X-Git-Url: https://git.proxmox.com/?p=mirror_edk2.git;a=blobdiff_plain;f=SecurityPkg%2FLibrary%2FDxeImageVerificationLib%2FDxeImageVerificationLib.c;h=66d96a9396b9137cd4a7bb3367c82affc9f59389;hp=c86ce1f312ae5c7543e4ea356863fb9c81b08c64;hb=f199664ce70b6b1303329113bf9fbc9b002fa1b6;hpb=5db28a6753d307cdfb1cfdeb2f63739a9f959837
diff --git a/SecurityPkg/Library/DxeImageVerificationLib/DxeImageVerificationLib.c b/SecurityPkg/Library/DxeImageVerificationLib/DxeImageVerificationLib.c
index c86ce1f312..66d96a9396 100644
--- a/SecurityPkg/Library/DxeImageVerificationLib/DxeImageVerificationLib.c
+++ b/SecurityPkg/Library/DxeImageVerificationLib/DxeImageVerificationLib.c
@@ -1,5 +1,5 @@
/** @file
- Implement image verification services for secure boot service in UEFI2.3.1.
+ Implement image verification services for secure boot service
Caution: This file requires additional review when modified.
This library will have external input - PE/COFF image.
@@ -12,7 +12,8 @@
DxeImageVerificationHandler(), HashPeImageByType(), HashPeImage() function will accept
untrusted PE/COFF image and validate its data structure within this image buffer before use.
-Copyright (c) 2009 - 2012, Intel Corporation. All rights reserved.
+Copyright (c) 2009 - 2018, Intel Corporation. All rights reserved.
+(C) Copyright 2016 Hewlett Packard Enterprise Development LP
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
@@ -31,7 +32,6 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
//
EFI_IMAGE_OPTIONAL_HEADER_PTR_UNION mNtHeader;
UINT32 mPeCoffHeaderOffset;
-EFI_IMAGE_DATA_DIRECTORY *mSecDataDir = NULL;
EFI_GUID mCertType;
//
@@ -57,7 +57,6 @@ CONST UINT8 mRsaE[] = { 0x01, 0x00, 0x01 };
// OID ASN.1 Value for Hash Algorithms
//
UINT8 mHashOidValue[] = {
- 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x02, 0x05, // OBJ_md5
0x2B, 0x0E, 0x03, 0x02, 0x1A, // OBJ_sha1
0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04, // OBJ_sha224
0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, // OBJ_sha256
@@ -66,13 +65,34 @@ UINT8 mHashOidValue[] = {
};
HASH_TABLE mHash[] = {
- { L"SHA1", 20, &mHashOidValue[8], 5, Sha1GetContextSize, Sha1Init, Sha1Update, Sha1Final },
- { L"SHA224", 28, &mHashOidValue[13], 9, NULL, NULL, NULL, NULL },
- { L"SHA256", 32, &mHashOidValue[22], 9, Sha256GetContextSize,Sha256Init, Sha256Update, Sha256Final},
- { L"SHA384", 48, &mHashOidValue[31], 9, NULL, NULL, NULL, NULL },
- { L"SHA512", 64, &mHashOidValue[40], 9, NULL, NULL, NULL, NULL }
+ { L"SHA1", 20, &mHashOidValue[0], 5, Sha1GetContextSize, Sha1Init, Sha1Update, Sha1Final },
+ { L"SHA224", 28, &mHashOidValue[5], 9, NULL, NULL, NULL, NULL },
+ { L"SHA256", 32, &mHashOidValue[14], 9, Sha256GetContextSize, Sha256Init, Sha256Update, Sha256Final},
+ { L"SHA384", 48, &mHashOidValue[23], 9, Sha384GetContextSize, Sha384Init, Sha384Update, Sha384Final},
+ { L"SHA512", 64, &mHashOidValue[32], 9, Sha512GetContextSize, Sha512Init, Sha512Update, Sha512Final}
};
+EFI_STRING mHashTypeStr;
+
+/**
+ SecureBoot Hook for processing image verification.
+
+ @param[in] VariableName Name of Variable to be found.
+ @param[in] VendorGuid Variable vendor GUID.
+ @param[in] DataSize Size of Data found. If size is less than the
+ data, this value contains the required size.
+ @param[in] Data Data pointer.
+
+**/
+VOID
+EFIAPI
+SecureBootHook (
+ IN CHAR16 *VariableName,
+ IN EFI_GUID *VendorGuid,
+ IN UINTN DataSize,
+ IN VOID *Data
+ );
+
/**
Reads contents of a PE/COFF image in memory buffer.
@@ -82,11 +102,11 @@ HASH_TABLE mHash[] = {
@param FileHandle Pointer to the file handle to read the PE/COFF image.
@param FileOffset Offset into the PE/COFF image to begin the read operation.
- @param ReadSize On input, the size in bytes of the requested read operation.
+ @param ReadSize On input, the size in bytes of the requested read operation.
On output, the number of bytes actually read.
@param Buffer Output buffer that contains the data read from the PE/COFF image.
-
- @retval EFI_SUCCESS The specified portion of the PE/COFF image was read and the size
+
+ @retval EFI_SUCCESS The specified portion of the PE/COFF image was read and the size
**/
EFI_STATUS
EFIAPI
@@ -100,7 +120,7 @@ DxeImageVerificationLibImageRead (
UINTN EndPosition;
if (FileHandle == NULL || ReadSize == NULL || Buffer == NULL) {
- return EFI_INVALID_PARAMETER;
+ return EFI_INVALID_PARAMETER;
}
if (MAX_ADDRESS - FileOffset < *ReadSize) {
@@ -253,13 +273,16 @@ GetImageType (
}
/**
- Caculate hash of Pe/Coff image based on the authenticode image hashing in
+ Calculate hash of Pe/Coff image based on the authenticode image hashing in
PE/COFF Specification 8.0 Appendix A
Caution: This function may receive untrusted input.
PE/COFF image is external input, so this function will validate its data structure
within this image buffer before use.
+ Notes: PE/COFF image has been checked by BasePeCoffLib PeCoffLoaderGetImageInfo() in
+ its caller function DxeImageVerificationHandler().
+
@param[in] HashAlg Hash algorithm type.
@retval TRUE Successfully hash image.
@@ -272,7 +295,6 @@ HashPeImage (
)
{
BOOLEAN Status;
- UINT16 Magic;
EFI_IMAGE_SECTION_HEADER *Section;
VOID *HashCtx;
UINTN CtxSize;
@@ -289,7 +311,7 @@ HashPeImage (
SectionHeader = NULL;
Status = FALSE;
- if ((HashAlg != HASHALG_SHA1) && (HashAlg != HASHALG_SHA256)) {
+ if ((HashAlg >= HASHALG_MAX)) {
return FALSE;
}
@@ -298,16 +320,32 @@ HashPeImage (
//
ZeroMem (mImageDigest, MAX_DIGEST_SIZE);
- if (HashAlg == HASHALG_SHA1) {
- mImageDigestSize = SHA1_DIGEST_SIZE;
- mCertType = gEfiCertSha1Guid;
- } else if (HashAlg == HASHALG_SHA256) {
- mImageDigestSize = SHA256_DIGEST_SIZE;
- mCertType = gEfiCertSha256Guid;
- } else {
+ switch (HashAlg) {
+ case HASHALG_SHA1:
+ mImageDigestSize = SHA1_DIGEST_SIZE;
+ mCertType = gEfiCertSha1Guid;
+ break;
+
+ case HASHALG_SHA256:
+ mImageDigestSize = SHA256_DIGEST_SIZE;
+ mCertType = gEfiCertSha256Guid;
+ break;
+
+ case HASHALG_SHA384:
+ mImageDigestSize = SHA384_DIGEST_SIZE;
+ mCertType = gEfiCertSha384Guid;
+ break;
+
+ case HASHALG_SHA512:
+ mImageDigestSize = SHA512_DIGEST_SIZE;
+ mCertType = gEfiCertSha512Guid;
+ break;
+
+ default:
return FALSE;
}
+ mHashTypeStr = mHash[HashAlg].Name;
CtxSize = mHash[HashAlg].GetContextSize();
HashCtx = AllocatePool (CtxSize);
@@ -328,37 +366,23 @@ HashPeImage (
// Measuring PE/COFF Image Header;
// But CheckSum field and SECURITY data directory (certificate) are excluded
//
- if (mNtHeader.Pe32->FileHeader.Machine == IMAGE_FILE_MACHINE_IA64 && mNtHeader.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
- //
- // NOTE: Some versions of Linux ELILO for Itanium have an incorrect magic value
- // in the PE/COFF Header. If the MachineType is Itanium(IA64) and the
- // Magic value in the OptionalHeader is EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC
- // then override the magic value to EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC
- //
- Magic = EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC;
- } else {
- //
- // Get the magic value from the PE/COFF Optional Header
- //
- Magic = mNtHeader.Pe32->OptionalHeader.Magic;
- }
-
+
//
// 3. Calculate the distance from the base of the image header to the image checksum address.
