ASP .net core jwt authentication with proxy

Question

I'm implementing an asp .net core web API for my company. The authentication should be processed via the built-in jwt bearer authentication.

The problem I'm struggling with is, that I'm working behind a proxy. So for the token validation, I'm facing 407 proxy authentication failed responses.

As far as I know, in .net framework, there was the possibility to define a default proxy in the web.config but for .net core, I couldn't find any similar functionality.

Is it possible to "inject" proxy settings for the jwt authentication or if not, is there any other way to work with this authentication behind a proxy?

Answer 1

The option to define a global proxy in the Web.config is gone for ASP.NET Core.

Most APIs that do anything over HTTP allow you to set a HttpMessageHandler, though. You can set the proxy for that MessageHandler.

For instance, assuming you're using default JwtBearer Authentication you could try this approach:

appsettings.json:

"Proxy": {
    "ProxyAddress": "http://MyProxy:8080"
  },

In your ConfigureServices method you can then:

services.AddAuthentication()
   .AddJwtBearer("Bearer", o =>
   {
      o.BackchannelHttpHandler = new HttpClientHandler
      {
         Proxy = new WebProxy(Configuration["Proxy:ProxyAddress"])
      };
  });

Depending on what flow you use you may need to set the Proxy on other/additional handlers as well. Additionally, if you require finer grained control over the Proxy, you can always write a class implementing IWebProxy and use that instead of newing a WebProxy with a proxy address.