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 IsCertHashFoundInDatabase (
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.
959 @return TRUE Found the signature in the variable database.
960 @return FALSE Not found the signature in the variable database.
964 IsSignatureFoundInDatabase (
965 IN CHAR16
*VariableName
,
967 IN EFI_GUID
*CertType
,
968 IN UINTN SignatureSize
972 EFI_SIGNATURE_LIST
*CertList
;
973 EFI_SIGNATURE_DATA
*Cert
;
981 // Read signature database variable.
986 Status
= gRT
->GetVariable (VariableName
, &gEfiImageSecurityDatabaseGuid
, NULL
, &DataSize
, NULL
);
987 if (Status
!= EFI_BUFFER_TOO_SMALL
) {
991 Data
= (UINT8
*) AllocateZeroPool (DataSize
);
996 Status
= gRT
->GetVariable (VariableName
, &gEfiImageSecurityDatabaseGuid
, NULL
, &DataSize
, Data
);
997 if (EFI_ERROR (Status
)) {
1001 // Enumerate all signature data in SigDB to check if signature exists for executable.
1003 CertList
= (EFI_SIGNATURE_LIST
*) Data
;
1004 while ((DataSize
> 0) && (DataSize
>= CertList
->SignatureListSize
)) {
1005 CertCount
= (CertList
->SignatureListSize
- sizeof (EFI_SIGNATURE_LIST
) - CertList
->SignatureHeaderSize
) / CertList
->SignatureSize
;
1006 Cert
= (EFI_SIGNATURE_DATA
*) ((UINT8
*) CertList
+ sizeof (EFI_SIGNATURE_LIST
) + CertList
->SignatureHeaderSize
);
1007 if ((CertList
->SignatureSize
== sizeof(EFI_SIGNATURE_DATA
) - 1 + SignatureSize
) && (CompareGuid(&CertList
->SignatureType
, CertType
))) {
1008 for (Index
= 0; Index
< CertCount
; Index
++) {
1009 if (CompareMem (Cert
->SignatureData
, Signature
, SignatureSize
) == 0) {
1011 // Find the signature in database.
1015 // Entries in UEFI_IMAGE_SECURITY_DATABASE that are used to validate image should be measured
1017 if (StrCmp(VariableName
, EFI_IMAGE_SECURITY_DATABASE
) == 0) {
1018 SecureBootHook (VariableName
, &gEfiImageSecurityDatabaseGuid
, CertList
->SignatureSize
, Cert
);
1023 Cert
= (EFI_SIGNATURE_DATA
*) ((UINT8
*) Cert
+ CertList
->SignatureSize
);
1031 DataSize
-= CertList
->SignatureListSize
;
1032 CertList
= (EFI_SIGNATURE_LIST
*) ((UINT8
*) CertList
+ CertList
->SignatureListSize
);
1044 Check whether the timestamp is valid by comparing the signing time and the revocation time.
1046 @param SigningTime A pointer to the signing time.
1047 @param RevocationTime A pointer to the revocation time.
1049 @retval TRUE The SigningTime is not later than the RevocationTime.
1050 @retval FALSE The SigningTime is later than the RevocationTime.
1054 IsValidSignatureByTimestamp (
1055 IN EFI_TIME
*SigningTime
,
1056 IN EFI_TIME
*RevocationTime
1059 if (SigningTime
->Year
!= RevocationTime
->Year
) {
1060 return (BOOLEAN
) (SigningTime
->Year
< RevocationTime
->Year
);
1061 } else if (SigningTime
->Month
!= RevocationTime
->Month
) {
1062 return (BOOLEAN
) (SigningTime
->Month
< RevocationTime
->Month
);
1063 } else if (SigningTime
->Day
!= RevocationTime
->Day
) {
1064 return (BOOLEAN
) (SigningTime
->Day
< RevocationTime
->Day
);
1065 } else if (SigningTime
->Hour
!= RevocationTime
->Hour
) {
1066 return (BOOLEAN
) (SigningTime
->Hour
< RevocationTime
->Hour
);
1067 } else if (SigningTime
->Minute
!= RevocationTime
->Minute
) {
1068 return (BOOLEAN
) (SigningTime
->Minute
< RevocationTime
->Minute
);
1071 return (BOOLEAN
) (SigningTime
->Second
<= RevocationTime
->Second
);
1075 Check if the given time value is zero.
1077 @param[in] Time Pointer of a time value.
1079 @retval TRUE The Time is Zero.
1080 @retval FALSE The Time is not Zero.
1088 if ((Time
->Year
== 0) && (Time
->Month
== 0) && (Time
->Day
== 0) &&
1089 (Time
->Hour
== 0) && (Time
->Minute
== 0) && (Time
->Second
== 0)) {
1097 Check whether the timestamp signature is valid and the signing time is also earlier than
1098 the revocation time.