// 4. Hash the image header from its base to beginning of the image checksum.
//
HashBase = mImageBase;
- if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
+ if (mNtHeader.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
- HashSize = (UINTN) ((UINT8 *) (&mNtHeader.Pe32->OptionalHeader.CheckSum) - HashBase);
+ HashSize = (UINTN) (&mNtHeader.Pe32->OptionalHeader.CheckSum) - (UINTN) HashBase;
NumberOfRvaAndSizes = mNtHeader.Pe32->OptionalHeader.NumberOfRvaAndSizes;
- } else if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC) {
+ } else if (mNtHeader.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC) {
//
// Use PE32+ offset.
//
- HashSize = (UINTN) ((UINT8 *) (&mNtHeader.Pe32Plus->OptionalHeader.CheckSum) - HashBase);
+ HashSize = (UINTN) (&mNtHeader.Pe32Plus->OptionalHeader.CheckSum) - (UINTN) HashBase;
NumberOfRvaAndSizes = mNtHeader.Pe32Plus->OptionalHeader.NumberOfRvaAndSizes;
} else {
//
@@ -381,18 +405,18 @@ HashPeImage (
// 6. Since there is no Cert Directory in optional header, hash everything
// from the end of the checksum to the end of image header.
//
- if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
+ if (mNtHeader.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
HashBase = (UINT8 *) &mNtHeader.Pe32->OptionalHeader.CheckSum + sizeof (UINT32);
- HashSize = mNtHeader.Pe32->OptionalHeader.SizeOfHeaders - (UINTN) (HashBase - mImageBase);
+ HashSize = mNtHeader.Pe32->OptionalHeader.SizeOfHeaders - ((UINTN) HashBase - (UINTN) mImageBase);
} else {
//
// Use PE32+ offset.
//
HashBase = (UINT8 *) &mNtHeader.Pe32Plus->OptionalHeader.CheckSum + sizeof (UINT32);
- HashSize = mNtHeader.Pe32Plus->OptionalHeader.SizeOfHeaders - (UINTN) (HashBase - mImageBase);
+ HashSize = mNtHeader.Pe32Plus->OptionalHeader.SizeOfHeaders - ((UINTN) HashBase - (UINTN) mImageBase);
}
if (HashSize != 0) {
@@ -405,18 +429,18 @@ HashPeImage (
//
// 7. Hash everything from the end of the checksum to the start of the Cert Directory.
//
- if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
+ if (mNtHeader.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
HashBase = (UINT8 *) &mNtHeader.Pe32->OptionalHeader.CheckSum + sizeof (UINT32);
- HashSize = (UINTN) ((UINT8 *) (&mNtHeader.Pe32->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY]) - HashBase);
+ HashSize = (UINTN) (&mNtHeader.Pe32->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY]) - (UINTN) HashBase;
} else {
//
// Use PE32+ offset.
//
HashBase = (UINT8 *) &mNtHeader.Pe32Plus->OptionalHeader.CheckSum + sizeof (UINT32);
- HashSize = (UINTN) ((UINT8 *) (&mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY]) - HashBase);
+ HashSize = (UINTN) (&mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY]) - (UINTN) HashBase;
}
if (HashSize != 0) {
@@ -430,18 +454,18 @@ HashPeImage (
// 8. Skip over the Cert Directory. (It is sizeof(IMAGE_DATA_DIRECTORY) bytes.)
// 9. Hash everything from the end of the Cert Directory to the end of image header.
//
- if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
+ if (mNtHeader.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset
//
HashBase = (UINT8 *) &mNtHeader.Pe32->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY + 1];
- HashSize = mNtHeader.Pe32->OptionalHeader.SizeOfHeaders - (UINTN) (HashBase - mImageBase);
+ HashSize = mNtHeader.Pe32->OptionalHeader.SizeOfHeaders - ((UINTN) HashBase - (UINTN) mImageBase);
} else {
//
// Use PE32+ offset.
//
HashBase = (UINT8 *) &mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY + 1];
- HashSize = mNtHeader.Pe32Plus->OptionalHeader.SizeOfHeaders - (UINTN) (HashBase - mImageBase);
+ HashSize = mNtHeader.Pe32Plus->OptionalHeader.SizeOfHeaders - ((UINTN) HashBase - (UINTN) mImageBase);
}
if (HashSize != 0) {
@@ -449,13 +473,13 @@ HashPeImage (
if (!Status) {
goto Done;
}
- }
+ }
}
//
// 10. Set the SUM_OF_BYTES_HASHED to the size of the header.
//
- if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
+ if (mNtHeader.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
@@ -538,7 +562,7 @@ HashPeImage (
if (NumberOfRvaAndSizes <= EFI_IMAGE_DIRECTORY_ENTRY_SECURITY) {
CertSize = 0;
} else {
- if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
+ if (mNtHeader.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
@@ -577,7 +601,7 @@ Done:
}
/**
- Recognize the Hash algorithm in PE/COFF Authenticode and caculate hash of
+ Recognize the Hash algorithm in PE/COFF Authenticode and calculate hash of
Pe/Coff image based on the authenticode image hashing in PE/COFF Specification
8.0 Appendix A
@@ -585,23 +609,20 @@ Done:
PE/COFF image is external input, so this function will validate its data structure
within this image buffer before use.
+ @param[in] AuthData Pointer to the Authenticode Signature retrieved from signed image.
+ @param[in] AuthDataSize Size of the Authenticode Signature in bytes.
+
@retval EFI_UNSUPPORTED Hash algorithm is not supported.
@retval EFI_SUCCESS Hash successfully.
**/
EFI_STATUS
HashPeImageByType (
- VOID
+ IN UINT8 *AuthData,
+ IN UINTN AuthDataSize
)
{
UINT8 Index;
- WIN_CERTIFICATE_EFI_PKCS *PkcsCertData;
-
- PkcsCertData = (WIN_CERTIFICATE_EFI_PKCS *) (mImageBase + mSecDataDir->VirtualAddress);
-
- if (PkcsCertData->Hdr.dwLength < sizeof (WIN_CERTIFICATE_EFI_PKCS) + 32) {
- return EFI_UNSUPPORTED;
- }
for (Index = 0; Index < HASHALG_MAX; Index++) {
//
@@ -616,18 +637,18 @@ HashPeImageByType (
// This field has the fixed offset (+32) in final Authenticode ASN.1 data.
// Fixed offset (+32) is calculated based on two bytes of length encoding.
//
- if ((*(PkcsCertData->CertData + 1) & TWO_BYTE_ENCODE) != TWO_BYTE_ENCODE) {
+ if ((*(AuthData + 1) & TWO_BYTE_ENCODE) != TWO_BYTE_ENCODE) {
//
// Only support two bytes of Long Form of Length Encoding.
//
continue;
}
- if (PkcsCertData->Hdr.dwLength < sizeof (WIN_CERTIFICATE_EFI_PKCS) + 32 + mHash[Index].OidLength) {
+ if (AuthDataSize < 32 + mHash[Index].OidLength) {
return EFI_UNSUPPORTED;
}
- if (CompareMem (PkcsCertData->CertData + 32, mHash[Index].OidValue, mHash[Index].OidLength) == 0) {
+ if (CompareMem (AuthData + 32, mHash[Index].OidValue, mHash[Index].OidLength) == 0) {
break;
}
}
@@ -708,11 +729,13 @@ AddImageExeInfo (
UINTN NewImageExeInfoEntrySize;
UINTN NameStringLen;
UINTN DevicePathSize;
+ CHAR16 *NameStr;
ImageExeInfoTable = NULL;
NewImageExeInfoTable = NULL;
ImageExeInfoEntry = NULL;
NameStringLen = 0;
+ NameStr = NULL;
if (DevicePath == NULL) {
return ;
@@ -720,14 +743,15 @@ AddImageExeInfo (
if (Name != NULL) {
NameStringLen = StrSize (Name);
+ } else {
+ NameStringLen = sizeof (CHAR16);
}
- ImageExeInfoTable = NULL;
EfiGetSystemConfigurationTable (&gEfiImageSecurityDatabaseGuid, (VOID **) &ImageExeInfoTable);
if (ImageExeInfoTable != NULL) {
//
// The table has been found!
