X-Git-Url: https://git.proxmox.com/?p=mirror_edk2.git;a=blobdiff_plain;f=SecurityPkg%2FLibrary%2FDxeImageVerificationLib%2FDxeImageVerificationLib.c;h=402540eb1b2bd4469f42bffcc5b6975537848ea5;hp=148dbd5a89e9dd56e4bfca5a9c6af7b701824c4b;hb=bc2dfdbcfc11dc785f0cc0ad2f519a63b98f88bc;hpb=0c18794ea4289f03fefc7117b56740414cc0536c diff --git a/SecurityPkg/Library/DxeImageVerificationLib/DxeImageVerificationLib.c b/SecurityPkg/Library/DxeImageVerificationLib/DxeImageVerificationLib.c index 148dbd5a89..402540eb1b 100644 --- a/SecurityPkg/Library/DxeImageVerificationLib/DxeImageVerificationLib.c +++ b/SecurityPkg/Library/DxeImageVerificationLib/DxeImageVerificationLib.c @@ -1,27 +1,46 @@ /** @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 + 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 - 2012, 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, +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" +// +// 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_IMAGE_DATA_DIRECTORY *mSecDataDir = NULL; +EFI_GUID mCertType; + +// +// Information on current PE/COFF image +// UINTN mImageSize; -UINT32 mPeCoffHeaderOffset; +UINT8 *mImageBase = NULL; UINT8 mImageDigest[MAX_DIGEST_SIZE]; UINTN mImageDigestSize; -EFI_IMAGE_DATA_DIRECTORY *mSecDataDir = NULL; -UINT8 *mImageBase = NULL; -EFI_GUID mCertType; // // Notify string for authorization UI. @@ -54,14 +73,62 @@ HASH_TABLE mHash[] = { { L"SHA512", 64, &mHashOidValue[40], 9, NULL, NULL, NULL, NULL } }; +/** + 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. + being dispatched. - @return UINT32 Image Type + @return UINT32 Image Type **/ UINT32 @@ -70,7 +137,7 @@ GetImageType ( ) { EFI_STATUS Status; - EFI_HANDLE DeviceHandle; + EFI_HANDLE DeviceHandle; EFI_DEVICE_PATH_PROTOCOL *TempDevicePath; EFI_BLOCK_IO_PROTOCOL *BlockIo; @@ -78,7 +145,7 @@ GetImageType ( // First check to see if File is from a Firmware Volume // DeviceHandle = NULL; - TempDevicePath = (EFI_DEVICE_PATH_PROTOCOL *)File; + TempDevicePath = (EFI_DEVICE_PATH_PROTOCOL *) File; Status = gBS->LocateDevicePath ( &gEfiFirmwareVolume2ProtocolGuid, &TempDevicePath, @@ -102,7 +169,7 @@ GetImageType ( // Next check to see if File is from a Block I/O device // DeviceHandle = NULL; - TempDevicePath = (EFI_DEVICE_PATH_PROTOCOL *)File; + TempDevicePath = (EFI_DEVICE_PATH_PROTOCOL *) File; Status = gBS->LocateDevicePath ( &gEfiBlockIoProtocolGuid, &TempDevicePath, @@ -136,11 +203,11 @@ GetImageType ( } // - // File is not in a Firmware Volume or on a Block I/O device, so check to see if + // 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; + TempDevicePath = (EFI_DEVICE_PATH_PROTOCOL *) File; Status = gBS->LocateDevicePath ( &gEfiSimpleFileSystemProtocolGuid, &TempDevicePath, @@ -155,12 +222,12 @@ GetImageType ( // // 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. + // 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; + 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; @@ -170,7 +237,7 @@ GetImageType ( case MESSAGING_DEVICE_PATH: if (DevicePathSubType(TempDevicePath) == MSG_MAC_ADDR_DP) { return IMAGE_FROM_REMOVABLE_MEDIA; - } + } break; default: @@ -178,20 +245,24 @@ GetImageType ( } TempDevicePath = NextDevicePathNode (TempDevicePath); } - return IMAGE_UNKNOWN; + return IMAGE_UNKNOWN; } /** Caculate 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] HashAlg Hash algorithm type. - + @retval TRUE Successfully hash image. @retval FALSE Fail in hash image. **/ -BOOLEAN +BOOLEAN HashPeImage ( IN UINT32 HashAlg ) @@ -207,6 +278,8 @@ HashPeImage ( EFI_IMAGE_SECTION_HEADER *SectionHeader; UINTN Index; UINTN Pos; + UINT32 CertSize; + UINT32 NumberOfRvaAndSizes; HashCtx = NULL; SectionHeader = NULL; @@ -215,7 +288,7 @@ HashPeImage ( if ((HashAlg != HASHALG_SHA1) && (HashAlg != HASHALG_SHA256)) { return FALSE; } - + // // Initialize context of hash. // @@ -232,23 +305,40 @@ HashPeImage ( } CtxSize = mHash[HashAlg].GetContextSize(); - + HashCtx = AllocatePool (CtxSize); - ASSERT (HashCtx != NULL); + 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 // - Magic = mNtHeader.Pe32->OptionalHeader.Magic; + if (mNtHeader.Pe32->FileHeader.Machine == IMAGE_FILE_MACHINE_IA64 && mNtHeader.