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DxeImageVerificationLib.c
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DxeImageVerificationLib.c
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/** @file
Implement image verification services for secure boot service
Caution: This file requires additional review when modified.
This library will have external input - PE/COFF image.
This external input must be validated carefully to avoid security issue like
buffer overflow, integer overflow.
DxeImageVerificationLibImageRead() function will make sure the PE/COFF image content
read is within the image buffer.
DxeImageVerificationHandler(), HashPeImageByType(), HashPeImage() function will accept
untrusted PE/COFF image and validate its data structure within this image buffer before use.
Copyright (c) 2009 - 2018, Intel Corporation. All rights reserved.<BR>
(C) Copyright 2016 Hewlett Packard Enterprise Development LP<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include "DxeImageVerificationLib.h"
//
// Caution: This is used by a function which may receive untrusted input.
// These global variables hold PE/COFF image data, and they should be validated before use.
//
EFI_IMAGE_OPTIONAL_HEADER_PTR_UNION mNtHeader;
UINT32 mPeCoffHeaderOffset;
EFI_GUID mCertType;
//
// Information on current PE/COFF image
//
UINTN mImageSize;
UINT8 *mImageBase = NULL;
UINT8 mImageDigest[MAX_DIGEST_SIZE];
UINTN mImageDigestSize;
//
// Notify string for authorization UI.
//
CHAR16 mNotifyString1[MAX_NOTIFY_STRING_LEN] = L"Image verification pass but not found in authorized database!";
CHAR16 mNotifyString2[MAX_NOTIFY_STRING_LEN] = L"Launch this image anyway? (Yes/Defer/No)";
//
// Public Exponent of RSA Key.
//
CONST UINT8 mRsaE[] = { 0x01, 0x00, 0x01 };
//
// OID ASN.1 Value for Hash Algorithms
//
UINT8 mHashOidValue[] = {
0x2B, 0x0E, 0x03, 0x02, 0x1A, // OBJ_sha1
0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04, // OBJ_sha224
0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, // OBJ_sha256
0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02, // OBJ_sha384
0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, // OBJ_sha512
};
HASH_TABLE mHash[] = {
{ L"SHA1", 20, &mHashOidValue[0], 5, Sha1GetContextSize, Sha1Init, Sha1Update, Sha1Final },
{ L"SHA224", 28, &mHashOidValue[5], 9, NULL, NULL, NULL, NULL },
{ L"SHA256", 32, &mHashOidValue[14], 9, Sha256GetContextSize, Sha256Init, Sha256Update, Sha256Final},
{ L"SHA384", 48, &mHashOidValue[23], 9, Sha384GetContextSize, Sha384Init, Sha384Update, Sha384Final},
{ L"SHA512", 64, &mHashOidValue[32], 9, Sha512GetContextSize, Sha512Init, Sha512Update, Sha512Final}
};
EFI_STRING mHashTypeStr;
/**
SecureBoot Hook for processing image verification.
@param[in] VariableName Name of Variable to be found.
@param[in] VendorGuid Variable vendor GUID.
@param[in] DataSize Size of Data found. If size is less than the
data, this value contains the required size.
@param[in] Data Data pointer.
**/
VOID
EFIAPI
SecureBootHook (
IN CHAR16 *VariableName,
IN EFI_GUID *VendorGuid,
IN UINTN DataSize,
IN VOID *Data
);
/**
Reads contents of a PE/COFF image in memory buffer.
Caution: This function may receive untrusted input.
PE/COFF image is external input, so this function will make sure the PE/COFF image content
read is within the image buffer.
@param FileHandle Pointer to the file handle to read the PE/COFF image.
@param FileOffset Offset into the PE/COFF image to begin the read operation.
@param ReadSize On input, the size in bytes of the requested read operation.
On output, the number of bytes actually read.
@param Buffer Output buffer that contains the data read from the PE/COFF image.