- // We must enlarge the table to accmodate the new exe info entry.
+ // We must enlarge the table to accomodate the new exe info entry.
//
ImageExeInfoTableSize = GetImageExeInfoTableSize (ImageExeInfoTable);
} else {
@@ -739,7 +763,12 @@ AddImageExeInfo (
}
DevicePathSize = GetDevicePathSize (DevicePath);
- NewImageExeInfoEntrySize = sizeof (EFI_IMAGE_EXECUTION_INFO) + NameStringLen + DevicePathSize + SignatureSize;
+
+ //
+ // Signature size can be odd. Pad after signature to ensure next EXECUTION_INFO entry align
+ //
+ NewImageExeInfoEntrySize = sizeof (EFI_IMAGE_EXECUTION_INFO) + NameStringLen + DevicePathSize + SignatureSize;
+
NewImageExeInfoTable = (EFI_IMAGE_EXECUTION_INFO_TABLE *) AllocateRuntimePool (ImageExeInfoTableSize + NewImageExeInfoEntrySize);
if (NewImageExeInfoTable == NULL) {
return ;
@@ -753,22 +782,26 @@ AddImageExeInfo (
NewImageExeInfoTable->NumberOfImages++;
ImageExeInfoEntry = (EFI_IMAGE_EXECUTION_INFO *) ((UINT8 *) NewImageExeInfoTable + ImageExeInfoTableSize);
//
- // Update new item's infomation.
+ // Update new item's information.
//
- WriteUnaligned32 ((UINT32 *) &ImageExeInfoEntry->Action, Action);
- WriteUnaligned32 ((UINT32 *) &ImageExeInfoEntry->InfoSize, (UINT32) NewImageExeInfoEntrySize);
+ WriteUnaligned32 ((UINT32 *) ImageExeInfoEntry, Action);
+ WriteUnaligned32 ((UINT32 *) ((UINT8 *) ImageExeInfoEntry + sizeof (EFI_IMAGE_EXECUTION_ACTION)), (UINT32) NewImageExeInfoEntrySize);
+ NameStr = (CHAR16 *)(ImageExeInfoEntry + 1);
if (Name != NULL) {
- CopyMem ((UINT8 *) &ImageExeInfoEntry->InfoSize + sizeof (UINT32), Name, NameStringLen);
+ CopyMem ((UINT8 *) NameStr, Name, NameStringLen);
+ } else {
+ ZeroMem ((UINT8 *) NameStr, sizeof (CHAR16));
}
+
CopyMem (
- (UINT8 *) &ImageExeInfoEntry->InfoSize + sizeof (UINT32) + NameStringLen,
+ (UINT8 *) NameStr + NameStringLen,
DevicePath,
DevicePathSize
);
if (Signature != NULL) {
CopyMem (
- (UINT8 *) &ImageExeInfoEntry->InfoSize + sizeof (UINT32) + NameStringLen + DevicePathSize,
+ (UINT8 *) NameStr + NameStringLen + DevicePathSize,
Signature,
SignatureSize
);
@@ -786,6 +819,135 @@ AddImageExeInfo (
}
}
+/**
+ Check whether the hash of an given X.509 certificate is in forbidden database (DBX).
+
+ @param[in] Certificate Pointer to X.509 Certificate that is searched for.
+ @param[in] CertSize Size of X.509 Certificate.
+ @param[in] SignatureList Pointer to the Signature List in forbidden database.
+ @param[in] SignatureListSize Size of Signature List.
+ @param[out] RevocationTime Return the time that the certificate was revoked.
+
+ @return TRUE The certificate hash is found in the forbidden database.
+ @return FALSE The certificate hash is not found in the forbidden database.
+
+**/
+BOOLEAN
+IsCertHashFoundInDatabase (
+ IN UINT8 *Certificate,
+ IN UINTN CertSize,
+ IN EFI_SIGNATURE_LIST *SignatureList,
+ IN UINTN SignatureListSize,
+ OUT EFI_TIME *RevocationTime
+ )
+{
+ BOOLEAN IsFound;
+ BOOLEAN Status;
+ EFI_SIGNATURE_LIST *DbxList;
+ UINTN DbxSize;
+ EFI_SIGNATURE_DATA *CertHash;
+ UINTN CertHashCount;
+ UINTN Index;
+ UINT32 HashAlg;
+ VOID *HashCtx;
+ UINT8 CertDigest[MAX_DIGEST_SIZE];
+ UINT8 *DbxCertHash;
+ UINTN SiglistHeaderSize;
+ UINT8 *TBSCert;
+ UINTN TBSCertSize;
+
+ IsFound = FALSE;
+ DbxList = SignatureList;
+ DbxSize = SignatureListSize;
+ HashCtx = NULL;
+ HashAlg = HASHALG_MAX;
+
+ if ((RevocationTime == NULL) || (DbxList == NULL)) {
+ return FALSE;
+ }
+
+ //
+ // Retrieve the TBSCertificate from the X.509 Certificate.
+ //
+ if (!X509GetTBSCert (Certificate, CertSize, &TBSCert, &TBSCertSize)) {
+ return FALSE;
+ }
+
+ while ((DbxSize > 0) && (SignatureListSize >= DbxList->SignatureListSize)) {
+ //
+ // Determine Hash Algorithm of Certificate in the forbidden database.
+ //
+ if (CompareGuid (&DbxList->SignatureType, &gEfiCertX509Sha256Guid)) {
+ HashAlg = HASHALG_SHA256;
+ } else if (CompareGuid (&DbxList->SignatureType, &gEfiCertX509Sha384Guid)) {
+ HashAlg = HASHALG_SHA384;
+ } else if (CompareGuid (&DbxList->SignatureType, &gEfiCertX509Sha512Guid)) {
+ HashAlg = HASHALG_SHA512;
+ } else {
+ DbxSize -= DbxList->SignatureListSize;
+ DbxList = (EFI_SIGNATURE_LIST *) ((UINT8 *) DbxList + DbxList->SignatureListSize);
+ continue;
+ }
+
+ //
+ // Calculate the hash value of current TBSCertificate for comparision.
+ //
+ if (mHash[HashAlg].GetContextSize == NULL) {
+ goto Done;
+ }
+ ZeroMem (CertDigest, MAX_DIGEST_SIZE);
+ HashCtx = AllocatePool (mHash[HashAlg].GetContextSize ());
+ if (HashCtx == NULL) {
+ goto Done;
+ }
+ Status = mHash[HashAlg].HashInit (HashCtx);
+ if (!Status) {
+ goto Done;
+ }
+ Status = mHash[HashAlg].HashUpdate (HashCtx, TBSCert, TBSCertSize);
+ if (!Status) {
+ goto Done;
+ }
+ Status = mHash[HashAlg].HashFinal (HashCtx, CertDigest);
+ if (!Status) {
+ goto Done;
+ }
+
+ SiglistHeaderSize = sizeof (EFI_SIGNATURE_LIST) + DbxList->SignatureHeaderSize;
+ CertHash = (EFI_SIGNATURE_DATA *) ((UINT8 *) DbxList + SiglistHeaderSize);
+ CertHashCount = (DbxList->SignatureListSize - SiglistHeaderSize) / DbxList->SignatureSize;
+ for (Index = 0; Index < CertHashCount; Index++) {
+ //
+ // Iterate each Signature Data Node within this CertList for verify.
+ //
+ DbxCertHash = CertHash->SignatureData;
+ if (CompareMem (DbxCertHash, CertDigest, mHash[HashAlg].DigestLength) == 0) {
+ //
+ // Hash of Certificate is found in forbidden database.
+ //
+ IsFound = TRUE;
+
+ //
+ // Return the revocation time.
+ //
+ CopyMem (RevocationTime, (EFI_TIME *)(DbxCertHash + mHash[HashAlg].DigestLength), sizeof (EFI_TIME));
+ goto Done;
+ }
+ CertHash = (EFI_SIGNATURE_DATA *) ((UINT8 *) CertHash + DbxList->SignatureSize);
+ }
+
+ DbxSize -= DbxList->SignatureListSize;
+ DbxList = (EFI_SIGNATURE_LIST *) ((UINT8 *) DbxList + DbxList->SignatureListSize);
+ }
+
+Done:
+ if (HashCtx != NULL) {
+ FreePool (HashCtx);
+ }
+
+ return IsFound;
+}
+
/**
Check whether signature is in specified database.
@@ -814,6 +976,7 @@ IsSignatureFoundInDatabase (
UINTN Index;
UINTN CertCount;
BOOLEAN IsFound;
+
//
// Read signature database variable.
