2 Implement image verification services for secure boot service
4 Caution: This file requires additional review when modified.
5 This library will have external input - PE/COFF image.
6 This external input must be validated carefully to avoid security issue like
7 buffer overflow, integer overflow.
9 DxeImageVerificationLibImageRead() function will make sure the PE/COFF image content
10 read is within the image buffer.
12 DxeImageVerificationHandler(), HashPeImageByType(), HashPeImage() function will accept
13 untrusted PE/COFF image and validate its data structure within this image buffer before use.
15 Copyright (c) 2009 - 2018, Intel Corporation. All rights reserved.<BR>
16 (C) Copyright 2016 Hewlett Packard Enterprise Development LP<BR>
17 SPDX-License-Identifier: BSD-2-Clause-Patent
21 #include "DxeImageVerificationLib.h"
24 // Caution: This is used by a function which may receive untrusted input.
25 // These global variables hold PE/COFF image data, and they should be validated before use.
27 EFI_IMAGE_OPTIONAL_HEADER_PTR_UNION mNtHeader
;
28 UINT32 mPeCoffHeaderOffset
;
32 // Information on current PE/COFF image
35 UINT8
*mImageBase
= NULL
;
36 UINT8 mImageDigest
[MAX_DIGEST_SIZE
];
37 UINTN mImageDigestSize
;
40 // Notify string for authorization UI.
42 CHAR16 mNotifyString1
[MAX_NOTIFY_STRING_LEN
] = L
"Image verification pass but not found in authorized database!";
43 CHAR16 mNotifyString2
[MAX_NOTIFY_STRING_LEN
] = L
"Launch this image anyway? (Yes/Defer/No)";
45 // Public Exponent of RSA Key.
47 CONST UINT8 mRsaE
[] = { 0x01, 0x00, 0x01 };
51 // OID ASN.1 Value for Hash Algorithms
53 UINT8 mHashOidValue
[] = {
54 0x2B, 0x0E, 0x03, 0x02, 0x1A, // OBJ_sha1
55 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04, // OBJ_sha224
56 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, // OBJ_sha256
57 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02, // OBJ_sha384
58 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, // OBJ_sha512
61 HASH_TABLE mHash
[] = {
62 { L
"SHA1", 20, &mHashOidValue
[0], 5, Sha1GetContextSize
, Sha1Init
, Sha1Update
, Sha1Final
},
63 { L
"SHA224", 28, &mHashOidValue
[5], 9, NULL
, NULL
, NULL
, NULL
},
64 { L
"SHA256", 32, &mHashOidValue
[14], 9, Sha256GetContextSize
, Sha256Init
, Sha256Update
, Sha256Final
},
65 { L
"SHA384", 48, &mHashOidValue
[23], 9, Sha384GetContextSize
, Sha384Init
, Sha384Update
, Sha384Final
},
66 { L
"SHA512", 64, &mHashOidValue
[32], 9, Sha512GetContextSize
, Sha512Init
, Sha512Update
, Sha512Final
}
69 EFI_STRING mHashTypeStr
;
72 SecureBoot Hook for processing image verification.
74 @param[in] VariableName Name of Variable to be found.
75 @param[in] VendorGuid Variable vendor GUID.
76 @param[in] DataSize Size of Data found. If size is less than the
77 data, this value contains the required size.
78 @param[in] Data Data pointer.
84 IN CHAR16
*VariableName
,
85 IN EFI_GUID
*VendorGuid
,
91 Reads contents of a PE/COFF image in memory buffer.
93 Caution: This function may receive untrusted input.
94 PE/COFF image is external input, so this function will make sure the PE/COFF image content
95 read is within the image buffer.
97 @param FileHandle Pointer to the file handle to read the PE/COFF image.
98 @param FileOffset Offset into the PE/COFF image to begin the read operation.
99 @param ReadSize On input, the size in bytes of the requested read operation.
100 On output, the number of bytes actually read.
101 @param Buffer Output buffer that contains the data read from the PE/COFF image.
103 @retval EFI_SUCCESS The specified portion of the PE/COFF image was read and the size
107 DxeImageVerificationLibImageRead (
110 IN OUT UINTN
*ReadSize
,
116 if (FileHandle
== NULL
|| ReadSize
== NULL
|| Buffer
== NULL
) {
117 return EFI_INVALID_PARAMETER
;
120 if (MAX_ADDRESS
- FileOffset
< *ReadSize
) {
121 return EFI_INVALID_PARAMETER
;
124 EndPosition
= FileOffset
+ *ReadSize
;
125 if (EndPosition
> mImageSize
) {
126 *ReadSize
= (UINT32
)(mImageSize
- FileOffset
);
129 if (FileOffset
>= mImageSize
) {
133 CopyMem (Buffer
, (UINT8
*)((UINTN
) FileHandle
+ FileOffset
), *ReadSize
);
142 @param[in] File This is a pointer to the device path of the file that is
145 @return UINT32 Image Type
150 IN CONST EFI_DEVICE_PATH_PROTOCOL
*File
154 EFI_HANDLE DeviceHandle
;
155 EFI_DEVICE_PATH_PROTOCOL
*TempDevicePath
;
156 EFI_BLOCK_IO_PROTOCOL
*BlockIo
;
159 return IMAGE_UNKNOWN
;
163 // First check to see if File is from a Firmware Volume
166 TempDevicePath
= (EFI_DEVICE_PATH_PROTOCOL
*) File
;
167 Status
= gBS
->LocateDevicePath (
168 &gEfiFirmwareVolume2ProtocolGuid
,
172 if (!EFI_ERROR (Status
)) {
173 Status
= gBS
->OpenProtocol (
175 &gEfiFirmwareVolume2ProtocolGuid
,
179 EFI_OPEN_PROTOCOL_TEST_PROTOCOL
181 if (!EFI_ERROR (Status
)) {
182 return IMAGE_FROM_FV
;
187 // Next check to see if File is from a Block I/O device
190 TempDevicePath
= (EFI_DEVICE_PATH_PROTOCOL
*) File
;
191 Status
= gBS
->LocateDevicePath (
192 &gEfiBlockIoProtocolGuid
,
196 if (!EFI_ERROR (Status
)) {
198 Status
= gBS
->OpenProtocol (
200 &gEfiBlockIoProtocolGuid
,
204 EFI_OPEN_PROTOCOL_GET_PROTOCOL
206 if (!EFI_ERROR (Status
) && BlockIo
!= NULL
) {
207 if (BlockIo
->Media
!= NULL
) {
208 if (BlockIo
->Media
->RemovableMedia
) {
210 // Block I/O is present and specifies the media is removable
212 return IMAGE_FROM_REMOVABLE_MEDIA
;
215 // Block I/O is present and specifies the media is not removable
217 return IMAGE_FROM_FIXED_MEDIA
;
224 // File is not in a Firmware Volume or on a Block I/O device, so check to see if
225 // the device path supports the Simple File System Protocol.
228 TempDevicePath
= (EFI_DEVICE_PATH_PROTOCOL
*) File
;
229 Status
= gBS
->LocateDevicePath (
230 &gEfiSimpleFileSystemProtocolGuid
,
234 if (!EFI_ERROR (Status
)) {
236 // Simple File System is present without Block I/O, so assume media is fixed.
238 return IMAGE_FROM_FIXED_MEDIA
;
242 // File is not from an FV, Block I/O or Simple File System, so the only options
243 // left are a PCI Option ROM and a Load File Protocol such as a PXE Boot from a NIC.
245 TempDevicePath
= (EFI_DEVICE_PATH_PROTOCOL
*) File
;
246 while (!IsDevicePathEndType (TempDevicePath
)) {
247 switch (DevicePathType (TempDevicePath
)) {
249 case MEDIA_DEVICE_PATH
:
250 if (DevicePathSubType (TempDevicePath
) == MEDIA_RELATIVE_OFFSET_RANGE_DP
) {
251 return IMAGE_FROM_OPTION_ROM
;
255 case MESSAGING_DEVICE_PATH
:
256 if (DevicePathSubType(TempDevicePath
) == MSG_MAC_ADDR_DP
) {
257 return IMAGE_FROM_REMOVABLE_MEDIA
;
264 TempDevicePath
= NextDevicePathNode (TempDevicePath
);
266 return IMAGE_UNKNOWN
;
270 Calculate hash of Pe/Coff image based on the authenticode image hashing in
271 PE/COFF Specification 8.0 Appendix A
273 Caution: This function may receive untrusted input.
274 PE/COFF image is external input, so this function will validate its data structure
275 within this image buffer before use.
277 Notes: PE/COFF image has been checked by BasePeCoffLib PeCoffLoaderGetImageInfo() in
278 its caller function DxeImageVerificationHandler().
280 @param[in] HashAlg Hash algorithm type.
282 @retval TRUE Successfully hash image.
283 @retval FALSE Fail in hash image.
