/** @file
Section Extraction Protocol implementation.
Stream database is implemented as a linked list of section streams,
where each stream contains a linked list of children, which may be leaves or
encapsulations.
Children that are encapsulations generate new stream entries
when they are created. Streams can also be created by calls to
SEP->OpenSectionStream().
The database is only created far enough to return the requested data from
any given stream, or to determine that the requested data is not found.
If a GUIDed encapsulation is encountered, there are three possiblilites.
1) A support protocol is found, in which the stream is simply processed with
the support protocol.
2) A support protocol is not found, but the data is available to be read
without processing. In this case, the database is built up through the
recursions to return the data, and a RPN event is set that will enable
the stream in question to be refreshed if and when the required section
extraction protocol is published.This insures the AuthenticationStatus
does not become stale in the cache.
3) A support protocol is not found, and the data is not available to be read
without it. This results in EFI_PROTOCOL_ERROR.
Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
**/
#include "DxeMain.h"
//
// Local defines and typedefs
//
#define CORE_SECTION_CHILD_SIGNATURE SIGNATURE_32('S','X','C','S')
#define CHILD_SECTION_NODE_FROM_LINK(Node) \
CR (Node, CORE_SECTION_CHILD_NODE, Link, CORE_SECTION_CHILD_SIGNATURE)
typedef struct {
UINT32 Signature;
LIST_ENTRY Link;
UINT32 Type;
UINT32 Size;
//
// StreamBase + OffsetInStream == pointer to section header in stream. The
// stream base is always known when walking the sections within.
//
UINT32 OffsetInStream;
//
// Then EncapsulatedStreamHandle below is always 0 if the section is NOT an
// encapsulating section. Otherwise, it contains the stream handle
// of the encapsulated stream. This handle is ALWAYS produced any time an
// encapsulating child is encountered, irrespective of whether the
// encapsulated stream is processed further.
//
UINTN EncapsulatedStreamHandle;
EFI_GUID *EncapsulationGuid;
//
// If the section REQUIRES an extraction protocol, register for RPN
// when the required GUIDed extraction protocol becomes available.
//
EFI_EVENT Event;
} CORE_SECTION_CHILD_NODE;
#define CORE_SECTION_STREAM_SIGNATURE SIGNATURE_32('S','X','S','S')
#define STREAM_NODE_FROM_LINK(Node) \
CR (Node, CORE_SECTION_STREAM_NODE, Link, CORE_SECTION_STREAM_SIGNATURE)
typedef struct {
UINT32 Signature;
LIST_ENTRY Link;
UINTN StreamHandle;
UINT8 *StreamBuffer;
UINTN StreamLength;
LIST_ENTRY Children;
//
// Authentication status is from GUIDed encapsulations.
//
UINT32 AuthenticationStatus;
} CORE_SECTION_STREAM_NODE;
#define NULL_STREAM_HANDLE 0
typedef struct {
CORE_SECTION_CHILD_NODE *ChildNode;
CORE_SECTION_STREAM_NODE *ParentStream;
VOID *Registration;
} RPN_EVENT_CONTEXT;
/**
The ExtractSection() function processes the input section and
allocates a buffer from the pool in which it returns the section
contents. If the section being extracted contains
authentication information (the section's
GuidedSectionHeader.Attributes field has the
EFI_GUIDED_SECTION_AUTH_STATUS_VALID bit set), the values
returned in AuthenticationStatus must reflect the results of
the authentication operation. Depending on the algorithm and
size of the encapsulated data, the time that is required to do
a full authentication may be prohibitively long for some
classes of systems. To indicate this, use
EFI_SECURITY_POLICY_PROTOCOL_GUID, which may be published by
the security policy driver (see the Platform Initialization
Driver Execution Environment Core Interface Specification for
more details and the GUID definition). If the
EFI_SECURITY_POLICY_PROTOCOL_GUID exists in the handle
database, then, if possible, full authentication should be
skipped and the section contents simply returned in the
OutputBuffer. In this case, the
EFI_AUTH_STATUS_PLATFORM_OVERRIDE bit AuthenticationStatus
must be set on return. ExtractSection() is callable only from
TPL_NOTIFY and below. Behavior of ExtractSection() at any
EFI_TPL above TPL_NOTIFY is undefined. Type EFI_TPL is
defined in RaiseTPL() in the UEFI 2.0 specification.
@param This Indicates the
EFI_GUIDED_SECTION_EXTRACTION_PROTOCOL instance.
@param InputSection Buffer containing the input GUIDed section
to be processed. OutputBuffer OutputBuffer
is allocated from boot services pool
memory and contains the new section
stream. The caller is responsible for
freeing this buffer.
@param OutputBuffer *OutputBuffer is allocated from boot services
pool memory and contains the new section stream.
The caller is responsible for freeing this buffer.
@param OutputSize A pointer to a caller-allocated UINTN in
which the size of OutputBuffer allocation
is stored. If the function returns
anything other than EFI_SUCCESS, the value
of OutputSize is undefined.
@param AuthenticationStatus A pointer to a caller-allocated
UINT32 that indicates the
authentication status of the
output buffer. If the input
section's
GuidedSectionHeader.Attributes
field has the
EFI_GUIDED_SECTION_AUTH_STATUS_VAL
bit as clear, AuthenticationStatus
must return zero. Both local bits
(19:16) and aggregate bits (3:0)
in AuthenticationStatus are
returned by ExtractSection().
These bits reflect the status of
the extraction operation. The bit
pattern in both regions must be
the same, as the local and
aggregate authentication statuses
have equivalent meaning at this
level. If the function returns
anything other than EFI_SUCCESS,
the value of AuthenticationStatus
is undefined.
@retval EFI_SUCCESS The InputSection was successfully
processed and the section contents were
returned.
@retval EFI_OUT_OF_RESOURCES The system has insufficient
resources to process the
request.
@retval EFI_INVALID_PARAMETER The GUID in InputSection does
not match this instance of the
GUIDed Section Extraction
Protocol.
**/
EFI_STATUS
EFIAPI
CustomGuidedSectionExtract (
IN CONST EFI_GUIDED_SECTION_EXTRACTION_PROTOCOL *This,
IN CONST VOID *InputSection,
OUT VOID **OutputBuffer,
OUT UINTN *OutputSize,
OUT UINT32 *AuthenticationStatus
);
//
// Module globals
//
LIST_ENTRY mStreamRoot = INITIALIZE_LIST_HEAD_VARIABLE (mStreamRoot);
EFI_HANDLE mSectionExtractionHandle = NULL;
EFI_GUIDED_SECTION_EXTRACTION_PROTOCOL mCustomGuidedSectionExtractionProtocol = {
CustomGuidedSectionExtract
};
/**
Entry point of the section extraction code. Initializes an instance of the
section extraction interface and installs it on a new handle.