@retval EFI_SUCCESS The specified portion of the PE/COFF image was read and the size
**/
EFI_STATUS
EFIAPI
DxeImageVerificationLibImageRead (
IN VOID *FileHandle,
IN UINTN FileOffset,
IN OUT UINTN *ReadSize,
OUT VOID *Buffer
)
{
UINTN EndPosition;
if (FileHandle == NULL || ReadSize == NULL || Buffer == NULL) {
return EFI_INVALID_PARAMETER;
}
if (MAX_ADDRESS - FileOffset < *ReadSize) {
return EFI_INVALID_PARAMETER;
}
EndPosition = FileOffset + *ReadSize;
if (EndPosition > mImageSize) {
*ReadSize = (UINT32)(mImageSize - FileOffset);
}
if (FileOffset >= mImageSize) {
*ReadSize = 0;
}
CopyMem (Buffer, (UINT8 *)((UINTN) FileHandle + FileOffset), *ReadSize);
return EFI_SUCCESS;
}
/**
Get the image type.
@param[in] File This is a pointer to the device path of the file that is
being dispatched.
@return UINT32 Image Type
**/
UINT32
GetImageType (
IN CONST EFI_DEVICE_PATH_PROTOCOL *File
)
{
EFI_STATUS Status;
EFI_HANDLE DeviceHandle;
EFI_DEVICE_PATH_PROTOCOL *TempDevicePath;
EFI_BLOCK_IO_PROTOCOL *BlockIo;
if (File == NULL) {
return IMAGE_UNKNOWN;
}
//
// First check to see if File is from a Firmware Volume
//
DeviceHandle = NULL;
TempDevicePath = (EFI_DEVICE_PATH_PROTOCOL *) File;
Status = gBS->LocateDevicePath (
&gEfiFirmwareVolume2ProtocolGuid,
&TempDevicePath,
&DeviceHandle
);
if (!EFI_ERROR (Status)) {
Status = gBS->OpenProtocol (
DeviceHandle,
&gEfiFirmwareVolume2ProtocolGuid,
NULL,
NULL,
NULL,
EFI_OPEN_PROTOCOL_TEST_PROTOCOL
);
if (!EFI_ERROR (Status)) {
return IMAGE_FROM_FV;
}
}
//
// Next check to see if File is from a Block I/O device
//
DeviceHandle = NULL;
TempDevicePath = (EFI_DEVICE_PATH_PROTOCOL *) File;
Status = gBS->LocateDevicePath (
&gEfiBlockIoProtocolGuid,
&TempDevicePath,
&DeviceHandle
);
if (!EFI_ERROR (Status)) {
BlockIo = NULL;
Status = gBS->OpenProtocol (
DeviceHandle,
&gEfiBlockIoProtocolGuid,
(VOID **) &BlockIo,
NULL,
NULL,
EFI_OPEN_PROTOCOL_GET_PROTOCOL
);
if (!EFI_ERROR (Status) && BlockIo != NULL) {
if (BlockIo->Media != NULL) {
if (BlockIo->Media->RemovableMedia) {
//
// Block I/O is present and specifies the media is removable
//
return IMAGE_FROM_REMOVABLE_MEDIA;
} else {
//
// Block I/O is present and specifies the media is not removable
//
return IMAGE_FROM_FIXED_MEDIA;
}
}
}
}
//
// File is not in a Firmware Volume or on a Block I/O device, so check to see if
// the device path supports the Simple File System Protocol.
//
DeviceHandle = NULL;
TempDevicePath = (EFI_DEVICE_PATH_PROTOCOL *) File;
Status = gBS->LocateDevicePath (
&gEfiSimpleFileSystemProtocolGuid,
&TempDevicePath,
&DeviceHandle
);
if (!EFI_ERROR (Status)) {
//
// Simple File System is present without Block I/O, so assume media is fixed.
//
return IMAGE_FROM_FIXED_MEDIA;
}
//
// File is not from an FV, Block I/O or Simple File System, so the only options
// left are a PCI Option ROM and a Load File Protocol such as a PXE Boot from a NIC.
//
TempDevicePath = (EFI_DEVICE_PATH_PROTOCOL *) File;
while (!IsDevicePathEndType (TempDevicePath)) {
switch (DevicePathType (TempDevicePath)) {
case MEDIA_DEVICE_PATH:
if (DevicePathSubType (TempDevicePath) == MEDIA_RELATIVE_OFFSET_RANGE_DP) {
return IMAGE_FROM_OPTION_ROM;
}
break;
case MESSAGING_DEVICE_PATH:
if (DevicePathSubType(TempDevicePath) == MSG_MAC_ADDR_DP) {
return IMAGE_FROM_REMOVABLE_MEDIA;
}
break;
default:
break;
}
TempDevicePath = NextDevicePathNode (TempDevicePath);
}
return IMAGE_UNKNOWN;
}
/**
Calculate hash of Pe/Coff image based on the authenticode image hashing in
PE/COFF Specification 8.0 Appendix A
Caution: This function may receive untrusted input.
