Custom authorization IActionResults in aspnet-5 mvc-6 - c#

In ASP.NET 4 MVC5, I had this class that allowed me to return custom responses for unauthenticated responses to JSON endpoints. Here it is.
public class CustomAuthorizeAttribute : AuthorizeAttribute
{
protected override void HandleUnauthorizedRequest(AuthorizationContext filterContext)
{
if (IsAjax(filterContext))
{
filterContext.Result = new JsonResult
{
JsonRequestBehavior = JsonRequestBehavior.AllowGet,
Data = new
{
success = false,
error = "You must be signed in."
}
};
}
else
{
base.HandleUnauthorizedRequest(filterContext);
}
}
private bool IsAjax(AuthorizationContext filterContext)
{
return filterContext.ActionDescriptor.GetFilterAttributes(true).OfType<AjaxAttribute>().FirstOrDefault() !=
null;
}
}
However, in MVC6, the new AuthorizeAttribute is no overrides for creating custom IActionResult results. How do I do this in MVC6?

A good point has been made by #blowdart in his comment about whether returning 401/403 should be the expected behaviour. In any case, I have tried a different approach for doing what the OP was asking, modifying the behavior of the default MVC authorization filters so that we return a json when user is unauthorized.
First thing I did was creating a new IAsyncAuthorizationFilter that will format the unauthorized result as a json for ajax request. It will basically:
Wrap an existing filter
Execute the wrapped filter
In case the user is unauthorized by the wrapped filter, return a json for ajax requests
This would be the CustomJsonAuthorizationFilter class:
public class CustomJsonAuthorizationFilter : IAsyncAuthorizationFilter
{
private AuthorizeFilter wrappedFilter;
public CustomJsonAuthorizationFilter(AuthorizeFilter wrappedFilter)
{
this.wrappedFilter = wrappedFilter;
}
public async Task OnAuthorizationAsync(Microsoft.AspNet.Mvc.Filters.AuthorizationContext context)
{
await this.wrappedFilter.OnAuthorizationAsync(context);
if(context.Result != null && IsAjaxRequest(context))
{
context.Result = new JsonResult(new
{
success = false,
error = "You must be signed in."
});
}
return;
}
//This could be an extension method of the HttpContext/HttpRequest
private bool IsAjaxRequest(Microsoft.AspNet.Mvc.Filters.AuthorizationContext filterContext)
{
return filterContext.HttpContext.Request.Headers["X-Requested-With"] == "XMLHttpRequest";
}
}
Then I have created an IApplicationModelProvider in order to wrap all existing AuthorizeFilter with the new custom filter. The AuthroizeFilter is added by AuthorizationApplicationModelProvider, but the new provider will be run after the default one since the order of the default provider is -990.
public class CustomFilterApplicationModelProvider : IApplicationModelProvider
{
public int Order
{
get { return 0; }
}
public void OnProvidersExecuted(ApplicationModelProviderContext context)
{
//Do nothing
}
public void OnProvidersExecuting(ApplicationModelProviderContext context)
{
this.ReplaceFilters(context.Result.Filters);
foreach(var controller in context.Result.Controllers)
{
this.ReplaceFilters(controller.Filters);
foreach (var action in controller.Actions)
{
this.ReplaceFilters(action.Filters);
}
}
}
private void ReplaceFilters(IList<IFilterMetadata> filters)
{
var authorizationFilters = filters.OfType<AuthorizeFilter>().ToList();
foreach (var filter in authorizationFilters)
{
filters.Remove(filter);
filters.Add(new CustomJsonAuthorizationFilter(filter));
}
}
}
Finally, update ConfigureServices in startup with the new application model provider:
services.TryAddEnumerable(
ServiceDescriptor.Transient<IApplicationModelProvider, CustomFilterApplicationModelProvider>());

I finally figured it out after looking at the source.
public class CustomCookieAuthenticationEvents : CookieAuthenticationEvents
{
Func<CookieRedirectContext, Task> _old;
public CustomCookieAuthenticationEvents()
{
_old = OnRedirectToLogin;
OnRedirectToLogin = OnCustomRedirectToLogin;
}
public Task OnCustomRedirectToLogin(CookieRedirectContext context)
{
var actionContext = context.HttpContext.RequestServices.GetRequiredService<IActionContextAccessor>();
if (actionContext.ActionContext == null)
return _old(context);
if (actionContext.ActionContext.ActionDescriptor.FilterDescriptors.Any(x => x.Filter is AjaxAttribute))
{
// this is an ajax request, return custom JSON telling user that they must be authenticated.
var serializerSettings = context
.HttpContext
.RequestServices
.GetRequiredService<IOptions<MvcJsonOptions>>()
.Value
.SerializerSettings;
context.Response.ContentType = "application/json";
using (var writer = new HttpResponseStreamWriter(context.Response.Body, Encoding.UTF8))
{
using (var jsonWriter = new JsonTextWriter(writer))
{
jsonWriter.CloseOutput = false;
var jsonSerializer = JsonSerializer.Create(serializerSettings);
jsonSerializer.Serialize(jsonWriter, new
{
success = false,
error = "You must be signed in."
});
}
}
return Task.FromResult(0);
}
else
{
// this is a normal request to an endpoint that is secured.
// do what ASP.NET used to do.
return _old(context);
}
}
}
Then, use this event class as follows:
services.Configure<IdentityOptions>(options =>
{
options.Cookies.ApplicationCookie.Events = new CustomCookieAuthenticationEvents();
});
ASP.NET 5 sure made simple things harder to do. Granted though, I can now customize things at a more granular level without effecting other pieces. Also, the source code is amazingly easy to read/understand. I am pretty happy having the confidence that any issue I am having can easily be identified as a bug or resolved by looking at the source.
Cheers to the future!

Related

How to move custom authorization attribute policy implementation logic to startup?

I have implemented a custom [Authorize] attribute in a ASP.NET MVC Core 3.1 app. The main reason I have a custom one is because the app uses a lot of AJAX and I couldn't figure out how to get it to work with AJAX. The attribute also implements ActionFilterAttribute instead of IAuthorizationFilter due to issues I posted about here. Having this custom attribute means implementing my own logic to handle roles, which I did.
I've also implemented code to handle policies that group roles, but the code is inside the attribute itself. When a developer would think of changing policies within MVC framework, they'd probably think to go to Startup.cs.
How I could put the logic for policies in Startup.cs and have my custom attribute use it?
Custom attribute:
public class AuthorizeUser : ActionFilterAttribute
{
public Policies Policy { get; set; }
public AuthorizeUser(Policies policy)
{
Policy = policy;
}
public override void OnActionExecuting(ActionExecutingContext context)
{
string signInPageUrl = "/UserAccess/Index";
string notAuthorizedUrl = "/UserAccess/NotAuthorized";
if (context.HttpContext.User.Identity.IsAuthenticated)
{
List<string> roles = GetRolesByPolicy(Policy);
bool userHasRole = false;
foreach (var role in roles)
{
if (context.HttpContext.User.IsInRole(role.ToUpper()))
{
userHasRole = true;
}
}
if (userHasRole == false)
{
if (context.HttpContext.Request.IsAjaxRequest())
{
context.HttpContext.Response.StatusCode = 401;
JsonResult jsonResult = new JsonResult(new { redirectUrl = notAuthorizedUrl });
context.Result = jsonResult;
}
else
{
context.Result = new RedirectResult(notAuthorizedUrl);
}
}
}
else
{
if (context.HttpContext.Request.IsAjaxRequest())
{
context.HttpContext.Response.StatusCode = 403;
JsonResult jsonResult = new JsonResult(new { redirectUrl = signInPageUrl });
context.Result = jsonResult;
}
else
{
context.Result = new RedirectResult(signInPageUrl);
}
}
}
private List<string> GetRolesByPolicy(Policies policy)
{
List<RoleModel.Roles> roleEnums = new List<RoleModel.Roles>();
roleEnums.Add(RoleModel.Roles.Admin); //admin is always allowed all actions
switch (policy)
{
case Policies.EditUsers:
roleEnums.AddRange(new List<RoleModel.Roles>
{
RoleModel.Roles.User,
RoleModel.Roles.Customer,
RoleModel.Roles.Developer,
RoleModel.Roles.Manager
});
break;
case Policies.ManageOrders:
roleEnums.AddRange(new List<RoleModel.Roles>
{
RoleModel.Roles.User,
RoleModel.Roles.Customer
});
break;
case Policies.SendOrders:
roleEnums.AddRange(new List<RoleModel.Roles>
{
RoleModel.Roles.User
});
break;
}
return roleEnums.ConvertAll(r => r.ToString());
}
}
Policies enum
public enum Policies
{
EditUsers,
ManageOrders,
SendOrders
}

