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audk/OvmfPkg/QemuKernelLoaderFsDxe/QemuKernelLoaderFsDxe.c

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/** @file
DXE driver to expose the 'kernel', 'initrd' and 'cmdline' blobs
provided by QEMU as files in an abstract file system
Copyright (C) 2014-2016, Red Hat, Inc.
Copyright (C) 2020, Arm, Limited.
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include <PiDxe.h>
#include <Guid/FileInfo.h>
#include <Guid/FileSystemInfo.h>
#include <Guid/FileSystemVolumeLabelInfo.h>
#include <Guid/LinuxEfiInitrdMedia.h>
#include <Guid/QemuKernelLoaderFsMedia.h>
#include <Library/BaseLib.h>
#include <Library/BaseMemoryLib.h>
#include <Library/BlobVerifierLib.h>
#include <Library/DebugLib.h>
#include <Library/DevicePathLib.h>
#include <Library/MemoryAllocationLib.h>
#include <Library/PrintLib.h>
#include <Library/QemuFwCfgLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/UefiRuntimeServicesTableLib.h>
#include <Protocol/DevicePath.h>
#include <Protocol/LoadFile2.h>
#include <Protocol/SimpleFileSystem.h>
//
// Static data that hosts the fw_cfg blobs and serves file requests.
//
typedef struct {
CHAR16 Name[48];
struct {
FIRMWARE_CONFIG_ITEM SizeKey;
FIRMWARE_CONFIG_ITEM DataKey;
UINT32 Size;
} FwCfgItem[2];
} KERNEL_BLOB_ITEMS;
typedef struct KERNEL_BLOB KERNEL_BLOB;
struct KERNEL_BLOB {
CHAR16 Name[48];
UINT32 Size;
UINT8 *Data;
KERNEL_BLOB *Next;
};
STATIC KERNEL_BLOB_ITEMS mKernelBlobItems[] = {
{
L"kernel",
{
{ QemuFwCfgItemKernelSetupSize, QemuFwCfgItemKernelSetupData, },
{ QemuFwCfgItemKernelSize, QemuFwCfgItemKernelData, },
}
}, {
L"initrd",
{
{ QemuFwCfgItemInitrdSize, QemuFwCfgItemInitrdData, },
}
}, {
L"cmdline",
{
{ QemuFwCfgItemCommandLineSize, QemuFwCfgItemCommandLineData, },
}
}
};
STATIC KERNEL_BLOB *mKernelBlobs;
STATIC UINT64 mKernelBlobCount;
STATIC UINT64 mKernelNamedBlobCount;
STATIC UINT64 mTotalBlobBytes;
//
// Device path for the handle that incorporates our "EFI stub filesystem".
//
#pragma pack (1)
typedef struct {
VENDOR_DEVICE_PATH VenMediaNode;
EFI_DEVICE_PATH_PROTOCOL EndNode;
} SINGLE_VENMEDIA_NODE_DEVPATH;
#pragma pack ()
STATIC CONST SINGLE_VENMEDIA_NODE_DEVPATH mFileSystemDevicePath = {
{
{
MEDIA_DEVICE_PATH, MEDIA_VENDOR_DP,
{ sizeof (VENDOR_DEVICE_PATH) }
},
QEMU_KERNEL_LOADER_FS_MEDIA_GUID
}, {
END_DEVICE_PATH_TYPE, END_ENTIRE_DEVICE_PATH_SUBTYPE,
{ sizeof (EFI_DEVICE_PATH_PROTOCOL) }
}
};
STATIC CONST SINGLE_VENMEDIA_NODE_DEVPATH mInitrdDevicePath = {
{
{
MEDIA_DEVICE_PATH, MEDIA_VENDOR_DP,
{ sizeof (VENDOR_DEVICE_PATH) }
},
LINUX_EFI_INITRD_MEDIA_GUID
}, {
END_DEVICE_PATH_TYPE, END_ENTIRE_DEVICE_PATH_SUBTYPE,
{ sizeof (EFI_DEVICE_PATH_PROTOCOL) }
}
};
//
// The "file in the EFI stub filesystem" abstraction.
//
STATIC EFI_TIME mInitTime;
#define STUB_FILE_SIG SIGNATURE_64 ('S', 'T', 'U', 'B', 'F', 'I', 'L', 'E')
typedef struct {
UINT64 Signature; // Carries STUB_FILE_SIG.
KERNEL_BLOB *Blob; // Index into mKernelBlob. KernelBlobTypeMax
// denotes the root directory of the filesystem.
UINT64 Position; // Byte position for regular files;
// next directory entry to return for the root
// directory.
EFI_FILE_PROTOCOL File; // Standard protocol interface.
} STUB_FILE;
#define STUB_FILE_FROM_FILE(FilePointer) \
CR (FilePointer, STUB_FILE, File, STUB_FILE_SIG)
//
// Protocol member functions for File.
//
/**
Opens a new file relative to the source file's location.
(Forward declaration.)
@param[in] This A pointer to the EFI_FILE_PROTOCOL instance that is
the file handle to the source location. This would
typically be an open handle to a directory.
