/** @file FMP Authentication PKCS7 handler. Provide generic FMP authentication functions for DXE/PEI post memory phase. Caution: This module requires additional review when modified. This module will have external input - capsule image. This external input must be validated carefully to avoid security issue like buffer overflow, integer overflow. FmpAuthenticatedHandlerPkcs7(), AuthenticateFmpImage() will receive untrusted input and do basic validation. Copyright (c) 2016, Intel Corporation. All rights reserved.<BR> This program and the accompanying materials are licensed and made available under the terms and conditions of the BSD License which accompanies this distribution. The full text of the license may be found at http://opensource.org/licenses/bsd-license.php THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. **/ #include <Uefi.h> #include <Guid/SystemResourceTable.h> #include <Guid/FirmwareContentsSigned.h> #include <Guid/WinCertificate.h> #include <Library/BaseLib.h> #include <Library/BaseMemoryLib.h> #include <Library/DebugLib.h> #include <Library/MemoryAllocationLib.h> #include <Library/BaseCryptLib.h> #include <Library/FmpAuthenticationLib.h> #include <Library/PcdLib.h> #include <Protocol/FirmwareManagement.h> #include <Guid/SystemResourceTable.h> /** The handler is used to do the authentication for FMP capsule based upon EFI_FIRMWARE_IMAGE_AUTHENTICATION. Caution: This function may receive untrusted input. This function assumes the caller AuthenticateFmpImage() already did basic validation for EFI_FIRMWARE_IMAGE_AUTHENTICATION. @param[in] Image Points to an FMP authentication image, started from EFI_FIRMWARE_IMAGE_AUTHENTICATION. @param[in] ImageSize Size of the authentication image in bytes. @param[in] PublicKeyData The public key data used to validate the signature. @param[in] PublicKeyDataLength The length of the public key data. @retval RETURN_SUCCESS Authentication pass. The LastAttemptStatus should be LAST_ATTEMPT_STATUS_SUCCESS. @retval RETURN_SECURITY_VIOLATION Authentication fail. The LastAttemptStatus should be LAST_ATTEMPT_STATUS_ERROR_AUTH_ERROR. @retval RETURN_INVALID_PARAMETER The image is in an invalid format. The LastAttemptStatus should be LAST_ATTEMPT_STATUS_ERROR_INVALID_FORMAT. @retval RETURN_OUT_OF_RESOURCES No Authentication handler associated with CertType. The LastAttemptStatus should be LAST_ATTEMPT_STATUS_ERROR_INSUFFICIENT_RESOURCES. **/ RETURN_STATUS FmpAuthenticatedHandlerPkcs7 ( IN EFI_FIRMWARE_IMAGE_AUTHENTICATION *Image, IN UINTN ImageSize, IN CONST UINT8 *PublicKeyData, IN UINTN PublicKeyDataLength ) { RETURN_STATUS Status; BOOLEAN CryptoStatus; VOID *P7Data; UINTN P7Length; VOID *TempBuffer; DEBUG((DEBUG_INFO, "FmpAuthenticatedHandlerPkcs7 - Image: 0x%08x - 0x%08x\n", (UINTN)Image, (UINTN)ImageSize)); P7Length = Image->AuthInfo.Hdr.dwLength - (OFFSET_OF(WIN_CERTIFICATE_UEFI_GUID, CertData)); P7Data = Image->AuthInfo.CertData; // It is a signature across the variable data and the Monotonic Count value. TempBuffer = AllocatePool(ImageSize - Image->AuthInfo.Hdr.dwLength); if (TempBuffer == NULL) { DEBUG((DEBUG_ERROR, "FmpAuthenticatedHandlerPkcs7: TempBuffer == NULL\n")); Status = RETURN_OUT_OF_RESOURCES; goto Done; } CopyMem( TempBuffer, (UINT8 *)Image + sizeof(Image->MonotonicCount) + Image->AuthInfo.Hdr.dwLength, ImageSize - sizeof(Image->MonotonicCount) - Image->AuthInfo.Hdr.dwLength ); CopyMem( (UINT8 *)TempBuffer + ImageSize - sizeof(Image->MonotonicCount) - Image->AuthInfo.Hdr.dwLength, &Image->MonotonicCount, sizeof(Image->MonotonicCount) ); CryptoStatus = Pkcs7Verify( P7Data, P7Length, PublicKeyData, PublicKeyDataLength, (UINT8 *)TempBuffer, ImageSize - Image->AuthInfo.Hdr.dwLength ); FreePool(TempBuffer); if (!CryptoStatus) { // // If PKCS7 signature verification fails, AUTH tested failed bit is set. // DEBUG((DEBUG_ERROR, "FmpAuthenticatedHandlerPkcs7: Pkcs7Verify() failed\n")); Status = RETURN_SECURITY_VIOLATION; goto Done; } DEBUG((DEBUG_INFO, "FmpAuthenticatedHandlerPkcs7: PASS verification\n")); Status = RETURN_SUCCESS; Done: return Status; } /** The function is used to do the authentication for FMP capsule based upon EFI_FIRMWARE_IMAGE_AUTHENTICATION. The FMP capsule image should start with EFI_FIRMWARE_IMAGE_AUTHENTICATION, followed by the payload. If the return status is RETURN_SUCCESS, the caller may continue the rest FMP update process. If the return status is NOT RETURN_SUCCESS, the caller should stop the FMP update process and convert the return status to LastAttemptStatus to indicate that FMP update fails. The LastAttemptStatus can be got from ESRT table or via EFI_FIRMWARE_MANAGEMENT_PROTOCOL.GetImageInfo(). Caution: This function may receive untrusted input. @param[in] Image Points to an FMP authentication image, started from EFI_FIRMWARE_IMAGE_AUTHENTICATION. @param[in] ImageSize Size of the authentication image in bytes. @param[in] PublicKeyData The public key data used to validate the signature. @param[in] PublicKeyDataLength The length of the public key data. @retval RETURN_SUCCESS Authentication pass. The LastAttemptStatus should be LAST_ATTEMPT_STATUS_SUCCESS. @retval RETURN_SECURITY_VIOLATION Authentication fail. The LastAttemptStatus should be LAST_ATTEMPT_STATUS_ERROR_AUTH_ERROR. @retval RETURN_INVALID_PARAMETER The image is in an invalid format. The LastAttemptStatus should be LAST_ATTEMPT_STATUS_ERROR_INVALID_FORMAT. @retval RETURN_UNSUPPORTED No Authentication handler associated with CertType. The LastAttemptStatus should be LAST_ATTEMPT_STATUS_ERROR_INVALID_FORMAT. @retval RETURN_UNSUPPORTED Image or ImageSize is invalid. The LastAttemptStatus should be LAST_ATTEMPT_STATUS_ERROR_INVALID_FORMAT. @retval RETURN_OUT_OF_RESOURCES No Authentication handler associated with CertType. The LastAttemptStatus should be LAST_ATTEMPT_STATUS_ERROR_INSUFFICIENT_RESOURCES. **/ RETURN_STATUS EFIAPI AuthenticateFmpImage ( IN EFI_FIRMWARE_IMAGE_AUTHENTICATION *Image, IN UINTN ImageSize, IN CONST UINT8 *PublicKeyData, IN UINTN PublicKeyDataLength ) { GUID *CertType; EFI_STATUS Status; if ((Image == NULL) || (ImageSize == 0)) { return RETURN_UNSUPPORTED; } if (ImageSize < sizeof(EFI_FIRMWARE_IMAGE_AUTHENTICATION)) { DEBUG((DEBUG_ERROR, "AuthenticateFmpImage - ImageSize too small\n")); return RETURN_INVALID_PARAMETER; } if (Image->AuthInfo.Hdr.dwLength <= OFFSET_OF(WIN_CERTIFICATE_UEFI_GUID, CertData)) { DEBUG((DEBUG_ERROR, "AuthenticateFmpImage - dwLength too small\n")); return RETURN_INVALID_PARAMETER; } if (Image->AuthInfo.Hdr.dwLength > MAX_UINTN - sizeof(UINT64)) { DEBUG((DEBUG_ERROR, "AuthenticateFmpImage - dwLength too big\n")); return RETURN_INVALID_PARAMETER; } if (ImageSize <= sizeof(Image->MonotonicCount) + Image->AuthInfo.Hdr.dwLength) { DEBUG((DEBUG_ERROR, "AuthenticateFmpImage - ImageSize too small\n")); return RETURN_INVALID_PARAMETER; } if (Image->AuthInfo.Hdr.wRevision != 0x0200) { DEBUG((DEBUG_ERROR, "AuthenticateFmpImage - wRevision: 0x%02x, expect - 0x%02x\n", (UINTN)Image->AuthInfo.Hdr.wRevision, (UINTN)0x0200)); return RETURN_INVALID_PARAMETER; } if (Image->AuthInfo.Hdr.wCertificateType != WIN_CERT_TYPE_EFI_GUID) { DEBUG((DEBUG_ERROR, "AuthenticateFmpImage - wCertificateType: 0x%02x, expect - 0x%02x\n", (UINTN)Image->AuthInfo.Hdr.wCertificateType, (UINTN)WIN_CERT_TYPE_EFI_GUID)); return RETURN_INVALID_PARAMETER; } CertType = &Image->AuthInfo.CertType; DEBUG((DEBUG_INFO, "AuthenticateFmpImage - CertType: %g\n", CertType)); if (CompareGuid (&gEfiCertPkcs7Guid, CertType)) { // // Call the match handler to extract raw data for the input section data. // Status = FmpAuthenticatedHandlerPkcs7 ( Image, ImageSize, PublicKeyData, PublicKeyDataLength ); return Status; } // // Not found, the input guided section is not supported. // return RETURN_UNSUPPORTED; }