@param ImageHandle A handle for the image that is initializing this driver
@param SystemTable A pointer to the EFI system table
@retval EFI_SUCCESS Driver initialized successfully
@retval EFI_OUT_OF_RESOURCES Could not allocate needed resources
**/
EFI_STATUS
EFIAPI
InitializeSectionExtraction (
IN EFI_HANDLE ImageHandle,
IN EFI_SYSTEM_TABLE *SystemTable
)
{
EFI_STATUS Status;
EFI_GUID *ExtractHandlerGuidTable;
UINTN ExtractHandlerNumber;
//
// Get custom extract guided section method guid list
//
ExtractHandlerNumber = ExtractGuidedSectionGetGuidList (&ExtractHandlerGuidTable);
Status = EFI_SUCCESS;
//
// Install custom guided extraction protocol
//
while (ExtractHandlerNumber-- > 0) {
Status = CoreInstallProtocolInterface (
&mSectionExtractionHandle,
&ExtractHandlerGuidTable [ExtractHandlerNumber],
EFI_NATIVE_INTERFACE,
&mCustomGuidedSectionExtractionProtocol
);
ASSERT_EFI_ERROR (Status);
}
return Status;
}
/**
Check if a stream is valid.
@param SectionStream The section stream to be checked
@param SectionStreamLength The length of section stream
@return A boolean value indicating the validness of the section stream.
**/
BOOLEAN
IsValidSectionStream (
IN VOID *SectionStream,
IN UINTN SectionStreamLength
)
{
UINTN TotalLength;
UINTN SectionLength;
EFI_COMMON_SECTION_HEADER *SectionHeader;
EFI_COMMON_SECTION_HEADER *NextSectionHeader;
TotalLength = 0;
SectionHeader = (EFI_COMMON_SECTION_HEADER *)SectionStream;
while (TotalLength < SectionStreamLength) {
if (IS_SECTION2 (SectionHeader)) {
SectionLength = SECTION2_SIZE (SectionHeader);
} else {
SectionLength = SECTION_SIZE (SectionHeader);
}
TotalLength += SectionLength;
if (TotalLength == SectionStreamLength) {
return TRUE;
}
//
// Move to the next byte following the section...
//
SectionHeader = (EFI_COMMON_SECTION_HEADER *) ((UINT8 *) SectionHeader + SectionLength);
//
// Figure out where the next section begins
//
NextSectionHeader = ALIGN_POINTER(SectionHeader, 4);
TotalLength += (UINTN) NextSectionHeader - (UINTN) SectionHeader;
SectionHeader = NextSectionHeader;
}
ASSERT (FALSE);
return FALSE;
}
/**
Worker function. Constructor for section streams.
@param SectionStreamLength Size in bytes of the section stream.
@param SectionStream Buffer containing the new section stream.
@param AllocateBuffer Indicates whether the stream buffer is to be
copied or the input buffer is to be used in
place. AuthenticationStatus- Indicates the
default authentication status for the new
stream.
@param AuthenticationStatus A pointer to a caller-allocated UINT32 that
indicates the authentication status of the
output buffer. If the input section's
GuidedSectionHeader.Attributes field
has the EFI_GUIDED_SECTION_AUTH_STATUS_VALID
bit as clear, AuthenticationStatus must return
zero. Both local bits (19:16) and aggregate
bits (3:0) in AuthenticationStatus are returned
by ExtractSection(). These bits reflect the
status of the extraction operation. The bit
pattern in both regions must be the same, as
the local and aggregate authentication statuses
have equivalent meaning at this level. If the
function returns anything other than
EFI_SUCCESS, the value of *AuthenticationStatus
is undefined.
@param SectionStreamHandle A pointer to a caller allocated section stream
handle.
@retval EFI_SUCCESS Stream was added to stream database.
@retval EFI_OUT_OF_RESOURCES memory allocation failed.
**/
EFI_STATUS
OpenSectionStreamEx (
IN UINTN SectionStreamLength,
IN VOID *SectionStream,
IN BOOLEAN AllocateBuffer,
IN UINT32 AuthenticationStatus,
OUT UINTN *SectionStreamHandle
)
{
CORE_SECTION_STREAM_NODE *NewStream;
EFI_TPL OldTpl;
//
// Allocate a new stream
//
NewStream = AllocatePool (sizeof (CORE_SECTION_STREAM_NODE));
if (NewStream == NULL) {
return EFI_OUT_OF_RESOURCES;
}
if (AllocateBuffer) {
//
// if we're here, we're double buffering, allocate the buffer and copy the
// data in
//
if (SectionStreamLength > 0) {
NewStream->StreamBuffer = AllocatePool (SectionStreamLength);
if (NewStream->StreamBuffer == NULL) {
CoreFreePool (NewStream);
return EFI_OUT_OF_RESOURCES;
}
//
// Copy in stream data
//
CopyMem (NewStream->StreamBuffer, SectionStream, SectionStreamLength);
} else {
//
// It's possible to have a zero length section stream.
//
NewStream->StreamBuffer = NULL;
}
} else {
//
// If were here, the caller has supplied the buffer (it's an internal call)
// so just assign the buffer. This happens when we open section streams
// as a result of expanding an encapsulating section.
//
NewStream->StreamBuffer = SectionStream;
}
//
// Initialize the rest of the section stream
//
NewStream->Signature = CORE_SECTION_STREAM_SIGNATURE;
NewStream->StreamHandle = (UINTN) NewStream;
NewStream->StreamLength = SectionStreamLength;
InitializeListHead (&NewStream->Children);
NewStream->AuthenticationStatus = AuthenticationStatus;
//
// Add new stream to stream list
//
OldTpl = CoreRaiseTpl (TPL_NOTIFY);
InsertTailList (&mStreamRoot, &NewStream->Link);
CoreRestoreTpl (OldTpl);
*SectionStreamHandle = NewStream->StreamHandle;
return EFI_SUCCESS;
}
/**
SEP member function. This function creates and returns a new section stream
handle to represent the new section stream.
@param SectionStreamLength Size in bytes of the section stream.
@param SectionStream Buffer containing the new section stream.
@param SectionStreamHandle A pointer to a caller allocated UINTN that on
output contains the new section stream handle.
@retval EFI_SUCCESS The section stream is created successfully.
