-only rollback quarantine created by an unauthenticated
+    // inbound message 1. A lost message 3 must not strand outbound traffic.
+    static let ordinaryResponderHandshakeTimeout: TimeInterval = 20
+
+    // A released client may immediately retry after both crossed initiators
+    // yielded. Give that unilateral retry a brief head start before the
+    // patched side spends its one bounded recovery.
+    static let handshakeCollisionRecoveryDelay: TimeInterval = 0.2
+
+    // Rate-limited recovery remains actionable without spinning.
+    static let handshakeRateLimitRecoveryDelay: TimeInterval = 60
+
+    // Covers only reordering between a winning message 3 and the losing
+    // crossed message 1.
+    static let recentInitiatorCompletionGracePeriod: TimeInterval = 1
+
+    // After unauthenticated responder rollback, reject another attempt long
+    // enough that paced message 1 traffic cannot keep outbound paused. A
+    // legitimate peer converges through the one manager-owned local retry.
+    static let ordinaryReconnectRollbackCooldown: TimeInterval = 60
     
     // Session timeout - sessions older than this should be renegotiated
     static let sessionTimeout: TimeInterval = 86400 // 24 hours

bitchat/Noise/NoiseSessionError.swift

@@ -13,3 +13,9 @@ enum NoiseSessionError: Error, Equatable {
     case alreadyEstablished
     case peerIdentityMismatch
 }
+
+/// The manager owns the exact attempt's one bounded recovery. Packet handling
+/// must not launch its historical second, immediate restart for this failure.
+struct NoiseManagedHandshakeFailure: Error {
+    let underlying: Error
+}

bitchat/Services/BLE/BLENoisePacketHandler.swift

@@ -62,8 +62,8 @@ final class BLENoisePacketHandler {
     }
 
     /// Returns true when the handshake message was processed successfully.
-    /// Callers use this to distinguish an authenticated replacement completion
-    /// from a rejected candidate while an older session remains established.
+    /// Callers use this to distinguish an authenticated reconnect completion
+    /// from a rejected ordinary responder while rollback state is restored.
     @discardableResult
     func handleHandshake(_ packet: BitchatPacket, from peerID: PeerID) -> Bool {
         let env = environment
@@ -89,8 +89,13 @@ final class BLENoisePacketHandler {
                 // Session establishment will trigger onPeerAuthenticated callback
                 // which will send any pending messages at the right time
                 return true
+            } catch let managedFailure as NoiseManagedHandshakeFailure {
+                SecureLogger.error(
+                    "Failed to process handshake; manager owns recovery: \(managedFailure.underlying)"
+                )
+                return false
             } catch NoiseSessionError.peerIdentityMismatch {
-                // The candidate was already discarded by the session manager.
+                // The responder was already discarded by the session manager.
                 // Do not let a spoofed claimed ID trigger a fresh outbound
                 // handshake or recreate state for the attacker-selected ID.
                 SecureLogger.warning(

bitchat/Services/BLE/BLENoiseReconnectPolicy.swift

@@ -0,0 +1,40 @@
+import Foundation
+
+/// Bounds ordinary Noise revalidation to one attempt per physical-link epoch.
+/// A live epoch may retry after the cooldown so a lost handshake cannot leave
+/// the link permanently unauthenticated.
+struct BLENoiseReconnectPolicy {
+    static let minimumRetryInterval: TimeInterval = 60
+
+    private var lastAttemptAt: [BLEIngressLinkID: Date] = [:]
+
+    mutating func shouldRevalidate(
+        on link: BLEIngressLinkID,
+        hasEstablishedSession: Bool,
+        isNoiseAuthenticatedLink: Bool,
+        hasAuthenticatedPeerLink: Bool,
+        now: Date
+    ) -> Bool {
+        guard hasEstablishedSession,
+              !isNoiseAuthenticatedLink,
+              !hasAuthenticatedPeerLink else {
+            return false
+        }
+        if let previous = lastAttemptAt[link],
+           now.timeIntervalSince(previous) < Self.minimumRetryInterval {
+            return false
+        }
+        lastAttemptAt[link] = now
+        return true
+    }
+
+    /// Link identifiers can be stable across CoreBluetooth reconnects, so a
+    /// disconnect explicitly starts a new epoch and permits one fresh attempt.
+    mutating func endLinkEpoch(_ link: BLEIngressLinkID) {
+        lastAttemptAt.removeValue(forKey: link)
+    }
+
+    mutating func removeAll() {
+        lastAttemptAt.removeAll()
+    }
+}

bitchat/Services/BLE/BLEService.swift

@@ -241,6 +241,7 @@ final class BLEService: NSObject {
     // that the session was established *on this current ingress link*, not
     // merely that some session exists for the claimed ID. bleQueue-owned.
     private var noiseAuthenticatedLinkOwners: [BLEIngressLinkID: PeerID] = [:]
+    private var noiseReconnectPolicy = BLENoiseReconnectPolicy()
 
     // Rotation-rebind cooldown per link UUID (bleQueue-owned, like the link
     // store): entries older than the cooldown are pruned on insert.
@@ -311,6 +312,9 @@ final class BLEService: NSObject {
     /// May block in tests to hold the serial message queue immediately before
     /// the deferred private-media admission check.
     var _test_beforePrivateMediaDeferredSend: ((String) -> Void)?
+    /// May block announce handling after verified-link rebind work is queued.
+    /// Tests use this boundary to prove rebind and reconnect are serialized.
+    var _test_afterVerifiedDirectRebindEnqueued: (() -> Void)?
     #endif
     private var selfBroadcastTracker = BLESelfBroadcastTracker()
     private let meshTopology = MeshTopologyTracker()
@@ -764,6 +768,8 @@ final class BLEService: NSObject {
 
         bleQueue.sync {
             pendingWriteBuffers.removeAll()
+            noiseAuthenticatedLinkOwners.removeAll()
+            noiseReconnectPolicy.removeAll()
             connectionScheduler.reset()
         }
         disconnectNotifyDebouncer.removeAll()
@@ -1061,6 +1067,7 @@ final class BLEService: NSObject {
         bleQueue.sync {
             linkStateStore.clearAll()
             noiseAuthenticatedLinkOwners.removeAll()
+            noiseReconnectPolicy.removeAll()
             connectionScheduler.reset()
             subscriptionAnnounceLimiter.removeAll()
         }
@@ -2617,6 +2624,7 @@ final class BLEService: NSObject {
             }
             for link in departedLinks {
                 noiseAuthenticatedLinkOwners.removeValue(forKey: link)
+                noiseReconnectPolicy.endLinkEpoch(link)
             }
         }
         _ = collectionsQueue.sync(flags: .barrier) {
@@ -2929,14 +2937,21 @@ extension BLEService: CBCentralManagerDelegate {
             startScanning()
 