Custom authorization attribute implementation [duplicate]

I'm trying to make a custom authorization attribute in ASP.NET Core. In previous versions it was possible to override bool AuthorizeCore(HttpContextBase httpContext). But this no longer exists in AuthorizeAttribute.
What is the current approach to make a custom AuthorizeAttribute?
What I am trying to accomplish: I am receiving a session ID in the Header Authorization. From that ID I'll know whether a particular action is valid.
The approach recommended by the ASP.Net Core team is to use the new policy design which is fully documented here. The basic idea behind the new approach is to use the new [Authorize] attribute to designate a "policy" (e.g. [Authorize( Policy = "YouNeedToBe18ToDoThis")] where the policy is registered in the application's Startup.cs to execute some block of code (i.e. ensure the user has an age claim where the age is 18 or older).
The policy design is a great addition to the framework and the ASP.Net Security Core team should be commended for its introduction. That said, it isn't well-suited for all cases. The shortcoming of this approach is that it fails to provide a convenient solution for the most common need of simply asserting that a given controller or action requires a given claim type. In the case where an application may have hundreds of discrete permissions governing CRUD operations on individual REST resources ("CanCreateOrder", "CanReadOrder", "CanUpdateOrder", "CanDeleteOrder", etc.), the new approach either requires repetitive one-to-one mappings between a policy name and a claim name (e.g. options.AddPolicy("CanUpdateOrder", policy => policy.RequireClaim(MyClaimTypes.Permission, "CanUpdateOrder));), or writing some code to perform these registrations at run time (e.g. read all claim types from a database and perform the aforementioned call in a loop). The problem with this approach for the majority of cases is that it's unnecessary overhead.
While the ASP.Net Core Security team recommends never creating your own solution, in some cases this may be the most prudent option with which to start.
The following is an implementation which uses the IAuthorizationFilter to provide a simple way to express a claim requirement for a given controller or action:
public class ClaimRequirementAttribute : TypeFilterAttribute
{
public ClaimRequirementAttribute(string claimType, string claimValue) : base(typeof(ClaimRequirementFilter))
{
Arguments = new object[] {new Claim(claimType, claimValue) };
}
}
public class ClaimRequirementFilter : IAuthorizationFilter
{
readonly Claim _claim;
public ClaimRequirementFilter(Claim claim)
{
_claim = claim;
}
public void OnAuthorization(AuthorizationFilterContext context)
{
var hasClaim = context.HttpContext.User.Claims.Any(c => c.Type == _claim.Type && c.Value == _claim.Value);
if (!hasClaim)
{
context.Result = new ForbidResult();
}
}
}
[Route("api/resource")]
public class MyController : Controller
{
[ClaimRequirement(MyClaimTypes.Permission, "CanReadResource")]
[HttpGet]
public IActionResult GetResource()
{
return Ok();
}
}
I'm the asp.net security person. Firstly let me apologize that none of this is documented yet outside of the music store sample or unit tests, and it's all still being refined in terms of exposed APIs. Detailed documentation is here.
We don't want you writing custom authorize attributes. If you need to do that we've done something wrong. Instead, you should be writing authorization requirements.
Authorization acts upon Identities. Identities are created by authentication.
You say in comments you want to check a session ID in a header. Your session ID would be the basis for identity. If you wanted to use the Authorize attribute you'd write an authentication middleware to take that header and turn it into an authenticated ClaimsPrincipal. You would then check that inside an authorization requirement. Authorization requirements can be as complicated as you like, for example here's one that takes a date of birth claim on the current identity and will authorize if the user is over 18;
public class Over18Requirement : AuthorizationHandler<Over18Requirement>, IAuthorizationRequirement
{
public override void Handle(AuthorizationHandlerContext context, Over18Requirement requirement)
{
if (!context.User.HasClaim(c => c.Type == ClaimTypes.DateOfBirth))
{
context.Fail();
return;
}
var dobVal = context.User.FindFirst(c => c.Type == ClaimTypes.DateOfBirth).Value;
var dateOfBirth = Convert.ToDateTime(dobVal);
int age = DateTime.Today.Year - dateOfBirth.Year;
if (dateOfBirth > DateTime.Today.AddYears(-age))
{
age--;
}
if (age >= 18)
{
context.Succeed(requirement);
}
else
{
context.Fail();
}
}
}
Then in your ConfigureServices() function you'd wire it up
services.AddAuthorization(options =>
{
options.AddPolicy("Over18",
policy => policy.Requirements.Add(new Authorization.Over18Requirement()));
});
And finally, apply it to a controller or action method with
[Authorize(Policy = "Over18")]
It seems that with ASP.NET Core 2, you can again inherit AuthorizeAttribute, you just need to also implement IAuthorizationFilter (or IAsyncAuthorizationFilter):
[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = true, Inherited = true)]
public class CustomAuthorizeAttribute : AuthorizeAttribute, IAuthorizationFilter
{
private readonly string _someFilterParameter;
public CustomAuthorizeAttribute(string someFilterParameter)
{
_someFilterParameter = someFilterParameter;
}
public void OnAuthorization(AuthorizationFilterContext context)
{
var user = context.HttpContext.User;
if (!user.Identity.IsAuthenticated)
{
// it isn't needed to set unauthorized result
// as the base class already requires the user to be authenticated
// this also makes redirect to a login page work properly
// context.Result = new UnauthorizedResult();
return;
}
// you can also use registered services
var someService = context.HttpContext.RequestServices.GetService<ISomeService>();
var isAuthorized = someService.IsUserAuthorized(user.Identity.Name, _someFilterParameter);
if (!isAuthorized)
{
context.Result = new StatusCodeResult((int)System.Net.HttpStatusCode.Forbidden);
return;
}
}
}
Based on Derek Greer GREAT answer, i did it with enums.
Here is an example of my code:
public enum PermissionItem
{
User,
Product,
Contact,
Review,
Client
}
public enum PermissionAction
{
Read,
Create,
}
public class AuthorizeAttribute : TypeFilterAttribute
{
public AuthorizeAttribute(PermissionItem item, PermissionAction action)
: base(typeof(AuthorizeActionFilter))
{
Arguments = new object[] { item, action };
}
}
public class AuthorizeActionFilter : IAuthorizationFilter
{
private readonly PermissionItem _item;
private readonly PermissionAction _action;
public AuthorizeActionFilter(PermissionItem item, PermissionAction action)
{
_item = item;
_action = action;
}
public void OnAuthorization(AuthorizationFilterContext context)
{
bool isAuthorized = MumboJumboFunction(context.HttpContext.User, _item, _action); // :)
if (!isAuthorized)
{
context.Result = new ForbidResult();
}
}
}
public class UserController : BaseController
{
private readonly DbContext _context;
public UserController( DbContext context) :
base()
{
_logger = logger;
}
[Authorize(PermissionItem.User, PermissionAction.Read)]
public async Task<IActionResult> Index()
{
return View(await _context.User.ToListAsync());
}
}
You can create your own AuthorizationHandler that will find custom attributes on your Controllers and Actions, and pass them to the HandleRequirementAsync method.
public abstract class AttributeAuthorizationHandler<TRequirement, TAttribute> : AuthorizationHandler<TRequirement> where TRequirement : IAuthorizationRequirement where TAttribute : Attribute
{
protected override Task HandleRequirementAsync(AuthorizationHandlerContext context, TRequirement requirement)
{
var attributes = new List<TAttribute>();
var action = (context.Resource as AuthorizationFilterContext)?.ActionDescriptor as ControllerActionDescriptor;
if (action != null)
{
attributes.AddRange(GetAttributes(action.ControllerTypeInfo.UnderlyingSystemType));
attributes.AddRange(GetAttributes(action.MethodInfo));
}
return HandleRequirementAsync(context, requirement, attributes);
}
protected abstract Task HandleRequirementAsync(AuthorizationHandlerContext context, TRequirement requirement, IEnumerable<TAttribute> attributes);
private static IEnumerable<TAttribute> GetAttributes(MemberInfo memberInfo)
{