@retval EFI_OUT_OF_RESOURCES memory allocation failed.
@retval EFI_INVALID_PARAMETER Section stream does not end concident with end
of last section.
**/
EFI_STATUS
EFIAPI
OpenSectionStream (
IN UINTN SectionStreamLength,
IN VOID *SectionStream,
OUT UINTN *SectionStreamHandle
)
{
//
// Check to see section stream looks good...
//
if (!IsValidSectionStream (SectionStream, SectionStreamLength)) {
return EFI_INVALID_PARAMETER;
}
return OpenSectionStreamEx (
SectionStreamLength,
SectionStream,
FALSE,
0,
SectionStreamHandle
);
}
/**
Worker function. Determine if the input stream:child matches the input type.
@param Stream Indicates the section stream associated with the
child
@param Child Indicates the child to check
@param SearchType Indicates the type of section to check against
for
@param SectionDefinitionGuid Indicates the GUID to check against if the type
is EFI_SECTION_GUID_DEFINED
@retval TRUE The child matches
@retval FALSE The child doesn't match
**/
BOOLEAN
ChildIsType (
IN CORE_SECTION_STREAM_NODE *Stream,
IN CORE_SECTION_CHILD_NODE *Child,
IN EFI_SECTION_TYPE SearchType,
IN EFI_GUID *SectionDefinitionGuid
)
{
EFI_GUID_DEFINED_SECTION *GuidedSection;
if (SearchType == EFI_SECTION_ALL) {
return TRUE;
}
if (Child->Type != SearchType) {
return FALSE;
}
if ((SearchType != EFI_SECTION_GUID_DEFINED) || (SectionDefinitionGuid == NULL)) {
return TRUE;
}
GuidedSection = (EFI_GUID_DEFINED_SECTION * )(Stream->StreamBuffer + Child->OffsetInStream);
if (IS_SECTION2 (GuidedSection)) {
return CompareGuid (&(((EFI_GUID_DEFINED_SECTION2 *) GuidedSection)->SectionDefinitionGuid), SectionDefinitionGuid);
} else {
return CompareGuid (&GuidedSection->SectionDefinitionGuid, SectionDefinitionGuid);
}
}
/**
Verify the Guided Section GUID by checking if there is the Guided Section GUID configuration table recorded the GUID itself.
@param GuidedSectionGuid The Guided Section GUID.
@param GuidedSectionExtraction A pointer to the pointer to the supported Guided Section Extraction Protocol
for the Guided Section.
@return TRUE The GuidedSectionGuid could be identified, and the pointer to
the Guided Section Extraction Protocol will be returned to *GuidedSectionExtraction.
@return FALSE The GuidedSectionGuid could not be identified, or
the Guided Section Extraction Protocol has not been installed yet.
**/
BOOLEAN
VerifyGuidedSectionGuid (
IN EFI_GUID *GuidedSectionGuid,
OUT EFI_GUIDED_SECTION_EXTRACTION_PROTOCOL **GuidedSectionExtraction
)
{
EFI_GUID *GuidRecorded;
VOID *Interface;
EFI_STATUS Status;
Interface = NULL;
//
// Check if there is the Guided Section GUID configuration table recorded the GUID itself.
//
Status = EfiGetSystemConfigurationTable (GuidedSectionGuid, (VOID **) &GuidRecorded);
if (Status == EFI_SUCCESS) {
if (CompareGuid (GuidRecorded, GuidedSectionGuid)) {
//
// Found the recorded GuidedSectionGuid.
//
Status = CoreLocateProtocol (GuidedSectionGuid, NULL, (VOID **) &Interface);
if (!EFI_ERROR (Status) && Interface != NULL) {
//
// Found the supported Guided Section Extraction Porotocol for the Guided Section.
//
*GuidedSectionExtraction = (EFI_GUIDED_SECTION_EXTRACTION_PROTOCOL *) Interface;
return TRUE;
}
return FALSE;
}
}
return FALSE;
}
/**
RPN callback function. Initializes the section stream
when GUIDED_SECTION_EXTRACTION_PROTOCOL is installed.
@param Event The event that fired
@param RpnContext A pointer to the context that allows us to identify
the relevent encapsulation.
**/
VOID
EFIAPI
NotifyGuidedExtraction (
IN EFI_EVENT Event,
IN VOID *RpnContext
)
{
EFI_STATUS Status;
EFI_GUID_DEFINED_SECTION *GuidedHeader;
EFI_GUIDED_SECTION_EXTRACTION_PROTOCOL *GuidedExtraction;
VOID *NewStreamBuffer;
UINTN NewStreamBufferSize;
UINT32 AuthenticationStatus;
RPN_EVENT_CONTEXT *Context;
Context = RpnContext;
GuidedHeader = (EFI_GUID_DEFINED_SECTION *) (Context->ParentStream->StreamBuffer + Context->ChildNode->OffsetInStream);
ASSERT (GuidedHeader->CommonHeader.Type == EFI_SECTION_GUID_DEFINED);
if (!VerifyGuidedSectionGuid (Context->ChildNode->EncapsulationGuid, &GuidedExtraction)) {
return;
}
Status = GuidedExtraction->ExtractSection (
GuidedExtraction,
GuidedHeader,
&NewStreamBuffer,
&NewStreamBufferSize,
&AuthenticationStatus
);
ASSERT_EFI_ERROR (Status);
//
// Make sure we initialize the new stream with the correct
// authentication status for both aggregate and local status fields.
//
if ((GuidedHeader->Attributes & EFI_GUIDED_SECTION_AUTH_STATUS_VALID) != 0) {
//
// OR in the parent stream's aggregate status.
//
AuthenticationStatus |= Context->ParentStream->AuthenticationStatus & EFI_AUTH_STATUS_ALL;
} else {
//
// since there's no authentication data contributed by the section,
// just inherit the full value from our immediate parent.
//
AuthenticationStatus = Context->ParentStream->AuthenticationStatus;
}
Status = OpenSectionStreamEx (
NewStreamBufferSize,
NewStreamBuffer,
FALSE,
AuthenticationStatus,
&Context->ChildNode->EncapsulatedStreamHandle
);
ASSERT_EFI_ERROR (Status);
//
// Close the event when done.
//
gBS->CloseEvent (Event);
Context->ChildNode->Event = NULL;
FreePool (Context);
}
/**
Constructor for RPN event when a missing GUIDED_SECTION_EXTRACTION_PROTOCOL appears...
@param ParentStream Indicates the parent of the ecnapsulation section (child)
@param ChildNode Indicates the child node that is the encapsulation section.