@param[out] NewHandle A pointer to the location to return the opened handle
for the new file.
@param[in] FileName The Null-terminated string of the name of the file to
be opened. The file name may contain the following
path modifiers: "\", ".", and "..".
@param[in] OpenMode The mode to open the file. The only valid
combinations that the file may be opened with are:
Read, Read/Write, or Create/Read/Write.
@param[in] Attributes Only valid for EFI_FILE_MODE_CREATE, in which case
these are the attribute bits for the newly created
file.
@retval EFI_SUCCESS The file was opened.
@retval EFI_NOT_FOUND The specified file could not be found on the
device.
@retval EFI_NO_MEDIA The device has no medium.
@retval EFI_MEDIA_CHANGED The device has a different medium in it or the
medium is no longer supported.
@retval EFI_DEVICE_ERROR The device reported an error.
@retval EFI_VOLUME_CORRUPTED The file system structures are corrupted.
@retval EFI_WRITE_PROTECTED An attempt was made to create a file, or open a
file for write when the media is
write-protected.
@retval EFI_ACCESS_DENIED The service denied access to the file.
@retval EFI_OUT_OF_RESOURCES Not enough resources were available to open the
file.
@retval EFI_VOLUME_FULL The volume is full.
**/
STATIC
EFI_STATUS
EFIAPI
QemuKernelStubFileOpen (
IN EFI_FILE_PROTOCOL *This,
OUT EFI_FILE_PROTOCOL **NewHandle,
IN CHAR16 *FileName,
IN UINT64 OpenMode,
IN UINT64 Attributes
);
/**
Closes a specified file handle.
@param[in] This A pointer to the EFI_FILE_PROTOCOL instance that is the file
handle to close.
@retval EFI_SUCCESS The file was closed.
**/
STATIC
EFI_STATUS
EFIAPI
QemuKernelStubFileClose (
IN EFI_FILE_PROTOCOL *This
)
{
FreePool (STUB_FILE_FROM_FILE (This));
return EFI_SUCCESS;
}
/**
Close and delete the file handle.
@param[in] This A pointer to the EFI_FILE_PROTOCOL instance that is the
handle to the file to delete.
@retval EFI_SUCCESS The file was closed and deleted, and the
handle was closed.
@retval EFI_WARN_DELETE_FAILURE The handle was closed, but the file was not
deleted.
**/
STATIC
EFI_STATUS
EFIAPI
QemuKernelStubFileDelete (
IN EFI_FILE_PROTOCOL *This
)
{
FreePool (STUB_FILE_FROM_FILE (This));
return EFI_WARN_DELETE_FAILURE;
}
/**
Helper function that formats an EFI_FILE_INFO structure into the
user-allocated buffer, for any valid KERNEL_BLOB (including NULL,
which stands for the root directory).
The interface follows the EFI_FILE_GET_INFO -- and for directories, the
EFI_FILE_READ -- interfaces.
@param[in] Blob The KERNEL_BLOB identifying the fw_cfg
blob backing the STUB_FILE that information is
being requested about. If Blob is NULL,
then information will be provided about the root
directory of the filesystem.
@param[in,out] BufferSize On input, the size of Buffer. On output, the
amount of data returned in Buffer. In both cases,
the size is measured in bytes.
@param[out] Buffer A pointer to the data buffer to return. The
buffer's type is EFI_FILE_INFO.
@retval EFI_SUCCESS The information was returned.
@retval EFI_BUFFER_TOO_SMALL BufferSize is too small to store the
EFI_FILE_INFO structure. BufferSize has been
updated with the size needed to complete the
request.
**/
STATIC
EFI_STATUS
QemuKernelBlobTypeToFileInfo (
IN KERNEL_BLOB *Blob,
IN OUT UINTN *BufferSize,
OUT VOID *Buffer
)
{
CONST CHAR16 *Name;
UINT64 FileSize;
UINT64 Attribute;
UINTN NameSize;
UINTN FileInfoSize;
EFI_FILE_INFO *FileInfo;
UINTN OriginalBufferSize;
if (Blob == NULL) {
//
// getting file info about the root directory
//
DEBUG ((DEBUG_INFO, "%a: file info: directory\n", __func__));
Name = L"";
FileSize = mKernelBlobCount;
Attribute = EFI_FILE_READ_ONLY | EFI_FILE_DIRECTORY;
} else {
DEBUG ((DEBUG_INFO, "%a: file info: \"%s\"\n", __func__, Blob->Name));
Name = Blob->Name;
FileSize = Blob->Size;
Attribute = EFI_FILE_READ_ONLY;
}
NameSize = (StrLen (Name) + 1) * 2;
FileInfoSize = SIZE_OF_EFI_FILE_INFO + NameSize;
OriginalBufferSize = *BufferSize;
*BufferSize = FileInfoSize;
if (OriginalBufferSize < *BufferSize) {
return EFI_BUFFER_TOO_SMALL;
}
FileInfo = (EFI_FILE_INFO *)Buffer;
FileInfo->Size = FileInfoSize;
FileInfo->FileSize = FileSize;
FileInfo->PhysicalSize = FileSize;
FileInfo->Attribute = Attribute;
CopyMem (&FileInfo->CreateTime, &mInitTime, sizeof mInitTime);
CopyMem (&FileInfo->LastAccessTime, &mInitTime, sizeof mInitTime);
CopyMem (&FileInfo->ModificationTime, &mInitTime, sizeof mInitTime);
CopyMem (FileInfo->FileName, Name, NameSize);
return EFI_SUCCESS;
}
STATIC
KERNEL_BLOB *
FindKernelBlob (
CHAR16 *FileName
)
{
KERNEL_BLOB *Blob;
for (Blob = mKernelBlobs; Blob != NULL; Blob = Blob->Next) {
if (StrCmp (FileName, Blob->Name) == 0) {
return Blob;
}
}
return NULL;
}
/**
Reads data from a file, or continues scanning a directory.
