fixing P4vfsGetFileIdByFileName driver support

Author: jessk-msft

source/P4VFS.Core/Tests/TestDriver.cpp

@@ -218,14 +218,15 @@ typedef	struct _FILE_STANDARD_INFORMATION_EX {
 	BOOLEAN	MetadataAttribute;
 } FILE_STANDARD_INFORMATION_EX,	*PFILE_STANDARD_INFORMATION_EX;
 
+typedef struct _FILE_ID_INFORMATION {
+    ULONGLONG VolumeSerialNumber;
+    FILE_ID_128 FileId;
+} FILE_ID_INFORMATION, *PFILE_ID_INFORMATION;
+
 typedef enum _POOL_TYPE {
 	NonPagedPoolNx = 512,
 } POOL_TYPE;
 
-typedef struct _FILE_INTERNAL_INFORMATION {
-    LARGE_INTEGER IndexNumber;
-} FILE_INTERNAL_INFORMATION, *PFILE_INTERNAL_INFORMATION;
-
 #define	P4vfsTraceError(...)			__noop
 #define	P4vfsTraceWarning(...)			__noop
 #define	P4vfsTraceInfo(...)				__noop
@@ -262,10 +263,11 @@ typedef struct _FILE_INTERNAL_INFORMATION {
 #define	FileBasicInformation					4
 #define FileStandardInformation					5
 #define	FileInternalInformation					6
+#define FileIdInformation						59
 
 #define	FILE_OPEN								0x00000001
 #define	FILE_SYNCHRONOUS_IO_NONALERT			0x00000020
-#define FILE_NON_DIRECTORY_FILE                 0x00000040
+#define	FILE_NON_DIRECTORY_FILE					0x00000040
 #define	FILE_NO_INTERMEDIATE_BUFFERING			0x00000008
 #define	FILE_OPEN_REPARSE_POINT					0x00200000
 #define	FILE_OPEN_BY_FILE_ID					0x00002000
@@ -287,6 +289,8 @@ std::function<NTSTATUS(HANDLE)> FltClose;
 std::function<NTSTATUS(PFLT_INSTANCE, PFILE_OBJECT, PVOID, ULONG, FILE_INFORMATION_CLASS, PULONG)> FltQueryInformationFile;
 std::function<NTSTATUS(PFLT_INSTANCE, PFLT_VOLUME*)> FltGetVolumeFromInstance;
 std::function<NTSTATUS(PFLT_VOLUME, PUNICODE_STRING, PULONG)> FltGetVolumeName;
+std::function<NTSTATUS(PFLT_FILTER, PFILE_OBJECT, PFLT_VOLUME*)> FltGetVolumeFromFileObject;
+std::function<NTSTATUS(PFLT_FILTER, PFLT_VOLUME, PCUNICODE_STRING, PFLT_INSTANCE*)> FltGetVolumeInstanceFromName;
 
 std::function<PVOID(POOL_TYPE, SIZE_T, ULONG)> ExAllocatePoolZero;
 std::function<VOID(PVOID, ULONG)> ExFreePoolWithTag;
@@ -437,6 +441,9 @@ static void InternalTestDriverReset(const TestContext& context)
 	FltClose = P4VFS_DEFAULT_FUNCTION_NTSTATUS();
 	FltQueryInformationFile = P4VFS_DEFAULT_FUNCTION_NTSTATUS();
 	FltGetVolumeFromInstance = P4VFS_DEFAULT_FUNCTION_NTSTATUS();
+	FltGetVolumeName = P4VFS_DEFAULT_FUNCTION_NTSTATUS();
+	FltGetVolumeFromFileObject = P4VFS_DEFAULT_FUNCTION_NTSTATUS();
+	FltGetVolumeInstanceFromName = P4VFS_DEFAULT_FUNCTION_NTSTATUS();
 
