mirror of https://github.com/acidanthera/audk.git
1400 lines
48 KiB
C
1400 lines
48 KiB
C
/** @file
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Implement image verification services for secure boot service in UEFI2.3.1.
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Caution: This file requires additional review when modified.
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This library will have external input - PE/COFF image.
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This external input must be validated carefully to avoid security issue like
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buffer overflow, integer overflow.
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DxeImageVerificationLibImageRead() function will make sure the PE/COFF image content
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read is within the image buffer.
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DxeImageVerificationHandler(), HashPeImageByType(), HashPeImage() function will accept
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untrusted PE/COFF image and validate its data structure within this image buffer before use.
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Copyright (c) 2009 - 2013, Intel Corporation. All rights reserved.<BR>
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This program and the accompanying materials
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are licensed and made available under the terms and conditions of the BSD License
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which accompanies this distribution. The full text of the license may be found at
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http://opensource.org/licenses/bsd-license.php
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THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
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WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
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**/
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#include "DxeImageVerificationLib.h"
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//
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// Caution: This is used by a function which may receive untrusted input.
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// These global variables hold PE/COFF image data, and they should be validated before use.
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//
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EFI_IMAGE_OPTIONAL_HEADER_PTR_UNION mNtHeader;
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UINT32 mPeCoffHeaderOffset;
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EFI_GUID mCertType;
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//
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// Information on current PE/COFF image
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//
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UINTN mImageSize;
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UINT8 *mImageBase = NULL;
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UINT8 mImageDigest[MAX_DIGEST_SIZE];
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UINTN mImageDigestSize;
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//
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// Notify string for authorization UI.
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//
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CHAR16 mNotifyString1[MAX_NOTIFY_STRING_LEN] = L"Image verification pass but not found in authorized database!";
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CHAR16 mNotifyString2[MAX_NOTIFY_STRING_LEN] = L"Launch this image anyway? (Yes/Defer/No)";
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//
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// Public Exponent of RSA Key.
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//
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CONST UINT8 mRsaE[] = { 0x01, 0x00, 0x01 };
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//
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// OID ASN.1 Value for Hash Algorithms
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//
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UINT8 mHashOidValue[] = {
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0x2B, 0x0E, 0x03, 0x02, 0x1A, // OBJ_sha1
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0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04, // OBJ_sha224
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0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, // OBJ_sha256
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0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02, // OBJ_sha384
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0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, // OBJ_sha512
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};
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HASH_TABLE mHash[] = {
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{ L"SHA1", 20, &mHashOidValue[0], 5, Sha1GetContextSize, Sha1Init, Sha1Update, Sha1Final },
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{ L"SHA224", 28, &mHashOidValue[5], 9, NULL, NULL, NULL, NULL },
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{ L"SHA256", 32, &mHashOidValue[14], 9, Sha256GetContextSize,Sha256Init, Sha256Update, Sha256Final},
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{ L"SHA384", 48, &mHashOidValue[23], 9, NULL, NULL, NULL, NULL },
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{ L"SHA512", 64, &mHashOidValue[32], 9, NULL, NULL, NULL, NULL }
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};
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/**
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SecureBoot Hook for processing image verification.
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@param[in] VariableName Name of Variable to be found.
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@param[in] VendorGuid Variable vendor GUID.
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@param[in] DataSize Size of Data found. If size is less than the
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data, this value contains the required size.
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@param[in] Data Data pointer.
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**/
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VOID
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EFIAPI
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SecureBootHook (
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IN CHAR16 *VariableName,
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IN EFI_GUID *VendorGuid,
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IN UINTN DataSize,
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IN VOID *Data
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);
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/**
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Reads contents of a PE/COFF image in memory buffer.
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Caution: This function may receive untrusted input.
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PE/COFF image is external input, so this function will make sure the PE/COFF image content
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read is within the image buffer.
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@param FileHandle Pointer to the file handle to read the PE/COFF image.
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@param FileOffset Offset into the PE/COFF image to begin the read operation.
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@param ReadSize On input, the size in bytes of the requested read operation.
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On output, the number of bytes actually read.
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@param Buffer Output buffer that contains the data read from the PE/COFF image.
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@retval EFI_SUCCESS The specified portion of the PE/COFF image was read and the size
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**/
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EFI_STATUS
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EFIAPI
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DxeImageVerificationLibImageRead (
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IN VOID *FileHandle,
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IN UINTN FileOffset,
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IN OUT UINTN *ReadSize,
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OUT VOID *Buffer
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)
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{
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UINTN EndPosition;
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if (FileHandle == NULL || ReadSize == NULL || Buffer == NULL) {
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return EFI_INVALID_PARAMETER;
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}
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if (MAX_ADDRESS - FileOffset < *ReadSize) {
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return EFI_INVALID_PARAMETER;
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}
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EndPosition = FileOffset + *ReadSize;
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if (EndPosition > mImageSize) {
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*ReadSize = (UINT32)(mImageSize - FileOffset);
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}
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if (FileOffset >= mImageSize) {
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*ReadSize = 0;
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}
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CopyMem (Buffer, (UINT8 *)((UINTN) FileHandle + FileOffset), *ReadSize);
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return EFI_SUCCESS;
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}
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/**
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Get the image type.
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@param[in] File This is a pointer to the device path of the file that is
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being dispatched.