@param[in] This A pointer to the EFI_FILE_PROTOCOL instance that
is the file handle to read data from.
@param[in,out] BufferSize On input, the size of the Buffer. On output, the
amount of data returned in Buffer. In both cases,
the size is measured in bytes. If the read goes
beyond the end of the file, the read length is
truncated to the end of the file.
If This is a directory, the function reads the
directory entry at the current position and
returns the entry (as EFI_FILE_INFO) in Buffer. If
there are no more directory entries, the
BufferSize is set to zero on output.
@param[out] Buffer The buffer into which the data is read.
@retval EFI_SUCCESS Data was read.
@retval EFI_NO_MEDIA The device has no medium.
@retval EFI_DEVICE_ERROR The device reported an error.
@retval EFI_DEVICE_ERROR An attempt was made to read from a deleted
file.
@retval EFI_DEVICE_ERROR On entry, the current file position is beyond
the end of the file.
@retval EFI_VOLUME_CORRUPTED The file system structures are corrupted.
@retval EFI_BUFFER_TOO_SMALL The BufferSize is too small to store the
current directory entry as a EFI_FILE_INFO
structure. BufferSize has been updated with the
size needed to complete the request, and the
directory position has not been advanced.
**/
STATIC
EFI_STATUS
EFIAPI
QemuKernelStubFileRead (
IN EFI_FILE_PROTOCOL *This,
IN OUT UINTN *BufferSize,
OUT VOID *Buffer
)
{
STUB_FILE *StubFile;
KERNEL_BLOB *Blob;
UINT64 Left, Pos;
StubFile = STUB_FILE_FROM_FILE (This);
//
// Scanning the root directory?
//
if (StubFile->Blob == NULL) {
EFI_STATUS Status;
if (StubFile->Position == mKernelBlobCount) {
//
// Scanning complete.
//
*BufferSize = 0;
return EFI_SUCCESS;
}
for (Pos = 0, Blob = mKernelBlobs;
Pos < StubFile->Position;
Pos++, Blob = Blob->Next)
{
}
DEBUG ((DEBUG_INFO, "%a: file list: #%d \"%s\"\n", __func__, Pos, Blob->Name));
Status = QemuKernelBlobTypeToFileInfo (
Blob,
BufferSize,
Buffer
);
if (EFI_ERROR (Status)) {
return Status;
}
++StubFile->Position;
return EFI_SUCCESS;
}
//
// Reading a file.
//
Blob = StubFile->Blob;
if (StubFile->Position > Blob->Size) {
return EFI_DEVICE_ERROR;
}
Left = Blob->Size - StubFile->Position;
if (*BufferSize > Left) {
*BufferSize = (UINTN)Left;
}
if (Blob->Data != NULL) {
DEBUG ((DEBUG_INFO, "%a: file read: \"%s\", %d bytes\n", __func__, Blob->Name, *BufferSize));
CopyMem (Buffer, Blob->Data + StubFile->Position, *BufferSize);
}
StubFile->Position += *BufferSize;
return EFI_SUCCESS;
}
/**
Writes data to a file.
@param[in] This A pointer to the EFI_FILE_PROTOCOL instance that
is the file handle to write data to.
@param[in,out] BufferSize On input, the size of the Buffer. On output, the
amount of data actually written. In both cases,
the size is measured in bytes.
@param[in] Buffer The buffer of data to write.
@retval EFI_SUCCESS Data was written.
@retval EFI_UNSUPPORTED Writes to open directory files are not
supported.
@retval EFI_NO_MEDIA The device has no medium.
@retval EFI_DEVICE_ERROR The device reported an error.
@retval EFI_DEVICE_ERROR An attempt was made to write to a deleted file.
@retval EFI_VOLUME_CORRUPTED The file system structures are corrupted.
@retval EFI_WRITE_PROTECTED The file or medium is write-protected.
@retval EFI_ACCESS_DENIED The file was opened read only.
@retval EFI_VOLUME_FULL The volume is full.
**/
STATIC
EFI_STATUS
EFIAPI
QemuKernelStubFileWrite (
IN EFI_FILE_PROTOCOL *This,
IN OUT UINTN *BufferSize,
IN VOID *Buffer
)
{
STUB_FILE *StubFile;
StubFile = STUB_FILE_FROM_FILE (This);
return (StubFile->Blob == NULL) ?
