尝试查询存储 NSData 的密钥时，Xamarin.iOS 钥匙串挂起

Question

我有一个现有的企业部署应用程序，它使用OpenID Connect 进行身份验证。一旦通过身份验证，我将 AuthState 对象存储在 iOS 钥匙串中以确保安全，并且以后能够仅使用 Face/Touch ID 登录用户（假设 AuthState 中的刷新令牌仍然有效）。 AuthState 对象如下所示：

namespace OpenId.AppAuth
{
    [Register ("OIDAuthState", true)]
    public class AuthState : NSObject, INSCoding, INativeObject, IDisposable, INSSecureCoding
    {
        [CompilerGenerated]
        private static readonly IntPtr class_ptr = Class.GetHandle ("OIDAuthState");

        [CompilerGenerated]
        private object __mt_ErrorDelegate_var;

        [CompilerGenerated]
        private object __mt_StateChangeDelegate_var;

        public override IntPtr ClassHandle {
            get;
        }

        [CompilerGenerated]
        public virtual NSError AuthorizationError {
            [Export ("authorizationError")]
            get;
        }

        [CompilerGenerated]
        public virtual IAuthStateErrorDelegate ErrorDelegate {
            [Export ("errorDelegate", ArgumentSemantic.Weak)]
            get;
            [Export ("setErrorDelegate:", ArgumentSemantic.Weak)]
            set;
        }

        [CompilerGenerated]
        public virtual bool IsAuthorized {
            [Export ("isAuthorized")]
            get;
        }

        [CompilerGenerated]
        public virtual AuthorizationResponse LastAuthorizationResponse {
            [Export ("lastAuthorizationResponse")]
            get;
        }

        [CompilerGenerated]
        public virtual RegistrationResponse LastRegistrationResponse {
            [Export ("lastRegistrationResponse")]
            get;
        }

        [CompilerGenerated]
        public virtual TokenResponse LastTokenResponse {
            [Export ("lastTokenResponse")]
            get;
        }

        [CompilerGenerated]
        public virtual string RefreshToken {
            [Export ("refreshToken")]
            get;
        }

        [CompilerGenerated]
        public virtual string Scope {
            [Export ("scope")]
            get;
        }

        [CompilerGenerated]
        public virtual IAuthStateChangeDelegate StateChangeDelegate {
            [Export ("stateChangeDelegate", ArgumentSemantic.Weak)]
            get;
            [Export ("setStateChangeDelegate:", ArgumentSemantic.Weak)]
            set;
        }

        public static IAuthorizationFlowSession PresentAuthorizationRequest (AuthorizationRequest authorizationRequest, UIViewController presentingViewController, AuthStateAuthorizationCallback callback);

        [CompilerGenerated]
        [DesignatedInitializer]
        [EditorBrowsable (EditorBrowsableState.Advanced)]
        [Export ("initWithCoder:")]
        public AuthState (NSCoder coder)
            : base (NSObjectFlag.Empty);

        [CompilerGenerated]
        [EditorBrowsable (EditorBrowsableState.Advanced)]
        protected AuthState (NSObjectFlag t)
            : base (t);

        [CompilerGenerated]
        [EditorBrowsable (EditorBrowsableState.Advanced)]
        protected internal AuthState (IntPtr handle)
            : base (handle);

        [Export ("initWithAuthorizationResponse:")]
        [CompilerGenerated]
        public AuthState (AuthorizationResponse authorizationResponse)
            : base (NSObjectFlag.Empty);

        [Export ("initWithAuthorizationResponse:tokenResponse:")]
        [CompilerGenerated]
        public AuthState (AuthorizationResponse authorizationResponse, TokenResponse tokenResponse)
            : base (NSObjectFlag.Empty);

        [Export ("initWithRegistrationResponse:")]
        [CompilerGenerated]
        public AuthState (RegistrationResponse registrationResponse)
            : base (NSObjectFlag.Empty);

        [Export ("initWithAuthorizationResponse:tokenResponse:registrationResponse:")]
        [DesignatedInitializer]
        [CompilerGenerated]
        public AuthState (AuthorizationResponse authorizationResponse, TokenResponse tokenResponse, RegistrationResponse registrationResponse)
            : base (NSObjectFlag.Empty);

        [Export ("encodeWithCoder:")]
        [CompilerGenerated]
        [Preserve (Conditional = true)]
        public virtual void EncodeTo (NSCoder encoder);

        [Export ("performActionWithFreshTokens:")]
        [CompilerGenerated]
        public unsafe virtual void PerformWithFreshTokens ([BlockProxy (typeof(ObjCRuntime.Trampolines.NIDAuthStateAction))] AuthStateAction action);

