DxeImageVerificationLib.c revision 4fd606d1f5abe38e1f42c38de1d2e895166bd0f4
/** @file
Implement image verification services for secure boot service in UEFI2.3.1.
Copyright (c) 2009 - 2012, 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
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 "DxeImageVerificationLib.h"
//
// Notify string for authorization UI.
//
CHAR16 mNotifyString1[MAX_NOTIFY_STRING_LEN] = L"Image verification pass but not found in authorized database!";
//
// Public Exponent of RSA Key.
//
//
// OID ASN.1 Value for Hash Algorithms
//
UINT8 mHashOidValue[] = {
0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x02, 0x05, // OBJ_md5
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"SHA256", 32, &mHashOidValue[22], 9, Sha256GetContextSize,Sha256Init, Sha256Update, Sha256Final},
};
/**
@param ReadSize On input, the size in bytes of the requested read operation.
On output, the number of bytes actually read.
**/
)
{
return EFI_INVALID_PARAMETER;
}
return EFI_INVALID_PARAMETER;
}
if (EndPosition > mImageSize) {
}
if (FileOffset >= mImageSize) {
*ReadSize = 0;
}
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
**/
)
{
//
// First check to see if File is from a Firmware Volume
//
DeviceHandle = NULL;
);
NULL,
NULL,
NULL,
);
return IMAGE_FROM_FV;
}
}
//
// Next check to see if File is from a Block I/O device
//
DeviceHandle = NULL;
);
NULL,
NULL,
);
//
// 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;
);
//
// 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.
//
while (!IsDevicePathEndType (TempDevicePath)) {
switch (DevicePathType (TempDevicePath)) {
case MEDIA_DEVICE_PATH:
return IMAGE_FROM_OPTION_ROM;
}
break;
case MESSAGING_DEVICE_PATH:
return IMAGE_FROM_REMOVABLE_MEDIA;
}
break;
default:
break;
}
}
return IMAGE_UNKNOWN;
}
/**
@param[in] HashAlg Hash algorithm type.
@retval TRUE Successfully hash image.
@retval FALSE Fail in hash image.
**/
)
{
return FALSE;
}
//
// Initialize context of hash.
//
if (HashAlg == HASHALG_SHA1) {
} else if (HashAlg == HASHALG_SHA256) {
} else {
return FALSE;
}
return FALSE;
}
// 1. Load the image header into memory.
// 2. Initialize a SHA hash context.
if (!Status) {
goto Done;
}
//
// 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.
//
if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
} else if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC) {
//
// Use PE32+ offset.
//
} else {
//
// Invalid header magic number.
//
goto Done;
}
if (!Status) {
goto Done;
}
//
// 5. Skip over the image checksum (it occupies a single ULONG).
//
//
// 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 (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
} else {
//
// Use PE32+ offset.
//
}
if (HashSize != 0) {
if (!Status) {
goto Done;
}
}
} else {
//
// 7. Hash everything from the end of the checksum to the start of the Cert Directory.
//
if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
HashSize = (UINTN) ((UINT8 *) (&mNtHeader.Pe32->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY]) - HashBase);
} else {
//
// Use PE32+ offset.
//
HashSize = (UINTN) ((UINT8 *) (&mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY]) - HashBase);
}
if (HashSize != 0) {
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 (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset
//
HashBase = (UINT8 *) &mNtHeader.Pe32->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY + 1];
} else {
//
// Use PE32+ offset.
//
HashBase = (UINT8 *) &mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY + 1];
}
if (HashSize != 0) {
if (!Status) {
goto Done;
}
}
}
//
// 10. Set the SUM_OF_BYTES_HASHED to the size of the header.
//
if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
} else {
//
// Use PE32+ offset
//
}
Section = (EFI_IMAGE_SECTION_HEADER *) (
sizeof (UINT32) +
sizeof (EFI_IMAGE_FILE_HEADER) +
);
//
// 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) {
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.
//
Pos--;
}
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.
//
if (Section->SizeOfRawData == 0) {
continue;
}
if (!Status) {
goto Done;
}
}
//
// 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) {
CertSize = 0;
} else {
if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
} else {
//
// Use PE32+ offset.
//
CertSize = mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY].Size;
}
}
if (!Status) {
goto Done;
}
goto Done;
}
}
Done:
}
if (SectionHeader != NULL) {
}
return Status;
}
/**
8.0 Appendix A
@retval EFI_UNSUPPORTED Hash algorithm is not supported.
@retval EFI_SUCCESS Hash successfully.
**/
)
{
return EFI_UNSUPPORTED;
}
//
// According to PKCS#7 Definition:
// SignedData ::= SEQUENCE {
// version Version,
// digestAlgorithms DigestAlgorithmIdentifiers,
// contentInfo ContentInfo,
// .... }
// 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.