1100 @param[in] AuthData Pointer to the Authenticode signature retrieved from signed image.
1101 @param[in] AuthDataSize Size of the Authenticode signature in bytes.
1102 @param[in] RevocationTime The time that the certificate was revoked.
1104 @retval TRUE Timestamp signature is valid and signing time is no later than the
1106 @retval FALSE Timestamp signature is not valid or the signing time is later than the
1111 PassTimestampCheck (
1113 IN UINTN AuthDataSize
,
1114 IN EFI_TIME
*RevocationTime
1118 BOOLEAN VerifyStatus
;
1119 EFI_SIGNATURE_LIST
*CertList
;
1120 EFI_SIGNATURE_DATA
*Cert
;
1127 EFI_TIME SigningTime
;
1130 // Variable Initialization
1132 VerifyStatus
= FALSE
;
1140 // If RevocationTime is zero, the certificate shall be considered to always be revoked.
1142 if (IsTimeZero (RevocationTime
)) {
1147 // RevocationTime is non-zero, the certificate should be considered to be revoked from that time and onwards.
1148 // Using the dbt to get the trusted TSA certificates.
1151 Status
= gRT
->GetVariable (EFI_IMAGE_SECURITY_DATABASE2
, &gEfiImageSecurityDatabaseGuid
, NULL
, &DbtDataSize
, NULL
);
1152 if (Status
!= EFI_BUFFER_TOO_SMALL
) {
1155 DbtData
= (UINT8
*) AllocateZeroPool (DbtDataSize
);
1156 if (DbtData
== NULL
) {
1159 Status
= gRT
->GetVariable (EFI_IMAGE_SECURITY_DATABASE2
, &gEfiImageSecurityDatabaseGuid
, NULL
, &DbtDataSize
, (VOID
*) DbtData
);
1160 if (EFI_ERROR (Status
)) {
1164 CertList
= (EFI_SIGNATURE_LIST
*) DbtData
;
1165 while ((DbtDataSize
> 0) && (DbtDataSize
>= CertList
->SignatureListSize
)) {
1166 if (CompareGuid (&CertList
->SignatureType
, &gEfiCertX509Guid
)) {
1167 Cert
= (EFI_SIGNATURE_DATA
*) ((UINT8
*) CertList
+ sizeof (EFI_SIGNATURE_LIST
) + CertList
->SignatureHeaderSize
);
1168 CertCount
= (CertList
->SignatureListSize
- sizeof (EFI_SIGNATURE_LIST
) - CertList
->SignatureHeaderSize
) / CertList
->SignatureSize
;
1169 for (Index
= 0; Index
< CertCount
; Index
++) {
1171 // Iterate each Signature Data Node within this CertList for verify.
1173 RootCert
= Cert
->SignatureData
;
1174 RootCertSize
= CertList
->SignatureSize
- sizeof (EFI_GUID
);
1176 // Get the signing time if the timestamp signature is valid.
1178 if (ImageTimestampVerify (AuthData
, AuthDataSize
, RootCert
, RootCertSize
, &SigningTime
)) {
1180 // The signer signature is valid only when the signing time is earlier than revocation time.
1182 if (IsValidSignatureByTimestamp (&SigningTime
, RevocationTime
)) {
1183 VerifyStatus
= TRUE
;
1187 Cert
= (EFI_SIGNATURE_DATA
*) ((UINT8
*) Cert
+ CertList
->SignatureSize
);
1190 DbtDataSize
-= CertList
->SignatureListSize
;
1191 CertList
= (EFI_SIGNATURE_LIST
*) ((UINT8
*) CertList
+ CertList
->SignatureListSize
);
1195 if (DbtData
!= NULL
) {
1199 return VerifyStatus
;
1203 Check whether the image signature is forbidden by the forbidden database (dbx).
1204 The image is forbidden to load if any certificates for signing are revoked before signing time.
1206 @param[in] AuthData Pointer to the Authenticode signature retrieved from the signed image.
1207 @param[in] AuthDataSize Size of the Authenticode signature in bytes.
1209 @retval TRUE Image is forbidden by dbx.
1210 @retval FALSE Image is not forbidden by dbx.
1216 IN UINTN AuthDataSize
1220 BOOLEAN IsForbidden
;
1224 EFI_SIGNATURE_LIST
*CertList
;
1226 EFI_SIGNATURE_DATA
*CertData
;
1234 UINTN TrustedCertLength
;
1239 EFI_TIME RevocationTime
;
1241 // Variable Initialization
1253 TrustedCertLength
= 0;
1256 // The image will not be forbidden if dbx can't be got.