return memberInfo.GetCustomAttributes(typeof(TAttribute), false).Cast<TAttribute>();
}
}
Then you can use it for any custom attributes you need on your controllers or actions. For example to add permission requirements. Just create your custom attribute.
[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = true)]
public class PermissionAttribute : AuthorizeAttribute
{
public string Name { get; }
public PermissionAttribute(string name) : base("Permission")
{
Name = name;
}
}
Then create a Requirement to add to your Policy
public class PermissionAuthorizationRequirement : IAuthorizationRequirement
{
//Add any custom requirement properties if you have them
}
Then create the AuthorizationHandler for your custom attribute, inheriting the AttributeAuthorizationHandler that we created earlier. It will be passed an IEnumerable for all your custom attributes in the HandleRequirementsAsync method, accumulated from your Controller and Action.
public class PermissionAuthorizationHandler : AttributeAuthorizationHandler<PermissionAuthorizationRequirement, PermissionAttribute>
{
protected override async Task HandleRequirementAsync(AuthorizationHandlerContext context, PermissionAuthorizationRequirement requirement, IEnumerable<PermissionAttribute> attributes)
{
foreach (var permissionAttribute in attributes)
{
if (!await AuthorizeAsync(context.User, permissionAttribute.Name))
{
return;
}
}
context.Succeed(requirement);
}
private Task<bool> AuthorizeAsync(ClaimsPrincipal user, string permission)
{
//Implement your custom user permission logic here
}
}
And finally, in your Startup.cs ConfigureServices method, add your custom AuthorizationHandler to the services, and add your Policy.
services.AddSingleton<IAuthorizationHandler, PermissionAuthorizationHandler>();
services.AddAuthorization(options =>
{
options.AddPolicy("Permission", policyBuilder =>
{
policyBuilder.Requirements.Add(new PermissionAuthorizationRequirement());
});
});
Now you can simply decorate your Controllers and Actions with your custom attribute.
[Permission("AccessCustomers")]
public class CustomersController
{
[Permission("AddCustomer")]
IActionResult AddCustomer([FromBody] Customer customer)
{
//Add customer
}
}
What is the current approach to make a custom AuthorizeAttribute
For pure authorization scenarios (like restricting access to specific users only), the recommended approach is to use the new authorization block: https://github.com/aspnet/MusicStore/blob/1c0aeb08bb1ebd846726232226279bbe001782e1/samples/MusicStore/Startup.cs#L84-L92
public class Startup
{
public void ConfigureServices(IServiceCollection services)
{
services.Configure<AuthorizationOptions>(options =>
{
options.AddPolicy("ManageStore", policy => policy.RequireClaim("Action", "ManageStore"));
});
}
}
public class StoreController : Controller
{
[Authorize(Policy = "ManageStore"), HttpGet]
public async Task<IActionResult> Manage() { ... }
}
For authentication, it's best handled at the middleware level.
What are you trying to achieve exactly?
What?!
I decided to add another simple answer. B/c I find most of these answers a little overengineered. And also because I needed a way to GRANT authorization, not just DENY it. Most of the answers here offer a way to "tighten" security, but I wanted to "loosen" it. For example: "if some application setting is configured, then allow access to anonymous users".
public class MyAuthAttribute : Attribute, IAuthorizationFilter
{
public void OnAuthorization(AuthorizationFilterContext context)
{
//check access
if (CheckPermissions())
{
//all good, add optional code if you want. Or don't
}
else
{
//DENIED!
//return "ChallengeResult" to redirect to login page (for example)
context.Result = new ChallengeResult(CookieAuthenticationDefaults.AuthenticationScheme);
}
}
}
That's it. No need to mess with "policies", "claims", "handlers" and other [beep]
Usage:
// GET api/Get/5
[MyAuth]
public ActionResult<string> Get(int id)
{
return "blahblah";
}
The modern way is AuthenticationHandlers
in startup.cs add
services.AddAuthentication("BasicAuthentication").AddScheme<AuthenticationSchemeOptions, BasicAuthenticationHandler>("BasicAuthentication", null);
public class BasicAuthenticationHandler : AuthenticationHandler<AuthenticationSchemeOptions>
{
private readonly IUserService _userService;
public BasicAuthenticationHandler(
IOptionsMonitor<AuthenticationSchemeOptions> options,
ILoggerFactory logger,
UrlEncoder encoder,
ISystemClock clock,
IUserService userService)
: base(options, logger, encoder, clock)
{
_userService = userService;
}
protected override async Task<AuthenticateResult> HandleAuthenticateAsync()
{
if (!Request.Headers.ContainsKey("Authorization"))
return AuthenticateResult.Fail("Missing Authorization Header");
User user = null;
try
{
var authHeader = AuthenticationHeaderValue.Parse(Request.Headers["Authorization"]);
var credentialBytes = Convert.FromBase64String(authHeader.Parameter);
var credentials = Encoding.UTF8.GetString(credentialBytes).Split(new[] { ':' }, 2);
var username = credentials[0];
var password = credentials[1];
user = await _userService.Authenticate(username, password);
}
catch
{
return AuthenticateResult.Fail("Invalid Authorization Header");
}
if (user == null)
return AuthenticateResult.Fail("Invalid User-name or Password");
var claims = new[] {
new Claim(ClaimTypes.NameIdentifier, user.Id.ToString()),
new Claim(ClaimTypes.Name, user.Username),
};
var identity = new ClaimsIdentity(claims, Scheme.Name);
var principal = new ClaimsPrincipal(identity);
var ticket = new AuthenticationTicket(principal, Scheme.Name);
return AuthenticateResult.Success(ticket);
}
}
IUserService is a service that you make where you have user name and password.
basically it returns a user class that you use to map your claims on.
var claims = new[] {
new Claim(ClaimTypes.NameIdentifier, user.Id.ToString()),
new Claim(ClaimTypes.Name, user.Username),
};
Then you can query these claims and her any data you mapped, ther are quite a few, have a look at ClaimTypes class
you can use this in an extension method an get any of the mappings
public int? GetUserId()
{
if (context.User.Identity.IsAuthenticated)
{
var id=context.User.FindFirst(ClaimTypes.NameIdentifier);
if (!(id is null) && int.TryParse(id.Value, out var userId))
return userId;
}
return new Nullable<int>();
}
This new way, i think is better than the old way as shown here, both work
public class BasicAuthenticationAttribute : AuthorizationFilterAttribute
{
public override void OnAuthorization(HttpActionContext actionContext)
{
if (actionContext.Request.Headers.Authorization != null)
{
var authToken = actionContext.Request.Headers.Authorization.Parameter;
// decoding authToken we get decode value in 'Username:Password' format
var decodeauthToken = System.Text.Encoding.UTF8.GetString(Convert.FromBase64String(authToken));
// spliting decodeauthToken using ':'
var arrUserNameandPassword = decodeauthToken.Split(':');
// at 0th postion of array we get username and at 1st we get password
if (IsAuthorizedUser(arrUserNameandPassword[0], arrUserNameandPassword[1]))
{
// setting current principle
Thread.CurrentPrincipal = new GenericPrincipal(new GenericIdentity(arrUserNameandPassword[0]), null);
}
else
{
actionContext.Response = actionContext.Request.CreateResponse(HttpStatusCode.Unauthorized);
}
}
else
{
actionContext.Response = actionContext.Request.CreateResponse(HttpStatusCode.Unauthorized);
}
}
public static bool IsAuthorizedUser(string Username, string Password)
{
// In this method we can handle our database logic here...
return Username.Equals("test") && Password == "test";
}
}
If anyone just wants to validate a bearer token in the authorize phase using the current security practices you can,
add this to your Startup/ConfigureServices
services.AddSingleton<IAuthorizationHandler, BearerAuthorizationHandler>();
services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme).AddJwtBearer();
services.AddAuthorization(options => options.AddPolicy("Bearer",
policy => policy.AddRequirements(new BearerRequirement())
)
);
and this in your codebase,
public class BearerRequirement : IAuthorizationRequirement
{
public async Task<bool> IsTokenValid(SomeValidationContext context, string token)
{
// here you can check if the token received is valid
return true;
}
}
public class BearerAuthorizationHandler : AuthorizationHandler<BearerRequirement>
{
public BearerAuthorizationHandler(SomeValidationContext thatYouCanInject)
{
...
}