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) { + // + // NOTE: Some versions of Linux ELILO for Itanium have an incorrect magic value + // in the PE/COFF Header. If the MachineType is Itanium(IA64) and the + // Magic value in the OptionalHeader is EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC + // then override the magic value to EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC + // + Magic = EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC; + } else { + // + // Get the magic value from the PE/COFF Optional Header + // + 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. @@ -259,62 +349,105 @@ HashPeImage ( // Use PE32 offset. // HashSize = (UINTN) ((UINT8 *) (&mNtHeader.Pe32->OptionalHeader.CheckSum) - HashBase); - } else { + NumberOfRvaAndSizes = mNtHeader.Pe32->OptionalHeader.NumberOfRvaAndSizes; + } else if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC) { // // Use PE32+ offset. // HashSize = (UINTN) ((UINT8 *) (&mNtHeader.Pe32Plus->OptionalHeader.CheckSum) - 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). - // 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) { + if (NumberOfRvaAndSizes <= EFI_IMAGE_DIRECTORY_ENTRY_SECURITY) { // - // Use PE32 offset. + // 6. Since there is no Cert Directory in optional header, hash everything + // from the end of the checksum to the end of image header. // - 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); - } + if (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 - mImageBase); + } else { + // + // Use PE32+ offset. + // + HashBase = (UINT8 *) &mNtHeader.Pe32Plus->OptionalHeader.CheckSum + sizeof (UINT32); + HashSize = mNtHeader.Pe32Plus->OptionalHeader.SizeOfHeaders - (UINTN) (HashBase - mImageBase); + } - 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) { + if (HashSize != 0) { + Status = mHash[HashAlg].HashUpdate(HashCtx, HashBase, HashSize); + if (!Status) { + goto Done; + } + } + } else { // - // Use PE32 offset + // 7. Hash everything from the end of the checksum to the start of the Cert Directory. // - 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 { + 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); + } + + if (HashSize != 0) { + Status = mHash[HashAlg].HashUpdate(HashCtx, HashBase, HashSize); + if (!Status) { + goto Done; + } + } + // - // Use PE32+ offset. + // 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. // - 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); - } + 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) (HashBase - mImageBase); + } else { + // + // Use PE32+ offset. + // + HashBase = (UINT8 *) &mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY + 1]; + HashSize = mNtHeader.Pe32Plus->OptionalHeader.SizeOfHeaders - (UINTN) (HashBase - mImageBase); + } - Status = mHash[HashAlg].HashUpdate(HashCtx, HashBase, HashSize); - if (!Status) { - goto Done; + 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. // @@ -330,6 +463,15 @@ HashPeImage ( 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 @@ -337,20 +479,16 @@ HashPeImage ( // 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); + 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. // - 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)) { @@ -392,29 +530,36 @@ HashPeImage ( // 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); + + if (NumberOfRvaAndSizes <= EFI_IMAGE_DIRECTORY_ENTRY_SECURITY) { + CertSize = 0; } else { - // - // Use PE32+ offset. - // - HashSize = (UINTN)( - mImageSize - - mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY].Size - - SumOfBytesHashed); + if (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; + } } - Status = mHash[HashAlg].HashUpdate(HashCtx, HashBase, HashSize); - if (!Status) { + 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: @@ -428,15 +573,19 @@ Done: } /** - 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 + 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 + 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. + @retval EFI_UNSUPPORTED Hash algorithm is not supported. @retval EFI_SUCCESS Hash successfully. **/ -EFI_STATUS +EFI_STATUS HashPeImageByType ( VOID ) @@ -446,10 +595,14 @@ HashPeImageByType ( PkcsCertData = (WIN_CERTIFICATE_EFI_PKCS *) (mImageBase + mSecDataDir->VirtualAddress); - for (Index = 0; Index < HASHALG_MAX; Index++) { + if (PkcsCertData->Hdr.dwLength < sizeof (WIN_CERTIFICATE_EFI_PKCS) + 32) { + return EFI_UNSUPPORTED; + } + + for (Index = 0; Index < HASHALG_MAX; Index++) { // // Check the Hash algorithm in PE/COFF Authenticode. - // According to PKCS#7 Definition: + // According to PKCS#7 Definition: // SignedData ::= SEQUENCE { // version Version, // digestAlgorithms DigestAlgorithmIdentifiers, @@ -457,7 +610,19 @@ HashPeImageByType ( // .... } // 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 ((*(PkcsCertData->CertData + 1) & TWO_BYTE_ENCODE) != TWO_BYTE_ENCODE) { + // + // Only support two bytes of Long Form of Length Encoding. + // + continue; + } + + if (PkcsCertData->Hdr.dwLength < sizeof (WIN_CERTIFICATE_EFI_PKCS) + 32 + mHash[Index].OidLength) { + return EFI_UNSUPPORTED; + } + if (CompareMem (PkcsCertData->CertData + 32, mHash[Index].OidValue, mHash[Index].OidLength) == 0) { break; } @@ -485,7 +650,7 @@ HashPeImageByType ( 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. @@ -521,18 +686,17 @@ GetImageExeInfoTableSize ( @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 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; @@ -541,18 +705,21 @@ AddImageExeInfo ( UINTN NameStringLen; UINTN DevicePathSize; - ASSERT (DevicePath != NULL); ImageExeInfoTable = NULL; NewImageExeInfoTable = NULL; ImageExeInfoEntry = NULL; NameStringLen = 0; + if (DevicePath == NULL) { + return ; + } + if (Name != NULL) { NameStringLen = StrSize (Name); } ImageExeInfoTable = NULL; - EfiGetSystemConfigurationTable (&gEfiImageSecurityDatabaseGuid, (VOID**)&ImageExeInfoTable); + EfiGetSystemConfigurationTable (&gEfiImageSecurityDatabaseGuid, (VOID **) &ImageExeInfoTable); if (ImageExeInfoTable != NULL) { // // The table has been found! @@ -570,7 +737,9 @@ AddImageExeInfo ( 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 (NewImageExeInfoTable == NULL) { + return ; + } if (ImageExeInfoTable != NULL) { CopyMem (NewImageExeInfoTable, ImageExeInfoTable, ImageExeInfoTableSize); @@ -603,8 +772,8 @@ AddImageExeInfo ( // // Update/replace the image execution table. // - Status = gBS->InstallConfigurationTable (&gEfiImageSecurityDatabaseGuid, (VOID *) NewImageExeInfoTable); - ASSERT_EFI_ERROR (Status); + gBS->InstallConfigurationTable (&gEfiImageSecurityDatabaseGuid, (VOID *) NewImageExeInfoTable); + // // Free Old table data! // @@ -613,60 +782,6 @@ AddImageExeInfo ( } } -/** - 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. @@ -682,7 +797,7 @@ ImageAuthorization ( BOOLEAN IsSignatureFoundInDatabase ( IN CHAR16 *VariableName, - IN UINT8 *Signature, + IN UINT8 *Signature, IN EFI_GUID *CertType, IN UINTN SignatureSize ) @@ -707,7 +822,9 @@ IsSignatureFoundInDatabase ( } Data = (UINT8 *) AllocateZeroPool (DataSize); - ASSERT (Data != NULL); + if (Data == NULL) { + return FALSE; + } Status = gRT->GetVariable (VariableName, &gEfiImageSecurityDatabaseGuid, NULL, &DataSize, Data); if (EFI_ERROR (Status)) { @@ -751,16 +868,20 @@ Done: } /** - Verify certificate in WIN_CERT_TYPE_PKCS_SIGNED_DATA format . + Verify PKCS#7 SignedData using certificate found in Variable which formatted + as EFI_SIGNATURE_LIST. The Variable may be PK, KEK, DB or DBX. - @retval EFI_SUCCESS Image pass verification. - @retval EFI_SECURITY_VIOLATION Image fail verification. - @retval other error value + @param