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dll: reparse point implementation: WIP

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This commit is contained in:
Bill Zissimopoulos
2016-08-19 10:24:03 -07:00
parent 499a0cb866
commit 7ffc60f512
5 changed files with 398 additions and 84 deletions
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292
src/dll/fsop.c
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@ -121,8 +121,9 @@ FSP_API NTSTATUS FspFileSystemOpLeave(FSP_FILE_SYSTEM *FileSystem,
}
static inline
NTSTATUS FspFileSystemResolveReparsePoints(FSP_FILE_SYSTEM *FileSystem,
FSP_FSCTL_TRANSACT_REQ *Request, FSP_FSCTL_TRANSACT_RSP *Response)
NTSTATUS FspFileSystemCallResolveReparsePoints(FSP_FILE_SYSTEM *FileSystem,
FSP_FSCTL_TRANSACT_REQ *Request, FSP_FSCTL_TRANSACT_RSP *Response,
UINT32 ReparsePointIndex)
{
NTSTATUS Result = STATUS_INVALID_DEVICE_REQUEST;
IO_STATUS_BLOCK IoStatus;
@ -134,12 +135,27 @@ NTSTATUS FspFileSystemResolveReparsePoints(FSP_FILE_SYSTEM *FileSystem,
Size = FSP_FSCTL_TRANSACT_RSP_SIZEMAX - FIELD_OFFSET(FSP_FSCTL_TRANSACT_RSP, Buffer);
Result = FileSystem->Interface->ResolveReparsePoints(FileSystem,
(PWSTR)Request->Buffer,
ReparsePointIndex,
!!(Request->Req.Create.CreateOptions & FILE_OPEN_REPARSE_POINT),
&IoStatus,
Response->Buffer,
&Size);
if (STATUS_REPARSE == Result)
if (NT_SUCCESS(Result))
{
Result = STATUS_REPARSE;
Response->IoStatus.Information = (UINT32)IoStatus.Information;
if (0/*IO_REPARSE*/ == IoStatus.Information)
{
Response->Rsp.Create.Reparse.FileName.Offset = 0;
Response->Rsp.Create.Reparse.FileName.Size = (UINT16)Size;
}
else
{
Response->Rsp.Create.Reparse.Data.Offset = 0;
Response->Rsp.Create.Reparse.Data.Size = (UINT16)Size;
}
}
}
return Result;
@ -167,7 +183,10 @@ NTSTATUS FspFileSystemCreateCheck(FSP_FILE_SYSTEM *FileSystem,
FILE_ADD_SUBDIRECTORY : FILE_ADD_FILE,
PGrantedAccess, PSecurityDescriptor);
if (STATUS_REPARSE == Result)
Result = FspFileSystemResolveReparsePoints(FileSystem, Request, Response);
{
Result = FspFileSystemCallResolveReparsePoints(FileSystem, Request, Response, *PGrantedAccess);
*PGrantedAccess = 0;
}
else if (NT_SUCCESS(Result))
{
*PGrantedAccess = (MAXIMUM_ALLOWED & Request->Req.Create.DesiredAccess) ?
@ -199,7 +218,10 @@ NTSTATUS FspFileSystemOpenCheck(FSP_FILE_SYSTEM *FileSystem,
((Request->Req.Create.CreateOptions & FILE_DELETE_ON_CLOSE) ? DELETE : 0),
PGrantedAccess);
if (STATUS_REPARSE == Result)
Result = FspFileSystemResolveReparsePoints(FileSystem, Request, Response);
{
Result = FspFileSystemCallResolveReparsePoints(FileSystem, Request, Response, *PGrantedAccess);
*PGrantedAccess = 0;
}
else if (NT_SUCCESS(Result))
{
if (0 == (Request->Req.Create.DesiredAccess & MAXIMUM_ALLOWED))
@ -234,7 +256,10 @@ NTSTATUS FspFileSystemOverwriteCheck(FSP_FILE_SYSTEM *FileSystem,
((Request->Req.Create.CreateOptions & FILE_DELETE_ON_CLOSE) ? DELETE : 0),
PGrantedAccess);
if (STATUS_REPARSE == Result)
Result = FspFileSystemResolveReparsePoints(FileSystem, Request, Response);
{
Result = FspFileSystemCallResolveReparsePoints(FileSystem, Request, Response, *PGrantedAccess);
*PGrantedAccess = 0;
}
else if (NT_SUCCESS(Result))