protected override async Task HandleRequirementAsync(AuthorizationHandlerContext context, BearerRequirement requirement)
{
var authFilterCtx = (Microsoft.AspNetCore.Mvc.Filters.AuthorizationFilterContext)context.Resource;
string authHeader = authFilterCtx.HttpContext.Request.Headers["Authorization"];
if (authHeader != null && authHeader.Contains("Bearer"))
{
var token = authHeader.Replace("Bearer ", string.Empty);
if (await requirement.IsTokenValid(thatYouCanInject, token))
{
context.Succeed(requirement);
}
}
}
}
If the code doesn't reach context.Succeed(...) it will Fail anyway (401).
And then in your controllers you can use
[Authorize(Policy = "Bearer", AuthenticationSchemes = JwtBearerDefaults.AuthenticationScheme)]
The below code worked for me in .Net Core 5
[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method)]
public class AccessAuthorizationAttribute : AuthorizeAttribute, IAuthorizationFilter
{
public string Module { get; set; } //Permission string to get from controller
public AccessAuthorizationAttribute(string module)
{
Module = module;
}
public void OnAuthorization(AuthorizationFilterContext context)
{
//Validate if any permissions are passed when using attribute at controller or action level
if (string.IsNullOrEmpty(Module))
{
//Validation cannot take place without any permissions so returning unauthorized
context.Result = new UnauthorizedResult();
return;
}
if (hasAccess)
{
return;
}
context.Result = new UnauthorizedResult();
return;
}
}
The accepted answer (https://stackoverflow.com/a/41348219/4974715) is not realistically maintainable or suitable because "CanReadResource" is being used as a claim (but should essentially be a policy in reality, IMO). The approach at the answer is not OK in the way it was used, because if an action method requires many different claims setups, then with that answer you would have to repeatedly write something like...
[ClaimRequirement(MyClaimTypes.Permission, "CanReadResource")]
[ClaimRequirement(MyClaimTypes.AnotherPermision, "AnotherClaimVaue")]
//and etc. on a single action.
So, imagine how much coding that would take. Ideally, "CanReadResource" is supposed to be a policy that uses many claims to determine if a user can read a resource.
What I do is I create my policies as an enumeration and then loop through and set up the requirements like thus...
services.AddAuthorization(authorizationOptions =>
{
foreach (var policyString in Enum.GetNames(typeof(Enumerations.Security.Policy)))
{
authorizationOptions.AddPolicy(
policyString,
authorizationPolicyBuilder => authorizationPolicyBuilder.Requirements.Add(new DefaultAuthorizationRequirement((Enumerations.Security.Policy)Enum.Parse(typeof(Enumerations.Security.Policy), policyWrtString), DateTime.UtcNow)));
/* Note that thisn does not stop you from
configuring policies directly against a username, claims, roles, etc. You can do the usual.
*/
}
});
The DefaultAuthorizationRequirement class looks like...
public class DefaultAuthorizationRequirement : IAuthorizationRequirement
{
public Enumerations.Security.Policy Policy {get; set;} //This is a mere enumeration whose code is not shown.
public DateTime DateTimeOfSetup {get; set;} //Just in case you have to know when the app started up. And you may want to log out a user if their profile was modified after this date-time, etc.
}
public class DefaultAuthorizationHandler : AuthorizationHandler<DefaultAuthorizationRequirement>
{
private IAServiceToUse _aServiceToUse;
public DefaultAuthorizationHandler(
IAServiceToUse aServiceToUse
)
{
_aServiceToUse = aServiceToUse;
}
protected async override Task HandleRequirementAsync(AuthorizationHandlerContext context, DefaultAuthorizationRequirement requirement)
{
/*Here, you can quickly check a data source or Web API or etc.
to know the latest date-time of the user's profile modification...
*/
if (_aServiceToUse.GetDateTimeOfLatestUserProfileModication > requirement.DateTimeOfSetup)
{
context.Fail(); /*Because any modifications to user information,
e.g. if the user used another browser or if by Admin modification,
the claims of the user in this session cannot be guaranteed to be reliable.
*/
return;
}
bool shouldSucceed = false; //This should first be false, because context.Succeed(...) has to only be called if the requirement specifically succeeds.
bool shouldFail = false; /*This should first be false, because context.Fail()
doesn't have to be called if there's no security breach.
*/
// You can do anything.
await doAnythingAsync();
/*You can get the user's claims...
ALSO, note that if you have a way to priorly map users or users with certain claims
to particular policies, add those policies as claims of the user for the sake of ease.
BUT policies that require dynamic code (e.g. checking for age range) would have to be
coded in the switch-case below to determine stuff.
*/
var claims = context.User.Claims;
// You can, of course, get the policy that was hit...
var policy = requirement.Policy
//You can use a switch case to determine what policy to deal with here...
switch (policy)
{
case Enumerations.Security.Policy.CanReadResource:
/*Do stuff with the claims and change the
value of shouldSucceed and/or shouldFail.
*/
break;
case Enumerations.Security.Policy.AnotherPolicy:
/*Do stuff with the claims and change the
value of shouldSucceed and/or shouldFail.
*/
break;
// Other policies too.
default:
throw new NotImplementedException();
}
/* Note that the following conditions are
so because failure and success in a requirement handler
are not mutually exclusive. They demand certainty.
*/
if (shouldFail)
{
context.Fail(); /*Check the docs on this method to
see its implications.
*/
}
if (shouldSucceed)
{
context.Succeed(requirement);
}
}
}
Note that the code above can also enable pre-mapping of a user to a policy in your data store. So, when composing claims for the user, you basically retrieve the policies that had been pre-mapped to the user directly or indirectly (e.g. because the user has a certain claim value and that claim value had been identified and mapped to a policy, such that it provides automatic mapping for users who have that claim value too), and enlist the policies as claims, such that in the authorization handler, you can simply check if the user's claims contain requirement.Policy as a Value of a Claim item in their claims. That is for a static way of satisfying a policy requirement, e.g. "First name" requirement is quite static in nature. So, for the example above (which I had forgotten to give example on Authorize attribute in my earlier updates to this answer), using the policy with Authorize attribute is like as follows, where ViewRecord is an enum member:
[Authorize(Policy = nameof(Enumerations.Security.Policy.ViewRecord))]
A dynamic requirement can be about checking age range, etc. and policies that use such requirements cannot be pre-mapped to users.
An example of dynamic policy claims checking (e.g. to check if a user is above 18 years old) is already at the answer given by #blowdart (https://stackoverflow.com/a/31465227/4974715).
PS: I typed this on my phone. Pardon any typos and lack of formatting.
As of this writing I believe this can be accomplished with the IClaimsTransformation interface in asp.net core 2 and above. I just implemented a proof of concept which is sharable enough to post here.
public class PrivilegesToClaimsTransformer : IClaimsTransformation
{
private readonly IPrivilegeProvider privilegeProvider;
public const string DidItClaim = "http://foo.bar/privileges/resolved";
public PrivilegesToClaimsTransformer(IPrivilegeProvider privilegeProvider)
{
this.privilegeProvider = privilegeProvider;
}
public async Task<ClaimsPrincipal> TransformAsync(ClaimsPrincipal principal)
{
if (principal.Identity is ClaimsIdentity claimer)
{
if (claimer.HasClaim(DidItClaim, bool.TrueString))
{
return principal;
}
var privileges = await this.privilegeProvider.GetPrivileges( ... );
claimer.AddClaim(new Claim(DidItClaim, bool.TrueString));
foreach (var privilegeAsRole in privileges)
{
claimer.AddClaim(new Claim(ClaimTypes.Role /*"http://schemas.microsoft.com/ws/2008/06/identity/claims/role" */, privilegeAsRole));
}
}
return principal;
}
}
To use this in your Controller just add an appropriate [Authorize(Roles="whatever")] to your methods.
[HttpGet]
[Route("poc")]
[Authorize(Roles = "plugh,blast")]
public JsonResult PocAuthorization()
{
var result = Json(new
{
when = DateTime.UtcNow,
});
result.StatusCode = (int)HttpStatusCode.OK;
return result;
}