VariableName Name of Variable to search for Certificate. + @param VendorGuid Variable vendor GUID. + + @retval TRUE Image pass verification. + @retval FALSE Image fail verification. **/ -EFI_STATUS -VerifyCertPkcsSignedData ( - VOID +BOOLEAN +IsPkcsSignedDataVerifiedBySignatureList ( + IN CHAR16 *VariableName, + IN EFI_GUID *VendorGuid ) { EFI_STATUS Status; @@ -775,85 +896,30 @@ VerifyCertPkcsSignedData ( UINTN Index; UINTN CertCount; - Data = NULL; - CertList = NULL; - Cert = NULL; - RootCert = NULL; - RootCertSize = 0; - VerifyStatus = FALSE; - PkcsCertData = (WIN_CERTIFICATE_EFI_PKCS *) (mImageBase + mSecDataDir->VirtualAddress); + 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); + Status = gRT->GetVariable (VariableName, VendorGuid, 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; + Data = (UINT8 *) AllocateZeroPool (DataSize); + if (Data == NULL) { + return VerifyStatus; } - - // - // 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); + Status = gRT->GetVariable (VariableName, VendorGuid, NULL, &DataSize, (VOID *) Data); if (EFI_ERROR (Status)) { goto Done; } // - // Find Cert Enrolled in DB database to verify the signature in pkcs7 signed data. - // + // Find X509 certificate in Signature List to verify the signature in pkcs7 signed data. + // CertList = (EFI_SIGNATURE_LIST *) Data; while ((DataSize > 0) && (DataSize >= CertList->SignatureListSize)) { if (CompareGuid (&CertList->SignatureType, &gEfiCertX509Guid)) { @@ -861,28 +927,27 @@ VerifyCertPkcsSignedData ( 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 - // + // Iterate each Signature Data Node within this CertList for verify. + // RootCert = Cert->SignatureData; - RootCertSize = CertList->SignatureSize; - + RootCertSize = CertList->SignatureSize - sizeof (EFI_GUID); + // - // Call AuthenticodeVerify library to Verify Authenticode struct. + // Call AuthenticodeVerify library to Verify Authenticode struct. // VerifyStatus = AuthenticodeVerify ( PkcsCertData->CertData, - mSecDataDir->Size - sizeof(PkcsCertData->Hdr), + PkcsCertData->Hdr.dwLength - 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); @@ -894,136 +959,36 @@ Done: FreePool (Data); } - if (VerifyStatus) { - return EFI_SUCCESS; - } else { - return EFI_SECURITY_VIOLATION; - } + return VerifyStatus; } /** - Verify certificate in WIN_CERTIFICATE_UEFI_GUID format. + 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 -VerifyCertUefiGuid ( +EFI_STATUS +VerifyCertPkcsSignedData ( 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 + // 1: Find certificate from DBX forbidden database for revoked certificate. // - 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) { + if (IsPkcsSignedDataVerifiedBySignatureList (EFI_IMAGE_SECURITY_DATABASE1, &gEfiImageSecurityDatabaseGuid)) { // - // Signed key is not a trust one. + // DBX is forbidden database, if Authenticode verification pass with + // one of the certificate in DBX, this image should be rejected. // - goto Done; + return EFI_SECURITY_VIOLATION; } // - // 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. + // 2: Find certificate from DB database and try to verify authenticode struct. // - 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) { + if (IsPkcsSignedDataVerifiedBySignatureList (EFI_IMAGE_SECURITY_DATABASE, &gEfiImageSecurityDatabaseGuid)) { return EFI_SUCCESS; } else { return EFI_SECURITY_VIOLATION; @@ -1032,13 +997,37 @@ Done: /** 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 + 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 + 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: + If the image is signed, + If the image's certificate verifies against a certificate (root or intermediate) in the allowed + database (DB) and not in the forbidden database (DBX), the certificate verification is passed. + If the image's hash digest is in DBX, + deny execution. + If not, + run it. + If the Image's certificate verification failed. + If the Image's