EFI_UNSUPPORTED :
EFI_WRITE_PROTECTED;
}
/**
Returns a file's current position.
@param[in] This A pointer to the EFI_FILE_PROTOCOL instance that is the
file handle to get the current position on.
@param[out] Position The address to return the file's current position
value.
@retval EFI_SUCCESS The position was returned.
@retval EFI_UNSUPPORTED The request is not valid on open directories.
@retval EFI_DEVICE_ERROR An attempt was made to get the position from a
deleted file.
**/
STATIC
EFI_STATUS
EFIAPI
QemuKernelStubFileGetPosition (
IN EFI_FILE_PROTOCOL *This,
OUT UINT64 *Position
)
{
STUB_FILE *StubFile;
StubFile = STUB_FILE_FROM_FILE (This);
if (StubFile->Blob == NULL) {
return EFI_UNSUPPORTED;
}
*Position = StubFile->Position;
return EFI_SUCCESS;
}
/**
Sets a file's current position.
@param[in] This A pointer to the EFI_FILE_PROTOCOL instance that is the
file handle to set the requested position on.
@param[in] Position The byte position from the start of the file to set. For
regular files, MAX_UINT64 means "seek to end". For
directories, zero means "rewind directory scan".
@retval EFI_SUCCESS The position was set.
@retval EFI_UNSUPPORTED The seek request for nonzero is not valid on open
directories.
@retval EFI_DEVICE_ERROR An attempt was made to set the position of a
deleted file.
**/
STATIC
EFI_STATUS
EFIAPI
QemuKernelStubFileSetPosition (
IN EFI_FILE_PROTOCOL *This,
IN UINT64 Position
)
{
STUB_FILE *StubFile;
KERNEL_BLOB *Blob;
StubFile = STUB_FILE_FROM_FILE (This);
if (StubFile->Blob == NULL) {
if (Position == 0) {
//
// rewinding a directory scan is allowed
//
StubFile->Position = 0;
return EFI_SUCCESS;
}
return EFI_UNSUPPORTED;
}
//
// regular file seek
//
Blob = StubFile->Blob;
if (Position == MAX_UINT64) {
//
// seek to end
//
StubFile->Position = Blob->Size;
} else {
//
// absolute seek from beginning -- seeking past the end is allowed
//
StubFile->Position = Position;
}
return EFI_SUCCESS;
}
/**
Returns information about a file.
@param[in] This A pointer to the EFI_FILE_PROTOCOL instance
that is the file handle the requested
information is for.
@param[in] InformationType The type identifier GUID for the information
being requested. The following information
types are supported, storing the
corresponding structures in Buffer:
- gEfiFileInfoGuid: EFI_FILE_INFO
- gEfiFileSystemInfoGuid:
EFI_FILE_SYSTEM_INFO
- gEfiFileSystemVolumeLabelInfoIdGuid:
EFI_FILE_SYSTEM_VOLUME_LABEL
@param[in,out] BufferSize On input, the size of Buffer. On output, the
amount of data returned in Buffer. In both
cases, the size is measured in bytes.
@param[out] Buffer A pointer to the data buffer to return. The
buffer's type is indicated by
InformationType.
@retval EFI_SUCCESS The information was returned.
@retval EFI_UNSUPPORTED The InformationType is not known.
@retval EFI_NO_MEDIA The device has no medium.
@retval EFI_DEVICE_ERROR The device reported an error.
@retval EFI_VOLUME_CORRUPTED The file system structures are corrupted.
@retval EFI_BUFFER_TOO_SMALL The BufferSize is too small to store the
information structure requested by
InformationType. BufferSize has been updated
with the size needed to complete the request.
**/
STATIC
EFI_STATUS
EFIAPI
QemuKernelStubFileGetInfo (
IN EFI_FILE_PROTOCOL *This,
IN EFI_GUID *InformationType,
IN OUT UINTN *BufferSize,
OUT VOID *Buffer
)
{
CONST STUB_FILE *StubFile;
UINTN OriginalBufferSize;
StubFile = STUB_FILE_FROM_FILE (This);
if (CompareGuid (InformationType, &gEfiFileInfoGuid)) {
return QemuKernelBlobTypeToFileInfo (
StubFile->Blob,
BufferSize,
Buffer
);
}
OriginalBufferSize = *BufferSize;
if (CompareGuid (InformationType, &gEfiFileSystemInfoGuid)) {
EFI_FILE_SYSTEM_INFO *FileSystemInfo;
*BufferSize = sizeof *FileSystemInfo;
if (OriginalBufferSize < *BufferSize) {
return EFI_BUFFER_TOO_SMALL;
}
FileSystemInfo = (EFI_FILE_SYSTEM_INFO *)Buffer;
FileSystemInfo->Size = sizeof *FileSystemInfo;
FileSystemInfo->ReadOnly = TRUE;
FileSystemInfo->VolumeSize = mTotalBlobBytes;
FileSystemInfo->FreeSpace = 0;
FileSystemInfo->BlockSize = 1;
FileSystemInfo->VolumeLabel[0] = L'\0';
return EFI_SUCCESS;
}
if (CompareGuid (InformationType, &gEfiFileSystemVolumeLabelInfoIdGuid)) {
EFI_FILE_SYSTEM_VOLUME_LABEL *FileSystemVolumeLabel;
*BufferSize = sizeof *FileSystemVolumeLabel;
if (OriginalBufferSize < *BufferSize) {
return EFI_BUFFER_TOO_SMALL;
}
FileSystemVolumeLabel = (EFI_FILE_SYSTEM_VOLUME_LABEL *)Buffer;
FileSystemVolumeLabel->VolumeLabel[0] = L'\0';
return EFI_SUCCESS;
}
return EFI_UNSUPPORTED;
}
/**
Sets information about a file.
