Felix Felix - 2 months ago 91x
ASP.NET (C#) Question

ASP.NET Core Web API Authentication

I'm struggling with how to set up authentication in my web service.
The service is build with the ASP.NET Core web api.

All my clients (WPF applications) should use the same credentials to call the web service methods.

After same research, I came up with basic authentication - sending a username and password in the header of the HTTP request.
But after hours of research, it seems to me that basic authentication is not the way to go in ASP.NET Core.

Most of the resources I found are implementing authentication using OAuth or some other middleware. But that seems to be oversized for my scenario, as well as using the Identity part of ASP.NET Core.

So what is the right way to achieve my goal - simple authentication with username and password in a ASP.NET Core web service?

Thanks in advance!


You can implement a middleware which handles Basic authentication.

public async Task Invoke(HttpContext context)
    var authHeader = context.Request.Headers.Get("Authorization");
    if (authHeader != null && authHeader.StartsWith("basic", StringComparison.OrdinalIgnoreCase))
        var token = authHeader.Substring("Basic ".Length).Trim();
        var credentialstring = Encoding.UTF8.GetString(Convert.FromBase64String(token));
        var credentials = credentialstring.Split(':');
        if(credentials[0] == "admin" && credentials[1] == "admin")
            var claims = new[] { new Claim("name", credentials[0]), new Claim(ClaimTypes.Role, "Admin") };
            var identity = new ClaimsIdentity(claims, "Basic");
            context.User = new ClaimsPrincipal(identity);
        context.Response.StatusCode = 401;
        context.Response.Headers.Set("WWW-Authenticate", "Basic realm=\"dotnetthoughts.net\"");
    await _next(context);

This code is written in a beta version of asp.net core. Hope it helps.