1259 Status
= gRT
->GetVariable (EFI_IMAGE_SECURITY_DATABASE1
, &gEfiImageSecurityDatabaseGuid
, NULL
, &DataSize
, NULL
);
1260 ASSERT (EFI_ERROR (Status
));
1261 if (Status
!= EFI_BUFFER_TOO_SMALL
) {
1262 if (Status
== EFI_NOT_FOUND
) {
1264 // Evidently not in dbx if the database doesn't exist.
1266 IsForbidden
= FALSE
;
1270 Data
= (UINT8
*) AllocateZeroPool (DataSize
);
1275 Status
= gRT
->GetVariable (EFI_IMAGE_SECURITY_DATABASE1
, &gEfiImageSecurityDatabaseGuid
, NULL
, &DataSize
, (VOID
*) Data
);
1276 if (EFI_ERROR (Status
)) {
1281 // Verify image signature with RAW X509 certificates in DBX database.
1282 // If passed, the image will be forbidden.
1284 CertList
= (EFI_SIGNATURE_LIST
*) Data
;
1285 CertListSize
= DataSize
;
1286 while ((CertListSize
> 0) && (CertListSize
>= CertList
->SignatureListSize
)) {
1287 if (CompareGuid (&CertList
->SignatureType
, &gEfiCertX509Guid
)) {
1288 CertData
= (EFI_SIGNATURE_DATA
*) ((UINT8
*) CertList
+ sizeof (EFI_SIGNATURE_LIST
) + CertList
->SignatureHeaderSize
);
1289 CertCount
= (CertList
->SignatureListSize
- sizeof (EFI_SIGNATURE_LIST
) - CertList
->SignatureHeaderSize
) / CertList
->SignatureSize
;
1291 for (Index
= 0; Index
< CertCount
; Index
++) {
1293 // Iterate each Signature Data Node within this CertList for verify.
1295 RootCert
= CertData
->SignatureData
;
1296 RootCertSize
= CertList
->SignatureSize
- sizeof (EFI_GUID
);
1299 // Call AuthenticodeVerify library to Verify Authenticode struct.
1301 IsForbidden
= AuthenticodeVerify (
1310 DEBUG ((DEBUG_INFO
, "DxeImageVerificationLib: Image is signed but signature is forbidden by DBX.\n"));
1314 CertData
= (EFI_SIGNATURE_DATA
*) ((UINT8
*) CertData
+ CertList
->SignatureSize
);
1318 CertListSize
-= CertList
->SignatureListSize
;
1319 CertList
= (EFI_SIGNATURE_LIST
*) ((UINT8
*) CertList
+ CertList
->SignatureListSize
);
1323 // Check X.509 Certificate Hash & Possible Timestamp.
1327 // Retrieve the certificate stack from AuthData
1328 // The output CertStack format will be:
1329 // UINT8 CertNumber;
1330 // UINT32 Cert1Length;
1332 // UINT32 Cert2Length;
1335 // UINT32 CertnLength;
1338 Pkcs7GetSigners (AuthData
, AuthDataSize
, &CertBuffer
, &BufferLength
, &TrustedCert
, &TrustedCertLength
);
1339 if ((BufferLength
== 0) || (CertBuffer
== NULL
) || (*CertBuffer
) == 0) {
1345 // Check if any hash of certificates embedded in AuthData is in the forbidden database.
1347 CertNumber
= (UINT8
) (*CertBuffer
);
1348 CertPtr
= CertBuffer
+ 1;
1349 for (Index
= 0; Index
< CertNumber
; Index
++) {
1350 CertSize
= (UINTN
) ReadUnaligned32 ((UINT32
*)CertPtr
);
1351 Cert
= (UINT8
*)CertPtr
+ sizeof (UINT32
);
1353 // Advance CertPtr to the next cert in image signer's cert list
1355 CertPtr
= CertPtr
+ sizeof (UINT32
) + CertSize
;
1357 Status
= IsCertHashFoundInDatabase (Cert
, CertSize
, (EFI_SIGNATURE_LIST
*)Data
, DataSize
, &RevocationTime
, &IsFound
);
1358 if (EFI_ERROR (Status
)) {
1360 // Error in searching dbx. Consider it as 'found'. RevocationTime might
1361 // not be valid in such situation.
1364 } else if (IsFound
) {
1366 // Found Cert in dbx successfully. Check the timestamp signature and
1367 // signing time to determine if the image can be trusted.
1369 if (PassTimestampCheck (AuthData
, AuthDataSize
, &RevocationTime
)) {
1370 IsForbidden
= FALSE
;
1372 // Pass DBT check. Continue to check other certs in image signer's cert list against DBX, DBT
1377 DEBUG ((DEBUG_INFO
, "DxeImageVerificationLib: Image is signed but signature failed the timestamp check.\n"));
1384 IsForbidden
= FALSE
;
1391 Pkcs7FreeSigners (CertBuffer
);
1392 Pkcs7FreeSigners (TrustedCert
);
1399 Check whether the image signature can be verified by the trusted certificates in DB database.
1401 @param[in] AuthData Pointer to the Authenticode signature retrieved from signed image.