{
if (0 == (Request->Req.Create.DesiredAccess & MAXIMUM_ALLOWED))
@ -260,7 +285,10 @@ NTSTATUS FspFileSystemOpenTargetDirectoryCheck(FSP_FILE_SYSTEM *FileSystem,
Result = FspAccessCheck(FileSystem, Request, TRUE, TRUE, Request->Req.Create.DesiredAccess,
PGrantedAccess);
if (STATUS_REPARSE == Result)
Result = FspFileSystemResolveReparsePoints(FileSystem, Request, Response);
{
Result = FspFileSystemCallResolveReparsePoints(FileSystem, Request, Response, *PGrantedAccess);
*PGrantedAccess = 0;
}
return Result;
}
@ -894,7 +922,7 @@ FSP_API NTSTATUS FspFileSystemOpFileSystemControl(FSP_FILE_SYSTEM *FileSystem,
FSP_FSCTL_TRANSACT_REQ *Request, FSP_FSCTL_TRANSACT_RSP *Response)
{
NTSTATUS Result;
PREPARSE_DATA_BUFFER SymlinkReparseData;
PREPARSE_DATA_BUFFER ReparseData;
SIZE_T Offset, Size;
Result = STATUS_INVALID_DEVICE_REQUEST;
@ -903,42 +931,39 @@ FSP_API NTSTATUS FspFileSystemOpFileSystemControl(FSP_FILE_SYSTEM *FileSystem,
case FSCTL_GET_REPARSE_POINT:
if (0 != FileSystem->Interface->GetReparsePoint)
{
SymlinkReparseData = (PREPARSE_DATA_BUFFER)Response->Buffer;
memset(SymlinkReparseData, 0, sizeof *SymlinkReparseData);
ReparseData = (PREPARSE_DATA_BUFFER)Response->Buffer;
memset(ReparseData, 0,
FIELD_OFFSET(REPARSE_DATA_BUFFER, SymbolicLinkReparseBuffer.PathBuffer));
if (FileSystem->ReparsePointsSymbolicLinks)
{
Size = FSP_FSCTL_TRANSACT_RSP_SIZEMAX - FIELD_OFFSET(FSP_FSCTL_TRANSACT_RSP, Buffer) -
sizeof(*SymlinkReparseData);
FIELD_OFFSET(REPARSE_DATA_BUFFER, SymbolicLinkReparseBuffer.PathBuffer);
Result = FileSystem->Interface->GetReparsePoint(FileSystem, Request,
(PVOID)Request->Req.FileSystemControl.UserContext,
(PWSTR)Request->Buffer,
SymlinkReparseData->SymbolicLinkReparseBuffer.PathBuffer,
ReparseData->SymbolicLinkReparseBuffer.PathBuffer,
&Size);
if (NT_SUCCESS(Result))
{
Offset = 0;
if (Size > 4 * sizeof(WCHAR) &&
'\\' == SymlinkReparseData->SymbolicLinkReparseBuffer.PathBuffer[0] &&
'?' == SymlinkReparseData->SymbolicLinkReparseBuffer.PathBuffer[1] &&
'?' == SymlinkReparseData->SymbolicLinkReparseBuffer.PathBuffer[2] &&
'\\' == SymlinkReparseData->SymbolicLinkReparseBuffer.PathBuffer[3])
'\\' == ReparseData->SymbolicLinkReparseBuffer.PathBuffer[0] &&
'?' == ReparseData->SymbolicLinkReparseBuffer.PathBuffer[1] &&
'?' == ReparseData->SymbolicLinkReparseBuffer.PathBuffer[2] &&
'\\' == ReparseData->SymbolicLinkReparseBuffer.PathBuffer[3])
Offset = 4 * sizeof(WCHAR);
SymlinkReparseData->ReparseTag = IO_REPARSE_TAG_SYMLINK;
SymlinkReparseData->ReparseDataLength = (USHORT)(
ReparseData->ReparseTag = IO_REPARSE_TAG_SYMLINK;
ReparseData->ReparseDataLength = (USHORT)(
FIELD_OFFSET(REPARSE_DATA_BUFFER, SymbolicLinkReparseBuffer.PathBuffer) -
FIELD_OFFSET(REPARSE_DATA_BUFFER, SymbolicLinkReparseBuffer) +
Size);
SymlinkReparseData->SymbolicLinkReparseBuffer.SubstituteNameOffset =
0;
SymlinkReparseData->SymbolicLinkReparseBuffer.SubstituteNameLength =
(USHORT)Size;
SymlinkReparseData->SymbolicLinkReparseBuffer.PrintNameOffset =
(USHORT)Offset;
SymlinkReparseData->SymbolicLinkReparseBuffer.PrintNameLength =
(USHORT)(Size - Offset);
SymlinkReparseData->SymbolicLinkReparseBuffer.Flags = 0 == Offset ?
