/** @file | |
EFI_FILE_PROTOCOL.SetInfo() member function for the Virtio Filesystem driver. | |
Copyright (C) 2020, Red Hat, Inc. | |
SPDX-License-Identifier: BSD-2-Clause-Patent | |
**/ | |
#include <Guid/FileSystemInfo.h> // gEfiFileSystemInfoGuid | |
#include <Guid/FileSystemVolumeLabelInfo.h> // gEfiFileSystemVolumeLabelInfo... | |
#include <Library/BaseLib.h> // StrCmp() | |
#include <Library/BaseMemoryLib.h> // CompareGuid() | |
#include <Library/MemoryAllocationLib.h> // FreePool() | |
#include "VirtioFsDxe.h" | |
/** | |
Validate a buffer that the EFI_FILE_PROTOCOL.SetInfo() caller passes in for a | |
particular InformationType GUID. | |
The structure to be validated is supposed to end with a variable-length, | |
NUL-terminated CHAR16 Name string. | |
@param[in] SizeByProtocolCaller The BufferSize parameter as provided by the | |
EFI_FILE_PROTOCOL.SetInfo() caller. | |
@param[in] MinimumStructSize The minimum structure size that is required | |
for the given InformationType GUID, | |
including a single CHAR16 element from the | |
trailing Name field. | |
@param[in] IsSizeByInfoPresent TRUE if and only if the expected structure | |
starts with a UINT64 Size field that reports | |
the actual structure size. | |
@param[in] Buffer The Buffer parameter as provided by the | |
EFI_FILE_PROTOCOL.SetInfo() caller. | |
@retval EFI_SUCCESS Validation successful, Buffer is well-formed. | |
@retval EFI_BAD_BUFFER_SIZE The EFI_FILE_PROTOCOL.SetInfo() | |
caller provided a BufferSize that is smaller | |
than the minimum structure size required for | |
the given InformationType GUID. | |
@retval EFI_INVALID_PARAMETER IsSizeByInfoPresent is TRUE, and the leading | |
UINT64 Size field does not match the | |
EFI_FILE_PROTOCOL.SetInfo() caller-provided | |
BufferSize. | |
@retval EFI_INVALID_PARAMETER The trailing Name field does not consist of a | |
whole multiple of CHAR16 elements. | |
@retval EFI_INVALID_PARAMETER The trailing Name field is not NUL-terminated. | |
**/ | |
STATIC | |
EFI_STATUS | |
ValidateInfoStructure ( | |
IN UINTN SizeByProtocolCaller, | |
IN UINTN MinimumStructSize, | |
IN BOOLEAN IsSizeByInfoPresent, | |
IN VOID *Buffer | |
) | |
{ | |
UINTN NameFieldByteOffset; | |
UINTN NameFieldBytes; | |
UINTN NameFieldChar16s; | |
CHAR16 *NameField; | |
// | |
// Make sure the internal function asking for validation passes in sane | |
// values. | |
// | |
ASSERT (MinimumStructSize >= sizeof (CHAR16)); | |
NameFieldByteOffset = MinimumStructSize - sizeof (CHAR16); | |
if (IsSizeByInfoPresent) { | |
ASSERT (MinimumStructSize >= sizeof (UINT64) + sizeof (CHAR16)); | |
ASSERT (NameFieldByteOffset >= sizeof (UINT64)); | |
} | |
// | |
// Check whether the protocol caller provided enough bytes for the minimum | |
// size of this info structure. | |
// | |
if (SizeByProtocolCaller < MinimumStructSize) { | |
return EFI_BAD_BUFFER_SIZE; | |
} | |
// | |
// If the info structure starts with a UINT64 Size field, check if that | |
// agrees with the protocol caller-provided size. | |
// | |
if (IsSizeByInfoPresent) { | |
UINT64 *SizeByInfo; | |
SizeByInfo = Buffer; | |
if (*SizeByInfo != SizeByProtocolCaller) { | |
return EFI_INVALID_PARAMETER; | |
} | |
} | |
// | |
// The CHAR16 Name field at the end of the structure must have an even number | |
// of bytes. | |
// | |
// The subtraction below cannot underflow, and yields at least | |