         case .poweredOff:
-            // Bluetooth was turned off - stop scanning and clean up connection state
+            // CoreBluetooth has already transitioned out of poweredOn. Do
+            // not issue stop/cancel commands now; they are rejected as API
+            // misuse. Retire our link state locally instead.
             SecureLogger.info("📴 Bluetooth powered off - cleaning up central state", category: .session)
-            central.stopScan()
-            // Mark all peripheral connections as disconnected (they are now invalid)
             let peripheralStates = linkStateStore.peripheralStates
             let peerIDs: [PeerID] = peripheralStates.compactMap(\.peerID)
             for state in peripheralStates {
-                central.cancelPeripheralConnection(state.peripheral)
+                let peripheralID = state.peripheral.identifier.uuidString
+                collectionsQueue.sync(flags: .barrier) {
+                    pendingPeripheralWrites.discardAll(for: peripheralID)
+                }
+                noiseAuthenticatedLinkOwners.removeValue(
+                    forKey: .peripheral(peripheralID)
+                )
+                noiseReconnectPolicy.endLinkEpoch(.peripheral(peripheralID))
             }
             _ = linkStateStore.clearPeripherals()
             // Notify UI of disconnections
@@ -2949,7 +2964,6 @@ extension BLEService: CBCentralManagerDelegate {
         case .unauthorized:
             // User denied Bluetooth permission
             SecureLogger.warning("🚫 Bluetooth unauthorized - user denied permission", category: .session)
-            central.stopScan()
             _ = linkStateStore.clearPeripherals()
 
         case .unsupported:
@@ -3097,6 +3111,7 @@ extension BLEService: CBCentralManagerDelegate {
             pendingPeripheralWrites.discardAll(for: peripheralID)
         }
         noiseAuthenticatedLinkOwners.removeValue(forKey: .peripheral(peripheralID))
+        noiseReconnectPolicy.endLinkEpoch(.peripheral(peripheralID))
         _ = linkStateStore.removePeripheral(peripheralID)
         // A duplicate link can drop while the peer stays live on another
         // (the dual-role central link, or a second bound link after a
@@ -3151,6 +3166,7 @@ extension BLEService: CBCentralManagerDelegate {
             pendingPeripheralWrites.discardAll(for: peripheralID)
         }
         noiseAuthenticatedLinkOwners.removeValue(forKey: .peripheral(peripheralID))
+        noiseReconnectPolicy.endLinkEpoch(.peripheral(peripheralID))
         _ = linkStateStore.removePeripheral(peripheralID)
         
         SecureLogger.error("❌ Failed to connect to peripheral: \(peripheral.name ?? "Unknown") [\(peripheralID)] - Error: \(error?.localizedDescription ?? "Unknown")", category: .session)
@@ -3258,6 +3274,7 @@ extension BLEService {
                 self.pendingPeripheralWrites.discardAll(for: peripheralID)
             }
             self.noiseAuthenticatedLinkOwners.removeValue(forKey: .peripheral(peripheralID))
+            self.noiseReconnectPolicy.endLinkEpoch(.peripheral(peripheralID))
             _ = self.linkStateStore.removePeripheral(peripheralID)
             self.connectionScheduler.recordConnectionTimeout(peripheralID: peripheralID, at: Date())
             self.tryConnectFromQueue()
@@ -3838,8 +3855,19 @@ extension BLEService: CBPeripheralManagerDelegate {
         case .poweredOff:
             // Bluetooth was turned off - clean up peripheral state
             SecureLogger.info("📴 Bluetooth powered off - cleaning up peripheral state", category: .session)
-            peripheral.stopAdvertising()
             // Clear subscribed centrals (they are now invalid)
+            let centralSnapshot = linkStateStore.subscribedCentralSnapshot
+            for central in centralSnapshot.centrals {
+                let centralID = central.identifier.uuidString
+                noiseAuthenticatedLinkOwners.removeValue(
+                    forKey: .central(centralID)
+                )
+                noiseReconnectPolicy.endLinkEpoch(.central(centralID))
+            }
+            collectionsQueue.sync(flags: .barrier) {
+                pendingNotifications.removeAll()
+                pendingWriteBuffers.removeAll()
+            }
             let centralPeerIDs = linkStateStore.clearCentrals()
             subscriptionAnnounceLimiter.removeAll()
             characteristic = nil
@@ -3853,7 +3881,6 @@ extension BLEService: CBPeripheralManagerDelegate {
         case .unauthorized:
             // User denied Bluetooth permission
             SecureLogger.warning("🚫 Bluetooth unauthorized for peripheral role", category: .session)
-            peripheral.stopAdvertising()
             _ = linkStateStore.clearCentrals()
             subscriptionAnnounceLimiter.removeAll()
             characteristic = nil
@@ -3966,6 +3993,7 @@ extension BLEService: CBPeripheralManagerDelegate {
             pendingNotifications.removeTarget { $0.identifier.uuidString == centralID }
         }
         noiseAuthenticatedLinkOwners.removeValue(forKey: .central(centralID))
+        noiseReconnectPolicy.endLinkEpoch(.central(centralID))
         let removedPeerID = linkStateStore.removeSubscribedCentral(central)
         
         // Ensure we're still advertising for other devices to find us
@@ -4583,6 +4611,40 @@ extension BLEService {
             })
         }
     }
+
+    /// A peer-level session can outlive the physical link that established it.
+    /// Revalidate a fresh direct link with an ordinary XX exchange, retiring
+    /// cached sending keys atomically before message 1 can leave.
+    private func refreshNoiseSessionForVerifiedDirectLink(
+        _ packet: BitchatPacket,
+        peerID: PeerID
+    ) {
+        guard let link = collectionsQueue.sync(execute: { ingressLinks.link(for: packet) }) else {
+            return
+        }
+
+        let hasEstablishedSession = noiseService.hasEstablishedSession(with: peerID)
+        let authenticatedPeerLinks = currentNoiseAuthenticatedLinks(to: peerID)
+        let shouldRevalidate = readLinkState { store in
+            guard boundPeerID(for: link, in: store) == peerID else {
+                return false
+            }
+            return noiseReconnectPolicy.shouldRevalidate(
+                on: link,
+                hasEstablishedSession: hasEstablishedSession,
+                isNoiseAuthenticatedLink: noiseAuthenticatedLinkOwners[link] == peerID,
+                hasAuthenticatedPeerLink: !authenticatedPeerLinks.isEmpty,
+                now: Date()
+            )
+        }
+        guard shouldRevalidate else { return }
+
+        SecureLogger.info(
+            "🔄 Revalidating cached Noise session on fresh direct link to \(peerID.id.prefix(8))…",
+            category: .session
+        )
+        initiateNoiseReconnectHandshake(with: peerID)
+    }
     
