| /** @file | |
| Library implementing the LockBox interface for OVMF | |
| Copyright (C) 2013, Red Hat, Inc. | |
| Copyright (c) 2010 - 2014, 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 <Library/BaseMemoryLib.h> | |
| #include <Library/DebugLib.h> | |
| #include <Library/LockBoxLib.h> | |
| #include <Library/PcdLib.h> | |
| #include <LockBoxLib.h> | |
| #pragma pack(1) | |
| typedef struct { | |
| EFI_GUID Guid; | |
| EFI_PHYSICAL_ADDRESS OrigAddress; | |
| EFI_PHYSICAL_ADDRESS CopyAddress; | |
| UINT32 Size; | |
| UINT64 Attributes; | |
| } LOCK_BOX_ENTRY; | |
| #pragma pack() | |
| LOCK_BOX_GLOBAL *mLockBoxGlobal = NULL; | |
| STATIC LOCK_BOX_ENTRY *StartOfEntries = NULL; | |
| STATIC LOCK_BOX_ENTRY *EndOfEntries = NULL; | |
| RETURN_STATUS | |
| EFIAPI | |
| LockBoxLibInitialize ( | |
| VOID | |
| ) | |
| { | |
| UINTN NumEntries; | |
| ASSERT (!FeaturePcdGet (PcdSmmSmramRequire)); | |
| if (PcdGet32 (PcdOvmfLockBoxStorageSize) < sizeof (LOCK_BOX_GLOBAL)) { | |
| return RETURN_UNSUPPORTED; | |
| } | |
| mLockBoxGlobal = (LOCK_BOX_GLOBAL *)(UINTN) PcdGet32 (PcdOvmfLockBoxStorageBase); | |
| StartOfEntries = ((LOCK_BOX_ENTRY *) (mLockBoxGlobal + 1)); | |
| NumEntries = ((PcdGet32 (PcdOvmfLockBoxStorageSize) - sizeof (LOCK_BOX_GLOBAL)) / | |
| sizeof (LOCK_BOX_ENTRY)); | |
| EndOfEntries = StartOfEntries + NumEntries; | |
| if (mLockBoxGlobal->Signature != LOCK_BOX_GLOBAL_SIGNATURE) { | |
| // | |
| // Note: This code depends on the lock box being cleared in early | |
| // PEI before usage, so the SubPageBuffer and SubPageRemaining | |
| // fields don't need to be set to 0. | |
| // | |
| mLockBoxGlobal->Signature = LOCK_BOX_GLOBAL_SIGNATURE; | |
| } | |
| return RETURN_SUCCESS; | |
| } | |
| /** | |
| Find LockBox entry based on GUID. | |
| @param[in] Guid The GUID to search for. | |
| @return Address of the LOCK_BOX_ENTRY found. | |
| If NULL, then the item was not found, and there is no space | |
| left to store a new item. | |
| If non-NULL and LOCK_BOX_ENTRY.Size == 0, then the item was not | |
| found, but a new item can be inserted at the returned location. | |
| If non-NULL and LOCK_BOX_ENTRY.Size > 0, then the item was found. | |
| **/ | |
| STATIC | |
| LOCK_BOX_ENTRY * | |
| EFIAPI | |
| FindHeaderByGuid ( | |
| IN CONST EFI_GUID *Guid | |
| ) | |
| { | |
| LOCK_BOX_ENTRY *Header; | |
| for (Header = StartOfEntries; Header < EndOfEntries; Header++) { | |
| if (Header->Size == 0 || CompareGuid (Guid, &Header->Guid)) { | |
| return Header; | |
| } | |
| } | |
| return NULL; | |
| } | |
| /** | |
| This function will save confidential information to lockbox. | |
| @param Guid the guid to identify the confidential information | |
| @param Buffer the address of the confidential information | |
| @param Length the length of the confidential information | |
| @retval RETURN_SUCCESS the information is saved successfully. | |
| @retval RETURN_INVALID_PARAMETER the Guid is NULL, or Buffer is NULL, or | |
| Length is 0 | |
| @retval RETURN_ALREADY_STARTED the requested GUID already exist. | |
| @retval RETURN_OUT_OF_RESOURCES no enough resource to save the information. | |
| @retval RETURN_ACCESS_DENIED it is too late to invoke this interface | |
| @retval RETURN_NOT_STARTED it is too early to invoke this interface | |
| @retval RETURN_UNSUPPORTED the service is not supported by | |
| implementaion. | |
| **/ | |
| RETURN_STATUS | |
| EFIAPI | |
| SaveLockBox ( | |
| IN GUID *Guid, | |
| IN VOID *Buffer, | |
| IN UINTN Length | |
| ) | |
| { | |
| LOCK_BOX_ENTRY *Header; | |
| VOID *CopyBuffer; | |
| DEBUG ((DEBUG_VERBOSE, "%a: Guid=%g Buffer=%p Length=0x%x\n", __FUNCTION__, | |