Hash is in DB and not in DBX, + run it. + Otherwise, + deny execution. + Otherwise, the image is not signed, + Is the Image's Hash in DBX? + If yes, deny execution. + If not, is the Image's Hash in DB? + If yes, run it. + If not, deny execution. + + 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] 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 @@ -1048,7 +1037,8 @@ Done: @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_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 @@ -1067,19 +1057,21 @@ DxeImageVerificationHandler ( 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; + EFI_STATUS Status; + UINT16 Magic; + EFI_IMAGE_DOS_HEADER *DosHdr; + EFI_STATUS VerifyStatus; + EFI_SIGNATURE_LIST *SignatureList; + UINTN SignatureListSize; + EFI_SIGNATURE_DATA *Signature; + EFI_IMAGE_EXECUTION_ACTION Action; + WIN_CERTIFICATE *WinCertificate; + UINT32 Policy; + UINT8 *SecureBoot; + PE_COFF_LOADER_IMAGE_CONTEXT ImageContext; + UINT32 NumberOfRvaAndSizes; + UINT32 CertSize; if (File == NULL) { return EFI_INVALID_PARAMETER; @@ -1094,7 +1086,7 @@ DxeImageVerificationHandler ( // Check the image type and get policy setting. // switch (GetImageType (File)) { - + case IMAGE_FROM_FV: Policy = ALWAYS_EXECUTE; break; @@ -1112,7 +1104,7 @@ DxeImageVerificationHandler ( break; default: - Policy = DENY_EXECUTE_ON_SECURITY_VIOLATION; + Policy = DENY_EXECUTE_ON_SECURITY_VIOLATION; break; } // @@ -1123,33 +1115,55 @@ DxeImageVerificationHandler ( } else if (Policy == NEVER_EXECUTE) { return EFI_ACCESS_DENIED; } - SetupMode = GetEfiGlobalVariable (EFI_SETUP_MODE_NAME); + GetEfiGlobalVariable2 (EFI_SECURE_BOOT_MODE_NAME, (VOID**)&SecureBoot, NULL); // - // SetupMode doesn't exist means no AuthVar driver is dispatched, - // skip verification. + // Skip verification if SecureBoot variable doesn't exist. // - if (SetupMode == NULL) { + if (SecureBoot == NULL) { return EFI_SUCCESS; } // - // If platform is in SETUP MODE, skip verification. + // Skip verification if SecureBoot is disabled. // - if (*SetupMode == SETUP_MODE) { - FreePool (SetupMode); + if (*SecureBoot == SECURE_BOOT_MODE_DISABLE) { + FreePool (SecureBoot); return EFI_SUCCESS; } + FreePool (SecureBoot); + // // Read the Dos header. // - ASSERT (FileBuffer != NULL); + if (FileBuffer == NULL) { + return EFI_INVALID_PARAMETER; + } + mImageBase = (UINT8 *) FileBuffer; mImageSize = FileSize; - DosHdr = (EFI_IMAGE_DOS_HEADER *) (mImageBase); + + ZeroMem (&ImageContext, sizeof (ImageContext)); + ImageContext.Handle = (VOID *) FileBuffer; + ImageContext.ImageRead = (PE_COFF_LOADER_READ_FILE) DxeImageVerificationLibImageRead; + + // + // Get information about the image being loaded + // + Status = PeCoffLoaderGetImageInfo (&ImageContext); + if (EFI_ERROR (Status)) { + // + // The information can't be got from the invalid PeImage + // + goto Done; + } + + Status = EFI_ACCESS_DENIED; + + DosHdr = (EFI_IMAGE_DOS_HEADER *) mImageBase; if (DosHdr->e_magic == EFI_IMAGE_DOS_SIGNATURE) { // - // DOS image header is present, + // DOS image header is present, // so read the PE header after the DOS image header. // mPeCoffHeaderOffset = DosHdr->e_lfanew; @@ -1164,109 +1178,146 @@ DxeImageVerificationHandler ( // // It is not a valid Pe/Coff file. // - return EFI_ACCESS_DENIED; + goto Done; } - Magic = mNtHeader.Pe32->OptionalHeader.Magic; + if (mNtHeader.Pe32->FileHeader.Machine == IMAGE_FILE_MACHINE_IA64 && mNtHeader.