In our case every request includes an Authorization header that is a JWT. This is the prototype and I believe we will do something super close to this in our production system next week.
Future voters, consider the date of writing when you vote. As of today, this works on my machine.™ You will probably want more error handling and logging on your implementation.
Just adding to the great answer from #Shawn. If you are using dotnet 5 you need to update the class to be:
public abstract class AttributeAuthorizationHandler<TRequirement, TAttribute> : AuthorizationHandler<TRequirement> where TRequirement : IAuthorizationRequirement where TAttribute : Attribute
{
protected override Task HandleRequirementAsync(AuthorizationHandlerContext context, TRequirement requirement)
{
var attributes = new List<TAttribute>();
if (context.Resource is HttpContext httpContext)
{
var endPoint = httpContext.GetEndpoint();
var action = endPoint?.Metadata.GetMetadata<ControllerActionDescriptor>();
if(action != null)
{
attributes.AddRange(GetAttributes(action.ControllerTypeInfo.UnderlyingSystemType));
attributes.AddRange(GetAttributes(action.MethodInfo));
}
}
return HandleRequirementAsync(context, requirement, attributes);
}
protected abstract Task HandleRequirementAsync(AuthorizationHandlerContext context, TRequirement requirement, IEnumerable<TAttribute> attributes);
private static IEnumerable<TAttribute> GetAttributes(MemberInfo memberInfo) => memberInfo.GetCustomAttributes(typeof(TAttribute), false).Cast<TAttribute>();
}
Noting the way getting the ControllerActionDescriptor has changed.
I have bearer token and I can read claims.
I use that attribute on controllers and actions
public class CustomAuthorizationAttribute : ActionFilterAttribute
{
public string[] Claims;
public override void OnActionExecuting(ActionExecutingContext context)
{
// check user
var contextUser = context?.HttpContext?.User;
if (contextUser == null)
{
throw new BusinessException("Forbidden");
}
// check roles
var roles = contextUser.FindAll("http://schemas.microsoft.com/ws/2008/06/identity/claims/role").Select(c => c.Value).ToList();
if (!roles.Any(s => Claims.Contains(s)))
{
throw new BusinessException("Forbidden");
}
base.OnActionExecuting(context);
}
}
example
[CustomAuthorization(Claims = new string[]
{
nameof(AuthorizationRole.HR_ADMIN),
nameof(AuthorizationRole.HR_SETTING)
})]
[Route("api/[controller]")]
[ApiController]
public class SomeAdminController : ControllerBase
{
private readonly IMediator _mediator;
public SomeAdminController(IMediator mediator)
{
_mediator = mediator;
}
[HttpGet("list/SomeList")]
public async Task<IActionResult> SomeList()
=> Ok(await _mediator.Send(new SomeListQuery()));
}
That is Roles
public struct AuthorizationRole
{
public static string HR_ADMIN;
public static string HR_SETTING;
}
Here's a simple 5-step guide for how to implement custom role authorization using policies for all you copy and pasters out there :) . I used these docs.
Create a requirement:
public class RoleRequirement : IAuthorizationRequirement
{
public string Role { get; set; }
}
Create a handler:
public class RoleHandler : AuthorizationHandler<RoleRequirement>
{
protected override async Task HandleRequirementAsync(AuthorizationHandlerContext context, RoleRequirement requirement)
{
var requiredRole = requirement.Role;
//custom auth logic
// you can use context to access authenticated user,
// you can use dependecy injection to call custom services
var hasRole = true;
if (hasRole)
{
context.Succeed(requirement);
}
else
{
context.Fail(new AuthorizationFailureReason(this, $"Role {requirement.Role} missing"));
}
}
}
Add the handler in Program.cs:
builder.Services.AddSingleton<IAuthorizationHandler, RoleHandler>();
Add a policy with your role requirement in program.cs:
builder.Services.AddAuthorization(options =>
{
options.AddPolicy("Read", policy => policy.Requirements.Add(new RoleRequirement{Role = "ReadAccess_Custom_System"}));
});
Use your policy:
[Authorize("Read")]
public class ExampleController : ControllerBase
{
}
A lot of people here already told this, but with Policy handlers you can come really far in terms of what you could achieve with the old way in .NET Framework.
I followed a quick writeup from this answer on SO: https://stackoverflow.com/a/61963465/7081176
For me it works flawlessly after making some classes:
The EditUserRequirement:
public class EditUserRequirement : IAuthorizationRequirement
{
public EditUserRequirement()
{
}
}
An abstract handler to make my life easier:
public abstract class AbstractRequirementHandler<T> : IAuthorizationHandler
where T : IAuthorizationRequirement
{
public async Task HandleAsync(AuthorizationHandlerContext context)
{
var pendingRequirements = context.PendingRequirements.ToList();
foreach (var requirement in pendingRequirements)
{
if (requirement is T typedRequirement)
{
await HandleRequirementAsync(context, typedRequirement);
}
}
}
protected abstract Task HandleRequirementAsync(AuthorizationHandlerContext context, T requirement);
}
An implementation of the abstract handler:
public class EditUserRequirementHandler : AbstractRequirementHandler<EditUserRequirement>
{
protected override Task HandleRequirementAsync(AuthorizationHandlerContext context, EditUserRequirement requirement)
{
// If the user is owner of the resource, allow it.
if (IsOwner(context.User, g))
{
context.Succeed(requirement);
}
return Task.CompletedTask;
}
private static bool IsOwner(ClaimsPrincipal user, Guid userIdentifier)
{
return user.GetUserIdentifier() == userIdentifier;
}
}
Registering my handler and requirement:
services.AddSingleton<IAuthorizationHandler, EditUserRequirementHandler>();
services.AddAuthorization(options =>
{
options.AddPolicy(Policies.Policies.EditUser, policy =>
{
policy.Requirements.Add(new EditUserRequirement());
});
});
And then using my Policy in Blazor:
<AuthorizeView Policy="#Policies.EditUser" Resource="#id">
<NotAuthorized>
<Unauthorized />
</NotAuthorized>
<Authorized Context="Auth">
...
</Authorized>
</AuthorizeView>
I hope this is useful for anyone facing this issue.
I have been looking into solving a very similar issue, and settled on creating a custom ActionFilterAttribute (I'm going to call it AuthorizationFilterAttribute) instead of an AuthorizeAttribute to implement the guidance here: https://learn.microsoft.com/en-us/aspnet/core/security/authorization/resourcebased?view=aspnetcore-6.0#challenge-and-forbid-with-an-operational-resource-handler.
For authorization in our app. We had to call a service based on the parameters passed in authorization attribute.
For example, if we want to check if logged in doctor can view patient appointments we will pass "View_Appointment" to custom authorize attribute and check that right in DB service and based on results we will athorize. Here is the code for this scenario:
public class PatientAuthorizeAttribute : TypeFilterAttribute
{
public PatientAuthorizeAttribute(params PatientAccessRights[] right) : base(typeof(AuthFilter)) //PatientAccessRights is an enum
{
Arguments = new object[] { right };
}
private class AuthFilter : IActionFilter
{
PatientAccessRights[] right;
IAuthService authService;
public AuthFilter(IAuthService authService, PatientAccessRights[] right)
{
this.right = right;
this.authService = authService;
}
public void OnActionExecuted(ActionExecutedContext context)
{
}
public void OnActionExecuting(ActionExecutingContext context)
{
var allparameters = context.ActionArguments.Values;
if (allparameters.Count() == 1)
{
var param = allparameters.First();
if (typeof(IPatientRequest).IsAssignableFrom(param.GetType()))
{
IPatientRequest patientRequestInfo = (IPatientRequest)param;
PatientAccessRequest userAccessRequest = new PatientAccessRequest();
userAccessRequest.Rights = right;
userAccessRequest.MemberID = patientRequestInfo.PatientID;
var result = authService.CheckUserPatientAccess(userAccessRequest).Result; //this calls DB service to check from DB
if (result.Status == ReturnType.Failure)
{
//TODO: return apirepsonse
context.Result = new StatusCodeResult((int)System.Net.HttpStatusCode.Forbidden);
}
}
else
{
throw new AppSystemException("PatientAuthorizeAttribute not supported");
}
}
else
{
throw new AppSystemException("PatientAuthorizeAttribute not supported");
}
}
}
}
And on API action we use it like this:
[PatientAuthorize(PatientAccessRights.PATIENT_VIEW_APPOINTMENTS)] //this is enum, we can pass multiple
[HttpPost]
public SomeReturnType ViewAppointments()
{
}