1402 @param[in] AuthDataSize Size of the Authenticode signature in bytes.
1404 @retval TRUE Image passed verification using certificate in db.
1405 @retval FALSE Image didn't pass verification using certificate in db.
1411 IN UINTN AuthDataSize
1415 BOOLEAN VerifyStatus
;
1417 EFI_SIGNATURE_LIST
*CertList
;
1418 EFI_SIGNATURE_DATA
*CertData
;
1427 EFI_TIME RevocationTime
;
1435 VerifyStatus
= FALSE
;
1438 // Fetch 'db' content. If 'db' doesn't exist or encounters problem to get the
1439 // data, return not-allowed-by-db (FALSE).
1442 Status
= gRT
->GetVariable (EFI_IMAGE_SECURITY_DATABASE
, &gEfiImageSecurityDatabaseGuid
, NULL
, &DataSize
, NULL
);
1443 ASSERT (EFI_ERROR (Status
));
1444 if (Status
!= EFI_BUFFER_TOO_SMALL
) {
1445 return VerifyStatus
;
1448 Data
= (UINT8
*) AllocateZeroPool (DataSize
);
1450 return VerifyStatus
;
1453 Status
= gRT
->GetVariable (EFI_IMAGE_SECURITY_DATABASE
, &gEfiImageSecurityDatabaseGuid
, NULL
, &DataSize
, (VOID
*) Data
);
1454 if (EFI_ERROR (Status
)) {
1459 // Fetch 'dbx' content. If 'dbx' doesn't exist, continue to check 'db'.
1460 // If any other errors occured, no need to check 'db' but just return
1461 // not-allowed-by-db (FALSE) to avoid bypass.
1464 Status
= gRT
->GetVariable (EFI_IMAGE_SECURITY_DATABASE1
, &gEfiImageSecurityDatabaseGuid
, NULL
, &DbxDataSize
, NULL
);
1465 ASSERT (EFI_ERROR (Status
));
1466 if (Status
!= EFI_BUFFER_TOO_SMALL
) {
1467 if (Status
!= EFI_NOT_FOUND
) {
1471 // 'dbx' does not exist. Continue to check 'db'.
1475 // 'dbx' exists. Get its content.
1477 DbxData
= (UINT8
*) AllocateZeroPool (DbxDataSize
);
1478 if (DbxData
== NULL
) {
1482 Status
= gRT
->GetVariable (EFI_IMAGE_SECURITY_DATABASE1
, &gEfiImageSecurityDatabaseGuid
, NULL
, &DbxDataSize
, (VOID
*) DbxData
);
1483 if (EFI_ERROR (Status
)) {
1489 // Find X509 certificate in Signature List to verify the signature in pkcs7 signed data.
1491 CertList
= (EFI_SIGNATURE_LIST
*) Data
;
1492 while ((DataSize
> 0) && (DataSize
>= CertList
->SignatureListSize
)) {
1493 if (CompareGuid (&CertList
->SignatureType
, &gEfiCertX509Guid
)) {
1494 CertData
= (EFI_SIGNATURE_DATA
*) ((UINT8
*) CertList
+ sizeof (EFI_SIGNATURE_LIST
) + CertList
->SignatureHeaderSize
);
1495 CertCount
= (CertList
->SignatureListSize
- sizeof (EFI_SIGNATURE_LIST
) - CertList
->SignatureHeaderSize
) / CertList
->SignatureSize
;
1497 for (Index
= 0; Index
< CertCount
; Index
++) {
1499 // Iterate each Signature Data Node within this CertList for verify.
1501 RootCert
= CertData
->SignatureData
;
1502 RootCertSize
= CertList
->SignatureSize
- sizeof (EFI_GUID
);
1505 // Call AuthenticodeVerify library to Verify Authenticode struct.
1507 VerifyStatus
= AuthenticodeVerify (
1517 // The image is signed and its signature is found in 'db'.
1519 if (DbxData
!= NULL
) {
1521 // Here We still need to check if this RootCert's Hash is revoked
1523 Status
= IsCertHashFoundInDatabase (RootCert
, RootCertSize
, (EFI_SIGNATURE_LIST
*)DbxData
, DbxDataSize
, &RevocationTime
, &IsFound
);
1524 if (EFI_ERROR (Status
)) {
1526 // Error in searching dbx. Consider it as 'found'. RevocationTime might
1527 // not be valid in such situation.
1529 VerifyStatus
= FALSE
;
1530 } else if (IsFound
) {
1532 // Check the timestamp signature and signing time to determine if the RootCert can be trusted.
