--- /dev/null
+/** @file -- VariablePolicySmmDxe.c\r
+This protocol allows communication with Variable Policy Engine.\r
+\r
+Copyright (c) Microsoft Corporation.\r
+SPDX-License-Identifier: BSD-2-Clause-Patent\r
+\r
+**/\r
+\r
+#include <Library/BaseLib.h>\r
+#include <Library/UefiLib.h>\r
+#include <Library/DebugLib.h>\r
+#include <Library/SafeIntLib.h>\r
+#include <Library/UefiBootServicesTableLib.h>\r
+#include <Library/BaseMemoryLib.h>\r
+#include <Library/MemoryAllocationLib.h>\r
+\r
+#include <Protocol/VariablePolicy.h>\r
+#include <Protocol/MmCommunication2.h>\r
+\r
+#include <Guid/VarCheckPolicyMmi.h>\r
+\r
+#include "Variable.h"\r
+\r
+EDKII_VARIABLE_POLICY_PROTOCOL mVariablePolicyProtocol;\r
+EFI_MM_COMMUNICATION2_PROTOCOL *mMmCommunication;\r
+\r
+VOID *mMmCommunicationBuffer;\r
+UINTN mMmCommunicationBufferSize;\r
+EFI_LOCK mMmCommunicationLock;\r
+\r
+/**\r
+ Internal helper function to consolidate communication method.\r
+\r
+ @param[in,out] CommBuffer\r
+ @param[in,out] CommSize Size of the CommBuffer.\r
+\r
+ @retval EFI_STATUS Result from communication method.\r
+\r
+**/\r
+STATIC\r
+EFI_STATUS\r
+InternalMmCommunicate (\r
+ IN OUT VOID *CommBuffer,\r
+ IN OUT UINTN *CommSize\r
+ )\r
+{\r
+ EFI_STATUS Status;\r
+ if (CommBuffer == NULL || CommSize == NULL) {\r
+ return EFI_INVALID_PARAMETER;\r
+ }\r
+ Status = mMmCommunication->Communicate (mMmCommunication, CommBuffer, CommBuffer, CommSize);\r
+ return Status;\r
+}\r
+\r
+\r
+/**\r
+ This API function disables the variable policy enforcement. If it's\r
+ already been called once, will return EFI_ALREADY_STARTED.\r
+\r
+ @retval EFI_SUCCESS\r
+ @retval EFI_ALREADY_STARTED Has already been called once this boot.\r
+ @retval EFI_WRITE_PROTECTED Interface has been locked until reboot.\r
+ @retval EFI_WRITE_PROTECTED Interface option is disabled by platform PCD.\r
+\r
+**/\r
+STATIC\r
+EFI_STATUS\r
+EFIAPI\r
+ProtocolDisableVariablePolicy (\r
+ VOID\r
+ )\r
+{\r
+ EFI_STATUS Status;\r
+ EFI_MM_COMMUNICATE_HEADER *CommHeader;\r
+ VAR_CHECK_POLICY_COMM_HEADER *PolicyHeader;\r
+ UINTN BufferSize;\r
+\r
+ // Check the PCD for convenience.\r
+ // This would also be rejected by the lib, but why go to MM if we don't have to?\r
+ if (!PcdGetBool (PcdAllowVariablePolicyEnforcementDisable)) {\r
+ return EFI_WRITE_PROTECTED;\r
+ }\r
+\r
+ AcquireLockOnlyAtBootTime (&mMmCommunicationLock);\r
+\r
+ // Set up the MM communication.\r
+ BufferSize = mMmCommunicationBufferSize;\r
+ CommHeader = mMmCommunicationBuffer;\r
+ PolicyHeader = (VAR_CHECK_POLICY_COMM_HEADER*)&CommHeader->Data;\r
+ CopyGuid( &CommHeader->HeaderGuid, &gVarCheckPolicyLibMmiHandlerGuid );\r
+ CommHeader->MessageLength = BufferSize;\r
+ PolicyHeader->Signature = VAR_CHECK_POLICY_COMM_SIG;\r