//
@@ -839,7 +1002,7 @@ IsSignatureFoundInDatabase (
//
CertList = (EFI_SIGNATURE_LIST *) Data;
while ((DataSize > 0) && (DataSize >= CertList->SignatureListSize)) {
- CertCount = (CertList->SignatureListSize - CertList->SignatureHeaderSize) / CertList->SignatureSize;
+ CertCount = (CertList->SignatureListSize - sizeof (EFI_SIGNATURE_LIST) - CertList->SignatureHeaderSize) / CertList->SignatureSize;
Cert = (EFI_SIGNATURE_DATA *) ((UINT8 *) CertList + sizeof (EFI_SIGNATURE_LIST) + CertList->SignatureHeaderSize);
if ((CertList->SignatureSize == sizeof(EFI_SIGNATURE_DATA) - 1 + SignatureSize) && (CompareGuid(&CertList->SignatureType, CertType))) {
for (Index = 0; Index < CertCount; Index++) {
@@ -848,6 +1011,12 @@ IsSignatureFoundInDatabase (
// Find the signature in database.
//
IsFound = TRUE;
+ //
+ // Entries in UEFI_IMAGE_SECURITY_DATABASE that are used to validate image should be measured
+ //
+ if (StrCmp(VariableName, EFI_IMAGE_SECURITY_DATABASE) == 0) {
+ SecureBootHook (VariableName, &gEfiImageSecurityDatabaseGuid, CertList->SignatureSize, Cert);
+ }
break;
}
@@ -872,51 +1041,388 @@ Done:
}
/**
- Verify PKCS#7 SignedData using certificate found in Variable which formatted
- as EFI_SIGNATURE_LIST. The Variable may be PK, KEK, DB or DBX.
+ Check whether the timestamp is valid by comparing the signing time and the revocation time.
- @param VariableName Name of Variable to search for Certificate.
- @param VendorGuid Variable vendor GUID.
+ @param SigningTime A pointer to the signing time.
+ @param RevocationTime A pointer to the revocation time.
- @retval TRUE Image pass verification.
- @retval FALSE Image fail verification.
+ @retval TRUE The SigningTime is not later than the RevocationTime.
+ @retval FALSE The SigningTime is later than the RevocationTime.
**/
BOOLEAN
-IsPkcsSignedDataVerifiedBySignatureList (
- IN CHAR16 *VariableName,
- IN EFI_GUID *VendorGuid
+IsValidSignatureByTimestamp (
+ IN EFI_TIME *SigningTime,
+ IN EFI_TIME *RevocationTime
+ )
+{
+ if (SigningTime->Year != RevocationTime->Year) {
+ return (BOOLEAN) (SigningTime->Year < RevocationTime->Year);
+ } else if (SigningTime->Month != RevocationTime->Month) {
+ return (BOOLEAN) (SigningTime->Month < RevocationTime->Month);
+ } else if (SigningTime->Day != RevocationTime->Day) {
+ return (BOOLEAN) (SigningTime->Day < RevocationTime->Day);
+ } else if (SigningTime->Hour != RevocationTime->Hour) {
+ return (BOOLEAN) (SigningTime->Hour < RevocationTime->Hour);
+ } else if (SigningTime->Minute != RevocationTime->Minute) {
+ return (BOOLEAN) (SigningTime->Minute < RevocationTime->Minute);
+ }
+
+ return (BOOLEAN) (SigningTime->Second <= RevocationTime->Second);
+}
+
+/**
+ Check if the given time value is zero.
+
+ @param[in] Time Pointer of a time value.
+
+ @retval TRUE The Time is Zero.
+ @retval FALSE The Time is not Zero.
+
+**/
+BOOLEAN
+IsTimeZero (
+ IN EFI_TIME *Time
+ )
+{
+ if ((Time->Year == 0) && (Time->Month == 0) && (Time->Day == 0) &&
+ (Time->Hour == 0) && (Time->Minute == 0) && (Time->Second == 0)) {
+ return TRUE;
+ }
+
+ return FALSE;
+}
+
+/**
+ Check whether the timestamp signature is valid and the signing time is also earlier than
+ the revocation time.
+
+ @param[in] AuthData Pointer to the Authenticode signature retrieved from signed image.
+ @param[in] AuthDataSize Size of the Authenticode signature in bytes.
+ @param[in] RevocationTime The time that the certificate was revoked.
+
+ @retval TRUE Timestamp signature is valid and signing time is no later than the
+ revocation time.
+ @retval FALSE Timestamp signature is not valid or the signing time is later than the
+ revocation time.
+
+**/
+BOOLEAN
+PassTimestampCheck (
+ IN UINT8 *AuthData,
+ IN UINTN AuthDataSize,
+ IN EFI_TIME *RevocationTime
)
{
EFI_STATUS Status;
BOOLEAN VerifyStatus;
- WIN_CERTIFICATE_EFI_PKCS *PkcsCertData;
EFI_SIGNATURE_LIST *CertList;
EFI_SIGNATURE_DATA *Cert;
+ UINT8 *DbtData;
+ UINTN DbtDataSize;
+ UINT8 *RootCert;
+ UINTN RootCertSize;
+ UINTN Index;
+ UINTN CertCount;
+ EFI_TIME SigningTime;
+
+ //
+ // Variable Initialization
+ //
+ VerifyStatus = FALSE;
+ DbtData = NULL;
+ CertList = NULL;
+ Cert = NULL;
+ RootCert = NULL;
+ RootCertSize = 0;
+
+ //
+ // If RevocationTime is zero, the certificate shall be considered to always be revoked.
+ //
+ if (IsTimeZero (RevocationTime)) {
+ return FALSE;
+ }
+
+ //
+ // RevocationTime is non-zero, the certificate should be considered to be revoked from that time and onwards.
+ // Using the dbt to get the trusted TSA certificates.
+ //
+ DbtDataSize = 0;
+ Status = gRT->GetVariable (EFI_IMAGE_SECURITY_DATABASE2, &gEfiImageSecurityDatabaseGuid, NULL, &DbtDataSize, NULL);
+ if (Status != EFI_BUFFER_TOO_SMALL) {
+ goto Done;
+ }
+ DbtData = (UINT8 *) AllocateZeroPool (DbtDataSize);
+ if (DbtData == NULL) {
+ goto Done;
+ }
+ Status = gRT->GetVariable (EFI_IMAGE_SECURITY_DATABASE2, &gEfiImageSecurityDatabaseGuid, NULL, &DbtDataSize, (VOID *) DbtData);
+ if (EFI_ERROR (Status)) {
+ goto Done;
+ }
+
+ CertList = (EFI_SIGNATURE_LIST *) DbtData;
+ while ((DbtDataSize > 0) && (DbtDataSize >= CertList->SignatureListSize)) {
+ if (CompareGuid (&CertList->SignatureType, &gEfiCertX509Guid)) {
+ Cert = (EFI_SIGNATURE_DATA *) ((UINT8 *) CertList + sizeof (EFI_SIGNATURE_LIST) + CertList->SignatureHeaderSize);
+ CertCount = (CertList->SignatureListSize - sizeof (EFI_SIGNATURE_LIST) - CertList->SignatureHeaderSize) / CertList->SignatureSize;
+ for (Index = 0; Index < CertCount; Index++) {
+ //
+ // Iterate each Signature Data Node within this CertList for verify.
+ //
+ RootCert = Cert->SignatureData;
+ RootCertSize = CertList->SignatureSize - sizeof (EFI_GUID);
+ //
+ // Get the signing time if the timestamp signature is valid.
+ //
+ if (ImageTimestampVerify (AuthData, AuthDataSize, RootCert, RootCertSize, &SigningTime)) {
+ //
+ // The signer signature is valid only when the signing time is earlier than revocation time.
+ //
+ if (IsValidSignatureByTimestamp (&SigningTime, RevocationTime)) {
+ VerifyStatus = TRUE;
+ goto Done;
+ }
+ }
+ Cert = (EFI_SIGNATURE_DATA *) ((UINT8 *) Cert + CertList->SignatureSize);
+ }
+ }
+ DbtDataSize -= CertList->SignatureListSize;
+ CertList = (EFI_SIGNATURE_LIST *) ((UINT8 *) CertList + CertList->SignatureListSize);
+ }
+
+Done:
+ if (DbtData != NULL) {
+ FreePool (DbtData);
+ }
+
+ return VerifyStatus;
+}
+
+/**
+ Check whether the image signature is forbidden by the forbidden database (dbx).
+ The image is forbidden to load if any certificates for signing are revoked before signing time.