**/
VOID
CreateGuidedExtractionRpnEvent (
IN CORE_SECTION_STREAM_NODE *ParentStream,
IN CORE_SECTION_CHILD_NODE *ChildNode
)
{
RPN_EVENT_CONTEXT *Context;
//
// Allocate new event structure and context
//
Context = AllocatePool (sizeof (RPN_EVENT_CONTEXT));
ASSERT (Context != NULL);
Context->ChildNode = ChildNode;
Context->ParentStream = ParentStream;
Context->ChildNode->Event = EfiCreateProtocolNotifyEvent (
Context->ChildNode->EncapsulationGuid,
TPL_NOTIFY,
NotifyGuidedExtraction,
Context,
&Context->Registration
);
}
/**
Worker function. Constructor for new child nodes.
@param Stream Indicates the section stream in which to add the
child.
@param ChildOffset Indicates the offset in Stream that is the
beginning of the child section.
@param ChildNode Indicates the Callee allocated and initialized
child.
@retval EFI_SUCCESS Child node was found and returned.
EFI_OUT_OF_RESOURCES- Memory allocation failed.
@retval EFI_PROTOCOL_ERROR Encapsulation sections produce new stream
handles when the child node is created. If the
section type is GUID defined, and the extraction
GUID does not exist, and producing the stream
requires the GUID, then a protocol error is
generated and no child is produced. Values
returned by OpenSectionStreamEx.
**/
EFI_STATUS
CreateChildNode (
IN CORE_SECTION_STREAM_NODE *Stream,
IN UINT32 ChildOffset,
OUT CORE_SECTION_CHILD_NODE **ChildNode
)
{
EFI_STATUS Status;
EFI_COMMON_SECTION_HEADER *SectionHeader;
EFI_COMPRESSION_SECTION *CompressionHeader;
EFI_GUID_DEFINED_SECTION *GuidedHeader;
EFI_DECOMPRESS_PROTOCOL *Decompress;
EFI_GUIDED_SECTION_EXTRACTION_PROTOCOL *GuidedExtraction;
VOID *NewStreamBuffer;
VOID *ScratchBuffer;
UINT32 ScratchSize;
UINTN NewStreamBufferSize;
UINT32 AuthenticationStatus;
VOID *CompressionSource;
UINT32 CompressionSourceSize;
UINT32 UncompressedLength;
UINT8 CompressionType;
UINT16 GuidedSectionAttributes;
CORE_SECTION_CHILD_NODE *Node;
SectionHeader = (EFI_COMMON_SECTION_HEADER *) (Stream->StreamBuffer + ChildOffset);
//
// Allocate a new node
//
*ChildNode = AllocateZeroPool (sizeof (CORE_SECTION_CHILD_NODE));
Node = *ChildNode;
if (Node == NULL) {
return EFI_OUT_OF_RESOURCES;
}
//
// Now initialize it
//
Node->Signature = CORE_SECTION_CHILD_SIGNATURE;
Node->Type = SectionHeader->Type;
if (IS_SECTION2 (SectionHeader)) {
Node->Size = SECTION2_SIZE (SectionHeader);
} else {
Node->Size = SECTION_SIZE (SectionHeader);
}
Node->OffsetInStream = ChildOffset;
Node->EncapsulatedStreamHandle = NULL_STREAM_HANDLE;
Node->EncapsulationGuid = NULL;
//
// If it's an encapsulating section, then create the new section stream also
//
switch (Node->Type) {
case EFI_SECTION_COMPRESSION:
//
// Get the CompressionSectionHeader
//
if (Node->Size < sizeof (EFI_COMPRESSION_SECTION)) {
CoreFreePool (Node);
return EFI_NOT_FOUND;
}
CompressionHeader = (EFI_COMPRESSION_SECTION *) SectionHeader;
if (IS_SECTION2 (CompressionHeader)) {
CompressionSource = (VOID *) ((UINT8 *) CompressionHeader + sizeof (EFI_COMPRESSION_SECTION2));
CompressionSourceSize = (UINT32) (SECTION2_SIZE (CompressionHeader) - sizeof (EFI_COMPRESSION_SECTION2));
UncompressedLength = ((EFI_COMPRESSION_SECTION2 *) CompressionHeader)->UncompressedLength;
CompressionType = ((EFI_COMPRESSION_SECTION2 *) CompressionHeader)->CompressionType;
} else {
CompressionSource = (VOID *) ((UINT8 *) CompressionHeader + sizeof (EFI_COMPRESSION_SECTION));
CompressionSourceSize = (UINT32) (SECTION_SIZE (CompressionHeader) - sizeof (EFI_COMPRESSION_SECTION));
UncompressedLength = CompressionHeader->UncompressedLength;
CompressionType = CompressionHeader->CompressionType;
}
//
// Allocate space for the new stream
//
if (UncompressedLength > 0) {
NewStreamBufferSize = UncompressedLength;
NewStreamBuffer = AllocatePool (NewStreamBufferSize);
if (NewStreamBuffer == NULL) {
CoreFreePool (Node);
return EFI_OUT_OF_RESOURCES;
}
if (CompressionType == EFI_NOT_COMPRESSED) {
//
// stream is not actually compressed, just encapsulated. So just copy it.
//
CopyMem (NewStreamBuffer, CompressionSource, NewStreamBufferSize);
} else if (CompressionType == EFI_STANDARD_COMPRESSION) {
//
// Only support the EFI_SATNDARD_COMPRESSION algorithm.