 	ExAllocatePoolZero = [](POOL_TYPE, SIZE_T s, ULONG) -> PVOID { return GAlloc(s); };
 	ExFreePoolWithTag = [](PVOID p, ULONG) -> VOID { GFree(p); };

source/P4VFS.Driver/Include/DriverCore.h

@@ -117,7 +117,7 @@ NTSTATUS
 P4vfsGetFileIdByFileName(
 	_In_opt_ PFLT_INSTANCE pFltInstance,
 	_In_ PUNICODE_STRING pFileName,
-	__out PLONGLONG pFileId
+	_Out_ PUNICODE_STRING pOutFileIdPath
 	);
 
 NTSTATUS

source/P4VFS.Driver/Include/DriverVersion.h

@@ -5,7 +5,7 @@
 #define P4VFS_VER_MAJOR					1			// Increment this number almost never
 #define P4VFS_VER_MINOR					28			// Increment this number whenever the driver changes
 #define P4VFS_VER_BUILD					4			// Increment this number when a major user mode change has been made
-#define P4VFS_VER_REVISION				0			// Increment this number when we rebuild with any change
+#define P4VFS_VER_REVISION				3			// Increment this number when we rebuild with any change
 
 #define P4VFS_VER_STRINGIZE_EX(v)		L#v
 #define P4VFS_VER_STRINGIZE(v)			P4VFS_VER_STRINGIZE_EX(v)

source/P4VFS.Driver/Source/DriverCore.c

@@ -789,15 +789,18 @@ NTSTATUS
 P4vfsGetFileIdByFileName(
 	_In_opt_ PFLT_INSTANCE pFltInstance,
 	_In_ PUNICODE_STRING pFileName,
-	__out PLONGLONG pFileId
+	_Out_ PUNICODE_STRING pOutFileIdPath
 	)
 {
 	NTSTATUS status = STATUS_SUCCESS;
 	IO_STATUS_BLOCK	ioStatus = {0};
 	OBJECT_ATTRIBUTES objAttributes = {0};
 	HANDLE hLocalFile = NULL;
 	PFILE_OBJECT pLocalFileObject = NULL;
-	FILE_INTERNAL_INFORMATION internalInfo = {0};
+	FILE_ID_INFORMATION fileIdInfo = {0};
+	PFLT_VOLUME pVolume = NULL;
+	PFLT_INSTANCE pVolumeInstance = NULL;
+	UNICODE_STRING fileIdPath = {0};
 
 	PAGED_CODE();
 
@@ -808,47 +811,73 @@ P4vfsGetFileIdByFileName(
 		goto CLEANUP;
 	}
 
-	if (pFileId == NULL)
+	if (pOutFileIdPath == NULL)
 	{
 		status = STATUS_INVALID_PARAMETER;
-		P4vfsTraceError(Core, L"P4vfsGetFileIdByFileName: pFileId is NULL"); 
+		P4vfsTraceError(Core, L"P4vfsGetFileIdByFileName: pOutFileIdPath is NULL"); 
 		goto CLEANUP;
 	}
 
 	InitializeObjectAttributes(&objAttributes,
-							   pFileName,
-							   OBJ_KERNEL_HANDLE | OBJ_CASE_INSENSITIVE,
-							   NULL,
-							   NULL);
+								pFileName,
+								OBJ_KERNEL_HANDLE | OBJ_CASE_INSENSITIVE,
+								NULL,
+								NULL);
 
 	status = FltCreateFileEx2(g_FltContext.pFilter,
-							  pFltInstance,
-							  &hLocalFile,
-							  &pLocalFileObject,
-							  0,
-							  &objAttributes,
-							  &ioStatus,
-							  NULL,
-							  FILE_ATTRIBUTE_NORMAL,
-							  FILE_SHARE_VALID_FLAGS,
-							  FILE_OPEN,
-							  FILE_NON_DIRECTORY_FILE | FILE_OPEN_REPARSE_POINT,
-							  NULL,
-							  0,
-							  IO_IGNORE_SHARE_ACCESS_CHECK,
-							  NULL);
+								pFltInstance,
+								&hLocalFile,
+								&pLocalFileObject,
+								0,
+								&objAttributes,
+								&ioStatus,
+								NULL,
+								FILE_ATTRIBUTE_NORMAL,
+								FILE_SHARE_VALID_FLAGS,
+								FILE_OPEN,
+								FILE_NON_DIRECTORY_FILE | FILE_OPEN_REPARSE_POINT,
+								NULL,
+								0,
+								IO_IGNORE_SHARE_ACCESS_CHECK,
+								NULL);
 