292 EFI_IMAGE_SECTION_HEADER
*Section
;
297 UINTN SumOfBytesHashed
;
298 EFI_IMAGE_SECTION_HEADER
*SectionHeader
;
302 UINT32 NumberOfRvaAndSizes
;
305 SectionHeader
= NULL
;
308 if ((HashAlg
>= HASHALG_MAX
)) {
313 // Initialize context of hash.
315 ZeroMem (mImageDigest
, MAX_DIGEST_SIZE
);
319 mImageDigestSize
= SHA1_DIGEST_SIZE
;
320 mCertType
= gEfiCertSha1Guid
;
324 mImageDigestSize
= SHA256_DIGEST_SIZE
;
325 mCertType
= gEfiCertSha256Guid
;
329 mImageDigestSize
= SHA384_DIGEST_SIZE
;
330 mCertType
= gEfiCertSha384Guid
;
334 mImageDigestSize
= SHA512_DIGEST_SIZE
;
335 mCertType
= gEfiCertSha512Guid
;
342 mHashTypeStr
= mHash
[HashAlg
].Name
;
343 CtxSize
= mHash
[HashAlg
].GetContextSize();
345 HashCtx
= AllocatePool (CtxSize
);
346 if (HashCtx
== NULL
) {
350 // 1. Load the image header into memory.
352 // 2. Initialize a SHA hash context.
353 Status
= mHash
[HashAlg
].HashInit(HashCtx
);
360 // Measuring PE/COFF Image Header;
361 // But CheckSum field and SECURITY data directory (certificate) are excluded
365 // 3. Calculate the distance from the base of the image header to the image checksum address.
366 // 4. Hash the image header from its base to beginning of the image checksum.
368 HashBase
= mImageBase
;
369 if (mNtHeader
.Pe32
->OptionalHeader
.Magic
== EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC
) {
373 HashSize
= (UINTN
) (&mNtHeader
.Pe32
->OptionalHeader
.CheckSum
) - (UINTN
) HashBase
;
374 NumberOfRvaAndSizes
= mNtHeader
.Pe32
->OptionalHeader
.NumberOfRvaAndSizes
;
375 } else if (mNtHeader
.Pe32
->OptionalHeader
.Magic
== EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC
) {
379 HashSize
= (UINTN
) (&mNtHeader
.Pe32Plus
->OptionalHeader
.CheckSum
) - (UINTN
) HashBase
;
380 NumberOfRvaAndSizes
= mNtHeader
.Pe32Plus
->OptionalHeader
.NumberOfRvaAndSizes
;
383 // Invalid header magic number.
389 Status
= mHash
[HashAlg
].HashUpdate(HashCtx
, HashBase
, HashSize
);
395 // 5. Skip over the image checksum (it occupies a single ULONG).
397 if (NumberOfRvaAndSizes
<= EFI_IMAGE_DIRECTORY_ENTRY_SECURITY
) {
399 // 6. Since there is no Cert Directory in optional header, hash everything
400 // from the end of the checksum to the end of image header.
402 if (mNtHeader
.Pe32
->OptionalHeader
.Magic
== EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC
) {
406 HashBase
= (UINT8
*) &mNtHeader
.Pe32
->OptionalHeader
.CheckSum
+ sizeof (UINT32
);
407 HashSize
= mNtHeader
.Pe32
->OptionalHeader
.SizeOfHeaders
- ((UINTN
) HashBase
- (UINTN
) mImageBase
);
412 HashBase
= (UINT8
*) &mNtHeader
.Pe32Plus
->OptionalHeader
.CheckSum
+ sizeof (UINT32
);
413 HashSize
= mNtHeader
.Pe32Plus
->OptionalHeader
.SizeOfHeaders
- ((UINTN
) HashBase
- (UINTN
) mImageBase
);
417 Status
= mHash
[HashAlg
].HashUpdate(HashCtx
, HashBase
, HashSize
);
424 // 7. Hash everything from the end of the checksum to the start of the Cert Directory.
426 if (mNtHeader
.Pe32
->OptionalHeader
.Magic
== EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC
) {
430 HashBase
= (UINT8
*) &mNtHeader
.Pe32
->OptionalHeader
.CheckSum
+ sizeof (UINT32
);
431 HashSize
= (UINTN
) (&mNtHeader
.Pe32
->OptionalHeader
.DataDirectory
[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY
]) - (UINTN
) HashBase
;
436 HashBase
= (UINT8
*) &mNtHeader
.Pe32Plus
->OptionalHeader
.CheckSum
+ sizeof (UINT32
);
437 HashSize
= (UINTN
) (&mNtHeader
.Pe32Plus
->OptionalHeader
.DataDirectory
[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY
]) - (UINTN
) HashBase
;
441 Status
= mHash
[HashAlg
].HashUpdate(HashCtx
, HashBase
, HashSize
);
448 // 8. Skip over the Cert Directory. (It is sizeof(IMAGE_DATA_DIRECTORY) bytes.)
449 // 9. Hash everything from the end of the Cert Directory to the end of image header.
451 if (mNtHeader
.Pe32
->OptionalHeader
.Magic
== EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC
) {
455 HashBase
= (UINT8
*) &mNtHeader
.Pe32
->OptionalHeader
.DataDirectory
[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY
+ 1];
456 HashSize
= mNtHeader
.Pe32
->OptionalHeader
.SizeOfHeaders
- ((UINTN
) HashBase
- (UINTN
) mImageBase
);
461 HashBase
= (UINT8
*) &mNtHeader
.Pe32Plus
->OptionalHeader
.DataDirectory
[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY
+ 1];
462 HashSize
= mNtHeader
.Pe32Plus
->OptionalHeader
.SizeOfHeaders
- ((UINTN
) HashBase
- (UINTN
) mImageBase
);
466 Status
= mHash
[HashAlg
].HashUpdate(HashCtx
, HashBase
, HashSize
);
474 // 10. Set the SUM_OF_BYTES_HASHED to the size of the header.
476 if (mNtHeader
.Pe32
->OptionalHeader
.Magic
== EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC
) {
480 SumOfBytesHashed
= mNtHeader
.Pe32
->OptionalHeader
.SizeOfHeaders
;
485 SumOfBytesHashed
= mNtHeader
.Pe32Plus
->OptionalHeader
.SizeOfHeaders
;
489 Section
= (EFI_IMAGE_SECTION_HEADER
*) (
491 mPeCoffHeaderOffset
+
493 sizeof (EFI_IMAGE_FILE_HEADER
) +
494 mNtHeader
.Pe32
->FileHeader
.SizeOfOptionalHeader
498 // 11. Build a temporary table of pointers to all the IMAGE_SECTION_HEADER
499 // structures in the image. The 'NumberOfSections' field of the image
500 // header indicates how big the table should be. Do not include any
501 // IMAGE_SECTION_HEADERs in the table whose 'SizeOfRawData' field is zero.
503 SectionHeader
= (EFI_IMAGE_SECTION_HEADER
*) AllocateZeroPool (sizeof (EFI_IMAGE_SECTION_HEADER
) * mNtHeader
.Pe32
->FileHeader
.NumberOfSections
);
504 if (SectionHeader
== NULL
) {
509 // 12. Using the 'PointerToRawData' in the referenced section headers as
510 // a key, arrange the elements in the table in ascending order. In other
511 // words, sort the section headers according to the disk-file offset of
514 for (Index
= 0; Index
< mNtHeader
.Pe32
->FileHeader
.NumberOfSections
; Index
++) {
516 while ((Pos
> 0) && (Section
->PointerToRawData
< SectionHeader
[Pos
- 1].PointerToRawData
)) {
517 CopyMem (&SectionHeader
[Pos
], &SectionHeader
[Pos
- 1], sizeof (EFI_IMAGE_SECTION_HEADER
));
520 CopyMem (&SectionHeader
[Pos
], Section
, sizeof (EFI_IMAGE_SECTION_HEADER
));
525 // 13. Walk through the sorted table, bring the corresponding section
526 // into memory, and hash the entire section (using the 'SizeOfRawData'
527 // field in the section header to determine the amount of data to hash).
528 // 14. Add the section's 'SizeOfRawData' to SUM_OF_BYTES_HASHED .
529 // 15. Repeat steps 13 and 14 for all the sections in the sorted table.