//
//
// Only support two bytes of Long Form of Length Encoding.
//
continue;
}
return EFI_UNSUPPORTED;
}
break;
}
}
if (Index == HASHALG_MAX) {
return EFI_UNSUPPORTED;
}
//
//
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.
**/
)
{
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);
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.
**/
)
{
NameStringLen = 0;
if (DevicePath == NULL) {
return ;
}
}
if (ImageExeInfoTable != NULL) {
//
// The table has been found!
// We must enlarge the table to accmodate the new exe info entry.
//
} else {
//
// Not Found!
// We should create a new table to append to the configuration table.
//
ImageExeInfoTableSize = sizeof (EFI_IMAGE_EXECUTION_INFO_TABLE);
}
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) {
} else {
}
ImageExeInfoEntry = (EFI_IMAGE_EXECUTION_INFO *) ((UINT8 *) NewImageExeInfoTable + ImageExeInfoTableSize);
//
// Update new item's infomation.
//
}
CopyMem (
);
CopyMem (
);
}
//
//
//
// Free Old table data!
//
if (ImageExeInfoTable != NULL) {
}
}
/**
Discover if the UEFI image is authorized by user's policy setting.
@param[in] Policy Specify platform's policy setting.
@retval EFI_ACCESS_DENIED Image is not allowed to run.
@retval EFI_SECURITY_VIOLATION Image is deferred.
@retval EFI_SUCCESS Image is authorized to run.
**/
)
{
switch (Policy) {
do {
break;
break;
break;
}
} while (TRUE);
break;
break;
break;
break;
}
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 algrithom.
@param[in] SignatureSize Size of Signature.
@return TRUE Found the signature in the variable database.
@return FALSE Not found the signature in the variable database.
**/
)
{
//
// Read signature database variable.
//
DataSize = 0;
if (Status != EFI_BUFFER_TOO_SMALL) {
return FALSE;
}
return FALSE;
}
goto Done;
}
//
// Enumerate all signature data in SigDB to check if executable's signature exists.
//
CertCount = (CertList->SignatureListSize - CertList->SignatureHeaderSize) / CertList->SignatureSize;
Cert = (EFI_SIGNATURE_DATA *) ((UINT8 *) CertList + sizeof (EFI_SIGNATURE_LIST) + CertList->SignatureHeaderSize);
if ((CertList->SignatureSize == sizeof(EFI_SIGNATURE_DATA) - 1 + SignatureSize) && (CompareGuid(&CertList->SignatureType, CertType))) {
//
// Find the signature in database.
//
break;
}
}
if (IsFound) {
break;
}
}
}
Done:
}
return IsFound;
}
/**
Verify PKCS#7 SignedData using certificate found in Variable which formatted
as EFI_SIGNATURE_LIST. The Variable may be PK, KEK, DB or DBX.
@param VariableName Name of Variable to search for Certificate.
@param VendorGuid Variable vendor GUID.
@retval TRUE Image pass verification.
@retval FALSE Image fail verification.
**/
)
{
RootCertSize = 0;
DataSize = 0;
if (Status == EFI_BUFFER_TOO_SMALL) {
return VerifyStatus;
}
goto Done;
}
//
// Find X509 certificate in Signature List to verify the signature in pkcs7 signed data.
//
Cert = (EFI_SIGNATURE_DATA *) ((UINT8 *) CertList + sizeof (EFI_SIGNATURE_LIST) + CertList->SignatureHeaderSize);
CertCount = (CertList->SignatureListSize - sizeof (EFI_SIGNATURE_LIST) - CertList->SignatureHeaderSize) / CertList->SignatureSize;
//
// Iterate each Signature Data Node within this CertList for verify.
//
//
// Call AuthenticodeVerify library to Verify Authenticode struct.
//
);
if (VerifyStatus) {
goto Done;
}
}
}
}
}
Done:
}
return VerifyStatus;
}
/**
Verify certificate in WIN_CERT_TYPE_PKCS_SIGNED_DATA format.
@retval EFI_SUCCESS Image pass verification.
@retval EFI_SECURITY_VIOLATION Image fail verification.
**/
)
{
//
// 1: Find certificate from DBX forbidden database for revoked certificate.
//
if (IsPkcsSignedDataVerifiedBySignatureList (EFI_IMAGE_SECURITY_DATABASE1, &gEfiImageSecurityDatabaseGuid)) {
//
// DBX is forbidden database, if Authenticode verification pass with
// one of the certificate in DBX, this image should be rejected.
//
return EFI_SECURITY_VIOLATION;
}
//
// 2: Find certificate from KEK database and try to verify authenticode struct.
//
return EFI_SUCCESS;
}
//
// 3: Find certificate from DB database and try to verify authenticode struct.