     private func configureNoiseServiceCallbacks(for service: NoiseEncryptionService) {
         service.onPeerAuthenticatedWithGeneration = { [weak self] peerID, fingerprint, generation in
@@ -4595,13 +4657,94 @@ extension BLEService {
                 )
             }
         }
-        service.onRekeyHandshakeReady = { [weak self] peerID, message in
-            self?.messageQueue.async { [weak self] in
-                guard let self else { return }
+        service.onRekeyHandshakeReady = {
+            [weak self, weak service] peerID, initiation in
+            self?.messageQueue.async(flags: .barrier) {
+                [weak self, weak service] in
+                guard let self,
+                      let service,
+                      self.noiseService === service else {
+                    return
+                }
                 self.noteNoiseSessionCleared(for: peerID)
+                guard let message = service.claimHandshakeInitiation(
+                    initiation,
+                    for: peerID
+                ) else {
+                    return
+                }
                 self.broadcastNoiseHandshake(message, to: peerID)
             }
         }
+        service.onHandshakeRecoveryRequired = {
+            [weak self, weak service] request in
+            guard let self, let service else { return }
+            self.messageQueue.async(flags: .barrier) {
+                [weak self, weak service] in
+                guard let self,
+                      let service,
+                      self.noiseService === service else {
+                    return
+                }
+                let peerID = request.peerID
+                guard self.isPeerReachable(peerID) else {
+                    service.cancelHandshakeRecovery(request)
+                    return
+                }
+
+                do {
+                    guard let preparation =
+                        try service.prepareHandshakeRecovery(request) else {
+                        return
+                    }
+                    switch preparation {
+                    case .ordinary(let initiation):
+                        self.noteNoiseSessionCleared(for: peerID)
+                        guard let handshakeData =
+                            service.claimHandshakeInitiation(
+                                initiation,
+                                for: peerID
+                            ) else {
+                            return
+                        }
+                        self.broadcastNoiseHandshake(
+                            handshakeData,
+                            to: peerID
+                        )
+                    case .transferred:
+                        return
+                    }
+                } catch {
+                    SecureLogger.error(
+                        "Failed to prepare handshake recovery with \(peerID.id.prefix(8))…: \(error)",
+                        category: .session
+                    )
+                }
+            }
+        }
+        service.onSessionRestoredWithGeneration = { [weak self, weak service] peerID, generation in
+            guard let self, let service else { return }
+            self.messageQueue.async { [weak self, weak service] in
+                guard let self,
+                      let service,
+                      self.noiseService === service,
+                      let fingerprint = service.getPeerFingerprint(peerID) else {
+                    return
+                }
+                SecureLogger.debug(
+                    "🔐 Restored quarantined Noise session with \(peerID.id.prefix(8))…",
+                    category: .session
+                )
+                // Re-enter the same generation-bound transition used after a
+                // successful handshake. This restores authenticated protocol
+                // state and drains both PM and typed-payload queues.
+                self.handleNoisePeerAuthenticated(
+                    peerID: peerID,
+                    fingerprint: fingerprint,
+                    sessionGeneration: generation
+                )
+            }
+        }
     }
 
     private func handleNoisePeerAuthenticated(
@@ -4855,8 +4998,9 @@ extension BLEService {
             }
             return
         }
-        guard noiseService.hasSession(with: peerID) else {
-            // No session yet - queue the payload SYNCHRONOUSLY before initiating handshake
+        guard noiseService.hasEstablishedSession(with: peerID) else {
+            // No established session yet - queue the payload synchronously
+            // before initiating a handshake
             // to prevent race where fast handshake completion drains empty queue
             collectionsQueue.sync(flags: .barrier) {
                 self.pendingNoiseSessionQueues.appendTypedPayload(typedPayload, for: peerID)
@@ -5786,6 +5930,7 @@ extension BLEService {
                     self.pendingPeripheralWrites.discardAll(for: peripheralID)
                 }
                 self.noiseAuthenticatedLinkOwners.removeValue(forKey: .peripheral(peripheralID))
+                self.noiseReconnectPolicy.endLinkEpoch(.peripheral(peripheralID))
                 _ = self.linkStateStore.removePeripheral(peripheralID)
                 cancelled += 1
             }
@@ -5851,12 +5996,27 @@ extension BLEService {
     }
     
     private func initiateNoiseHandshake(with peerID: PeerID) {
-        // Use NoiseEncryptionService for handshake
-        guard !noiseService.hasSession(with: peerID) else { return }
-        
+        let service = noiseService
         do {
-            let handshakeData = try noiseService.initiateHandshake(with: peerID)
-            broadcastNoiseHandshake(handshakeData, to: peerID)
+            guard let initiation = try service.initiateHandshakeIfNeeded(
+                with: peerID,
+                retryOnTimeout: true
+            ) else {
+                return
+            }
+            messageQueue.async(flags: .barrier) {
+                [weak self, weak service] in
+                guard let self,
+                      let service,
+                      self.noiseService === service,
+                      let handshakeData = service.claimHandshakeInitiation(
+                        initiation,
+                        for: peerID
+                      ) else {
+                    return
+                }
+                self.broadcastNoiseHandshake(handshakeData, to: peerID)
+            }
         } catch {
             SecureLogger.error("Failed to initiate handshake: \(error)")
         }
@@ -5874,6 +6034,42 @@ extension BLEService {
         )
         broadcastPacket(packet)
     }
+
+    /// Starts a wire-compatible ordinary XX reconnect. The manager prepares
+    /// the initiator before atomically retiring the cached transport; the
+    /// one-shot claim prevents a crossed inbound message from making a stale
+    /// message 1 leave after this peer has already become responder.
+    private func initiateNoiseReconnectHandshake(with peerID: PeerID) {
+        let service = noiseService
+        do {
+            let initiation = try service.initiateReconnectHandshake(
+                with: peerID,
+                retryOnTimeout: true
+            )
+            messageQueue.async(flags: .barrier) { [weak self, weak service] in
+                guard let self,
+                      let service,
+                      self.noiseService === service else {
+                    return
+                }
+                self.noteNoiseSessionCleared(for: peerID)
+                guard let handshakeData = service.claimHandshakeInitiation(
+                          initiation,
+                          for: peerID
+                      ) else {
+                    return
+                }
+                self.broadcastNoiseHandshake(handshakeData, to: peerID)
+            }
+        } catch NoiseSessionError.notEstablished {
+            initiateNoiseHandshake(with: peerID)
+        } catch {
+            SecureLogger.error(
+                "Failed to initiate ordinary reconnect: \(error)",
+                category: .session
+            )
+        }
+    }
     
     private func sendPendingMessagesAfterHandshake(for peerID: PeerID) {
         // Atomically take all pending messages to process (prevents concurrent modification)
@@ -6429,6 +6625,9 @@ extension BLEService {
         // consolidate duplicate same-role connections onto that link.
         if let result, result.isVerified, result.isDirectAnnounce {
             rebindLinkAfterVerifiedDirectAnnounce(packet, to: result.peerID)
+            #if DEBUG
+            _test_afterVerifiedDirectRebindEnqueued?()
+            #endif
             retireRedundantPeripheralLinks(packet, to: result.peerID)
         }
 
@@ -6462,11 +6661,9 @@ extension BLEService {
             deliverCourierMailRemotely(to: result.peerID, noiseKey: noiseKey)
             if result.isDirectAnnounce,
                !hasCurrentNoiseAuthenticatedLink(to: result.peerID) {
-                if noiseService.hasEstablishedSession(with: result.peerID) {
-                    // A session with no surviving authenticated link is stale;
-                    // force the current link to prove possession again.
-                    clearNoiseSession(for: result.peerID)
-                }
+                // A cached session may predate this physical link.
+                // rebindLinkAfterVerifiedDirectAnnounce performs its atomic
+                // ordinary reconnect after the binding is published.
                 if !noiseService.hasSession(with: result.peerID) {
                     initiateNoiseHandshake(with: result.peerID)
                 }
@@ -6495,7 +6692,14 @@ extension BLEService {
                 linkUUID = centralUUID
                 previousPeerID = self.linkStateStore.peerID(forCentralUUID: centralUUID)
             }
-            guard let previousPeerID, previousPeerID != peerID else { return }
+            guard let previousPeerID else { return }
+            guard previousPeerID != peerID else {
+                self.refreshNoiseSessionForVerifiedDirectLink(
+                    packet,
+                    peerID: peerID
+                )
+                return
+            }
 
