From 0c18794ea4289f03fefc7117b56740414cc0536c Mon Sep 17 00:00:00 2001 From: gdong1 Date: Fri, 2 Sep 2011 07:49:32 +0000 Subject: Add security package to repository. git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@12261 6f19259b-4bc3-4df7-8a09-765794883524 --- .../DxeImageVerificationLib.c | 1368 ++++++++++++++++++++ 1 file changed, 1368 insertions(+) create mode 100644 SecurityPkg/Library/DxeImageVerificationLib/DxeImageVerificationLib.c (limited to 'SecurityPkg/Library/DxeImageVerificationLib/DxeImageVerificationLib.c') diff --git a/SecurityPkg/Library/DxeImageVerificationLib/DxeImageVerificationLib.c b/SecurityPkg/Library/DxeImageVerificationLib/DxeImageVerificationLib.c new file mode 100644 index 0000000000..148dbd5a89 --- /dev/null +++ b/SecurityPkg/Library/DxeImageVerificationLib/DxeImageVerificationLib.c @@ -0,0 +1,1368 @@ +/** @file + Implement image verification services for secure boot service in UEFI2.3.1. + +Copyright (c) 2009 - 2011, Intel Corporation. All rights reserved.
+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 "DxeImageVerificationLib.h" + +EFI_IMAGE_OPTIONAL_HEADER_PTR_UNION mNtHeader; +UINTN mImageSize; +UINT32 mPeCoffHeaderOffset; +UINT8 mImageDigest[MAX_DIGEST_SIZE]; +UINTN mImageDigestSize; +EFI_IMAGE_DATA_DIRECTORY *mSecDataDir = NULL; +UINT8 *mImageBase = NULL; +EFI_GUID mCertType; + +// +// 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[] = { + 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"SHA1", 20, &mHashOidValue[8], 5, Sha1GetContextSize, Sha1Init, Sha1Update, Sha1Final }, + { L"SHA224", 28, &mHashOidValue[13], 9, NULL, NULL, NULL, NULL }, + { L"SHA256", 32, &mHashOidValue[22], 9, Sha256GetContextSize,Sha256Init, Sha256Update, Sha256Final}, + { L"SHA384", 48, &mHashOidValue[31], 9, NULL, NULL, NULL, NULL }, + { L"SHA512", 64, &mHashOidValue[40], 9, NULL, NULL, NULL, NULL } +}; + + +/** + 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; + + // + // 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; +} + +/** + Caculate hash of Pe/Coff image based on the authenticode image hashing in + PE/COFF Specification 8.0 Appendix A + + @param[in] HashAlg Hash algorithm type. + + @retval TRUE Successfully hash image. + @retval FALSE Fail in hash image. + +**/ +BOOLEAN +HashPeImage ( + IN UINT32 HashAlg + ) +{ + BOOLEAN Status; + UINT16 Magic; + EFI_IMAGE_SECTION_HEADER *Section; + VOID *HashCtx; + UINTN CtxSize; + UINT8 *HashBase; + UINTN HashSize; + UINTN SumOfBytesHashed; + EFI_IMAGE_SECTION_HEADER *SectionHeader; + UINTN Index; + UINTN Pos; + + HashCtx = NULL; + SectionHeader = NULL; + Status = FALSE; + + if ((HashAlg != HASHALG_SHA1) && (HashAlg != HASHALG_SHA256)) { + return FALSE; + } + + // + // Initialize context of hash. + // + ZeroMem (mImageDigest, MAX_DIGEST_SIZE); + + if (HashAlg == HASHALG_SHA1) { + mImageDigestSize = SHA1_DIGEST_SIZE; + mCertType = gEfiCertSha1Guid; + } else if (HashAlg == HASHALG_SHA256) { + mImageDigestSize = SHA256_DIGEST_SIZE; + mCertType = gEfiCertSha256Guid; + } else { + return FALSE; + } + + CtxSize = mHash[HashAlg].GetContextSize(); + + HashCtx = AllocatePool (CtxSize); + ASSERT (HashCtx != NULL); + + // 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 + // + Magic = mNtHeader.Pe32->OptionalHeader.Magic; + // + // 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 (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) { + // + // Use PE32 offset. + // + HashSize = (UINTN) ((UINT8 *) (&mNtHeader.Pe32->OptionalHeader.CheckSum) - HashBase); + } else { + // + // Use PE32+ offset. + // + HashSize = (UINTN) ((UINT8 *) (&mNtHeader.Pe32Plus->OptionalHeader.CheckSum) - HashBase); + } + + Status = mHash[HashAlg].HashUpdate(HashCtx, HashBase, HashSize); + if (!Status) { + goto Done; + } + // + // 5. Skip over the image checksum (it occupies a single ULONG). + // 6. Get the address of the beginning of the Cert Directory. + // 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. + // + HashBase = (UINT8 *) &mNtHeader.Pe32->OptionalHeader.CheckSum + sizeof (UINT32); + HashSize = (UINTN) ((UINT8 *) (&mNtHeader.Pe32->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY]) - HashBase); + } else { + // + // Use PE32+ offset. + // + HashBase = (UINT8 *) &mNtHeader.Pe32Plus->OptionalHeader.CheckSum + sizeof (UINT32); + HashSize = (UINTN) ((UINT8 *) (&mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY]) - HashBase); + } + + 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 (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) ((UINT8 *) (&mNtHeader.Pe32->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY + 1]) - mImageBase); + } else { + // + // Use PE32+ offset. + // + HashBase = (UINT8 *) &mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY + 1]; + HashSize = mNtHeader.Pe32Plus->OptionalHeader.SizeOfHeaders - (UINTN) ((UINT8 *) (&mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY + 1]) - mImageBase); + } + + 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 (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) { + // + // Use PE32 offset. + // + SumOfBytesHashed = mNtHeader.Pe32->OptionalHeader.SizeOfHeaders; + } else { + // + // Use PE32+ offset + // + SumOfBytesHashed = mNtHeader.Pe32Plus->OptionalHeader.SizeOfHeaders; + } + + // + // 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); + ASSERT (SectionHeader != NULL); + // + // 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. + // + Section = (EFI_IMAGE_SECTION_HEADER *) ( + mImageBase + + mPeCoffHeaderOffset + + sizeof (UINT32) + + sizeof (EFI_IMAGE_FILE_HEADER) + + mNtHeader.Pe32->FileHeader.SizeOfOptionalHeader + ); + 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 (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) { + // + // Use PE32 offset. + // + HashSize = (UINTN)( + mImageSize - + mNtHeader.Pe32->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY].Size - + SumOfBytesHashed); + } else { + // + // Use PE32+ offset. + // + HashSize = (UINTN)( + mImageSize - + mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY].Size - + SumOfBytesHashed); + } + + Status = mHash[HashAlg].HashUpdate(HashCtx, HashBase, HashSize); + if (!Status) { + 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 caculate hash of + Pe/Coff image based on the authenticode image hashing in PE/COFF Specification + 8.0 Appendix A + + @retval EFI_UNSUPPORTED Hash algorithm is not supported. + @retval EFI_SUCCESS Hash