Connecting Azure Active Directory with .NET Web Api, authenticated is always false - azure

Question

I am developing a Standard .NET Web Api 2 with Angular 7 and I need to connect Azure Active Directory.
I have added this code:
public static void ConfigureAuth(IAppBuilder app)
{
app.UseWindowsAzureActiveDirectoryBearerAuthentication(
new WindowsAzureActiveDirectoryBearerAuthenticationOptions
{
Tenant = configurationManager.AadTenant,
TokenValidationParameters = new TokenValidationParameters
{
ValidAudience = configurationManager.AadAudience,
},
});
}
Both my Tenant and Audience are correct. Everything works fine and the token is valid and exists in the request.
The problem is that IsAuthenticated is always false and when I looked inside the claims in the identity they were empty
protected override bool IsAuthorized(HttpActionContext actionContext)
{
return base.IsAuthorized(actionContext); // Always false
}
I don't know where the problem is. I have tried many links but none of them worked for me. Anybody knows why? Thanks

Answer 1

To protect your service, you can use IsAuthorize filter implementation something like below:
private static string trustedCallerClientId = ConfigurationManager.AppSettings["ida:TrustedCallerClientId"];
protected override bool IsAuthorized(HttpActionContext actionContext)
{
bool isAuthenticated = false;
try
{
string currentCallerClientId = ClaimsPrincipal.Current.FindFirst("appid").Value;
isAuthenticated = currentCallerClientId == trustedCallerClientId;
}
catch (Exception ex)
{
new CustomLogger().LogError(ex, "Invalid User");
isAuthenticated = false;
}
return isAuthenticated;
}
The principal is not taken from the current thread, but from the actionContext. So, what you must set is the principal in the request context of the action context:
actionContext.RequestContext.Principal = yourPrincipal;
I am assuming your action context.requestcontext does not have the right data, that''s why even though your request are succeeding but your attribute is always false.
Reference:
https://www.c-sharpcorner.com/article/azure-active-directory-authentication/
Hope it helps.