ReparseData->SymbolicLinkReparseBuffer.SubstituteNameOffset = 0;
ReparseData->SymbolicLinkReparseBuffer.SubstituteNameLength = (USHORT)Size;
ReparseData->SymbolicLinkReparseBuffer.PrintNameOffset = (USHORT)Offset;
ReparseData->SymbolicLinkReparseBuffer.PrintNameLength = (USHORT)(Size - Offset);
ReparseData->SymbolicLinkReparseBuffer.Flags = 0 == Offset ?
0 : SYMLINK_FLAG_RELATIVE;
Response->Rsp.FileSystemControl.Buffer.Size = (UINT16)Size;
@ -949,7 +974,7 @@ FSP_API NTSTATUS FspFileSystemOpFileSystemControl(FSP_FILE_SYSTEM *FileSystem,
Size = FSP_FSCTL_TRANSACT_RSP_SIZEMAX - FIELD_OFFSET(FSP_FSCTL_TRANSACT_RSP, Buffer);
Result = FileSystem->Interface->GetReparsePoint(FileSystem, Request,
(PVOID)Request->Req.FileSystemControl.UserContext,
(PWSTR)Request->Buffer, SymlinkReparseData, &Size);
(PWSTR)Request->Buffer, ReparseData, &Size);
if (NT_SUCCESS(Result))
Response->Rsp.FileSystemControl.Buffer.Size = (UINT16)Size;
}
@ -958,7 +983,7 @@ FSP_API NTSTATUS FspFileSystemOpFileSystemControl(FSP_FILE_SYSTEM *FileSystem,
case FSCTL_SET_REPARSE_POINT:
if (0 != FileSystem->Interface->SetReparsePoint)
{
SymlinkReparseData = (PREPARSE_DATA_BUFFER)
ReparseData = (PREPARSE_DATA_BUFFER)
(Request->Buffer + Request->Req.FileSystemControl.Buffer.Offset);
if (FileSystem->ReparsePointsSymbolicLinks)
@ -966,15 +991,15 @@ FSP_API NTSTATUS FspFileSystemOpFileSystemControl(FSP_FILE_SYSTEM *FileSystem,
Result = FileSystem->Interface->SetReparsePoint(FileSystem, Request,
(PVOID)Request->Req.FileSystemControl.UserContext,
(PWSTR)Request->Buffer,
SymlinkReparseData->SymbolicLinkReparseBuffer.PathBuffer +
SymlinkReparseData->SymbolicLinkReparseBuffer.SubstituteNameOffset / sizeof(WCHAR),
SymlinkReparseData->SymbolicLinkReparseBuffer.SubstituteNameLength);
ReparseData->SymbolicLinkReparseBuffer.PathBuffer +
ReparseData->SymbolicLinkReparseBuffer.SubstituteNameOffset / sizeof(WCHAR),
ReparseData->SymbolicLinkReparseBuffer.SubstituteNameLength);
}
else
Result = FileSystem->Interface->SetReparsePoint(FileSystem, Request,
(PVOID)Request->Req.FileSystemControl.UserContext,
(PWSTR)Request->Buffer,
SymlinkReparseData,
ReparseData,
Request->Req.FileSystemControl.Buffer.Size);
}
break;
@ -1053,3 +1078,204 @@ FSP_API BOOLEAN FspFileSystemAddDirInfo(FSP_FSCTL_DIR_INFO *DirInfo,
return TRUE;
}
FSP_API BOOLEAN FspFileSystemFindReparsePoint(FSP_FILE_SYSTEM *FileSystem,
NTSTATUS (*GetReparsePointByName)(
FSP_FILE_SYSTEM *FileSystem, PVOID Context, PWSTR FileName, PVOID Buffer, PSIZE_T PSize),
PVOID Context,
PWSTR FileName, PUINT32 PReparsePointIndex)
{
PWSTR p, lastp;
NTSTATUS Result;
p = FileName;
for (;;)
{
while (L'\\' == *p)
p++;
lastp = p;
while (L'\\' != *p)
{
if (L'\0' == *p)
return FALSE;
p++;
}
*p = L'\0';
Result = GetReparsePointByName(FileSystem, Context, FileName, 0, 0);
*p = L'\\';
if (!NT_SUCCESS(Result))
return FALSE;
else
{
if (0 != PReparsePointIndex)
*PReparsePointIndex = (ULONG)(lastp - FileName);
return TRUE;
}
}
return FALSE;
}
FSP_API NTSTATUS FspFileSystemResolveReparsePoints(FSP_FILE_SYSTEM *FileSystem,
NTSTATUS (*GetReparsePointByName)(
FSP_FILE_SYSTEM *FileSystem, PVOID Context, PWSTR FileName, PVOID Buffer, PSIZE_T PSize),
PVOID Context,
PWSTR FileName, UINT32 ReparsePointIndex, BOOLEAN OpenReparsePoint,