 	if (!NT_SUCCESS(status))
 	{
 		P4vfsTraceError(Core, L"P4vfsGetFileIdByFileName: FltCreateFileEx2 failed [%wZ] [%!STATUS!]", pFileName, status); 
 		goto CLEANUP;
 	}
 
+	status = FltGetVolumeFromFileObject(g_FltContext.pFilter,
+										pLocalFileObject,
+										&pVolume);
+
+	if (!NT_SUCCESS(status))
+	{
+		P4vfsTraceError(Core, L"P4vfsGetFileIdByFileName: FltGetVolumeFromFileObject failed [%wZ] [%!STATUS!]", pFileName, status); 
+		goto CLEANUP;
+	}
+
+	if (pFltInstance == NULL)
+	{
+		status = FltGetVolumeInstanceFromName(g_FltContext.pFilter, 
+											  pVolume, 
+											  NULL, 
+											  &pVolumeInstance);
+
+		if (!NT_SUCCESS(status) || pVolumeInstance == NULL)
+		{
+			P4vfsTraceError(Core, L"P4vfsGetFileIdByFileName: FltGetVolumeInstanceFromName failed [%wZ] [%!STATUS!]", pFileName, status); 
+			goto CLEANUP;
+		}
+
+		pFltInstance = pVolumeInstance;
+	}
+
 	status = FltQueryInformationFile(pFltInstance,
 									 pLocalFileObject,
-									 &internalInfo,
-									 sizeof(internalInfo),
-									 FileInternalInformation,
+									 &fileIdInfo,
+									 sizeof(FILE_ID_INFORMATION),
+									 FileIdInformation,
 									 NULL);
 
 	if (!NT_SUCCESS(status))
@@ -857,7 +886,56 @@ P4vfsGetFileIdByFileName(
 		goto CLEANUP;
 	}
 
-	*pFileId = internalInfo.IndexNumber.QuadPart;
+	ULONG volumeNameLengthRequired = 0;
+	status = FltGetVolumeName(pVolume, NULL, &volumeNameLengthRequired);
+	if (!NT_SUCCESS(status) && (status != STATUS_BUFFER_TOO_SMALL))
+	{
+		P4vfsTraceError(Core, L"P4vfsGetFileIdByFileName: FltGetVolumeName length query failed [%wZ] [%!STATUS!]", pFileName, status); 
+		goto CLEANUP;
+	}
+
+	status = RtlUShortAdd((USHORT)volumeNameLengthRequired, sizeof(WCHAR)+sizeof(fileIdInfo.FileId), &fileIdPath.MaximumLength);
+	if (!NT_SUCCESS(status))
+	{
+		P4vfsTraceError(Core, L"P4vfsGetFileIdByFileName: RtlUShortAdd failed [%wZ] [%!STATUS!]", pFileName, status); 
+		goto CLEANUP;
+	}
+
+	status = P4vfsAllocateUnicodeString(P4VFS_FILE_NAME_ALLOC_TAG, &fileIdPath);
+	if (!NT_SUCCESS(status))
+	{
+		P4vfsTraceError(Core, L"P4vfsGetFileIdByFileName: P4vfsAllocateUnicodeString failed [%wZ] [%!STATUS!]", pFileName, status); 
+		goto CLEANUP;
+	}
+
+	status = FltGetVolumeName(pVolume, &fileIdPath, &volumeNameLengthRequired);
+	if (!NT_SUCCESS(status))
+	{
+		P4vfsTraceError(Core, L"P4vfsGetFileIdByFileName: FltGetVolumeName failed [%wZ] [%!STATUS!]", pFileName, status); 
+		goto CLEANUP;
+	}
+
+	status = RtlAppendUnicodeToString(&fileIdPath, L"\\");
+	if (!NT_SUCCESS(status))
+	{
+		P4vfsTraceError(Core, L"P4vfsGetFileIdByFileName: RtlAppendUnicodeToString separator failed [%wZ] fileIdPath [%wZ] [%!STATUS!]", pFileName, &fileIdPath, status); 
+		goto CLEANUP;
+	}
+
+	UNICODE_STRING fileIdString;
+	fileIdString.Length = sizeof(fileIdInfo.FileId);
+	fileIdString.MaximumLength = sizeof(fileIdInfo.FileId);
+	fileIdString.Buffer = (PWCHAR)&fileIdInfo.FileId;
+
+	status = RtlAppendUnicodeStringToString(&fileIdPath, &fileIdString);
+	if (!NT_SUCCESS(status))
+	{
+		P4vfsTraceError(Core, L"P4vfsGetFileIdByFileName: RtlAppendUnicodeToString fileIdString failed [%wZ] fileIdPath [%wZ] [%!STATUS!]", pFileName, &fileIdPath, status); 
+		goto CLEANUP;
+	}
+
+	*pOutFileIdPath = fileIdPath;
+	fileIdPath.Buffer = NULL;
 
