core-data – NSFileProtectionComplete不加密核心数据文件

我正在使用 Xcode 7.3 for iOS 9.3来尝试加密Core Data文件.我正在尝试使用NSPersistentStoreFileProtectionKey并将其设置为NSFileProtectionComplete以启用加密.它由于某种原因无法工作,我总能看到应用程序生成的.sqlite文件,并浏览sqlitebrowser或iexplorer中的内容.这是我的代码：

lazy var persistentStoreCoordinator: NSPersistentStoreCoordinator = {
    // The persistent store coordinator for the application. This implementation creates and returns a coordinator,having added the store for the application to it. This property is optional since there are legitimate error conditions that could cause the creation of the store to fail.

    // Create the coordinator and store
    let coordinator = NSPersistentStoreCoordinator(managedObjectModel: self.managedObjectModel)
    let url = self.applicationDocumentsDirectory.URLByAppendingPathComponent("SingleViewCoreData.sqlite")
    var failureReason = "There was an error creating or loading the application's saved data."


    let dict: [NSObject : AnyObject] = [
        NSPersistentStoreFileProtectionKey        : NSFileProtectionComplete
    ]

    do {
        try coordinator.addPersistentStoreWithType(NSSQLiteStoreType,configuration: nil,URL: url,options: dict)
    } catch {
        // Report any error we got.
        var dict = [String: AnyObject]()
        dict[NSLocalizedDescriptionKey] = "Failed to initialize the application's saved data"
        dict[NSLocalizedFailureReasonErrorKey] = failureReason

        dict[NSUnderlyingErrorKey] = error as NSError
        let wrappedError = NSError(domain: "YOUR_ERROR_DOMAIN",code: 9999,userInfo: dict)
        // Replace this with code to handle the error appropriately.
        // abort() causes the application to generate a crash log and terminate. You should not use this function in a shipping application,although it may be useful during development.
        NSLog("Unresolved error \(wrappedError),\(wrappedError.userInfo)")
        abort()
    }

    do {
        let url = self.applicationDocumentsDirectory.URLByAppendingPathComponent("SingleViewCoreData.sqlite")
        try NSFileManager.defaultManager().setAttributes([NSFileProtectionKey : NSFileProtectionComplete],ofItemAtPath: url.path!)

    } catch {

    }

    do {
        let url = self.applicationDocumentsDirectory.URLByAppendingPathComponent("SingleViewCoreData.sqlite-wal")
        try NSFileManager.defaultManager().setAttributes([NSFileProtectionKey : NSFileProtectionComplete],ofItemAtPath: url.path!)
        //            try print(NSFileManager.defaultManager().attributesOfFileSystemForPath(String(url)))

    } catch {

    }

    do {
        let url = self.applicationDocumentsDirectory.URLByAppendingPathComponent("SingleViewCoreData.sqlite-shm")
        try NSFileManager.defaultManager().setAttributes([NSFileProtectionKey : NSFileProtectionComplete],ofItemAtPath: url.path!)
        //            try print(NSFileManager.defaultManager().attributesOfFileSystemForPath(String(url)))

    } catch {

    }


    return coordinator
}()

我还在“功能”中为我的目标启用了数据保护.我已从Apple Developer门户重新生成配置文件,并将其与Enabled Data Protection一起使用.

我还使用以下代码来检查.sqlite,.sqlite-wal和.sqlite-shm文件的文件属性.正确为所有3个NSFileProtectionKey设置了它.

func checkProtectionForLocalDb(atDir : String){

    let fileManager = NSFileManager.defaultManager()
    let enumerator: NSDirectoryEnumerator = fileManager.enumeratorAtPath(atDir)!


    for path in enumerator {

        let attr : NSDictionary = enumerator.fileAttributes!
        print(attr)


    }


}

我还尝试禁用日记模式以防止创建-wal和-shm文件.但我仍然可以阅读.sqlite文件.即使属性读取NSFileProtectionComplete.

如Apple文档Apple Docs“使用磁盘加密保护数据”中所述,我尝试检查变量protectedDataAvailable的值是否发生了变化,如下面的代码所示

public func applicationDidEnterBackground(application: UIApplication) {
    // Use this method to release shared resources,save user data,invalidate timers,and store enough application state information to restore your application to its current state in case it is terminated later.
    // If your application supports background execution,this method is called instead of applicationWillTerminate: when the user quits.
    NSThread.sleepForTimeInterval(10)
    sleep(10)
    let dataAvailable : Bool = UIApplication.sharedApplication().protectedDataAvailable
    print("Protected Data Available : " + String(dataAvailable))

}

如果我在没有延迟的情况下检查该值,则将其设置为true,但在添加延迟后将其设置为false.然而,这是一种令人鼓舞的事情,当我下载容器以显示内容时,它仍然具有.sqlite文件,在sqlitebrowser中打开时仍显示内容.

