ersatztv/ErsatzTV.Tests/Controllers/ApiControllerSecurityTests.cs

using System.Reflection;
using ErsatzTV;
using ErsatzTV.Controllers.Api;
using ErsatzTV.Filters;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.Routing;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.FileProviders;
using Microsoft.Extensions.Options;
using NSubstitute;
using NUnit.Framework;
using Shouldly;

namespace ErsatzTV.Tests.Controllers;

[TestFixture]
public class ApiControllerSecurityTests
{
    private static readonly bool ApiKeyAuthorizationFilterIsGlobal = IsApiKeyAuthorizationFilterRegisteredGlobally();

    [Test]
    public void Every_Mutating_Api_Action_Should_Be_Globally_Protected_Or_Explicitly_Exempt()
    {
        // Scan the assembly instead of hand-maintaining a list of controllers here: a
        // hardcoded array silently drifts as new controllers are added (9 were missing at
        // one point, including two with real mutating actions - ArtworkUploadController POST
        // and ChannelTemplateController POST/PUT/DELETE - that were never actually checked).
        // Note: not every controller in this namespace derives from ControllerBase (e.g.
        // ChannelController, ScannerController, SessionController, MaintenanceController,
        // TroubleshootController) - filter on [ApiController] + concrete class only, matching
        // the pattern already used by ScannerController_Should_Be_Only_Api_Key_Exempt_Api_Controller
        // below, so those controllers stay covered rather than silently dropping out of the scan.
        Type[] apiControllers = typeof(CollectionController)
            .Assembly
            .GetTypes()
            .Where(t => t.Namespace == typeof(CollectionController).Namespace)
            .Where(t => t is { IsClass: true, IsAbstract: false })
            .Where(t => t.GetCustomAttributes<ApiControllerAttribute>(inherit: true).Any())
            .ToArray();

        // Guard against the scan silently matching nothing (e.g. a namespace rename) and
        // giving this test a false pass.
        apiControllers.Length.ShouldBeGreaterThanOrEqualTo(20);

        foreach (Type controllerType in apiControllers)
        {
            bool controllerSkipsApiKey = controllerType
                .GetCustomAttributes<SkipApiKeyAuthorizationAttribute>(inherit: true)
                .Any();

            foreach (MethodInfo action in controllerType
                         .GetMethods(BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly))
            {
                bool isMutating = action
                    .GetCustomAttributes<HttpMethodAttribute>(inherit: true)
                    .SelectMany(a => a.HttpMethods)
                    .Any(m => m is "POST" or "PUT" or "PATCH" or "DELETE");

                if (!isMutating)
                {
                    continue;
                }

                bool actionSkipsApiKey = action
                    .GetCustomAttributes<SkipApiKeyAuthorizationAttribute>(inherit: true)
                    .Any();

                (controllerSkipsApiKey || actionSkipsApiKey || IsGloballyProtected())
                    .ShouldBeTrue($"{controllerType.Name}.{action.Name} must be covered by global API write auth or explicitly exempt");
            }
        }
    }

    [Test]
    public void ScannerController_Should_Be_Only_Api_Key_Exempt_Api_Controller()
    {
        Type[] exemptControllers = typeof(ScannerController)
            .Assembly
            .GetTypes()
            .Where(t => t.Namespace == typeof(ScannerController).Namespace)
            .Where(t => t.GetCustomAttributes<ApiControllerAttribute>(inherit: true).Any())
            .Where(t => t.GetCustomAttributes<SkipApiKeyAuthorizationAttribute>(inherit: true).Any())
            .ToArray();

        exemptControllers.ShouldBe([typeof(ScannerController)]);
    }

    [Test]
    public void Startup_Should_Register_ApiKeyAuthorizationFilter_Globally()
    {
        ApiKeyAuthorizationFilterIsGlobal.ShouldBeTrue();
    }

    private static bool IsGloballyProtected() => ApiKeyAuthorizationFilterIsGlobal;

    private static bool IsApiKeyAuthorizationFilterRegisteredGlobally()
    {
        var settings = new Dictionary<string, string?>
        {
            ["provider"] = "sqlite",
            ["ConnectionStrings:Data"] = "Data Source=:memory:"
        };

        IConfiguration configuration = new ConfigurationBuilder()
            .AddInMemoryCollection(settings)
            .Build();

        var environment = Substitute.For<IWebHostEnvironment>();
        environment.ApplicationName.Returns("ErsatzTV");
        environment.EnvironmentName.Returns("Development");
        environment.ContentRootPath.Returns(TestContext.CurrentContext.TestDirectory);
        environment.WebRootPath.Returns(TestContext.CurrentContext.TestDirectory);
        environment.ContentRootFileProvider.Returns(new NullFileProvider());
        environment.WebRootFileProvider.Returns(new NullFileProvider());

        var services = new ServiceCollection();
        new Startup(configuration, environment).ConfigureServices(services);

        using ServiceProvider provider = services.BuildServiceProvider();
        MvcOptions options = provider.GetRequiredService<IOptions<MvcOptions>>().Value;

        return options.Filters
            .OfType<ServiceFilterAttribute>()
            .Any(a => a.ServiceType == typeof(ApiKeyAuthorizationFilter));
    }
}