+
+ @param[in] AuthData Pointer to the Authenticode signature retrieved from the signed image.
+ @param[in] AuthDataSize Size of the Authenticode signature in bytes.
+
+ @retval TRUE Image is forbidden by dbx.
+ @retval FALSE Image is not forbidden by dbx.
+
+**/
+BOOLEAN
+IsForbiddenByDbx (
+ IN UINT8 *AuthData,
+ IN UINTN AuthDataSize
+ )
+{
+ EFI_STATUS Status;
+ BOOLEAN IsForbidden;
+ UINT8 *Data;
+ UINTN DataSize;
+ EFI_SIGNATURE_LIST *CertList;
+ UINTN CertListSize;
+ EFI_SIGNATURE_DATA *CertData;
+ UINT8 *RootCert;
+ UINTN RootCertSize;
+ UINTN CertCount;
+ UINTN Index;
+ UINT8 *CertBuffer;
+ UINTN BufferLength;
+ UINT8 *TrustedCert;
+ UINTN TrustedCertLength;
+ UINT8 CertNumber;
+ UINT8 *CertPtr;
+ UINT8 *Cert;
+ UINTN CertSize;
+ EFI_TIME RevocationTime;
+ //
+ // Variable Initialization
+ //
+ IsForbidden = FALSE;
+ Data = NULL;
+ CertList = NULL;
+ CertData = NULL;
+ RootCert = NULL;
+ RootCertSize = 0;
+ Cert = NULL;
+ CertBuffer = NULL;
+ BufferLength = 0;
+ TrustedCert = NULL;
+ TrustedCertLength = 0;
+
+ //
+ // The image will not be forbidden if dbx can't be got.
+ //
+ DataSize = 0;
+ Status = gRT->GetVariable (EFI_IMAGE_SECURITY_DATABASE1, &gEfiImageSecurityDatabaseGuid, NULL, &DataSize, NULL);
+ if (Status != EFI_BUFFER_TOO_SMALL) {
+ return IsForbidden;
+ }
+ Data = (UINT8 *) AllocateZeroPool (DataSize);
+ if (Data == NULL) {
+ return IsForbidden;
+ }
+
+ Status = gRT->GetVariable (EFI_IMAGE_SECURITY_DATABASE1, &gEfiImageSecurityDatabaseGuid, NULL, &DataSize, (VOID *) Data);
+ if (EFI_ERROR (Status)) {
+ return IsForbidden;
+ }
+
+ //
+ // Verify image signature with RAW X509 certificates in DBX database.
+ // If passed, the image will be forbidden.
+ //
+ CertList = (EFI_SIGNATURE_LIST *) Data;
+ CertListSize = DataSize;
+ while ((CertListSize > 0) && (CertListSize >= CertList->SignatureListSize)) {
+ if (CompareGuid (&CertList->SignatureType, &gEfiCertX509Guid)) {
+ CertData = (EFI_SIGNATURE_DATA *) ((UINT8 *) CertList + sizeof (EFI_SIGNATURE_LIST) + CertList->SignatureHeaderSize);
+ CertCount = (CertList->SignatureListSize - sizeof (EFI_SIGNATURE_LIST) - CertList->SignatureHeaderSize) / CertList->SignatureSize;
+
+ for (Index = 0; Index < CertCount; Index++) {
+ //
+ // Iterate each Signature Data Node within this CertList for verify.
+ //
+ RootCert = CertData->SignatureData;
+ RootCertSize = CertList->SignatureSize - sizeof (EFI_GUID);
+
+ //
+ // Call AuthenticodeVerify library to Verify Authenticode struct.
+ //
+ IsForbidden = AuthenticodeVerify (
+ AuthData,
+ AuthDataSize,
+ RootCert,
+ RootCertSize,
+ mImageDigest,
+ mImageDigestSize
+ );
+ if (IsForbidden) {
+ DEBUG ((DEBUG_INFO, "DxeImageVerificationLib: Image is signed but signature is forbidden by DBX.\n"));
+ goto Done;
+ }
+
+ CertData = (EFI_SIGNATURE_DATA *) ((UINT8 *) CertData + CertList->SignatureSize);
+ }
+ }
+
+ CertListSize -= CertList->SignatureListSize;
+ CertList = (EFI_SIGNATURE_LIST *) ((UINT8 *) CertList + CertList->SignatureListSize);
+ }
+
+ //
+ // Check X.509 Certificate Hash & Possible Timestamp.
+ //
+
+ //
+ // Retrieve the certificate stack from AuthData
+ // The output CertStack format will be:
+ // UINT8 CertNumber;
+ // UINT32 Cert1Length;
+ // UINT8 Cert1[];
+ // UINT32 Cert2Length;
+ // UINT8 Cert2[];
+ // ...
+ // UINT32 CertnLength;
+ // UINT8 Certn[];
+ //
+ Pkcs7GetSigners (AuthData, AuthDataSize, &CertBuffer, &BufferLength, &TrustedCert, &TrustedCertLength);
+ if ((BufferLength == 0) || (CertBuffer == NULL)) {
+ IsForbidden = TRUE;
+ goto Done;
+ }
+
+ //
+ // Check if any hash of certificates embedded in AuthData is in the forbidden database.
+ //
+ CertNumber = (UINT8) (*CertBuffer);
+ CertPtr = CertBuffer + 1;
+ for (Index = 0; Index < CertNumber; Index++) {
+ CertSize = (UINTN) ReadUnaligned32 ((UINT32 *)CertPtr);
+ Cert = (UINT8 *)CertPtr + sizeof (UINT32);
+ //
+ // Advance CertPtr to the next cert in image signer's cert list
+ //
+ CertPtr = CertPtr + sizeof (UINT32) + CertSize;
+
+ if (IsCertHashFoundInDatabase (Cert, CertSize, (EFI_SIGNATURE_LIST *)Data, DataSize, &RevocationTime)) {
+ //
+ // Check the timestamp signature and signing time to determine if the image can be trusted.
+ //
+ IsForbidden = TRUE;
+ if (PassTimestampCheck (AuthData, AuthDataSize, &RevocationTime)) {
+ IsForbidden = FALSE;
+ //
+ // Pass DBT check. Continue to check other certs in image signer's cert list against DBX, DBT
+ //
+ continue;
+ }
+ DEBUG ((DEBUG_INFO, "DxeImageVerificationLib: Image is signed but signature failed the timestamp check.\n"));
+ goto Done;
+ }
+
+ }
+
+Done:
+ if (Data != NULL) {
+ FreePool (Data);
+ }
+
+ Pkcs7FreeSigners (CertBuffer);
+ Pkcs7FreeSigners (TrustedCert);
+
+ return IsForbidden;
+}
+
+
+/**
+ Check whether the image signature can be verified by the trusted certificates in DB database.
+
+ @param[in] AuthData Pointer to the Authenticode signature retrieved from signed image.
+ @param[in] AuthDataSize Size of the Authenticode signature in bytes.
+
+ @retval TRUE Image passed verification using certificate in db.
+ @retval FALSE Image didn't pass verification using certificate in db.