531 for (Index
= 0; Index
< mNtHeader
.Pe32
->FileHeader
.NumberOfSections
; Index
++) {
532 Section
= &SectionHeader
[Index
];
533 if (Section
->SizeOfRawData
== 0) {
536 HashBase
= mImageBase
+ Section
->PointerToRawData
;
537 HashSize
= (UINTN
) Section
->SizeOfRawData
;
539 Status
= mHash
[HashAlg
].HashUpdate(HashCtx
, HashBase
, HashSize
);
544 SumOfBytesHashed
+= HashSize
;
548 // 16. If the file size is greater than SUM_OF_BYTES_HASHED, there is extra
549 // data in the file that needs to be added to the hash. This data begins
550 // at file offset SUM_OF_BYTES_HASHED and its length is:
551 // FileSize - (CertDirectory->Size)
553 if (mImageSize
> SumOfBytesHashed
) {
554 HashBase
= mImageBase
+ SumOfBytesHashed
;
556 if (NumberOfRvaAndSizes
<= EFI_IMAGE_DIRECTORY_ENTRY_SECURITY
) {
559 if (mNtHeader
.Pe32
->OptionalHeader
.Magic
== EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC
) {
563 CertSize
= mNtHeader
.Pe32
->OptionalHeader
.DataDirectory
[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY
].Size
;
568 CertSize
= mNtHeader
.Pe32Plus
->OptionalHeader
.DataDirectory
[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY
].Size
;
572 if (mImageSize
> CertSize
+ SumOfBytesHashed
) {
573 HashSize
= (UINTN
) (mImageSize
- CertSize
- SumOfBytesHashed
);
575 Status
= mHash
[HashAlg
].HashUpdate(HashCtx
, HashBase
, HashSize
);
579 } else if (mImageSize
< CertSize
+ SumOfBytesHashed
) {
585 Status
= mHash
[HashAlg
].HashFinal(HashCtx
, mImageDigest
);
588 if (HashCtx
!= NULL
) {
591 if (SectionHeader
!= NULL
) {
592 FreePool (SectionHeader
);
598 Recognize the Hash algorithm in PE/COFF Authenticode and calculate hash of
599 Pe/Coff image based on the authenticode image hashing in PE/COFF Specification
602 Caution: This function may receive untrusted input.
603 PE/COFF image is external input, so this function will validate its data structure
604 within this image buffer before use.
606 @param[in] AuthData Pointer to the Authenticode Signature retrieved from signed image.
607 @param[in] AuthDataSize Size of the Authenticode Signature in bytes.
609 @retval EFI_UNSUPPORTED Hash algorithm is not supported.
610 @retval EFI_SUCCESS Hash successfully.
616 IN UINTN AuthDataSize
621 for (Index
= 0; Index
< HASHALG_MAX
; Index
++) {
623 // Check the Hash algorithm in PE/COFF Authenticode.
624 // According to PKCS#7 Definition:
625 // SignedData ::= SEQUENCE {
627 // digestAlgorithms DigestAlgorithmIdentifiers,
628 // contentInfo ContentInfo,
630 // The DigestAlgorithmIdentifiers can be used to determine the hash algorithm in PE/COFF hashing
631 // This field has the fixed offset (+32) in final Authenticode ASN.1 data.
632 // Fixed offset (+32) is calculated based on two bytes of length encoding.
634 if ((*(AuthData
+ 1) & TWO_BYTE_ENCODE
) != TWO_BYTE_ENCODE
) {
636 // Only support two bytes of Long Form of Length Encoding.
641 if (AuthDataSize
< 32 + mHash
[Index
].OidLength
) {
642 return EFI_UNSUPPORTED
;
645 if (CompareMem (AuthData
+ 32, mHash
[Index
].OidValue
, mHash
[Index
].OidLength
) == 0) {
650 if (Index
== HASHALG_MAX
) {
651 return EFI_UNSUPPORTED
;
655 // HASH PE Image based on Hash algorithm in PE/COFF Authenticode.
657 if (!HashPeImage(Index
)) {
658 return EFI_UNSUPPORTED
;
666 Returns the size of a given image execution info table in bytes.
668 This function returns the size, in bytes, of the image execution info table specified by
669 ImageExeInfoTable. If ImageExeInfoTable is NULL, then 0 is returned.
671 @param ImageExeInfoTable A pointer to a image execution info table structure.
673 @retval 0 If ImageExeInfoTable is NULL.
674 @retval Others The size of a image execution info table in bytes.
678 GetImageExeInfoTableSize (
679 EFI_IMAGE_EXECUTION_INFO_TABLE
*ImageExeInfoTable
683 EFI_IMAGE_EXECUTION_INFO
*ImageExeInfoItem
;
686 if (ImageExeInfoTable
== NULL
) {
690 ImageExeInfoItem
= (EFI_IMAGE_EXECUTION_INFO
*) ((UINT8
*) ImageExeInfoTable
+ sizeof (EFI_IMAGE_EXECUTION_INFO_TABLE
));
691 TotalSize
= sizeof (EFI_IMAGE_EXECUTION_INFO_TABLE
);
692 for (Index
= 0; Index
< ImageExeInfoTable
->NumberOfImages
; Index
++) {
693 TotalSize
+= ReadUnaligned32 ((UINT32
*) &ImageExeInfoItem
->InfoSize
);
694 ImageExeInfoItem
= (EFI_IMAGE_EXECUTION_INFO
*) ((UINT8
*) ImageExeInfoItem
+ ReadUnaligned32 ((UINT32
*) &ImageExeInfoItem
->InfoSize
));
701 Create an Image Execution Information Table entry and add it to system configuration table.
703 @param[in] Action Describes the action taken by the firmware regarding this image.
704 @param[in] Name Input a null-terminated, user-friendly name.
705 @param[in] DevicePath Input device path pointer.
706 @param[in] Signature Input signature info in EFI_SIGNATURE_LIST data structure.
707 @param[in] SignatureSize Size of signature. Must be zero if Signature is NULL.
712 IN EFI_IMAGE_EXECUTION_ACTION Action
,
713 IN CHAR16
*Name OPTIONAL
,
714 IN CONST EFI_DEVICE_PATH_PROTOCOL
*DevicePath
,
715 IN EFI_SIGNATURE_LIST
*Signature OPTIONAL
,
716 IN UINTN SignatureSize
719 EFI_IMAGE_EXECUTION_INFO_TABLE
*ImageExeInfoTable
;
720 EFI_IMAGE_EXECUTION_INFO_TABLE
*NewImageExeInfoTable
;
721 EFI_IMAGE_EXECUTION_INFO
*ImageExeInfoEntry
;
722 UINTN ImageExeInfoTableSize
;
723 UINTN NewImageExeInfoEntrySize
;
725 UINTN DevicePathSize
;
728 ImageExeInfoTable
= NULL
;
729 NewImageExeInfoTable
= NULL
;
730 ImageExeInfoEntry
= NULL
;
734 if (DevicePath
== NULL
) {
739 NameStringLen
= StrSize (Name
);
741 NameStringLen
= sizeof (CHAR16
);
744 EfiGetSystemConfigurationTable (&gEfiImageSecurityDatabaseGuid
, (VOID
**) &ImageExeInfoTable
);
745 if (ImageExeInfoTable
!= NULL
) {
747 // The table has been found!
748 // We must enlarge the table to accommodate the new exe info entry.
750 ImageExeInfoTableSize
= GetImageExeInfoTableSize (ImageExeInfoTable
);
754 // We should create a new table to append to the configuration table.
756 ImageExeInfoTableSize
= sizeof (EFI_IMAGE_EXECUTION_INFO_TABLE
);
759 DevicePathSize
= GetDevicePathSize (DevicePath
);
762 // Signature size can be odd. Pad after signature to ensure next EXECUTION_INFO entry align
764 ASSERT (Signature
!= NULL
|| SignatureSize
== 0);
765 NewImageExeInfoEntrySize
= sizeof (EFI_IMAGE_EXECUTION_INFO
) + NameStringLen
+ DevicePathSize
+ SignatureSize
;
767 NewImageExeInfoTable
= (EFI_IMAGE_EXECUTION_INFO_TABLE
*) AllocateRuntimePool (ImageExeInfoTableSize
+ NewImageExeInfoEntrySize
);
768 if (NewImageExeInfoTable
== NULL
) {
772 if (ImageExeInfoTable
!= NULL
) {
773 CopyMem (NewImageExeInfoTable
, ImageExeInfoTable
, ImageExeInfoTableSize
);
775 NewImageExeInfoTable
->NumberOfImages
= 0;
777 NewImageExeInfoTable
->NumberOfImages
++;
778 ImageExeInfoEntry
= (EFI_IMAGE_EXECUTION_INFO
*) ((UINT8
*) NewImageExeInfoTable
+ ImageExeInfoTableSize
);
780 // Update new item's information.
782 WriteUnaligned32 ((UINT32
*) ImageExeInfoEntry
, Action
);
783 WriteUnaligned32 ((UINT32
*) ((UINT8
*) ImageExeInfoEntry
+ sizeof (EFI_IMAGE_EXECUTION_ACTION
)), (UINT32
) NewImageExeInfoEntrySize
);
785 NameStr
= (CHAR16
*)(ImageExeInfoEntry
+ 1);
787 CopyMem ((UINT8
*) NameStr
, Name
, NameStringLen
);
789 ZeroMem ((UINT8
*) NameStr
, sizeof (CHAR16
));
793 (UINT8
*) NameStr
+ NameStringLen
,
797 if (Signature
!= NULL
) {
799 (UINT8
*) NameStr
+ NameStringLen
+ DevicePathSize
,
805 // Update/replace the image execution table.