Use custom validation responses with fluent validation

Hello I am trying to get custom validation response for my webApi using .NET Core.
Here I want to have response model like
[{
ErrorCode:
ErrorField:
ErrorMsg:
}]
I have a validator class and currently we just check ModalState.IsValid for validation Error and pass on the modelstate object as BadRequest.
But new requirement wants us to have ErrorCodes for each validation failure.
My sample Validator Class
public class TestModelValidator : AbstractValidator<TestModel>{
public TestModelValidator {
RuleFor(x=> x.Name).NotEmpty().WithErrorCode("1001");
RuleFor(x=> x.Age).NotEmpty().WithErrorCode("1002");
}
}
I can use something similar in my actions to get validation result
Opt1:
var validator = new TestModelValidator();
var result = validator.Validate(inputObj);
var errorList = result.Error;
and manipulate ValidationResult to my customn Response object.
or
Opt2:
I can use [CustomizeValidator] attribute and maybe an Interceptors.
but for Opt2 I don't know how to retrieve ValidationResult from interceptor to controller action.
All I want is to write a common method so that I avoid calling Opt1 in every controller action method for validation.
Request to point me to correct resource.
try with this:
services.Configure<ApiBehaviorOptions>(options =>
{
options.SuppressModelStateInvalidFilter = true;
});
I validate the model with fluentvalidation, after build the BadResquest response in a ActionFilter class:
public class ValidateModelStateAttribute : ActionFilterAttribute
{
public override void OnActionExecuting(ActionExecutingContext context)
{
if (!context.ModelState.IsValid)
{
var errors = context.ModelState.Values.Where(v => v.Errors.Count > 0)
.SelectMany(v => v.Errors)
.Select(v => v.ErrorMessage)
.ToList();
var responseObj = new
{
Message = "Bad Request",
Errors = errors
};
context.Result = new JsonResult(responseObj)
{
StatusCode = 400
};
}
}
}
In StartUp.cs:
services.AddMvc(options =>
{
options.Filters.Add(typeof(ValidateModelStateAttribute));
})
.AddFluentValidation(fvc => fvc.RegisterValidatorsFromAssemblyContaining<Startup>());
services.Configure<ApiBehaviorOptions>(options =>
{
options.SuppressModelStateInvalidFilter = true;
});
And it works fine. I hope you find it useful
As for me, it's better to use the following code in ASP.NET Core project
services.AddMvc().ConfigureApiBehaviorOptions(options =>
{
options.InvalidModelStateResponseFactory = c =>
{
var errors = string.Join('\n', c.ModelState.Values.Where(v => v.Errors.Count > 0)
.SelectMany(v => v.Errors)
.Select(v => v.ErrorMessage));
return new BadRequestObjectResult(new
{
ErrorCode = "Your validation error code",
Message = errors
});
};
});
Also take into account that instead of anonymous object you can use your concrete type. For example,
new BadRequestObjectResult(new ValidationErrorViewModel
{
ErrorCode = "Your validation error code",
Message = errors
});
In .net core you can use a combination of a IValidatorInterceptor to copy the ValidationResult to HttpContext.Items and then a ActionFilterAttribute to check for the result and return the custom response if it is found.
// If invalid add the ValidationResult to the HttpContext Items.
public class ValidatorInterceptor : IValidatorInterceptor {
public ValidationResult AfterMvcValidation(ControllerContext controllerContext, ValidationContext validationContext, ValidationResult result) {
if(!result.IsValid) {
controllerContext.HttpContext.Items.Add("ValidationResult", result);
}
return result;
}
public ValidationContext BeforeMvcValidation(ControllerContext controllerContext, ValidationContext validationContext) {
return validationContext;
}
}
// Check the HttpContext Items for the ValidationResult and return.
// a custom 400 error if it is found
public class ValidationResultAttribute : ActionFilterAttribute {
public override void OnActionExecuting(ActionExecutingContext ctx) {
if(!ctx.HttpContext.Items.TryGetValue("ValidationResult", out var value)) {
return;
}
if(!(value is ValidationResult vldResult)) {
return;
}
var model = vldResult.Errors.Select(err => new ValidationErrorModel(err)).ToArray();
ctx.Result = new BadRequestObjectResult(model);
}
}
// The custom error model now with 'ErrorCode'
public class ValidationErrorModel {
public string PropertyName { get; }
public string ErrorMessage { get; }
public object AttemptedValue { get; }
public string ErrorCode { get; }
public ValidationErrorModel(ValidationFailure error) {
PropertyName = error.PropertyName;
ErrorMessage = error.ErrorMessage;
AttemptedValue = error.AttemptedValue;
ErrorCode = error.ErrorCode;
}
}
Then in Startup.cs you can register the ValidatorInterceptor and ValidationResultAttribute like so:
public class Startup {
public void ConfigureServices(IServiceCollection services) {
services.AddTransient<IValidatorInterceptor, ValidatorInterceptor>();
services.AddMvc(o => {
o.Filters.Add<ValidateModelAttribute>()
});
}
}
Refer this link for answer: https://github.com/JeremySkinner/FluentValidation/issues/548
Solution:
What I've done is that I created a basevalidator class which inherited both IValidatorInterceptor and AbstractValidator. In afterMvcvalidation method if validation is not successful, I map the error from validationResult to my custom response object and throw Custom exception which I catch in my exception handling middleware and return response.
On Serialization issue where controller gets null object:
modelstate.IsValid will be set to false when Json Deserialization fails during model binding and Error details will be stored in ModelState. [Which is what happened in my case]
Also due to this failure, Deserialization does not continue further and gets null object in controller method.
As of now, I have created a hack by setting serialization errorcontext.Handled = true manually and allowing my fluentvalidation to catch the invalid input.
https://www.newtonsoft.com/json/help/html/SerializationErrorHandling.htm [defined OnErrorAttribute in my request model].
I am searching for a better solution but for now this hack is doing the job.
Similar to Alexander's answer above, I created an anonymous object using the original factory I could find in the source code, but just changed out the parts to give back a custom HTTP response code (422 in my case).
ApiBehaviorOptionsSetup (Original factory)
services.AddMvcCore()
...
// other builder methods here
...
.ConfigureApiBehaviorOptions(options =>
{
// Replace the built-in ASP.NET InvalidModelStateResponse to use our custom response code
options.InvalidModelStateResponseFactory = context =>
{
var problemDetailsFactory = context.HttpContext.RequestServices.GetRequiredService<ProblemDetailsFactory>();
var problemDetails = problemDetailsFactory.CreateValidationProblemDetails(context.HttpContext, context.ModelState, statusCode: 422);
var result = new UnprocessableEntityObjectResult(problemDetails);
result.ContentTypes.Add("application/problem+json");
result.ContentTypes.Add("application/problem+xml");
return result;
};
});
Here I tried
public async Task OnActionExecutionAsync(ActionExecutingContext context,
ActionExecutionDelegate next)
{
if (!context.ModelState.IsValid)
{
var errors = context.ModelState.Values.Where(v => v.Errors.Count > 0)
.SelectMany(v => v.Errors)
.Select(v => v.ErrorMessage)
.ToList();
var value = context.ModelState.Keys.ToList();
Dictionary<string, string[]> dictionary = new Dictionary<string, string[]>();
foreach (var modelStateKey in context.ModelState.Keys.ToList())
{
string[] arr = null ;
List<string> list = new List<string>();
foreach (var error in context.ModelState[modelStateKey].Errors)
{
list.Add(error.ErrorMessage);
}
arr = list.ToArray();
dictionary.Add(modelStateKey, arr);
}
var responseObj = new
{
StatusCode="400",
Message = "Bad Request",
Errors = dictionary
};
context.Result = new BadRequestObjectResult(responseObj);
return;
}
await next();
}
Response Model:
{
"statusCode": "400",
"message": "Bad Request",
"errors": {
"Channel": [
"'Channel' must not be empty."
],
"TransactionId": [
"'TransactionId' must not be empty."
],
"Number": [
"'Number' must not be empty."
]
}
}