PE/COFF image is external input, so this function will validate its data structure
within this image buffer before use.
Notes: PE/COFF image has been checked by BasePeCoffLib PeCoffLoaderGetImageInfo() in
its caller function DxeImageVerificationHandler().
@param[in] HashAlg Hash algorithm type.
@retval TRUE Successfully hash image.
@retval FALSE Fail in hash image.
**/
BOOLEAN
HashPeImage (
IN UINT32 HashAlg
)
{
BOOLEAN Status;
EFI_IMAGE_SECTION_HEADER *Section;
VOID *HashCtx;
UINTN CtxSize;
UINT8 *HashBase;
UINTN HashSize;
UINTN SumOfBytesHashed;
EFI_IMAGE_SECTION_HEADER *SectionHeader;
UINTN Index;
UINTN Pos;
UINT32 CertSize;
UINT32 NumberOfRvaAndSizes;
HashCtx = NULL;
SectionHeader = NULL;
Status = FALSE;
if ((HashAlg >= HASHALG_MAX)) {
return FALSE;
}
//
// Initialize context of hash.
//
ZeroMem (mImageDigest, MAX_DIGEST_SIZE);
switch (HashAlg) {
case HASHALG_SHA1:
mImageDigestSize = SHA1_DIGEST_SIZE;
mCertType = gEfiCertSha1Guid;
break;
case HASHALG_SHA256:
mImageDigestSize = SHA256_DIGEST_SIZE;
mCertType = gEfiCertSha256Guid;
break;
case HASHALG_SHA384:
mImageDigestSize = SHA384_DIGEST_SIZE;
mCertType = gEfiCertSha384Guid;
break;
case HASHALG_SHA512:
mImageDigestSize = SHA512_DIGEST_SIZE;
mCertType = gEfiCertSha512Guid;
break;
default:
return FALSE;
}
mHashTypeStr = mHash[HashAlg].Name;
CtxSize = mHash[HashAlg].GetContextSize();
HashCtx = AllocatePool (CtxSize);
if (HashCtx == NULL) {
return FALSE;
}
// 1. Load the image header into memory.
// 2. Initialize a SHA hash context.
Status = mHash[HashAlg].HashInit(HashCtx);
if (!Status) {
goto Done;
}
//
// Measuring PE/COFF Image Header;
// But CheckSum field and SECURITY data directory (certificate) are excluded
//
//
// 3. Calculate the distance from the base of the image header to the image checksum address.
// 4. Hash the image header from its base to beginning of the image checksum.
//
HashBase = mImageBase;
if (mNtHeader.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
HashSize = (UINTN) (&mNtHeader.Pe32->OptionalHeader.CheckSum) - (UINTN) HashBase;
NumberOfRvaAndSizes = mNtHeader.Pe32->OptionalHeader.NumberOfRvaAndSizes;
} else if (mNtHeader.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC) {
//
// Use PE32+ offset.
//
HashSize = (UINTN) (&mNtHeader.Pe32Plus->OptionalHeader.CheckSum) - (UINTN) HashBase;
NumberOfRvaAndSizes = mNtHeader.Pe32Plus->OptionalHeader.NumberOfRvaAndSizes;
} else {
//
// Invalid header magic number.
//
Status = FALSE;
goto Done;
}
Status = mHash[HashAlg].HashUpdate(HashCtx, HashBase, HashSize);
if (!Status) {
goto Done;
}
//
// 5. Skip over the image checksum (it occupies a single ULONG).
//
if (NumberOfRvaAndSizes <= EFI_IMAGE_DIRECTORY_ENTRY_SECURITY) {
//
// 6. Since there is no Cert Directory in optional header, hash everything
// from the end of the checksum to the end of image header.