//
//
// Decompress the stream
//
Status = CoreLocateProtocol (&gEfiDecompressProtocolGuid, NULL, (VOID **)&Decompress);
ASSERT_EFI_ERROR (Status);
ASSERT (Decompress != NULL);
Status = Decompress->GetInfo (
Decompress,
CompressionSource,
CompressionSourceSize,
(UINT32 *)&NewStreamBufferSize,
&ScratchSize
);
if (EFI_ERROR (Status) || (NewStreamBufferSize != UncompressedLength)) {
CoreFreePool (Node);
CoreFreePool (NewStreamBuffer);
if (!EFI_ERROR (Status)) {
Status = EFI_BAD_BUFFER_SIZE;
}
return Status;
}
ScratchBuffer = AllocatePool (ScratchSize);
if (ScratchBuffer == NULL) {
CoreFreePool (Node);
CoreFreePool (NewStreamBuffer);
return EFI_OUT_OF_RESOURCES;
}
Status = Decompress->Decompress (
Decompress,
CompressionSource,
CompressionSourceSize,
NewStreamBuffer,
(UINT32)NewStreamBufferSize,
ScratchBuffer,
ScratchSize
);
CoreFreePool (ScratchBuffer);
if (EFI_ERROR (Status)) {
CoreFreePool (Node);
CoreFreePool (NewStreamBuffer);
return Status;
}
}
} else {
NewStreamBuffer = NULL;
NewStreamBufferSize = 0;
}
Status = OpenSectionStreamEx (
NewStreamBufferSize,
NewStreamBuffer,
FALSE,
Stream->AuthenticationStatus,
&Node->EncapsulatedStreamHandle
);
if (EFI_ERROR (Status)) {
CoreFreePool (Node);
CoreFreePool (NewStreamBuffer);
return Status;
}
break;
case EFI_SECTION_GUID_DEFINED:
GuidedHeader = (EFI_GUID_DEFINED_SECTION *) SectionHeader;
if (IS_SECTION2 (GuidedHeader)) {
Node->EncapsulationGuid = &(((EFI_GUID_DEFINED_SECTION2 *) GuidedHeader)->SectionDefinitionGuid);
GuidedSectionAttributes = ((EFI_GUID_DEFINED_SECTION2 *) GuidedHeader)->Attributes;
} else {
Node->EncapsulationGuid = &GuidedHeader->SectionDefinitionGuid;
GuidedSectionAttributes = GuidedHeader->Attributes;
}
if (VerifyGuidedSectionGuid (Node->EncapsulationGuid, &GuidedExtraction)) {
//
// NewStreamBuffer is always allocated by ExtractSection... No caller
// allocation here.
//
Status = GuidedExtraction->ExtractSection (
GuidedExtraction,
GuidedHeader,
&NewStreamBuffer,
&NewStreamBufferSize,
&AuthenticationStatus
);
if (EFI_ERROR (Status)) {
CoreFreePool (*ChildNode);
return EFI_PROTOCOL_ERROR;
}
//
// Make sure we initialize the new stream with the correct
// authentication status for both aggregate and local status fields.
//
if ((GuidedSectionAttributes & EFI_GUIDED_SECTION_AUTH_STATUS_VALID) != 0) {
//
// OR in the parent stream's aggregate status.
//
AuthenticationStatus |= Stream->AuthenticationStatus & EFI_AUTH_STATUS_ALL;
} else {
//
// since there's no authentication data contributed by the section,
// just inherit the full value from our immediate parent.
//
AuthenticationStatus = Stream->AuthenticationStatus;
}
Status = OpenSectionStreamEx (
NewStreamBufferSize,
NewStreamBuffer,
FALSE,
AuthenticationStatus,
&Node->EncapsulatedStreamHandle
);
if (EFI_ERROR (Status)) {
CoreFreePool (*ChildNode);
CoreFreePool (NewStreamBuffer);
return Status;
}
} else {
//
// There's no GUIDed section extraction protocol available.
//
if ((GuidedSectionAttributes & EFI_GUIDED_SECTION_PROCESSING_REQUIRED) != 0) {
//
// If the section REQUIRES an extraction protocol, register for RPN
// when the required GUIDed extraction protocol becomes available.
//
CreateGuidedExtractionRpnEvent (Stream, Node);
} else {
//
// Figure out the proper authentication status
//
AuthenticationStatus = Stream->AuthenticationStatus;
if ((GuidedSectionAttributes & EFI_GUIDED_SECTION_AUTH_STATUS_VALID) == EFI_GUIDED_SECTION_AUTH_STATUS_VALID) {
AuthenticationStatus |= EFI_AUTH_STATUS_IMAGE_SIGNED | EFI_AUTH_STATUS_NOT_TESTED;
}
if (IS_SECTION2 (GuidedHeader)) {
Status = OpenSectionStreamEx (
SECTION2_SIZE (GuidedHeader) - ((EFI_GUID_DEFINED_SECTION2 *) GuidedHeader)->DataOffset,
(UINT8 *) GuidedHeader + ((EFI_GUID_DEFINED_SECTION2 *) GuidedHeader)->DataOffset,
TRUE,
AuthenticationStatus,
&Node->EncapsulatedStreamHandle
);
} else {
Status = OpenSectionStreamEx (
SECTION_SIZE (GuidedHeader) - ((EFI_GUID_DEFINED_SECTION *) GuidedHeader)->DataOffset,
(UINT8 *) GuidedHeader + ((EFI_GUID_DEFINED_SECTION *) GuidedHeader)->DataOffset,
TRUE,
AuthenticationStatus,
&Node->EncapsulatedStreamHandle
);
}
if (EFI_ERROR (Status)) {
CoreFreePool (Node);
return Status;
}
}
}
break;
default:
//
// Nothing to do if it's a leaf
//
break;
}
//
// Last, add the new child node to the stream
//
InsertTailList (&Stream->Children, &Node->Link);
return EFI_SUCCESS;
}
/**
Worker function Recursively searches / builds section stream database
looking for requested section.
@param SourceStream Indicates the section stream in which to do the
search.
@param SearchType Indicates the type of section to search for.
@param SectionInstance Indicates which instance of section to find.
This is an in/out parameter to deal with
recursions.
@param SectionDefinitionGuid Guid of section definition
@param FoundChild Output indicating the child node that is found.
@param FoundStream Output indicating which section stream the child
was found in. If this stream was generated as a
result of an encapsulation section, the
streamhandle is visible within the SEP driver
only.
@param AuthenticationStatus Indicates the authentication status of the found section.
@retval EFI_SUCCESS Child node was found and returned.
EFI_OUT_OF_RESOURCES- Memory allocation failed.
@retval EFI_NOT_FOUND Requested child node does not exist.
@retval EFI_PROTOCOL_ERROR a required GUIDED section extraction protocol
does not exist
**/
EFI_STATUS
FindChildNode (
IN CORE_SECTION_STREAM_NODE *SourceStream,
IN EFI_SECTION_TYPE SearchType,
IN OUT UINTN *SectionInstance,
IN EFI_GUID *SectionDefinitionGuid,
OUT CORE_SECTION_CHILD_NODE **FoundChild,
OUT CORE_SECTION_STREAM_NODE **FoundStream,
OUT UINT32 *AuthenticationStatus
)
{
CORE_SECTION_CHILD_NODE *CurrentChildNode;
CORE_SECTION_CHILD_NODE *RecursedChildNode;
CORE_SECTION_STREAM_NODE *RecursedFoundStream;
UINT32 NextChildOffset;
EFI_STATUS ErrorStatus;
EFI_STATUS Status;
CurrentChildNode = NULL;
ErrorStatus = EFI_NOT_FOUND;
if (SourceStream->StreamLength == 0) {
return EFI_NOT_FOUND;
}
if (IsListEmpty (&SourceStream->Children) &&
SourceStream->StreamLength >= sizeof (EFI_COMMON_SECTION_HEADER)) {
//
// This occurs when a section stream exists, but no child sections
// have been parsed out yet. Therefore, extract the first child and add it
// to the list of children so we can get started.