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@return UINT32 Image Type
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**/
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UINT32
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GetImageType (
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IN CONST EFI_DEVICE_PATH_PROTOCOL *File
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)
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{
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EFI_STATUS Status;
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EFI_HANDLE DeviceHandle;
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EFI_DEVICE_PATH_PROTOCOL *TempDevicePath;
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EFI_BLOCK_IO_PROTOCOL *BlockIo;
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if (File == NULL) {
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return IMAGE_UNKNOWN;
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}
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//
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// First check to see if File is from a Firmware Volume
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//
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DeviceHandle = NULL;
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TempDevicePath = (EFI_DEVICE_PATH_PROTOCOL *) File;
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Status = gBS->LocateDevicePath (
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&gEfiFirmwareVolume2ProtocolGuid,
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&TempDevicePath,
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&DeviceHandle
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);
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if (!EFI_ERROR (Status)) {
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Status = gBS->OpenProtocol (
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DeviceHandle,
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&gEfiFirmwareVolume2ProtocolGuid,
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NULL,
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NULL,
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NULL,
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EFI_OPEN_PROTOCOL_TEST_PROTOCOL
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);
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if (!EFI_ERROR (Status)) {
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return IMAGE_FROM_FV;
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}
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}
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//
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// Next check to see if File is from a Block I/O device
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//
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DeviceHandle = NULL;
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TempDevicePath = (EFI_DEVICE_PATH_PROTOCOL *) File;
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Status = gBS->LocateDevicePath (
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&gEfiBlockIoProtocolGuid,
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&TempDevicePath,
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&DeviceHandle
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);
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if (!EFI_ERROR (Status)) {
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BlockIo = NULL;
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Status = gBS->OpenProtocol (
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DeviceHandle,
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&gEfiBlockIoProtocolGuid,
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(VOID **) &BlockIo,
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NULL,
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NULL,
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EFI_OPEN_PROTOCOL_GET_PROTOCOL
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);
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if (!EFI_ERROR (Status) && BlockIo != NULL) {
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if (BlockIo->Media != NULL) {
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if (BlockIo->Media->RemovableMedia) {
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//
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// Block I/O is present and specifies the media is removable
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//
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return IMAGE_FROM_REMOVABLE_MEDIA;
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} else {
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//
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// Block I/O is present and specifies the media is not removable
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//
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return IMAGE_FROM_FIXED_MEDIA;
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}
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}
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}
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}
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//
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// File is not in a Firmware Volume or on a Block I/O device, so check to see if
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// the device path supports the Simple File System Protocol.
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//
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DeviceHandle = NULL;
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TempDevicePath = (EFI_DEVICE_PATH_PROTOCOL *) File;
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Status = gBS->LocateDevicePath (
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&gEfiSimpleFileSystemProtocolGuid,
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&TempDevicePath,
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&DeviceHandle
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);
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if (!EFI_ERROR (Status)) {
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//
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// Simple File System is present without Block I/O, so assume media is fixed.
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//
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return IMAGE_FROM_FIXED_MEDIA;
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}
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//
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// File is not from an FV, Block I/O or Simple File System, so the only options
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// left are a PCI Option ROM and a Load File Protocol such as a PXE Boot from a NIC.
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//
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TempDevicePath = (EFI_DEVICE_PATH_PROTOCOL *) File;
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while (!IsDevicePathEndType (TempDevicePath)) {
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switch (DevicePathType (TempDevicePath)) {
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case MEDIA_DEVICE_PATH:
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if (DevicePathSubType (TempDevicePath) == MEDIA_RELATIVE_OFFSET_RANGE_DP) {
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return IMAGE_FROM_OPTION_ROM;
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}
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break;
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case MESSAGING_DEVICE_PATH:
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if (DevicePathSubType(TempDevicePath) == MSG_MAC_ADDR_DP) {
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return IMAGE_FROM_REMOVABLE_MEDIA;
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}
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break;
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default:
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break;
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}
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TempDevicePath = NextDevicePathNode (TempDevicePath);
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}
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return IMAGE_UNKNOWN;
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}
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/**
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Caculate hash of Pe/Coff image based on the authenticode image hashing in
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PE/COFF Specification 8.0 Appendix A
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Caution: This function may receive untrusted input.
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PE/COFF image is external input, so this function will validate its data structure
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within this image buffer before use.
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@param[in] HashAlg Hash algorithm type.
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@retval TRUE Successfully hash image.
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@retval FALSE Fail in hash image.
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**/
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BOOLEAN
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HashPeImage (
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IN UINT32 HashAlg
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)
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{
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BOOLEAN Status;
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UINT16 Magic;
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EFI_IMAGE_SECTION_HEADER *Section;
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VOID *HashCtx;
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UINTN CtxSize;
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UINT8 *HashBase;
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UINTN HashSize;
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UINTN SumOfBytesHashed;
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EFI_IMAGE_SECTION_HEADER *SectionHeader;
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UINTN Index;
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UINTN Pos;
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UINT32 CertSize;
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UINT32 NumberOfRvaAndSizes;
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HashCtx = NULL;
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SectionHeader = NULL;
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Status = FALSE;
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if ((HashAlg != HASHALG_SHA1) && (HashAlg != HASHALG_SHA256)) {
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return FALSE;
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}
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//
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// Initialize context of hash.
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//
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ZeroMem (mImageDigest, MAX_DIGEST_SIZE);
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if (HashAlg == HASHALG_SHA1) {
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mImageDigestSize = SHA1_DIGEST_SIZE;
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mCertType = gEfiCertSha1Guid;
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} else if (HashAlg == HASHALG_SHA256) {
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mImageDigestSize = SHA256_DIGEST_SIZE;
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mCertType = gEfiCertSha256Guid;
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} else {
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return FALSE;
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}
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CtxSize = mHash[HashAlg].GetContextSize();
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HashCtx = AllocatePool (CtxSize);
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if (HashCtx == NULL) {
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return FALSE;
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}
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// 1. Load the image header into memory.
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// 2. Initialize a SHA hash context.
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Status = mHash[HashAlg].HashInit(HashCtx);
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if (!Status) {
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goto Done;
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}
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//
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// Measuring PE/COFF Image Header;
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// But CheckSum field and SECURITY data directory (certificate) are excluded
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//
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if (mNtHeader.Pe32->FileHeader.Machine == IMAGE_FILE_MACHINE_IA64 && mNtHeader.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
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//
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// NOTE: Some versions of Linux ELILO for Itanium have an incorrect magic value
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// in the PE/COFF Header. If the MachineType is Itanium(IA64) and the
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// Magic value in the OptionalHeader is EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC
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// then override the magic value to EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC
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//
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Magic = EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC;
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} else {
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//
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// Get the magic value from the PE/COFF Optional Header
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//
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Magic = mNtHeader.Pe32->OptionalHeader.Magic;
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}
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//
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// 3. Calculate the distance from the base of the image header to the image checksum address.
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// 4. Hash the image header from its base to beginning of the image checksum.
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//
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HashBase = mImageBase;
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if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
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//
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// Use PE32 offset.
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//
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HashSize = (UINTN) ((UINT8 *) (&mNtHeader.Pe32->OptionalHeader.CheckSum) - HashBase);
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NumberOfRvaAndSizes = mNtHeader.Pe32->OptionalHeader.NumberOfRvaAndSizes;
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} else if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC) {
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//
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// Use PE32+ offset.
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//
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HashSize = (UINTN) ((UINT8 *) (&mNtHeader.Pe32Plus->OptionalHeader.CheckSum) - HashBase);
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NumberOfRvaAndSizes = mNtHeader.Pe32Plus->OptionalHeader.NumberOfRvaAndSizes;
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} else {
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//
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// Invalid header magic number.
