From 82f84f5bf70cf25e0eb15b9e88ffd79297615fac Mon Sep 17 00:00:00 2001
From: Bill Zissimopoulos <billziss@navimatics.com>
Date: Thu, 23 Feb 2023 12:31:01 +0000
Subject: [PATCH] sys: FspFsvolQueryInformation: FileIdInformation

---
 src/sys/fileinfo.c           | 33 +++++++++++++++++++++++++++++++++
 tst/winfsp-tests/info-test.c | 22 ++++++++++++++++++++++
 2 files changed, 55 insertions(+)

diff --git a/src/sys/fileinfo.c b/src/sys/fileinfo.c
index c0e69b57..2cbaf119 100644
--- a/src/sys/fileinfo.c
+++ b/src/sys/fileinfo.c
@@ -33,6 +33,8 @@ static NTSTATUS FspFsvolQueryBasicInformation(PFILE_OBJECT FileObject,
 static NTSTATUS FspFsvolQueryEaInformation(PFILE_OBJECT FileObject,
     PVOID *PBuffer, PVOID BufferEnd,
     const FSP_FSCTL_FILE_INFO *FileInfo);
+static NTSTATUS FspFsvolQueryIdInformation(PFILE_OBJECT FileObject,
+    PVOID *PBuffer, PVOID BufferEnd);
 static NTSTATUS FspFsvolQueryInternalInformation(PFILE_OBJECT FileObject,
     PVOID *PBuffer, PVOID BufferEnd);
 static NTSTATUS FspFsvolQueryNameInformation(PFILE_OBJECT FileObject,
@@ -106,6 +108,7 @@ FAST_IO_QUERY_OPEN FspFastIoQueryOpen;
 #pragma alloc_text(PAGE, FspFsvolQueryAttributeTagInformation)
 #pragma alloc_text(PAGE, FspFsvolQueryBasicInformation)
 #pragma alloc_text(PAGE, FspFsvolQueryEaInformation)
+#pragma alloc_text(PAGE, FspFsvolQueryIdInformation)
 #pragma alloc_text(PAGE, FspFsvolQueryInternalInformation)
 #pragma alloc_text(PAGE, FspFsvolQueryNameInformation)
 #pragma alloc_text(PAGE, FspFsvolQueryNetworkOpenInformation)
@@ -288,6 +291,32 @@ static NTSTATUS FspFsvolQueryEaInformation(PFILE_OBJECT FileObject,
     return STATUS_SUCCESS;
 }
 
+static NTSTATUS FspFsvolQueryIdInformation(PFILE_OBJECT FileObject,
+    PVOID *PBuffer, PVOID BufferEnd)
+{
+    PAGED_CODE();
+
+    PFILE_ID_INFORMATION Info = (PFILE_ID_INFORMATION)*PBuffer;
+    FSP_FILE_NODE *FileNode = FileObject->FsContext;
+    PDEVICE_OBJECT FsvolDeviceObject = FileNode->FsvolDeviceObject;
+    FSP_FSVOL_DEVICE_EXTENSION *FsvolDeviceExtension = FspFsvolDeviceExtension(FsvolDeviceObject);
+    union
+    {
+        UINT64 IndexNumber;
+        FILE_ID_128 FileId;
+    } FileIdBuf = { .IndexNumber = FileNode->IndexNumber };
+
+    if ((PVOID)(Info + 1) > BufferEnd)
+        return STATUS_BUFFER_TOO_SMALL;
+
+    Info->VolumeSerialNumber = FsvolDeviceExtension->VolumeParams.VolumeSerialNumber;
+    Info->FileId = FileIdBuf.FileId;
+
+    *PBuffer = (PVOID)(Info + 1);
+
+    return STATUS_SUCCESS;
+}
+
 static NTSTATUS FspFsvolQueryInternalInformation(PFILE_OBJECT FileObject,
     PVOID *PBuffer, PVOID BufferEnd)
 {
@@ -961,6 +990,10 @@ static NTSTATUS FspFsvolQueryInformation(
     case FileHardLinkInformation:
         Result = STATUS_NOT_SUPPORTED;  /* no hard link support */
         return Result;
+    case FileIdInformation:
+        Result = FspFsvolQueryIdInformation(FileObject, &Buffer, BufferEnd);
+        Irp->IoStatus.Information = (UINT_PTR)((PUINT8)Buffer - (PUINT8)Irp->AssociatedIrp.SystemBuffer);
+        return Result;
     case FileInternalInformation:
         Result = FspFsvolQueryInternalInformation(FileObject, &Buffer, BufferEnd);
         Irp->IoStatus.Information = (UINT_PTR)((PUINT8)Buffer - (PUINT8)Irp->AssociatedIrp.SystemBuffer);
diff --git a/tst/winfsp-tests/info-test.c b/tst/winfsp-tests/info-test.c
index 3e91d0e6..caedbe43 100644
--- a/tst/winfsp-tests/info-test.c
+++ b/tst/winfsp-tests/info-test.c
@@ -273,6 +273,28 @@ void getfileinfo_dotest(ULONG Flags, PWSTR Prefix, ULONG FileInfoTimeout)
     ASSERT(0 == FileInfo.nFileSizeLow && 0 == FileInfo.nFileSizeHigh);
     ASSERT(1 == FileInfo.nNumberOfLinks);
 
+    if (-1 != Flags)
+    {
+        /* WinFsp file systems respond to FileIdInformation queries with the IndexNumber zero-extended */
+        struct
+        {
+            /* FILE_ID_INFO is missing from old version of SDK that we are still using */
+            ULONGLONG VolumeSerialNumber;
+            UINT8 FileId[16];
+        } IdInfo;
+        union
+        {
+            UINT64 IndexNumber;
+            UINT8 FileId[16];
+        } ExpectedFileId = { 0 };
+        Success = GetFileInformationByHandleEx(Handle, 0x12/*FileIdInfo*/, &IdInfo, sizeof IdInfo);
+        if (Success)
+        {
+            ExpectedFileId.IndexNumber = ((UINT64)FileInfo.nFileIndexHigh << 32) | (UINT64)FileInfo.nFileIndexLow;
+            ASSERT(0 == memcmp(&ExpectedFileId.FileId, &IdInfo.FileId, sizeof IdInfo.FileId));
+        }
+    }
+
     CloseHandle(Handle);
 
     memfs_stop(memfs);