@param[in] File A pointer to the EFI_FILE_PROTOCOL instance that
is the file handle the information is for.
@param[in] InformationType The type identifier for the information being
set.
@param[in] BufferSize The size, in bytes, of Buffer.
@param[in] Buffer A pointer to the data buffer to write. The
buffer's type is indicated by InformationType.
@retval EFI_SUCCESS The information was set.
@retval EFI_UNSUPPORTED The InformationType is not known.
@retval EFI_NO_MEDIA The device has no medium.
@retval EFI_DEVICE_ERROR The device reported an error.
@retval EFI_VOLUME_CORRUPTED The file system structures are corrupted.
@retval EFI_WRITE_PROTECTED InformationType is EFI_FILE_INFO_ID and the
media is read-only.
@retval EFI_WRITE_PROTECTED InformationType is
EFI_FILE_PROTOCOL_SYSTEM_INFO_ID and the media
is read only.
@retval EFI_WRITE_PROTECTED InformationType is
EFI_FILE_SYSTEM_VOLUME_LABEL_ID and the media
is read-only.
@retval EFI_ACCESS_DENIED An attempt is made to change the name of a file
to a file that is already present.
@retval EFI_ACCESS_DENIED An attempt is being made to change the
EFI_FILE_DIRECTORY Attribute.
@retval EFI_ACCESS_DENIED An attempt is being made to change the size of
a directory.
@retval EFI_ACCESS_DENIED InformationType is EFI_FILE_INFO_ID and the
file was opened read-only and an attempt is
being made to modify a field other than
Attribute.
@retval EFI_VOLUME_FULL The volume is full.
@retval EFI_BAD_BUFFER_SIZE BufferSize is smaller than the size of the type
indicated by InformationType.
**/
STATIC
EFI_STATUS
EFIAPI
QemuKernelStubFileSetInfo (
IN EFI_FILE_PROTOCOL *This,
IN EFI_GUID *InformationType,
IN UINTN BufferSize,
IN VOID *Buffer
)
{
return EFI_WRITE_PROTECTED;
}
/**
Flushes all modified data associated with a file to a device.
@param [in] This A pointer to the EFI_FILE_PROTOCOL instance that is the
file handle to flush.
@retval EFI_SUCCESS The data was flushed.
@retval EFI_NO_MEDIA The device has no medium.
@retval EFI_DEVICE_ERROR The device reported an error.
@retval EFI_VOLUME_CORRUPTED The file system structures are corrupted.
@retval EFI_WRITE_PROTECTED The file or medium is write-protected.
@retval EFI_ACCESS_DENIED The file was opened read-only.
@retval EFI_VOLUME_FULL The volume is full.
**/
STATIC
EFI_STATUS
EFIAPI
QemuKernelStubFileFlush (
IN EFI_FILE_PROTOCOL *This
)
{
return EFI_WRITE_PROTECTED;
}
//
// External definition of the file protocol template.
//
STATIC CONST EFI_FILE_PROTOCOL mEfiFileProtocolTemplate = {
EFI_FILE_PROTOCOL_REVISION, // revision 1
QemuKernelStubFileOpen,
QemuKernelStubFileClose,
QemuKernelStubFileDelete,
QemuKernelStubFileRead,
QemuKernelStubFileWrite,
QemuKernelStubFileGetPosition,
QemuKernelStubFileSetPosition,
QemuKernelStubFileGetInfo,
QemuKernelStubFileSetInfo,
QemuKernelStubFileFlush,
NULL, // OpenEx, revision 2
NULL, // ReadEx, revision 2
NULL, // WriteEx, revision 2
NULL // FlushEx, revision 2
};
STATIC
EFI_STATUS
EFIAPI
QemuKernelStubFileOpen (
IN EFI_FILE_PROTOCOL *This,
OUT EFI_FILE_PROTOCOL **NewHandle,
IN CHAR16 *FileName,
IN UINT64 OpenMode,
IN UINT64 Attributes
)
{
CONST STUB_FILE *StubFile;
KERNEL_BLOB *Blob;
STUB_FILE *NewStubFile;
//
// We're read-only.
//
switch (OpenMode) {
case EFI_FILE_MODE_READ:
break;
case EFI_FILE_MODE_READ | EFI_FILE_MODE_WRITE:
case EFI_FILE_MODE_READ | EFI_FILE_MODE_WRITE | EFI_FILE_MODE_CREATE:
return EFI_WRITE_PROTECTED;
default:
return EFI_INVALID_PARAMETER;
}
//
// Only the root directory supports opening files in it.