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//
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Status = FALSE;
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goto Done;
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}
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Status = mHash[HashAlg].HashUpdate(HashCtx, HashBase, HashSize);
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if (!Status) {
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goto Done;
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}
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//
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// 5. Skip over the image checksum (it occupies a single ULONG).
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//
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if (NumberOfRvaAndSizes <= EFI_IMAGE_DIRECTORY_ENTRY_SECURITY) {
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//
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// 6. Since there is no Cert Directory in optional header, hash everything
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// from the end of the checksum to the end of image header.
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//
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if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
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//
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// Use PE32 offset.
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//
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HashBase = (UINT8 *) &mNtHeader.Pe32->OptionalHeader.CheckSum + sizeof (UINT32);
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HashSize = mNtHeader.Pe32->OptionalHeader.SizeOfHeaders - (UINTN) (HashBase - mImageBase);
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} else {
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//
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// Use PE32+ offset.
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//
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HashBase = (UINT8 *) &mNtHeader.Pe32Plus->OptionalHeader.CheckSum + sizeof (UINT32);
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HashSize = mNtHeader.Pe32Plus->OptionalHeader.SizeOfHeaders - (UINTN) (HashBase - mImageBase);
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}
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|
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if (HashSize != 0) {
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Status = mHash[HashAlg].HashUpdate(HashCtx, HashBase, HashSize);
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if (!Status) {
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goto Done;
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}
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}
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} else {
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//
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// 7. Hash everything from the end of the checksum to the start of the Cert Directory.
|
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//
|
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if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
|
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//
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// Use PE32 offset.
|
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//
|
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HashBase = (UINT8 *) &mNtHeader.Pe32->OptionalHeader.CheckSum + sizeof (UINT32);
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HashSize = (UINTN) ((UINT8 *) (&mNtHeader.Pe32->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY]) - HashBase);
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} else {
|
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//
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// Use PE32+ offset.
|
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//
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HashBase = (UINT8 *) &mNtHeader.Pe32Plus->OptionalHeader.CheckSum + sizeof (UINT32);
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HashSize = (UINTN) ((UINT8 *) (&mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY]) - HashBase);
|
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}
|
|
|
|
if (HashSize != 0) {
|
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Status = mHash[HashAlg].HashUpdate(HashCtx, HashBase, HashSize);
|
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if (!Status) {
|
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goto Done;
|
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}
|
|
}
|
|
|
|
//
|
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// 8. Skip over the Cert Directory. (It is sizeof(IMAGE_DATA_DIRECTORY) bytes.)
|
|
// 9. Hash everything from the end of the Cert Directory to the end of image header.
|
|
//
|
|
if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
|
|
//
|
|
// Use PE32 offset
|
|
//
|
|
HashBase = (UINT8 *) &mNtHeader.Pe32->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY + 1];
|
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HashSize = mNtHeader.Pe32->OptionalHeader.SizeOfHeaders - (UINTN) (HashBase - mImageBase);
|
|
} else {
|
|
//
|
|
// Use PE32+ offset.
|
|
//
|
|
HashBase = (UINT8 *) &mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY + 1];
|
|
HashSize = mNtHeader.Pe32Plus->OptionalHeader.SizeOfHeaders - (UINTN) (HashBase - mImageBase);
|
|
}
|
|
|
|
if (HashSize != 0) {
|
|
Status = mHash[HashAlg].HashUpdate(HashCtx, HashBase, HashSize);
|
|
if (!Status) {
|
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goto Done;
|
|
}
|
|
}
|
|
}
|
|
|
|
//
|
|
// 10. Set the SUM_OF_BYTES_HASHED to the size of the header.
|
|
//
|
|
if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
|
|
//
|
|
// Use PE32 offset.
|
|
//
|
|
SumOfBytesHashed = mNtHeader.Pe32->OptionalHeader.SizeOfHeaders;
|
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} else {
|
|
//
|
|
// Use PE32+ offset
|
|
//
|
|
SumOfBytesHashed = mNtHeader.Pe32Plus->OptionalHeader.SizeOfHeaders;
|
|
}
|
|
|
|
|
|
Section = (EFI_IMAGE_SECTION_HEADER *) (
|
|
mImageBase +
|
|
mPeCoffHeaderOffset +
|
|
sizeof (UINT32) +
|
|
sizeof (EFI_IMAGE_FILE_HEADER) +
|
|
mNtHeader.Pe32->FileHeader.SizeOfOptionalHeader
|
|
);
|
|
|
|
//
|
|
// 11. Build a temporary table of pointers to all the IMAGE_SECTION_HEADER
|
|
// structures in the image. The 'NumberOfSections' field of the image
|
|
// header indicates how big the table should be. Do not include any
|
|
// IMAGE_SECTION_HEADERs in the table whose 'SizeOfRawData' field is zero.
|
|
//
|
|
SectionHeader = (EFI_IMAGE_SECTION_HEADER *) AllocateZeroPool (sizeof (EFI_IMAGE_SECTION_HEADER) * mNtHeader.Pe32->FileHeader.NumberOfSections);
|
|
if (SectionHeader == NULL) {
|
|
Status = FALSE;
|
|
goto Done;
|
|
}
|
|
//
|
|
// 12. Using the 'PointerToRawData' in the referenced section headers as
|
|
// a key, arrange the elements in the table in ascending order. In other
|
|
// words, sort the section headers according to the disk-file offset of
|
|
// the section.
|
|
//
|
|
for (Index = 0; Index < mNtHeader.Pe32->FileHeader.NumberOfSections; Index++) {
|
|
Pos = Index;
|
|
while ((Pos > 0) && (Section->PointerToRawData < SectionHeader[Pos - 1].PointerToRawData)) {
|
|
CopyMem (&SectionHeader[Pos], &SectionHeader[Pos - 1], sizeof (EFI_IMAGE_SECTION_HEADER));
|
|
Pos--;
|
|
}
|
|
CopyMem (&SectionHeader[Pos], Section, sizeof (EFI_IMAGE_SECTION_HEADER));
|
|
Section += 1;
|
|
}
|
|
|
|
//
|
|
// 13. Walk through the sorted table, bring the corresponding section
|
|
// into memory, and hash the entire section (using the 'SizeOfRawData'
|
|
// field in the section header to determine the amount of data to hash).