+ PolicyHeader->Revision = VAR_CHECK_POLICY_COMM_REVISION;\r
+ PolicyHeader->Command = VAR_CHECK_POLICY_COMMAND_DISABLE;\r
+\r
+ Status = InternalMmCommunicate (CommHeader, &BufferSize);\r
+ DEBUG(( DEBUG_VERBOSE, "%a - MmCommunication returned %r.\n", __FUNCTION__, Status ));\r
+\r
+ ReleaseLockOnlyAtBootTime (&mMmCommunicationLock);\r
+\r
+ return (EFI_ERROR( Status )) ? Status : PolicyHeader->Result;\r
+}\r
+\r
+\r
+/**\r
+ This API function returns whether or not the policy engine is\r
+ currently being enforced.\r
+\r
+ @param[out] State Pointer to a return value for whether the policy enforcement\r
+ is currently enabled.\r
+\r
+ @retval EFI_SUCCESS\r
+ @retval Others An error has prevented this command from completing.\r
+\r
+**/\r
+STATIC\r
+EFI_STATUS\r
+EFIAPI\r
+ProtocolIsVariablePolicyEnabled (\r
+ OUT BOOLEAN *State\r
+ )\r
+{\r
+ EFI_STATUS Status;\r
+ EFI_MM_COMMUNICATE_HEADER *CommHeader;\r
+ VAR_CHECK_POLICY_COMM_HEADER *PolicyHeader;\r
+ VAR_CHECK_POLICY_COMM_IS_ENABLED_PARAMS *CommandParams;\r
+ UINTN BufferSize;\r
+\r
+ if (State == NULL) {\r
+ return EFI_INVALID_PARAMETER;\r
+ }\r
+\r
+ AcquireLockOnlyAtBootTime (&mMmCommunicationLock);\r
+\r
+ // Set up the MM communication.\r
+ BufferSize = mMmCommunicationBufferSize;\r
+ CommHeader = mMmCommunicationBuffer;\r
+ PolicyHeader = (VAR_CHECK_POLICY_COMM_HEADER*)&CommHeader->Data;\r
+ CommandParams = (VAR_CHECK_POLICY_COMM_IS_ENABLED_PARAMS*)(PolicyHeader + 1);\r
+ CopyGuid( &CommHeader->HeaderGuid, &gVarCheckPolicyLibMmiHandlerGuid );\r
+ CommHeader->MessageLength = BufferSize;\r
+ PolicyHeader->Signature = VAR_CHECK_POLICY_COMM_SIG;\r
+ PolicyHeader->Revision = VAR_CHECK_POLICY_COMM_REVISION;\r
+ PolicyHeader->Command = VAR_CHECK_POLICY_COMMAND_IS_ENABLED;\r
+\r
+ Status = InternalMmCommunicate (CommHeader, &BufferSize);\r
+ DEBUG(( DEBUG_VERBOSE, "%a - MmCommunication returned %r.\n", __FUNCTION__, Status ));\r
+\r
+ if (!EFI_ERROR( Status )) {\r
+ Status = PolicyHeader->Result;\r
+ *State = CommandParams->State;\r
+ }\r
+\r
+ ReleaseLockOnlyAtBootTime (&mMmCommunicationLock);\r
+\r
+ return Status;\r
+}\r
+\r
+\r
+/**\r
+ This API function validates and registers a new policy with\r
+ the policy enforcement engine.\r
+\r
+ @param[in] NewPolicy Pointer to the incoming policy structure.\r
+\r
+ @retval EFI_SUCCESS\r
+ @retval EFI_INVALID_PARAMETER NewPolicy is NULL or is internally inconsistent.\r
+ @retval EFI_ALREADY_STARTED An identical matching policy already exists.\r
+ @retval EFI_WRITE_PROTECTED The interface has been locked until the next reboot.\r
+ @retval EFI_UNSUPPORTED Policy enforcement has been disabled. No reason to add more policies.\r
+ @retval EFI_ABORTED A calculation error has prevented this function from completing.\r