successfully. + +**/ +EFI_STATUS +HashPeImageByType ( + VOID + ) +{ + UINT8 Index; + WIN_CERTIFICATE_EFI_PKCS *PkcsCertData; + + PkcsCertData = (WIN_CERTIFICATE_EFI_PKCS *) (mImageBase + mSecDataDir->VirtualAddress); + + 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. + // + if (CompareMem (PkcsCertData->CertData + 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. + +**/ +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_STATUS Status; + 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; + + ASSERT (DevicePath != NULL); + ImageExeInfoTable = NULL; + NewImageExeInfoTable = NULL; + ImageExeInfoEntry = NULL; + NameStringLen = 0; + + if (Name != NULL) { + NameStringLen = StrSize (Name); + } + + ImageExeInfoTable = NULL; + EfiGetSystemConfigurationTable (&gEfiImageSecurityDatabaseGuid, (VOID**)&ImageExeInfoTable); + if (ImageExeInfoTable != NULL) { + // + // The table has been found! + // We must enlarge the table to accmodate 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); + NewImageExeInfoEntrySize = sizeof (EFI_IMAGE_EXECUTION_INFO) + NameStringLen + DevicePathSize + SignatureSize; + NewImageExeInfoTable = (EFI_IMAGE_EXECUTION_INFO_TABLE *) AllocateRuntimePool (ImageExeInfoTableSize + NewImageExeInfoEntrySize); + ASSERT (NewImageExeInfoTable != NULL); + + 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 infomation. + // + WriteUnaligned32 ((UINT32 *) &ImageExeInfoEntry->Action, Action); + WriteUnaligned32 ((UINT32 *) &ImageExeInfoEntry->InfoSize, (UINT32) NewImageExeInfoEntrySize); + + if (Name != NULL) { + CopyMem ((UINT8 *) &ImageExeInfoEntry->InfoSize + sizeof (UINT32), Name, NameStringLen); + } + CopyMem ( + (UINT8 *) &ImageExeInfoEntry->InfoSize + sizeof (UINT32) + NameStringLen, + DevicePath, + DevicePathSize + ); + if (Signature != NULL) { + CopyMem ( + (UINT8 *) &ImageExeInfoEntry->InfoSize + sizeof (UINT32) + NameStringLen + DevicePathSize, + Signature, + SignatureSize + ); + } + // + // Update/replace the image execution table. + // + Status = gBS->InstallConfigurationTable (&gEfiImageSecurityDatabaseGuid, (VOID *) NewImageExeInfoTable); + ASSERT_EFI_ERROR (Status); + // + // Free Old table data! + // + if (ImageExeInfoTable != NULL) { + FreePool (ImageExeInfoTable); + } +} + +/** + 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. + +**/ +EFI_STATUS +ImageAuthorization ( + IN UINT32 Policy + ) +{ + EFI_STATUS Status; + EFI_INPUT_KEY Key; + + Status = EFI_ACCESS_DENIED; + + switch (Policy) { + + case QUERY_USER_ON_SECURITY_VIOLATION: + do { + CreatePopUp (EFI_LIGHTGRAY | EFI_BACKGROUND_BLUE, &Key, mNotifyString1, mNotifyString2, NULL); + if (Key.UnicodeChar == L'Y' || Key.UnicodeChar == L'y') { + Status = EFI_SUCCESS; + break; + } else if (Key.UnicodeChar == L'N' || Key.UnicodeChar == L'n') { + Status = EFI_ACCESS_DENIED; + break; + } else if (Key.UnicodeChar == L'D' || Key.UnicodeChar == L'd') { + Status = EFI_SECURITY_VIOLATION; + break; + } + } while (TRUE); + break; + + case ALLOW_EXECUTE_ON_SECURITY_VIOLATION: + Status = EFI_SUCCESS; + break; + + case DEFER_EXECUTE_ON_SECURITY_VIOLATION: + Status = EFI_SECURITY_VIOLATION; + break; + + case DENY_EXECUTE_ON_SECURITY_VIOLATION: + Status = EFI_ACCESS_DENIED; + 