|
|
// 14. Add the section's 'SizeOfRawData' to SUM_OF_BYTES_HASHED .
|
|
// 15. Repeat steps 13 and 14 for all the sections in the sorted table.
|
|
//
|
|
for (Index = 0; Index < mNtHeader.Pe32->FileHeader.NumberOfSections; Index++) {
|
|
Section = &SectionHeader[Index];
|
|
if (Section->SizeOfRawData == 0) {
|
|
continue;
|
|
}
|
|
HashBase = mImageBase + Section->PointerToRawData;
|
|
HashSize = (UINTN) Section->SizeOfRawData;
|
|
|
|
Status = mHash[HashAlg].HashUpdate(HashCtx, HashBase, HashSize);
|
|
if (!Status) {
|
|
goto Done;
|
|
}
|
|
|
|
SumOfBytesHashed += HashSize;
|
|
}
|
|
|
|
//
|
|
// 16. If the file size is greater than SUM_OF_BYTES_HASHED, there is extra
|
|
// data in the file that needs to be added to the hash. This data begins
|
|
// at file offset SUM_OF_BYTES_HASHED and its length is:
|
|
// FileSize - (CertDirectory->Size)
|
|
//
|
|
if (mImageSize > SumOfBytesHashed) {
|
|
HashBase = mImageBase + SumOfBytesHashed;
|
|
|
|
if (NumberOfRvaAndSizes <= EFI_IMAGE_DIRECTORY_ENTRY_SECURITY) {
|
|
CertSize = 0;
|
|
} else {
|
|
if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
|
|
//
|
|
// Use PE32 offset.
|
|
//
|
|
CertSize = mNtHeader.Pe32->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY].Size;
|
|
} else {
|
|
//
|
|
// Use PE32+ offset.
|
|
//
|
|
CertSize = mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY].Size;
|
|
}
|
|
}
|
|
|
|
if (mImageSize > CertSize + SumOfBytesHashed) {
|
|
HashSize = (UINTN) (mImageSize - CertSize - SumOfBytesHashed);
|
|
|
|
Status = mHash[HashAlg].HashUpdate(HashCtx, HashBase, HashSize);
|
|
if (!Status) {
|
|
goto Done;
|
|
}
|
|
} else if (mImageSize < CertSize + SumOfBytesHashed) {
|
|
Status = FALSE;
|
|
goto Done;
|
|
}
|
|
}
|
|
|
|
Status = mHash[HashAlg].HashFinal(HashCtx, mImageDigest);
|
|
|
|
Done:
|
|
if (HashCtx != NULL) {
|
|
FreePool (HashCtx);
|
|
}
|
|
if (SectionHeader != NULL) {
|
|
FreePool (SectionHeader);
|
|
}
|
|
return Status;
|
|
}
|
|
|
|
/**
|
|
Recognize the Hash algorithm in PE/COFF Authenticode and caculate hash of
|
|
Pe/Coff image based on the authenticode image hashing in PE/COFF Specification
|
|
8.0 Appendix A
|
|
|
|
Caution: This function may receive untrusted input.
|
|
PE/COFF image is external input, so this function will validate its data structure
|
|
within this image buffer before use.
|
|
|
|
@param[in] 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 (
|
|
IN UINT8 *AuthData,
|
|
IN UINTN AuthDataSize
|
|
)
|
|
{
|
|
UINT8 Index;
|
|
|
|
for (Index = 0; Index < HASHALG_MAX; Index++) {
|
|
//
|
|
// Check the Hash algorithm in PE/COFF Authenticode.
|
|
// According to PKCS#7 Definition:
|
|
// SignedData ::= SEQUENCE {
|
|
// version Version,
|
|
// digestAlgorithms DigestAlgorithmIdentifiers,
|
|
// contentInfo ContentInfo,
|
|
// .... }
|
|
// The DigestAlgorithmIdentifiers can be used to determine the hash algorithm in PE/COFF hashing
|
|
// This field has the fixed offset (+32) in final Authenticode ASN.1 data.
|
|
// Fixed offset (+32) is calculated based on two bytes of length encoding.
|
|
//
|
|
if ((*(AuthData + 1) & TWO_BYTE_ENCODE) != TWO_BYTE_ENCODE) {
|
|
//
|
|
// Only support two bytes of Long Form of Length Encoding.
|
|
//
|
|
continue;
|
|
}
|
|
|
|
if (AuthDataSize < 32 + mHash[Index].OidLength) {
|
|
return EFI_UNSUPPORTED;
|
|
}
|
|
|
|
if (CompareMem (AuthData + 32, mHash[Index].OidValue, mHash[Index].OidLength) == 0) {
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (Index == HASHALG_MAX) {
|
|
return EFI_UNSUPPORTED;
|
|
}
|
|
|
|
//
|
|
// HASH PE Image based on Hash algorithm in PE/COFF Authenticode.
|
|
//
|
|
if (!HashPeImage(Index)) {
|
|
return EFI_UNSUPPORTED;
|
|
}
|
|
|
|
return EFI_SUCCESS;
|
|
}
|
|
|
|
|
|
/**
|
|
Returns the size of a given image execution info table in bytes.
|
|
|
|
This function returns the size, in bytes, of the image execution info table specified by
|
|
ImageExeInfoTable. If ImageExeInfoTable is NULL, then 0 is returned.
|
|
|
|
@param ImageExeInfoTable A pointer to a image execution info table structure.
|
|
|
|
@retval 0 If ImageExeInfoTable is NULL.
|
|
@retval Others The size of a image execution info table in bytes.
|
|
|
|
**/
|
|
UINTN
|
|
GetImageExeInfoTableSize (
|
|
EFI_IMAGE_EXECUTION_INFO_TABLE *ImageExeInfoTable
|
|
)
|
|
{
|
|
UINTN Index;
|
|
EFI_IMAGE_EXECUTION_INFO *ImageExeInfoItem;
|
|
UINTN TotalSize;
|
|
|
|
if (ImageExeInfoTable == NULL) {
|
|
return 0;
|
|
}
|
|
|
|
ImageExeInfoItem = (EFI_IMAGE_EXECUTION_INFO *) ((UINT8 *) ImageExeInfoTable + sizeof (EFI_IMAGE_EXECUTION_INFO_TABLE));
|
|
TotalSize = sizeof (EFI_IMAGE_EXECUTION_INFO_TABLE);
|
|
for (Index = 0; Index < ImageExeInfoTable->NumberOfImages; Index++) {
|
|
TotalSize += ReadUnaligned32 ((UINT32 *) &ImageExeInfoItem->InfoSize);
|
|
ImageExeInfoItem = (EFI_IMAGE_EXECUTION_INFO *) ((UINT8 *) ImageExeInfoItem + ReadUnaligned32 ((UINT32 *) &ImageExeInfoItem->InfoSize));
|
|
}
|
|
|
|
return TotalSize;
|
|
}
|
|
|
|
/**
|
|
Create an Image Execution Information Table entry and add it to system configuration table.