//
if (mNtHeader.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
HashBase = (UINT8 *) &mNtHeader.Pe32->OptionalHeader.CheckSum + sizeof (UINT32);
HashSize = mNtHeader.Pe32->OptionalHeader.SizeOfHeaders - ((UINTN) HashBase - (UINTN) mImageBase);
} else {
//
// Use PE32+ offset.
//
HashBase = (UINT8 *) &mNtHeader.Pe32Plus->OptionalHeader.CheckSum + sizeof (UINT32);
HashSize = mNtHeader.Pe32Plus->OptionalHeader.SizeOfHeaders - ((UINTN) HashBase - (UINTN) mImageBase);
}
if (HashSize != 0) {
Status = mHash[HashAlg].HashUpdate(HashCtx, HashBase, HashSize);
if (!Status) {
goto Done;
}
}
} else {
//
// 7. Hash everything from the end of the checksum to the start of the Cert Directory.
//
if (mNtHeader.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
HashBase = (UINT8 *) &mNtHeader.Pe32->OptionalHeader.CheckSum + sizeof (UINT32);
HashSize = (UINTN) (&mNtHeader.Pe32->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY]) - (UINTN) HashBase;
} else {
//
// Use PE32+ offset.
//
HashBase = (UINT8 *) &mNtHeader.Pe32Plus->OptionalHeader.CheckSum + sizeof (UINT32);
HashSize = (UINTN) (&mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY]) - (UINTN) HashBase;
}
if (HashSize != 0) {
Status = mHash[HashAlg].HashUpdate(HashCtx, HashBase, HashSize);
if (!Status) {
goto Done;
}
}
//
// 8. Skip over the Cert Directory. (It is sizeof(IMAGE_DATA_DIRECTORY) bytes.)
// 9. Hash everything from the end of the Cert Directory to the end of image header.
//
if (mNtHeader.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset
//
HashBase = (UINT8 *) &mNtHeader.Pe32->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY + 1];
HashSize = mNtHeader.Pe32->OptionalHeader.SizeOfHeaders - ((UINTN) HashBase - (UINTN) mImageBase);
} else {
//
// Use PE32+ offset.
//
HashBase = (UINT8 *) &mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY + 1];
HashSize = mNtHeader.Pe32Plus->OptionalHeader.SizeOfHeaders - ((UINTN) HashBase - (UINTN) mImageBase);
}
if (HashSize != 0) {
Status = mHash[HashAlg].HashUpdate(HashCtx, HashBase, HashSize);
if (!Status) {
goto Done;
}
}
}
//
// 10. Set the SUM_OF_BYTES_HASHED to the size of the header.
//
if (mNtHeader.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
SumOfBytesHashed = mNtHeader.Pe32->OptionalHeader.SizeOfHeaders;
} else {
//
// Use PE32+ offset
//
SumOfBytesHashed = mNtHeader.Pe32Plus->OptionalHeader.SizeOfHeaders;
}
Section = (EFI_IMAGE_SECTION_HEADER *) (
mImageBase +
mPeCoffHeaderOffset +
sizeof (UINT32) +
sizeof (EFI_IMAGE_FILE_HEADER) +
mNtHeader.Pe32->FileHeader.SizeOfOptionalHeader
);
//
// 11. Build a temporary table of pointers to all the IMAGE_SECTION_HEADER
// structures in the image. The 'NumberOfSections' field of the image
// header indicates how big the table should be. Do not include any
// IMAGE_SECTION_HEADERs in the table whose 'SizeOfRawData' field is zero.
//
SectionHeader = (EFI_IMAGE_SECTION_HEADER *) AllocateZeroPool (sizeof (EFI_IMAGE_SECTION_HEADER) * mNtHeader.Pe32->FileHeader.NumberOfSections);
if (SectionHeader == NULL) {
Status = FALSE;
goto Done;
}
//
// 12. Using the 'PointerToRawData' in the referenced section headers as
// a key, arrange the elements in the table in ascending order. In other
// words, sort the section headers according to the disk-file offset of
// the section.