//
StubFile = STUB_FILE_FROM_FILE (This);
if (StubFile->Blob != NULL) {
return EFI_UNSUPPORTED;
}
//
// Locate the file.
//
if (FileName[0] == '\\') {
// also accept absolute paths, i.e. '\kernel' for 'kernel'
FileName++;
}
Blob = FindKernelBlob (FileName);
if (Blob == NULL) {
DEBUG ((DEBUG_INFO, "%a: file not found: \"%s\"\n", __func__, FileName));
return EFI_NOT_FOUND;
} else {
DEBUG ((DEBUG_INFO, "%a: file opened: \"%s\"\n", __func__, FileName));
}
//
// Found it.
//
NewStubFile = AllocatePool (sizeof *NewStubFile);
if (NewStubFile == NULL) {
return EFI_OUT_OF_RESOURCES;
}
NewStubFile->Signature = STUB_FILE_SIG;
NewStubFile->Blob = Blob;
NewStubFile->Position = 0;
CopyMem (
&NewStubFile->File,
&mEfiFileProtocolTemplate,
sizeof mEfiFileProtocolTemplate
);
*NewHandle = &NewStubFile->File;
return EFI_SUCCESS;
}
//
// Protocol member functions for SimpleFileSystem.
//
/**
Open the root directory on a volume.
@param[in] This A pointer to the volume to open the root directory on.
@param[out] Root A pointer to the location to return the opened file handle
for the root directory in.
@retval EFI_SUCCESS The device was opened.
@retval EFI_UNSUPPORTED This volume does not support the requested file
system type.
@retval EFI_NO_MEDIA The device has no medium.
@retval EFI_DEVICE_ERROR The device reported an error.
@retval EFI_VOLUME_CORRUPTED The file system structures are corrupted.
@retval EFI_ACCESS_DENIED The service denied access to the file.
@retval EFI_OUT_OF_RESOURCES The volume was not opened due to lack of
resources.
@retval EFI_MEDIA_CHANGED The device has a different medium in it or the
medium is no longer supported. Any existing
file handles for this volume are no longer
valid. To access the files on the new medium,
the volume must be reopened with OpenVolume().
**/
STATIC
EFI_STATUS
EFIAPI
QemuKernelStubFileSystemOpenVolume (
IN EFI_SIMPLE_FILE_SYSTEM_PROTOCOL *This,
OUT EFI_FILE_PROTOCOL **Root
)
{
STUB_FILE *StubFile;
StubFile = AllocatePool (sizeof *StubFile);
if (StubFile == NULL) {
return EFI_OUT_OF_RESOURCES;
}
StubFile->Signature = STUB_FILE_SIG;
StubFile->Blob = NULL;
StubFile->Position = 0;
CopyMem (
&StubFile->File,
&mEfiFileProtocolTemplate,
sizeof mEfiFileProtocolTemplate
);
*Root = &StubFile->File;
return EFI_SUCCESS;
}
STATIC CONST EFI_SIMPLE_FILE_SYSTEM_PROTOCOL mFileSystem = {
EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_REVISION,
QemuKernelStubFileSystemOpenVolume
};
STATIC
EFI_STATUS
EFIAPI
QemuKernelInitrdLoadFile2 (
IN EFI_LOAD_FILE2_PROTOCOL *This,
IN EFI_DEVICE_PATH_PROTOCOL *FilePath,
IN BOOLEAN BootPolicy,
IN OUT UINTN *BufferSize,
OUT VOID *Buffer OPTIONAL
)
{
KERNEL_BLOB *InitrdBlob;
DEBUG ((DEBUG_INFO, "%a: initrd read\n", __func__));
InitrdBlob = FindKernelBlob (L"initrd");
ASSERT (InitrdBlob != NULL);
ASSERT (InitrdBlob->Size > 0);
if (BootPolicy) {
return EFI_UNSUPPORTED;
}
if ((BufferSize == NULL) || !IsDevicePathValid (FilePath, 0)) {
return EFI_INVALID_PARAMETER;
}
if ((FilePath->Type != END_DEVICE_PATH_TYPE) ||
(FilePath->SubType != END_ENTIRE_DEVICE_PATH_SUBTYPE))
{
return EFI_NOT_FOUND;
}
if ((Buffer == NULL) || (*BufferSize < InitrdBlob->Size)) {
*BufferSize = InitrdBlob->Size;
return EFI_BUFFER_TOO_SMALL;
}
CopyMem (Buffer, InitrdBlob->Data, InitrdBlob->Size);
*BufferSize = InitrdBlob->Size;
return EFI_SUCCESS;
}
STATIC CONST EFI_LOAD_FILE2_PROTOCOL mInitrdLoadFile2 = {
QemuKernelInitrdLoadFile2,
};
//
// Utility functions.
//
STATIC VOID
QemuKernelChunkedRead (
UINT8 *Dest,
UINT32 Bytes
)
{
UINT32 Chunk;
while (Bytes > 0) {
Chunk = (Bytes < SIZE_1MB) ? Bytes : SIZE_1MB;
QemuFwCfgReadBytes (Chunk, Dest);
Bytes -= Chunk;
Dest += Chunk;
}
}
/**
Populate a blob in mKernelBlob.
param[in,out] Blob Pointer to the KERNEL_BLOB_ITEMS that is
to be filled from fw_cfg.