 CLEANUP:
 	if (hLocalFile != NULL)
@@ -870,6 +948,21 @@ P4vfsGetFileIdByFileName(
 		ObDereferenceObject(pLocalFileObject);
 	}
 
+	if (pVolume != NULL)
+	{
+		FltObjectDereference(pVolume);
+	}
+
+    if (pVolumeInstance != NULL) 
+	{
+        FltObjectDereference(pVolumeInstance);
+    }
+
+	if (fileIdPath.Buffer != NULL)
+	{
+		ExFreePoolWithTag(fileIdPath.Buffer, P4VFS_FILE_NAME_ALLOC_TAG);
+	}
+
 	return status;
 }
 
@@ -889,80 +982,20 @@ P4vfsOpenReparsePoint(
 	IO_DRIVER_CREATE_CONTEXT createContext = {0};
 	HANDLE hLocalFile = NULL;
 	PFILE_OBJECT pLocalFileObject = NULL;
-	LONGLONG fileId = 0;
 	UNICODE_STRING fileIdPath = {0};
-	PFLT_VOLUME volume = NULL;
 
 	PAGED_CODE();
 
 	// We wish to open an existing reparse point file by using FILE_OPEN_BY_FILE_ID so as to avoid 
 	// directory notifications. Begin by finding the unique fileId by file path.
 
-	status = P4vfsGetFileIdByFileName(pFltInstance, pFileName, &fileId);
+	status = P4vfsGetFileIdByFileName(pFltInstance, pFileName, &fileIdPath);
 	if (!NT_SUCCESS(status))
 	{
 		P4vfsTraceError(Core, L"P4vfsOpenReparsePoint: P4vfsGetFileIdByFileName failed [%wZ] [%!STATUS!]", pFileName, status); 
 		goto CLEANUP;
 	}
 
