ASP.NET how to get claims from shared cookie

Question

I have several asp.net Web API microservices and I want to use the so called single sign in operation using Cookie. So when I sign in in my Identity API all other APIs would know who is signed in.

Now - several questions popped when doing so: I am using this method (and Identity SignInManager method PasswordSignInAsync) :

builder.Services.ConfigureApplicationCookie(config =>
{
    config.Cookie.Name = "Identity.Cookie";
    config.LoginPath = "/User/Login";
    config.LogoutPath = "/User/Logout";
});

...to log in and produce the cookie.

Now, I searched on the topic how to share this cookie among other APIs, but I was shocked to find out that this cookie actually gets shared. And I do not have any specific functionality for cookie sharing. Here are screenshots of my 2 APIs running on different ports, both having the same cookie. I even compared their value and its the same. The APIs are in the same solution.

Now, the questions are 2 - why is this cookie shared among the APIs and how can I read the information for the logged user (claims) from it?

I tried to use CookieHandler abstract class which has 3 abstract methods. But the problem was that these methods had HttpContext parameter coming from System.Web namespace, whereas the HttpContext property comes from AspNetCore.Mvc.

Any advise would be appreciated, since I have no idea how to get the Identities from the cookie. Bear in mind that only the Identity.API has SignInManager/ UserManager.

Rouzbeh Zarandi · Answer

the cookie you assign to logged in user must have information about the user claims and the scopes that user can access.

in general after login the user get the cookie or cookies that include the access_token which has the data on claims and scopes he/she can access to.
after login when user call an api this access token is included in the header of the request so the api will extract information in asp.net middle ware pipeline and then check if this request authorized to use the resources.

if you are using identity server, in client configuration set AlwaysIncludeUserClaimsInIdToken = true and the claims for the user is accessible from profile stored in access token. i dont know if you are using identity server or not so i can not go further. if you are using only identity implementation then please take look at api security with Oauth.

ASP.NET how to get claims from shared cookie

1 Answers