// sizeof(CHAR16). | |
// | |
ASSERT (SizeByProtocolCaller >= NameFieldByteOffset); | |
NameFieldBytes = SizeByProtocolCaller - NameFieldByteOffset; | |
ASSERT (NameFieldBytes >= sizeof (CHAR16)); | |
if (NameFieldBytes % sizeof (CHAR16) != 0) { | |
return EFI_INVALID_PARAMETER; | |
} | |
// | |
// The CHAR16 Name field at the end of the structure must be NUL-terminated. | |
// | |
NameFieldChar16s = NameFieldBytes / sizeof (CHAR16); | |
ASSERT (NameFieldChar16s >= 1); | |
NameField = (CHAR16 *)((UINT8 *)Buffer + NameFieldByteOffset); | |
if (NameField[NameFieldChar16s - 1] != L'\0') { | |
return EFI_INVALID_PARAMETER; | |
} | |
return EFI_SUCCESS; | |
} | |
/** | |
Rename a VIRTIO_FS_FILE as requested in EFI_FILE_INFO.FileName. | |
@param[in,out] VirtioFsFile The VIRTIO_FS_FILE to rename. | |
@param[in] NewFileName The new file name requested by | |
EFI_FILE_PROTOCOL.SetInfo(). | |
@retval EFI_SUCCESS The canonical format destination path that is | |
determined from the input value of | |
VirtioFsFile->CanonicalPathname and from | |
NewFileName is identical to the input value of | |
VirtioFsFile->CanonicalPathname. This means that | |
EFI_FILE_INFO does not constitute a rename | |
request. VirtioFsFile has not been changed. | |
@retval EFI_SUCCESS VirtioFsFile has been renamed. | |
VirtioFsFile->CanonicalPathname has assumed the | |
destination pathname in canonical format. | |
@retval EFI_ACCESS_DENIED VirtioFsFile refers to the root directory, and | |
NewFileName expresses an actual rename/move | |
request. | |
@retval EFI_ACCESS_DENIED VirtioFsFile is the (possibly indirect) parent | |
directory of at least one other VIRTIO_FS_FILE | |
that is open for the same Virtio Filesystem | |
(identified by VirtioFsFile->OwnerFs). Renaming | |
VirtioFsFile would invalidate the canonical | |
pathnames of those VIRTIO_FS_FILE instances; | |
therefore the request has been rejected. | |
@retval EFI_ACCESS_DENIED VirtioFsFile is not open for writing, but | |
NewFileName expresses an actual rename/move | |
request. | |
@retval EFI_NOT_FOUND At least one dot-dot component in NewFileName | |
attempted to escape the root directory. | |
@return Error codes propagated from underlying functions. | |
**/ | |
STATIC | |
EFI_STATUS | |
Rename ( | |
IN OUT VIRTIO_FS_FILE *VirtioFsFile, | |
IN CHAR16 *NewFileName | |
) | |
{ | |
VIRTIO_FS *VirtioFs; | |
EFI_STATUS Status; | |
CHAR8 *Destination; | |
BOOLEAN RootEscape; | |
UINT64 OldParentDirNodeId; | |
CHAR8 *OldLastComponent; | |
UINT64 NewParentDirNodeId; | |
CHAR8 *NewLastComponent; | |
VirtioFs = VirtioFsFile->OwnerFs; | |
// | |
// The root directory cannot be renamed. | |
// | |
if (AsciiStrCmp (VirtioFsFile->CanonicalPathname, "/") == 0) { | |
if (StrCmp (NewFileName, L"") == 0) { | |
// | |
// Not a rename request anyway. | |
// | |
return EFI_SUCCESS; | |
} | |
return EFI_ACCESS_DENIED; | |
} | |
// | |
// Compose the canonical pathname for the destination. | |
// | |
Status = VirtioFsComposeRenameDestination ( | |
VirtioFsFile->CanonicalPathname, | |
NewFileName, | |
&Destination, | |
&RootEscape | |
); | |
if (EFI_ERROR (Status)) { | |
return Status; | |
} | |
if (RootEscape) { | |
Status = EFI_NOT_FOUND; | |
goto FreeDestination; | |
} | |
// | |
// If the rename would leave VirtioFsFile->CanonicalPathname unchanged, then | |
// EFI_FILE_PROTOCOL.SetInfo() isn't asking for a rename actually. | |