807 gBS
->InstallConfigurationTable (&gEfiImageSecurityDatabaseGuid
, (VOID
*) NewImageExeInfoTable
);
810 // Free Old table data!
812 if (ImageExeInfoTable
!= NULL
) {
813 FreePool (ImageExeInfoTable
);
818 Check whether the hash of an given X.509 certificate is in forbidden database (DBX).
820 @param[in] Certificate Pointer to X.509 Certificate that is searched for.
821 @param[in] CertSize Size of X.509 Certificate.
822 @param[in] SignatureList Pointer to the Signature List in forbidden database.
823 @param[in] SignatureListSize Size of Signature List.
824 @param[out] RevocationTime Return the time that the certificate was revoked.
825 @param[out] IsFound Search result. Only valid if EFI_SUCCESS returned.
827 @retval EFI_SUCCESS Finished the search without any error.
828 @retval Others Error occurred in the search of database.
832 IsCertHashFoundInDbx (
833 IN UINT8
*Certificate
,
835 IN EFI_SIGNATURE_LIST
*SignatureList
,
836 IN UINTN SignatureListSize
,
837 OUT EFI_TIME
*RevocationTime
,
842 EFI_SIGNATURE_LIST
*DbxList
;
844 EFI_SIGNATURE_DATA
*CertHash
;
849 UINT8 CertDigest
[MAX_DIGEST_SIZE
];
851 UINTN SiglistHeaderSize
;
855 Status
= EFI_ABORTED
;
857 DbxList
= SignatureList
;
858 DbxSize
= SignatureListSize
;
860 HashAlg
= HASHALG_MAX
;
862 if ((RevocationTime
== NULL
) || (DbxList
== NULL
)) {
863 return EFI_INVALID_PARAMETER
;
867 // Retrieve the TBSCertificate from the X.509 Certificate.
869 if (!X509GetTBSCert (Certificate
, CertSize
, &TBSCert
, &TBSCertSize
)) {
873 while ((DbxSize
> 0) && (SignatureListSize
>= DbxList
->SignatureListSize
)) {
875 // Determine Hash Algorithm of Certificate in the forbidden database.
877 if (CompareGuid (&DbxList
->SignatureType
, &gEfiCertX509Sha256Guid
)) {
878 HashAlg
= HASHALG_SHA256
;
879 } else if (CompareGuid (&DbxList
->SignatureType
, &gEfiCertX509Sha384Guid
)) {
880 HashAlg
= HASHALG_SHA384
;
881 } else if (CompareGuid (&DbxList
->SignatureType
, &gEfiCertX509Sha512Guid
)) {
882 HashAlg
= HASHALG_SHA512
;
884 DbxSize
-= DbxList
->SignatureListSize
;
885 DbxList
= (EFI_SIGNATURE_LIST
*) ((UINT8
*) DbxList
+ DbxList
->SignatureListSize
);
890 // Calculate the hash value of current TBSCertificate for comparision.
892 if (mHash
[HashAlg
].GetContextSize
== NULL
) {
895 ZeroMem (CertDigest
, MAX_DIGEST_SIZE
);
896 HashCtx
= AllocatePool (mHash
[HashAlg
].GetContextSize ());
897 if (HashCtx
== NULL
) {
900 if (!mHash
[HashAlg
].HashInit (HashCtx
)) {
903 if (!mHash
[HashAlg
].HashUpdate (HashCtx
, TBSCert
, TBSCertSize
)) {
906 if (!mHash
[HashAlg
].HashFinal (HashCtx
, CertDigest
)) {
913 SiglistHeaderSize
= sizeof (EFI_SIGNATURE_LIST
) + DbxList
->SignatureHeaderSize
;
914 CertHash
= (EFI_SIGNATURE_DATA
*) ((UINT8
*) DbxList
+ SiglistHeaderSize
);
915 CertHashCount
= (DbxList
->SignatureListSize
- SiglistHeaderSize
) / DbxList
->SignatureSize
;
916 for (Index
= 0; Index
< CertHashCount
; Index
++) {
918 // Iterate each Signature Data Node within this CertList for verify.
920 DbxCertHash
= CertHash
->SignatureData
;
921 if (CompareMem (DbxCertHash
, CertDigest
, mHash
[HashAlg
].DigestLength
) == 0) {
923 // Hash of Certificate is found in forbidden database.
925 Status
= EFI_SUCCESS
;
929 // Return the revocation time.
931 CopyMem (RevocationTime
, (EFI_TIME
*)(DbxCertHash
+ mHash
[HashAlg
].DigestLength
), sizeof (EFI_TIME
));
934 CertHash
= (EFI_SIGNATURE_DATA
*) ((UINT8
*) CertHash
+ DbxList
->SignatureSize
);
937 DbxSize
-= DbxList
->SignatureListSize
;
938 DbxList
= (EFI_SIGNATURE_LIST
*) ((UINT8
*) DbxList
+ DbxList
->SignatureListSize
);
941 Status
= EFI_SUCCESS
;
944 if (HashCtx
!= NULL
) {
952 Check whether signature is in specified database.
954 @param[in] VariableName Name of database variable that is searched in.
955 @param[in] Signature Pointer to signature that is searched for.
956 @param[in] CertType Pointer to hash algorithm.
957 @param[in] SignatureSize Size of Signature.
958 @param[out] IsFound Search result. Only valid if EFI_SUCCESS returned
960 @retval EFI_SUCCESS Finished the search without any error.
961 @retval Others Error occurred in the search of database.
965 IsSignatureFoundInDatabase (
966 IN CHAR16
*VariableName
,
968 IN EFI_GUID
*CertType
,
969 IN UINTN SignatureSize
,
974 EFI_SIGNATURE_LIST
*CertList
;
975 EFI_SIGNATURE_DATA
*Cert
;
982 // Read signature database variable.
987 Status
= gRT
->GetVariable (VariableName
, &gEfiImageSecurityDatabaseGuid
, NULL
, &DataSize
, NULL
);
988 if (Status
!= EFI_BUFFER_TOO_SMALL
) {
989 if (Status
== EFI_NOT_FOUND
) {
991 // No database, no need to search.
993 Status
= EFI_SUCCESS
;
999 Data
= (UINT8
*) AllocateZeroPool (DataSize
);
1001 return EFI_OUT_OF_RESOURCES
;
1004 Status
= gRT
->GetVariable (VariableName
, &gEfiImageSecurityDatabaseGuid
, NULL
, &DataSize
, Data
);
1005 if (EFI_ERROR (Status
)) {
1009 // Enumerate all signature data in SigDB to check if signature exists for executable.
1011 CertList
= (EFI_SIGNATURE_LIST
*) Data
;
1012 while ((DataSize
> 0) && (DataSize
>= CertList
->SignatureListSize
)) {
1013 CertCount
= (CertList
->SignatureListSize
- sizeof (EFI_SIGNATURE_LIST
) - CertList
->SignatureHeaderSize
) / CertList
->SignatureSize
;
1014 Cert
= (EFI_SIGNATURE_DATA
*) ((UINT8
*) CertList
+ sizeof (EFI_SIGNATURE_LIST
) + CertList
->SignatureHeaderSize
);
1015 if ((CertList
->SignatureSize
== sizeof(EFI_SIGNATURE_DATA
) - 1 + SignatureSize
) && (CompareGuid(&CertList
->SignatureType
, CertType
))) {
1016 for (Index
= 0; Index
< CertCount
; Index
++) {
1017 if (CompareMem (Cert
->SignatureData
, Signature
, SignatureSize
) == 0) {
1019 // Find the signature in database.
1023 // Entries in UEFI_IMAGE_SECURITY_DATABASE that are used to validate image should be measured
1025 if (StrCmp(VariableName
, EFI_IMAGE_SECURITY_DATABASE
) == 0) {
1026 SecureBootHook (VariableName
, &gEfiImageSecurityDatabaseGuid
, CertList
->SignatureSize
, Cert
);
1031 Cert
= (EFI_SIGNATURE_DATA
*) ((UINT8
*) Cert
+ CertList
->SignatureSize
);
1039 DataSize
-= CertList
->SignatureListSize
;
1040 CertList
= (EFI_SIGNATURE_LIST
*) ((UINT8
*) CertList
+ CertList
->SignatureListSize
);
1052 Check whether the timestamp is valid by comparing the signing time and the revocation time.
1054 @param SigningTime A pointer to the signing time.
1055 @param RevocationTime A pointer to the revocation time.
1057 @retval TRUE The SigningTime is not later than the RevocationTime.
1058 @retval FALSE The SigningTime is later than the RevocationTime.