//
for (Index = 0; Index < mNtHeader.Pe32->FileHeader.NumberOfSections; Index++) {
Pos = Index;
while ((Pos > 0) && (Section->PointerToRawData < SectionHeader[Pos - 1].PointerToRawData)) {
CopyMem (&SectionHeader[Pos], &SectionHeader[Pos - 1], sizeof (EFI_IMAGE_SECTION_HEADER));
Pos--;
}
CopyMem (&SectionHeader[Pos], Section, sizeof (EFI_IMAGE_SECTION_HEADER));
Section += 1;
}
//
// 13. Walk through the sorted table, bring the corresponding section
// into memory, and hash the entire section (using the 'SizeOfRawData'
// field in the section header to determine the amount of data to hash).
// 14. Add the section's 'SizeOfRawData' to SUM_OF_BYTES_HASHED .
// 15. Repeat steps 13 and 14 for all the sections in the sorted table.
//
for (Index = 0; Index < mNtHeader.Pe32->FileHeader.NumberOfSections; Index++) {
Section = &SectionHeader[Index];
if (Section->SizeOfRawData == 0) {
continue;
}
HashBase = mImageBase + Section->PointerToRawData;
HashSize = (UINTN) Section->SizeOfRawData;
Status = mHash[HashAlg].HashUpdate(HashCtx, HashBase, HashSize);
if (!Status) {
goto Done;
}
SumOfBytesHashed += HashSize;
}
//
// 16. If the file size is greater than SUM_OF_BYTES_HASHED, there is extra
// data in the file that needs to be added to the hash. This data begins
// at file offset SUM_OF_BYTES_HASHED and its length is:
// FileSize - (CertDirectory->Size)
//
if (mImageSize > SumOfBytesHashed) {
HashBase = mImageBase + SumOfBytesHashed;
if (NumberOfRvaAndSizes <= EFI_IMAGE_DIRECTORY_ENTRY_SECURITY) {
CertSize = 0;
} else {
if (mNtHeader.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
CertSize = mNtHeader.Pe32->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY].Size;
} else {
//
// Use PE32+ offset.
//
CertSize = mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY].Size;
}
}
if (mImageSize > CertSize + SumOfBytesHashed) {
HashSize = (UINTN) (mImageSize - CertSize - SumOfBytesHashed);
Status = mHash[HashAlg].HashUpdate(HashCtx, HashBase, HashSize);
if (!Status) {
goto Done;
}
} else if (mImageSize < CertSize + SumOfBytesHashed) {
Status = FALSE;
goto Done;
}
}
Status = mHash[HashAlg].HashFinal(HashCtx, mImageDigest);
Done:
if (HashCtx != NULL) {
FreePool (HashCtx);
}
if (SectionHeader != NULL) {
FreePool (SectionHeader);
}
return Status;
}
/**
Recognize the Hash algorithm in PE/COFF Authenticode and calculate hash of
Pe/Coff image based on the authenticode image hashing in PE/COFF Specification
8.0 Appendix A
Caution: This function may receive untrusted input.
PE/COFF image is external input, so this function will validate its data structure
within this image buffer before use.
@param[in] AuthData Pointer to the Authenticode Signature retrieved from signed image.
@param[in] AuthDataSize Size of the Authenticode Signature in bytes.
@retval EFI_UNSUPPORTED Hash algorithm is not supported.
@retval EFI_SUCCESS Hash successfully.
**/
EFI_STATUS
HashPeImageByType (
IN UINT8 *AuthData,
IN UINTN AuthDataSize
)
{
UINT8 Index;
for (Index = 0; Index < HASHALG_MAX; Index++) {
//
// Check the Hash algorithm in PE/COFF Authenticode.
// According to PKCS#7 Definition:
// SignedData ::= SEQUENCE {
// version Version,
// digestAlgorithms DigestAlgorithmIdentifiers,
// contentInfo ContentInfo,
// .... }
// The DigestAlgorithmIdentifiers can be used to determine the hash algorithm in PE/COFF hashing
// This field has the fixed offset (+32) in final Authenticode ASN.1 data.
// Fixed offset (+32) is calculated based on two bytes of length encoding.
//
if ((*(AuthData + 1) & TWO_BYTE_ENCODE) != TWO_BYTE_ENCODE) {
//
// Only support two bytes of Long Form of Length Encoding.
//
continue;
}
if (AuthDataSize < 32 + mHash[Index].OidLength) {
return EFI_UNSUPPORTED;
}
if (CompareMem (AuthData + 32, mHash[Index].OidValue, mHash[Index].OidLength) == 0) {
break;
}
}
if (Index == HASHALG_MAX) {
return EFI_UNSUPPORTED;
}
//
// HASH PE Image based on Hash algorithm in PE/COFF Authenticode.