//
if (IsPkcsSignedDataVerifiedBySignatureList (EFI_IMAGE_SECURITY_DATABASE, &gEfiImageSecurityDatabaseGuid)) {
return EFI_SUCCESS;
} else {
return EFI_SECURITY_VIOLATION;
}
}
/**
Verify certificate in WIN_CERTIFICATE_UEFI_GUID format.
@retval EFI_SUCCESS Image pass verification.
@retval EFI_SECURITY_VIOLATION Image fail verification.
@retval other error value
**/
)
{
KekDataSize = 0;
//
// Invalid Certificate Data Type.
//
return EFI_SECURITY_VIOLATION;
}
//
// Get KEK database variable data size
//
Result = gRT->GetVariable (EFI_KEY_EXCHANGE_KEY_NAME, &gEfiGlobalVariableGuid, NULL, &KekDataSize, NULL);
if (Result != EFI_BUFFER_TOO_SMALL) {
return EFI_SECURITY_VIOLATION;
}
//
// Get KEK database variable.
//
return EFI_SECURITY_VIOLATION;
}
//
// Enumerate all Kek items in this list to verify the variable certificate data.
// If anyone is authenticated successfully, it means the variable is correct!
//
KekItem = (EFI_SIGNATURE_DATA *) ((UINT8 *) KekList + sizeof (EFI_SIGNATURE_LIST) + KekList->SignatureHeaderSize);
KekCount = (KekList->SignatureListSize - sizeof (EFI_SIGNATURE_LIST) - KekList->SignatureHeaderSize) / KekList->SignatureSize;
break;
}
}
}
}
if (!IsFound) {
//
// Signed key is not a trust one.
//
goto Done;
}
//
// Now, we found the corresponding security policy.
// Verify the data payload.
//
goto Done;
}
//
// Set RSA Key Components.
// NOTE: Only N and E are needed to be set as RSA public key for signature verification.
//
if (!Status) {
goto Done;
}
if (!Status) {
goto Done;
}
//
// Verify the signature.
//
Status = RsaPkcs1Verify (
Rsa,
);
Done:
}
}
if (Status) {
return EFI_SUCCESS;
} else {
return EFI_SECURITY_VIOLATION;
}
}
/**
Provide verification service for signed images, which include both signature validation
and platform policy control. For signature types, both UEFI WIN_CERTIFICATE_UEFI_GUID and
MSFT Authenticode type signatures are supported.
In this implementation, only verify external executables when in USER MODE.
Executables from FV is bypass, so pass in AuthenticationStatus is ignored.
The image verification process is:
Is the Image signed?
If yes,
Does the image verify against a certificate (root or intermediate) in the allowed db?
Run it
Image verification fail
Is the Image's Hash not in forbidden database and the Image's Hash in allowed db?
Run it
If no,
Is the Image's Hash in the forbidden database (DBX)?
if yes,
Error out
Is the Image's Hash in the allowed database (DB)?
If yes,
Run it
If no,
Error out
@param[in] AuthenticationStatus
This is the authentication status returned from the security
measurement services for the input file.
@param[in] File This is a pointer to the device path of the file that is
being dispatched. This will optionally be used for logging.
@param[in] FileBuffer File buffer matches the input file device path.
@param[in] FileSize Size of File buffer matches the input file device path.
@retval EFI_SUCCESS The file specified by File did authenticate, and the
platform policy dictates that the DXE Core may use File.
@retval EFI_INVALID_PARAMETER Input argument is incorrect.
@retval EFI_OUT_RESOURCE Fail to allocate memory.
@retval EFI_SECURITY_VIOLATION The file specified by File did not authenticate, and
the platform policy dictates that File should be placed
in the untrusted state. A file may be promoted from
the untrusted to the trusted state at a future time
with a call to the Trust() DXE Service.
@retval EFI_ACCESS_DENIED The file specified by File did not authenticate, and
the platform policy dictates that File should not be
used for any purpose.
**/
)
{
return EFI_INVALID_PARAMETER;
}
SignatureListSize = 0;
//
// Check the image type and get policy setting.
//
switch (GetImageType (File)) {
case IMAGE_FROM_FV:
break;
case IMAGE_FROM_OPTION_ROM:
break;
break;
case IMAGE_FROM_FIXED_MEDIA:
break;
default:
break;
}
//
//
if (Policy == ALWAYS_EXECUTE) {
return EFI_SUCCESS;
} else if (Policy == NEVER_EXECUTE) {
return EFI_ACCESS_DENIED;
}
//
// Skip verification if SecureBootEnable variable doesn't exist.
//
if (SecureBootEnable == NULL) {
return EFI_SUCCESS;
}
//
// Skip verification if SecureBootEnable is disabled.
