方法上的多个授权属性

Question

我在为类方法指定两个单独的授权属性时遇到问题：如果两个属性中的任何一个为真，则允许用户访问。

Athorization 类如下所示：

[AttributeUsage(AttributeTargets.All, AllowMultiple = true)]
public class AuthAttribute : AuthorizeAttribute {
. . .

和行动：

[Auth(Roles = AuthRole.SuperAdministrator)]
[Auth(Roles = AuthRole.Administrator, Module = ModuleID.SomeModule)]
public ActionResult Index() {
    return View(GetIndexViewModel());
}

有没有办法解决这个问题，还是我需要重新考虑我的方法？

这将在 MVC2 中运行。

Answer 1

在更高版本的 asp.net 中有一种更好的方法来执行此操作，您可以对角色执行 OR 和 AND。这是通过约定完成的，在单个 Authorize 中列出多个角色将执行 OR，而添加多个 Authorize 属性将执行 AND。

或示例

[Authorize(Roles = "PowerUser,ControlPanelUser")] 

AND 示例

[Authorize(Roles = "PowerUser")]
[Authorize(Roles = "ControlPanelUser")]

您可以在以下链接中找到更多信息 https://docs.microsoft.com/en-us/aspnet/core/security/authorization/roles

Answer 2

多个AuthorizeAttribute 实例由MVC 处理，就像它们与AND 连接一样。如果您想要 OR 行为，您将需要实现自己的检查逻辑。最好实现AuthAttribute 以承担多个角色并使用OR 逻辑执行自己的检查。

另一种解决方案是使用标准 AuthorizeAttribute 并实现自定义 IPrincipal，这将实现 bool IsInRole(string role) 方法以提供“或”行为。

这里有一个例子： https://stackoverflow.com/a/10754108/449906

Answer 3

我在生产环境中使用此解决方案已有一段时间了，使用的是 .NET Core 3.0。我想要 自定义属性 和原生 AuthorizeAttribute 之间的 OR 行为。为此，我实现了IAuthorizationEvaluator 接口，在所有授权者评估其结果后立即调用该接口。

/// <summary>
/// Responsible for evaluating if authorization was successful or not, after execution of
/// authorization handler pipelines.
/// This class was implemented because MVC default behavior is to apply an AND behavior
/// with the result of each authorization handler. But to allow our API to have multiple
/// authorization handlers, in which the final authorization result is if ANY handlers return
/// true, the class <cref name="IAuthorizationEvaluator" /> had to be extended to add this
/// OR behavior.
/// </summary>
public class CustomAuthorizationEvaluator : IAuthorizationEvaluator
{
    /// <summary>
    /// Evaluates the results of all authorization handlers called in the pipeline.
    /// Will fail if: at least ONE authorization handler calls context.Fail() OR none of
    /// authorization handlers call context.Success().
    /// Will succeed if: at least one authorization handler calls context.Success().
    /// </summary>
    /// <param name="context">Shared context among handlers.</param>
    /// <returns>Authorization result.</returns>
    public AuthorizationResult Evaluate(AuthorizationHandlerContext context)
    {
        // If context.Fail() got called in ANY of the authorization handlers:
        if (context.HasFailed == true)
        {
            return AuthorizationResult.Failed(AuthorizationFailure.ExplicitFail());
        }

        // If none handler called context.Fail(), some of them could have called
        // context.Success(). MVC treats the context.HasSucceeded with an AND behavior,
        // meaning that if one of the custom authorization handlers have called 
        // context.Success() and others didn't, the property context.HasSucceeded will be
        // false. Thus, this class is responsible for applying the OR behavior instead of
        // the default AND.

        bool success = 
            context.PendingRequirements.Count() < context.Requirements.Count();

        return success == true 
            ? AuthorizationResult.Success()
            : AuthorizationResult.Failed(AuthorizationFailure.ExplicitFail());
    }
}

只有在添加到 .NET 服务集合（在您的启动类中）时才会调用此评估器，如下所示：

services.AddSingleton<IAuthorizationEvaluator, CustomAuthorizationEvaluator>();

在控制器类中，用两个属性装饰每个方法。在我的情况下，[Authorize] 和 [CustomAuthorize]。

Answer 4

我不确定其他人对此有何看法，但我也想要 OR 行为。在我的AuthorizationHandlers 中，如果其中任何一个通过了，我就打电话给Succeed。请注意，这不适用于没有参数的内置 Authorize 属性。

public class LoggedInHandler : AuthorizationHandler<LoggedInAuthReq>
{
    private readonly IHttpContextAccessor httpContextAccessor;
    public LoggedInHandler(IHttpContextAccessor httpContextAccessor)
    {
        this.httpContextAccessor = httpContextAccessor;
    }

    protected override Task HandleRequirementAsync(AuthorizationHandlerContext context, LoggedInAuthReq requirement)
    {
        var httpContext = httpContextAccessor.HttpContext;
        if (httpContext != null && requirement.IsLoggedIn())
        {
            context.Succeed(requirement);
            foreach (var req in context.Requirements)
            {
                context.Succeed(req);
            }
        }

        return Task.CompletedTask;
    }
}

提供您自己的 LoggedInAuthReq。在启动时将这些注入到服务中

        services.AddAuthorization(o => {
            o.AddPolicy("AadLoggedIn", policy => policy.AddRequirements(new LoggedInAuthReq()));
            ... more here
        });
        services.AddSingleton<IAuthorizationHandler, LoggedInHandler>();
        ... more here

在你的控制器方法中

    [Authorize("FacebookLoggedIn")]
    [Authorize("MsaLoggedIn")]
    [Authorize("AadLoggedIn")]
    [HttpGet("anyuser")]
    public JsonResult AnyUser()
    {
        return new JsonResult(new { I = "did it with Any User!" })
        {
            StatusCode = (int)HttpStatusCode.OK,
        };
    }

这也可以通过单个属性和一堆if 语句来完成。在这种情况下它是works for me。撰写本文时的 asp.net core 2.2。