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) { + // + // NOTE: Some versions of Linux ELILO for Itanium have an incorrect magic value + // in the PE/COFF Header. If the MachineType is Itanium(IA64) and the + // Magic value in the OptionalHeader is EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC + // then override the magic value to EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC + // + Magic = EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC; + } else { + // + // Get the magic value from the PE/COFF Optional Header + // + 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]; + NumberOfRvaAndSizes = mNtHeader.Pe32->OptionalHeader.NumberOfRvaAndSizes; + if (NumberOfRvaAndSizes > EFI_IMAGE_DIRECTORY_ENTRY_SECURITY) { + 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]; + NumberOfRvaAndSizes = mNtHeader.Pe32Plus->OptionalHeader.NumberOfRvaAndSizes; + if (NumberOfRvaAndSizes > EFI_IMAGE_DIRECTORY_ENTRY_SECURITY) { + mSecDataDir = (EFI_IMAGE_DATA_DIRECTORY *) &mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY]; + } } - if (mSecDataDir->Size == 0) { + if ((mSecDataDir == NULL) || ((mSecDataDir != NULL) && (mSecDataDir->Size == 0))) { // // This image is not signed. // - Action = EFI_IMAGE_EXECUTION_AUTH_UNTESTED; - Status = EFI_ACCESS_DENIED; - goto Done; + 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. // 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; - } + CertSize = sizeof (WIN_CERTIFICATE); - VerifyStatus = VerifyCertUefiGuid (); - break; + if ((mSecDataDir->Size <= CertSize) || (mSecDataDir->Size < WinCertificate->dwLength)) { + goto Done; + } - case WIN_CERT_TYPE_PKCS_SIGNED_DATA: + if (WinCertificate->wCertificateType == WIN_CERT_TYPE_PKCS_SIGNED_DATA) { // // Verify Pkcs signed data type. // - Status = HashPeImageByType(); - if (EFI_ERROR(Status)) { + Status = HashPeImageByType(); + if (EFI_ERROR (Status)) { goto Done; } - + VerifyStatus = VerifyCertPkcsSignedData (); + } else { + goto Done; + } + if (!EFI_ERROR (VerifyStatus)) { // - // For image verification against enrolled certificate(root or intermediate), - // no need to check image's hash in the allowed database. + // Verification is passed. + // Continue to check the image digest in signature database. // - if (!EFI_ERROR (VerifyStatus)) { + if (IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE1, mImageDigest, &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 { + // + // For image verification against enrolled X.509 certificate(root or intermediate), + // no need to check image's hash in the allowed database. + // 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)) { + } else { // // 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 { + 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). + // + Status = EFI_SUCCESS; + } else { + Action = EFI_IMAGE_EXECUTION_AUTH_SIG_FAILED; + Status = EFI_ACCESS_DENIED; + } + } + + if (EFI_ERROR (Status)) { // - // Executable signature verification passes, but cannot be found in authorized signature database. - // Get platform policy to determine the action. + // Get image hash value as executable's signature. // - Action = EFI_IMAGE_EXECUTION_AUTH_SIG_PASSED; - Status = ImageAuthorization (Policy); + SignatureListSize = sizeof (EFI_SIGNATURE_LIST) + sizeof (EFI_SIGNATURE_DATA) - 1 + mImageDigestSize; + SignatureList = (EFI_SIGNATURE_LIST *) AllocateZeroPool (SignatureListSize); + if (SignatureList == NULL) { + Status = EFI_OUT_OF_RESOURCES; + goto Done; + } + 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); } Done: @@ -1281,17 +1332,15 @@ Done: 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 @@ -1309,13 +1358,13 @@ VariableWriteCallBack ( 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); + GetEfiGlobalVariable2 (EFI_SECURE_BOOT_MODE_NAME, (VOID**)&SecureBootModePtr, NULL); if (SecureBootModePtr == NULL) { SecureBootMode = SECURE_BOOT_MODE_DISABLE; // @@ -1331,7 +1380,7 @@ VariableWriteCallBack ( } else { FreePool (SecureBootModePtr); } -} +} /** Register security measurement handler. @@ -1352,7 +1401,7 @@ DxeImageVerificationLibConstructor ( // // Register callback function upon VariableWriteArchProtocol. - // + // EfiCreateProtocolNotifyEvent ( &gEfiVariableWriteArchProtocolGuid, TPL_CALLBACK, @@ -1364,5 +1413,5 @@ DxeImageVerificationLibConstructor ( return RegisterSecurityHandler ( DxeImageVerificationHandler, EFI_AUTH_OPERATION_VERIFY_IMAGE | EFI_AUTH_OPERATION_IMAGE_REQUIRED - ); + ); }