1062 IsValidSignatureByTimestamp (
1063 IN EFI_TIME
*SigningTime
,
1064 IN EFI_TIME
*RevocationTime
1067 if (SigningTime
->Year
!= RevocationTime
->Year
) {
1068 return (BOOLEAN
) (SigningTime
->Year
< RevocationTime
->Year
);
1069 } else if (SigningTime
->Month
!= RevocationTime
->Month
) {
1070 return (BOOLEAN
) (SigningTime
->Month
< RevocationTime
->Month
);
1071 } else if (SigningTime
->Day
!= RevocationTime
->Day
) {
1072 return (BOOLEAN
) (SigningTime
->Day
< RevocationTime
->Day
);
1073 } else if (SigningTime
->Hour
!= RevocationTime
->Hour
) {
1074 return (BOOLEAN
) (SigningTime
->Hour
< RevocationTime
->Hour
);
1075 } else if (SigningTime
->Minute
!= RevocationTime
->Minute
) {
1076 return (BOOLEAN
) (SigningTime
->Minute
< RevocationTime
->Minute
);
1079 return (BOOLEAN
) (SigningTime
->Second
<= RevocationTime
->Second
);
1083 Check if the given time value is zero.
1085 @param[in] Time Pointer of a time value.
1087 @retval TRUE The Time is Zero.
1088 @retval FALSE The Time is not Zero.
1096 if ((Time
->Year
== 0) && (Time
->Month
== 0) && (Time
->Day
== 0) &&
1097 (Time
->Hour
== 0) && (Time
->Minute
== 0) && (Time
->Second
== 0)) {
1105 Check whether the timestamp signature is valid and the signing time is also earlier than
1106 the revocation time.
1108 @param[in] AuthData Pointer to the Authenticode signature retrieved from signed image.
1109 @param[in] AuthDataSize Size of the Authenticode signature in bytes.
1110 @param[in] RevocationTime The time that the certificate was revoked.
1112 @retval TRUE Timestamp signature is valid and signing time is no later than the
1114 @retval FALSE Timestamp signature is not valid or the signing time is later than the
1119 PassTimestampCheck (
1121 IN UINTN AuthDataSize
,
1122 IN EFI_TIME
*RevocationTime
1126 BOOLEAN VerifyStatus
;
1127 EFI_SIGNATURE_LIST
*CertList
;
1128 EFI_SIGNATURE_DATA
*Cert
;
1135 EFI_TIME SigningTime
;
1138 // Variable Initialization
1140 VerifyStatus
= FALSE
;
1148 // If RevocationTime is zero, the certificate shall be considered to always be revoked.
1150 if (IsTimeZero (RevocationTime
)) {
1155 // RevocationTime is non-zero, the certificate should be considered to be revoked from that time and onwards.
1156 // Using the dbt to get the trusted TSA certificates.
1159 Status
= gRT
->GetVariable (EFI_IMAGE_SECURITY_DATABASE2
, &gEfiImageSecurityDatabaseGuid
, NULL
, &DbtDataSize
, NULL
);
1160 if (Status
!= EFI_BUFFER_TOO_SMALL
) {
1163 DbtData
= (UINT8
*) AllocateZeroPool (DbtDataSize
);
1164 if (DbtData
== NULL
) {
1167 Status
= gRT
->GetVariable (EFI_IMAGE_SECURITY_DATABASE2
, &gEfiImageSecurityDatabaseGuid
, NULL
, &DbtDataSize
, (VOID
*) DbtData
);
1168 if (EFI_ERROR (Status
)) {
1172 CertList
= (EFI_SIGNATURE_LIST
*) DbtData
;
1173 while ((DbtDataSize
> 0) && (DbtDataSize
>= CertList
->SignatureListSize
)) {
1174 if (CompareGuid (&CertList
->SignatureType
, &gEfiCertX509Guid
)) {
1175 Cert
= (EFI_SIGNATURE_DATA
*) ((UINT8
*) CertList
+ sizeof (EFI_SIGNATURE_LIST
) + CertList
->SignatureHeaderSize
);
1176 CertCount
= (CertList
->SignatureListSize
- sizeof (EFI_SIGNATURE_LIST
) - CertList
->SignatureHeaderSize
) / CertList
->SignatureSize
;
1177 for (Index
= 0; Index
< CertCount
; Index
++) {
1179 // Iterate each Signature Data Node within this CertList for verify.
1181 RootCert
= Cert
->SignatureData
;
1182 RootCertSize
= CertList
->SignatureSize
- sizeof (EFI_GUID
);
1184 // Get the signing time if the timestamp signature is valid.
1186 if (ImageTimestampVerify (AuthData
, AuthDataSize
, RootCert
, RootCertSize
, &SigningTime
)) {
1188 // The signer signature is valid only when the signing time is earlier than revocation time.
1190 if (IsValidSignatureByTimestamp (&SigningTime
, RevocationTime
)) {
1191 VerifyStatus
= TRUE
;
1195 Cert
= (EFI_SIGNATURE_DATA
*) ((UINT8
*) Cert
+ CertList
->SignatureSize
);
1198 DbtDataSize
-= CertList
->SignatureListSize
;
1199 CertList
= (EFI_SIGNATURE_LIST
*) ((UINT8
*) CertList
+ CertList
->SignatureListSize
);
1203 if (DbtData
!= NULL
) {
1207 return VerifyStatus
;
1211 Check whether the image signature is forbidden by the forbidden database (dbx).
1212 The image is forbidden to load if any certificates for signing are revoked before signing time.
1214 @param[in] AuthData Pointer to the Authenticode signature retrieved from the signed image.
1215 @param[in] AuthDataSize Size of the Authenticode signature in bytes.
1217 @retval TRUE Image is forbidden by dbx.
1218 @retval FALSE Image is not forbidden by dbx.
1224 IN UINTN AuthDataSize
1228 BOOLEAN IsForbidden
;
1232 EFI_SIGNATURE_LIST
*CertList
;
1234 EFI_SIGNATURE_DATA
*CertData
;
1242 UINTN TrustedCertLength
;
1247 EFI_TIME RevocationTime
;
1249 // Variable Initialization
1261 TrustedCertLength
= 0;
1264 // The image will not be forbidden if dbx can't be got.
1267 Status
= gRT
->GetVariable (EFI_IMAGE_SECURITY_DATABASE1
, &gEfiImageSecurityDatabaseGuid
, NULL
, &DataSize
, NULL
);
1268 ASSERT (EFI_ERROR (Status
));
1269 if (Status
!= EFI_BUFFER_TOO_SMALL
) {
1270 if (Status
== EFI_NOT_FOUND
) {
1272 // Evidently not in dbx if the database doesn't exist.
1274 IsForbidden
= FALSE
;
1278 Data
= (UINT8
*) AllocateZeroPool (DataSize
);
1283 Status
= gRT
->GetVariable (EFI_IMAGE_SECURITY_DATABASE1
, &gEfiImageSecurityDatabaseGuid
, NULL
, &DataSize
, (VOID
*) Data
);
1284 if (EFI_ERROR (Status
)) {
1289 // Verify image signature with RAW X509 certificates in DBX database.
1290 // If passed, the image will be forbidden.
1292 CertList
= (EFI_SIGNATURE_LIST
*) Data
;
1293 CertListSize
= DataSize
;
1294 while ((CertListSize
> 0) && (CertListSize
>= CertList
->SignatureListSize
)) {
1295 if (CompareGuid (&CertList
->SignatureType
, &gEfiCertX509Guid
)) {
1296 CertData
= (EFI_SIGNATURE_DATA
*) ((UINT8
*) CertList
+ sizeof (EFI_SIGNATURE_LIST
) + CertList
->SignatureHeaderSize
);
1297 CertCount
= (CertList
->SignatureListSize
- sizeof (EFI_SIGNATURE_LIST
) - CertList
->SignatureHeaderSize
) / CertList
->SignatureSize
;
1299 for (Index
= 0; Index
< CertCount
; Index
++) {
1301 // Iterate each Signature Data Node within this CertList for verify.
1303 RootCert
= CertData
->SignatureData
;
1304 RootCertSize
= CertList
->SignatureSize
- sizeof (EFI_GUID
);
1307 // Call AuthenticodeVerify library to Verify Authenticode struct.
1309 IsForbidden
= AuthenticodeVerify (
1318 DEBUG ((DEBUG_INFO
, "DxeImageVerificationLib: Image is signed but signature is forbidden by DBX.\n"));
1322 CertData
= (EFI_SIGNATURE_DATA
*) ((UINT8
*) CertData
+ CertList
->SignatureSize
);
1326 CertListSize
-= CertList
->SignatureListSize
;
1327 CertList
= (EFI_SIGNATURE_LIST
*) ((UINT8
*) CertList
+ CertList
->SignatureListSize
);
1331 // Check X.509 Certificate Hash & Possible Timestamp.
