dll: special case STATUS_OBJECT_NAME_NOT_FOUND and STATUS_OBJECT_NAME_COLLISION to handle open/create via symlink

tst: memfs: support reparse point functionality over a named stream and fix status return on create collision over directory

ext/test

@@ -1 +1 @@
-Subproject commit 0059e0a24a5ddb612e112dedfa5aaf81d6b522e3
+Subproject commit 2d629a427ff1d0f04d2117a414cd7b385ae8b95f

src/dll/fsop.c

@@ -602,9 +602,84 @@ static NTSTATUS FspFileSystemOpCreate_FileOpenTargetDirectory(FSP_FILE_SYSTEM *F
     return STATUS_SUCCESS;
 }
 
+static NTSTATUS FspFileSystemOpCreate_NotFoundCheck(FSP_FILE_SYSTEM *FileSystem,
+    FSP_FSCTL_TRANSACT_REQ *Request, FSP_FSCTL_TRANSACT_RSP *Response)
+{
+    /*
+     * This handles an Open of a named stream done via a symlink. The file system
+     * has returned STATUS_OBJECT_NAME_NOT_FOUND, but we check to see if the main
+     * file is a reparse point that can be resolved.
+     */
+
+    NTSTATUS Result;
+    UINT32 FileAttributes;
+
+    if (0 == FileSystem->Interface->GetSecurityByName ||
+        0 == FileSystem->Interface->ResolveReparsePoints)
+        return STATUS_OBJECT_NAME_NOT_FOUND;
+
+    if (!Request->Req.Create.NamedStream ||
+        (Request->Req.Create.CreateOptions & FILE_OPEN_REPARSE_POINT))
+        return STATUS_OBJECT_NAME_NOT_FOUND;
+
+    ((PWSTR)Request->Buffer)[Request->Req.Create.NamedStream / sizeof(WCHAR)] = L'\0';
+    Result = FileSystem->Interface->GetSecurityByName(
+        FileSystem, (PWSTR)Request->Buffer, &FileAttributes, 0, 0);
+    ((PWSTR)Request->Buffer)[Request->Req.Create.NamedStream / sizeof(WCHAR)] = L':';
+
+    if (STATUS_SUCCESS != Result ||
+        FILE_ATTRIBUTE_REPARSE_POINT != (FileAttributes & FILE_ATTRIBUTE_REPARSE_POINT))
+        return STATUS_OBJECT_NAME_NOT_FOUND;
+
+    FileAttributes = FspPathSuffixIndex((PWSTR)Request->Buffer);
+    Result = FspFileSystemCallResolveReparsePoints(
+        FileSystem, Request, Response, FileAttributes);
+    if (STATUS_REPARSE != Result)
+        return STATUS_OBJECT_NAME_NOT_FOUND;
+
+    return STATUS_REPARSE;
+}
+
+static NTSTATUS FspFileSystemOpCreate_CollisionCheck(FSP_FILE_SYSTEM *FileSystem,
+    FSP_FSCTL_TRANSACT_REQ *Request, FSP_FSCTL_TRANSACT_RSP *Response)
+{
+    /*
+     * This handles a Create done via a symlink. The file system has returned
+     * STATUS_OBJECT_NAME_COLLISION, but we check to see if the collision is
+     * due to a reparse point that can be resolved.
+     */
+
+    NTSTATUS Result;
+    UINT32 FileAttributes;
+
+    if (0 == FileSystem->Interface->GetSecurityByName ||
+        0 == FileSystem->Interface->ResolveReparsePoints)
+        return STATUS_OBJECT_NAME_COLLISION;
+
+    if (Request->Req.Create.CreateOptions & FILE_OPEN_REPARSE_POINT)
+        return STATUS_OBJECT_NAME_COLLISION;
+
+    Result = FileSystem->Interface->GetSecurityByName(
+        FileSystem, (PWSTR)Request->Buffer, &FileAttributes, 0, 0);
+    if (STATUS_SUCCESS != Result ||
+        FILE_ATTRIBUTE_REPARSE_POINT !=
+            (FileAttributes & (FILE_ATTRIBUTE_DIRECTORY | FILE_ATTRIBUTE_REPARSE_POINT)))
+        return STATUS_OBJECT_NAME_COLLISION;
+
+    FileAttributes = FspPathSuffixIndex((PWSTR)Request->Buffer);
+    Result = FspFileSystemCallResolveReparsePoints(
+        FileSystem, Request, Response, FileAttributes);
+    if (STATUS_REPARSE != Result)
+        return STATUS_OBJECT_NAME_COLLISION;
+
+    return STATUS_REPARSE;
+}
+
 FSP_API NTSTATUS FspFileSystemOpCreate(FSP_FILE_SYSTEM *FileSystem,
     FSP_FSCTL_TRANSACT_REQ *Request, FSP_FSCTL_TRANSACT_RSP *Response)
 {
+    NTSTATUS Result;
+
     if (0 == FileSystem->Interface->Create ||
         0 == FileSystem->Interface->Open ||
         0 == FileSystem->Interface->Overwrite)
@@ -616,19 +691,32 @@ FSP_API NTSTATUS FspFileSystemOpCreate(FSP_FILE_SYSTEM *FileSystem,
     switch ((Request->Req.Create.CreateOptions >> 24) & 0xff)
     {
     case FILE_CREATE:
-        return FspFileSystemOpCreate_FileCreate(FileSystem, Request, Response);
+        Result = FspFileSystemOpCreate_FileCreate(FileSystem, Request, Response);
+        break;
     case FILE_OPEN:
-        return FspFileSystemOpCreate_FileOpen(FileSystem, Request, Response);
+        Result = FspFileSystemOpCreate_FileOpen(FileSystem, Request, Response);
+        break;
     case FILE_OPEN_IF:
-        return FspFileSystemOpCreate_FileOpenIf(FileSystem, Request, Response);
+        Result = FspFileSystemOpCreate_FileOpenIf(FileSystem, Request, Response);
+        break;
     case FILE_OVERWRITE:
     case FILE_SUPERSEDE:
-        return FspFileSystemOpCreate_FileOverwrite(FileSystem, Request, Response);
+        Result = FspFileSystemOpCreate_FileOverwrite(FileSystem, Request, Response);
+        break;
     case FILE_OVERWRITE_IF:
-        return FspFileSystemOpCreate_FileOverwriteIf(FileSystem, Request, Response);
+        Result = FspFileSystemOpCreate_FileOverwriteIf(FileSystem, Request, Response);
+        break;
     default:
-        return STATUS_INVALID_PARAMETER;
+        Result = STATUS_INVALID_PARAMETER;
+        break;
     }
+
+    if (STATUS_OBJECT_NAME_NOT_FOUND == Result)
+        Result = FspFileSystemOpCreate_NotFoundCheck(FileSystem, Request, Response);
+    else if (STATUS_OBJECT_NAME_COLLISION == Result)
+        Result = FspFileSystemOpCreate_CollisionCheck(FileSystem, Request, Response);
+
+    return Result;
 }
 