             // The signature does not authenticate directness (TTL is excluded
             // from signing because relays mutate it), so a "verified direct"
@@ -6522,12 +6726,20 @@ extension BLEService {
             // it across an announce-driven rebind, whose direct TTL is
             // replayable; the new owner must complete a fresh handshake.
             self.noiseAuthenticatedLinkOwners.removeValue(forKey: link)
+            self.noiseReconnectPolicy.endLinkEpoch(link)
             switch link {
             case .peripheral(let peripheralUUID):
                 self.linkStateStore.bindPeripheral(peripheralUUID, to: peerID)
             case .central(let centralUUID):
                 self.linkStateStore.bindCentral(centralUUID, to: peerID)
             }
+            // Keep the rebind and reconnect decision in one bleQueue critical
+            // section. No observer may see the new binding while a cached
+            // peer-level sender is still considered established.
+            self.refreshNoiseSessionForVerifiedDirectLink(
+                packet,
+                peerID: peerID
+            )
             SecureLogger.debug("🔄 Rebinding link after peer-ID rotation: \(previousPeerID.id.prefix(8))… → \(peerID.id.prefix(8))…", category: .session)
             self.refreshLocalTopology()
             // The announce that triggered this rebind was upserted as
@@ -6619,6 +6831,7 @@ extension BLEService {
                 pendingPeripheralWrites.discardAll(for: uuid)
             }
             noiseAuthenticatedLinkOwners.removeValue(forKey: .peripheral(uuid))
+            noiseReconnectPolicy.endLinkEpoch(.peripheral(uuid))
             _ = linkStateStore.removePeripheral(uuid)
             SecureLogger.info(
                 "🔗 Retiring redundant link \(uuid.prefix(8))… bound to \(peerID.id.prefix(8))…\(keptUUID.map { " (keeping \($0.prefix(8))…)" } ?? "")",
@@ -7004,9 +7217,14 @@ extension BLEService {
         let wasEstablished = noiseService.hasEstablishedSession(with: peerID)
         let processed = noisePacketHandler.handleHandshake(packet, from: peerID)
         let isEstablished = noiseService.hasEstablishedSession(with: peerID)
+        if wasEstablished,
+           packet.payload.count == NoiseSecurityConstants.xxInitialMessageSize,
+           !isEstablished {
+            noteNoiseSessionCleared(for: peerID)
+        }
         // XX message 1 is exactly the unauthenticated 32-byte ephemeral key.
-        // While replacing an existing session, do not authenticate its ingress
-        // link until a later message completes and validates the candidate.
+        // During an ordinary reconnect, do not authenticate its ingress link
+        // until a later message completes and proves the responder identity.
         let completedAuthenticatedHandshake = !wasEstablished
             || packet.payload.count != NoiseSecurityConstants.xxInitialMessageSize
         if processed, isEstablished, completedAuthenticatedHandshake {

bitchat/Services/NoiseEncryptionService.swift

@@ -184,11 +184,17 @@ final class NoiseEncryptionService {
     private var onPeerAuthenticatedHandlers: [((PeerID, String) -> Void)] = [] // Array of handlers for peer authentication
     private var onPeerAuthenticatedWithGenerationHandlers: [((PeerID, String, UUID) -> Void)] = []
     var onHandshakeRequired: ((PeerID) -> Void)? // peerID needs handshake
-    /// Automatic rekey removed the old session and produced XX message 1.
-    /// The transport must clear session-scoped state and put these exact bytes
-    /// on the wire; merely reporting "handshake required" strands the partial
-    /// initiator session because a second initiate call sees it already exists.
-    var onRekeyHandshakeReady: ((_ peerID: PeerID, _ message: Data) -> Void)?
+    /// Automatic rekey prepared XX message 1. The transport must claim the
+    /// exact attempt at its actual BLE handoff; a crossed inbound initiation
+    /// can invalidate the token before that point.
+    var onRekeyHandshakeReady:
+        ((_ peerID: PeerID, _ initiation: NoiseHandshakeInitiation) -> Void)?
+    var onHandshakeRecoveryRequired:
+        ((_ request: NoiseHandshakeRecoveryRequest) -> Void)?
+    /// An unauthenticated reconnect attempt failed or timed out and the
+    /// receive-only rollback session became the active transport again.
+    /// Transport queues must be drained for this exact restored generation.
+    var onSessionRestoredWithGeneration: ((_ peerID: PeerID, _ generation: UUID) -> Void)?
     
     // Add a handler for peer authentication
     func addOnPeerAuthenticatedHandler(_ handler: @escaping (PeerID, String) -> Void) {
@@ -219,7 +225,17 @@ final class NoiseEncryptionService {
         }
     }
     
-    init(keychain: KeychainManagerProtocol) {
+    init(
+        keychain: KeychainManagerProtocol,
+        ordinaryHandshakeTimeout: TimeInterval =
+            NoiseSecurityConstants.ordinaryHandshakeTimeout,
+        ordinaryResponderHandshakeTimeout: TimeInterval =
+            NoiseSecurityConstants.ordinaryResponderHandshakeTimeout,
+        recentInitiatorCompletionGracePeriod: TimeInterval =
+            NoiseSecurityConstants.recentInitiatorCompletionGracePeriod,
+        ordinaryReconnectRollbackCooldown: TimeInterval =
+            NoiseSecurityConstants.ordinaryReconnectRollbackCooldown
+    ) {
         self.keychain = keychain
         self.localPrekeys = LocalPrekeyStore(keychain: keychain)
 
@@ -309,7 +325,17 @@ final class NoiseEncryptionService {
         self.signingPublicKey = signingKey.publicKey
 
         // Initialize session manager
-        self.sessionManager = NoiseSessionManager(localStaticKey: staticIdentityKey, keychain: keychain)
+        self.sessionManager = NoiseSessionManager(
+            localStaticKey: staticIdentityKey,
+            keychain: keychain,
+            ordinaryHandshakeTimeout: ordinaryHandshakeTimeout,
+            ordinaryResponderHandshakeTimeout:
+                ordinaryResponderHandshakeTimeout,
+            recentInitiatorCompletionGracePeriod:
+                recentInitiatorCompletionGracePeriod,
+            ordinaryReconnectRollbackCooldown:
+                ordinaryReconnectRollbackCooldown
+        )
 
         // Set up session callbacks
         sessionManager.onSessionEstablished = { [weak self] peerID, remoteStaticKey, generation in
@@ -319,6 +345,12 @@ final class NoiseEncryptionService {
                 sessionGeneration: generation
             )
         }
+        sessionManager.onSessionRestored = { [weak self] peerID, generation in
+            self?.onSessionRestoredWithGeneration?(peerID, generation)
+        }
+        sessionManager.onHandshakeRecoveryRequired = { [weak self] request in
+            self?.onHandshakeRecoveryRequired?(request)
+        }
 