//
if (!HashPeImage(Index)) {
return EFI_UNSUPPORTED;
}
return EFI_SUCCESS;
}
/**
Returns the size of a given image execution info table in bytes.
This function returns the size, in bytes, of the image execution info table specified by
ImageExeInfoTable. If ImageExeInfoTable is NULL, then 0 is returned.
@param ImageExeInfoTable A pointer to a image execution info table structure.
@retval 0 If ImageExeInfoTable is NULL.
@retval Others The size of a image execution info table in bytes.
**/
UINTN
GetImageExeInfoTableSize (
EFI_IMAGE_EXECUTION_INFO_TABLE *ImageExeInfoTable
)
{
UINTN Index;
EFI_IMAGE_EXECUTION_INFO *ImageExeInfoItem;
UINTN TotalSize;
if (ImageExeInfoTable == NULL) {
return 0;
}
ImageExeInfoItem = (EFI_IMAGE_EXECUTION_INFO *) ((UINT8 *) ImageExeInfoTable + sizeof (EFI_IMAGE_EXECUTION_INFO_TABLE));
TotalSize = sizeof (EFI_IMAGE_EXECUTION_INFO_TABLE);
for (Index = 0; Index < ImageExeInfoTable->NumberOfImages; Index++) {
TotalSize += ReadUnaligned32 ((UINT32 *) &ImageExeInfoItem->InfoSize);
ImageExeInfoItem = (EFI_IMAGE_EXECUTION_INFO *) ((UINT8 *) ImageExeInfoItem + ReadUnaligned32 ((UINT32 *) &ImageExeInfoItem->InfoSize));
}
return TotalSize;
}
/**
Create an Image Execution Information Table entry and add it to system configuration table.
@param[in] Action Describes the action taken by the firmware regarding this image.
@param[in] Name Input a null-terminated, user-friendly name.
@param[in] DevicePath Input device path pointer.
@param[in] Signature Input signature info in EFI_SIGNATURE_LIST data structure.
@param[in] SignatureSize Size of signature. Must be zero if Signature is NULL.
**/
VOID
AddImageExeInfo (
IN EFI_IMAGE_EXECUTION_ACTION Action,
IN CHAR16 *Name OPTIONAL,
IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath,
IN EFI_SIGNATURE_LIST *Signature OPTIONAL,
IN UINTN SignatureSize
)
{
EFI_IMAGE_EXECUTION_INFO_TABLE *ImageExeInfoTable;
EFI_IMAGE_EXECUTION_INFO_TABLE *NewImageExeInfoTable;
EFI_IMAGE_EXECUTION_INFO *ImageExeInfoEntry;
UINTN ImageExeInfoTableSize;
UINTN NewImageExeInfoEntrySize;
UINTN NameStringLen;
UINTN DevicePathSize;
CHAR16 *NameStr;
ImageExeInfoTable = NULL;
NewImageExeInfoTable = NULL;
ImageExeInfoEntry = NULL;
NameStringLen = 0;
NameStr = NULL;
if (DevicePath == NULL) {
return ;
}
if (Name != NULL) {
NameStringLen = StrSize (Name);
} else {
NameStringLen = sizeof (CHAR16);
}
EfiGetSystemConfigurationTable (&gEfiImageSecurityDatabaseGuid, (VOID **) &ImageExeInfoTable);
if (ImageExeInfoTable != NULL) {
//
// The table has been found!
// We must enlarge the table to accommodate the new exe info entry.
//
ImageExeInfoTableSize = GetImageExeInfoTableSize (ImageExeInfoTable);
} else {
//
// Not Found!
// We should create a new table to append to the configuration table.
