ASP.NET 5 授权针对两个或多个策略(或组合策略)

ASP.NET 5 Authorize against two or more policies (OR-combined policy)

是否可以针对两个或多个策略申请授权?我正在使用 ASP.NET 5, rc1.

[Authorize(Policy = "Limited,Full")]
public class FooBarController : Controller
{
    // This code doesn't work
}

如果没有,我如何在不使用政策的情况下实现这一目标?有两组用户可以访问此控制器:"Full" 和 "Limited"。用户可能属于 "Full" 或 "Limited",或两者兼而有之。他们只需要属于两个组之一即可访问此控制器。

不是你想要的方式;政策旨在累积。例如,如果您使用两个单独的属性,那么它们都必须通过。

您必须在单个策略中评估 OR 条件。 但是您不必在单个处理程序中将其编码为 OR。您可以有一个具有多个处理程序的需求。如果任一处理程序标记成功,则满足要求。请参阅我的 Authorization Workshop.

中的第 6 步

设置新政策后"LimitedOrFull"(假设它们与声明类型名称匹配)创建如下要求:

options.AddPolicy("LimitedOrFull", policy =>
    policy.RequireAssertion(context =>
        context.User.HasClaim(c =>
            (c.Type == "Limited" ||
             c.Type == "Full"))));

https://docs.microsoft.com/en-us/aspnet/core/security/authorization/policies?view=aspnetcore-2.1#using-a-func-to-fulfill-a-policy

Net Core 可以选择拥有多个具有相同 AuthorizationRequirement 类型的 AuthorizationHandler。只有其中一个必须成功才能通过授权 https://docs.microsoft.com/en-us/aspnet/core/security/authorization/policies?view=aspnetcore-2.1#why-would-i-want-multiple-handlers-for-a-requirement

我使用策略和角色:

[Authorize(Policy = "ManagerRights", Roles = "Administrator")]

使用动态创建需求的解决方案最适合我:

  1. 创建单独的“有限”和“完整”政策要求的界面:
    public interface ILimitedRequirement : IAuthorizationRequirement { }
    public interface IFullRequirement : IAuthorizationRequirement { }
  1. 为授权创建自定义属性:
    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = true)]
    public class AuthorizeAnyAttribute : AuthorizeAttribute {

        public string[] Policies { get; }

        public AuthorizeAnyAttribute(params string[] policies) : base(String.Join("Or", policies))
            => Policies = policies;
    }
  1. ILimitedRequirementIFullRequirement 创建授权处理程序(请注意,这些处理程序处理 接口 ,而不是 类):
    public class LimitedRequirementHandler : AuthorizationHandler<ILimitedRequirement> {

        protected override async Task HandleRequirementAsync(AuthorizationHandlerContext context, ILimitedRequirement requirement) {
            if(limited){
                context.Succeed(requirement);
            }
        }
    }

    public class FullRequirementHandler : AuthorizationHandler<IFullRequirement> {

        protected override async Task HandleRequirementAsync(AuthorizationHandlerContext context, IFullRequirement requirement) {
            if(full){
                context.Succeed(requirement);
            }
        }
    }
  1. 如果您的授权处理程序很繁重(例如,其中一个访问数据库)并且您不希望其中一个执行授权检查是否另一个已经成功或失败,您可以使用下一个解决方法(记住处理程序注册的顺序直接决定了它们在请求管道中的执行顺序):
    public static class AuthorizationExtensions {

        public static bool IsAlreadyDetermined<TRequirement>(this AuthorizationHandlerContext context)
            where TRequirement : IAuthorizationRequirement
            => context.HasFailed || context.HasSucceeded
                || !context.PendingRequirements.Any(x => x is TRequirement);