         // Start session maintenance timer
         startRekeyTimer()
@@ -682,6 +714,90 @@ final class NoiseEncryptionService {
         let handshakeData = try sessionManager.initiateHandshake(with: peerID)
         return handshakeData
     }
+
+    /// Atomically admits and prepares one initial ordinary handshake. Returns
+    /// nil when another discovery callback already created a session.
+    func initiateHandshakeIfNeeded(
+        with peerID: PeerID,
+        retryOnTimeout: Bool = false
+    ) throws -> NoiseHandshakeInitiation? {
+        guard peerID.isValid else {
+            SecureLogger.warning(.authenticationFailed(peerID: peerID.id))
+            throw NoiseSecurityError.invalidPeerID
+        }
+
+        guard let initiation = try sessionManager.initiateHandshakeIfAbsent(
+            with: peerID,
+            notifyOnTimeout: retryOnTimeout,
+            authorize: { [rateLimiter] in
+                guard rateLimiter.allowHandshake(from: peerID) else {
+                    SecureLogger.warning(
+                        .authenticationFailed(peerID: "Rate limited: \(peerID)")
+                    )
+                    throw NoiseSecurityError.rateLimitExceeded
+                }
+            }
+        ) else {
+            return nil
+        }
+        SecureLogger.info(.handshakeStarted(peerID: peerID.id))
+        return initiation
+    }
+
+    /// Atomically prepares an ordinary reconnect for a peer whose cached
+    /// transport belongs to an earlier physical link. Failed authorization or
+    /// handshake setup preserves the established session.
+    func initiateReconnectHandshake(
+        with peerID: PeerID,
+        retryOnTimeout: Bool = false
+    ) throws -> NoiseHandshakeInitiation {
+        guard peerID.isValid else {
+            SecureLogger.warning(.authenticationFailed(peerID: peerID.id))
+            throw NoiseSecurityError.invalidPeerID
+        }
+
+        return try sessionManager.initiateReconnectHandshake(
+            with: peerID,
+            notifyOnTimeout: retryOnTimeout,
+            authorize: { [rateLimiter] in
+                guard rateLimiter.allowHandshake(from: peerID) else {
+                    SecureLogger.warning(
+                        .authenticationFailed(peerID: "Rate limited: \(peerID)")
+                    )
+                    throw NoiseSecurityError.rateLimitExceeded
+                }
+            }
+        )
+    }
+
+    func prepareHandshakeRecovery(
+        _ request: NoiseHandshakeRecoveryRequest
+    ) throws -> NoiseHandshakeRecoveryPreparation? {
+        try sessionManager.prepareHandshakeRecovery(
+            request,
+            authorizeAttempt: { [rateLimiter] in
+                guard rateLimiter.allowHandshake(from: request.peerID) else {
+                    SecureLogger.warning(
+                        .authenticationFailed(
+                            peerID: "Rate limited: \(request.peerID)"
+                        )
+                    )
+                    throw NoiseSecurityError.rateLimitExceeded
+                }
+            }
+        )
+    }
+
+    func cancelHandshakeRecovery(_ request: NoiseHandshakeRecoveryRequest) {
+        sessionManager.cancelHandshakeRecovery(request)
+    }
+
+    func claimHandshakeInitiation(
+        _ initiation: NoiseHandshakeInitiation,
+        for peerID: PeerID
+    ) -> Data? {
+        sessionManager.claimHandshakeInitiation(initiation, for: peerID)
+    }
     
     /// Process an incoming handshake message
     func processHandshakeMessage(from peerID: PeerID, message: Data) throws -> Data? {
@@ -706,7 +822,10 @@ final class NoiseEncryptionService {
         
         // For handshakes, we process the raw data directly without NoiseMessage wrapper
         // The Noise protocol handles its own message format
-        let responsePayload = try sessionManager.handleIncomingHandshake(from: peerID, message: message)
+        let responsePayload = try sessionManager.handleIncomingHandshake(
+            from: peerID,
+            message: message
+        )
         
         
         // Return raw response without wrapper
@@ -804,8 +923,10 @@ final class NoiseEncryptionService {
             throw NoiseSecurityError.rateLimitExceeded
         }
         
-        // Check if we have an established session
-        guard hasEstablishedSession(with: peerID) else {
+        // A quarantined transport is deliberately unavailable for outbound
+        // state, but remains receive-only until the responder proves identity
+        // or the bounded rollback restores it.
+        guard sessionManager.hasReceiveSession(for: peerID) else {
             throw NoiseEncryptionError.sessionNotEstablished
         }
         
@@ -928,9 +1049,9 @@ final class NoiseEncryptionService {
     }
 
     private func initiateAutomaticRekey(for peerID: PeerID) throws {
-        let handshakeMessage = try sessionManager.initiateRekey(for: peerID)
+        let initiation = try sessionManager.initiateRekey(for: peerID)
         SecureLogger.debug("Key rotation initiated for peer: \(peerID)", category: .security)
-        onRekeyHandshakeReady?(peerID, handshakeMessage)
+        onRekeyHandshakeReady?(peerID, initiation)
         onHandshakeRequired?(peerID)
     }
 

bitchatTests/BLEServiceCoreTests.swift

@@ -502,14 +502,26 @@ struct BLEServiceCoreTests {
         )
         let replay = try #require(victim.signPacket(unsigned), "Failed to sign replayed announce")
         #expect(ble._test_recordIngressIfNew(packet: replay, linkID: attackerLink))
+        let rebindGate = VerifiedDirectRebindGate()
+        ble._test_afterVerifiedDirectRebindEnqueued = rebindGate.pause
+        defer {
+            rebindGate.release()
+            ble._test_afterVerifiedDirectRebindEnqueued = nil
+        }
         ble._test_handlePacket(replay, fromPeerID: victimPeerID, preseedPeer: false)
 
-        let rebound = await TestHelpers.waitUntil(
-            { ble._test_centralBinding(attackerLink) == victimPeerID },
+        let announcePaused = await TestHelpers.waitUntil(
+            { rebindGate.hasPaused },
             timeout: TestConstants.longTimeout
         )
-        #expect(rebound)
-        #expect(ble.canDeliverSecurely(to: victimPeerID))
+        try #require(announcePaused)
+
+        // Rebind and ordinary reconnect preparation are one bleQueue
+        // critical section. Once the binding is visible, stale sending keys
+        // must already be unavailable.
+        #expect(ble._test_centralBinding(attackerLink) == victimPeerID)
+        #expect(!ble.canDeliverSecurely(to: victimPeerID))
+        rebindGate.release()
 
         let outbound = OutboundPacketTap()
         ble._test_onOutboundPacket = { outbound.record($0) }
@@ -529,6 +541,130 @@ struct BLEServiceCoreTests {
         #expect(outbound.count(ofType: .courierEnvelope) == 0)
     }
 