//
ImageExeInfoTableSize = sizeof (EFI_IMAGE_EXECUTION_INFO_TABLE);
}
DevicePathSize = GetDevicePathSize (DevicePath);
//
// Signature size can be odd. Pad after signature to ensure next EXECUTION_INFO entry align
//
ASSERT (Signature != NULL || SignatureSize == 0);
NewImageExeInfoEntrySize = sizeof (EFI_IMAGE_EXECUTION_INFO) + NameStringLen + DevicePathSize + SignatureSize;
NewImageExeInfoTable = (EFI_IMAGE_EXECUTION_INFO_TABLE *) AllocateRuntimePool (ImageExeInfoTableSize + NewImageExeInfoEntrySize);
if (NewImageExeInfoTable == NULL) {
return ;
}
if (ImageExeInfoTable != NULL) {
CopyMem (NewImageExeInfoTable, ImageExeInfoTable, ImageExeInfoTableSize);
} else {
NewImageExeInfoTable->NumberOfImages = 0;
}
NewImageExeInfoTable->NumberOfImages++;
ImageExeInfoEntry = (EFI_IMAGE_EXECUTION_INFO *) ((UINT8 *) NewImageExeInfoTable + ImageExeInfoTableSize);
//
// Update new item's information.
//
WriteUnaligned32 ((UINT32 *) ImageExeInfoEntry, Action);
WriteUnaligned32 ((UINT32 *) ((UINT8 *) ImageExeInfoEntry + sizeof (EFI_IMAGE_EXECUTION_ACTION)), (UINT32) NewImageExeInfoEntrySize);
NameStr = (CHAR16 *)(ImageExeInfoEntry + 1);
if (Name != NULL) {
CopyMem ((UINT8 *) NameStr, Name, NameStringLen);
} else {
ZeroMem ((UINT8 *) NameStr, sizeof (CHAR16));
}
CopyMem (
(UINT8 *) NameStr + NameStringLen,
DevicePath,
DevicePathSize
);
if (Signature != NULL) {
CopyMem (
(UINT8 *) NameStr + NameStringLen + DevicePathSize,
Signature,
SignatureSize
);
}
//
// Update/replace the image execution table.
//
gBS->InstallConfigurationTable (&gEfiImageSecurityDatabaseGuid, (VOID *) NewImageExeInfoTable);
//
// Free Old table data!
//
if (ImageExeInfoTable != NULL) {
FreePool (ImageExeInfoTable);
}
}
/**
Check whether the hash of an given X.509 certificate is in forbidden database (DBX).
@param[in] Certificate Pointer to X.509 Certificate that is searched for.
@param[in] CertSize Size of X.509 Certificate.
@param[in] SignatureList Pointer to the Signature List in forbidden database.
@param[in] SignatureListSize Size of Signature List.
@param[out] RevocationTime Return the time that the certificate was revoked.
@param[out] IsFound Search result. Only valid if EFI_SUCCESS returned.
@retval EFI_SUCCESS Finished the search without any error.
@retval Others Error occurred in the search of database.
**/
EFI_STATUS
IsCertHashFoundInDbx (
IN UINT8 *Certificate,
IN UINTN CertSize,
IN EFI_SIGNATURE_LIST *SignatureList,
IN UINTN SignatureListSize,
OUT EFI_TIME *RevocationTime,
OUT BOOLEAN *IsFound
)
{
EFI_STATUS Status;
EFI_SIGNATURE_LIST *DbxList;
UINTN DbxSize;
EFI_SIGNATURE_DATA *CertHash;
UINTN CertHashCount;
UINTN Index;
UINT32 HashAlg;
VOID *HashCtx;
UINT8 CertDigest[MAX_DIGEST_SIZE];
UINT8 *DbxCertHash;
UINTN SiglistHeaderSize;
UINT8 *TBSCert;
UINTN TBSCertSize;
Status = EFI_ABORTED;
*IsFound = FALSE;
DbxList = SignatureList;
DbxSize = SignatureListSize;
HashCtx = NULL;
HashAlg = HASHALG_MAX;
if ((RevocationTime == NULL) || (DbxList == NULL)) {
return EFI_INVALID_PARAMETER;
}
//
// Retrieve the TBSCertificate from the X.509 Certificate.
//
if (!X509GetTBSCert (Certificate, CertSize, &TBSCert, &TBSCertSize)) {
return Status;
}
while ((DbxSize > 0) && (SignatureListSize >= DbxList->SignatureListSize)) {
//
// Determine Hash Algorithm of Certificate in the forbidden database.