+ @retval EFI_OUT_OF_RESOURCES Cannot grow the table to hold any more policies.\r
+\r
+**/\r
+STATIC\r
+EFI_STATUS\r
+EFIAPI\r
+ProtocolRegisterVariablePolicy (\r
+ IN CONST VARIABLE_POLICY_ENTRY *NewPolicy\r
+ )\r
+{\r
+ EFI_STATUS Status;\r
+ EFI_MM_COMMUNICATE_HEADER *CommHeader;\r
+ VAR_CHECK_POLICY_COMM_HEADER *PolicyHeader;\r
+ VOID *PolicyBuffer;\r
+ UINTN BufferSize;\r
+ UINTN RequiredSize;\r
+\r
+ if (NewPolicy == NULL) {\r
+ return EFI_INVALID_PARAMETER;\r
+ }\r
+\r
+ // First, make sure that the required size does not exceed the capabilities\r
+ // of the MmCommunication buffer.\r
+ RequiredSize = OFFSET_OF(EFI_MM_COMMUNICATE_HEADER, Data) + sizeof(VAR_CHECK_POLICY_COMM_HEADER);\r
+ Status = SafeUintnAdd( RequiredSize, NewPolicy->Size, &RequiredSize );\r
+ if (EFI_ERROR( Status ) || RequiredSize > mMmCommunicationBufferSize) {\r
+ DEBUG(( DEBUG_ERROR, "%a - Policy too large for buffer! %r, %d > %d \n", __FUNCTION__,\r
+ Status, RequiredSize, mMmCommunicationBufferSize ));\r
+ return EFI_OUT_OF_RESOURCES;\r
+ }\r
+\r
+ AcquireLockOnlyAtBootTime (&mMmCommunicationLock);\r
+\r
+ // Set up the MM communication.\r
+ BufferSize = mMmCommunicationBufferSize;\r
+ CommHeader = mMmCommunicationBuffer;\r
+ PolicyHeader = (VAR_CHECK_POLICY_COMM_HEADER*)&CommHeader->Data;\r
+ PolicyBuffer = (VOID*)(PolicyHeader + 1);\r
+ CopyGuid( &CommHeader->HeaderGuid, &gVarCheckPolicyLibMmiHandlerGuid );\r
+ CommHeader->MessageLength = BufferSize;\r
+ PolicyHeader->Signature = VAR_CHECK_POLICY_COMM_SIG;\r
+ PolicyHeader->Revision = VAR_CHECK_POLICY_COMM_REVISION;\r
+ PolicyHeader->Command = VAR_CHECK_POLICY_COMMAND_REGISTER;\r
+\r
+ // Copy the policy into place. This copy is safe because we've already tested above.\r
+ CopyMem( PolicyBuffer, NewPolicy, NewPolicy->Size );\r
+\r
+ Status = InternalMmCommunicate (CommHeader, &BufferSize);\r
+ DEBUG(( DEBUG_VERBOSE, "%a - MmCommunication returned %r.\n", __FUNCTION__, Status ));\r
+\r
+ ReleaseLockOnlyAtBootTime (&mMmCommunicationLock);\r
+\r
+ return (EFI_ERROR( Status )) ? Status : PolicyHeader->Result;\r
+}\r
+\r
+\r
+/**\r
+ This helper function takes care of the overhead of formatting, sending, and interpreting\r
+ the results for a single DumpVariablePolicy request.\r
+\r
+ @param[in] PageRequested The page of the paginated results from MM. 0 for metadata.\r
+ @param[out] TotalSize The total size of the entire buffer. Returned as part of metadata.\r
+ @param[out] PageSize The size of the current page being returned. Not valid as part of metadata.\r
+ @param[out] HasMore A flag indicating whether there are more pages after this one.\r
+ @param[out] Buffer The start of the current page from MM.\r
+\r