//
if (*SecureBootEnable == SECURE_BOOT_DISABLE) {
return EFI_SUCCESS;
}
//
// SetupMode doesn't exist means no AuthVar driver is dispatched,
// skip verification.
//
return EFI_SUCCESS;
}
//
// If platform is in SETUP MODE, skip verification.
//
if (*SetupMode == SETUP_MODE) {
return EFI_SUCCESS;
}
//
// Read the Dos header.
//
if (FileBuffer == NULL) {
return EFI_INVALID_PARAMETER;
}
//
// Get information about the image being loaded
//
//
// The information can't be got from the invalid PeImage
//
goto Done;
}
//
// DOS image header is present,
// so read the PE header after the DOS image header.
//
} else {
mPeCoffHeaderOffset = 0;
}
//
//
//
//
goto Done;
}
if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
mSecDataDir = (EFI_IMAGE_DATA_DIRECTORY *) &mNtHeader.Pe32->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY];
}
} else {
//
// Use PE32+ offset.
//
mSecDataDir = (EFI_IMAGE_DATA_DIRECTORY *) &mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY];
}
}
//
// This image is not signed.
//
if (!HashPeImage (HASHALG_SHA256)) {
goto Done;
}
if (IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE1, mImageDigest, &mCertType, mImageDigestSize)) {
//
// Image Hash is in forbidden database (DBX).
//
goto Done;
}
if (IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE, mImageDigest, &mCertType, mImageDigestSize)) {
//
// Image Hash is in allowed database (DB).
//
return EFI_SUCCESS;
}
//
// Image Hash is not found in both forbidden and allowed database.
//
goto Done;
}
//
// Verify signature of executables.
//
CertSize = sizeof (WIN_CERTIFICATE);
goto Done;
}
switch (WinCertificate->wCertificateType) {
case WIN_CERT_TYPE_EFI_GUID:
CertSize = sizeof (WIN_CERTIFICATE_UEFI_GUID) + sizeof (EFI_CERT_BLOCK_RSA_2048_SHA256) - sizeof (UINT8);
goto Done;
}
//
// Verify UEFI GUID type.
//
if (!HashPeImage (HASHALG_SHA256)) {
goto Done;
}
break;
//
// Verify Pkcs signed data type.
//
Status = HashPeImageByType();
goto Done;
}
//
// For image verification against enrolled certificate(root or intermediate),
// no need to check image's hash in the allowed database.
//
if (!EFI_ERROR (VerifyStatus)) {
if (!IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE1, mImageDigest, &mCertType, mImageDigestSize)) {
return EFI_SUCCESS;
}
}
break;
default:
goto Done;
}
//
// Get image hash value as executable's signature.
//
SignatureListSize = sizeof (EFI_SIGNATURE_LIST) + sizeof (EFI_SIGNATURE_DATA) - 1 + mImageDigestSize;
if (SignatureList == NULL) {
goto Done;
}
//
// Signature database check after verification.
//
if (EFI_ERROR (VerifyStatus)) {
//
// Verification failure.
//
if (!IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE1, mImageDigest, &mCertType, mImageDigestSize) &&
IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE, mImageDigest, &mCertType, mImageDigestSize)) {
//
// Verification fail, Image Hash is not in forbidden database (DBX),
// and Image Hash is in allowed database (DB).
//
} else {
}
} else if (IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE1, Signature->SignatureData, &mCertType, mImageDigestSize)) {
//
// Executable signature verification passes, but is found in forbidden signature database.
//
} else if (IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE, Signature->SignatureData, &mCertType, mImageDigestSize)) {
//
// Executable signature is found in authorized signature database.
//
} else {
//
// Executable signature verification passes, but cannot be found in authorized signature database.
// Get platform policy to determine the action.
//
}
Done:
if (Status != EFI_SUCCESS) {
//
// Policy decides to defer or reject the image; add its information in image executable information table.
//
}
if (SignatureList != NULL) {
}
return Status;
}
/**
When VariableWriteArchProtocol install, create "SecureBoot" variable.
@param[in] Event Event whose notification function is being invoked.
@param[in] Context Pointer to the notification function's context.
**/
)
{
return;
}
//
// Check whether "SecureBoot" variable exists.
// If this library is built-in, it means firmware has capability to perform
// driver signing verification.
//
if (SecureBootModePtr == NULL) {
//
// Authenticated variable driver will update "SecureBoot" depending on SetupMode variable.
//
gRT->SetVariable (
sizeof (UINT8),
);
} else {
}
}
/**
Register security measurement handler.
@param ImageHandle ImageHandle of the loaded driver.
@param SystemTable Pointer to the EFI System Table.
@retval EFI_SUCCESS The handlers were registered successfully.
**/
)
{
//
// Register callback function upon VariableWriteArchProtocol.
//
NULL,
);
return RegisterSecurityHandler (
);
}