|
|
|
|
@param[in] Action Describes the action taken by the firmware regarding this image.
|
|
@param[in] Name Input a null-terminated, user-friendly name.
|
|
@param[in] DevicePath Input device path pointer.
|
|
@param[in] Signature Input signature info in EFI_SIGNATURE_LIST data structure.
|
|
@param[in] SignatureSize Size of signature.
|
|
|
|
**/
|
|
VOID
|
|
AddImageExeInfo (
|
|
IN EFI_IMAGE_EXECUTION_ACTION Action,
|
|
IN CHAR16 *Name OPTIONAL,
|
|
IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath,
|
|
IN EFI_SIGNATURE_LIST *Signature OPTIONAL,
|
|
IN UINTN SignatureSize
|
|
)
|
|
{
|
|
EFI_IMAGE_EXECUTION_INFO_TABLE *ImageExeInfoTable;
|
|
EFI_IMAGE_EXECUTION_INFO_TABLE *NewImageExeInfoTable;
|
|
EFI_IMAGE_EXECUTION_INFO *ImageExeInfoEntry;
|
|
UINTN ImageExeInfoTableSize;
|
|
UINTN NewImageExeInfoEntrySize;
|
|
UINTN NameStringLen;
|
|
UINTN DevicePathSize;
|
|
|
|
ImageExeInfoTable = NULL;
|
|
NewImageExeInfoTable = NULL;
|
|
ImageExeInfoEntry = NULL;
|
|
NameStringLen = 0;
|
|
|
|
if (DevicePath == NULL) {
|
|
return ;
|
|
}
|
|
|
|
if (Name != NULL) {
|
|
NameStringLen = StrSize (Name);
|
|
} else {
|
|
NameStringLen = sizeof (CHAR16);
|
|
}
|
|
|
|
EfiGetSystemConfigurationTable (&gEfiImageSecurityDatabaseGuid, (VOID **) &ImageExeInfoTable);
|
|
if (ImageExeInfoTable != NULL) {
|
|
//
|
|
// The table has been found!
|
|
// We must enlarge the table to accomodate the new exe info entry.
|
|
//
|
|
ImageExeInfoTableSize = GetImageExeInfoTableSize (ImageExeInfoTable);
|
|
} else {
|
|
//
|
|
// Not Found!
|
|
// We should create a new table to append to the configuration table.
|
|
//
|
|
ImageExeInfoTableSize = sizeof (EFI_IMAGE_EXECUTION_INFO_TABLE);
|
|
}
|
|
|
|
DevicePathSize = GetDevicePathSize (DevicePath);
|
|
NewImageExeInfoEntrySize = sizeof (EFI_IMAGE_EXECUTION_INFO) + NameStringLen + DevicePathSize + SignatureSize;
|
|
NewImageExeInfoTable = (EFI_IMAGE_EXECUTION_INFO_TABLE *) AllocateRuntimePool (ImageExeInfoTableSize + NewImageExeInfoEntrySize);
|
|
if (NewImageExeInfoTable == NULL) {
|
|
return ;
|
|
}
|
|
|
|
if (ImageExeInfoTable != NULL) {
|
|
CopyMem (NewImageExeInfoTable, ImageExeInfoTable, ImageExeInfoTableSize);
|
|
} else {
|
|
NewImageExeInfoTable->NumberOfImages = 0;
|
|
}
|
|
NewImageExeInfoTable->NumberOfImages++;
|
|
ImageExeInfoEntry = (EFI_IMAGE_EXECUTION_INFO *) ((UINT8 *) NewImageExeInfoTable + ImageExeInfoTableSize);
|
|
//
|
|
// Update new item's infomation.
|
|
//
|
|
WriteUnaligned32 ((UINT32 *) &ImageExeInfoEntry->Action, Action);
|
|
WriteUnaligned32 ((UINT32 *) &ImageExeInfoEntry->InfoSize, (UINT32) NewImageExeInfoEntrySize);
|
|
|
|
if (Name != NULL) {
|
|
CopyMem ((UINT8 *) &ImageExeInfoEntry->InfoSize + sizeof (UINT32), Name, NameStringLen);
|
|
} else {
|
|
ZeroMem ((UINT8 *) &ImageExeInfoEntry->InfoSize + sizeof (UINT32), sizeof (CHAR16));
|
|
}
|
|
CopyMem (
|
|
(UINT8 *) &ImageExeInfoEntry->InfoSize + sizeof (UINT32) + NameStringLen,
|
|
DevicePath,
|
|
DevicePathSize
|
|
);
|
|
if (Signature != NULL) {
|
|
CopyMem (
|
|
(UINT8 *) &ImageExeInfoEntry->InfoSize + sizeof (UINT32) + NameStringLen + DevicePathSize,
|
|
Signature,
|
|
SignatureSize
|
|
);
|
|
}
|
|
//
|
|
// Update/replace the image execution table.
|
|
//
|
|
gBS->InstallConfigurationTable (&gEfiImageSecurityDatabaseGuid, (VOID *) NewImageExeInfoTable);
|
|
|
|
//
|
|
// Free Old table data!
|
|
//
|
|
if (ImageExeInfoTable != NULL) {
|
|
FreePool (ImageExeInfoTable);
|
|
}
|
|
}
|
|
|
|
/**
|
|
Check whether signature is in specified database.
|
|
|
|
@param[in] VariableName Name of database variable that is searched in.
|
|
@param[in] Signature Pointer to signature that is searched for.
|
|
@param[in] CertType Pointer to hash algrithom.
|
|
@param[in] SignatureSize Size of Signature.
|
|
|
|
@return TRUE Found the signature in the variable database.
|
|
@return FALSE Not found the signature in the variable database.
