fix #128: graceful failure on configuration errors

src/iisnode/cmoduleconfiguration.h

@@ -37,8 +37,7 @@ private:
 	static HRESULT GetConfigSection(IHttpContext* context, IAppHostElement** section, OLECHAR* configElement = L"system.webServer/iisnode");
 	static HRESULT GetString(IAppHostElement* section, LPCWSTR propertyName, LPWSTR* value);
 	static HRESULT GetBOOL(IAppHostElement* section, LPCWSTR propertyName, BOOL* value);
-	static HRESULT GetDWORD(IAppHostElement* section, LPCWSTR propertyName, DWORD* value);
-	static HRESULT GetConfig(IHttpContext* context, CModuleConfiguration** config);
+	static HRESULT GetDWORD(IAppHostElement* section, LPCWSTR propertyName, DWORD* value);	
 
 	CModuleConfiguration();
 	~CModuleConfiguration();
@@ -47,6 +46,8 @@ public:
 
 	static HRESULT Initialize(IHttpServer* server, HTTP_MODULE_ID moduleId);
 
+	static HRESULT GetConfig(IHttpContext* context, CModuleConfiguration** config);
+
 	static DWORD GetAsyncCompletionThreadCount(IHttpContext* ctx); 
 	static DWORD GetNodeProcessCountPerApplication(IHttpContext* ctx);
 	static LPCTSTR GetNodeProcessCommandLine(IHttpContext* ctx); 

src/iisnode/cnodeapplicationmanager.cpp

@@ -11,17 +11,25 @@ CNodeApplicationManager::CNodeApplicationManager(IHttpServer* server, HTTP_MODUL
 HRESULT CNodeApplicationManager::Initialize(IHttpContext* context)
 {
     HRESULT hr = S_OK;
+	CModuleConfiguration *config;
 
     if (!this->initialized)
     {
-        ENTER_SRW_EXCLUSIVE(this->srwlock)
+		if (S_OK != CModuleConfiguration::GetConfig(context, &config))
+		{
+			hr = IISNODE_ERROR_UNABLE_TO_READ_CONFIGURATION;
+		}
+		else
+		{
+			ENTER_SRW_EXCLUSIVE(this->srwlock)
 
-        if (!this->initialized)
-        {
-            hr = this->InitializeCore(context);
-        }
+			if (!this->initialized)
+			{
+				hr = this->InitializeCore(context);
+			}
 
-        LEAVE_SRW_EXCLUSIVE(this->srwlock)
+			LEAVE_SRW_EXCLUSIVE(this->srwlock)
+		}
     }
 
     return hr;

src/iisnode/cprotocolbridge.cpp

@@ -10,8 +10,64 @@ HRESULT CProtocolBridge::PostponeProcessing(CNodeHttpStoredContext* context, DWO
 	return async->SetTimer(context->GetAsyncContext(), &delay);
 }
 
+#define LOCAL127            0x0100007F  // 127.0.0.1
+
+BOOL CProtocolBridge::IsLocalCall(IHttpContext* ctx)
+{
+	PSOCKADDR src = ctx->GetRequest()->GetRemoteAddress();
+	PSOCKADDR dest = ctx->GetRequest()->GetLocalAddress();
+
+	if (AF_INET == src->sa_family && AF_INET == dest->sa_family)
+	{
+        DWORD srcAddress = ntohl(((PSOCKADDR_IN)src)->sin_addr.s_addr);
+		DWORD destAddress = ntohl(((PSOCKADDR_IN)dest)->sin_addr.s_addr);
+
+		return srcAddress == destAddress || LOCAL127 == srcAddress || LOCAL127 == destAddress;
+	}
+	else if (AF_INET6 == src->sa_family && AF_INET6 == dest->sa_family)
+	{
+        IN6_ADDR* srcAddress = &((PSOCKADDR_IN6)src)->sin6_addr;
+		IN6_ADDR* destAddress = &((PSOCKADDR_IN6)dest)->sin6_addr;
+
+		if (0 == memcmp(srcAddress, destAddress, sizeof IN6_ADDR))
+		{
+			return TRUE;
+		}
+
+		if (IN6_IS_ADDR_LOOPBACK(srcAddress) || IN6_IS_ADDR_LOOPBACK(destAddress))
+		{
+			return TRUE;
+		}
+	}
+
+	return FALSE;
+}
+
 BOOL CProtocolBridge::SendIisnodeError(IHttpContext* httpCtx, HRESULT hr)
 {
+	if (IISNODE_ERROR_UNABLE_TO_READ_CONFIGURATION == hr)
+	{
+		if (CProtocolBridge::IsLocalCall(httpCtx))
+		{
+			CProtocolBridge::SendSyncResponse(
+				httpCtx, 
+				200, 
+				"OK", 
+				hr, 
+				TRUE, 
+				"iisnode was unable to read the configuration file. Make sure the web.config file syntax is correct. In particular, verify the "
+				" <a href=""https://github.com/tjanczuk/iisnode/blob/master/src/samples/configuration/web.config"">"
+				"iisnode configuration section</a> matches the expected schema. The schema of the iisnode section that your version of iisnode requiries is stored in the "
+				"%systemroot%\\system32\\inetsrv\\config\\schema\\iisnode_schema.xml file.");
+
+			return TRUE;
+		}
+		else
+		{
+			return FALSE;
+		}
+	}
+
 	if (!CModuleConfiguration::GetDevErrorsEnabled(httpCtx))
 	{
 		return FALSE;

