Deployment and Proxy Trust

dotnet publish -c Release -f net10.0 --self-contained false

This command is not executed; no application artifact is published or deployed.

using System;
using System.Net;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.HttpOverrides;
using Microsoft.Extensions.Logging.Abstractions;
using Microsoft.Extensions.Options;

var options = new ForwardedHeadersOptions { ForwardedHeaders = ForwardedHeaders.XForwardedProto };
options.KnownProxies.Add(IPAddress.Parse("192.0.2.10"));
var middleware = new ForwardedHeadersMiddleware(_ => Task.CompletedTask, NullLoggerFactory.Instance, Options.Create(options));
string untrusted = await CheckAsync("203.0.113.7");
string trusted = await CheckAsync("192.0.2.10");
Console.WriteLine($"untrusted={untrusted} trusted={trusted}");

async Task<string> CheckAsync(string peer)
{
    var context = new DefaultHttpContext();
    context.Connection.RemoteIpAddress = IPAddress.Parse(peer);
    context.Request.Scheme = "http";
    context.Request.Headers["X-Forwarded-Proto"] = "https";
    await middleware.Invoke(context);
    return context.Request.Scheme;
}

untrusted=http trusted=https

Only the configured synthetic proxy changes scheme; the test opens no listener or connection.