1335 // Retrieve the certificate stack from AuthData
1336 // The output CertStack format will be:
1337 // UINT8 CertNumber;
1338 // UINT32 Cert1Length;
1340 // UINT32 Cert2Length;
1343 // UINT32 CertnLength;
1346 Pkcs7GetSigners (AuthData
, AuthDataSize
, &CertBuffer
, &BufferLength
, &TrustedCert
, &TrustedCertLength
);
1347 if ((BufferLength
== 0) || (CertBuffer
== NULL
) || (*CertBuffer
) == 0) {
1353 // Check if any hash of certificates embedded in AuthData is in the forbidden database.
1355 CertNumber
= (UINT8
) (*CertBuffer
);
1356 CertPtr
= CertBuffer
+ 1;
1357 for (Index
= 0; Index
< CertNumber
; Index
++) {
1358 CertSize
= (UINTN
) ReadUnaligned32 ((UINT32
*)CertPtr
);
1359 Cert
= (UINT8
*)CertPtr
+ sizeof (UINT32
);
1361 // Advance CertPtr to the next cert in image signer's cert list
1363 CertPtr
= CertPtr
+ sizeof (UINT32
) + CertSize
;
1365 Status
= IsCertHashFoundInDbx (Cert
, CertSize
, (EFI_SIGNATURE_LIST
*)Data
, DataSize
, &RevocationTime
, &IsFound
);
1366 if (EFI_ERROR (Status
)) {
1368 // Error in searching dbx. Consider it as 'found'. RevocationTime might
1369 // not be valid in such situation.
1372 } else if (IsFound
) {
1374 // Found Cert in dbx successfully. Check the timestamp signature and
1375 // signing time to determine if the image can be trusted.
1377 if (PassTimestampCheck (AuthData
, AuthDataSize
, &RevocationTime
)) {
1378 IsForbidden
= FALSE
;
1380 // Pass DBT check. Continue to check other certs in image signer's cert list against DBX, DBT
1385 DEBUG ((DEBUG_INFO
, "DxeImageVerificationLib: Image is signed but signature failed the timestamp check.\n"));
1392 IsForbidden
= FALSE
;
1399 Pkcs7FreeSigners (CertBuffer
);
1400 Pkcs7FreeSigners (TrustedCert
);
1407 Check whether the image signature can be verified by the trusted certificates in DB database.
1409 @param[in] AuthData Pointer to the Authenticode signature retrieved from signed image.
1410 @param[in] AuthDataSize Size of the Authenticode signature in bytes.
1412 @retval TRUE Image passed verification using certificate in db.
1413 @retval FALSE Image didn't pass verification using certificate in db.
1419 IN UINTN AuthDataSize
1423 BOOLEAN VerifyStatus
;
1425 EFI_SIGNATURE_LIST
*CertList
;
1426 EFI_SIGNATURE_DATA
*CertData
;
1435 EFI_TIME RevocationTime
;
1443 VerifyStatus
= FALSE
;
1446 // Fetch 'db' content. If 'db' doesn't exist or encounters problem to get the
1447 // data, return not-allowed-by-db (FALSE).
1450 Status
= gRT
->GetVariable (EFI_IMAGE_SECURITY_DATABASE
, &gEfiImageSecurityDatabaseGuid
, NULL
, &DataSize
, NULL
);
1451 ASSERT (EFI_ERROR (Status
));
1452 if (Status
!= EFI_BUFFER_TOO_SMALL
) {
1453 return VerifyStatus
;
1456 Data
= (UINT8
*) AllocateZeroPool (DataSize
);
1458 return VerifyStatus
;
1461 Status
= gRT
->GetVariable (EFI_IMAGE_SECURITY_DATABASE
, &gEfiImageSecurityDatabaseGuid
, NULL
, &DataSize
, (VOID
*) Data
);
1462 if (EFI_ERROR (Status
)) {
1467 // Fetch 'dbx' content. If 'dbx' doesn't exist, continue to check 'db'.
1468 // If any other errors occured, no need to check 'db' but just return
1469 // not-allowed-by-db (FALSE) to avoid bypass.
1472 Status
= gRT
->GetVariable (EFI_IMAGE_SECURITY_DATABASE1
, &gEfiImageSecurityDatabaseGuid
, NULL
, &DbxDataSize
, NULL
);
1473 ASSERT (EFI_ERROR (Status
));
1474 if (Status
!= EFI_BUFFER_TOO_SMALL
) {
1475 if (Status
!= EFI_NOT_FOUND
) {
1479 // 'dbx' does not exist. Continue to check 'db'.
1483 // 'dbx' exists. Get its content.
1485 DbxData
= (UINT8
*) AllocateZeroPool (DbxDataSize
);
1486 if (DbxData
== NULL
) {
1490 Status
= gRT
->GetVariable (EFI_IMAGE_SECURITY_DATABASE1
, &gEfiImageSecurityDatabaseGuid
, NULL
, &DbxDataSize
, (VOID
*) DbxData
);
1491 if (EFI_ERROR (Status
)) {
1497 // Find X509 certificate in Signature List to verify the signature in pkcs7 signed data.
1499 CertList
= (EFI_SIGNATURE_LIST
*) Data
;
1500 while ((DataSize
> 0) && (DataSize
>= CertList
->SignatureListSize
)) {
1501 if (CompareGuid (&CertList
->SignatureType
, &gEfiCertX509Guid
)) {
1502 CertData
= (EFI_SIGNATURE_DATA
*) ((UINT8
*) CertList
+ sizeof (EFI_SIGNATURE_LIST
) + CertList
->SignatureHeaderSize
);
1503 CertCount
= (CertList
->SignatureListSize
- sizeof (EFI_SIGNATURE_LIST
) - CertList
->SignatureHeaderSize
) / CertList
->SignatureSize
;
1505 for (Index
= 0; Index
< CertCount
; Index
++) {
1507 // Iterate each Signature Data Node within this CertList for verify.
1509 RootCert
= CertData
->SignatureData
;
1510 RootCertSize
= CertList
->SignatureSize
- sizeof (EFI_GUID
);
1513 // Call AuthenticodeVerify library to Verify Authenticode struct.
1515 VerifyStatus
= AuthenticodeVerify (
1525 // The image is signed and its signature is found in 'db'.
1527 if (DbxData
!= NULL
) {
1529 // Here We still need to check if this RootCert's Hash is revoked
1531 Status
= IsCertHashFoundInDbx (RootCert
, RootCertSize
, (EFI_SIGNATURE_LIST
*)DbxData
, DbxDataSize
, &RevocationTime
, &IsFound
);
1532 if (EFI_ERROR (Status
)) {
1534 // Error in searching dbx. Consider it as 'found'. RevocationTime might
1535 // not be valid in such situation.
1537 VerifyStatus
= FALSE
;
1538 } else if (IsFound
) {
1540 // Check the timestamp signature and signing time to determine if the RootCert can be trusted.
1542 VerifyStatus
= PassTimestampCheck (AuthData
, AuthDataSize
, &RevocationTime
);
1543 if (!VerifyStatus
) {
1544 DEBUG ((DEBUG_INFO
, "DxeImageVerificationLib: Image is signed and signature is accepted by DB, but its root cert failed the timestamp check.\n"));
1550 // There's no 'dbx' to check revocation time against (must-be pass),
1551 // or, there's revocation time found in 'dbx' and checked againt 'dbt'
1552 // (maybe pass or fail, depending on timestamp compare result). Either
1553 // way the verification job has been completed at this point.
1558 CertData
= (EFI_SIGNATURE_DATA
*) ((UINT8
*) CertData
+ CertList
->SignatureSize
);
1562 DataSize
-= CertList
->SignatureListSize
;
1563 CertList
= (EFI_SIGNATURE_LIST
*) ((UINT8
*) CertList
+ CertList
->SignatureListSize
);
1569 SecureBootHook (EFI_IMAGE_SECURITY_DATABASE
, &gEfiImageSecurityDatabaseGuid
, CertList
->SignatureSize
, CertData
);
1575 if (DbxData
!= NULL
) {
1579 return VerifyStatus
;
1583 Provide verification service for signed images, which include both signature validation
1584 and platform policy control. For signature types, both UEFI WIN_CERTIFICATE_UEFI_GUID and
1585 MSFT Authenticode type signatures are supported.
1587 In this implementation, only verify external executables when in USER MODE.
1588 Executables from FV is bypass, so pass in AuthenticationStatus is ignored.
1590 The image verification policy is:
1591 If the image is signed,
1592 At least one valid signature or at least one hash value of the image must match a record
1593 in the security database "db", and no valid signature nor any hash value of the image may
1594 be reflected in the security database "dbx".
1595 Otherwise, the image is not signed,
1596 The SHA256 hash value of the image must match a record in the security database "db", and
1597 not be reflected in the security data base "dbx".