|
|
|
|
**/
|
|
BOOLEAN
|
|
IsSignatureFoundInDatabase (
|
|
IN CHAR16 *VariableName,
|
|
IN UINT8 *Signature,
|
|
IN EFI_GUID *CertType,
|
|
IN UINTN SignatureSize
|
|
)
|
|
{
|
|
EFI_STATUS Status;
|
|
EFI_SIGNATURE_LIST *CertList;
|
|
EFI_SIGNATURE_DATA *Cert;
|
|
UINTN DataSize;
|
|
UINT8 *Data;
|
|
UINTN Index;
|
|
UINTN CertCount;
|
|
BOOLEAN IsFound;
|
|
//
|
|
// Read signature database variable.
|
|
//
|
|
IsFound = FALSE;
|
|
Data = NULL;
|
|
DataSize = 0;
|
|
Status = gRT->GetVariable (VariableName, &gEfiImageSecurityDatabaseGuid, NULL, &DataSize, NULL);
|
|
if (Status != EFI_BUFFER_TOO_SMALL) {
|
|
return FALSE;
|
|
}
|
|
|
|
Data = (UINT8 *) AllocateZeroPool (DataSize);
|
|
if (Data == NULL) {
|
|
return FALSE;
|
|
}
|
|
|
|
Status = gRT->GetVariable (VariableName, &gEfiImageSecurityDatabaseGuid, NULL, &DataSize, Data);
|
|
if (EFI_ERROR (Status)) {
|
|
goto Done;
|
|
}
|
|
//
|
|
// Enumerate all signature data in SigDB to check if executable's signature exists.
|
|
//
|
|
CertList = (EFI_SIGNATURE_LIST *) Data;
|
|
while ((DataSize > 0) && (DataSize >= CertList->SignatureListSize)) {
|
|
CertCount = (CertList->SignatureListSize - 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++) {
|
|
if (CompareMem (Cert->SignatureData, Signature, SignatureSize) == 0) {
|
|
//
|
|
// Find the signature in database.
|
|
//
|
|
IsFound = TRUE;
|
|
SecureBootHook (VariableName, &gEfiImageSecurityDatabaseGuid, CertList->SignatureSize, Cert);
|
|
break;
|
|
}
|
|
|
|
Cert = (EFI_SIGNATURE_DATA *) ((UINT8 *) Cert + CertList->SignatureSize);
|
|
}
|
|
|
|
if (IsFound) {
|
|
break;
|
|
}
|
|
}
|
|
|
|
DataSize -= CertList->SignatureListSize;
|
|
CertList = (EFI_SIGNATURE_LIST *) ((UINT8 *) CertList + CertList->SignatureListSize);
|
|
}
|
|
|
|
Done:
|
|
if (Data != NULL) {
|
|
FreePool (Data);
|
|
}
|
|
|
|
return IsFound;
|
|
}
|
|
|
|
/**
|
|
Verify PKCS#7 SignedData using certificate found in Variable which formatted
|
|
as EFI_SIGNATURE_LIST. The Variable may be PK, KEK, DB or DBX.
|
|
|
|
@param[in] AuthData Pointer to the Authenticode Signature retrieved from signed image.
|
|
@param[in] AuthDataSize Size of the Authenticode Signature in bytes.
|
|
@param[in] VariableName Name of Variable to search for Certificate.
|
|
@param[in] VendorGuid Variable vendor GUID.
|
|
|
|
@retval TRUE Image pass verification.
|
|
@retval FALSE Image fail verification.
|
|
|
|
**/
|
|
BOOLEAN
|
|
IsPkcsSignedDataVerifiedBySignatureList (
|
|
IN UINT8 *AuthData,
|
|
IN UINTN AuthDataSize,
|
|
IN CHAR16 *VariableName,
|
|
IN EFI_GUID *VendorGuid
|
|
)
|
|
{
|
|
EFI_STATUS Status;
|
|
BOOLEAN VerifyStatus;
|
|
EFI_SIGNATURE_LIST *CertList;
|
|
EFI_SIGNATURE_DATA *Cert;
|
|
UINTN DataSize;
|
|
UINT8 *Data;
|
|
UINT8 *RootCert;
|
|
UINTN RootCertSize;
|
|
UINTN Index;
|
|
UINTN CertCount;
|
|
|
|
Data = NULL;
|
|
CertList = NULL;
|
|
Cert = NULL;
|
|
RootCert = NULL;
|
|
RootCertSize = 0;
|
|
VerifyStatus = FALSE;
|
|
|
|
DataSize = 0;
|
|
Status = gRT->GetVariable (VariableName, VendorGuid, 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);
|
|
if (EFI_ERROR (Status)) {
|
|
goto Done;
|
|
}
|
|
|
|
//
|
|
// Find X509 certificate in Signature List to verify the signature in pkcs7 signed data.
|
|
//
|
|
CertList = (EFI_SIGNATURE_LIST *) Data;
|
|
while ((DataSize > 0) && (DataSize >= CertList->SignatureListSize)) {
|
|
if (CompareGuid (&CertList->SignatureType, &gEfiCertX509Guid)) {
|
|
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);
|
|
|
|
//
|
|
// Call AuthenticodeVerify library to Verify Authenticode struct.
|
|
//
|
|
VerifyStatus = AuthenticodeVerify (
|
|
AuthData,
|
|
AuthDataSize,
|
|
RootCert,
|
|
RootCertSize,
|
|
mImageDigest,
|
|
mImageDigestSize
|
|
);
|
|
if (VerifyStatus) {
|
|
SecureBootHook (VariableName, VendorGuid, CertList->SignatureSize, Cert);
|
|
goto Done;
|
|
}
|
|
Cert = (EFI_SIGNATURE_DATA *) ((UINT8 *) Cert + CertList->SignatureSize);
|
|
}
|
|
}
|
|
DataSize -= CertList->SignatureListSize;
|
|
CertList = (EFI_SIGNATURE_LIST *) ((UINT8 *) CertList + CertList->SignatureListSize);
|
|
}
|
|
}
|
|
|
|
Done:
|
|
if (Data != NULL) {
|
|
FreePool (Data);
|
|
}
|
|
|
|
return VerifyStatus;
|
|
}
|
|
|
|
/**
|
|
Provide verification service for signed images, which include both signature validation
|
|
and platform policy control. For signature types, both UEFI WIN_CERTIFICATE_UEFI_GUID and
|
|
MSFT Authenticode type signatures are supported.
|
|
|
|
In this implementation, only verify external executables when in USER MODE.
|
|
Executables from FV is bypass, so pass in AuthenticationStatus is ignored.