@retval EFI_SUCCESS Blob has been populated. If fw_cfg reported a
size of zero for the blob, then Blob->Data has
been left unchanged.
@retval EFI_OUT_OF_RESOURCES Failed to allocate memory for Blob->Data.
**/
STATIC
EFI_STATUS
QemuKernelFetchBlob (
IN KERNEL_BLOB_ITEMS *BlobItems
)
{
UINT32 Size;
UINTN Idx;
UINT8 *ChunkData;
KERNEL_BLOB *Blob;
EFI_STATUS Status;
//
// Read blob size.
// Size != 0 -> use size as-is
// SizeKey != 0 -> read size from fw_cfg
// both are 0 -> unused entry
//
for (Size = 0, Idx = 0; Idx < ARRAY_SIZE (BlobItems->FwCfgItem); Idx++) {
if ((BlobItems->FwCfgItem[Idx].SizeKey == 0) &&
(BlobItems->FwCfgItem[Idx].Size == 0))
{
break;
}
if (BlobItems->FwCfgItem[Idx].SizeKey) {
QemuFwCfgSelectItem (BlobItems->FwCfgItem[Idx].SizeKey);
BlobItems->FwCfgItem[Idx].Size = QemuFwCfgRead32 ();
}
Size += BlobItems->FwCfgItem[Idx].Size;
}
if (Size == 0) {
return EFI_SUCCESS;
}
Blob = AllocatePool (sizeof (*Blob));
if (Blob->Data == NULL) {
return EFI_OUT_OF_RESOURCES;
}
ZeroMem (Blob, sizeof (*Blob));
//
// Read blob.
//
Status = StrCpyS (Blob->Name, sizeof (Blob->Name), BlobItems->Name);
ASSERT (!EFI_ERROR (Status));
Blob->Size = Size;
Blob->Data = AllocatePool (Blob->Size);
if (Blob->Data == NULL) {
DEBUG ((
DEBUG_ERROR,
"%a: failed to allocate %Ld bytes for \"%s\"\n",
__func__,
(INT64)Blob->Size,
Blob->Name
));
FreePool (Blob);
return EFI_OUT_OF_RESOURCES;
}
DEBUG ((
DEBUG_INFO,
"%a: loading %Ld bytes for \"%s\"\n",
__func__,
(INT64)Blob->Size,
Blob->Name
));
ChunkData = Blob->Data;
for (Idx = 0; Idx < ARRAY_SIZE (BlobItems->FwCfgItem); Idx++) {
if (BlobItems->FwCfgItem[Idx].DataKey == 0) {
break;
}
QemuFwCfgSelectItem (BlobItems->FwCfgItem[Idx].DataKey);
QemuKernelChunkedRead (ChunkData, BlobItems->FwCfgItem[Idx].Size);
ChunkData += BlobItems->FwCfgItem[Idx].Size;
}
Blob->Next = mKernelBlobs;
mKernelBlobs = Blob;
mKernelBlobCount++;
mTotalBlobBytes += Blob->Size;
return EFI_SUCCESS;
}
STATIC
EFI_STATUS
QemuKernelVerifyBlob (
CHAR16 *FileName,
EFI_STATUS FetchStatus
)
{
KERNEL_BLOB *Blob;
EFI_STATUS Status;
if ((StrCmp (FileName, L"kernel") != 0) &&
(StrCmp (FileName, L"initrd") != 0) &&
(StrCmp (FileName, L"cmdline") != 0))
{
return EFI_SUCCESS;
}
Blob = FindKernelBlob (FileName);
Status = VerifyBlob (
FileName,
Blob ? Blob->Data : NULL,
Blob ? Blob->Size : 0,
FetchStatus
);
return Status;
}
STATIC
EFI_STATUS
QemuKernelFetchNamedBlobs (
VOID
)
{
struct {
UINT32 FileSize;
UINT16 FileSelect;
UINT16 Reserved;
CHAR8 FileName[QEMU_FW_CFG_FNAME_SIZE];
} *DirEntry;
KERNEL_BLOB_ITEMS Items;
EFI_STATUS Status;
EFI_STATUS FetchStatus;
UINT32 Count;
UINT32 Idx;
QemuFwCfgSelectItem (QemuFwCfgItemFileDir);
Count = SwapBytes32 (QemuFwCfgRead32 ());
DirEntry = AllocatePool (sizeof (*DirEntry) * Count);
QemuFwCfgReadBytes (sizeof (*DirEntry) * Count, DirEntry);
for (Idx = 0; Idx < Count; ++Idx) {
if (AsciiStrnCmp (DirEntry[Idx].FileName, "etc/boot/", 9) != 0) {
continue;
}
ZeroMem (&Items, sizeof (Items));
UnicodeSPrint (Items.Name, sizeof (Items.Name), L"%a", DirEntry[Idx].FileName + 9);
Items.FwCfgItem[0].DataKey = SwapBytes16 (DirEntry[Idx].FileSelect);
Items.FwCfgItem[0].Size = SwapBytes32 (DirEntry[Idx].FileSize);
FetchStatus = QemuKernelFetchBlob (&Items);
Status = QemuKernelVerifyBlob (
(CHAR16 *)Items.Name,
FetchStatus
);
if (EFI_ERROR (Status)) {
FreePool (DirEntry);
return Status;
}
mKernelNamedBlobCount++;
}
FreePool (DirEntry);
return EFI_SUCCESS;
}
//
// The entry point of the feature.