| Guid, Buffer, (UINT32) Length)); | |
| if (Guid == NULL || Buffer == NULL || Length == 0) { | |
| return RETURN_INVALID_PARAMETER; | |
| } | |
| if (Length > 0xFFFFFFFF) { | |
| return RETURN_OUT_OF_RESOURCES; | |
| } | |
| Header = FindHeaderByGuid (Guid); | |
| if (Header == NULL) { | |
| return RETURN_OUT_OF_RESOURCES; | |
| } | |
| if (Header->Size > 0) { | |
| return RETURN_ALREADY_STARTED; | |
| } | |
| CopyBuffer = AllocateAcpiNvsPool (Length); | |
| if (CopyBuffer == NULL) { | |
| return RETURN_OUT_OF_RESOURCES; | |
| } | |
| // | |
| // overwrite the current terminator header with new metadata | |
| // | |
| CopyGuid (&Header->Guid, Guid); | |
| Header->OrigAddress = (UINTN) Buffer; | |
| Header->CopyAddress = (UINTN) CopyBuffer; | |
| Header->Size = (UINT32) Length; | |
| Header->Attributes = 0; | |
| // | |
| // copy contents | |
| // | |
| CopyMem (CopyBuffer, Buffer, Length); | |
| return RETURN_SUCCESS; | |
| } | |
| /** | |
| This function will set lockbox attributes. | |
| @param Guid the guid to identify the confidential information | |
| @param Attributes the attributes of the lockbox | |
| @retval RETURN_SUCCESS the information is saved successfully. | |
| @retval RETURN_INVALID_PARAMETER attributes is invalid. | |
| @retval RETURN_NOT_FOUND the requested GUID not found. | |
| @retval RETURN_ACCESS_DENIED it is too late to invoke this interface | |
| @retval RETURN_NOT_STARTED it is too early to invoke this interface | |
| @retval RETURN_UNSUPPORTED the service is not supported by | |
| implementaion. | |
| **/ | |
| RETURN_STATUS | |
| EFIAPI | |
| SetLockBoxAttributes ( | |
| IN GUID *Guid, | |
| IN UINT64 Attributes | |
| ) | |
| { | |
| LOCK_BOX_ENTRY *Header; | |
| DEBUG ((DEBUG_VERBOSE, "%a: Guid=%g Attributes=0x%Lx\n", __FUNCTION__, Guid, | |
| Attributes)); | |
| if (Guid == NULL) { | |
| return RETURN_INVALID_PARAMETER; | |
| } | |
| Header = FindHeaderByGuid (Guid); | |
| if (!Header || Header->Size == 0) { | |
| return RETURN_NOT_FOUND; | |
| } | |
| Header->Attributes = Attributes; | |
| return RETURN_SUCCESS; | |
| } | |
| /** | |
| This function will update confidential information to lockbox. | |
| @param Guid the guid to identify the original confidential information | |
| @param Offset the offset of the original confidential information | |
| @param Buffer the address of the updated confidential information | |
| @param Length the length of the updated confidential information | |
| @retval RETURN_SUCCESS the information is saved successfully. | |
| @retval RETURN_INVALID_PARAMETER the Guid is NULL, or Buffer is NULL, or | |
| Length is 0. | |
| @retval RETURN_NOT_FOUND the requested GUID not found. | |
| @retval RETURN_BUFFER_TOO_SMALL the original buffer to too small to hold | |
| new information. | |
| @retval RETURN_ACCESS_DENIED it is too late to invoke this interface | |
| @retval RETURN_NOT_STARTED it is too early to invoke this interface | |
| @retval RETURN_UNSUPPORTED the service is not supported by | |
| implementaion. | |
| **/ | |
| RETURN_STATUS | |
| EFIAPI | |
| UpdateLockBox ( | |
| IN GUID *Guid, | |
| IN UINTN Offset, | |
| IN VOID *Buffer, | |
| IN UINTN Length | |
| ) | |
| { | |
| LOCK_BOX_ENTRY *Header; | |
| DEBUG ((DEBUG_VERBOSE, "%a: Guid=%g Offset=0x%x Length=0x%x\n", __FUNCTION__, | |
| Guid, (UINT32) Offset, (UINT32) Length)); | |
| if (Guid == NULL || Buffer == NULL || Length == 0) { | |
| return RETURN_INVALID_PARAMETER; | |
| } | |
| Header = FindHeaderByGuid (Guid); | |
| if (!Header || Header->Size == 0) { | |
| return RETURN_NOT_FOUND; | |
| } | |
| if (Header->Size < Offset || | |
| Length > Header->Size - Offset) { | |