1599 Caution: This function may receive untrusted input.
1600 PE/COFF image is external input, so this function will validate its data structure
1601 within this image buffer before use.
1603 @param[in] AuthenticationStatus
1604 This is the authentication status returned from the security
1605 measurement services for the input file.
1606 @param[in] File This is a pointer to the device path of the file that is
1607 being dispatched. This will optionally be used for logging.
1608 @param[in] FileBuffer File buffer matches the input file device path.
1609 @param[in] FileSize Size of File buffer matches the input file device path.
1610 @param[in] BootPolicy A boot policy that was used to call LoadImage() UEFI service.
1612 @retval EFI_SUCCESS The file specified by DevicePath and non-NULL
1613 FileBuffer did authenticate, and the platform policy dictates
1614 that the DXE Foundation may use the file.
1615 @retval EFI_SUCCESS The device path specified by NULL device path DevicePath
1616 and non-NULL FileBuffer did authenticate, and the platform
1617 policy dictates that the DXE Foundation may execute the image in
1619 @retval EFI_SECURITY_VIOLATION The file specified by File did not authenticate, and
1620 the platform policy dictates that File should be placed
1621 in the untrusted state. The image has been added to the file
1623 @retval EFI_ACCESS_DENIED The file specified by File and FileBuffer did not
1624 authenticate, and the platform policy dictates that the DXE
1625 Foundation may not use File. The image has
1626 been added to the file execution table.
1631 DxeImageVerificationHandler (
1632 IN UINT32 AuthenticationStatus
,
1633 IN CONST EFI_DEVICE_PATH_PROTOCOL
*File
, OPTIONAL
1634 IN VOID
*FileBuffer
,
1636 IN BOOLEAN BootPolicy
1639 EFI_IMAGE_DOS_HEADER
*DosHdr
;
1641 EFI_SIGNATURE_LIST
*SignatureList
;
1642 UINTN SignatureListSize
;
1643 EFI_SIGNATURE_DATA
*Signature
;
1644 EFI_IMAGE_EXECUTION_ACTION Action
;
1645 WIN_CERTIFICATE
*WinCertificate
;
1648 PE_COFF_LOADER_IMAGE_CONTEXT ImageContext
;
1649 UINT32 NumberOfRvaAndSizes
;
1650 WIN_CERTIFICATE_EFI_PKCS
*PkcsCertData
;
1651 WIN_CERTIFICATE_UEFI_GUID
*WinCertUefiGuid
;
1654 EFI_IMAGE_DATA_DIRECTORY
*SecDataDir
;
1657 RETURN_STATUS PeCoffStatus
;
1658 EFI_STATUS HashStatus
;
1659 EFI_STATUS DbStatus
;
1662 SignatureList
= NULL
;
1663 SignatureListSize
= 0;
1664 WinCertificate
= NULL
;
1666 PkcsCertData
= NULL
;
1667 Action
= EFI_IMAGE_EXECUTION_AUTH_UNTESTED
;
1672 // Check the image type and get policy setting.
1674 switch (GetImageType (File
)) {
1677 Policy
= ALWAYS_EXECUTE
;
1680 case IMAGE_FROM_OPTION_ROM
:
1681 Policy
= PcdGet32 (PcdOptionRomImageVerificationPolicy
);
1684 case IMAGE_FROM_REMOVABLE_MEDIA
:
1685 Policy
= PcdGet32 (PcdRemovableMediaImageVerificationPolicy
);
1688 case IMAGE_FROM_FIXED_MEDIA
:
1689 Policy
= PcdGet32 (PcdFixedMediaImageVerificationPolicy
);
1693 Policy
= DENY_EXECUTE_ON_SECURITY_VIOLATION
;
1697 // If policy is always/never execute, return directly.
1699 if (Policy
== ALWAYS_EXECUTE
) {
1702 if (Policy
== NEVER_EXECUTE
) {
1703 return EFI_ACCESS_DENIED
;
1707 // The policy QUERY_USER_ON_SECURITY_VIOLATION and ALLOW_EXECUTE_ON_SECURITY_VIOLATION
1708 // violates the UEFI spec and has been removed.
1710 ASSERT (Policy
!= QUERY_USER_ON_SECURITY_VIOLATION
&& Policy
!= ALLOW_EXECUTE_ON_SECURITY_VIOLATION
);
1711 if (Policy
== QUERY_USER_ON_SECURITY_VIOLATION
|| Policy
== ALLOW_EXECUTE_ON_SECURITY_VIOLATION
) {
1715 GetEfiGlobalVariable2 (EFI_SECURE_BOOT_MODE_NAME
, (VOID
**)&SecureBoot
, NULL
);
1717 // Skip verification if SecureBoot variable doesn't exist.
1719 if (SecureBoot
== NULL
) {
1724 // Skip verification if SecureBoot is disabled but not AuditMode
1726 if (*SecureBoot
== SECURE_BOOT_MODE_DISABLE
) {
1727 FreePool (SecureBoot
);
1730 FreePool (SecureBoot
);
1733 // Read the Dos header.
1735 if (FileBuffer
== NULL
) {
1736 return EFI_ACCESS_DENIED
;
1739 mImageBase
= (UINT8
*) FileBuffer
;
1740 mImageSize
= FileSize
;
1742 ZeroMem (&ImageContext
, sizeof (ImageContext
));
1743 ImageContext
.Handle
= (VOID
*) FileBuffer
;
1744 ImageContext
.ImageRead
= (PE_COFF_LOADER_READ_FILE
) DxeImageVerificationLibImageRead
;
1747 // Get information about the image being loaded
1749 PeCoffStatus
= PeCoffLoaderGetImageInfo (&ImageContext
);
1750 if (RETURN_ERROR (PeCoffStatus
)) {
1752 // The information can't be got from the invalid PeImage
1754 DEBUG ((DEBUG_INFO
, "DxeImageVerificationLib: PeImage invalid. Cannot retrieve image information.\n"));
1758 DosHdr
= (EFI_IMAGE_DOS_HEADER
*) mImageBase
;
1759 if (DosHdr
->e_magic
== EFI_IMAGE_DOS_SIGNATURE
) {
1761 // DOS image header is present,
1762 // so read the PE header after the DOS image header.
1764 mPeCoffHeaderOffset
= DosHdr
->e_lfanew
;
1766 mPeCoffHeaderOffset
= 0;
1769 // Check PE/COFF image.
1771 mNtHeader
.Pe32
= (EFI_IMAGE_NT_HEADERS32
*) (mImageBase
+ mPeCoffHeaderOffset
);
1772 if (mNtHeader
.Pe32
->Signature
!= EFI_IMAGE_NT_SIGNATURE
) {
1774 // It is not a valid Pe/Coff file.
1776 DEBUG ((DEBUG_INFO
, "DxeImageVerificationLib: Not a valid PE/COFF image.\n"));
1780 if (mNtHeader
.Pe32
->OptionalHeader
.Magic
== EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC
) {
1784 NumberOfRvaAndSizes
= mNtHeader
.Pe32
->OptionalHeader
.NumberOfRvaAndSizes
;
1785 if (NumberOfRvaAndSizes
> EFI_IMAGE_DIRECTORY_ENTRY_SECURITY
) {
1786 SecDataDir
= (EFI_IMAGE_DATA_DIRECTORY
*) &mNtHeader
.Pe32
->OptionalHeader
.DataDirectory
[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY
];
1790 // Use PE32+ offset.
1792 NumberOfRvaAndSizes
= mNtHeader
.Pe32Plus
->OptionalHeader
.NumberOfRvaAndSizes
;
1793 if (NumberOfRvaAndSizes
> EFI_IMAGE_DIRECTORY_ENTRY_SECURITY
) {
1794 SecDataDir
= (EFI_IMAGE_DATA_DIRECTORY
*) &mNtHeader
.Pe32Plus
->OptionalHeader
.DataDirectory
[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY
];
1799 // Start Image Validation.
1801 if (SecDataDir
== NULL
|| SecDataDir
->Size
== 0) {
1803 // This image is not signed. The SHA256 hash value of the image must match a record in the security database "db",
1804 // and not be reflected in the security data base "dbx".
1806 if (!HashPeImage (HASHALG_SHA256
)) {
1807 DEBUG ((DEBUG_INFO
, "DxeImageVerificationLib: Failed to hash this image using %s.\n", mHashTypeStr
));
1811 DbStatus
= IsSignatureFoundInDatabase (
1812 EFI_IMAGE_SECURITY_DATABASE1
,
1818 if (EFI_ERROR (DbStatus
) || IsFound
) {
1820 // Image Hash is in forbidden database (DBX).
1822 DEBUG ((DEBUG_INFO
, "DxeImageVerificationLib: Image is not signed and %s hash of image is forbidden by DBX.\n", mHashTypeStr
));
1826 DbStatus
= IsSignatureFoundInDatabase (
1827 EFI_IMAGE_SECURITY_DATABASE
,
1833 if (!EFI_ERROR (DbStatus
) && IsFound
) {
1835 // Image Hash is in allowed database (DB).