+    @Test
+    func failedInboundReconnectRestoresAndDrainsTypedPayloadQueue() async throws {
+        let ble = makeService()
+        let alice = NoiseEncryptionService(keychain: MockKeychain())
+        let mallory = NoiseEncryptionService(keychain: MockKeychain())
+        let alicePeerID = PeerID(publicKey: alice.getStaticPublicKeyData())
+
+        // Establish BLE as responder so the following inbound reconnect is
+        // not intentionally coalesced by the initiator-completion grace path.
+        let message1 = try alice.initiateHandshake(with: ble.myPeerID)
+        let message2 = try #require(
+            try ble._test_noiseProcessHandshakeMessage(
+                from: alicePeerID,
+                message: message1
+            )
+        )
+        let message3 = try #require(
+            try alice.processHandshakeMessage(
+                from: ble.myPeerID,
+                message: message2
+            )
+        )
+        _ = try ble._test_noiseProcessHandshakeMessage(
+            from: alicePeerID,
+            message: message3
+        )
+        await ble._test_drainNoiseMessagePipeline()
+        #expect(ble.canDeliverSecurely(to: alicePeerID))
+
+        let outbound = OutboundPacketTap()
+        ble._test_onOutboundPacket = outbound.record
+        let forgedMessage1 = try mallory.initiateHandshake(with: ble.myPeerID)
+        let firstPacket = BitchatPacket(
+            type: MessageType.noiseHandshake.rawValue,
+            senderID: Data(hexString: alicePeerID.id) ?? Data(),
+            recipientID: Data(hexString: ble.myPeerID.id),
+            timestamp: UInt64(Date().timeIntervalSince1970 * 1_000),
+            payload: forgedMessage1,
+            signature: nil,
+            ttl: 7
+        )
+        ble._test_handlePacket(firstPacket, fromPeerID: alicePeerID)
+
+        let responseReady = await TestHelpers.waitUntil(
+            {
+                outbound.snapshot().contains {
+                    $0.type == MessageType.noiseHandshake.rawValue
+                        && PeerID(hexData: $0.senderID) == ble.myPeerID
+                        && $0.payload.count
+                            != NoiseSecurityConstants.xxInitialMessageSize
+                }
+            },
+            timeout: TestConstants.longTimeout
+        )
+        try #require(responseReady)
+        let forgedMessage2 = try #require(
+            outbound.snapshot().first {
+                $0.type == MessageType.noiseHandshake.rawValue
+                    && PeerID(hexData: $0.senderID) == ble.myPeerID
+                    && $0.payload.count
+                        != NoiseSecurityConstants.xxInitialMessageSize
+            }?.payload
+        )
+        #expect(!ble.canDeliverSecurely(to: alicePeerID))
+
+        // Typed control traffic must queue behind the ordinary responder,
+        // rather than attempting encryption and disappearing.
+        let privateMessageID = "quarantine-pm-\(UUID().uuidString)"
+        ble.sendPrivateMessage(
+            "queued private message",
+            to: alicePeerID,
+            recipientNickname: "Alice",
+            messageID: privateMessageID
+        )
+        ble.sendGroupInvite(Data("queued-during-quarantine".utf8), to: alicePeerID)
+        await ble._test_drainNoiseMessagePipeline()
+        #expect(outbound.count(ofType: .noiseEncrypted) == 0)
+
+        let forgedMessage3 = try #require(
+            try mallory.processHandshakeMessage(
+                from: ble.myPeerID,
+                message: forgedMessage2
+            )
+        )
+        let thirdPacket = BitchatPacket(
+            type: MessageType.noiseHandshake.rawValue,
+            senderID: Data(hexString: alicePeerID.id) ?? Data(),
+            recipientID: Data(hexString: ble.myPeerID.id),
+            timestamp: UInt64(Date().timeIntervalSince1970 * 1_000) + 1,
+            payload: forgedMessage3,
+            signature: nil,
+            ttl: 7
+        )
+        ble._test_handlePacket(thirdPacket, fromPeerID: alicePeerID)
+
+        // Restore re-enters the generation-bound authentication transition:
+        // authenticated state and both outbound queues drain exactly once.
+        let drained = await TestHelpers.waitUntil(
+            { outbound.count(ofType: .noiseEncrypted) >= 3 },
+            timeout: TestConstants.longTimeout
+        )
+        try #require(drained)
+        await ble._test_drainNoiseMessagePipeline()
+        let plaintexts = try outbound.snapshot()
+            .filter { $0.type == MessageType.noiseEncrypted.rawValue }
+            .map { try alice.decrypt($0.payload, from: ble.myPeerID) }
+        #expect(plaintexts.count == 3)
+        #expect(
+            plaintexts.filter {
+                $0.first == NoisePayloadType.authenticatedPeerState.rawValue
+            }.count == 1
+        )
+        #expect(
+            plaintexts.filter {
+                $0.first == NoisePayloadType.privateMessage.rawValue
+            }.count == 1
+        )
+        #expect(
+            plaintexts.filter {
+                $0.first == NoisePayloadType.groupInvite.rawValue
+            }.count == 1
+        )
+    }
+
     /// A legitimate rotation announce necessarily arrives on a link still
     /// bound to the OLD ID, so its registry upsert stores the new peer
     /// disconnected. The successful rebind must promote it: a healed
@@ -854,6 +990,40 @@ private final class OutboundPacketTap {
         lock.lock(); defer { lock.unlock() }
         return packets.filter { $0.type == type.rawValue }.count
     }
+
+    func snapshot() -> [BitchatPacket] {
+        lock.lock(); defer { lock.unlock() }
+        return packets
+    }
+}
+
+private final class VerifiedDirectRebindGate: @unchecked Sendable {
+    private let condition = NSCondition()
+    private var paused = false
+    private var released = false
+
+    var hasPaused: Bool {
+        condition.lock()
+        defer { condition.unlock() }
+        return paused
+    }
+
+    func pause() {
+        condition.lock()
+        paused = true
+        condition.broadcast()
+        while !released {
+            condition.wait()
+        }
+        condition.unlock()
+    }
+
+    func release() {
+        condition.lock()
+        released = true
+        condition.broadcast()
+        condition.unlock()
+    }
 }
 
 private final class ReceivePacketHandoffGate: @unchecked Sendable {

bitchatTests/Integration/IntegrationTests.swift

@@ -12,6 +12,7 @@ import Testing
 @testable import BitFoundation // to avoid unnecessary public's
 @testable import bitchat
 
+@Suite("Integration Tests", .serialized)
 struct IntegrationTests {
     
     private var helper = TestNetworkHelper()
@@ -272,8 +273,18 @@ struct IntegrationTests {
         // Re-establish Noise handshake explicitly via managers
         do {
             let m1 = try helper.noiseManagers["Bob"]!.initiateHandshake(with: helper.nodes["Alice"]!.peerID)
-            let m2 = try helper.noiseManagers["Alice"]!.handleIncomingHandshake(from: helper.nodes["Bob"]!.peerID, message: m1)!
-            let m3 = try helper.noiseManagers["Bob"]!.handleIncomingHandshake(from: helper.nodes["Alice"]!.peerID, message: m2)!
+            let m2 = try #require(
+                try helper.noiseManagers["Alice"]!.handleIncomingHandshake(
+                    from: helper.nodes["Bob"]!.peerID,
+                    message: m1
+                )
+            )
+            let m3 = try #require(
+                try helper.noiseManagers["Bob"]!.handleIncomingHandshake(
+                    from: helper.nodes["Alice"]!.peerID,
+                    message: m2
+                )
+            )
             _ = try helper.noiseManagers["Alice"]!.handleIncomingHandshake(from: helper.nodes["Bob"]!.peerID, message: m3)
         } catch {
             Issue.record("Failed to re-establish Noise session after restart: \(error)")

bitchatTests/Integration/TestNetworkHelper.swift

@@ -8,6 +8,7 @@
 
 import Foundation
 import CryptoKit
+import Testing
 @testable import BitFoundation // to avoid unnecessary public's
 @testable import bitchat
 
@@ -27,9 +28,14 @@ final class TestNetworkHelper {
         node.mockNickname = name
         nodes[name] = node
         