+
+**/
+BOOLEAN
+IsAllowedByDb (
+ IN UINT8 *AuthData,
+ IN UINTN AuthDataSize
+ )
+{
+ EFI_STATUS Status;
+ BOOLEAN VerifyStatus;
+ EFI_SIGNATURE_LIST *CertList;
+ EFI_SIGNATURE_DATA *CertData;
UINTN DataSize;
UINT8 *Data;
UINT8 *RootCert;
UINTN RootCertSize;
UINTN Index;
UINTN CertCount;
-
- Data = NULL;
- CertList = NULL;
- Cert = NULL;
- RootCert = NULL;
- RootCertSize = 0;
- VerifyStatus = FALSE;
- PkcsCertData = (WIN_CERTIFICATE_EFI_PKCS *) (mImageBase + mSecDataDir->VirtualAddress);
+ UINTN DbxDataSize;
+ UINT8 *DbxData;
+ EFI_TIME RevocationTime;
+
+ Data = NULL;
+ CertList = NULL;
+ CertData = NULL;
+ RootCert = NULL;
+ DbxData = NULL;
+ RootCertSize = 0;
+ VerifyStatus = FALSE;
DataSize = 0;
- Status = gRT->GetVariable (VariableName, VendorGuid, NULL, &DataSize, NULL);
+ Status = gRT->GetVariable (EFI_IMAGE_SECURITY_DATABASE, &gEfiImageSecurityDatabaseGuid, NULL, &DataSize, NULL);
if (Status == EFI_BUFFER_TOO_SMALL) {
Data = (UINT8 *) AllocateZeroPool (DataSize);
if (Data == NULL) {
return VerifyStatus;
}
- Status = gRT->GetVariable (VariableName, VendorGuid, NULL, &DataSize, (VOID *) Data);
+ Status = gRT->GetVariable (EFI_IMAGE_SECURITY_DATABASE, &gEfiImageSecurityDatabaseGuid, NULL, &DataSize, (VOID *) Data);
if (EFI_ERROR (Status)) {
goto Done;
}
@@ -927,76 +1433,81 @@ IsPkcsSignedDataVerifiedBySignatureList (
CertList = (EFI_SIGNATURE_LIST *) Data;
while ((DataSize > 0) && (DataSize >= CertList->SignatureListSize)) {
if (CompareGuid (&CertList->SignatureType, &gEfiCertX509Guid)) {
- Cert = (EFI_SIGNATURE_DATA *) ((UINT8 *) CertList + sizeof (EFI_SIGNATURE_LIST) + CertList->SignatureHeaderSize);
- CertCount = (CertList->SignatureListSize - sizeof (EFI_SIGNATURE_LIST) - CertList->SignatureHeaderSize) / CertList->SignatureSize;
+ CertData = (EFI_SIGNATURE_DATA *) ((UINT8 *) CertList + sizeof (EFI_SIGNATURE_LIST) + CertList->SignatureHeaderSize);
+ CertCount = (CertList->SignatureListSize - sizeof (EFI_SIGNATURE_LIST) - CertList->SignatureHeaderSize) / CertList->SignatureSize;
+
for (Index = 0; Index < CertCount; Index++) {
//
// Iterate each Signature Data Node within this CertList for verify.
//
- RootCert = Cert->SignatureData;
- RootCertSize = CertList->SignatureSize - sizeof (EFI_GUID);
+ RootCert = CertData->SignatureData;
+ RootCertSize = CertList->SignatureSize - sizeof (EFI_GUID);
//
// Call AuthenticodeVerify library to Verify Authenticode struct.
//
VerifyStatus = AuthenticodeVerify (
- PkcsCertData->CertData,
- PkcsCertData->Hdr.dwLength - sizeof(PkcsCertData->Hdr),
+ AuthData,
+ AuthDataSize,
RootCert,
RootCertSize,
mImageDigest,
mImageDigestSize
);
if (VerifyStatus) {
+ //
+ // Here We still need to check if this RootCert's Hash is revoked
+ //
+ Status = gRT->GetVariable (EFI_IMAGE_SECURITY_DATABASE1, &gEfiImageSecurityDatabaseGuid, NULL, &DbxDataSize, NULL);
+ if (Status == EFI_BUFFER_TOO_SMALL) {
+ goto Done;
+ }
+ DbxData = (UINT8 *) AllocateZeroPool (DbxDataSize);
+ if (DbxData == NULL) {
+ goto Done;
+ }
+
+ Status = gRT->GetVariable (EFI_IMAGE_SECURITY_DATABASE1, &gEfiImageSecurityDatabaseGuid, NULL, &DbxDataSize, (VOID *) DbxData);
+ if (EFI_ERROR (Status)) {
+ goto Done;
+ }
+
+ if (IsCertHashFoundInDatabase (RootCert, RootCertSize, (EFI_SIGNATURE_LIST *)DbxData, DbxDataSize, &RevocationTime)) {
+ //
+ // Check the timestamp signature and signing time to determine if the RootCert can be trusted.
+ //
+ VerifyStatus = PassTimestampCheck (AuthData, AuthDataSize, &RevocationTime);
+ if (!VerifyStatus) {
+ DEBUG ((DEBUG_INFO, "DxeImageVerificationLib: Image is signed and signature is accepted by DB, but its root cert failed the timestamp check.\n"));
+ }
+ }
+
goto Done;
}
- Cert = (EFI_SIGNATURE_DATA *) ((UINT8 *) Cert + CertList->SignatureSize);
+
+ CertData = (EFI_SIGNATURE_DATA *) ((UINT8 *) CertData + CertList->SignatureSize);
}
}
+
DataSize -= CertList->SignatureListSize;
CertList = (EFI_SIGNATURE_LIST *) ((UINT8 *) CertList + CertList->SignatureListSize);
}
}
Done:
+
+ if (VerifyStatus) {
+ SecureBootHook (EFI_IMAGE_SECURITY_DATABASE, &gEfiImageSecurityDatabaseGuid, CertList->SignatureSize, CertData);
+ }
+
if (Data != NULL) {
FreePool (Data);
}
-
- return VerifyStatus;
-}
-
-/**
- Verify certificate in WIN_CERT_TYPE_PKCS_SIGNED_DATA format.
-
- @retval EFI_SUCCESS Image pass verification.
- @retval EFI_SECURITY_VIOLATION Image fail verification.
-
-**/
-EFI_STATUS
-VerifyCertPkcsSignedData (
- VOID
- )
-{
- //
- // 1: Find certificate from DBX forbidden database for revoked certificate.
- //
- if (IsPkcsSignedDataVerifiedBySignatureList (EFI_IMAGE_SECURITY_DATABASE1, &gEfiImageSecurityDatabaseGuid)) {
- //
- // DBX is forbidden database, if Authenticode verification pass with
- // one of the certificate in DBX, this image should be rejected.
- //
- return EFI_SECURITY_VIOLATION;
+ if (DbxData != NULL) {
+ FreePool (DbxData);
}
- //
- // 2: Find certificate from DB database and try to verify authenticode struct.
- //
- if (IsPkcsSignedDataVerifiedBySignatureList (EFI_IMAGE_SECURITY_DATABASE, &gEfiImageSecurityDatabaseGuid)) {
- return EFI_SUCCESS;
- } else {
- return EFI_SECURITY_VIOLATION;
- }
+ return VerifyStatus;
}
/**
@@ -1007,25 +1518,14 @@ VerifyCertPkcsSignedData (
In this implementation, only verify external executables when in USER MODE.
Executables from FV is bypass, so pass in AuthenticationStatus is ignored.
- The image verification process is:
+ The image verification policy is:
If the image is signed,
- If the image's certificate verifies against a certificate (root or intermediate) in the allowed
- database (DB) and not in the forbidden database (DBX), the certificate verification is passed.
- If the image's hash digest is in DBX,
- deny execution.
- If not,
- run it.
- If the Image's certificate verification failed.
- If the Image's Hash is in DB and not in DBX,
- run it.
- Otherwise,
- deny execution.
+ At least one valid signature or at least one hash value of the image must match a record
+ in the security database "db", and no valid signature nor any hash value of the image may
+ be reflected in the security database "dbx".
Otherwise, the image is not signed,
- Is the Image's Hash in DBX?
- If yes, deny execution.
- If not, is the Image's Hash in DB?
- If yes, run it.
- If not, deny execution.
+ The SHA256 hash value of the image must match a record in the security database "db", and
+ not be reflected in the security data base "dbx".
Caution: This function may receive untrusted input.
PE/COFF image is external input, so this function will validate its data structure
@@ -1068,7 +1568,6 @@ DxeImageVerificationHandler (
)
{
EFI_STATUS Status;
- UINT16 Magic;
EFI_IMAGE_DOS_HEADER *DosHdr;
EFI_STATUS VerifyStatus;
EFI_SIGNATURE_LIST *SignatureList;
@@ -1080,13 +1579,24 @@ DxeImageVerificationHandler (
UINT8 *SecureBoot;
PE_COFF_LOADER_IMAGE_CONTEXT ImageContext;
UINT32 NumberOfRvaAndSizes;
- UINT32 CertSize;
+ WIN_CERTIFICATE_EFI_PKCS *PkcsCertData;
+ WIN_CERTIFICATE_UEFI_GUID *WinCertUefiGuid;
+ UINT8 *AuthData;
+ UINTN AuthDataSize;
+ EFI_IMAGE_DATA_DIRECTORY *SecDataDir;
+ UINT32 OffSet;
+ CHAR16 *NameStr;
SignatureList = NULL;
SignatureListSize = 0;
WinCertificate = NULL;
+ SecDataDir = NULL;
+ PkcsCertData = NULL;
Action = EFI_IMAGE_EXECUTION_AUTH_UNTESTED;
Status = EFI_ACCESS_DENIED;
+ VerifyStatus = EFI_ACCESS_DENIED;
+
+
//
// Check the image type and get policy setting.
//
@@ -1121,6 +1631,15 @@ DxeImageVerificationHandler (
return EFI_ACCESS_DENIED;
}
+ //
+ // The policy QUERY_USER_ON_SECURITY_VIOLATION and ALLOW_EXECUTE_ON_SECURITY_VIOLATION
+ // violates the UEFI spec and has been removed.