+ @retval EFI_SUCCESS Output params have been updated (either metadata or dump page).\r
+ @retval EFI_INVALID_PARAMETER One of the output params is NULL.\r
+ @retval Others Response from MM handler.\r
+\r
+**/\r
+STATIC\r
+EFI_STATUS\r
+DumpVariablePolicyHelper (\r
+ IN UINT32 PageRequested,\r
+ OUT UINT32 *TotalSize,\r
+ OUT UINT32 *PageSize,\r
+ OUT BOOLEAN *HasMore,\r
+ OUT UINT8 **Buffer\r
+ )\r
+{\r
+ EFI_STATUS Status;\r
+ EFI_MM_COMMUNICATE_HEADER *CommHeader;\r
+ VAR_CHECK_POLICY_COMM_HEADER *PolicyHeader;\r
+ VAR_CHECK_POLICY_COMM_DUMP_PARAMS *CommandParams;\r
+ UINTN BufferSize;\r
+\r
+ if (TotalSize == NULL || PageSize == NULL || HasMore == NULL || Buffer == NULL) {\r
+ return EFI_INVALID_PARAMETER;\r
+ }\r
+\r
+ // Set up the MM communication.\r
+ BufferSize = mMmCommunicationBufferSize;\r
+ CommHeader = mMmCommunicationBuffer;\r
+ PolicyHeader = (VAR_CHECK_POLICY_COMM_HEADER*)&CommHeader->Data;\r
+ CommandParams = (VAR_CHECK_POLICY_COMM_DUMP_PARAMS*)(PolicyHeader + 1);\r
+ CopyGuid( &CommHeader->HeaderGuid, &gVarCheckPolicyLibMmiHandlerGuid );\r
+ CommHeader->MessageLength = BufferSize;\r
+ PolicyHeader->Signature = VAR_CHECK_POLICY_COMM_SIG;\r
+ PolicyHeader->Revision = VAR_CHECK_POLICY_COMM_REVISION;\r
+ PolicyHeader->Command = VAR_CHECK_POLICY_COMMAND_DUMP;\r
+\r
+ CommandParams->PageRequested = PageRequested;\r
+\r
+ Status = InternalMmCommunicate (CommHeader, &BufferSize);\r
+ DEBUG(( DEBUG_VERBOSE, "%a - MmCommunication returned %r.\n", __FUNCTION__, Status ));\r
+\r
+ if (!EFI_ERROR( Status )) {\r
+ Status = PolicyHeader->Result;\r
+ *TotalSize = CommandParams->TotalSize;\r
+ *PageSize = CommandParams->PageSize;\r
+ *HasMore = CommandParams->HasMore;\r
+ *Buffer = (UINT8*)(CommandParams + 1);\r
+ }\r
+\r
+ return Status;\r
+}\r
+\r
+\r
+/**\r
+ This API function will dump the entire contents of the variable policy table.\r
+\r
+ Similar to GetVariable, the first call can be made with a 0 size and it will return\r
+ the size of the buffer required to hold the entire table.\r
+\r
+ @param[out] Policy Pointer to the policy buffer. Can be NULL if Size is 0.\r
+ @param[in,out] Size On input, the size of the output buffer. On output, the size\r
+ of the data returned.\r
+\r
+ @retval EFI_SUCCESS Policy data is in the output buffer and Size has been updated.\r
+ @retval EFI_INVALID_PARAMETER Size is NULL, or Size is non-zero and Policy is NULL.\r
+ @retval EFI_BUFFER_TOO_SMALL Size is insufficient to hold policy. Size updated with required size.\r
+\r
+**/\r
+STATIC\r
+EFI_STATUS\r
+EFIAPI\r
+ProtocolDumpVariablePolicy (\r
+ OUT UINT8 *Policy OPTIONAL,\r
+ IN OUT UINT32 *Size\r
+ )\r
+{\r
+ EFI_STATUS Status;\r
+ UINT8 *Source;\r
+ UINT8 *Destination;\r
+ UINT32 PolicySize;\r
+ UINT32 PageSize;\r
+ BOOLEAN HasMore;\r