1534 VerifyStatus
= PassTimestampCheck (AuthData
, AuthDataSize
, &RevocationTime
);
1535 if (!VerifyStatus
) {
1536 DEBUG ((DEBUG_INFO
, "DxeImageVerificationLib: Image is signed and signature is accepted by DB, but its root cert failed the timestamp check.\n"));
1542 // There's no 'dbx' to check revocation time against (must-be pass),
1543 // or, there's revocation time found in 'dbx' and checked againt 'dbt'
1544 // (maybe pass or fail, depending on timestamp compare result). Either
1545 // way the verification job has been completed at this point.
1550 CertData
= (EFI_SIGNATURE_DATA
*) ((UINT8
*) CertData
+ CertList
->SignatureSize
);
1554 DataSize
-= CertList
->SignatureListSize
;
1555 CertList
= (EFI_SIGNATURE_LIST
*) ((UINT8
*) CertList
+ CertList
->SignatureListSize
);
1561 SecureBootHook (EFI_IMAGE_SECURITY_DATABASE
, &gEfiImageSecurityDatabaseGuid
, CertList
->SignatureSize
, CertData
);
1567 if (DbxData
!= NULL
) {
1571 return VerifyStatus
;
1575 Provide verification service for signed images, which include both signature validation
1576 and platform policy control. For signature types, both UEFI WIN_CERTIFICATE_UEFI_GUID and
1577 MSFT Authenticode type signatures are supported.
1579 In this implementation, only verify external executables when in USER MODE.
1580 Executables from FV is bypass, so pass in AuthenticationStatus is ignored.
1582 The image verification policy is:
1583 If the image is signed,
1584 At least one valid signature or at least one hash value of the image must match a record
1585 in the security database "db", and no valid signature nor any hash value of the image may
1586 be reflected in the security database "dbx".
1587 Otherwise, the image is not signed,
1588 The SHA256 hash value of the image must match a record in the security database "db", and
1589 not be reflected in the security data base "dbx".
1591 Caution: This function may receive untrusted input.
1592 PE/COFF image is external input, so this function will validate its data structure
1593 within this image buffer before use.
1595 @param[in] AuthenticationStatus
1596 This is the authentication status returned from the security
1597 measurement services for the input file.
1598 @param[in] File This is a pointer to the device path of the file that is
1599 being dispatched. This will optionally be used for logging.
1600 @param[in] FileBuffer File buffer matches the input file device path.
1601 @param[in] FileSize Size of File buffer matches the input file device path.
1602 @param[in] BootPolicy A boot policy that was used to call LoadImage() UEFI service.
1604 @retval EFI_SUCCESS The file specified by DevicePath and non-NULL
1605 FileBuffer did authenticate, and the platform policy dictates
1606 that the DXE Foundation may use the file.
1607 @retval EFI_SUCCESS The device path specified by NULL device path DevicePath
1608 and non-NULL FileBuffer did authenticate, and the platform
1609 policy dictates that the DXE Foundation may execute the image in
1611 @retval EFI_SECURITY_VIOLATION The file specified by File did not authenticate, and
1612 the platform policy dictates that File should be placed
1613 in the untrusted state. The image has been added to the file
1615 @retval EFI_ACCESS_DENIED The file specified by File and FileBuffer did not
1616 authenticate, and the platform policy dictates that the DXE
1617 Foundation may not use File. The image has
1618 been added to the file execution table.
1623 DxeImageVerificationHandler (
1624 IN UINT32 AuthenticationStatus
,
1625 IN CONST EFI_DEVICE_PATH_PROTOCOL
*File
,
1626 IN VOID
*FileBuffer
,
1628 IN BOOLEAN BootPolicy
1631 EFI_IMAGE_DOS_HEADER
*DosHdr
;
1633 EFI_SIGNATURE_LIST
*SignatureList
;
1634 UINTN SignatureListSize
;
1635 EFI_SIGNATURE_DATA
*Signature
;
1636 EFI_IMAGE_EXECUTION_ACTION Action
;
1637 WIN_CERTIFICATE
*WinCertificate
;
1640 PE_COFF_LOADER_IMAGE_CONTEXT ImageContext
;
1641 UINT32 NumberOfRvaAndSizes
;
1642 WIN_CERTIFICATE_EFI_PKCS
*PkcsCertData
;
1643 WIN_CERTIFICATE_UEFI_GUID
*WinCertUefiGuid
;
1646 EFI_IMAGE_DATA_DIRECTORY
*SecDataDir
;
1649 RETURN_STATUS PeCoffStatus
;
1650 EFI_STATUS HashStatus
;
1652 SignatureList
= NULL
;
1653 SignatureListSize
= 0;
1654 WinCertificate
= NULL
;
1656 PkcsCertData
= NULL
;
1657 Action
= EFI_IMAGE_EXECUTION_AUTH_UNTESTED
;
1662 // Check the image type and get policy setting.