    }


    public class LimitedRequirementHandler : AuthorizationHandler<ILimitedRequirement> {

        protected override async Task HandleRequirementAsync(AuthorizationHandlerContext context, ILimitedRequirement requirement) {
            if(context.IsAlreadyDetermined<ILimitedRequirement>())
                return;

            if(limited){
                context.Succeed(requirement);
            }
        }
    }

    public class FullRequirementHandler : AuthorizationHandler<IFullRequirement> {

        protected override async Task HandleRequirementAsync(AuthorizationHandlerContext context, IFullRequirement requirement) {
            if(context.IsAlreadyDetermined<IFullRequirement>())
                return;

            if(full){
                context.Succeed(requirement);
            }
        }
    }
  1. 注册授权处理程序(注意没有“LimiterOrFullRequirementHandler”,这两个处理程序将处理组合策略要求):
    //Order of handlers is important - it determines their execution order in request pipeline
    services.AddScoped<IAuthorizationHandler, LimitedRequirementHandler>();
    services.AddScoped<IAuthorizationHandler, FullRequirementHandler>();
  1. 现在我们需要检索所有 AuthorizeAny 属性并使用 ImpromptuInterface(或任何其他用于动态创建类型实例的工具)为它们动态创建需求:
    using ImpromptuInterface;

    List<AuthorizeAnyAttribute> attributes  = new List<AuthorizeAnyAttribute>();

    foreach(Type type in Assembly.GetExecutingAssembly().GetTypes().Where(type => type.IsAssignableTo(typeof(ControllerBase)))) {
        attributes.AddRange(Attribute.GetCustomAttributes(type , typeof(AuthorizeAnyAttribute))
            .Cast<AuthorizeAnyAttribute>()
            .Where(x => x.Policy != null));
        foreach(var methodInfo in type.GetMethods()) {
            attributes.AddRange(Attribute.GetCustomAttributes(methodInfo , typeof(AuthorizeAnyAttribute))
            .Cast<AuthorizeAnyAttribute>()
            .Where(x => x.Policy != null));
        }
    }
    
    //Add base requirement interface from which all requirements will be created on demand
    Dictionary<string, Type> baseRequirementTypes = new();
    baseRequirementTypes.Add("Limited", typeof(ILimitedRequirement));
    baseRequirementTypes.Add("Full", typeof(IFullRequirement));
    
    Dictionary<string, IAuthorizationRequirement> requirements = new();
    
    foreach(var attribute in attributes) {
        if(!requirements.ContainsKey(attribute.Policy)) {
            Type[] requirementTypes = new Type[attribute.Policies.Length];
            for(int i = 0; i < attribute.Policies.Length; i++) {
                if(!baseRequirementTypes.TryGetValue(attribute.Policies[i], out Type requirementType))
                    throw new ArgumentException($"Requirement for {attribute.Policies[i]} policy doesn't exist");
                requirementTypes[i] = requirementType;
            }
            //Creating instance of combined requirement dynamically
            IAuthorizationRequirement newRequirement = new { }.ActLike(requirementTypes);
            requirements.Add(attribute.Policy, newRequirement);
        }
    }
  1. 注册所有创建的需求
    services.AddAuthorization(options => {
        foreach(KeyValuePair<string, IAuthorizationRequirement> item in requirements) {
             options.AddPolicy(item.Key, x => x.AddRequirements(item.Value));
        }
    }

如果默认 AuthorizeAttribute 与自定义 AuthorizeAnyAttribute

处理相同,则上述解决方案允许处理与 OR 组合相同的单一需求

如果上述解决方案有点矫枉过正,始终可以使用手动组合类型创建和注册:

  1. 创建组合的“有限或完整”策略要求:
    public class LimitedOrFullRequirement : ILimitedRequirement, IFullRequirement { }
  1. 如果这两个要求也必须单独使用(除了使用组合的“有限或完整”策略),请为单个要求创建接口实现:
    public class LimitedRequirement : ILimitedRequirement { }
    public class FullRequirement : IFullRequirement { }
  1. 注册政策(请注意,注释掉的政策 完全可选 注册):
    services.AddAuthorization(options => {
                options.AddPolicy("Limited Or Full",
                    policy => policy.AddRequirements(new LimitedOrFullRequirement()));
                //If these policies also have single use, they need to be registered as well
                //options.AddPolicy("Limited",
                //  policy => policy.AddRequirements(new LimitedRequirement()));
                //options.AddPolicy("Full",
                //  policy => policy.AddRequirements(new FullRequirement()));
            });