好的,我终于理解了这一点.

使用Xcode 7.3.1 ..

启用文件保护

>使用应用目标上的功能选项卡启用文件保护
>如果您不想使用默认的NSFileProtectionComplete,请在应用程序ID下的开发人员门户中更改此设置
>确保XCode具有此创建的新配置文件.
>为了保护您的应用创建的文件,就是这样.
>要保护Core Data,您需要将NSPersistentStoreFileProtectionKey：NSFileProtectionComplete选项添加到持久性存储中.

例：

var options: [NSObject : AnyObject] = [NSMigratePersistentStoresAutomaticallyOption: true,NSPersistentStoreFileProtectionKey: NSFileProtectionComplete,NSInferMappingModelAutomaticallyOption: true]
    do {
        try coordinator!.addPersistentStoreWithType(NSSQLiteStoreType,options: options)

测试文件保护

我无法使用连接到计算机的非越狱设备对此进行测试.每次以这种方式访问​​设备的尝试都要求我“信任”计算机,我相信可信任的计算机始终能够读取手机的数据(“可信计算机可以与您的iOS设备同步,创建备份,以及访问设备的照片,视频,联系人和其他内容“ – https://support.apple.com/en-us/HT202778).我认为SO引用此技术的其他答案对于更新版本的iOS不再有效.实际上,我总是能够使用XCode下载容器并使用iPhone Explorer查看应用程序的数据.那么如何测试……

1 – 通过从命令行在.app文件上运行以下命令,创建存档并确保其具有正确的权利：

codesign -d --entitlements :- <path_to_app_binary>

您应该看到代表您的数据保护级别的键/值对.在这个例子中,NSFileProtectionComplete：

<key>com.apple.developer.default-data-protection</key>
<string>NSFileProtectionComplete</string>

另外,我使用以下两种技术来确保数据保护确实有效.它们都需要更改代码.

2 – 添加一些代码以验证是否在文件和/或核心数据存储上设置了正确的NSFileProtectionKey：

NSFileManager.defaultManager().attributesOfItemAtPath(dbPath.path!)

如果我在我的一个文件上打印出来,我会得到：

["NSFileCreationDate": 2016-10-14 02:06:39 +0000,"NSFileGroupOwnerAccountName": mobile,"NSFileType": NSFileTypeRegular,"NSFileSystemNumber": 16777218,"NSFileOwnerAccountName": mobile,"NSFileReferenceCount": 1,"NSFileModificationDate": 2016-10-14 02:06:39 +0000,"NSFileExtensionHidden": 0,"NSFileSize": 81920,"NSFileGroupOwnerAccountID": 501,"NSFileOwnerAccountID": 501,"NSFilePosixPermissions": 420,"NSFileProtectionKey": NSFileProtectionComplete,"NSFileSystemFileNumber": 270902]

注意“NSFileProtectionKey”：NSFileProtectionComplete对.

3 – 修改以下代码并将其连接到应用程序中的某个按钮.

@IBAction func settingButtonTouch(sender: AnyObject) {
        updateTimer = NSTimer.scheduledTimerWithTimeInterval(0.5,target: self,selector: #selector(TabbedOverviewViewController.runTest),userInfo: nil,repeats: true)
        registerBackgroundTask()
}

var backgroundTask: UIBackgroundTaskIdentifier = UIBackgroundTaskInvalid
var updateTimer: NSTimer?

func registerBackgroundTask() {
    backgroundTask = UIApplication.sharedApplication().beginBackgroundTaskWithExpirationHandler {
        [unowned self] in
        self.endBackgroundTask()
    }
    assert(backgroundTask != UIBackgroundTaskInvalid)
}

func endBackgroundTask() {
    NSLog("Background task ended.")
    UIApplication.sharedApplication().endBackgroundTask(backgroundTask)
    backgroundTask = UIBackgroundTaskInvalid
}

func runTest() {
    switch UIApplication.sharedApplication().applicationState {
    case .Active:
        NSLog("App is active.")
        checkFiles()
    case .Background:
        NSLog("App is backgrounded.")
        checkFiles()
    case .Inactive:
        break
    }
}

func checkFiles() {
    //attempt to access a protected resource,i.e. a core data store or file
}

当您点击按钮时,此代码每隔0.5秒开始执行checkFiles方法.这应该在应用程序的前台或后台无限期运行 – 直到您锁定手机.此时它应该在大约10秒后可靠地失败 – 完全如NSFileProtectionComplete的描述中所述.