-	// We will compose the fileIdPath with the current volume of this filter instance.
-
-	status = FltGetVolumeFromInstance(pFltInstance, &volume);
-	if (!NT_SUCCESS(status))
-	{
-		P4vfsTraceError(Core, L"P4vfsOpenReparsePoint: FltGetVolumeFromInstance failed [%wZ] [%!STATUS!]", pFileName, status); 
-		goto CLEANUP;
-	}
-
-	ULONG volumeNameLengthRequired = 0;
-	status = FltGetVolumeName(volume, NULL, &volumeNameLengthRequired);
-	if (!NT_SUCCESS(status) && (status != STATUS_BUFFER_TOO_SMALL))
-	{
-		P4vfsTraceError(Core, L"P4vfsOpenReparsePoint: FltGetVolumeName length query failed [%wZ] [%!STATUS!]", pFileName, status); 
-		goto CLEANUP;
-	}
-
-	RtlInitUnicodeString(&fileIdPath, NULL);
-	status = RtlUShortAdd((USHORT)volumeNameLengthRequired, sizeof(LONGLONG)+sizeof(WCHAR), &fileIdPath.MaximumLength);
-	if (!NT_SUCCESS(status))
-	{
-		P4vfsTraceError(Core, L"P4vfsOpenReparsePoint: RtlUShortAdd failed [%wZ] [%!STATUS!]", pFileName, status); 
-		goto CLEANUP;
-	}
-
-	status = P4vfsAllocateUnicodeString(P4VFS_FILE_NAME_ALLOC_TAG, &fileIdPath);
-	if (!NT_SUCCESS(status))
-	{
-		P4vfsTraceError(Core, L"P4vfsOpenReparsePoint: P4vfsAllocateUnicodeString failed [%wZ] [%!STATUS!]", pFileName, status); 
-		goto CLEANUP;
-	}
-
-	status = FltGetVolumeName(volume, &fileIdPath, &volumeNameLengthRequired);
-	if (!NT_SUCCESS(status))
-	{
-		P4vfsTraceError(Core, L"P4vfsOpenReparsePoint: FltGetVolumeName failed [%wZ] [%!STATUS!]", pFileName, status); 
-		goto CLEANUP;
-	}
-
-	status = RtlAppendUnicodeToString(&fileIdPath, L"\\");
-	if (!NT_SUCCESS(status))
-	{
-		P4vfsTraceError(Core, L"P4vfsOpenReparsePoint: RtlAppendUnicodeToString separator failed [%wZ] fileIdPath [%wZ] [%!STATUS!]", pFileName, &fileIdPath, status); 
-		goto CLEANUP;
-	}
-
-	UNICODE_STRING fileIdString;
-	fileIdString.Length = sizeof(fileId);
-	fileIdString.MaximumLength = sizeof(fileId);
-	fileIdString.Buffer = (PWCHAR)&fileId;
-
-	status = RtlAppendUnicodeStringToString(&fileIdPath, &fileIdString);
-	if (!NT_SUCCESS(status))
-	{
-		P4vfsTraceError(Core, L"P4vfsOpenReparsePoint: RtlAppendUnicodeToString fileIdString failed [%wZ] fileIdPath [%wZ] [%!STATUS!]", pFileName, &fileIdPath, status); 
-		goto CLEANUP;
-	}
-
 	IoInitializeDriverCreateContext(&createContext);
 #if (NTDDI_VERSION >= NTDDI_WIN10_RS1) && defined(P4VFS_KERNEL_MODE)
 	createContext.SiloContext =	PsGetHostSilo();
@@ -986,9 +1019,9 @@ P4vfsOpenReparsePoint(
 							  &ioStatus,
 							  NULL,
 							  FILE_ATTRIBUTE_NORMAL,
-							  FILE_SHARE_VALID_FLAGS,
+							  FILE_SHARE_READ |	FILE_SHARE_WRITE | FILE_SHARE_DELETE,
 							  FILE_OPEN,
-							  FILE_SYNCHRONOUS_IO_NONALERT | FILE_OPEN_REPARSE_POINT | FILE_NO_INTERMEDIATE_BUFFERING | FILE_OPEN_BY_FILE_ID,
+							  FILE_SYNCHRONOUS_IO_NONALERT | FILE_OPEN_REPARSE_POINT | FILE_OPEN_BY_FILE_ID,
 							  NULL,
 							  0,
 							  IO_IGNORE_SHARE_ACCESS_CHECK,
@@ -1018,11 +1051,6 @@ P4vfsOpenReparsePoint(
 		ObDereferenceObject(pLocalFileObject);
 	}
 
-	if (volume != NULL)
-	{
-		FltObjectDereference(volume);
-	}
-
 	if (fileIdPath.Buffer != NULL)
 	{
 		ExFreePoolWithTag(fileIdPath.Buffer, P4VFS_FILE_NAME_ALLOC_TAG);