// | |
if (AsciiStrCmp (VirtioFsFile->CanonicalPathname, Destination) == 0) { | |
Status = EFI_SUCCESS; | |
goto FreeDestination; | |
} | |
// | |
// Check if the rename would break the canonical pathnames of other | |
// VIRTIO_FS_FILE instances of the same VIRTIO_FS. | |
// | |
if (VirtioFsFile->IsDirectory) { | |
UINTN PathLen; | |
LIST_ENTRY *OpenFilesEntry; | |
PathLen = AsciiStrLen (VirtioFsFile->CanonicalPathname); | |
BASE_LIST_FOR_EACH (OpenFilesEntry, &VirtioFs->OpenFiles) { | |
VIRTIO_FS_FILE *OtherFile; | |
OtherFile = VIRTIO_FS_FILE_FROM_OPEN_FILES_ENTRY (OpenFilesEntry); | |
if ((OtherFile != VirtioFsFile) && | |
(AsciiStrnCmp ( | |
VirtioFsFile->CanonicalPathname, | |
OtherFile->CanonicalPathname, | |
PathLen | |
) == 0) && | |
((OtherFile->CanonicalPathname[PathLen] == '\0') || | |
(OtherFile->CanonicalPathname[PathLen] == '/'))) | |
{ | |
// | |
// OtherFile refers to the same directory as VirtioFsFile, or is a | |
// (possibly indirect) child of the directory referred to by | |
// VirtioFsFile. | |
// | |
Status = EFI_ACCESS_DENIED; | |
goto FreeDestination; | |
} | |
} | |
} | |
// | |
// From this point on, the file needs to be open for writing. | |
// | |
if (!VirtioFsFile->IsOpenForWriting) { | |
Status = EFI_ACCESS_DENIED; | |
goto FreeDestination; | |
} | |
// | |
// Split both source and destination canonical pathnames into (most specific | |
// parent directory, last component) pairs. | |
// | |
Status = VirtioFsLookupMostSpecificParentDir ( | |
VirtioFs, | |
VirtioFsFile->CanonicalPathname, | |
&OldParentDirNodeId, | |
&OldLastComponent | |
); | |
if (EFI_ERROR (Status)) { | |
goto FreeDestination; | |
} | |
Status = VirtioFsLookupMostSpecificParentDir ( | |
VirtioFs, | |
Destination, | |
&NewParentDirNodeId, | |
&NewLastComponent | |
); | |
if (EFI_ERROR (Status)) { | |
goto ForgetOldParentDirNodeId; | |
} | |
// | |
// Perform the rename. If the destination path exists, the rename will fail. | |
// | |
Status = VirtioFsFuseRename ( | |
VirtioFs, | |
OldParentDirNodeId, | |
OldLastComponent, | |
NewParentDirNodeId, | |
NewLastComponent | |
); | |
if (EFI_ERROR (Status)) { | |
goto ForgetNewParentDirNodeId; | |
} | |
// | |
// Swap in the new canonical pathname. | |
// | |
FreePool (VirtioFsFile->CanonicalPathname); | |
VirtioFsFile->CanonicalPathname = Destination; | |
Destination = NULL; | |
Status = EFI_SUCCESS; | |
// | |
// Fall through. | |
// | |
ForgetNewParentDirNodeId: | |
if (NewParentDirNodeId != VIRTIO_FS_FUSE_ROOT_DIR_NODE_ID) { | |
VirtioFsFuseForget (VirtioFs, NewParentDirNodeId); | |
} | |
ForgetOldParentDirNodeId: | |
if (OldParentDirNodeId != VIRTIO_FS_FUSE_ROOT_DIR_NODE_ID) { | |
VirtioFsFuseForget (VirtioFs, OldParentDirNodeId); | |
} | |
FreeDestination: | |
if (Destination != NULL) { | |
FreePool (Destination); | |
} | |
return Status; | |
} | |
/** | |
Update the attributes of a VIRTIO_FS_FILE as requested in EFI_FILE_INFO. | |
@param[in,out] VirtioFsFile The VIRTIO_FS_FILE to update the attributes of. | |
@param[in] NewFileInfo The new attributes requested by | |
EFI_FILE_PROTOCOL.SetInfo(). NewFileInfo->Size | |
and NewFileInfo->FileName are ignored. | |
@retval EFI_SUCCESS No attributes had to be updated. | |
@retval EFI_SUCCESS The required set of attribute updates has been | |
determined and performed successfully. | |
