ASP.NET CORE 1.0, Impersonation

Question

I'm writing an Intranet application. Target framework in project.json is dnx451. That's my publishing command:

dnu publish --runtime dnx-clr-win-x86.1.0.0-rc1-update1 --no-source

Database Connection string:

Server=name;Database=name;Trusted_Connection=True;

I'm trying to impersonate the database access but it's not working. When I start the application my windows user is recognized and it says Hello, Domain\Username on top right. As soon as I try to access the database I get the error "Login failed for user Domain\Computername". If I run the application pool under my user then everything works fine.

IIS: .NET CLR Versio is v4.0, Managed Pipline Mode Classic and Identity is ApplicationPoolIdentity. Website authentications: ASP.NET Impersonation and Windows Authentication are enabled.

What do I need to change that impersonation is finally working?

Answer 1

Core does not support impersonation because all web code is out of proc, hosted by Kestrel. If you want to do it you need to take the current Principal, as a WindowsPrincipal, then manually impersonate at the point where you need it.

One thing to note is that in RC1 you don't get a WindowsPrincipal, so you can't do this right now. It'll be fixed in RC2.

Answer 2

If you want every page request to impersonate the user, you can configure your own Middleware to run before MVC;

public class Impersonate
{
    private readonly RequestDelegate next;
    public Impersonate(RequestDelegate next) {
        this.next = next;
    }
    public async Task Invoke(HttpContext context) {
        var winIdent = context.User.Identity as WindowsIdentity;
        if (winIdent == null) {
            await next.Invoke(context);
        }else {
            WindowsIdentity.RunImpersonated(winIdent.AccessToken, () => {
                next.Invoke(context).Wait();
            });
        }
    }
}

public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory) {
    ....
    app.UseMiddleware<Impersonate>();
    app.UseMvc(...);
    ...
}