+ //
+ ASSERT (Policy != QUERY_USER_ON_SECURITY_VIOLATION && Policy != ALLOW_EXECUTE_ON_SECURITY_VIOLATION);
+ if (Policy == QUERY_USER_ON_SECURITY_VIOLATION || Policy == ALLOW_EXECUTE_ON_SECURITY_VIOLATION) {
+ CpuDeadLoop ();
+ }
+
GetEfiGlobalVariable2 (EFI_SECURE_BOOT_MODE_NAME, (VOID**)&SecureBoot, NULL);
//
// Skip verification if SecureBoot variable doesn't exist.
@@ -1130,7 +1649,7 @@ DxeImageVerificationHandler (
}
//
- // Skip verification if SecureBoot is disabled.
+ // Skip verification if SecureBoot is disabled but not AuditMode
//
if (*SecureBoot == SECURE_BOOT_MODE_DISABLE) {
FreePool (SecureBoot);
@@ -1160,6 +1679,7 @@ DxeImageVerificationHandler (
//
// The information can't be got from the invalid PeImage
//
+ DEBUG ((DEBUG_INFO, "DxeImageVerificationLib: PeImage invalid. Cannot retrieve image information.\n"));
goto Done;
}
@@ -1183,47 +1703,38 @@ DxeImageVerificationHandler (
//
// It is not a valid Pe/Coff file.
//
+ DEBUG ((DEBUG_INFO, "DxeImageVerificationLib: Not a valid PE/COFF image.\n"));
goto Done;
}
- if (mNtHeader.Pe32->FileHeader.Machine == IMAGE_FILE_MACHINE_IA64 && mNtHeader.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
- //
- // NOTE: Some versions of Linux ELILO for Itanium have an incorrect magic value
- // in the PE/COFF Header. If the MachineType is Itanium(IA64) and the
- // Magic value in the OptionalHeader is EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC
- // then override the magic value to EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC
- //
- Magic = EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC;
- } else {
- //
- // Get the magic value from the PE/COFF Optional Header
- //
- Magic = mNtHeader.Pe32->OptionalHeader.Magic;
- }
-
- if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
+ if (mNtHeader.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
NumberOfRvaAndSizes = mNtHeader.Pe32->OptionalHeader.NumberOfRvaAndSizes;
if (NumberOfRvaAndSizes > EFI_IMAGE_DIRECTORY_ENTRY_SECURITY) {
- mSecDataDir = (EFI_IMAGE_DATA_DIRECTORY *) &mNtHeader.Pe32->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY];
- }
+ SecDataDir = (EFI_IMAGE_DATA_DIRECTORY *) &mNtHeader.Pe32->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY];
+ }
} else {
//
// Use PE32+ offset.
//
NumberOfRvaAndSizes = mNtHeader.Pe32Plus->OptionalHeader.NumberOfRvaAndSizes;
if (NumberOfRvaAndSizes > EFI_IMAGE_DIRECTORY_ENTRY_SECURITY) {
- mSecDataDir = (EFI_IMAGE_DATA_DIRECTORY *) &mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY];
+ SecDataDir = (EFI_IMAGE_DATA_DIRECTORY *) &mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY];
}
}
- if ((mSecDataDir == NULL) || ((mSecDataDir != NULL) && (mSecDataDir->Size == 0))) {
+ //
+ // Start Image Validation.
+ //
+ if (SecDataDir == NULL || SecDataDir->Size == 0) {
//
- // This image is not signed.
+ // This image is not signed. The SHA256 hash value of the image must match a record in the security database "db",
+ // and not be reflected in the security data base "dbx".
//
if (!HashPeImage (HASHALG_SHA256)) {
+ DEBUG ((DEBUG_INFO, "DxeImageVerificationLib: Failed to hash this image using %s.\n", mHashTypeStr));
goto Done;
}
@@ -1231,6 +1742,7 @@ DxeImageVerificationHandler (
//
// Image Hash is in forbidden database (DBX).
//
+ DEBUG ((DEBUG_INFO, "DxeImageVerificationLib: Image is not signed and %s hash of image is forbidden by DBX.\n", mHashTypeStr));
goto Done;
}
@@ -1244,85 +1756,126 @@ DxeImageVerificationHandler (
//
// Image Hash is not found in both forbidden and allowed database.
//
+ DEBUG ((DEBUG_INFO, "DxeImageVerificationLib: Image is not signed and %s hash of image is not found in DB/DBX.\n", mHashTypeStr));
goto Done;
}
//
- // Verify signature of executables.
+ // Verify the signature of the image, multiple signatures are allowed as per PE/COFF Section 4.7
+ // "Attribute Certificate Table".
+ // The first certificate starts at offset (SecDataDir->VirtualAddress) from the start of the file.
//
- WinCertificate = (WIN_CERTIFICATE *) (mImageBase + mSecDataDir->VirtualAddress);
-
- CertSize = sizeof (WIN_CERTIFICATE);
-
- if ((mSecDataDir->Size <= CertSize) || (mSecDataDir->Size < WinCertificate->dwLength)) {
- goto Done;
- }
-
- if (WinCertificate->wCertificateType == WIN_CERT_TYPE_PKCS_SIGNED_DATA) {
- //
- // Verify Pkcs signed data type.
- //
- Status = HashPeImageByType();
- if (EFI_ERROR (Status)) {
- goto Done;
+ for (OffSet = SecDataDir->VirtualAddress;
+ OffSet < (SecDataDir->VirtualAddress + SecDataDir->Size);
+ OffSet += (WinCertificate->dwLength + ALIGN_SIZE (WinCertificate->dwLength))) {
+ WinCertificate = (WIN_CERTIFICATE *) (mImageBase + OffSet);
+ if ((SecDataDir->VirtualAddress + SecDataDir->Size - OffSet) <= sizeof (WIN_CERTIFICATE) ||
+ (SecDataDir->VirtualAddress + SecDataDir->Size - OffSet) < WinCertificate->dwLength) {
+ break;
}
-
- VerifyStatus = VerifyCertPkcsSignedData ();
- } else {
- goto Done;
- }
- if (!EFI_ERROR (VerifyStatus)) {
//
- // Verification is passed.
- // Continue to check the image digest in signature database.
+ // Verify the image's Authenticode signature, only DER-encoded PKCS#7 signed data is supported.
//
- if (IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE1, mImageDigest, &mCertType, mImageDigestSize)) {
+ if (WinCertificate->wCertificateType == WIN_CERT_TYPE_PKCS_SIGNED_DATA) {
//
- // Executable signature verification passes, but is found in forbidden signature database.
+ // The certificate is formatted as WIN_CERTIFICATE_EFI_PKCS which is described in the
+ // Authenticode specification.
//
- Action = EFI_IMAGE_EXECUTION_AUTH_SIG_FOUND;
- Status = EFI_ACCESS_DENIED;
- } else {
+ PkcsCertData = (WIN_CERTIFICATE_EFI_PKCS *) WinCertificate;
+ if (PkcsCertData->Hdr.dwLength <= sizeof (PkcsCertData->Hdr)) {
+ break;
+ }
+ AuthData = PkcsCertData->CertData;
+ AuthDataSize = PkcsCertData->Hdr.dwLength - sizeof(PkcsCertData->Hdr);
+ } else if (WinCertificate->wCertificateType == WIN_CERT_TYPE_EFI_GUID) {
//
- // For image verification against enrolled X.509 certificate(root or intermediate),
- // no need to check image's hash in the allowed database.
+ // The certificate is formatted as WIN_CERTIFICATE_UEFI_GUID which is described in UEFI Spec.
//
- return EFI_SUCCESS;
+ WinCertUefiGuid = (WIN_CERTIFICATE_UEFI_GUID *) WinCertificate;
+ if (WinCertUefiGuid->Hdr.dwLength <= OFFSET_OF(WIN_CERTIFICATE_UEFI_GUID, CertData)) {
+ break;
+ }
+ if (!CompareGuid (&WinCertUefiGuid->CertType, &gEfiCertPkcs7Guid)) {
+ continue;
+ }
+ AuthData = WinCertUefiGuid->CertData;
+ AuthDataSize = WinCertUefiGuid->Hdr.dwLength - OFFSET_OF(WIN_CERTIFICATE_UEFI_GUID, CertData);
+ } else {
+ if (WinCertificate->dwLength < sizeof (WIN_CERTIFICATE)) {
+ break;
+ }
+ continue;
}
- } else {
+
+ Status = HashPeImageByType (AuthData, AuthDataSize);
+ if (EFI_ERROR (Status)) {
+ continue;
+ }
+
//
- // Verification failure.