C# API Controller Custom Filter with HttpActionContext Redirect to controller?

Is there a way to create a custom filter with an API controller to redirect to a MVC controller?
After looking around a bit his is what i have.
public class APIHasOneOfThesePermissions : ActionFilterAttribute
{
protected UserManager<ApplicationUser> UserManager { get; set; }
private SAMPortal.DAL.SAMPortalContext db = new DAL.SAMPortalContext();
public string[] Permissions { get; set; }
public APIHasOneOfThesePermissions(string[] Permissions)
{
this.UserManager = new UserManager<ApplicationUser>(new UserStore<ApplicationUser>(this.db));
this.Permissions = Permissions;
}
public override void OnActionExecuting(HttpActionContext filterContext)
{
string userID = HttpContext.Current.User.Identity.GetUserId();
var CurrUser = db.Users.Include(u => u.Role.Permissions).Where(user => user.Id.Equals(userID)).FirstOrDefault();
bool hasPermission = false;
foreach (string x in Permissions)
{
if (hasPermission == false)
{
hasPermission = CurrUser.HasPermission(x);
}
}
if (hasPermission == false)
{
filterContext.Response = new HttpResponseMessage(HttpStatusCode.Unauthorized);
}
base.OnActionExecuting(filterContext);
}
}
However when i execute the code it doesn't redirect them to the error page. Ideally i would like to redirect to a specify non-API controller is that possible?
I've created AuthorizeRedirectAttribute in one of my projects like this:
using System;
using System.Net;
using System.Web.Mvc;
namespace MyNamespace.Attributes
{
[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method)]
public class AuthorizeRedirectAttribute : AuthorizeAttribute
{
public string RedirectUrl = "~/Error/Forbidden403";
public override void OnAuthorization(AuthorizationContext filterContext)
{
base.OnAuthorization(filterContext);
}
protected override void HandleUnauthorizedRequest(AuthorizationContext filterContext)
{
base.HandleUnauthorizedRequest(filterContext);
var httpContext = filterContext.RequestContext.HttpContext;
var request = httpContext.Request;
var response = httpContext.Response;
// If AJAX request, just return appropriate code
if (request.IsAjaxRequest())
{
if (filterContext.HttpContext.User.Identity.IsAuthenticated)
response.StatusCode = (int)HttpStatusCode.Forbidden;
else
response.StatusCode = (int)HttpStatusCode.Unauthorized;
response.SuppressFormsAuthenticationRedirect = true;
response.End();
}
// Otherwise check if authenticated, and if not redirect to specified url
if (httpContext.User.Identity.IsAuthenticated)
{
httpContext.Response.Redirect(RedirectUrl);
}
}
}
}
Then I've used it like this
[AuthorizeRedirect(Roles = "Administrator")]
public class MyController : Controller
{
}
In this case I've decorated whole controller with this attribute. It can also be applied to single controller function, if necessary. Basically what it does is, it checks whether logged on user is in role Administrator. If it is not, user is redirected to "~/Error/Forbidden403" action (returning simple view displaying user has not enough permissions). Hope it helps.
You could also implement checking your own permissions, as you did in your code.