PIO_STATUS_BLOCK PIoStatus, PVOID Buffer, PSIZE_T PSize)
{
WCHAR c, *p, *lastp;
PWSTR TargetPath, TargetPathEnd, TargetLink;
union
{
REPARSE_DATA_BUFFER V;
UINT8 B[FIELD_OFFSET(REPARSE_DATA_BUFFER, SymbolicLinkReparseBuffer.PathBuffer) +
/* assumption: the substitute and print paths are stored in the same buffer */
FSP_FSCTL_TRANSACT_PATH_SIZEMAX];
} ReparseDataBuf;
PREPARSE_DATA_BUFFER ReparseData = &ReparseDataBuf.V;
SIZE_T Size, MaxTries = 32;
NTSTATUS Result;
TargetPath = Buffer;
TargetPathEnd = TargetPath + *PSize / sizeof(WCHAR);
Size = (lstrlenW(FileName) + 1) * sizeof(WCHAR);
if (Size > *PSize)
return STATUS_OBJECT_NAME_INVALID;
memcpy(TargetPath, FileName, Size);
p = TargetPath + ReparsePointIndex;
c = *p;
for (;;)
{
while (L'\\' == *p)
p++;
lastp = p;
while (L'\\' != *p)
{
if (L'\0' == *p)
{
if (!OpenReparsePoint)
goto exit;
OpenReparsePoint = FALSE;
break;
}
p++;
}
/* handle dot and dotdot! */
if (L'.' == lastp[0])
{
if (p == lastp + 1)
/* dot */
continue;
if (L'.' == lastp[1] && p == lastp + 1)
{
/* dotdot */
p = lastp;
while (TargetPath < p)
{
p--;
if (L'\\' != *p)
break;
}
while (TargetPath < p)
{
p--;
if (L'\\' == *p)
break;
}
continue;
}
}
c = *p;
*p = '\0';
if (FileSystem->ReparsePointsSymbolicLinks)
{
Size = FSP_FSCTL_TRANSACT_PATH_SIZEMAX;
Result = GetReparsePointByName(FileSystem, Context, TargetPath,
ReparseData->SymbolicLinkReparseBuffer.PathBuffer, &Size);
}
else
{
Size = sizeof ReparseDataBuf;
Result = GetReparsePointByName(FileSystem, Context, TargetPath,
ReparseData, &Size);
}
*p = c;
if (STATUS_NOT_A_REPARSE_POINT == Result)
/* it was not a reparse point; continue */
continue;
else if (!NT_SUCCESS(Result))
return Result;
/* found a reparse point */
if (0 == --MaxTries)
return STATUS_REPARSE_POINT_NOT_RESOLVED;
if (FileSystem->ReparsePointsSymbolicLinks)
TargetLink = ReparseData->SymbolicLinkReparseBuffer.PathBuffer;
else
{
if (IO_REPARSE_TAG_SYMLINK == ReparseData->ReparseTag)
{
TargetLink = ReparseData->SymbolicLinkReparseBuffer.PathBuffer +
ReparseData->SymbolicLinkReparseBuffer.SubstituteNameOffset;
Size = ReparseData->SymbolicLinkReparseBuffer.SubstituteNameLength;
}
else
{
/* not a symlink; return the full reparse point! */
if (Size > *PSize)
return STATUS_OBJECT_NAME_INVALID;
memcpy(Buffer, ReparseData, Size);
goto no_symlink_exit;
}
}
if (Size > 4 * sizeof(WCHAR) &&
'\\' == TargetLink[0] &&
'?' == TargetLink[1] &&
'?' == TargetLink[2] &&
'\\' == TargetLink[3])
{
/* absolute symlink; replace whole path */
if (Size > *PSize)
return STATUS_OBJECT_NAME_INVALID;
memcpy(TargetPath, TargetLink, Size);
p = TargetPath + Size / sizeof(WCHAR);
/* absolute symlinks on Windows are in NT namespace; send to FSD for further processing */
goto exit;
}
else
{
/* relative symlink; replace last path component seen */
if (Size + sizeof(WCHAR) > (TargetPathEnd - lastp) * sizeof(WCHAR))
return STATUS_OBJECT_NAME_INVALID;
memcpy(lastp, TargetLink, Size);
lastp[Size / sizeof(WCHAR)] = L'\0';
p = lastp;
}
}
exit:
*PSize = (PUINT8)p - (PUINT8)TargetPath;
PIoStatus->Status = STATUS_REPARSE;
PIoStatus->Information = 0/*IO_REPARSE*/;
return STATUS_REPARSE;
no_symlink_exit:
*PSize = Size;
PIoStatus->Status = STATUS_REPARSE;
PIoStatus->Information = ReparseData->ReparseTag;
return STATUS_REPARSE;
}