 FSP_API NTSTATUS FspFileSystemOpOverwrite(FSP_FILE_SYSTEM *FileSystem,
@@ -1093,7 +1181,7 @@ FSP_API BOOLEAN FspFileSystemFindReparsePoint(FSP_FILE_SYSTEM *FileSystem,
         LastPathComponent = RemainderPath;
         while (L'\\' != *RemainderPath)
         {
-            if (L'\0' == *RemainderPath)
+            if (L'\0' == *RemainderPath || L':' == *RemainderPath)
                 return FALSE;
             RemainderPath++;
         }
@@ -1161,7 +1249,7 @@ FSP_API NTSTATUS FspFileSystemResolveReparsePointsInternal(FSP_FILE_SYSTEM *File
         LastPathComponent = RemainderPath;
         while (L'\\' != *RemainderPath)
         {
-            if (L'\0' == *RemainderPath)
+            if (L'\0' == *RemainderPath || L':' == *RemainderPath)
             {
                 if (!ResolveLastPathComponent)
                     goto symlink_exit;
@@ -1217,16 +1305,18 @@ FSP_API NTSTATUS FspFileSystemResolveReparsePointsInternal(FSP_FILE_SYSTEM *File
 
         RemainderChar = *RemainderPath; *RemainderPath = L'\0';
         ReparseDataSize = ReparseDataSize0;
-        Result = GetReparsePointByName(FileSystem, Context, TargetPath, '\0' != RemainderChar,
+        Result = GetReparsePointByName(FileSystem, Context, TargetPath, L'\\' == RemainderChar,
             ReparseData, &ReparseDataSize);
         *RemainderPath = RemainderChar;
 
         if (STATUS_NOT_A_REPARSE_POINT == Result)
             /* it was not a reparse point; continue */
             continue;
+        else if (STATUS_OBJECT_NAME_NOT_FOUND == Result && L'\\' != RemainderChar)
+            goto symlink_exit;
         else if (!NT_SUCCESS(Result))
         {
-            if (STATUS_OBJECT_NAME_NOT_FOUND != Result || '\0' != RemainderChar)
+            if (STATUS_OBJECT_NAME_NOT_FOUND != Result)
                 Result = STATUS_OBJECT_PATH_NOT_FOUND;
             return Result;
         }

src/dll/library.h

@@ -53,4 +53,17 @@ PWSTR FspDiagIdent(VOID);
 