| return RETURN_BUFFER_TOO_SMALL; | |
| } | |
| CopyMem ((UINT8 *)(UINTN) (Header->CopyAddress) + Offset, Buffer, Length); | |
| return RETURN_SUCCESS; | |
| } | |
| /** | |
| This function will restore confidential information from lockbox. | |
| @param Guid the guid to identify the confidential information | |
| @param Buffer the address of the restored confidential information | |
| NULL means restored to original address, Length MUST be NULL at | |
| same time. | |
| @param Length the length of the restored confidential information | |
| @retval RETURN_SUCCESS the information is restored successfully. | |
| @retval RETURN_INVALID_PARAMETER the Guid is NULL, or one of Buffer and | |
| Length is NULL. | |
| @retval RETURN_WRITE_PROTECTED Buffer and Length are NULL, but the LockBox | |
| has no LOCK_BOX_ATTRIBUTE_RESTORE_IN_PLACE | |
| attribute. | |
| @retval RETURN_BUFFER_TOO_SMALL the Length is too small to hold the | |
| confidential information. | |
| @retval RETURN_NOT_FOUND the requested GUID not found. | |
| @retval RETURN_NOT_STARTED it is too early to invoke this interface | |
| @retval RETURN_ACCESS_DENIED not allow to restore to the address | |
| @retval RETURN_UNSUPPORTED the service is not supported by | |
| implementaion. | |
| **/ | |
| RETURN_STATUS | |
| EFIAPI | |
| RestoreLockBox ( | |
| IN GUID *Guid, | |
| IN VOID *Buffer, OPTIONAL | |
| IN OUT UINTN *Length OPTIONAL | |
| ) | |
| { | |
| LOCK_BOX_ENTRY *Header; | |
| DEBUG ((DEBUG_VERBOSE, "%a: Guid=%g Buffer=%p\n", __FUNCTION__, Guid, | |
| Buffer)); | |
| if ((Guid == NULL) || | |
| ((Buffer == NULL) && (Length != NULL)) || | |
| ((Buffer != NULL) && (Length == NULL))) { | |
| return EFI_INVALID_PARAMETER; | |
| } | |
| Header = FindHeaderByGuid (Guid); | |
| if (!Header || Header->Size == 0) { | |
| return RETURN_NOT_FOUND; | |
| } | |
| if (Buffer == NULL) { | |
| if (!(Header->Attributes & LOCK_BOX_ATTRIBUTE_RESTORE_IN_PLACE)) { | |
| return RETURN_WRITE_PROTECTED; | |
| } | |
| if (Header->OrigAddress + (Header->Size - 1) > MAX_ADDRESS) { | |
| return RETURN_UNSUPPORTED; | |
| } | |
| Buffer = (VOID *)(UINTN) Header->OrigAddress; | |
| } | |
| // | |
| // Set RestoreLength | |
| // | |
| if (Length != NULL) { | |
| if (Header->Size > *Length) { | |
| // | |
| // Input buffer is too small to hold all data. | |
| // | |
| *Length = Header->Size; | |
| return EFI_BUFFER_TOO_SMALL; | |
| } | |
| *Length = Header->Size; | |
| } | |
| CopyMem (Buffer, (VOID*)(UINTN) Header->CopyAddress, Header->Size); | |
| return RETURN_SUCCESS; | |
| } | |
| /** | |
| This function will restore confidential information from all lockbox which | |
| have RestoreInPlace attribute. | |
| @retval RETURN_SUCCESS the information is restored successfully. | |
| @retval RETURN_NOT_STARTED it is too early to invoke this interface | |
| @retval RETURN_UNSUPPORTED the service is not supported by | |
| implementaion. | |
| **/ | |
| RETURN_STATUS | |
| EFIAPI | |
| RestoreAllLockBoxInPlace ( | |
| VOID | |
| ) | |
| { | |
| LOCK_BOX_ENTRY *Header; | |
| for (Header = StartOfEntries; | |
| Header < EndOfEntries && Header->Size > 0; | |
| Header++) { | |
| if (Header->Attributes & LOCK_BOX_ATTRIBUTE_RESTORE_IN_PLACE) { | |
| VOID *Buffer; | |
| if (Header->OrigAddress + (Header->Size - 1) > MAX_ADDRESS) { | |
| return RETURN_UNSUPPORTED; | |
| } | |
| Buffer = (VOID *)(UINTN) Header->OrigAddress; | |
| CopyMem (Buffer, (VOID*)(UINTN)Header->CopyAddress, Header->Size); | |
| DEBUG ((DEBUG_VERBOSE, "%a: Guid=%g Buffer=%p\n", __FUNCTION__, | |
| &Header->Guid, Buffer)); | |
| } | |
| } | |
| return RETURN_SUCCESS; | |
| } |