Set connection close with a switch for ANCM out of process (#16643)

src/Servers/IIS/AspNetCoreModuleV2/CommonLib/config_utility.h

@@ -14,6 +14,7 @@ class ConfigUtility
     #define CS_ASPNETCORE_HANDLER_SETTINGS                   L"handlerSettings"
     #define CS_ASPNETCORE_HANDLER_VERSION                    L"handlerVersion"
     #define CS_ASPNETCORE_DEBUG_FILE                         L"debugFile"
+    #define CS_ASPNETCORE_FORWARD_RESPONSE_CONNECTION_HEADER L"forwardResponseConnectionHeader"
     #define CS_ASPNETCORE_DEBUG_LEVEL                        L"debugLevel"
     #define CS_ASPNETCORE_HANDLER_SETTINGS_NAME              L"name"
     #define CS_ASPNETCORE_HANDLER_SETTINGS_VALUE             L"value"
@@ -40,6 +41,13 @@ public:
         return FindKeyValuePair(pElement, CS_ASPNETCORE_DEBUG_LEVEL, strDebugFile);
     }
 
+    static
+    HRESULT
+    FindForwardResponseConnectionHeader(IAppHostElement* pElement, STRU& strForwardResponseConnectionHeader)
+    {
+        return FindKeyValuePair(pElement, CS_ASPNETCORE_FORWARD_RESPONSE_CONNECTION_HEADER, strForwardResponseConnectionHeader);
+    }
+
 private:
     static
     HRESULT

src/Servers/IIS/AspNetCoreModuleV2/OutOfProcessRequestHandler/forwardinghandler.cpp

@@ -55,6 +55,7 @@ FORWARDING_HANDLER::FORWARDING_HANDLER(
     LOG_TRACE(L"FORWARDING_HANDLER::FORWARDING_HANDLER");
 
     m_fWebSocketSupported = m_pApplication->QueryWebsocketStatus();
+    m_fForwardResponseConnectionHeader = m_pApplication->QueryConfig()->QueryForwardResponseConnectionHeader()->Equals(L"true", /* ignoreCase */ 1);
     InitializeSRWLock(&m_RequestLock);
 }
 
@@ -2212,10 +2213,14 @@ FORWARDING_HANDLER::SetStatusAndHeaders(
                     break;
                 }
                 __fallthrough;
-            case HttpHeaderConnection:
             case HttpHeaderDate:
                 continue;
-
+            case HttpHeaderConnection:
+                if (!m_fForwardResponseConnectionHeader)
+                {
+                    continue;
+                }
+                break;
             case HttpHeaderServer:
                 fServerHeaderPresent = TRUE;
                 break;

src/Servers/IIS/AspNetCoreModuleV2/OutOfProcessRequestHandler/forwardinghandler.h

@@ -179,6 +179,7 @@ private:
     HINTERNET                           m_hRequest;
     FORWARDING_REQUEST_STATUS           m_RequestStatus;
 
+    BOOL                                m_fForwardResponseConnectionHeader;
     BOOL                                m_fWebSocketEnabled;
     BOOL                                m_fWebSocketSupported;
     BOOL                                m_fResponseHeadersReceivedAndSet;

src/Servers/IIS/AspNetCoreModuleV2/RequestHandlerLib/requesthandler_config.cpp

@@ -379,6 +379,12 @@ REQUESTHANDLER_CONFIG::Populate(
         goto Finished;
     }
 
+    hr = ConfigUtility::FindForwardResponseConnectionHeader(pAspNetCoreElement, m_struForwardResponseConnectionHeader);
+    if (FAILED(hr))
+    {
+        goto Finished;
+    }
+
 Finished:
 
     if (pAspNetCoreElement != NULL)

src/Servers/IIS/AspNetCoreModuleV2/RequestHandlerLib/requesthandler_config.h

@@ -218,6 +218,12 @@ public:
         return &m_struConfigPath;
     }
 
+    STRU*
+    QueryForwardResponseConnectionHeader()
+    {
+        return &m_struForwardResponseConnectionHeader;
+    }
+
 protected:
 
     //
@@ -249,6 +255,7 @@ protected:
     STRU                   m_struApplicationPhysicalPath;
     STRU                   m_struApplicationVirtualPath;
     STRU                   m_struConfigPath;
+    STRU                   m_struForwardResponseConnectionHeader;
     BOOL                   m_fStdoutLogEnabled;
     BOOL                   m_fForwardWindowsAuthToken;
     BOOL                   m_fDisableStartUpErrorPage;

src/Servers/IIS/IIS/test/Common.FunctionalTests/HttpsTests.cs

@@ -162,6 +162,35 @@ namespace Microsoft.AspNetCore.Server.IIS.FunctionalTests
             Assert.Equal("NOVALUE", await client.GetStringAsync("/HTTPS_PORT"));
         }
 
+        [ConditionalFact]
+        [RequiresNewHandler]
+        [RequiresNewShim]
+        public async Task SetsConnectionCloseHeader()
+        {
+            // Only tests OutOfProcess as the Connection header is removed for out of process and not inprocess. 
+            // This test checks a quirk to allow setting the Connection header.
+            var deploymentParameters = Fixture.GetBaseDeploymentParameters(HostingModel.OutOfProcess);
+
+            deploymentParameters.HandlerSettings["forwardResponseConnectionHeader"] = "true";
+            var deploymentResult = await DeployAsync(deploymentParameters);
+
+            var response = await deploymentResult.HttpClient.GetAsync("ConnectionClose");
+            Assert.Equal(true, response.Headers.ConnectionClose);
+        }
+
+        [ConditionalFact]
+        [RequiresNewHandler]
+        [RequiresNewShim]
+        public async Task ConnectionCloseIsNotPropagated()
+        {
+            var deploymentParameters = Fixture.GetBaseDeploymentParameters(HostingModel.OutOfProcess);
+
+            var deploymentResult = await DeployAsync(deploymentParameters);
+
+            var response = await deploymentResult.HttpClient.GetAsync("ConnectionClose");
+            Assert.Null(response.Headers.ConnectionClose);
+        }
+
         private static HttpClient CreateNonValidatingClient(IISDeploymentResult deploymentResult)
         {
             var handler = new HttpClientHandler

src/Servers/IIS/IIS/test/testassets/InProcessWebSite/Startup.cs

@@ -144,6 +144,12 @@ namespace TestSite
             return Task.CompletedTask;
         }
 
+        public Task ConnectionClose(HttpContext context)
+        {
+            context.Response.Headers["connection"] = "close";
+            return Task.CompletedTask;
+        }
+
         public Task OverrideServer(HttpContext context)
         {
             context.Response.Headers["Server"] = "MyServer/7.8";