// Section stream may contain an array of zero or more bytes.
// So, its size should be >= the size of commen section header.
//
Status = CreateChildNode (SourceStream, 0, &CurrentChildNode);
if (EFI_ERROR (Status)) {
return Status;
}
}
//
// At least one child has been parsed out of the section stream. So, walk
// through the sections that have already been parsed out looking for the
// requested section, if necessary, continue parsing section stream and
// adding children until either the requested section is found, or we run
// out of data
//
CurrentChildNode = CHILD_SECTION_NODE_FROM_LINK (GetFirstNode(&SourceStream->Children));
for (;;) {
ASSERT (CurrentChildNode != NULL);
if (ChildIsType (SourceStream, CurrentChildNode, SearchType, SectionDefinitionGuid)) {
//
// The type matches, so check the instance count to see if it's the one we want
//
(*SectionInstance)--;
if (*SectionInstance == 0) {
//
// Got it!
//
*FoundChild = CurrentChildNode;
*FoundStream = SourceStream;
*AuthenticationStatus = SourceStream->AuthenticationStatus;
return EFI_SUCCESS;
}
}
if (CurrentChildNode->EncapsulatedStreamHandle != NULL_STREAM_HANDLE) {
//
// If the current node is an encapsulating node, recurse into it...
//
Status = FindChildNode (
(CORE_SECTION_STREAM_NODE *)CurrentChildNode->EncapsulatedStreamHandle,
SearchType,
SectionInstance,
SectionDefinitionGuid,
&RecursedChildNode,
&RecursedFoundStream,
AuthenticationStatus
);
//
// If the status is not EFI_SUCCESS, just save the error code and continue
// to find the request child node in the rest stream.
//
if (*SectionInstance == 0) {
ASSERT_EFI_ERROR (Status);
*FoundChild = RecursedChildNode;
*FoundStream = RecursedFoundStream;
return EFI_SUCCESS;
} else {
ErrorStatus = Status;
}
} else if ((CurrentChildNode->Type == EFI_SECTION_GUID_DEFINED) && (SearchType != EFI_SECTION_GUID_DEFINED)) {
//
// When Node Type is GUIDED section, but Node has no encapsulated data, Node data should not be parsed
// because a required GUIDED section extraction protocol does not exist.
// If SearchType is not GUIDED section, EFI_PROTOCOL_ERROR should return.
//
ErrorStatus = EFI_PROTOCOL_ERROR;
}
if (!IsNodeAtEnd (&SourceStream->Children, &CurrentChildNode->Link)) {
//
// We haven't found the child node we're interested in yet, but there's
// still more nodes that have already been parsed so get the next one
// and continue searching..
//
CurrentChildNode = CHILD_SECTION_NODE_FROM_LINK (GetNextNode (&SourceStream->Children, &CurrentChildNode->Link));
} else {
//
// We've exhausted children that have already been parsed, so see if
// there's any more data and continue parsing out more children if there
// is.
//
NextChildOffset = CurrentChildNode->OffsetInStream + CurrentChildNode->Size;
//
// Round up to 4 byte boundary
//
NextChildOffset += 3;
NextChildOffset &= ~(UINTN) 3;
if (NextChildOffset <= SourceStream->StreamLength - sizeof (EFI_COMMON_SECTION_HEADER)) {
//
// There's an unparsed child remaining in the stream, so create a new child node
//
Status = CreateChildNode (SourceStream, NextChildOffset, &CurrentChildNode);
if (EFI_ERROR (Status)) {
return Status;
}
} else {
ASSERT (EFI_ERROR (ErrorStatus));
return ErrorStatus;
}
}
}
}
/**
Worker function. Search stream database for requested stream handle.
@param SearchHandle Indicates which stream to look for.
@param FoundStream Output pointer to the found stream.
@retval EFI_SUCCESS StreamHandle was found and *FoundStream contains
the stream node.
@retval EFI_NOT_FOUND SearchHandle was not found in the stream
database.
**/
EFI_STATUS
FindStreamNode (
IN UINTN SearchHandle,
OUT CORE_SECTION_STREAM_NODE **FoundStream
)
{
CORE_SECTION_STREAM_NODE *StreamNode;
if (!IsListEmpty (&mStreamRoot)) {
StreamNode = STREAM_NODE_FROM_LINK (GetFirstNode (&mStreamRoot));
for (;;) {
if (StreamNode->StreamHandle == SearchHandle) {
*FoundStream = StreamNode;
return EFI_SUCCESS;
} else if (IsNodeAtEnd (&mStreamRoot, &StreamNode->Link)) {
break;
} else {
StreamNode = STREAM_NODE_FROM_LINK (GetNextNode (&mStreamRoot, &StreamNode->Link));
}
}
}
return EFI_NOT_FOUND;
}
/**
SEP member function. Retrieves requested section from section stream.
@param SectionStreamHandle The section stream from which to extract the
requested section.
@param SectionType A pointer to the type of section to search for.
@param SectionDefinitionGuid If the section type is EFI_SECTION_GUID_DEFINED,
then SectionDefinitionGuid indicates which of
these types of sections to search for.
@param SectionInstance Indicates which instance of the requested
section to return.
@param Buffer Double indirection to buffer. If *Buffer is
non-null on input, then the buffer is caller
allocated. If Buffer is NULL, then the buffer
is callee allocated. In either case, the
required buffer size is returned in *BufferSize.
@param BufferSize On input, indicates the size of *Buffer if
*Buffer is non-null on input. On output,
indicates the required size (allocated size if
callee allocated) of *Buffer.
@param AuthenticationStatus A pointer to a caller-allocated UINT32 that
indicates the authentication status of the
output buffer. If the input section's
GuidedSectionHeader.Attributes field
has the EFI_GUIDED_SECTION_AUTH_STATUS_VALID
bit as clear, AuthenticationStatus must return
zero. Both local bits (19:16) and aggregate
bits (3:0) in AuthenticationStatus are returned
by ExtractSection(). These bits reflect the
status of the extraction operation. The bit
pattern in both regions must be the same, as
the local and aggregate authentication statuses
have equivalent meaning at this level. If the
function returns anything other than
EFI_SUCCESS, the value of *AuthenticationStatus
is undefined.