src/iisnode/cprotocolbridge.h

@@ -12,6 +12,7 @@ private:
 	static HRESULT PostponeProcessing(CNodeHttpStoredContext* context, DWORD dueTime);	
 	static HRESULT EnsureBuffer(CNodeHttpStoredContext* context);
 	static HRESULT FinalizeResponseCore(CNodeHttpStoredContext * context, REQUEST_NOTIFICATION_STATUS status, HRESULT error, CNodeEventProvider* log, PCWSTR etw, UCHAR level);
+	static BOOL IsLocalCall(IHttpContext* ctx);
 
 	// processing stages
 	static void WINAPI ChildContextCompleted(DWORD error, DWORD bytesTransfered, LPOVERLAPPED overlapped);

src/iisnode/errors.h

@@ -8,5 +8,6 @@
 #define IISNODE_ERROR_UNABLE_TO_START_NODE_EXE 1028L
 #define IISNODE_ERROR_UNABLE_TO_CREATE_LOG_FILE 1029L
 #define IISNODE_ERROR_UNABLE_TO_CREATE_DEBUGGER_FILES 1030L
+#define IISNODE_ERROR_UNABLE_TO_READ_CONFIGURATION 1031L
 
 #endif

src/iisnode/iisnode.vcxproj

@@ -249,6 +249,7 @@ copy /y $(ProjectDir)\..\config\* $(ProjectDir)\..\..\build\$(Configuration)\$(P
     <None Include="..\..\test\functional\tests\112_dev_errors.js" />
     <None Include="..\..\test\functional\tests\113_encoding.js" />
     <None Include="..\..\test\functional\tests\115_customheaders.js" />
+    <None Include="..\..\test\functional\tests\116_configerror.js" />
     <None Include="..\..\test\functional\tests\200_samples.bat" />
     <None Include="..\..\test\functional\tests\node_modules\iisnodeassert.js" />
     <None Include="..\..\test\functional\tests\parts\106_autoupdate_first.js" />
@@ -288,6 +289,8 @@ copy /y $(ProjectDir)\..\config\* $(ProjectDir)\..\..\build\$(Configuration)\$(P
     <None Include="..\..\test\functional\www\113_encoding\web.config" />
     <None Include="..\..\test\functional\www\115_customheaders\hello.js" />
     <None Include="..\..\test\functional\www\115_customheaders\web.config" />
+    <None Include="..\..\test\functional\www\116_configerror\hello.js" />
+    <None Include="..\..\test\functional\www\116_configerror\web.config" />
     <None Include="..\..\test\performance\client.bat" />
     <None Include="..\..\test\performance\localRun.bat" />
     <None Include="..\..\test\performance\readme.txt" />

src/iisnode/iisnode.vcxproj.filters

@@ -114,6 +114,9 @@
     <Filter Include="Tests\functional\www\115_customheaders">
       <UniqueIdentifier>{994959e7-12c0-43f7-a10b-24899813a857}</UniqueIdentifier>
     </Filter>
+    <Filter Include="Tests\functional\www\116_configerror">
+      <UniqueIdentifier>{500f40cf-c2f5-4264-b061-b4f1e59f50f5}</UniqueIdentifier>
+    </Filter>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="main.cpp">
@@ -492,6 +495,15 @@
     <None Include="..\..\test\functional\www\115_customheaders\web.config">
       <Filter>Tests\functional\www\115_customheaders</Filter>
     </None>
+    <None Include="..\..\test\functional\tests\116_configerror.js">
+      <Filter>Tests\functional\tests</Filter>
+    </None>
+    <None Include="..\..\test\functional\www\116_configerror\hello.js">
+      <Filter>Tests\functional\www\116_configerror</Filter>
+    </None>
+    <None Include="..\..\test\functional\www\116_configerror\web.config">
+      <Filter>Tests\functional\www\116_configerror</Filter>
+    </None>
   </ItemGroup>
   <ItemGroup>
     <ResourceCompile Include="iisnode.rc" />

test/functional/tests/116_configerror.js

@@ -0,0 +1,9 @@
+/*
+Local request to iisnode with a configuration syntax error returns a friendly 200 response
+*/
+
+var iisnodeassert = require("iisnodeassert");
+
+iisnodeassert.sequence([
+    iisnodeassert.get(10000, "/116_configerror/hello.js", 200)
+]);

test/functional/www/116_configerror/hello.js

@@ -0,0 +1,6 @@
+var http = require('http');
+
+http.createServer(function (req, res) {
+    res.writeHead(200, {'Content-Type': 'text/html'});
+    res.end('Hello, world!');
+}).listen(process.env.PORT);  

test/functional/www/116_configerror/web.config

@@ -0,0 +1,10 @@
+<configuration>
+  <system.webServer>
+    <handlers>
+      <add name="iisnode" path="hello.js" verb="*" modules="iisnode" />
+    </handlers>
+
+    <iisnode idontexist="12" />
+
+  </system.webServer>
+</configuration>