 BOOL WINAPI FspServiceConsoleCtrlHandler(DWORD CtrlType);
 
+static inline ULONG FspPathSuffixIndex(PWSTR FileName)
+{
+    WCHAR Root[2] = L"\\";
+    PWSTR Remain, Suffix;
+    ULONG Result;
+
+    FspPathSuffix(FileName, &Remain, &Suffix, Root);
+    Result = Remain == Root ? 0 : (ULONG)(Suffix - Remain);
+    FspPathCombine(FileName, Suffix);
+
+    return Result;
+}
+
 #endif

src/dll/security.c

@@ -48,19 +48,6 @@ static NTSTATUS FspGetSecurityByName(FSP_FILE_SYSTEM *FileSystem,
     }
 }
 
-static inline ULONG FspPathSuffixIndex(PWSTR FileName)
-{
-    WCHAR Root[2] = L"\\";
-    PWSTR Remain, Suffix;
-    ULONG Result;
-
-    FspPathSuffix(FileName, &Remain, &Suffix, Root);
-    Result = Remain == Root ? 0 : (ULONG)(Suffix - Remain);
-    FspPathCombine(FileName, Suffix);
-
-    return Result;
-}
-
 FSP_API NTSTATUS FspAccessCheckEx(FSP_FILE_SYSTEM *FileSystem,
     FSP_FSCTL_TRANSACT_REQ *Request,
     BOOLEAN CheckParentOrMain, BOOLEAN AllowTraverseCheck,

tst/memfs/memfs.cpp

@@ -470,7 +470,13 @@ static NTSTATUS Create(FSP_FILE_SYSTEM *FileSystem,
 
     FileNode = MemfsFileNodeMapGet(Memfs->FileNodeMap, FileName);
     if (0 != FileNode)
-        return STATUS_OBJECT_NAME_COLLISION;
+    {
+        if ((CreateOptions & FILE_NON_DIRECTORY_FILE) &&
+            0 != (FileNode->FileInfo.FileAttributes & FILE_ATTRIBUTE_DIRECTORY))
+            return STATUS_FILE_IS_A_DIRECTORY;
+        else
+            return STATUS_OBJECT_NAME_COLLISION;
+    }
 
     if (!MemfsFileNodeMapGetParent(Memfs->FileNodeMap, FileName, &Result))
         return Result;
@@ -1107,6 +1113,11 @@ static NTSTATUS GetReparsePointByName(
     MEMFS *Memfs = (MEMFS *)FileSystem->UserContext;
     MEMFS_FILE_NODE *FileNode;
 
+#if defined(MEMFS_NAMED_STREAMS)
+    /* GetReparsePointByName will never receive a named stream */
+    assert(0 == wcschr(FileName, L':'));
+#endif
+
     FileNode = MemfsFileNodeMapGet(Memfs->FileNodeMap, FileName);
     if (0 == FileNode)
         return STATUS_OBJECT_NAME_NOT_FOUND;
@@ -1133,6 +1144,11 @@ static NTSTATUS GetReparsePoint(FSP_FILE_SYSTEM *FileSystem,
 {
     MEMFS_FILE_NODE *FileNode = (MEMFS_FILE_NODE *)FileNode0;
 
+#if defined(MEMFS_NAMED_STREAMS)
+    if (0 != FileNode->MainFileNode)
+        FileNode = FileNode->MainFileNode;
+#endif
+
     if (0 == (FileNode->FileInfo.FileAttributes & FILE_ATTRIBUTE_REPARSE_POINT))
         return STATUS_NOT_A_REPARSE_POINT;
 
@@ -1155,6 +1171,11 @@ static NTSTATUS SetReparsePoint(FSP_FILE_SYSTEM *FileSystem,
     PVOID ReparseData;
     NTSTATUS Result;
 
+#if defined(MEMFS_NAMED_STREAMS)
+    if (0 != FileNode->MainFileNode)
+        FileNode = FileNode->MainFileNode;
+#endif
+
     if (MemfsFileNodeMapHasChild(Memfs->FileNodeMap, FileNode))
         return STATUS_DIRECTORY_NOT_EMPTY;
 
@@ -1189,6 +1210,11 @@ static NTSTATUS DeleteReparsePoint(FSP_FILE_SYSTEM *FileSystem,
     MEMFS_FILE_NODE *FileNode = (MEMFS_FILE_NODE *)FileNode0;
     NTSTATUS Result;
 
+#if defined(MEMFS_NAMED_STREAMS)
+    if (0 != FileNode->MainFileNode)
+        FileNode = FileNode->MainFileNode;
+#endif
+
     if (0 != FileNode->ReparseData)
     {
         Result = FspFileSystemCanReplaceReparsePoint(