+ UINT32 PageIndex;\r
+\r
+ if (Size == NULL || (*Size > 0 && Policy == NULL)) {\r
+ return EFI_INVALID_PARAMETER;\r
+ }\r
+\r
+ AcquireLockOnlyAtBootTime (&mMmCommunicationLock);\r
+\r
+ // Repeat this whole process until we either have a failure case or get the entire buffer.\r
+ do {\r
+ // First, we must check the zero page to determine the buffer size and\r
+ // reset the internal state.\r
+ PolicySize = 0;\r
+ PageSize = 0;\r
+ HasMore = FALSE;\r
+ Status = DumpVariablePolicyHelper (0, &PolicySize, &PageSize, &HasMore, &Source);\r
+ if (EFI_ERROR (Status)) {\r
+ break;\r
+ }\r
+\r
+ // If we're good, we can at least check the required size now.\r
+ if (*Size < PolicySize) {\r
+ *Size = PolicySize;\r
+ Status = EFI_BUFFER_TOO_SMALL;\r
+ break;\r
+ }\r
+\r
+ // On further thought, let's update the size either way.\r
+ *Size = PolicySize;\r
+ // And get ready to ROCK.\r
+ Destination = Policy;\r
+\r
+ // Keep looping and copying until we're either done or freak out.\r
+ for (PageIndex = 1; !EFI_ERROR (Status) && HasMore && PageIndex < MAX_UINT32; PageIndex++) {\r
+ Status = DumpVariablePolicyHelper (PageIndex, &PolicySize, &PageSize, &HasMore, &Source);\r
+ if (!EFI_ERROR (Status)) {\r
+ CopyMem (Destination, Source, PageSize);\r
+ Destination += PageSize;\r
+ }\r
+ }\r
+\r
+ // Next, we check to see whether\r
+ } while (Status == EFI_TIMEOUT);\r
+\r
+ ReleaseLockOnlyAtBootTime (&mMmCommunicationLock);\r
+\r
+ // There's currently no use for this, but it shouldn't be hard to implement.\r
+ return Status;\r
+}\r
+\r
+\r
+/**\r
+ This API function locks the interface so that no more policy updates\r
+ can be performed or changes made to the enforcement until the next boot.\r
+\r
+ @retval EFI_SUCCESS\r
+ @retval Others An error has prevented this command from completing.\r
+\r
+**/\r
+STATIC\r
+EFI_STATUS\r
+EFIAPI\r
+ProtocolLockVariablePolicy (\r
+ VOID\r
+ )\r
+{\r
+ EFI_STATUS Status;\r
+ EFI_MM_COMMUNICATE_HEADER *CommHeader;\r
+ VAR_CHECK_POLICY_COMM_HEADER *PolicyHeader;\r
+ UINTN BufferSize;\r
+\r
+ AcquireLockOnlyAtBootTime (&mMmCommunicationLock);\r
+\r
+ // Set up the MM communication.\r
+ BufferSize = mMmCommunicationBufferSize;\r
+ CommHeader = mMmCommunicationBuffer;\r
+ PolicyHeader = (VAR_CHECK_POLICY_COMM_HEADER*)&CommHeader->Data;\r
+ CopyGuid( &CommHeader->HeaderGuid, &gVarCheckPolicyLibMmiHandlerGuid );\r
+ CommHeader->MessageLength = BufferSize;\r
+ PolicyHeader->Signature = VAR_CHECK_POLICY_COMM_SIG;\r
+ PolicyHeader->Revision = VAR_CHECK_POLICY_COMM_REVISION;\r
+ PolicyHeader->Command = VAR_CHECK_POLICY_COMMAND_LOCK;\r
+\r
+ Status = InternalMmCommunicate (CommHeader, &BufferSize);\r
+ DEBUG(( DEBUG_VERBOSE, "%a - MmCommunication returned %r.\n", __FUNCTION__, Status ));\r
+\r