Return JSON with error status code MVC

I was trying to return an error to the call to the controller as advised in
This link so that client can take appropriate action.
The controller is called by javascript via jquery AJAX. I am getting the Json object back only if I don't set the status to error.
Here is the sample code
if (response.errors.Length > 0)
Response.StatusCode = (int)HttpStatusCode.BadRequest;
return Json(response);
I get the Json if I don't set the statuscode.
If I set the status code I get the status code back but not the Json error object.
Update
I want to send an Error object as JSON so that it can be handled error callback of ajax.
The neatest solution I've found is to create your own JsonResult that extends the original implementation and allows you to specify a HttpStatusCode:
public class JsonHttpStatusResult : JsonResult
{
private readonly HttpStatusCode _httpStatus;
public JsonHttpStatusResult(object data, HttpStatusCode httpStatus)
{
Data = data;
_httpStatus = httpStatus;
}
public override void ExecuteResult(ControllerContext context)
{
context.RequestContext.HttpContext.Response.StatusCode = (int)_httpStatus;
base.ExecuteResult(context);
}
}
You can then use this in your controller action like so:
if(thereWereErrors)
{
var errorModel = new { error = "There was an error" };
return new JsonHttpStatusResult(errorModel, HttpStatusCode.InternalServerError);
}
I found the solution here
I had to create a action filter to override the default behaviour of MVC
Here is my exception class
class ValidationException : ApplicationException
{
public JsonResult exceptionDetails;
public ValidationException(JsonResult exceptionDetails)
{
this.exceptionDetails = exceptionDetails;
}
public ValidationException(string message) : base(message) { }
public ValidationException(string message, Exception inner) : base(message, inner) { }
protected ValidationException(
System.Runtime.Serialization.SerializationInfo info,
System.Runtime.Serialization.StreamingContext context)
: base(info, context) { }
}
Note that I have constructor which initializes my JSON. Here is the action filter
public class HandleUIExceptionAttribute : FilterAttribute, IExceptionFilter
{
public virtual void OnException(ExceptionContext filterContext)
{
if (filterContext == null)
{
throw new ArgumentNullException("filterContext");
}
if (filterContext.Exception != null)
{
filterContext.ExceptionHandled = true;
filterContext.HttpContext.Response.Clear();
filterContext.HttpContext.Response.TrySkipIisCustomErrors = true;
filterContext.HttpContext.Response.StatusCode = (int)System.Net.HttpStatusCode.InternalServerError;
filterContext.Result = ((ValidationException)filterContext.Exception).myJsonError;
}
}
Now that I have the action filter, I will decorate my controller with the filter attribute
[HandleUIException]
public JsonResult UpdateName(string objectToUpdate)
{
var response = myClient.ValidateObject(objectToUpdate);
if (response.errors.Length > 0)
throw new ValidationException(Json(response));
}
When the error is thrown the action filter which implements IExceptionFilter get called and I get back the Json on the client on error callback.
There is a very elegant solution to this problem, just configure your site via web.config:
<system.webServer>
<httpErrors errorMode="DetailedLocalOnly" existingResponse="PassThrough"/>
</system.webServer>
Source: https://serverfault.com/questions/123729/iis-is-overriding-my-response-content-if-i-manually-set-the-response-statuscode
A simple way to send a error to Json is control Http Status Code of response object and set a custom error message.
Controller
public JsonResult Create(MyObject myObject)
{
//AllFine
return Json(new { IsCreated = True, Content = ViewGenerator(myObject));
//Use input may be wrong but nothing crashed
return Json(new { IsCreated = False, Content = ViewGenerator(myObject));
//Error
Response.StatusCode = (int)HttpStatusCode.InternalServerError;
return Json(new { IsCreated = false, ErrorMessage = 'My error message');
}
JS
$.ajax({
type: "POST",
dataType: "json",
url: "MyController/Create",
data: JSON.stringify(myObject),
success: function (result) {
if(result.IsCreated)
{
//... ALL FINE
}
else
{
//... Use input may be wrong but nothing crashed
}
},
error: function (error) {
alert("Error:" + erro.responseJSON.ErrorMessage ); //Error
}
});
Building on the answer from Richard Garside, here's the ASP.Net Core version
public class JsonErrorResult : JsonResult
{
private readonly HttpStatusCode _statusCode;
public JsonErrorResult(object json) : this(json, HttpStatusCode.InternalServerError)
{
}
public JsonErrorResult(object json, HttpStatusCode statusCode) : base(json)
{
_statusCode = statusCode;
}
public override void ExecuteResult(ActionContext context)
{
context.HttpContext.Response.StatusCode = (int)_statusCode;
base.ExecuteResult(context);
}
public override Task ExecuteResultAsync(ActionContext context)
{
context.HttpContext.Response.StatusCode = (int)_statusCode;
return base.ExecuteResultAsync(context);
}
}
Then in your controller, return as follows:
// Set a json object to return. The status code defaults to 500
return new JsonErrorResult(new { message = "Sorry, an internal error occurred."});
// Or you can override the status code
return new JsonErrorResult(new { foo = "bar"}, HttpStatusCode.NotFound);
The thing that worked for me (and that I took from another stackoverflow response), is to set the flag:
Response.TrySkipIisCustomErrors = true;
You have to return JSON error object yourself after setting the StatusCode, like so ...
if (BadRequest)
{
Dictionary<string, object> error = new Dictionary<string, object>();
error.Add("ErrorCode", -1);
error.Add("ErrorMessage", "Something really bad happened");
return Json(error);
}
Another way is to have a JsonErrorModel and populate it
public class JsonErrorModel
{
public int ErrorCode { get; set;}
public string ErrorMessage { get; set; }
}
public ActionResult SomeMethod()
{
if (BadRequest)
{
var error = new JsonErrorModel
{
ErrorCode = -1,
ErrorMessage = "Something really bad happened"
};
return Json(error);
}
//Return valid response
}
Take a look at the answer here as well
You need to decide if you want "HTTP level error" (that what error codes are for) or "application level error" (that what your custom JSON response is for).
Most high level objects using HTTP will never look into response stream if error code set to something that is not 2xx (success range). In your case you are explicitly setting error code to failure (I think 403 or 500) and force XMLHttp object to ignore body of the response.
To fix - either handle error conditions on client side or not set error code and return JSON with error information (see Sbossb reply for details).
Several of the responses rely on an exception being thrown and having it handled in the OnException override. In my case, I wanted to return statuses such as bad request if the user, say, had passed in a bad ID. What works for me is to use the ControllerContext:
var jsonResult = new JsonResult { JsonRequestBehavior = JsonRequestBehavior.AllowGet, Data = "whoops" };
ControllerContext.HttpContext.Response.StatusCode = (int)HttpStatusCode.BadRequest;
return jsonResult;
And if your needs aren't as complex as Sarath's you can get away with something even simpler:
[MyError]
public JsonResult Error(string objectToUpdate)
{
throw new Exception("ERROR!");
}
public class MyErrorAttribute : FilterAttribute, IExceptionFilter
{
public virtual void OnException(ExceptionContext filterContext)
{
if (filterContext == null)
{
throw new ArgumentNullException("filterContext");
}
if (filterContext.Exception != null)
{
filterContext.ExceptionHandled = true;
filterContext.HttpContext.Response.Clear();
filterContext.HttpContext.Response.TrySkipIisCustomErrors = true;
filterContext.HttpContext.Response.StatusCode = (int)System.Net.HttpStatusCode.InternalServerError;
filterContext.Result = new JsonResult() { Data = filterContext.Exception.Message };
}
}
}
If you are just using MVC the simplest way is to use HttpStatusCodeResult.
public ActionResult MyAjaxRequest(string args)
{
string error_message = string.Empty;
try
{
// successful
return Json(args);
}
catch (Exception e)
{
error_message = e.Message;
}
return new HttpStatusCodeResult(500, error_message);
}
When the error is returned to the client you can display it or action it how you like.
request.fail(function (jqXHR) {
if (jqXHR.status == 500) {
alert(jqXHR.statusText);
}
})
I was running Asp.Net Web Api 5.2.7 and it looks like the JsonResult class has changed to use generics and an asynchronous execute method. I ended up altering Richard Garside's solution:
public class JsonHttpStatusResult<T> : JsonResult<T>
{
private readonly HttpStatusCode _httpStatus;
public JsonHttpStatusResult(T content, JsonSerializerSettings serializer, Encoding encoding, ApiController controller, HttpStatusCode httpStatus)
: base(content, serializer, encoding, controller)
{
_httpStatus = httpStatus;
}
public override Task<HttpResponseMessage> ExecuteAsync(CancellationToken cancellationToken)
{
var returnTask = base.ExecuteAsync(cancellationToken);
returnTask.Result.StatusCode = HttpStatusCode.BadRequest;
return returnTask;
}
}
Following Richard's example, you could then use this class like this:
if(thereWereErrors)
{
var errorModel = new CustomErrorModel("There was an error");
return new JsonHttpStatusResult<CustomErrorModel>(errorModel, new JsonSerializerSettings(), new UTF8Encoding(), this, HttpStatusCode.InternalServerError);
}
Unfortunately, you can't use an anonymous type for the content, as you need to pass a concrete type (ex: CustomErrorType) to the JsonHttpStatusResult initializer. If you want to use anonymous types, or you just want to be really slick, you can build on this solution by subclassing ApiController to add an HttpStatusCode param to the Json methods :)
public abstract class MyApiController : ApiController
{
protected internal virtual JsonHttpStatusResult<T> Json<T>(T content, HttpStatusCode httpStatus, JsonSerializerSettings serializerSettings, Encoding encoding)
{
return new JsonHttpStatusResult<T>(content, httpStatus, serializerSettings, encoding, this);
}
protected internal JsonHttpStatusResult<T> Json<T>(T content, HttpStatusCode httpStatus, JsonSerializerSettings serializerSettings)
{
return Json(content, httpStatus, serializerSettings, new UTF8Encoding());
}
protected internal JsonHttpStatusResult<T> Json<T>(T content, HttpStatusCode httpStatus)
{
return Json(content, httpStatus, new JsonSerializerSettings());
}
}
Then you can use it with an anonymous type like this:
if(thereWereErrors)
{
var errorModel = new { error = "There was an error" };
return Json(errorModel, HttpStatusCode.InternalServerError);
}
Here is the JsonResult override answer for ASP.NET v5+ . I have tested and it works just as well as in earlier versions.
public class JsonHttpStatusResult : JsonResult
{
private readonly HttpStatusCode _httpStatus;
public JsonHttpStatusResult(object data, HttpStatusCode httpStatus) : base(data)
{
_httpStatus = httpStatus;
}
public override Task ExecuteResultAsync(ActionContext context)
{
context.HttpContext.Response.StatusCode = (int)_httpStatus;
if (context == null)
{
throw new ArgumentNullException(nameof(context));
}
var services = context.HttpContext.RequestServices;
var executor = services.GetRequiredService<IActionResultExecutor<JsonResult>>();
return executor.ExecuteAsync(context, this);
}
}

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