-        // Create/replace Noise manager for this node
+        // This synchronous helper directly drives all three XX messages and
+        // has no transport callback loop for delayed collision recovery.
         let key = Curve25519.KeyAgreement.PrivateKey()
-        noiseManagers[name] = NoiseSessionManager(localStaticKey: key, keychain: mockKeychain)
+        noiseManagers[name] = NoiseSessionManager(
+            localStaticKey: key,
+            keychain: mockKeychain,
+            recentInitiatorCompletionGracePeriod: 0
+        )
         return node
     }
     
@@ -108,8 +114,18 @@ final class TestNetworkHelper {
               let peer2ID = nodes[node2]?.peerID else { return }
         
         let msg1 = try manager1.initiateHandshake(with: peer2ID)
-        let msg2 = try manager2.handleIncomingHandshake(from: peer1ID, message: msg1)!
-        let msg3 = try manager1.handleIncomingHandshake(from: peer2ID, message: msg2)!
+        let msg2 = try #require(
+            try manager2.handleIncomingHandshake(
+                from: peer1ID,
+                message: msg1
+            )
+        )
+        let msg3 = try #require(
+            try manager1.handleIncomingHandshake(
+                from: peer2ID,
+                message: msg2
+            )
+        )
         _ = try manager2.handleIncomingHandshake(from: peer1ID, message: msg3)
     }
 }

bitchatTests/Noise/NoiseCoverageTests.swift

@@ -5,7 +5,7 @@ import BitFoundation
 
 @testable import bitchat
 
-@Suite("Noise Coverage Tests")
+@Suite("Noise Coverage Tests", .serialized)
 struct NoiseCoverageTests {
     private let keychain = MockKeychain()
     private let aliceStaticKey = Curve25519.KeyAgreement.PrivateKey()
@@ -633,8 +633,16 @@ struct NoiseCoverageTests {
         )
         let replacementSession = try #require(manager.getSession(for: alicePeerID))
 
-        #expect(replacementResponse != nil)
-        #expect(replacementSession !== restartedSession)
+        let localPeerID = PeerID(
+            publicKey: aliceStaticKey.publicKey.rawRepresentation
+        )
+        if localPeerID < alicePeerID {
+            #expect(replacementResponse == nil)
+            #expect(replacementSession === restartedSession)
+        } else {
+            #expect(replacementResponse != nil)
+            #expect(replacementSession !== restartedSession)
+        }
 
         let aliceManager = NoiseSessionManager(localStaticKey: aliceStaticKey, keychain: keychain)
         let bobManager = NoiseSessionManager(localStaticKey: bobStaticKey, keychain: keychain)
@@ -654,7 +662,13 @@ struct NoiseCoverageTests {
             try aliceManager.initiateHandshake(with: alicePeerID)
         }
 
-        let rekeyHandshake = try aliceManager.initiateRekey(for: alicePeerID)
+        let rekeyInitiation = try aliceManager.initiateRekey(for: alicePeerID)
+        let rekeyHandshake = try #require(
+            aliceManager.claimHandshakeInitiation(
+                rekeyInitiation,
+                for: alicePeerID
+            )
+        )
         #expect(!rekeyHandshake.isEmpty)
         let rekeyedSession = try #require(aliceManager.getSession(for: alicePeerID))
 
@@ -667,6 +681,7 @@ struct NoiseCoverageTests {
         let aliceManager = NoiseSessionManager(
             localStaticKey: aliceStaticKey,
             keychain: keychain,
+            recentInitiatorCompletionGracePeriod: 0,
             sessionFactory: { peerID, role in
                 BlockingDecryptNoiseSession(
                     peerID: peerID,

bitchatTests/Noise/NoiseProtocolTests.swift

@@ -357,8 +357,18 @@ struct NoiseProtocolTests {
     
     @Test func peerRestartDetection() throws {
         // Establish initial sessions
-        let aliceManager = NoiseSessionManager(localStaticKey: aliceKey, keychain: mockKeychain)
-        let bobManager = NoiseSessionManager(localStaticKey: bobKey, keychain: mockKeychain)
+        // This test explicitly drives the three synchronous XX messages and
+        // does not exercise the transport's delayed collision recovery.
+        let aliceManager = NoiseSessionManager(
+            localStaticKey: aliceKey,
+            keychain: mockKeychain,
+            recentInitiatorCompletionGracePeriod: 0
+        )
+        let bobManager = NoiseSessionManager(
+            localStaticKey: bobKey,
+            keychain: mockKeychain,
+            recentInitiatorCompletionGracePeriod: 0
+        )
         
         try establishManagerSessions(aliceManager: aliceManager, bobManager: bobManager)
         
@@ -377,15 +387,24 @@ struct NoiseProtocolTests {
         let newHandshake1 = try bobManagerRestarted.initiateHandshake(with: bobPeerID)
         
         // Alice should accept the new handshake (clearing old session)
-        let newHandshake2 = try aliceManager.handleIncomingHandshake(
-            from: alicePeerID, message: newHandshake1)
-        #expect(newHandshake2 != nil)
+        let newHandshake2 = try #require(
+            try aliceManager.handleIncomingHandshake(
+                from: alicePeerID,
+                message: newHandshake1
+            )
+        )
         
         // Complete the new handshake
-        let newHandshake3 = try bobManagerRestarted.handleIncomingHandshake(
-            from: bobPeerID, message: newHandshake2!)
-        #expect(newHandshake3 != nil)
-        _ = try aliceManager.handleIncomingHandshake(from: alicePeerID, message: newHandshake3!)
+        let newHandshake3 = try #require(
+            try bobManagerRestarted.handleIncomingHandshake(
+                from: bobPeerID,
+                message: newHandshake2
+            )
+        )
+        _ = try aliceManager.handleIncomingHandshake(
+            from: alicePeerID,
+            message: newHandshake3
+        )
         
         // Should be able to exchange messages with new sessions
         let testMessage = Data("After restart".utf8)
@@ -543,8 +562,18 @@ struct NoiseProtocolTests {
     
     @Test func nonceDesynchronizationCausesRehandshake() throws {
         // Test that nonce desynchronization leads to proper re-handshake
-        let aliceManager = NoiseSessionManager(localStaticKey: aliceKey, keychain: mockKeychain)
-        let bobManager = NoiseSessionManager(localStaticKey: bobKey, keychain: mockKeychain)
+        // This test explicitly drives the three synchronous XX messages and
+        // does not exercise the transport's delayed collision recovery.
+        let aliceManager = NoiseSessionManager(
+            localStaticKey: aliceKey,
+            keychain: mockKeychain,
+            recentInitiatorCompletionGracePeriod: 0
+        )
+        let bobManager = NoiseSessionManager(
+            localStaticKey: bobKey,
+            keychain: mockKeychain,
+            recentInitiatorCompletionGracePeriod: 0
+        )
         
         // Establish sessions
         try establishManagerSessions(aliceManager: aliceManager, bobManager: bobManager)
@@ -572,15 +601,25 @@ struct NoiseProtocolTests {
         let rehandshake1 = try bobManager.initiateHandshake(with: bobPeerID)
         
         // Alice should accept despite having a "valid" (but desynced) session
-        let rehandshake2 = try aliceManager.handleIncomingHandshake(
-            from: alicePeerID, message: rehandshake1)
-        #expect(rehandshake2 != nil, "Alice should accept handshake to fix desync")
+        let rehandshake2 = try #require(
+            try aliceManager.handleIncomingHandshake(
+                from: alicePeerID,
+                message: rehandshake1
+            ),
+            "Alice should accept handshake to fix desync"
+        )
         
