如何强制刷新WCF服务的安全令牌？

Question

我有一个WCF服务,需要由单独的WCF STS服务发出的安全令牌.这一切都只是花花公子.在我的应用程序中,我使用这样的服务:

MyServiceClient myService = new MyServiceClient();
myService.Open();
myService.DoStuff();

调用STS服务获取令牌,令牌用于调用服务方法DoStuff.

但是,一旦初始握手结束,myService对象就会缓存令牌并重新使用它直到它到期为止.这是很好的行为,但是如何强制它刷新令牌呢？

myService.ClientCredentials.Invalidate(); // something like this?

这样,如果我再次调用DoStuff(),它就会知道它需要再次像第一次那样再次进入STS.

我只是制作一个新的代理类对象,即myService = new MyServiceClient();？这有效,但它似乎是核弹解决方案.

或者,有没有办法只手动获取一个新令牌并替换当前的令牌,即myService.ClientCredentials.Renew();？

如果我必须创建一个自定义ClientCredentials类来执行此操作,我将如何实现上面的示例方法？

Answer 1

在我的代码库中，我们实际上缓存了令牌，因此我们确保不会重复调用 STS。使用相同的方法，您绝对可以随时更改它，手动请求另一个令牌。以下是连接 ClientCredentials 的方法：

public class CustomClientCredentials : ClientCredentials
{
    public CustomClientCredentials()
    {
    }

    protected CustomClientCredentials(ClientCredentials other)
        : base(other)
    {
    }

    protected override ClientCredentials CloneCore()
    {
        return new CustomClientCredentials(this);
    }

    /// <summary>
    /// Returns a custom security token manager
    /// </summary>
    /// <returns></returns>
    public override  SecurityTokenManager CreateSecurityTokenManager()
    {
        return new CustomClientCredentialsSecurityTokenManager(this);
    }
}


public class CustomClientCredentialsSecurityTokenManager : ClientCredentialsSecurityTokenManager
{
    public CustomClientCredentialsSecurityTokenManager(ClientCredentials credentials)
        : base(credentials)
    {
    }

    /// <summary>
    /// Returns a custom token provider when a issued token is required
    /// </summary>
    public override SecurityTokenProvider CreateSecurityTokenProvider(SecurityTokenRequirement tokenRequirement)
    {
        if (IsIssuedSecurityTokenRequirement(tokenRequirement))
        {
            // Adds the endpoint behaviors for calling the issuer
            IssuedSecurityTokenProvider baseProvider = (IssuedSecurityTokenProvider)base.CreateSecurityTokenProvider(tokenRequirement);

            CustomIssuedSecurityTokenProvider provider = new CustomIssuedSecurityTokenProvider(baseProvider);
            return provider;
        }
        return base.CreateSecurityTokenProvider(tokenRequirement);
    }
}


public class CustomIssuedSecurityTokenProvider : IssuedSecurityTokenProvider
{
    private readonly IssuedSecurityTokenProvider _innerProvider;

    public CustomIssuedSecurityTokenProvider(IssuedSecurityTokenProvider innerProvider)
    {
        _innerProvider = innerProvider;
        CacheIssuedTokens = innerProvider.CacheIssuedTokens;
        IdentityVerifier = innerProvider.IdentityVerifier;
        IssuedTokenRenewalThresholdPercentage = innerProvider.IssuedTokenRenewalThresholdPercentage;
        IssuerAddress = innerProvider.IssuerAddress;
        IssuerBinding = innerProvider.IssuerBinding;
        innerProvider.IssuerChannelBehaviors.ForEach(IssuerChannelBehaviors.Add);
        KeyEntropyMode = innerProvider.KeyEntropyMode;
        MaxIssuedTokenCachingTime = innerProvider.MaxIssuedTokenCachingTime;
        MessageSecurityVersion = innerProvider.MessageSecurityVersion;
        SecurityAlgorithmSuite = innerProvider.SecurityAlgorithmSuite;
        SecurityTokenSerializer = innerProvider.SecurityTokenSerializer;
        TargetAddress = innerProvider.TargetAddress;
        innerProvider.TokenRequestParameters.ForEach(TokenRequestParameters.Add);

        _innerProvider.Open();
    }

    ~CustomIssuedSecurityTokenProvider()
    {
        _innerProvider.Close();
    }

    protected override SecurityToken GetTokenCore(TimeSpan timeout)
    {
        // We're ignoring the CacheIssuedTokens property in order to force an STS call
        var securityToken = _innerProvider.GetToken(timeout);
        return securityToken;
    }
}

GetTokenCore() 方法是调用 STS 的地方。当您调用GetToken()时，STS将被要求发行另一个令牌。

根据您的问题，我假设您知道如何从 app.config 挂钩到您的 ClientCredentials。

可能有一种方法可以在 App.config 文件中设置 CacheIssuedTokens 属性，但我只是不确定有什么方法可以解决。