1664 switch (GetImageType (File
)) {
1667 Policy
= ALWAYS_EXECUTE
;
1670 case IMAGE_FROM_OPTION_ROM
:
1671 Policy
= PcdGet32 (PcdOptionRomImageVerificationPolicy
);
1674 case IMAGE_FROM_REMOVABLE_MEDIA
:
1675 Policy
= PcdGet32 (PcdRemovableMediaImageVerificationPolicy
);
1678 case IMAGE_FROM_FIXED_MEDIA
:
1679 Policy
= PcdGet32 (PcdFixedMediaImageVerificationPolicy
);
1683 Policy
= DENY_EXECUTE_ON_SECURITY_VIOLATION
;
1687 // If policy is always/never execute, return directly.
1689 if (Policy
== ALWAYS_EXECUTE
) {
1692 if (Policy
== NEVER_EXECUTE
) {
1693 return EFI_ACCESS_DENIED
;
1697 // The policy QUERY_USER_ON_SECURITY_VIOLATION and ALLOW_EXECUTE_ON_SECURITY_VIOLATION
1698 // violates the UEFI spec and has been removed.
1700 ASSERT (Policy
!= QUERY_USER_ON_SECURITY_VIOLATION
&& Policy
!= ALLOW_EXECUTE_ON_SECURITY_VIOLATION
);
1701 if (Policy
== QUERY_USER_ON_SECURITY_VIOLATION
|| Policy
== ALLOW_EXECUTE_ON_SECURITY_VIOLATION
) {
1705 GetEfiGlobalVariable2 (EFI_SECURE_BOOT_MODE_NAME
, (VOID
**)&SecureBoot
, NULL
);
1707 // Skip verification if SecureBoot variable doesn't exist.
1709 if (SecureBoot
== NULL
) {
1714 // Skip verification if SecureBoot is disabled but not AuditMode
1716 if (*SecureBoot
== SECURE_BOOT_MODE_DISABLE
) {
1717 FreePool (SecureBoot
);
1720 FreePool (SecureBoot
);
1723 // Read the Dos header.
1725 if (FileBuffer
== NULL
) {
1726 return EFI_ACCESS_DENIED
;
1729 mImageBase
= (UINT8
*) FileBuffer
;
1730 mImageSize
= FileSize
;
1732 ZeroMem (&ImageContext
, sizeof (ImageContext
));
1733 ImageContext
.Handle
= (VOID
*) FileBuffer
;
1734 ImageContext
.ImageRead
= (PE_COFF_LOADER_READ_FILE
) DxeImageVerificationLibImageRead
;
1737 // Get information about the image being loaded
1739 PeCoffStatus
= PeCoffLoaderGetImageInfo (&ImageContext
);
1740 if (RETURN_ERROR (PeCoffStatus
)) {
1742 // The information can't be got from the invalid PeImage
1744 DEBUG ((DEBUG_INFO
, "DxeImageVerificationLib: PeImage invalid. Cannot retrieve image information.\n"));
1748 DosHdr
= (EFI_IMAGE_DOS_HEADER
*) mImageBase
;
1749 if (DosHdr
->e_magic
== EFI_IMAGE_DOS_SIGNATURE
) {
1751 // DOS image header is present,
1752 // so read the PE header after the DOS image header.
1754 mPeCoffHeaderOffset
= DosHdr
->e_lfanew
;
1756 mPeCoffHeaderOffset
= 0;
1759 // Check PE/COFF image.
1761 mNtHeader
.Pe32
= (EFI_IMAGE_NT_HEADERS32
*) (mImageBase
+ mPeCoffHeaderOffset
);
1762 if (mNtHeader
.Pe32
->Signature
!= EFI_IMAGE_NT_SIGNATURE
) {
1764 // It is not a valid Pe/Coff file.
1766 DEBUG ((DEBUG_INFO
, "DxeImageVerificationLib: Not a valid PE/COFF image.\n"));
1770 if (mNtHeader
.Pe32
->OptionalHeader
.Magic
== EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC
) {
1774 NumberOfRvaAndSizes
= mNtHeader
.Pe32
->OptionalHeader
.NumberOfRvaAndSizes
;
1775 if (NumberOfRvaAndSizes
> EFI_IMAGE_DIRECTORY_ENTRY_SECURITY
) {
1776 SecDataDir
= (EFI_IMAGE_DATA_DIRECTORY
*) &mNtHeader
.Pe32
->OptionalHeader
.DataDirectory
[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY
];
1780 // Use PE32+ offset.