|
|
|
|
The image verification policy is:
|
|
If the image is signed,
|
|
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,
|
|
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
|
|
within this image buffer before use.
|
|
|
|
@param[in] AuthenticationStatus
|
|
This is the authentication status returned from the security
|
|
measurement services for the input file.
|
|
@param[in] File This is a pointer to the device path of the file that is
|
|
being dispatched. This will optionally be used for logging.
|
|
@param[in] FileBuffer File buffer matches the input file device path.
|
|
@param[in] FileSize Size of File buffer matches the input file device path.
|
|
@param[in] BootPolicy A boot policy that was used to call LoadImage() UEFI service.
|
|
|
|
@retval EFI_SUCCESS The file specified by DevicePath and non-NULL
|
|
FileBuffer did authenticate, and the platform policy dictates
|
|
that the DXE Foundation may use the file.
|
|
@retval EFI_SUCCESS The device path specified by NULL device path DevicePath
|
|
and non-NULL FileBuffer did authenticate, and the platform
|
|
policy dictates that the DXE Foundation may execute the image in
|
|
FileBuffer.
|
|
@retval EFI_OUT_RESOURCE Fail to allocate memory.
|
|
@retval EFI_SECURITY_VIOLATION The file specified by File did not authenticate, and
|
|
the platform policy dictates that File should be placed
|
|
in the untrusted state. The image has been added to the file
|
|
execution table.
|
|
@retval EFI_ACCESS_DENIED The file specified by File and FileBuffer did not
|
|
authenticate, and the platform policy dictates that the DXE
|
|
Foundation many not use File.
|
|
|
|
**/
|
|
EFI_STATUS
|
|
EFIAPI
|
|
DxeImageVerificationHandler (
|
|
IN UINT32 AuthenticationStatus,
|
|
IN CONST EFI_DEVICE_PATH_PROTOCOL *File,
|
|
IN VOID *FileBuffer,
|
|
IN UINTN FileSize,
|
|
IN BOOLEAN BootPolicy
|
|
)
|
|
{
|
|
EFI_STATUS Status;
|
|
UINT16 Magic;
|
|
EFI_IMAGE_DOS_HEADER *DosHdr;
|
|
EFI_STATUS VerifyStatus;
|
|
EFI_SIGNATURE_LIST *SignatureList;
|
|
UINTN SignatureListSize;
|
|
EFI_SIGNATURE_DATA *Signature;
|
|
EFI_IMAGE_EXECUTION_ACTION Action;
|
|
WIN_CERTIFICATE *WinCertificate;
|
|
UINT32 Policy;
|
|
UINT8 *SecureBoot;
|
|
PE_COFF_LOADER_IMAGE_CONTEXT ImageContext;
|
|
UINT32 NumberOfRvaAndSizes;
|
|
WIN_CERTIFICATE_EFI_PKCS *PkcsCertData;
|
|
WIN_CERTIFICATE_UEFI_GUID *WinCertUefiGuid;
|
|
UINT8 *AuthData;
|
|
UINTN AuthDataSize;
|
|
EFI_IMAGE_DATA_DIRECTORY *SecDataDir;
|
|
UINT32 OffSet;
|
|
|
|
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.
|
|
//
|
|
switch (GetImageType (File)) {
|
|
|
|
case IMAGE_FROM_FV:
|
|
Policy = ALWAYS_EXECUTE;
|
|
break;
|
|
|
|
case IMAGE_FROM_OPTION_ROM:
|
|
Policy = PcdGet32 (PcdOptionRomImageVerificationPolicy);
|
|
break;
|
|
|
|
case IMAGE_FROM_REMOVABLE_MEDIA:
|
|
Policy = PcdGet32 (PcdRemovableMediaImageVerificationPolicy);
|
|
break;
|
|
|
|
case IMAGE_FROM_FIXED_MEDIA:
|
|
Policy = PcdGet32 (PcdFixedMediaImageVerificationPolicy);
|
|
break;
|
|
|
|
default:
|
|
Policy = DENY_EXECUTE_ON_SECURITY_VIOLATION;
|
|
break;
|
|
}
|
|
//
|
|
// If policy is always/never execute, return directly.
|
|
//
|
|
if (Policy == ALWAYS_EXECUTE) {
|
|
return EFI_SUCCESS;
|
|
} else if (Policy == NEVER_EXECUTE) {
|
|
return EFI_ACCESS_DENIED;
|
|
}
|
|
|
|
//
|
|
// 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.
|
|
//
|
|
if (SecureBoot == NULL) {
|
|
return EFI_SUCCESS;
|
|
}
|
|
|
|
//
|
|
// Skip verification if SecureBoot is disabled.
|
|
//
|
|
if (*SecureBoot == SECURE_BOOT_MODE_DISABLE) {
|
|
FreePool (SecureBoot);
|
|
return EFI_SUCCESS;
|
|
}
|
|
FreePool (SecureBoot);
|
|
|
|
//
|
|
// Read the Dos header.
|
|
//
|
|
if (FileBuffer == NULL) {
|
|
return EFI_INVALID_PARAMETER;
|
|
}
|
|
|
|
mImageBase = (UINT8 *) FileBuffer;
|
|
mImageSize = FileSize;
|
|
|
|
ZeroMem (&ImageContext, sizeof (ImageContext));
|
|
ImageContext.Handle = (VOID *) FileBuffer;
|
|
ImageContext.ImageRead = (PE_COFF_LOADER_READ_FILE) DxeImageVerificationLibImageRead;
|
|
|
|
//
|
|
// Get information about the image being loaded
|
|
//
|
|
Status = PeCoffLoaderGetImageInfo (&ImageContext);
|
|
if (EFI_ERROR (Status)) {
|
|
//
|
|
// The information can't be got from the invalid PeImage
|
|
//
|
|
goto Done;
|
|
}
|
|
|
|
Status = EFI_ACCESS_DENIED;
|
|
|
|
DosHdr = (EFI_IMAGE_DOS_HEADER *) mImageBase;
|
|
if (DosHdr->e_magic == EFI_IMAGE_DOS_SIGNATURE) {
|
|
//
|
|
// DOS image header is present,
|
|
// so read the PE header after the DOS image header.
|
|
//
|
|
mPeCoffHeaderOffset = DosHdr->e_lfanew;
|
|
} else {
|
|
mPeCoffHeaderOffset = 0;
|
|
}
|
|
//
|
|
// Check PE/COFF image.
