Add compat switch to opt out of breaking change in AuthZ (#23324)

src/Security/Authorization/Policy/src/AuthorizationMiddleware.cs

@@ -11,6 +11,9 @@ namespace Microsoft.AspNetCore.Authorization
 {
     public class AuthorizationMiddleware
     {
+        // AppContext switch used to control whether HttpContext or endpoint is passed as a resource to AuthZ
+        private const string SuppressUseHttpContextAsAuthorizationResource = "Microsoft.AspNetCore.Authorization.SuppressUseHttpContextAsAuthorizationResource";
+
         // Property key is used by Endpoint routing to determine if Authorization has run
         private const string AuthorizationMiddlewareInvokedWithEndpointKey = "__AuthorizationMiddlewareWithEndpointInvoked";
         private static readonly object AuthorizationMiddlewareWithEndpointInvokedValue = new object();
@@ -18,7 +21,7 @@ namespace Microsoft.AspNetCore.Authorization
         private readonly RequestDelegate _next;
         private readonly IAuthorizationPolicyProvider _policyProvider;
 
-        public AuthorizationMiddleware(RequestDelegate next, IAuthorizationPolicyProvider policyProvider)
+        public AuthorizationMiddleware(RequestDelegate next, IAuthorizationPolicyProvider policyProvider) 
         {
             _next = next ?? throw new ArgumentNullException(nameof(next));
             _policyProvider = policyProvider ?? throw new ArgumentNullException(nameof(policyProvider));
@@ -61,8 +64,17 @@ namespace Microsoft.AspNetCore.Authorization
                 return;
             }
 
-            var authorizeResult = await policyEvaluator.AuthorizeAsync(policy, authenticateResult, context, resource: context);
-
+            object? resource;
+            if (AppContext.TryGetSwitch(SuppressUseHttpContextAsAuthorizationResource, out var useEndpointAsResource) && useEndpointAsResource)
+            {
+                resource = endpoint;
+            }
+            else
+            {
+                resource = context;
+            }
+            
+            var authorizeResult = await policyEvaluator.AuthorizeAsync(policy, authenticateResult, context, resource);
             var authorizationMiddlewareResultHandler = context.RequestServices.GetRequiredService<IAuthorizationMiddlewareResultHandler>();
             await authorizationMiddlewareResultHandler.HandleAsync(_next, context, policy, authorizeResult);
         }

src/Security/Authorization/test/AuthorizationMiddlewareTests.cs

@@ -9,6 +9,7 @@ using Microsoft.AspNetCore.Authorization.Policy;
 using Microsoft.AspNetCore.Authorization.Test.TestObjects;
 using Microsoft.AspNetCore.Http;
 using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Options;
 using Moq;
 using Xunit;
 
@@ -314,7 +315,7 @@ namespace Microsoft.AspNetCore.Authorization.Test
         }
 
         [Fact]
-        public async Task AuthZResourceShouldBeHttpContextAndHaveHEndpoint()
+        public async Task AuthZResourceCanBeHttpContextAndHaveEndpoint()
         {
             // Arrange
             HttpContext resource = null;
@@ -340,6 +341,33 @@ namespace Microsoft.AspNetCore.Authorization.Test
             Assert.Equal(endpoint, resource.GetEndpoint());
         }
 
+        [Fact]
+        public async Task AuthZResourceShouldBeEndpointByDefaultWithCompatSwitch()
+        {
+            AppContext.SetSwitch("Microsoft.AspNetCore.Authorization.SuppressUseHttpContextAsAuthorizationResource", isEnabled: true);
+
+            // Arrange
+            object resource = null;
+            var policy = new AuthorizationPolicyBuilder().RequireAssertion(c =>
+            {
+                resource = c.Resource;
+                return true;
+            }).Build();
+            var policyProvider = new Mock<IAuthorizationPolicyProvider>();
+            policyProvider.Setup(p => p.GetDefaultPolicyAsync()).ReturnsAsync(policy);
+            var next = new TestRequestDelegate();
+
+            var middleware = CreateMiddleware(next.Invoke, policyProvider.Object);
+            var endpoint = CreateEndpoint(new AuthorizeAttribute());
+            var context = GetHttpContext(endpoint: endpoint);
+
+            // Act
+            await middleware.Invoke(context);
+
+            // Assert
+            Assert.Equal(endpoint, resource);
+        }
+        
         [Fact]
         public async Task Invoke_RequireUnknownRoleShouldForbid()
         {
@@ -410,7 +438,6 @@ namespace Microsoft.AspNetCore.Authorization.Test
         private AuthorizationMiddleware CreateMiddleware(RequestDelegate requestDelegate = null, IAuthorizationPolicyProvider policyProvider = null)
         {
             requestDelegate = requestDelegate ?? ((context) => Task.CompletedTask);
-
             return new AuthorizationMiddleware(requestDelegate, policyProvider);
         }