@param IsFfs3Fv Indicates the FV format.
@retval EFI_SUCCESS Section was retrieved successfully
@retval EFI_PROTOCOL_ERROR A GUID defined section was encountered in the
section stream with its
EFI_GUIDED_SECTION_PROCESSING_REQUIRED bit set,
but there was no corresponding GUIDed Section
Extraction Protocol in the handle database.
*Buffer is unmodified.
@retval EFI_NOT_FOUND An error was encountered when parsing the
SectionStream. This indicates the SectionStream
is not correctly formatted.
@retval EFI_NOT_FOUND The requested section does not exist.
@retval EFI_OUT_OF_RESOURCES The system has insufficient resources to process
the request.
@retval EFI_INVALID_PARAMETER The SectionStreamHandle does not exist.
@retval EFI_WARN_TOO_SMALL The size of the caller allocated input buffer is
insufficient to contain the requested section.
The input buffer is filled and section contents
are truncated.
**/
EFI_STATUS
EFIAPI
GetSection (
IN UINTN SectionStreamHandle,
IN EFI_SECTION_TYPE *SectionType,
IN EFI_GUID *SectionDefinitionGuid,
IN UINTN SectionInstance,
IN VOID **Buffer,
IN OUT UINTN *BufferSize,
OUT UINT32 *AuthenticationStatus,
IN BOOLEAN IsFfs3Fv
)
{
CORE_SECTION_STREAM_NODE *StreamNode;
EFI_TPL OldTpl;
EFI_STATUS Status;
CORE_SECTION_CHILD_NODE *ChildNode;
CORE_SECTION_STREAM_NODE *ChildStreamNode;
UINTN CopySize;
UINT32 ExtractedAuthenticationStatus;
UINTN Instance;
UINT8 *CopyBuffer;
UINTN SectionSize;
EFI_COMMON_SECTION_HEADER *Section;
ChildStreamNode = NULL;
OldTpl = CoreRaiseTpl (TPL_NOTIFY);
Instance = SectionInstance + 1;
//
// Locate target stream
//
Status = FindStreamNode (SectionStreamHandle, &StreamNode);
if (EFI_ERROR (Status)) {
Status = EFI_INVALID_PARAMETER;
goto GetSection_Done;
}
//
// Found the stream, now locate and return the appropriate section
//
if (SectionType == NULL) {
//
// SectionType == NULL means return the WHOLE section stream...
//
CopySize = StreamNode->StreamLength;
CopyBuffer = StreamNode->StreamBuffer;
*AuthenticationStatus = StreamNode->AuthenticationStatus;
} else {
//
// There's a requested section type, so go find it and return it...
//
Status = FindChildNode (
StreamNode,
*SectionType,
&Instance,
SectionDefinitionGuid,
&ChildNode,
&ChildStreamNode,
&ExtractedAuthenticationStatus
);
if (EFI_ERROR (Status)) {
goto GetSection_Done;
}
Section = (EFI_COMMON_SECTION_HEADER *) (ChildStreamNode->StreamBuffer + ChildNode->OffsetInStream);
if (IS_SECTION2 (Section)) {
ASSERT (SECTION2_SIZE (Section) > 0x00FFFFFF);
if (!IsFfs3Fv) {
DEBUG ((DEBUG_ERROR, "It is a FFS3 formatted section in a non-FFS3 formatted FV.\n"));
Status = EFI_NOT_FOUND;
goto GetSection_Done;
}
CopySize = SECTION2_SIZE (Section) - sizeof (EFI_COMMON_SECTION_HEADER2);
CopyBuffer = (UINT8 *) Section + sizeof (EFI_COMMON_SECTION_HEADER2);
} else {
CopySize = SECTION_SIZE (Section) - sizeof (EFI_COMMON_SECTION_HEADER);
CopyBuffer = (UINT8 *) Section + sizeof (EFI_COMMON_SECTION_HEADER);
}
*AuthenticationStatus = ExtractedAuthenticationStatus;
}
SectionSize = CopySize;
if (*Buffer != NULL) {
//
// Caller allocated buffer. Fill to size and return required size...
//
if (*BufferSize < CopySize) {
Status = EFI_WARN_BUFFER_TOO_SMALL;
CopySize = *BufferSize;
}
} else {
//
// Callee allocated buffer. Allocate buffer and return size.
//
*Buffer = AllocatePool (CopySize);
if (*Buffer == NULL) {
Status = EFI_OUT_OF_RESOURCES;
goto GetSection_Done;
}
}
CopyMem (*Buffer, CopyBuffer, CopySize);
*BufferSize = SectionSize;
GetSection_Done:
CoreRestoreTpl (OldTpl);
return Status;
}
/**
Worker function. Destructor for child nodes.
@param ChildNode Indicates the node to destroy
**/
VOID
FreeChildNode (
IN CORE_SECTION_CHILD_NODE *ChildNode
)
{
ASSERT (ChildNode->Signature == CORE_SECTION_CHILD_SIGNATURE);
//
// Remove the child from it's list
//
RemoveEntryList (&ChildNode->Link);
if (ChildNode->EncapsulatedStreamHandle != NULL_STREAM_HANDLE) {
//
// If it's an encapsulating section, we close the resulting section stream.
// CloseSectionStream will free all memory associated with the stream.
//
CloseSectionStream (ChildNode->EncapsulatedStreamHandle, TRUE);
}
if (ChildNode->Event != NULL) {
gBS->CloseEvent (ChildNode->Event);
}
//
// Last, free the child node itself
//
CoreFreePool (ChildNode);
}
/**
SEP member function. Deletes an existing section stream
@param StreamHandleToClose Indicates the stream to close
@param FreeStreamBuffer TRUE - Need to free stream buffer;
FALSE - No need to free stream buffer.
@retval EFI_SUCCESS The section stream is closed sucessfully.
@retval EFI_OUT_OF_RESOURCES Memory allocation failed.
@retval EFI_INVALID_PARAMETER Section stream does not end concident with end
of last section.