1841 // Image Hash is not found in both forbidden and allowed database.
1843 DEBUG ((DEBUG_INFO
, "DxeImageVerificationLib: Image is not signed and %s hash of image is not found in DB/DBX.\n", mHashTypeStr
));
1848 // Verify the signature of the image, multiple signatures are allowed as per PE/COFF Section 4.7
1849 // "Attribute Certificate Table".
1850 // The first certificate starts at offset (SecDataDir->VirtualAddress) from the start of the file.
1852 for (OffSet
= SecDataDir
->VirtualAddress
;
1853 OffSet
< (SecDataDir
->VirtualAddress
+ SecDataDir
->Size
);
1854 OffSet
+= (WinCertificate
->dwLength
+ ALIGN_SIZE (WinCertificate
->dwLength
))) {
1855 WinCertificate
= (WIN_CERTIFICATE
*) (mImageBase
+ OffSet
);
1856 if ((SecDataDir
->VirtualAddress
+ SecDataDir
->Size
- OffSet
) <= sizeof (WIN_CERTIFICATE
) ||
1857 (SecDataDir
->VirtualAddress
+ SecDataDir
->Size
- OffSet
) < WinCertificate
->dwLength
) {
1862 // Verify the image's Authenticode signature, only DER-encoded PKCS#7 signed data is supported.
1864 if (WinCertificate
->wCertificateType
== WIN_CERT_TYPE_PKCS_SIGNED_DATA
) {
1866 // The certificate is formatted as WIN_CERTIFICATE_EFI_PKCS which is described in the
1867 // Authenticode specification.
1869 PkcsCertData
= (WIN_CERTIFICATE_EFI_PKCS
*) WinCertificate
;
1870 if (PkcsCertData
->Hdr
.dwLength
<= sizeof (PkcsCertData
->Hdr
)) {
1873 AuthData
= PkcsCertData
->CertData
;
1874 AuthDataSize
= PkcsCertData
->Hdr
.dwLength
- sizeof(PkcsCertData
->Hdr
);
1875 } else if (WinCertificate
->wCertificateType
== WIN_CERT_TYPE_EFI_GUID
) {
1877 // The certificate is formatted as WIN_CERTIFICATE_UEFI_GUID which is described in UEFI Spec.
1879 WinCertUefiGuid
= (WIN_CERTIFICATE_UEFI_GUID
*) WinCertificate
;
1880 if (WinCertUefiGuid
->Hdr
.dwLength
<= OFFSET_OF(WIN_CERTIFICATE_UEFI_GUID
, CertData
)) {
1883 if (!CompareGuid (&WinCertUefiGuid
->CertType
, &gEfiCertPkcs7Guid
)) {
1886 AuthData
= WinCertUefiGuid
->CertData
;
1887 AuthDataSize
= WinCertUefiGuid
->Hdr
.dwLength
- OFFSET_OF(WIN_CERTIFICATE_UEFI_GUID
, CertData
);
1889 if (WinCertificate
->dwLength
< sizeof (WIN_CERTIFICATE
)) {
1895 HashStatus
= HashPeImageByType (AuthData
, AuthDataSize
);
1896 if (EFI_ERROR (HashStatus
)) {
1901 // Check the digital signature against the revoked certificate in forbidden database (dbx).
1903 if (IsForbiddenByDbx (AuthData
, AuthDataSize
)) {
1904 Action
= EFI_IMAGE_EXECUTION_AUTH_SIG_FAILED
;
1910 // Check the digital signature against the valid certificate in allowed database (db).
1913 if (IsAllowedByDb (AuthData
, AuthDataSize
)) {
1919 // Check the image's hash value.
1921 DbStatus
= IsSignatureFoundInDatabase (
1922 EFI_IMAGE_SECURITY_DATABASE1
,
1928 if (EFI_ERROR (DbStatus
) || IsFound
) {
1929 Action
= EFI_IMAGE_EXECUTION_AUTH_SIG_FOUND
;
1930 DEBUG ((DEBUG_INFO
, "DxeImageVerificationLib: Image is signed but %s hash of image is found in DBX.\n", mHashTypeStr
));
1936 DbStatus
= IsSignatureFoundInDatabase (
1937 EFI_IMAGE_SECURITY_DATABASE
,
1943 if (!EFI_ERROR (DbStatus
) && IsFound
) {
1946 DEBUG ((DEBUG_INFO
, "DxeImageVerificationLib: Image is signed but signature is not allowed by DB and %s hash of image is not found in DB/DBX.\n", mHashTypeStr
));
1951 if (OffSet
!= (SecDataDir
->VirtualAddress
+ SecDataDir
->Size
)) {
1953 // The Size in Certificate Table or the attribute certificate table is corrupted.
1961 if (Action
== EFI_IMAGE_EXECUTION_AUTH_SIG_FAILED
|| Action
== EFI_IMAGE_EXECUTION_AUTH_SIG_FOUND
) {
1963 // Get image hash value as signature of executable.
1965 SignatureListSize
= sizeof (EFI_SIGNATURE_LIST
) + sizeof (EFI_SIGNATURE_DATA
) - 1 + mImageDigestSize
;
1966 SignatureList
= (EFI_SIGNATURE_LIST
*) AllocateZeroPool (SignatureListSize
);
1967 if (SignatureList
== NULL
) {
1968 SignatureListSize
= 0;
1971 SignatureList
->SignatureHeaderSize
= 0;
1972 SignatureList
->SignatureListSize
= (UINT32
) SignatureListSize
;
1973 SignatureList
->SignatureSize
= (UINT32
) (sizeof (EFI_SIGNATURE_DATA
) - 1 + mImageDigestSize
);
1974 CopyMem (&SignatureList
->SignatureType
, &mCertType
, sizeof (EFI_GUID
));
1975 Signature
= (EFI_SIGNATURE_DATA
*) ((UINT8
*) SignatureList
+ sizeof (EFI_SIGNATURE_LIST
));
1976 CopyMem (Signature
->SignatureData
, mImageDigest
, mImageDigestSize
);
1981 // Policy decides to defer or reject the image; add its information in image
1982 // executable information table in either case.
1984 NameStr
= ConvertDevicePathToText (File
, FALSE
, TRUE
);
1985 AddImageExeInfo (Action
, NameStr
, File
, SignatureList
, SignatureListSize
);
1986 if (NameStr
!= NULL
) {
1987 DEBUG ((DEBUG_INFO
, "The image doesn't pass verification: %s\n", NameStr
));
1991 if (SignatureList
!= NULL
) {
1992 FreePool (SignatureList
);
1995 if (Policy
== DEFER_EXECUTE_ON_SECURITY_VIOLATION
) {
1996 return EFI_SECURITY_VIOLATION
;
1998 return EFI_ACCESS_DENIED
;
2002 On Ready To Boot Services Event notification handler.
2004 Add the image execution information table if it is not in system configuration table.
2006 @param[in] Event Event whose notification function is being invoked
2007 @param[in] Context Pointer to the notification function's context
2017 EFI_IMAGE_EXECUTION_INFO_TABLE
*ImageExeInfoTable
;
2018 UINTN ImageExeInfoTableSize
;
2020 EfiGetSystemConfigurationTable (&gEfiImageSecurityDatabaseGuid
, (VOID
**) &ImageExeInfoTable
);
2021 if (ImageExeInfoTable
!= NULL
) {
2025 ImageExeInfoTableSize
= sizeof (EFI_IMAGE_EXECUTION_INFO_TABLE
);
2026 ImageExeInfoTable
= (EFI_IMAGE_EXECUTION_INFO_TABLE
*) AllocateRuntimePool (ImageExeInfoTableSize
);
2027 if (ImageExeInfoTable
== NULL
) {
2031 ImageExeInfoTable
->NumberOfImages
= 0;
2032 gBS
->InstallConfigurationTable (&gEfiImageSecurityDatabaseGuid
, (VOID
*) ImageExeInfoTable
);
2037 Register security measurement handler.
2039 @param ImageHandle ImageHandle of the loaded driver.
2040 @param SystemTable Pointer to the EFI System Table.
2042 @retval EFI_SUCCESS The handlers were registered successfully.
2046 DxeImageVerificationLibConstructor (
2047 IN EFI_HANDLE ImageHandle
,
2048 IN EFI_SYSTEM_TABLE
*SystemTable
2054 // Register the event to publish the image execution table.
2056 EfiCreateEventReadyToBootEx (
2063 return RegisterSecurity2Handler (
2064 DxeImageVerificationHandler
,
2065 EFI_AUTH_OPERATION_VERIFY_IMAGE
| EFI_AUTH_OPERATION_IMAGE_REQUIRED