//
/**
Download the kernel, the initial ramdisk, and the kernel command line from
QEMU's fw_cfg. Construct a minimal SimpleFileSystem that contains the two
image files.
@retval EFI_NOT_FOUND Kernel image was not found.
@retval EFI_OUT_OF_RESOURCES Memory allocation failed.
@retval EFI_PROTOCOL_ERROR Unterminated kernel command line.
@return Error codes from any of the underlying
functions. On success, the function doesn't
return.
**/
EFI_STATUS
EFIAPI
QemuKernelLoaderFsDxeEntrypoint (
IN EFI_HANDLE ImageHandle,
IN EFI_SYSTEM_TABLE *SystemTable
)
{
UINTN BlobIdx;
KERNEL_BLOB_ITEMS *BlobItems;
KERNEL_BLOB *Blob;
EFI_STATUS Status;
EFI_STATUS FetchStatus;
EFI_HANDLE FileSystemHandle;
EFI_HANDLE InitrdLoadFile2Handle;
if (!QemuFwCfgIsAvailable ()) {
return EFI_NOT_FOUND;
}
Status = gRT->GetTime (&mInitTime, NULL /* Capabilities */);
if (EFI_ERROR (Status)) {
DEBUG ((DEBUG_ERROR, "%a: GetTime(): %r\n", __func__, Status));
return Status;
}
//
// Fetch named blobs.
//
DEBUG ((DEBUG_INFO, "%a: named blobs (etc/boot/*)\n", __func__));
Status = QemuKernelFetchNamedBlobs ();
if (EFI_ERROR (Status)) {
goto FreeBlobs;
}
//
// Fetch traditional blobs.
//
DEBUG ((DEBUG_INFO, "%a: traditional blobs\n", __func__));
for (BlobIdx = 0; BlobIdx < ARRAY_SIZE (mKernelBlobItems); ++BlobIdx) {
BlobItems = &mKernelBlobItems[BlobIdx];
if (FindKernelBlob (BlobItems->Name)) {
continue;
}
FetchStatus = QemuKernelFetchBlob (BlobItems);
Status = QemuKernelVerifyBlob (
(CHAR16 *)BlobItems->Name,
FetchStatus
);
if (EFI_ERROR (Status)) {
goto FreeBlobs;
}
}
Blob = FindKernelBlob (L"kernel");
if ((Blob == NULL) && (mKernelNamedBlobCount == 0)) {
DEBUG ((DEBUG_INFO, "%a: no kernel and no named blobs present -> quit\n", __func__));
Status = EFI_NOT_FOUND;
goto FreeBlobs;
}
//
// Create a new handle with a single VenMedia() node device path protocol on
// it, plus a custom SimpleFileSystem protocol on it.
//
FileSystemHandle = NULL;
Status = gBS->InstallMultipleProtocolInterfaces (
&FileSystemHandle,
&gEfiDevicePathProtocolGuid,
&mFileSystemDevicePath,
&gEfiSimpleFileSystemProtocolGuid,
&mFileSystem,
NULL
);
if (EFI_ERROR (Status)) {
DEBUG ((
DEBUG_ERROR,
"%a: InstallMultipleProtocolInterfaces(): %r\n",
__func__,
Status
));
goto FreeBlobs;
}
Blob = FindKernelBlob (L"initrd");
if (Blob != NULL) {
DEBUG ((DEBUG_INFO, "%a: initrd setup\n", __func__));
InitrdLoadFile2Handle = NULL;
Status = gBS->InstallMultipleProtocolInterfaces (
&InitrdLoadFile2Handle,
&gEfiDevicePathProtocolGuid,
&mInitrdDevicePath,
&gEfiLoadFile2ProtocolGuid,
&mInitrdLoadFile2,
NULL
);
if (EFI_ERROR (Status)) {
DEBUG ((
DEBUG_ERROR,
"%a: InstallMultipleProtocolInterfaces(): %r\n",
__func__,
Status
));
goto UninstallFileSystemHandle;
}
}
return EFI_SUCCESS;
UninstallFileSystemHandle:
Status = gBS->UninstallMultipleProtocolInterfaces (
FileSystemHandle,
&gEfiDevicePathProtocolGuid,
&mFileSystemDevicePath,
&gEfiSimpleFileSystemProtocolGuid,
&mFileSystem,
NULL
);
ASSERT_EFI_ERROR (Status);
FreeBlobs:
while (mKernelBlobs != NULL) {
Blob = mKernelBlobs;
mKernelBlobs = Blob->Next;
FreePool (Blob->Data);
FreePool (Blob);
}
return Status;
}
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