+ // Check the digital signature against the revoked certificate in forbidden database (dbx).
//
- if (!IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE1, mImageDigest, &mCertType, mImageDigestSize) &&
- IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE, mImageDigest, &mCertType, mImageDigestSize)) {
- //
- // Verification fail, Image Hash is not in forbidden database (DBX),
- // and Image Hash is in allowed database (DB).
- //
- Status = EFI_SUCCESS;
- } else {
+ if (IsForbiddenByDbx (AuthData, AuthDataSize)) {
Action = EFI_IMAGE_EXECUTION_AUTH_SIG_FAILED;
- Status = EFI_ACCESS_DENIED;
+ VerifyStatus = EFI_ACCESS_DENIED;
+ break;
+ }
+
+ //
+ // Check the digital signature against the valid certificate in allowed database (db).
+ //
+ if (EFI_ERROR (VerifyStatus)) {
+ if (IsAllowedByDb (AuthData, AuthDataSize)) {
+ VerifyStatus = EFI_SUCCESS;
+ }
+ }
+
+ //
+ // Check the image's hash value.
+ //
+ if (IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE1, mImageDigest, &mCertType, mImageDigestSize)) {
+ Action = EFI_IMAGE_EXECUTION_AUTH_SIG_FOUND;
+ DEBUG ((DEBUG_INFO, "DxeImageVerificationLib: Image is signed but %s hash of image is found in DBX.\n", mHashTypeStr));
+ VerifyStatus = EFI_ACCESS_DENIED;
+ break;
+ } else if (EFI_ERROR (VerifyStatus)) {
+ if (IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE, mImageDigest, &mCertType, mImageDigestSize)) {
+ VerifyStatus = EFI_SUCCESS;
+ } else {
+ 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));
+ }
}
}
- if (EFI_ERROR (Status)) {
+ if (OffSet != (SecDataDir->VirtualAddress + SecDataDir->Size)) {
//
- // Get image hash value as executable's signature.
+ // The Size in Certificate Table or the attribute certicate table is corrupted.
//
- SignatureListSize = sizeof (EFI_SIGNATURE_LIST) + sizeof (EFI_SIGNATURE_DATA) - 1 + mImageDigestSize;
- SignatureList = (EFI_SIGNATURE_LIST *) AllocateZeroPool (SignatureListSize);
- if (SignatureList == NULL) {
- Status = EFI_OUT_OF_RESOURCES;
- goto Done;
+ VerifyStatus = EFI_ACCESS_DENIED;
+ }
+
+ if (!EFI_ERROR (VerifyStatus)) {
+ return EFI_SUCCESS;
+ } else {
+ Status = EFI_ACCESS_DENIED;
+ if (Action == EFI_IMAGE_EXECUTION_AUTH_SIG_FAILED || Action == EFI_IMAGE_EXECUTION_AUTH_SIG_FOUND) {
+ //
+ // Get image hash value as executable's signature.
+ //
+ SignatureListSize = sizeof (EFI_SIGNATURE_LIST) + sizeof (EFI_SIGNATURE_DATA) - 1 + mImageDigestSize;
+ SignatureList = (EFI_SIGNATURE_LIST *) AllocateZeroPool (SignatureListSize);
+ if (SignatureList == NULL) {
+ Status = EFI_OUT_OF_RESOURCES;
+ goto Done;
+ }
+ SignatureList->SignatureHeaderSize = 0;
+ SignatureList->SignatureListSize = (UINT32) SignatureListSize;
+ SignatureList->SignatureSize = (UINT32) (sizeof (EFI_SIGNATURE_DATA) - 1 + mImageDigestSize);
+ CopyMem (&SignatureList->SignatureType, &mCertType, sizeof (EFI_GUID));
+ Signature = (EFI_SIGNATURE_DATA *) ((UINT8 *) SignatureList + sizeof (EFI_SIGNATURE_LIST));
+ CopyMem (Signature->SignatureData, mImageDigest, mImageDigestSize);
}
- SignatureList->SignatureHeaderSize = 0;
- SignatureList->SignatureListSize = (UINT32) SignatureListSize;
- SignatureList->SignatureSize = (UINT32) mImageDigestSize;
- CopyMem (&SignatureList->SignatureType, &mCertType, sizeof (EFI_GUID));
- Signature = (EFI_SIGNATURE_DATA *) ((UINT8 *) SignatureList + sizeof (EFI_SIGNATURE_LIST));
- CopyMem (Signature->SignatureData, mImageDigest, mImageDigestSize);
}
Done:
@@ -1330,7 +1883,12 @@ Done:
//
// Policy decides to defer or reject the image; add its information in image executable information table.
//
- AddImageExeInfo (Action, NULL, File, SignatureList, SignatureListSize);
+ NameStr = ConvertDevicePathToText (File, FALSE, TRUE);
+ AddImageExeInfo (Action, NameStr, File, SignatureList, SignatureListSize);
+ if (NameStr != NULL) {
+ DEBUG((EFI_D_INFO, "The image doesn't pass verification: %s\n", NameStr));
+ FreePool(NameStr);
+ }
Status = EFI_SECURITY_VIOLATION;
}
@@ -1342,50 +1900,38 @@ Done:
}
/**
- When VariableWriteArchProtocol install, create "SecureBoot" variable.
+ On Ready To Boot Services Event notification handler.
- @param[in] Event Event whose notification function is being invoked.
- @param[in] Context Pointer to the notification function's context.
+ Add the image execution information table if it is not in system configuration table.
+
+ @param[in] Event Event whose notification function is being invoked
+ @param[in] Context Pointer to the notification function's context
**/
VOID
EFIAPI
-VariableWriteCallBack (
- IN EFI_EVENT Event,
- IN VOID *Context
+OnReadyToBoot (
+ IN EFI_EVENT Event,
+ IN VOID *Context
)
{
- UINT8 SecureBootMode;
- UINT8 *SecureBootModePtr;
- EFI_STATUS Status;
- VOID *ProtocolPointer;
+ EFI_IMAGE_EXECUTION_INFO_TABLE *ImageExeInfoTable;
+ UINTN ImageExeInfoTableSize;
- Status = gBS->LocateProtocol (&gEfiVariableWriteArchProtocolGuid, NULL, &ProtocolPointer);
- if (EFI_ERROR (Status)) {
+ EfiGetSystemConfigurationTable (&gEfiImageSecurityDatabaseGuid, (VOID **) &ImageExeInfoTable);
+ if (ImageExeInfoTable != NULL) {
return;
}
- //
- // Check whether "SecureBoot" variable exists.
- // If this library is built-in, it means firmware has capability to perform
- // driver signing verification.
- //
- GetEfiGlobalVariable2 (EFI_SECURE_BOOT_MODE_NAME, (VOID**)&SecureBootModePtr, NULL);
- if (SecureBootModePtr == NULL) {
- SecureBootMode = SECURE_BOOT_MODE_DISABLE;
- //
- // Authenticated variable driver will update "SecureBoot" depending on SetupMode variable.
- //
- gRT->SetVariable (
- EFI_SECURE_BOOT_MODE_NAME,
- &gEfiGlobalVariableGuid,
- EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_NON_VOLATILE,
- sizeof (UINT8),
- &SecureBootMode
- );
- } else {
- FreePool (SecureBootModePtr);
+ ImageExeInfoTableSize = sizeof (EFI_IMAGE_EXECUTION_INFO_TABLE);
+ ImageExeInfoTable = (EFI_IMAGE_EXECUTION_INFO_TABLE *) AllocateRuntimePool (ImageExeInfoTableSize);
+ if (ImageExeInfoTable == NULL) {
+ return ;
}
+
+ ImageExeInfoTable->NumberOfImages = 0;
+ gBS->InstallConfigurationTable (&gEfiImageSecurityDatabaseGuid, (VOID *) ImageExeInfoTable);
+
}
/**
@@ -1403,17 +1949,16 @@ DxeImageVerificationLibConstructor (
IN EFI_SYSTEM_TABLE *SystemTable
)
{
- VOID *Registration;
+ EFI_EVENT Event;
//
- // Register callback function upon VariableWriteArchProtocol.
+ // Register the event to publish the image execution table.
//
- EfiCreateProtocolNotifyEvent (
- &gEfiVariableWriteArchProtocolGuid,
+ EfiCreateEventReadyToBootEx (
TPL_CALLBACK,
- VariableWriteCallBack,
+ OnReadyToBoot,
NULL,
- &Registration
+ &Event
);
return RegisterSecurity2Handler (