@retval EFI_ACCESS_DENIED NewFileInfo requests an update to a property | |
different from the EFI_FILE_READ_ONLY bit in the | |
Attribute field, but VirtioFsFile is not open for | |
writing. | |
@return Error codes propagated from underlying functions. | |
**/ | |
STATIC | |
EFI_STATUS | |
UpdateAttributes ( | |
IN OUT VIRTIO_FS_FILE *VirtioFsFile, | |
IN EFI_FILE_INFO *NewFileInfo | |
) | |
{ | |
VIRTIO_FS *VirtioFs; | |
EFI_STATUS Status; | |
VIRTIO_FS_FUSE_ATTRIBUTES_RESPONSE FuseAttr; | |
EFI_FILE_INFO FileInfo; | |
BOOLEAN UpdateFileSize; | |
UINT64 FileSize; | |
BOOLEAN UpdateAtime; | |
BOOLEAN UpdateMtime; | |
UINT64 Atime; | |
UINT64 Mtime; | |
BOOLEAN UpdateMode; | |
UINT32 Mode; | |
VirtioFs = VirtioFsFile->OwnerFs; | |
// | |
// Fetch the current attributes first, so we can build the difference between | |
// them and NewFileInfo. | |
// | |
Status = VirtioFsFuseGetAttr (VirtioFs, VirtioFsFile->NodeId, &FuseAttr); | |
if (EFI_ERROR (Status)) { | |
return Status; | |
} | |
Status = VirtioFsFuseAttrToEfiFileInfo (&FuseAttr, &FileInfo); | |
if (EFI_ERROR (Status)) { | |
return Status; | |
} | |
// | |
// Collect the updates. | |
// | |
if (VirtioFsFile->IsDirectory) { | |
UpdateFileSize = FALSE; | |
} else { | |
VirtioFsGetFuseSizeUpdate ( | |
&FileInfo, | |
NewFileInfo, | |
&UpdateFileSize, | |
&FileSize | |
); | |
} | |
Status = VirtioFsGetFuseTimeUpdates ( | |
&FileInfo, | |
NewFileInfo, | |
&UpdateAtime, | |
&UpdateMtime, | |
&Atime, | |
&Mtime | |
); | |
if (EFI_ERROR (Status)) { | |
return Status; | |
} | |
Status = VirtioFsGetFuseModeUpdate ( | |
&FileInfo, | |
NewFileInfo, | |
&UpdateMode, | |
&Mode | |
); | |
if (EFI_ERROR (Status)) { | |
return Status; | |
} | |
// | |
// If no attribute updates are necessary, we're done. | |
// | |
if (!UpdateFileSize && !UpdateAtime && !UpdateMtime && !UpdateMode) { | |
return EFI_SUCCESS; | |
} | |
// | |
// If the file is not open for writing, then only Mode may be updated (for | |
// toggling EFI_FILE_READ_ONLY). | |
// | |
if (!VirtioFsFile->IsOpenForWriting && | |
(UpdateFileSize || UpdateAtime || UpdateMtime)) | |
{ | |
return EFI_ACCESS_DENIED; | |
} | |
// | |
// Send the FUSE_SETATTR request now. | |
// | |
Status = VirtioFsFuseSetAttr ( | |
VirtioFs, | |
VirtioFsFile->NodeId, | |
UpdateFileSize ? &FileSize : NULL, | |
UpdateAtime ? &Atime : NULL, | |
UpdateMtime ? &Mtime : NULL, | |
UpdateMode ? &Mode : NULL | |
); | |
return Status; | |
} | |
/** | |
Process an EFI_FILE_INFO setting request. | |
**/ | |
STATIC | |
EFI_STATUS | |
SetFileInfo ( | |
IN EFI_FILE_PROTOCOL *This, | |
IN UINTN BufferSize, | |
IN VOID *Buffer | |
) | |
{ | |
VIRTIO_FS_FILE *VirtioFsFile; | |
EFI_STATUS Status; | |
EFI_FILE_INFO *FileInfo; | |
VirtioFsFile = VIRTIO_FS_FILE_FROM_SIMPLE_FILE (This); | |
// | |
// Validate if Buffer passes as EFI_FILE_INFO. | |
// | |
Status = ValidateInfoStructure ( | |
BufferSize, // SizeByProtocolCaller | |
OFFSET_OF ( | |
EFI_FILE_INFO, | |
FileName | |
) + sizeof (CHAR16), // MinimumStructSize | |
TRUE, // IsSizeByInfoPresent | |
Buffer | |
); | |
if (EFI_ERROR (Status)) { | |
return Status; | |
} | |
FileInfo = Buffer; | |
// | |
// Perform the rename/move request, if any. | |
// | |
Status = Rename (VirtioFsFile, FileInfo->FileName); | |
if (EFI_ERROR (Status)) { | |
return Status; | |
} | |
// | |
// Update any attributes requested. | |
// | |