1782 NumberOfRvaAndSizes
= mNtHeader
.Pe32Plus
->OptionalHeader
.NumberOfRvaAndSizes
;
1783 if (NumberOfRvaAndSizes
> EFI_IMAGE_DIRECTORY_ENTRY_SECURITY
) {
1784 SecDataDir
= (EFI_IMAGE_DATA_DIRECTORY
*) &mNtHeader
.Pe32Plus
->OptionalHeader
.DataDirectory
[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY
];
1789 // Start Image Validation.
1791 if (SecDataDir
== NULL
|| SecDataDir
->Size
== 0) {
1793 // This image is not signed. The SHA256 hash value of the image must match a record in the security database "db",
1794 // and not be reflected in the security data base "dbx".
1796 if (!HashPeImage (HASHALG_SHA256
)) {
1797 DEBUG ((DEBUG_INFO
, "DxeImageVerificationLib: Failed to hash this image using %s.\n", mHashTypeStr
));
1801 if (IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE1
, mImageDigest
, &mCertType
, mImageDigestSize
)) {
1803 // Image Hash is in forbidden database (DBX).
1805 DEBUG ((DEBUG_INFO
, "DxeImageVerificationLib: Image is not signed and %s hash of image is forbidden by DBX.\n", mHashTypeStr
));
1809 if (IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE
, mImageDigest
, &mCertType
, mImageDigestSize
)) {
1811 // Image Hash is in allowed database (DB).
1817 // Image Hash is not found in both forbidden and allowed database.
1819 DEBUG ((DEBUG_INFO
, "DxeImageVerificationLib: Image is not signed and %s hash of image is not found in DB/DBX.\n", mHashTypeStr
));
1824 // Verify the signature of the image, multiple signatures are allowed as per PE/COFF Section 4.7
1825 // "Attribute Certificate Table".
1826 // The first certificate starts at offset (SecDataDir->VirtualAddress) from the start of the file.
1828 for (OffSet
= SecDataDir
->VirtualAddress
;
1829 OffSet
< (SecDataDir
->VirtualAddress
+ SecDataDir
->Size
);
1830 OffSet
+= (WinCertificate
->dwLength
+ ALIGN_SIZE (WinCertificate
->dwLength
))) {
1831 WinCertificate
= (WIN_CERTIFICATE
*) (mImageBase
+ OffSet
);
1832 if ((SecDataDir
->VirtualAddress
+ SecDataDir
->Size
- OffSet
) <= sizeof (WIN_CERTIFICATE
) ||
1833 (SecDataDir
->VirtualAddress
+ SecDataDir
->Size
- OffSet
) < WinCertificate
->dwLength
) {
1838 // Verify the image's Authenticode signature, only DER-encoded PKCS#7 signed data is supported.
1840 if (WinCertificate
->wCertificateType
== WIN_CERT_TYPE_PKCS_SIGNED_DATA
) {
1842 // The certificate is formatted as WIN_CERTIFICATE_EFI_PKCS which is described in the
1843 // Authenticode specification.
1845 PkcsCertData
= (WIN_CERTIFICATE_EFI_PKCS
*) WinCertificate
;
1846 if (PkcsCertData
->Hdr
.dwLength
<= sizeof (PkcsCertData
->Hdr
)) {
1849 AuthData
= PkcsCertData
->CertData
;
1850 AuthDataSize
= PkcsCertData
->Hdr
.dwLength
- sizeof(PkcsCertData
->Hdr
);
1851 } else if (WinCertificate
->wCertificateType
== WIN_CERT_TYPE_EFI_GUID
) {
1853 // The certificate is formatted as WIN_CERTIFICATE_UEFI_GUID which is described in UEFI Spec.
1855 WinCertUefiGuid
= (WIN_CERTIFICATE_UEFI_GUID
*) WinCertificate
;
1856 if (WinCertUefiGuid
->Hdr
.dwLength
<= OFFSET_OF(WIN_CERTIFICATE_UEFI_GUID
, CertData
)) {
1859 if (!CompareGuid (&WinCertUefiGuid
->CertType
, &gEfiCertPkcs7Guid
)) {
1862 AuthData
= WinCertUefiGuid
->CertData
;
1863 AuthDataSize
= WinCertUefiGuid
->Hdr
.dwLength
- OFFSET_OF(WIN_CERTIFICATE_UEFI_GUID
, CertData
);
1865 if (WinCertificate
->dwLength
< sizeof (WIN_CERTIFICATE
)) {
1871 HashStatus
= HashPeImageByType (AuthData
, AuthDataSize
);
1872 if (EFI_ERROR (HashStatus
)) {
1877 // Check the digital signature against the revoked certificate in forbidden database (dbx).
1879 if (IsForbiddenByDbx (AuthData
, AuthDataSize
)) {
1880 Action
= EFI_IMAGE_EXECUTION_AUTH_SIG_FAILED
;
1886 // Check the digital signature against the valid certificate in allowed database (db).