+ ReleaseLockOnlyAtBootTime (&mMmCommunicationLock);\r
+\r
+ return (EFI_ERROR( Status )) ? Status : PolicyHeader->Result;\r
+}\r
+\r
+\r
+/**\r
+ This helper function locates the shared comm buffer and assigns it to input pointers.\r
+\r
+ @param[in,out] BufferSize On input, the minimum buffer size required INCLUDING the MM communicate header.\r
+ On output, the size of the matching buffer found.\r
+ @param[out] LocatedBuffer A pointer to the matching buffer.\r
+\r
+ @retval EFI_SUCCESS\r
+ @retval EFI_INVALID_PARAMETER One of the output pointers was NULL.\r
+ @retval EFI_OUT_OF_RESOURCES Not enough memory to allocate a comm buffer.\r
+\r
+**/\r
+STATIC\r
+EFI_STATUS\r
+InitMmCommonCommBuffer (\r
+ IN OUT UINTN *BufferSize,\r
+ OUT VOID **LocatedBuffer\r
+ )\r
+{\r
+ EFI_STATUS Status;\r
+\r
+ Status = EFI_SUCCESS;\r
+\r
+ // Make sure that we're working with good pointers.\r
+ if (BufferSize == NULL || LocatedBuffer == NULL) {\r
+ return EFI_INVALID_PARAMETER;\r
+ }\r
+\r
+ // Allocate the runtime memory for the comm buffer.\r
+ *LocatedBuffer = AllocateRuntimePool (*BufferSize);\r
+ if (*LocatedBuffer == NULL) {\r
+ Status = EFI_OUT_OF_RESOURCES;\r
+ *BufferSize = 0;\r
+ }\r
+\r
+ EfiInitializeLock (&mMmCommunicationLock, TPL_NOTIFY);\r
+\r
+ return Status;\r
+}\r
+\r
+\r
+/**\r
+ Convert internal pointer addresses to virtual addresses.\r
+\r
+ @param[in] Event Event whose notification function is being invoked.\r
+ @param[in] Context The pointer to the notification function's context, which\r
+ is implementation-dependent.\r
+**/\r
+STATIC\r
+VOID\r
+EFIAPI\r
+VariablePolicyVirtualAddressCallback (\r
+ IN EFI_EVENT Event,\r
+ IN VOID *Context\r
+ )\r
+{\r
+ EfiConvertPointer (0, (VOID **)&mMmCommunication);\r
+ EfiConvertPointer (0, (VOID **)&mMmCommunicationBuffer);\r
+}\r
+\r
+\r
+/**\r
+ The driver's entry point.\r
+\r
+ @param[in] ImageHandle The firmware allocated handle for the EFI image.\r
+ @param[in] SystemTable A pointer to the EFI System Table.\r
+\r
+ @retval EFI_SUCCESS The entry point executed successfully.\r
+ @retval other Some error occured when executing this entry point.\r
+\r
+**/\r
+EFI_STATUS\r
+EFIAPI\r
+VariablePolicySmmDxeMain (\r
+ IN EFI_HANDLE ImageHandle,\r
+ IN EFI_SYSTEM_TABLE *SystemTable\r
+ )\r
+{\r
+ EFI_STATUS Status;\r
+ BOOLEAN ProtocolInstalled;\r
+ BOOLEAN VirtualAddressChangeRegistered;\r
+ EFI_EVENT VirtualAddressChangeEvent;\r
+\r
+ Status = EFI_SUCCESS;\r
+ ProtocolInstalled = FALSE;\r
+ VirtualAddressChangeRegistered = FALSE;\r
+\r
+ // Update the minimum buffer size.\r
+ mMmCommunicationBufferSize = VAR_CHECK_POLICY_MM_COMM_BUFFER_SIZE;\r
+ // Locate the shared comm buffer to use for sending MM commands.\r
