diff options
Diffstat (limited to 'SecurityPkg/Tcg/MemoryOverwriteRequestControlLock/TcgMorLock.c')
| -rw-r--r-- | SecurityPkg/Tcg/MemoryOverwriteRequestControlLock/TcgMorLock.c | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/SecurityPkg/Tcg/MemoryOverwriteRequestControlLock/TcgMorLock.c b/SecurityPkg/Tcg/MemoryOverwriteRequestControlLock/TcgMorLock.c new file mode 100644 index 0000000000..7ca707915e --- /dev/null +++ b/SecurityPkg/Tcg/MemoryOverwriteRequestControlLock/TcgMorLock.c @@ -0,0 +1,196 @@ +/** @file
+ TCG MOR (Memory Overwrite Request) Lock Control Driver.
+
+ This driver initilize MemoryOverwriteRequestControlLock variable.
+ This module will add Variable Hook and allow MemoryOverwriteRequestControlLock variable set only once.
+
+Copyright (c) 2015, 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 <PiDxe.h>
+#include <Guid/MemoryOverwriteControl.h>
+#include <IndustryStandard/MemoryOverwriteRequestControlLock.h>
+#include <Library/DebugLib.h>
+#include <Library/BaseLib.h>
+#include <Library/BaseMemoryLib.h>
+#include "TcgMorLock.h"
+
+typedef struct {
+ CHAR16 *VariableName;
+ EFI_GUID *VendorGuid;
+} VARIABLE_TYPE;
+
+VARIABLE_TYPE mMorVariableType[] = {
+ {MEMORY_OVERWRITE_REQUEST_VARIABLE_NAME, &gEfiMemoryOverwriteControlDataGuid},
+ {MEMORY_OVERWRITE_REQUEST_CONTROL_LOCK_NAME, &gEfiMemoryOverwriteRequestControlLockGuid},
+};
+
+/**
+ Returns if this is MOR related variable.
+
+ @param VariableName the name of the vendor's variable, it's a Null-Terminated Unicode String
+ @param VendorGuid Unify identifier for vendor.
+
+ @retval TRUE The variable is MOR related.
+ @retval FALSE The variable is NOT MOR related.
+**/
+BOOLEAN
+IsAnyMorVariable (
+ IN CHAR16 *VariableName,
+ IN EFI_GUID *VendorGuid
+ )
+{
+ UINTN Index;
+
+ for (Index = 0; Index < sizeof(mMorVariableType)/sizeof(mMorVariableType[0]); Index++) {
+ if ((StrCmp (VariableName, mMorVariableType[Index].VariableName) == 0) &&
+ (CompareGuid (VendorGuid, mMorVariableType[Index].VendorGuid))) {
+ return TRUE;
+ }
+ }
+ return FALSE;
+}
+
+/**
+ Returns if this is MOR lock variable.
+
+ @param VariableName the name of the vendor's variable, it's a Null-Terminated Unicode String
+ @param VendorGuid Unify identifier for vendor.
+
+ @retval TRUE The variable is MOR lock variable.
+ @retval FALSE The variable is NOT MOR lock variable.
+**/
+BOOLEAN
+IsMorLockVariable (
+ IN CHAR16 *VariableName,
+ IN EFI_GUID *VendorGuid
+ )
+{
+ if ((StrCmp (VariableName, MEMORY_OVERWRITE_REQUEST_CONTROL_LOCK_NAME) == 0) &&
+ (CompareGuid (VendorGuid, &gEfiMemoryOverwriteRequestControlLockGuid))) {
+ return TRUE;
+ }
+ return FALSE;
+}
+
+/**
+ This service is a checker handler for the UEFI Runtime Service SetVariable()
+
+ @param VariableName the name of the vendor's variable, as a
+ Null-Terminated Unicode String
+ @param VendorGuid Unify identifier for vendor.
+ @param Attributes Point to memory location to return the attributes of variable. If the point
+ is NULL, the parameter would be ignored.
+ @param DataSize The size in bytes of Data-Buffer.
+ @param Data Point to the content of the variable.
+
+ @retval EFI_SUCCESS The firmware has successfully stored the variable and its data as
+ defined by the Attributes.
+ @retval EFI_INVALID_PARAMETER An invalid combination of attribute bits was supplied, or the
+ DataSize exceeds the maximum allowed.
+ @retval EFI_INVALID_PARAMETER VariableName is an empty Unicode string.
+ @retval EFI_OUT_OF_RESOURCES Not enough storage is available to hold the variable and its data.
+ @retval EFI_DEVICE_ERROR The variable could not be saved due to a hardware failure.
+ @retval EFI_WRITE_PROTECTED The variable in question is read-only.
+ @retval EFI_WRITE_PROTECTED The variable in question cannot be deleted.
+ @retval EFI_SECURITY_VIOLATION The variable could not be written due to EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS
+ set but the AuthInfo does NOT pass the validation check carried
+ out by the firmware.
+ @retval EFI_NOT_FOUND The variable trying to be updated or deleted was not found.
+
+**/
+EFI_STATUS
+EFIAPI
+SetVariableCheckHandlerMor (
+ IN CHAR16 *VariableName,
+ IN EFI_GUID *VendorGuid,
+ IN UINT32 Attributes,
+ IN UINTN DataSize,
+ IN VOID *Data
+ )
+{
+ UINTN MorLockDataSize;
+ BOOLEAN MorLock;
+ EFI_STATUS Status;
+
+ //
+ // do not handle non-MOR variable
+ //
+ if (!IsAnyMorVariable (VariableName, VendorGuid)) {
+ return EFI_SUCCESS;
+ }
+
+ MorLockDataSize = sizeof(MorLock);
+ Status = InternalGetVariable (
+ MEMORY_OVERWRITE_REQUEST_CONTROL_LOCK_NAME,
+ &gEfiMemoryOverwriteRequestControlLockGuid,
+ NULL,
+ &MorLockDataSize,
+ &MorLock
+ );
+ if (!EFI_ERROR (Status) && MorLock) {
+ //
+ // If lock, deny access
+ //
+ return EFI_INVALID_PARAMETER;
+ }
+
+ //
+ // check format
+ //
+ if (IsMorLockVariable(VariableName, VendorGuid)) {
+ //
+ // Delete not OK
+ //
+ if ((DataSize == 0) || (Data == NULL) || (Attributes == 0)) {
+ return EFI_INVALID_PARAMETER;
+ }
+ //
+ // set to any other value not OK
+ //
+ if ((DataSize != sizeof(UINT8)) || ((*(UINT8 *)Data != 1) && (*(UINT8 *)Data != 0))) {
+ return EFI_INVALID_PARAMETER;
+ }
+ }
+ //
+ // Or grant access
+ //
+ return EFI_SUCCESS;
+}
+
+/**
+ Entry Point for MOR Lock Control driver.
+
+ @param[in] ImageHandle Image handle of this driver.
+ @param[in] SystemTable A Pointer to the EFI System Table.
+
+ @retval EFI_SUCEESS
+ @return Others Some error occurs.
+**/
+EFI_STATUS
+EFIAPI
+MorLockDriverInit (
+ VOID
+ )
+{
+ EFI_STATUS Status;
+ UINT8 Data;
+
+ Data = 0;
+ Status = InternalSetVariable (
+ MEMORY_OVERWRITE_REQUEST_CONTROL_LOCK_NAME,
+ &gEfiMemoryOverwriteRequestControlLockGuid,
+ EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS,
+ 1,
+ &Data
+ );
+ return Status;
+}
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