        [Export ("performActionWithFreshTokens:additionalRefreshParameters:")]
        [CompilerGenerated]
        public unsafe virtual void PerformWithFreshTokens ([BlockProxy (typeof(ObjCRuntime.Trampolines.NIDAuthStateAction))] AuthStateAction action, NSDictionary<NSString, NSString> additionalParameters);

        [Export ("authStateByPresentingAuthorizationRequest:UICoordinator:callback:")]
        [CompilerGenerated]
        public unsafe static IAuthorizationFlowSession PresentAuthorizationRequest (AuthorizationRequest authorizationRequest, IAuthorizationUICoordinator UICoordinator, [BlockProxy (typeof(ObjCRuntime.Trampolines.NIDAuthStateAuthorizationCallback))] AuthStateAuthorizationCallback callback);

        [Export ("setNeedsTokenRefresh")]
        [CompilerGenerated]
        public virtual void SetNeedsTokenRefresh ();

        [Export ("tokenRefreshRequest")]
        [CompilerGenerated]
        public virtual TokenRequest TokenRefreshRequest ();

        [Export ("tokenRefreshRequestWithAdditionalParameters:")]
        [CompilerGenerated]
        public virtual TokenRequest TokenRefreshRequest (NSDictionary<NSString, NSString> additionalParameters);

        [Export ("updateWithAuthorizationResponse:error:")]
        [CompilerGenerated]
        public virtual void Update (AuthorizationResponse authorizationResponse, NSError error);

        [Export ("updateWithTokenResponse:error:")]
        [CompilerGenerated]
        public virtual void Update (TokenResponse tokenResponse, NSError error);

        [Export ("updateWithAuthorizationError:")]
        [CompilerGenerated]
        public virtual void Update (NSError authorizationError);

        [Export ("updateWithRegistrationResponse:")]
        [CompilerGenerated]
        public virtual void UpdateWithRegistrationResponse (RegistrationResponse registrationResponse);

        [CompilerGenerated]
        protected override void Dispose (bool disposing);
    }
}

iOS 12.1 更新之前一切正常

问题： 安装 ios 12.1 更新后，仅在以发布模式运行时（在连接到 VS for Mac 调试器时在开发模式下调试时工作）查询存储二进制文件的钥匙串中的现有密钥NSData 表示此 AuthState 对象挂起并最终终止应用程序，因为超过 10 秒无响应。

有没有人遇到过类似的问题？如果有人能阐明这里可能发生的事情或指出我正确的方向，那就太棒了。

附加信息：

我如何获得NSData 对象的AppAuth 二进制表示：

NSData authStateData = NSKeyedArchiver.ArchivedDataWithRootObject(authState);

我如何将这个NSData 保存到钥匙串中：

    var secAccess = new SecAccessControl(SecAccessible.WhenUnlockedThisDeviceOnly, SecAccessControlCreateFlags.UserPresence);
    var secRecord = new SecRecord(SecKind.GenericPassword)
    {
        Account = "keystring",
        Service = "ServiceNameString",
        Label = "keystring",
        ValueData = authStateData,
        AccessControl = secAccess
    };
    var result = SecKeyChain.Add(secRecord);

我如何查询keychain中的现有数据：

var searchRecord = new SecRecord(SecKind.GenericPassword)
{
    Service = ServiceName,
    Label = key,
};
var match = SecKeyChain.QueryAsRecord(searchRecord, out SecStatusCode resultCode);

设备日志中没有明显的错误，我检查了。我错过的 iOS 12.1 中是否有重大影响？

更新：我将代码重构为仅将加密密钥密码存储在钥匙串中而不是整个 AuthState 对象中，并将序列化的 AuthState 加密存储到本地文件中。仍然看到相同的问题，在设备上的调试模式下，一切正常，从钥匙串中写入和读取都很好，当在同一设备上没有附加调试器的情况下运行时，相同的构建，写入正常，在成功验证 TouchID/FaceID 后读取挂起时，是Xamarin.iOS SDK 中是否存在未赶上导致此问题的最新 iOS 中的某些更改的错误？

Answer 1

您应该启用钥匙串共享权利。

在 Entitlements.plist 中

这里有一个similar case，你可以参考。

Answer 2

我已经解决了我遇到的问题，它似乎是某种竞争条件导致应用程序被锁定，因为调用保存到钥匙串是在主线程上完成的。通常，这个调用非常快，过去锁定任何东西都没有问题，但 iOS 12.1 更新中的某些东西改变了这一点。无论如何，我只是在后台线程中显式运行将加密密码保存到钥匙串中的代码，从而解决了问题：

Task.Run(() =>
{
    var keychain = new KeyChain();
    keychain.SetValueForKey("securedvalue", "securedvaluekey");
}).ConfigureAwait(false);