         // Complete handshake
-        let rehandshake3 = try bobManager.handleIncomingHandshake(
-            from: bobPeerID, message: rehandshake2!)
-        #expect(rehandshake3 != nil)
-        _ = try aliceManager.handleIncomingHandshake(from: alicePeerID, message: rehandshake3!)
+        let rehandshake3 = try #require(
+            try bobManager.handleIncomingHandshake(
+                from: bobPeerID,
+                message: rehandshake2
+            )
+        )
+        _ = try aliceManager.handleIncomingHandshake(
+            from: alicePeerID,
+            message: rehandshake3
+        )
         
         // Verify communication works again
         let testResynced = Data("Resynced".utf8)

bitchatTests/Services/BLENoisePacketHandlerTests.swift

@@ -175,6 +175,24 @@ struct BLENoisePacketHandlerTests {
         #expect(recorder.broadcastPackets.isEmpty)
     }
 
+    @Test
+    func managedHandshakeFailureDoesNotStartASecondRecovery() {
+        let recorder = Recorder()
+        recorder.handshakeResult = .failure(
+            NoiseManagedHandshakeFailure(underlying: TestError())
+        )
+        recorder.hasSession = false
+        let handler = makeHandler(recorder: recorder)
+        let packet = makeHandshakePacket(
+            recipientID: Data(hexString: localPeerID.id)
+        )
+
+        #expect(!handler.handleHandshake(packet, from: remotePeerID))
+        #expect(recorder.hasSessionQueries.isEmpty)
+        #expect(recorder.initiatedHandshakes.isEmpty)
+        #expect(recorder.broadcastPackets.isEmpty)
+    }
+
     // MARK: Encrypted
 
     @Test

bitchatTests/Services/BLENoiseReconnectPolicyTests.swift

@@ -0,0 +1,115 @@
+import BitFoundation
+import Foundation
+import Testing
+@testable import bitchat
+
+@Suite("BLE Noise reconnect policy")
+struct BLENoiseReconnectPolicyTests {
+    @Test("Revalidation requires a cached session and no authenticated link")
+    func revalidationPreconditions() {
+        var policy = BLENoiseReconnectPolicy()
+        let link = BLEIngressLinkID.peripheral("peripheral-a")
+        let now = Date(timeIntervalSince1970: 1_000)
+
+        let withoutSession = policy.shouldRevalidate(
+            on: link,
+            hasEstablishedSession: false,
+            isNoiseAuthenticatedLink: false,
+            hasAuthenticatedPeerLink: false,
+            now: now
+        )
+        #expect(!withoutSession)
+        let authenticated = policy.shouldRevalidate(
+            on: link,
+            hasEstablishedSession: true,
+            isNoiseAuthenticatedLink: true,
+            hasAuthenticatedPeerLink: true,
+            now: now
+        )
+        #expect(!authenticated)
+        let eligible = policy.shouldRevalidate(
+            on: link,
+            hasEstablishedSession: true,
+            isNoiseAuthenticatedLink: false,
+            hasAuthenticatedPeerLink: false,
+            now: now
+        )
+        #expect(eligible)
+    }
+
+    @Test("Revalidation is once per link epoch or after sixty seconds")
+    func revalidationIsBoundPerLinkEpoch() {
+        var policy = BLENoiseReconnectPolicy()
+        let link = BLEIngressLinkID.central("central-a")
+        let start = Date(timeIntervalSince1970: 2_000)
+
+        let initial = policy.shouldRevalidate(
+            on: link,
+            hasEstablishedSession: true,
+            isNoiseAuthenticatedLink: false,
+            hasAuthenticatedPeerLink: false,
+            now: start
+        )
+        #expect(initial)
+        let duringCooldown = policy.shouldRevalidate(
+            on: link,
+            hasEstablishedSession: true,
+            isNoiseAuthenticatedLink: false,
+            hasAuthenticatedPeerLink: false,
+            now: start.addingTimeInterval(59.999)
+        )
+        #expect(!duringCooldown)
+        let afterCooldown = policy.shouldRevalidate(
+            on: link,
+            hasEstablishedSession: true,
+            isNoiseAuthenticatedLink: false,
+            hasAuthenticatedPeerLink: false,
+            now: start.addingTimeInterval(60)
+        )
+        #expect(afterCooldown)
+
+        policy.endLinkEpoch(link)
+        let nextEpoch = policy.shouldRevalidate(
+            on: link,
+            hasEstablishedSession: true,
+            isNoiseAuthenticatedLink: false,
+            hasAuthenticatedPeerLink: false,
+            now: start.addingTimeInterval(60.001)
+        )
+        #expect(nextEpoch)
+    }
+
+    @Test("An authenticated sibling suppresses redundant reconnect")
+    func authenticatedSiblingSuppressesReconnect() {
+        var policy = BLENoiseReconnectPolicy()
+        let link = BLEIngressLinkID.peripheral("unproven-sibling")
+        let start = Date(timeIntervalSince1970: 3_000)
+
+        let suppressed = policy.shouldRevalidate(
+            on: link,
+            hasEstablishedSession: true,
+            isNoiseAuthenticatedLink: false,
+            hasAuthenticatedPeerLink: true,
+            now: start
+        )
+        #expect(!suppressed)
+        let eligible = policy.shouldRevalidate(
+            on: link,
+            hasEstablishedSession: true,
+            isNoiseAuthenticatedLink: false,
+            hasAuthenticatedPeerLink: false,
+            now: start
+        )
+        #expect(eligible)
+    }
+
+    @Test("Reserved replacement bit is not advertised")
+    func reservedReplacementBitIsNotAdvertised() {
+        #expect(
+            !PeerCapabilities.localSupported.contains(
+                .nonDestructiveNoiseReplacement
+            )
+        )
+        #expect(PeerCapabilities.localSupported.contains(.privateMedia))
+    }
+}

localPackages/BitFoundation/Sources/BitFoundation/PeerCapabilities.swift

@@ -28,6 +28,11 @@ public struct PeerCapabilities: OptionSet, Equatable, Hashable, Sendable {
     /// before outer BLE fragmentation. Peers that omit this bit require the
     /// signed directed raw-file migration fallback.
     public static let privateMedia = PeerCapabilities(rawValue: 1 << 8)
+    /// Reserved for test builds that briefly advertised non-destructive Noise
+    /// replacement. Current clients intentionally do not advertise or act on
+    /// this bit; keep it decodable so the wire assignment is never reused.
+    public static let nonDestructiveNoiseReplacement =
+        PeerCapabilities(rawValue: 1 << 10)
 
     /// Minimal little-endian byte encoding; always at least one byte so an
     /// empty set is distinguishable from an absent TLV.

localPackages/BitFoundation/Tests/BitFoundationTests/PeerCapabilitiesTests.swift

@@ -20,6 +20,10 @@ struct PeerCapabilitiesTests {
 
         let high = PeerCapabilities(rawValue: 1 << 9)
         #expect(high.encoded() == Data([0x00, 0x02]))
+        #expect(
+            PeerCapabilities.nonDestructiveNoiseReplacement.encoded()
+                == Data([0x00, 0x04])
+        )
 
         let all: PeerCapabilities = [.prekeys, .wifiBulk, .gateway, .groups, .board, .vouch, .meshDiagnostics, .privateMedia]
         #expect(PeerCapabilities(encoded: all.encoded()) == all)