1889 if (IsAllowedByDb (AuthData
, AuthDataSize
)) {
1895 // Check the image's hash value.
1897 if (IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE1
, mImageDigest
, &mCertType
, mImageDigestSize
)) {
1898 Action
= EFI_IMAGE_EXECUTION_AUTH_SIG_FOUND
;
1899 DEBUG ((DEBUG_INFO
, "DxeImageVerificationLib: Image is signed but %s hash of image is found in DBX.\n", mHashTypeStr
));
1904 if (IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE
, mImageDigest
, &mCertType
, mImageDigestSize
)) {
1907 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
));
1912 if (OffSet
!= (SecDataDir
->VirtualAddress
+ SecDataDir
->Size
)) {
1914 // The Size in Certificate Table or the attribute certificate table is corrupted.
1922 if (Action
== EFI_IMAGE_EXECUTION_AUTH_SIG_FAILED
|| Action
== EFI_IMAGE_EXECUTION_AUTH_SIG_FOUND
) {
1924 // Get image hash value as signature of executable.
1926 SignatureListSize
= sizeof (EFI_SIGNATURE_LIST
) + sizeof (EFI_SIGNATURE_DATA
) - 1 + mImageDigestSize
;
1927 SignatureList
= (EFI_SIGNATURE_LIST
*) AllocateZeroPool (SignatureListSize
);
1928 if (SignatureList
== NULL
) {
1929 SignatureListSize
= 0;
1932 SignatureList
->SignatureHeaderSize
= 0;
1933 SignatureList
->SignatureListSize
= (UINT32
) SignatureListSize
;
1934 SignatureList
->SignatureSize
= (UINT32
) (sizeof (EFI_SIGNATURE_DATA
) - 1 + mImageDigestSize
);
1935 CopyMem (&SignatureList
->SignatureType
, &mCertType
, sizeof (EFI_GUID
));
1936 Signature
= (EFI_SIGNATURE_DATA
*) ((UINT8
*) SignatureList
+ sizeof (EFI_SIGNATURE_LIST
));
1937 CopyMem (Signature
->SignatureData
, mImageDigest
, mImageDigestSize
);
1942 // Policy decides to defer or reject the image; add its information in image
1943 // executable information table in either case.
1945 NameStr
= ConvertDevicePathToText (File
, FALSE
, TRUE
);
1946 AddImageExeInfo (Action
, NameStr
, File
, SignatureList
, SignatureListSize
);
1947 if (NameStr
!= NULL
) {
1948 DEBUG ((DEBUG_INFO
, "The image doesn't pass verification: %s\n", NameStr
));
1952 if (SignatureList
!= NULL
) {
1953 FreePool (SignatureList
);
1956 if (Policy
== DEFER_EXECUTE_ON_SECURITY_VIOLATION
) {
1957 return EFI_SECURITY_VIOLATION
;
1959 return EFI_ACCESS_DENIED
;
1963 On Ready To Boot Services Event notification handler.
1965 Add the image execution information table if it is not in system configuration table.
1967 @param[in] Event Event whose notification function is being invoked
1968 @param[in] Context Pointer to the notification function's context
1978 EFI_IMAGE_EXECUTION_INFO_TABLE
*ImageExeInfoTable
;
1979 UINTN ImageExeInfoTableSize
;
1981 EfiGetSystemConfigurationTable (&gEfiImageSecurityDatabaseGuid
, (VOID
**) &ImageExeInfoTable
);
1982 if (ImageExeInfoTable
!= NULL
) {
1986 ImageExeInfoTableSize
= sizeof (EFI_IMAGE_EXECUTION_INFO_TABLE
);
1987 ImageExeInfoTable
= (EFI_IMAGE_EXECUTION_INFO_TABLE
*) AllocateRuntimePool (ImageExeInfoTableSize
);
1988 if (ImageExeInfoTable
== NULL
) {
1992 ImageExeInfoTable
->NumberOfImages
= 0;
1993 gBS
->InstallConfigurationTable (&gEfiImageSecurityDatabaseGuid
, (VOID
*) ImageExeInfoTable
);
1998 Register security measurement handler.
2000 @param ImageHandle ImageHandle of the loaded driver.
2001 @param SystemTable Pointer to the EFI System Table.
2003 @retval EFI_SUCCESS The handlers were registered successfully.
2007 DxeImageVerificationLibConstructor (
2008 IN EFI_HANDLE ImageHandle
,
2009 IN EFI_SYSTEM_TABLE
*SystemTable
2015 // Register the event to publish the image execution table.
2017 EfiCreateEventReadyToBootEx (
2024 return RegisterSecurity2Handler (
2025 DxeImageVerificationHandler
,
2026 EFI_AUTH_OPERATION_VERIFY_IMAGE
| EFI_AUTH_OPERATION_IMAGE_REQUIRED