Status = UpdateAttributes (VirtioFsFile, FileInfo); | |
// | |
// The UEFI spec does not speak about partial failure in | |
// EFI_FILE_PROTOCOL.SetInfo(); we won't try to roll back the rename (if | |
// there was one) in case the attribute updates fail. | |
// | |
return Status; | |
} | |
/** | |
Process an EFI_FILE_SYSTEM_INFO setting request. | |
**/ | |
STATIC | |
EFI_STATUS | |
SetFileSystemInfo ( | |
IN EFI_FILE_PROTOCOL *This, | |
IN UINTN BufferSize, | |
IN VOID *Buffer | |
) | |
{ | |
VIRTIO_FS_FILE *VirtioFsFile; | |
VIRTIO_FS *VirtioFs; | |
EFI_STATUS Status; | |
EFI_FILE_SYSTEM_INFO *FileSystemInfo; | |
VirtioFsFile = VIRTIO_FS_FILE_FROM_SIMPLE_FILE (This); | |
VirtioFs = VirtioFsFile->OwnerFs; | |
// | |
// Validate if Buffer passes as EFI_FILE_SYSTEM_INFO. | |
// | |
Status = ValidateInfoStructure ( | |
BufferSize, // SizeByProtocolCaller | |
OFFSET_OF ( | |
EFI_FILE_SYSTEM_INFO, | |
VolumeLabel | |
) + sizeof (CHAR16), // MinimumStructSize | |
TRUE, // IsSizeByInfoPresent | |
Buffer | |
); | |
if (EFI_ERROR (Status)) { | |
return Status; | |
} | |
FileSystemInfo = Buffer; | |
// | |
// EFI_FILE_SYSTEM_INFO fields other than VolumeLabel cannot be changed, per | |
// spec. | |
// | |
// If the label is being changed to its current value, report success; | |
// otherwise, reject the request, as the Virtio Filesystem device does not | |
// support changing the label. | |
// | |
if (StrCmp (FileSystemInfo->VolumeLabel, VirtioFs->Label) == 0) { | |
return EFI_SUCCESS; | |
} | |
return EFI_WRITE_PROTECTED; | |
} | |
/** | |
Process an EFI_FILE_SYSTEM_VOLUME_LABEL setting request. | |
**/ | |
STATIC | |
EFI_STATUS | |
SetFileSystemVolumeLabelInfo ( | |
IN EFI_FILE_PROTOCOL *This, | |
IN UINTN BufferSize, | |
IN VOID *Buffer | |
) | |
{ | |
VIRTIO_FS_FILE *VirtioFsFile; | |
VIRTIO_FS *VirtioFs; | |
EFI_STATUS Status; | |
EFI_FILE_SYSTEM_VOLUME_LABEL *FileSystemVolumeLabel; | |
VirtioFsFile = VIRTIO_FS_FILE_FROM_SIMPLE_FILE (This); | |
VirtioFs = VirtioFsFile->OwnerFs; | |
// | |
// Validate if Buffer passes as EFI_FILE_SYSTEM_VOLUME_LABEL. | |
// | |
Status = ValidateInfoStructure ( | |
BufferSize, // SizeByProtocolCaller | |
OFFSET_OF ( | |
EFI_FILE_SYSTEM_VOLUME_LABEL, | |
VolumeLabel | |
) + sizeof (CHAR16), // MinimumStructSize | |
FALSE, // IsSizeByInfoPresent | |
Buffer | |
); | |
if (EFI_ERROR (Status)) { | |
return Status; | |
} | |
FileSystemVolumeLabel = Buffer; | |
// | |
// If the label is being changed to its current value, report success; | |
// otherwise, reject the request, as the Virtio Filesystem device does not | |
// support changing the label. | |
// | |
if (StrCmp (FileSystemVolumeLabel->VolumeLabel, VirtioFs->Label) == 0) { | |
return EFI_SUCCESS; | |
} | |
return EFI_WRITE_PROTECTED; | |
} | |
EFI_STATUS | |
EFIAPI | |
VirtioFsSimpleFileSetInfo ( | |
IN EFI_FILE_PROTOCOL *This, | |
IN EFI_GUID *InformationType, | |
IN UINTN BufferSize, | |
IN VOID *Buffer | |
) | |
{ | |
if (CompareGuid (InformationType, &gEfiFileInfoGuid)) { | |
return SetFileInfo (This, BufferSize, Buffer); | |
} | |
if (CompareGuid (InformationType, &gEfiFileSystemInfoGuid)) { | |
return SetFileSystemInfo (This, BufferSize, Buffer); | |
} | |
if (CompareGuid (InformationType, &gEfiFileSystemVolumeLabelInfoIdGuid)) { | |
return SetFileSystemVolumeLabelInfo (This, BufferSize, Buffer); | |
} | |
return EFI_UNSUPPORTED; | |
} |