iOS Security Stack 2/5: Concurrency Locks (#33241)

Merged via /review-pr -> /prepare-pr -> /merge-pr.

Prepared head SHA: b99ad804fb
Co-authored-by: mbelinky <132747814+mbelinky@users.noreply.github.com>
Co-authored-by: mbelinky <132747814+mbelinky@users.noreply.github.com>
Reviewed-by: @mbelinky

apps/ios/Sources/Camera/CameraController.swift

@@ -1,6 +1,7 @@
 import AVFoundation
 import OpenClawKit
 import Foundation
+import os
 
 actor CameraController {
     struct CameraDeviceInfo: Codable, Sendable {
@@ -260,7 +261,7 @@ actor CameraController {
 
 private final class PhotoCaptureDelegate: NSObject, AVCapturePhotoCaptureDelegate {
     private let continuation: CheckedContinuation<Data, Error>
-    private var didResume = false
+    private let resumed = OSAllocatedUnfairLock(initialState: false)
 
     init(_ continuation: CheckedContinuation<Data, Error>) {
         self.continuation = continuation
@@ -271,8 +272,12 @@ private final class PhotoCaptureDelegate: NSObject, AVCapturePhotoCaptureDelegat
         didFinishProcessingPhoto photo: AVCapturePhoto,
         error: Error?
     ) {
-        guard !self.didResume else { return }
-        self.didResume = true
+        let alreadyResumed = self.resumed.withLock { old in
+            let was = old
+            old = true
+            return was
+        }
+        guard !alreadyResumed else { return }
 
         if let error {
             self.continuation.resume(throwing: error)
@@ -301,15 +306,19 @@ private final class PhotoCaptureDelegate: NSObject, AVCapturePhotoCaptureDelegat
         error: Error?
     ) {
         guard let error else { return }
-        guard !self.didResume else { return }
-        self.didResume = true
+        let alreadyResumed = self.resumed.withLock { old in
+            let was = old
+            old = true
+            return was
+        }
+        guard !alreadyResumed else { return }
         self.continuation.resume(throwing: error)
     }
 }
 
 private final class MovieFileDelegate: NSObject, AVCaptureFileOutputRecordingDelegate {
     private let continuation: CheckedContinuation<URL, Error>
-    private var didResume = false
+    private let resumed = OSAllocatedUnfairLock(initialState: false)
 
     init(_ continuation: CheckedContinuation<URL, Error>) {
         self.continuation = continuation
@@ -321,8 +330,12 @@ private final class MovieFileDelegate: NSObject, AVCaptureFileOutputRecordingDel
         from connections: [AVCaptureConnection],
         error: Error?)
     {
-        guard !self.didResume else { return }
-        self.didResume = true
+        let alreadyResumed = self.resumed.withLock { old in
+            let was = old
+            old = true
+            return was
+        }
+        guard !alreadyResumed else { return }
 
         if let error {
             let ns = error as NSError

apps/ios/Sources/Gateway/GatewayConnectionController.swift

@@ -9,6 +9,7 @@ import Darwin
 import OpenClawKit
 import Network
 import Observation
+import os
 import Photos
 import ReplayKit
 import Security
@@ -990,12 +991,16 @@ extension GatewayConnectionController {
 #endif
 
 private final class GatewayTLSFingerprintProbe: NSObject, URLSessionDelegate, @unchecked Sendable {
+    private struct ProbeState {
+        var didFinish = false
+        var session: URLSession?
+        var task: URLSessionWebSocketTask?
+    }
+
     private let url: URL
     private let timeoutSeconds: Double
     private let onComplete: (String?) -> Void
-    private var didFinish = false
-    private var session: URLSession?
-    private var task: URLSessionWebSocketTask?
+    private let state = OSAllocatedUnfairLock(initialState: ProbeState())
 
     init(url: URL, timeoutSeconds: Double, onComplete: @escaping (String?) -> Void) {
         self.url = url
@@ -1008,9 +1013,11 @@ private final class GatewayTLSFingerprintProbe: NSObject, URLSessionDelegate, @u
         config.timeoutIntervalForRequest = self.timeoutSeconds
         config.timeoutIntervalForResource = self.timeoutSeconds
         let session = URLSession(configuration: config, delegate: self, delegateQueue: nil)
-        self.session = session
         let task = session.webSocketTask(with: self.url)
-        self.task = task
+        self.state.withLock { s in
+            s.session = session
+            s.task = task
+        }
         task.resume()
 
         DispatchQueue.global(qos: .utility).asyncAfter(deadline: .now() + self.timeoutSeconds) { [weak self] in
@@ -1036,12 +1043,18 @@ private final class GatewayTLSFingerprintProbe: NSObject, URLSessionDelegate, @u
     }
 
     private func finish(_ fingerprint: String?) {
-        objc_sync_enter(self)
-        defer { objc_sync_exit(self) }
-        guard !self.didFinish else { return }
-        self.didFinish = true
-        self.task?.cancel(with: .goingAway, reason: nil)
-        self.session?.invalidateAndCancel()
+        let (shouldComplete, taskToCancel, sessionToInvalidate) = self.state.withLock { s -> (Bool, URLSessionWebSocketTask?, URLSession?) in
+            guard !s.didFinish else { return (false, nil, nil) }
+            s.didFinish = true
+            let task = s.task
+            let session = s.session
+            s.task = nil
+            s.session = nil
+            return (true, task, session)
+        }
+        guard shouldComplete else { return }
+        taskToCancel?.cancel(with: .goingAway, reason: nil)
+        sessionToInvalidate?.invalidateAndCancel()
         self.onComplete(fingerprint)
     }