+ Status = InitMmCommonCommBuffer( &mMmCommunicationBufferSize, &mMmCommunicationBuffer );\r
+ if (EFI_ERROR( Status )) {\r
+ DEBUG((DEBUG_ERROR, "%a - Failed to locate a viable MM comm buffer! %r\n", __FUNCTION__, Status));\r
+ ASSERT_EFI_ERROR( Status );\r
+ return Status;\r
+ }\r
+\r
+ // Locate the MmCommunication protocol.\r
+ Status = gBS->LocateProtocol( &gEfiMmCommunication2ProtocolGuid, NULL, (VOID**)&mMmCommunication );\r
+ if (EFI_ERROR( Status )) {\r
+ DEBUG((DEBUG_ERROR, "%a - Failed to locate MmCommunication protocol! %r\n", __FUNCTION__, Status));\r
+ ASSERT_EFI_ERROR( Status );\r
+ return Status;\r
+ }\r
+\r
+ // Configure the VariablePolicy protocol structure.\r
+ mVariablePolicyProtocol.Revision = EDKII_VARIABLE_POLICY_PROTOCOL_REVISION;\r
+ mVariablePolicyProtocol.DisableVariablePolicy = ProtocolDisableVariablePolicy;\r
+ mVariablePolicyProtocol.IsVariablePolicyEnabled = ProtocolIsVariablePolicyEnabled;\r
+ mVariablePolicyProtocol.RegisterVariablePolicy = ProtocolRegisterVariablePolicy;\r
+ mVariablePolicyProtocol.DumpVariablePolicy = ProtocolDumpVariablePolicy;\r
+ mVariablePolicyProtocol.LockVariablePolicy = ProtocolLockVariablePolicy;\r
+\r
+ // Register all the protocols and return the status.\r
+ Status = gBS->InstallMultipleProtocolInterfaces( &ImageHandle,\r
+ &gEdkiiVariablePolicyProtocolGuid, &mVariablePolicyProtocol,\r
+ NULL );\r
+ if (EFI_ERROR( Status )) {\r
+ DEBUG(( DEBUG_ERROR, "%a - Failed to install protocol! %r\n", __FUNCTION__, Status ));\r
+ goto Exit;\r
+ }\r
+ else {\r
+ ProtocolInstalled = TRUE;\r
+ }\r
+\r
+ // Normally, we might want to register a callback\r
+ // to lock the interface, but this is integrated\r
+ // into the existing callbacks in VaraiableSmm.c\r
+ // and VariableDxe.c.\r
+\r
+ //\r
+ // Register a VirtualAddressChange callback for the MmComm protocol and Comm buffer.\r
+ Status = gBS->CreateEventEx (EVT_NOTIFY_SIGNAL,\r
+ TPL_NOTIFY,\r
+ VariablePolicyVirtualAddressCallback,\r
+ NULL,\r
+ &gEfiEventVirtualAddressChangeGuid,\r
+ &VirtualAddressChangeEvent);\r
+ if (EFI_ERROR( Status )) {\r
+ DEBUG(( DEBUG_ERROR, "%a - Failed to create VirtualAddressChange event! %r\n", __FUNCTION__, Status ));\r
+ goto Exit;\r
+ }\r
+ else {\r
+ VirtualAddressChangeRegistered = TRUE;\r
+ }\r
+\r
+\r
+Exit:\r
+ //\r
+ // If we're about to return a failed status (and unload this driver), we must first undo anything that\r
+ // has been successfully done.\r
+ if (EFI_ERROR( Status )) {\r
+ if (ProtocolInstalled) {\r
+ gBS->UninstallProtocolInterface( &ImageHandle, &gEdkiiVariablePolicyProtocolGuid, &mVariablePolicyProtocol );\r
+ }\r
+ if (VirtualAddressChangeRegistered) {\r
+ gBS->CloseEvent( VirtualAddressChangeEvent );\r
+ }\r
+ }\r
+\r
+ return Status;\r
+}\r
projects / mirror_edk2.git / blobdiff