//
if (CompareGuid (&DbxList->SignatureType, &gEfiCertX509Sha256Guid)) {
HashAlg = HASHALG_SHA256;
} else if (CompareGuid (&DbxList->SignatureType, &gEfiCertX509Sha384Guid)) {
HashAlg = HASHALG_SHA384;
} else if (CompareGuid (&DbxList->SignatureType, &gEfiCertX509Sha512Guid)) {
HashAlg = HASHALG_SHA512;
} else {
DbxSize -= DbxList->SignatureListSize;
DbxList = (EFI_SIGNATURE_LIST *) ((UINT8 *) DbxList + DbxList->SignatureListSize);
continue;
}
//
// Calculate the hash value of current TBSCertificate for comparision.
//
if (mHash[HashAlg].GetContextSize == NULL) {
goto Done;
}
ZeroMem (CertDigest, MAX_DIGEST_SIZE);
HashCtx = AllocatePool (mHash[HashAlg].GetContextSize ());
if (HashCtx == NULL) {
goto Done;
}
if (!mHash[HashAlg].HashInit (HashCtx)) {
goto Done;
}
if (!mHash[HashAlg].HashUpdate (HashCtx, TBSCert, TBSCertSize)) {
goto Done;
}
if (!mHash[HashAlg].HashFinal (HashCtx, CertDigest)) {
goto Done;
}
FreePool (HashCtx);
HashCtx = NULL;
SiglistHeaderSize = sizeof (EFI_SIGNATURE_LIST) + DbxList->SignatureHeaderSize;
CertHash = (EFI_SIGNATURE_DATA *) ((UINT8 *) DbxList + SiglistHeaderSize);
CertHashCount = (DbxList->SignatureListSize - SiglistHeaderSize) / DbxList->SignatureSize;
for (Index = 0; Index < CertHashCount; Index++) {
//
// Iterate each Signature Data Node within this CertList for verify.
//
DbxCertHash = CertHash->SignatureData;
if (CompareMem (DbxCertHash, CertDigest, mHash[HashAlg].DigestLength) == 0) {
//
// Hash of Certificate is found in forbidden database.
//
Status = EFI_SUCCESS;
*IsFound = TRUE;
//
// Return the revocation time.
//
CopyMem (RevocationTime, (EFI_TIME *)(DbxCertHash + mHash[HashAlg].DigestLength), sizeof (EFI_TIME));
goto Done;
}
CertHash = (EFI_SIGNATURE_DATA *) ((UINT8 *) CertHash + DbxList->SignatureSize);
}
DbxSize -= DbxList->SignatureListSize;
DbxList = (EFI_SIGNATURE_LIST *) ((UINT8 *) DbxList + DbxList->SignatureListSize);
}
Status = EFI_SUCCESS;
Done:
if (HashCtx != NULL) {
FreePool (HashCtx);
}
return Status;
}
/**
Check whether signature is in specified database.
@param[in] VariableName Name of database variable that is searched in.
@param[in] Signature Pointer to signature that is searched for.
@param[in] CertType Pointer to hash algorithm.
@param[in] SignatureSize Size of Signature.
@param[out] IsFound Search result. Only valid if EFI_SUCCESS returned
@retval EFI_SUCCESS Finished the search without any error.
@retval Others Error occurred in the search of database.
**/
EFI_STATUS
IsSignatureFoundInDatabase (
IN CHAR16 *VariableName,
IN UINT8 *Signature,
IN EFI_GUID *CertType,
IN UINTN SignatureSize,
OUT BOOLEAN *IsFound
)
{
EFI_STATUS Status;
EFI_SIGNATURE_LIST *CertList;
EFI_SIGNATURE_DATA *Cert;
UINTN DataSize;
UINT8 *Data;
UINTN Index;
UINTN CertCount;
//
// Read signature database variable.
//
*IsFound = FALSE;
Data = NULL;
DataSize = 0;
Status = gRT->GetVariable (VariableName, &gEfiImageSecurityDatabaseGuid, NULL, &DataSize, NULL);
if (Status != EFI_BUFFER_TOO_SMALL) {
if (Status == EFI_NOT_FOUND) {
//
// No database, no need to search.
//
Status = EFI_SUCCESS;
}
return Status;
}
Data = (UINT8 *) AllocateZeroPool (DataSize);
if (Data == NULL) {