**/
EFI_STATUS
EFIAPI
CloseSectionStream (
IN UINTN StreamHandleToClose,
IN BOOLEAN FreeStreamBuffer
)
{
CORE_SECTION_STREAM_NODE *StreamNode;
EFI_TPL OldTpl;
EFI_STATUS Status;
LIST_ENTRY *Link;
CORE_SECTION_CHILD_NODE *ChildNode;
OldTpl = CoreRaiseTpl (TPL_NOTIFY);
//
// Locate target stream
//
Status = FindStreamNode (StreamHandleToClose, &StreamNode);
if (!EFI_ERROR (Status)) {
//
// Found the stream, so close it
//
RemoveEntryList (&StreamNode->Link);
while (!IsListEmpty (&StreamNode->Children)) {
Link = GetFirstNode (&StreamNode->Children);
ChildNode = CHILD_SECTION_NODE_FROM_LINK (Link);
FreeChildNode (ChildNode);
}
if (FreeStreamBuffer) {
CoreFreePool (StreamNode->StreamBuffer);
}
CoreFreePool (StreamNode);
Status = EFI_SUCCESS;
} else {
Status = EFI_INVALID_PARAMETER;
}
CoreRestoreTpl (OldTpl);
return Status;
}
/**
The ExtractSection() function processes the input section and
allocates a buffer from the pool in which it returns the section
contents. If the section being extracted contains
authentication information (the section's
GuidedSectionHeader.Attributes field has the
EFI_GUIDED_SECTION_AUTH_STATUS_VALID bit set), the values
returned in AuthenticationStatus must reflect the results of
the authentication operation. Depending on the algorithm and
size of the encapsulated data, the time that is required to do
a full authentication may be prohibitively long for some
classes of systems. To indicate this, use
EFI_SECURITY_POLICY_PROTOCOL_GUID, which may be published by
the security policy driver (see the Platform Initialization
Driver Execution Environment Core Interface Specification for
more details and the GUID definition). If the
EFI_SECURITY_POLICY_PROTOCOL_GUID exists in the handle
database, then, if possible, full authentication should be
skipped and the section contents simply returned in the
OutputBuffer. In this case, the
EFI_AUTH_STATUS_PLATFORM_OVERRIDE bit AuthenticationStatus
must be set on return. ExtractSection() is callable only from
TPL_NOTIFY and below. Behavior of ExtractSection() at any
EFI_TPL above TPL_NOTIFY is undefined. Type EFI_TPL is
defined in RaiseTPL() in the UEFI 2.0 specification.
@param This Indicates the
EFI_GUIDED_SECTION_EXTRACTION_PROTOCOL instance.
@param InputSection Buffer containing the input GUIDed section
to be processed. OutputBuffer OutputBuffer
is allocated from boot services pool
memory and contains the new section
stream. The caller is responsible for
freeing this buffer.
@param OutputBuffer *OutputBuffer is allocated from boot services
pool memory and contains the new section stream.
The caller is responsible for freeing this buffer.
@param OutputSize A pointer to a caller-allocated UINTN in
which the size of OutputBuffer allocation
is stored. If the function returns
anything other than EFI_SUCCESS, the value
of OutputSize is undefined.
@param AuthenticationStatus A pointer to a caller-allocated
UINT32 that indicates the
authentication status of the
output buffer. If the input
section's
GuidedSectionHeader.Attributes
field has the
EFI_GUIDED_SECTION_AUTH_STATUS_VAL
bit as clear, AuthenticationStatus
must return zero. Both local bits
(19:16) and aggregate bits (3:0)
in AuthenticationStatus are
returned by ExtractSection().
These bits reflect the status of
the extraction operation. The bit
pattern in both regions must be
the same, as the local and
aggregate authentication statuses
have equivalent meaning at this
level. If the function returns
anything other than EFI_SUCCESS,
the value of AuthenticationStatus
is undefined.
@retval EFI_SUCCESS The InputSection was successfully
processed and the section contents were
returned.
@retval EFI_OUT_OF_RESOURCES The system has insufficient
resources to process the
request.
@retval EFI_INVALID_PARAMETER The GUID in InputSection does
not match this instance of the
GUIDed Section Extraction
Protocol.
**/
EFI_STATUS
EFIAPI
CustomGuidedSectionExtract (
IN CONST EFI_GUIDED_SECTION_EXTRACTION_PROTOCOL *This,
IN CONST VOID *InputSection,
OUT VOID **OutputBuffer,
OUT UINTN *OutputSize,
OUT UINT32 *AuthenticationStatus
)
{
EFI_STATUS Status;
VOID *ScratchBuffer;
VOID *AllocatedOutputBuffer;
UINT32 OutputBufferSize;
UINT32 ScratchBufferSize;
UINT16 SectionAttribute;
//
// Init local variable
//
ScratchBuffer = NULL;
AllocatedOutputBuffer = NULL;
//
// Call GetInfo to get the size and attribute of input guided section data.
//
Status = ExtractGuidedSectionGetInfo (
InputSection,
&OutputBufferSize,
&ScratchBufferSize,
&SectionAttribute
);
if (EFI_ERROR (Status)) {
DEBUG ((DEBUG_ERROR, "GetInfo from guided section Failed - %r\n", Status));
return Status;
}
if (ScratchBufferSize > 0) {
//
// Allocate scratch buffer
//
ScratchBuffer = AllocatePool (ScratchBufferSize);
if (ScratchBuffer == NULL) {
return EFI_OUT_OF_RESOURCES;
}
}
if (OutputBufferSize > 0) {
//
// Allocate output buffer
//
AllocatedOutputBuffer = AllocatePool (OutputBufferSize);
if (AllocatedOutputBuffer == NULL) {
FreePool (ScratchBuffer);
return EFI_OUT_OF_RESOURCES;
}
*OutputBuffer = AllocatedOutputBuffer;
}
//
// Call decode function to extract raw data from the guided section.
//
Status = ExtractGuidedSectionDecode (
InputSection,
OutputBuffer,
ScratchBuffer,
AuthenticationStatus
);
if (EFI_ERROR (Status)) {
//
// Decode failed
//
if (AllocatedOutputBuffer != NULL) {
CoreFreePool (AllocatedOutputBuffer);
}
if (ScratchBuffer != NULL) {
CoreFreePool (ScratchBuffer);
}
DEBUG ((DEBUG_ERROR, "Extract guided section Failed - %r\n", Status));
return Status;
}
if (*OutputBuffer != AllocatedOutputBuffer) {
//
// OutputBuffer was returned as a different value,
// so copy section contents to the allocated memory buffer.
//
CopyMem (AllocatedOutputBuffer, *OutputBuffer, OutputBufferSize);
*OutputBuffer = AllocatedOutputBuffer;
}
//
// Set real size of output buffer.
//
*OutputSize = (UINTN) OutputBufferSize;
//
// Free unused scratch buffer.
//
if (ScratchBuffer != NULL) {
CoreFreePool (ScratchBuffer);
}
return EFI_SUCCESS;
}