/** @file FMP Authentication RSA2048SHA256 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. FmpAuthenticatedHandlerRsa2048Sha256(), 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> /// /// Public Exponent of RSA Key. /// STATIC CONST UINT8 mRsaE[] = { 0x01, 0x00, 0x01 }; /** 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 FmpAuthenticatedHandlerRsa2048Sha256 ( IN EFI_FIRMWARE_IMAGE_AUTHENTICATION *Image, IN UINTN ImageSize, IN CONST UINT8 *PublicKeyData, IN UINTN PublicKeyDataLength ) { RETURN_STATUS Status; EFI_CERT_BLOCK_RSA_2048_SHA256 *CertBlockRsa2048Sha256; BOOLEAN CryptoStatus; UINT8 Digest[SHA256_DIGEST_SIZE]; UINT8 *PublicKey; UINTN PublicKeyBufferSize; VOID *HashContext; VOID *Rsa; DEBUG ((DEBUG_INFO, "FmpAuthenticatedHandlerRsa2048Sha256 - Image: 0x%08x - 0x%08x\n", (UINTN)Image, (UINTN)ImageSize)); if (Image->AuthInfo.Hdr.dwLength != OFFSET_OF(WIN_CERTIFICATE_UEFI_GUID, CertData) + sizeof(EFI_CERT_BLOCK_RSA_2048_SHA256)) { DEBUG((DEBUG_ERROR, "FmpAuthenticatedHandlerRsa2048Sha256 - dwLength: 0x%04x, dwLength - 0x%04x\n", (UINTN)Image->AuthInfo.Hdr.dwLength, (UINTN)OFFSET_OF(WIN_CERTIFICATE_UEFI_GUID, CertData) + sizeof(EFI_CERT_BLOCK_RSA_2048_SHA256))); return RETURN_INVALID_PARAMETER; } CertBlockRsa2048Sha256 = (EFI_CERT_BLOCK_RSA_2048_SHA256 *)Image->AuthInfo.CertData; if (!CompareGuid(&CertBlockRsa2048Sha256->HashType, &gEfiHashAlgorithmSha256Guid)) { DEBUG((DEBUG_ERROR, "FmpAuthenticatedHandlerRsa2048Sha256 - HashType: %g, expect - %g\n", &CertBlockRsa2048Sha256->HashType, &gEfiHashAlgorithmSha256Guid)); return RETURN_INVALID_PARAMETER; } HashContext = NULL; Rsa = NULL; // // Allocate hash context buffer required for SHA 256 // HashContext = AllocatePool (Sha256GetContextSize ()); if (HashContext == NULL) { CryptoStatus = FALSE; DEBUG ((DEBUG_ERROR, "FmpAuthenticatedHandlerRsa2048Sha256: Can not allocate hash context\n")); Status = RETURN_OUT_OF_RESOURCES; goto Done; } // // Hash public key from data payload with SHA256. // ZeroMem (Digest, SHA256_DIGEST_SIZE); CryptoStatus = Sha256Init (HashContext); if (!CryptoStatus) { DEBUG ((DEBUG_ERROR, "FmpAuthenticatedHandlerRsa2048Sha256: Sha256Init() failed\n")); Status = RETURN_OUT_OF_RESOURCES; goto Done; } CryptoStatus = Sha256Update (HashContext, &CertBlockRsa2048Sha256->PublicKey, sizeof(CertBlockRsa2048Sha256->PublicKey)); if (!CryptoStatus) { DEBUG ((DEBUG_ERROR, "FmpAuthenticatedHandlerRsa2048Sha256: Sha256Update() failed\n")); Status = RETURN_OUT_OF_RESOURCES; goto Done; } CryptoStatus = Sha256Final (HashContext, Digest); if (!CryptoStatus) { DEBUG ((DEBUG_ERROR, "FmpAuthenticatedHandlerRsa2048Sha256: Sha256Final() failed\n")); Status = RETURN_OUT_OF_RESOURCES; goto Done; } // // Fail if the PublicKey is not one of the public keys in PcdRsa2048Sha256PublicKeyBuffer // PublicKey = (VOID *)PublicKeyData; PublicKeyBufferSize = PublicKeyDataLength; CryptoStatus = FALSE; while (PublicKeyBufferSize != 0) { if (CompareMem (Digest, PublicKey, SHA256_DIGEST_SIZE) == 0) { CryptoStatus = TRUE; break; } PublicKey = PublicKey + SHA256_DIGEST_SIZE; PublicKeyBufferSize = PublicKeyBufferSize - SHA256_DIGEST_SIZE; } if (!CryptoStatus) { DEBUG ((DEBUG_ERROR, "FmpAuthenticatedHandlerRsa2048Sha256: Public key in section is not supported\n")); Status = RETURN_SECURITY_VIOLATION; goto Done; } // // Generate & Initialize RSA Context. // Rsa = RsaNew (); if (Rsa == NULL) { CryptoStatus = FALSE; DEBUG ((DEBUG_ERROR, "FmpAuthenticatedHandlerRsa2048Sha256: RsaNew() failed\n")); Status = RETURN_OUT_OF_RESOURCES; goto Done; } // // Set RSA Key Components. // NOTE: Only N and E are needed to be set as RSA public key for signature verification. // CryptoStatus = RsaSetKey (Rsa, RsaKeyN, CertBlockRsa2048Sha256->PublicKey, sizeof(CertBlockRsa2048Sha256->PublicKey)); if (!CryptoStatus) { DEBUG ((DEBUG_ERROR, "FmpAuthenticatedHandlerRsa2048Sha256: RsaSetKey(RsaKeyN) failed\n")); Status = RETURN_OUT_OF_RESOURCES; goto Done; } CryptoStatus = RsaSetKey (Rsa, RsaKeyE, mRsaE, sizeof (mRsaE)); if (!CryptoStatus) { DEBUG ((DEBUG_ERROR, "FmpAuthenticatedHandlerRsa2048Sha256: RsaSetKey(RsaKeyE) failed\n")); Status = RETURN_OUT_OF_RESOURCES; goto Done; } // // Hash data payload with SHA256. // ZeroMem (Digest, SHA256_DIGEST_SIZE); CryptoStatus = Sha256Init (HashContext); if (!CryptoStatus) { DEBUG ((DEBUG_ERROR, "FmpAuthenticatedHandlerRsa2048Sha256: Sha256Init() failed\n")); Status = RETURN_OUT_OF_RESOURCES; goto Done; } // It is a signature across the variable data and the Monotonic Count value. CryptoStatus = Sha256Update ( HashContext, (UINT8 *)Image + sizeof(Image->MonotonicCount) + Image->AuthInfo.Hdr.dwLength, ImageSize - sizeof(Image->MonotonicCount) - Image->AuthInfo.Hdr.dwLength ); if (!CryptoStatus) { DEBUG((DEBUG_ERROR, "FmpAuthenticatedHandlerRsa2048Sha256: Sha256Update() failed\n")); Status = RETURN_OUT_OF_RESOURCES; goto Done; } CryptoStatus = Sha256Update ( HashContext, (UINT8 *)&Image->MonotonicCount, sizeof(Image->MonotonicCount) ); if (!CryptoStatus) { DEBUG ((DEBUG_ERROR, "FmpAuthenticatedHandlerRsa2048Sha256: Sha256Update() failed\n")); Status = RETURN_OUT_OF_RESOURCES; goto Done; } CryptoStatus = Sha256Final (HashContext, Digest); if (!CryptoStatus) { DEBUG ((DEBUG_ERROR, "FmpAuthenticatedHandlerRsa2048Sha256: Sha256Final() failed\n")); Status = RETURN_OUT_OF_RESOURCES; goto Done; } // // Verify the RSA 2048 SHA 256 signature. // CryptoStatus = RsaPkcs1Verify ( Rsa, Digest, SHA256_DIGEST_SIZE, CertBlockRsa2048Sha256->Signature, sizeof (CertBlockRsa2048Sha256->Signature) ); if (!CryptoStatus) { // // If RSA 2048 SHA 256 signature verification fails, AUTH tested failed bit is set. // DEBUG ((DEBUG_ERROR, "FmpAuthenticatedHandlerRsa2048Sha256: RsaPkcs1Verify() failed\n")); Status = RETURN_SECURITY_VIOLATION; goto Done; } DEBUG ((DEBUG_INFO, "FmpAuthenticatedHandlerRsa2048Sha256: PASS verification\n")); Status = RETURN_SUCCESS; Done: // // Free allocated resources used to perform RSA 2048 SHA 256 signature verification // if (Rsa != NULL) { RsaFree (Rsa); } if (HashContext != NULL) { FreePool (HashContext); } 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 ((PublicKeyDataLength % SHA256_DIGEST_SIZE) != 0) { DEBUG ((DEBUG_ERROR, "PublicKeyDataLength is not multiple SHA256 size\n")); 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 (&gEfiCertTypeRsa2048Sha256Guid, CertType)) { // // Call the match handler to extract raw data for the input section data. // Status = FmpAuthenticatedHandlerRsa2048Sha256 ( Image, ImageSize, PublicKeyData, PublicKeyDataLength ); return Status; } // // Not found, the input guided section is not supported. // return RETURN_UNSUPPORTED; }