|
|
//
|
|
mNtHeader.Pe32 = (EFI_IMAGE_NT_HEADERS32 *) (mImageBase + mPeCoffHeaderOffset);
|
|
if (mNtHeader.Pe32->Signature != EFI_IMAGE_NT_SIGNATURE) {
|
|
//
|
|
// It is not a valid Pe/Coff file.
|
|
//
|
|
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) {
|
|
//
|
|
// Use PE32 offset.
|
|
//
|
|
NumberOfRvaAndSizes = mNtHeader.Pe32->OptionalHeader.NumberOfRvaAndSizes;
|
|
if (NumberOfRvaAndSizes > 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) {
|
|
SecDataDir = (EFI_IMAGE_DATA_DIRECTORY *) &mNtHeader.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY];
|
|
}
|
|
}
|
|
|
|
//
|
|
// Start Image Validation.
|
|
//
|
|
if (SecDataDir == NULL || SecDataDir->Size == 0) {
|
|
//
|
|
// 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)) {
|
|
goto Done;
|
|
}
|
|
|
|
if (IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE1, mImageDigest, &mCertType, mImageDigestSize)) {
|
|
//
|
|
// Image Hash is in forbidden database (DBX).
|
|
//
|
|
goto Done;
|
|
}
|
|
|
|
if (IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE, mImageDigest, &mCertType, mImageDigestSize)) {
|
|
//
|
|
// Image Hash is in allowed database (DB).
|
|
//
|
|
return EFI_SUCCESS;
|
|
}
|
|
|
|
//
|
|
// Image Hash is not found in both forbidden and allowed database.
|
|
//
|
|
goto Done;
|
|
}
|
|
|
|
//
|
|
// Verify 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.
|
|
//
|
|
for (OffSet = SecDataDir->VirtualAddress;
|
|
OffSet < (SecDataDir->VirtualAddress + SecDataDir->Size);
|
|
OffSet += WinCertificate->dwLength, OffSet += ALIGN_SIZE (OffSet)) {
|
|
WinCertificate = (WIN_CERTIFICATE *) (mImageBase + OffSet);
|
|
if ((SecDataDir->VirtualAddress + SecDataDir->Size - OffSet) <= sizeof (WIN_CERTIFICATE) ||
|
|
(SecDataDir->VirtualAddress + SecDataDir->Size - OffSet) < WinCertificate->dwLength) {
|
|
break;
|
|
}
|
|
|
|
//
|
|
// Verify the image's Authenticode signature, only DER-encoded PKCS#7 signed data is supported.
|
|
//
|
|
if (WinCertificate->wCertificateType == WIN_CERT_TYPE_PKCS_SIGNED_DATA) {
|
|
//
|
|
// The certificate is formatted as WIN_CERTIFICATE_EFI_PKCS which is described in the
|
|
// Authenticode specification.
|
|
//
|
|
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) {
|
|
//
|
|
// The certificate is formatted as WIN_CERTIFICATE_UEFI_GUID which is described in UEFI Spec.
|
|
//
|
|
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;
|
|
}
|
|
|
|
Status = HashPeImageByType (AuthData, AuthDataSize);
|
|
if (EFI_ERROR (Status)) {
|
|
continue;
|
|
}
|
|
|
|
//
|
|
// Check the digital signature against the revoked certificate in forbidden database (dbx).
|
|
//
|
|
if (IsPkcsSignedDataVerifiedBySignatureList (AuthData, AuthDataSize, EFI_IMAGE_SECURITY_DATABASE1, &gEfiImageSecurityDatabaseGuid)) {
|
|
Action = EFI_IMAGE_EXECUTION_AUTH_SIG_FAILED;
|
|
VerifyStatus = EFI_ACCESS_DENIED;
|
|
break;
|
|
}
|
|
|
|
//
|
|
// Check the digital signature against the valid certificate in allowed database (db).
|
|
//
|
|
if (EFI_ERROR (VerifyStatus)) {
|
|
if (IsPkcsSignedDataVerifiedBySignatureList (AuthData, AuthDataSize, EFI_IMAGE_SECURITY_DATABASE, &gEfiImageSecurityDatabaseGuid)) {
|
|
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;
|
|
VerifyStatus = EFI_ACCESS_DENIED;
|
|
break;
|
|
} else if (EFI_ERROR (VerifyStatus)) {
|
|
if (IsSignatureFoundInDatabase (EFI_IMAGE_SECURITY_DATABASE, mImageDigest, &mCertType, mImageDigestSize)) {
|
|
VerifyStatus = EFI_SUCCESS;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (OffSet != (SecDataDir->VirtualAddress + SecDataDir->Size)) {
|
|
//
|
|
// The Size in Certificate Table or the attribute certicate table is corrupted.
|
|
//
|
|
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) mImageDigestSize;
|
|
CopyMem (&SignatureList->SignatureType, &mCertType, sizeof (EFI_GUID));
|
|
Signature = (EFI_SIGNATURE_DATA *) ((UINT8 *) SignatureList + sizeof (EFI_SIGNATURE_LIST));
|
|
CopyMem (Signature->SignatureData, mImageDigest, mImageDigestSize);
|
|
}
|
|
}
|
|
|
|
Done:
|
|
if (Status != EFI_SUCCESS) {
|
|
//
|
|
// Policy decides to defer or reject the image; add its information in image executable information table.
|
|
//
|
|
AddImageExeInfo (Action, NULL, File, SignatureList, SignatureListSize);
|
|
Status = EFI_SECURITY_VIOLATION;
|
|
}
|
|
|
|
if (SignatureList != NULL) {
|
|
FreePool (SignatureList);
|
|
}
|
|
|
|
return Status;
|
|
}
|
|
|
|
/**
|
|
Register security measurement handler.
|
|
|
|
@param ImageHandle ImageHandle of the loaded driver.
|
|
@param SystemTable Pointer to the EFI System Table.
|
|
|
|
@retval EFI_SUCCESS The handlers were registered successfully.
|
|
**/
|
|
EFI_STATUS
|
|
EFIAPI
|
|
DxeImageVerificationLibConstructor (
|
|
IN EFI_HANDLE ImageHandle,
|
|
IN EFI_SYSTEM_TABLE *SystemTable
|
|
)
|
|
{
|
|
return RegisterSecurity2Handler (
|
|
DxeImageVerificationHandler,
|
|
EFI_AUTH_OPERATION_VERIFY_IMAGE | EFI_AUTH_OPERATION_IMAGE_REQUIRED
|
|
);
|
|
}
|