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. + +**/ +BOOLEAN +IsSignatureFoundInDatabase ( + IN CHAR16 *VariableName, + IN UINT8 *Signature, + IN EFI_GUID *CertType, + IN UINTN SignatureSize + ) +{ + EFI_STATUS Status; + EFI_SIGNATURE_LIST *CertList; + EFI_SIGNATURE_DATA *Cert; + UINTN DataSize; + UINT8 *Data; + UINTN Index; + UINTN CertCount; + BOOLEAN IsFound; + // + // Read signature database variable. + // + IsFound = FALSE; + Data = NULL; + DataSize = 0; + Status = gRT->GetVariable (VariableName, &gEfiImageSecurityDatabaseGuid, NULL, &DataSize, NULL); + if (Status != EFI_BUFFER_TOO_SMALL) { + return FALSE; + } + + Data = (UINT8 *) AllocateZeroPool (DataSize); + ASSERT (Data != NULL); + + Status = gRT->GetVariable (VariableName, &gEfiImageSecurityDatabaseGuid, NULL, &DataSize, Data); + if (EFI_ERROR (Status)) { + goto Done; + } + // + // Enumerate all signature data in SigDB to check if executable's signature exists. + // + CertList = (EFI_SIGNATURE_LIST *) Data; + while ((DataSize > 0) && (DataSize >= CertList->SignatureListSize)) { + 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))) { + for (Index = 0; Index < CertCount; Index++) { + if (CompareMem (Cert->SignatureData, Signature, SignatureSize) == 0) { + // + // Find the signature in database. + // + IsFound = TRUE; + break; + } + + Cert = (EFI_SIGNATURE_DATA *) ((UINT8 *) Cert + CertList->SignatureSize); + } + + if (IsFound) { + break; + } + } + + DataSize -= CertList->SignatureListSize; + CertList = (EFI_SIGNATURE_LIST *) ((UINT8 *) CertList + CertList->SignatureListSize); + } + +Done: + if (Data != NULL) { + FreePool (Data); + } + + return IsFound; +} + +/** + Verify certificate in WIN_CERT_TYPE_PKCS_SIGNED_DATA format . + + @retval EFI_SUCCESS Image pass verification. + @retval EFI_SECURITY_VIOLATION Image fail verification. + @retval other error value + +**/ +EFI_STATUS +VerifyCertPkcsSignedData ( + VOID + ) +{ + EFI_STATUS Status; + BOOLEAN VerifyStatus; + WIN_CERTIFICATE_EFI_PKCS *PkcsCertData; + EFI_SIGNATURE_LIST *CertList; + EFI_SIGNATURE_DATA *Cert; + UINTN DataSize; + UINT8 *Data; + UINT8 *RootCert; + UINTN RootCertSize; + UINTN Index; + UINTN CertCount; + + Data = NULL; + CertList = NULL; + Cert = NULL; + RootCert = NULL; + RootCertSize = 0; + VerifyStatus = FALSE; + PkcsCertData = (WIN_CERTIFICATE_EFI_PKCS *) (mImageBase + mSecDataDir->VirtualAddress); + + // + // 1: Find certificate from KEK database and try to verify authenticode struct. + // + DataSize = 0; + Status = gRT->GetVariable (EFI_KEY_EXCHANGE_KEY_NAME, &gEfiGlobalVariableGuid, NULL, &DataSize, NULL); + if (Status == EFI_BUFFER_TOO_SMALL) { + Data = (UINT8 *)AllocateZeroPool (DataSize); + ASSERT (Data != NULL); + + Status = gRT->GetVariable (EFI_KEY_EXCHANGE_KEY_NAME, &gEfiGlobalVariableGuid, NULL, &DataSize, (VOID *)Data); + if (EFI_ERROR (Status)) { + goto Done; + } + + // + // Find Cert Enrolled in KEK database to verify the signature in pkcs7 signed data. + // + CertList = (EFI_SIGNATURE_LIST *) Data; + while ((DataSize > 0) && (DataSize >= CertList->SignatureListSize)) { + if (CompareGuid (&CertList->SignatureType, &gEfiCertX509Guid)) { + Cert = (EFI_SIGNATURE_DATA *) ((UINT8 *) CertList + sizeof (EFI_SIGNATURE_LIST) + CertList->SignatureHeaderSize); + CertCount = (CertList->SignatureListSize - sizeof (EFI_SIGNATURE_LIST) - CertList->SignatureHeaderSize) / CertList->SignatureSize; + for (Index = 0; Index < CertCount; Index++) { + // + // Iterate each Signature Data Node within this CertList for a verify + // + RootCert = Cert->SignatureData; + RootCertSize = CertList->SignatureSize; + + // + // Call AuthenticodeVerify library to Verify Authenticode struct. + // + VerifyStatus = AuthenticodeVerify ( + PkcsCertData->CertData, + mSecDataDir->Size - sizeof(PkcsCertData->Hdr), + RootCert, + RootCertSize, + mImageDigest, + mImageDigestSize + ); + + if (VerifyStatus) { + goto Done; + } + Cert = (EFI_SIGNATURE_DATA *) ((UINT8 *) Cert + CertList->SignatureSize); + } + } + DataSize -= CertList->SignatureListSize; + CertList = (EFI_SIGNATURE_LIST *) ((UINT8 *) CertList + CertList->SignatureListSize); + } + } + + + + // + // 2: Find certificate from DB database and try to verify authenticode struct. + // + DataSize = 0; + Status = gRT->GetVariable (EFI_IMAGE_SECURITY_DATABASE, &gEfiImageSecurityDatabaseGuid, NULL, &DataSize, NULL); + if (Status == EFI_BUFFER_TOO_SMALL) { + Data = (UINT8 *)AllocateZeroPool (DataSize); + ASSERT (Data != NULL); + + Status = gRT->GetVariable (EFI_IMAGE_SECURITY_DATABASE, &gEfiImageSecurityDatabaseGuid, NULL, &DataSize, (VOID *)Data); + if (EFI_ERROR (Status)) { + goto Done; + } + + // + // Find Cert Enrolled in DB database to verify the signature in pkcs7 signed data. + // + CertList = (EFI_SIGNATURE_LIST *) Data; + while ((DataSize > 0) && (DataSize >= CertList->SignatureListSize)) { + if (CompareGuid (&CertList->SignatureType, &gEfiCertX509Guid)) { + Cert = (EFI_SIGNATURE_DATA *) ((UINT8 *) CertList + sizeof (EFI_SIGNATURE_LIST) + CertList->SignatureHeaderSize); + CertCount = (CertList->SignatureListSize - sizeof (EFI_SIGNATURE_LIST) - CertList->SignatureHeaderSize) / CertList->SignatureSize; + for (Index = 0; Index < CertCount; Index++) { + // + // Iterate each Signature Data Node within this CertList for a verify + // + RootCert = Cert->SignatureData; + RootCertSize = CertList->SignatureSize; + + // + // Call AuthenticodeVerify library to Verify Authenticode struct. + // + VerifyStatus = AuthenticodeVerify ( + PkcsCertData->CertData, + mSecDataDir->Size - sizeof(PkcsCertData->Hdr), + RootCert, + RootCertSize, + mImageDigest, + mImageDigestSize + ); + + if (VerifyStatus) { + goto Done; + } + Cert = (EFI_SIGNATURE_DATA *) ((UINT8 *) Cert + CertList->SignatureSize); + } + } + DataSize -= CertList->SignatureListSize; + CertList = (EFI_SIGNATURE_LIST *) ((UINT8 *) CertList + CertList->SignatureListSize); + } + } + +Done: + if (Data != NULL) { + FreePool (Data); + } + + if (VerifyStatus) { + 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 + +**/ +EFI_STATUS +VerifyCertUefiGuid ( + VOID + ) +{ + BOOLEAN Status; + WIN_CERTIFICATE_UEFI_GUID *EfiCert; + EFI_SIGNATURE_LIST *KekList; + EFI_SIGNATURE_DATA *KekItem; + EFI_CERT_BLOCK_RSA_2048_SHA256 *CertBlock; + VOID *Rsa; + UINTN KekCount; + UINTN Index; + UINTN KekDataSize; + BOOLEAN IsFound; + EFI_STATUS Result; + + EfiCert = NULL; + KekList = NULL; + KekItem = NULL; + CertBlock = NULL; + Rsa = NULL; + Status = FALSE; + IsFound = FALSE; + KekDataSize = 0; + + EfiCert = (WIN_CERTIFICATE_UEFI_GUID *) (mImageBase + mSecDataDir->VirtualAddress); + CertBlock = (EFI_CERT_BLOCK_RSA_2048_SHA256 *) EfiCert->CertData; + if (!CompareGuid (&EfiCert->CertType, &gEfiCertTypeRsa2048Sha256Guid)) { + // + // 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. + // + KekList = GetEfiGlobalVariable (EFI_KEY_EXCHANGE_KEY_NAME); + if (KekList == NULL) { + 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! + // + while ((KekDataSize > 0) && (KekDataSize >= KekList->SignatureListSize)) { + if (CompareGuid (&KekList->SignatureType, &gEfiCertRsa2048Guid)) { + KekItem = (EFI_SIGNATURE_DATA *) ((UINT8 *) KekList + sizeof (EFI_SIGNATURE_LIST) + KekList->SignatureHeaderSize); + KekCount = (KekList->SignatureListSize - sizeof (EFI_SIGNATURE_LIST) - KekList->SignatureHeaderSize) / KekList->SignatureSize; + for (Index = 0; Index < KekCount; Index++) { + if (CompareMem (KekItem->SignatureData, CertBlock->PublicKey, EFI_CERT_TYPE_RSA2048_SIZE) == 0) { + IsFound = TRUE; + break; + } + KekItem = (EFI_SIGNATURE_DATA *) ((UINT8 *) KekItem + KekList->SignatureSize); + } + } + KekDataSize -= KekList->SignatureListSize; + KekList = (EFI_SIGNATURE_LIST *) ((UINT8 *) KekList + KekList->SignatureListSize); + } + + if (!IsFound) { + // + // Signed key is not a trust one. + // + goto Done; + } + + // + // Now, we found the corresponding security policy. + // Verify the data payload. + // + Rsa = RsaNew (); + ASSERT (Rsa != NULL); + // + // Set RSA Key Components. + // NOTE: Only N and E are needed to be set as RSA public key for signature verification. + // + Status = RsaSetKey (Rsa, RsaKeyN, CertBlock->PublicKey, EFI_CERT_TYPE_RSA2048_SIZE); + if (!Status) { + goto Done; + } + Status = RsaSetKey (Rsa, RsaKeyE, mRsaE, sizeof (mRsaE)); + if (!Status) { + goto Done; + } + // + // Verify the signature. + // + Status = RsaPkcs1Verify ( + Rsa, + mImageDigest, + mImageDigestSize, + CertBlock->Signature, + EFI_CERT_TYPE_RSA2048_SHA256_SIZE + ); + +Done: + if (KekList != NULL) { + FreePool (KekList); + } + if (Rsa != NULL ) { + RsaFree (Rsa); + } + 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. + + @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 File is NULL. + @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. + +**/ +EFI_STATUS +EFIAPI +DxeImageVerificationHandler ( + IN UINT32 AuthenticationStatus, + IN CONST EFI_DEVICE_PATH_PROTOCOL *File, + IN VOID *FileBuffer, + IN UINTN FileSize + ) + +{ + EFI_STATUS Status; + UINT16 Magic; + EFI_IMAGE_DOS_HEADER *DosHdr; + EFI_STATUS VerifyStatus; + UINT8 *SetupMode; + EFI_SIGNATURE_LIST *SignatureList; + UINTN SignatureListSize; + EFI_SIGNATURE_DATA *Signature; + EFI_IMAGE_EXECUTION_ACTION Action; + WIN_CERTIFICATE *WinCertificate; + UINT32 Policy; + + if (File == NULL) { + return EFI_INVALID_PARAMETER; + } + + SignatureList = NULL; + SignatureListSize = 0; + WinCertificate = NULL; + Action = EFI_IMAGE_EXECUTION_AUTH_UNTESTED; + Status = EFI_ACCESS_DENIED; + // + // Check the image type and get policy setting. + // + switch (GetImageType (File)) { + + case IMAGE_FROM_FV: + Policy = ALWAYS_EXECUTE; + break; + + case IMAGE_FROM_OPTION_ROM: + Policy = PcdGet32 (PcdOptionRomImageVerificationPolicy); + break; + + case IMAGE_FROM_REMOVABLE_MEDIA: + Policy = PcdGet32 (PcdRemovableMediaImageVerificationPolicy); + break; + + case IMAGE_FROM_FIXED_MEDIA: + Policy = PcdGet32 (PcdFixedMediaImageVerificationPolicy); + break; + + default: + Policy = DENY_EXECUTE_ON_SECURITY_VIOLATION; + break; + } + // + // If policy is always/never execute, return directly. + // + if (Policy == ALWAYS_EXECUTE) { + return EFI_SUCCESS; + } else if (Policy == NEVER_EXECUTE) { + return EFI_ACCESS_DENIED; + } + SetupMode = GetEfiGlobalVariable (EFI_SETUP_MODE_NAME); + + // + // SetupMode doesn't exist means no AuthVar driver is dispatched, + // skip verification. + // + if (SetupMode == NULL) { + return EFI_SUCCESS; + } + + // + // If platform is in SETUP MODE, skip verification. + // + if (*SetupMode == SETUP_MODE) { + FreePool (SetupMode); + return EFI_SUCCESS; + } + // + // Read the Dos header. + // + ASSERT (FileBuffer != NULL); + mImageBase = (UINT8 *) FileBuffer; + mImageSize = FileSize; + DosHdr = (EFI_IMAGE_DOS_HEADER *) (mImageBase); + if (DosHdr->e_magic == EFI_IMAGE_DOS_SIGNATURE) { + // + // DOS image header is present, + // so read the PE header after the DOS image header. + // + mPeCoffHeaderOffset = DosHdr->e_lfanew; + } else { + mPeCoffHeaderOffset = 0; + } + // + // Check PE/COFF image. + // + mNtHeader.Pe32 = (EFI_IMAGE_NT_HEADERS32 *) (mImageBase + mPeCoffHeaderOffset); + if (mNtHeader.Pe32->Signature != EFI_IMAGE_NT_SIGNATURE) { + // + // It is not a valid Pe/Coff file. + // + return EFI_ACCESS_DENIED; + } + + Magic = mNtHeader.Pe32->OptionalHeader.Magic; + 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]; + } + + if (mSecDataDir->Size == 0) { + // + // This image is not signed. + // + Action = EFI_IMAGE_EXECUTION_AUTH_UNTESTED; + Status = EFI_ACCESS_DENIED; + goto Done; + } + // + // Verify signature of executables. + // + WinCertificate = (WIN_CERTIFICATE *) (mImageBase + mSecDataDir->VirtualAddress); + + switch (WinCertificate->wCertificateType) { + + case WIN_CERT_TYPE_EFI_GUID: + // + // Verify UEFI GUID type. + // + if (!HashPeImage (HASHALG_SHA256)) { + goto Done; + } + + VerifyStatus = VerifyCertUefiGuid (); + break; + + case WIN_CERT_TYPE_PKCS_SIGNED_DATA: + // + // Verify Pkcs signed data type. + // + Status = HashPeImageByType(); + if (EFI_ERROR(Status)) { + goto Done; + } + + VerifyStatus = VerifyCertPkcsSignedData (); + + // + // For image verification against enrolled certificate(root or intermediate), + // no need to check image's hash in the allowed database. + // + if (!EFI_ERROR (VerifyStatus)) { + return EFI_SUCCESS; + } + + default: + return EFI_ACCESS_DENIED; + } + // + // Get image hash value as executable's signature. + // + SignatureListSize = sizeof (EFI_SIGNATURE_LIST) + sizeof (EFI_SIGNATURE_DATA) - 1 + mImageDigestSize; + SignatureList = (EFI_SIGNATURE_LIST *) AllocateZeroPool (SignatureListSize); + ASSERT (SignatureList != NULL); + SignatureList->SignatureHeaderSize = 0; + SignatureList->SignatureListSize = (UINT32) SignatureListSize; + SignatureList->SignatureSize = (UINT32) mImageDigestSize; + CopyMem (&SignatureList->SignatureType, &mCertType, sizeof (EFI_GUID)); + Signature = (EFI_SIGNATURE_DATA *) ((UINT8 *) SignatureList + sizeof (EFI_SIGNATURE_LIST)); + CopyMem (Signature->SignatureData, mImageDigest, mImageDigestSize); + // + // Signature database check after verification. + // + if (EFI_ERROR (VerifyStatus)) { + // + // Verification failure. + // + Action = EFI_IMAGE_EXECUTION_AUTH_SIG_FAILED; + Status = EFI_ACCESS_DENIED; + } else if (IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE1, Signature->SignatureData, &mCertType, mImageDigestSize)) { + // + // Executable signature verification passes, but is found in forbidden signature database. + // + Action = EFI_IMAGE_EXECUTION_AUTH_SIG_FOUND; + Status = EFI_ACCESS_DENIED; + } else if (IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE, Signature->SignatureData, &mCertType, mImageDigestSize)) { + // + // Executable signature is found in authorized signature database. + // + Status = EFI_SUCCESS; + } else { + // + // Executable signature verification passes, but cannot be found in authorized signature database. + // Get platform policy to determine the action. + // + Action = EFI_IMAGE_EXECUTION_AUTH_SIG_PASSED; + Status = ImageAuthorization (Policy); + } + +Done: + if (Status != EFI_SUCCESS) { + // + // Policy decides to defer or reject the image; add its information in image executable information table. + // + AddImageExeInfo (Action, NULL, File, SignatureList, SignatureListSize); + } + + if (SignatureList != NULL) { + FreePool (SignatureList); + } + + FreePool (SetupMode); + + 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. + +**/ +VOID +EFIAPI +VariableWriteCallBack ( + IN EFI_EVENT Event, + IN VOID *Context + ) +{ + UINT8 SecureBootMode; + UINT8 *SecureBootModePtr; + EFI_STATUS Status; + VOID *ProtocolPointer; + + Status = gBS->LocateProtocol (&gEfiVariableWriteArchProtocolGuid, NULL, &ProtocolPointer); + if (EFI_ERROR (Status)) { + return; + } + + // + // Check whether "SecureBoot" variable exists. + // If this library is built-in, it means firmware has capability to perform + // driver signing verification. + // + SecureBootModePtr = GetEfiGlobalVariable (EFI_SECURE_BOOT_MODE_NAME); + if (SecureBootModePtr == NULL) { + SecureBootMode = SECURE_BOOT_MODE_DISABLE; + // + // Authenticated variable driver will update "SecureBoot" depending on SetupMode variable. + // + gRT->SetVariable ( + EFI_SECURE_BOOT_MODE_NAME, + &gEfiGlobalVariableGuid, + EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_NON_VOLATILE, + sizeof (UINT8), + &SecureBootMode + ); + } else { + FreePool (SecureBootModePtr); + } +} + +/** + 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. +**/ +EFI_STATUS +EFIAPI +DxeImageVerificationLibConstructor ( + IN EFI_HANDLE ImageHandle, + IN EFI_SYSTEM_TABLE *SystemTable + ) +{ + VOID *Registration; + + // + // Register callback function upon VariableWriteArchProtocol. + // + EfiCreateProtocolNotifyEvent ( + &gEfiVariableWriteArchProtocolGuid, + TPL_CALLBACK, + VariableWriteCallBack, + NULL, + &Registration + ); + + return RegisterSecurityHandler ( + DxeImageVerificationHandler, + EFI_AUTH_OPERATION_VERIFY_IMAGE | EFI_AUTH_OPERATION_IMAGE_REQUIRED + ); +} -- cgit v1.2.3