///\r
/// Define a memory cache that improves the search performance for a variable.\r
///\r
-VARIABLE_STORE_HEADER *mNvVariableCache = NULL;\r
+VARIABLE_STORE_HEADER *mNvVariableCache = NULL;\r
\r
///\r
/// The memory entry used for variable statistics data.\r
///\r
-VARIABLE_INFO_ENTRY *gVariableInfo = NULL;\r
+VARIABLE_INFO_ENTRY *gVariableInfo = NULL;\r
+\r
+///\r
+/// The list to store the variables which cannot be set after the EFI_END_OF_DXE_EVENT_GROUP_GUID\r
+/// or EVT_GROUP_READY_TO_BOOT event.\r
+///\r
+LIST_ENTRY mLockedVariableList = INITIALIZE_LIST_HEAD_VARIABLE (mLockedVariableList);\r
+\r
+///\r
+/// The flag to indicate whether the platform has left the DXE phase of execution.\r
+///\r
+BOOLEAN mEndOfDxe = FALSE;\r
+\r
+///\r
+/// The flag to indicate whether the variable storage locking is enabled.\r
+///\r
+BOOLEAN mEnableLocking = TRUE;\r
\r
\r
/**\r
return TRUE;\r
}\r
\r
+/**\r
+ Mark a variable that will become read-only after leaving the DXE phase of execution.\r
+\r
+ @param[in] This The VARIABLE_LOCK_PROTOCOL instance.\r
+ @param[in] VariableName A pointer to the variable name that will be made read-only subsequently.\r
+ @param[in] VendorGuid A pointer to the vendor GUID that will be made read-only subsequently.\r
+\r
+ @retval EFI_SUCCESS The variable specified by the VariableName and the VendorGuid was marked\r
+ as pending to be read-only.\r
+ @retval EFI_INVALID_PARAMETER VariableName or VendorGuid is NULL.\r
+ Or VariableName is an empty string.\r
+ @retval EFI_ACCESS_DENIED EFI_END_OF_DXE_EVENT_GROUP_GUID or EFI_EVENT_GROUP_READY_TO_BOOT has\r
+ already been signaled.\r
+ @retval EFI_OUT_OF_RESOURCES There is not enough resource to hold the lock request.\r
+**/\r
+EFI_STATUS\r
+EFIAPI\r
+VariableLockRequestToLock (\r
+ IN CONST EDKII_VARIABLE_LOCK_PROTOCOL *This,\r
+ IN CHAR16 *VariableName,\r
+ IN EFI_GUID *VendorGuid\r
+ )\r
+{\r
+ VARIABLE_ENTRY *Entry;\r
+\r
+ if (VariableName == NULL || VariableName[0] == 0 || VendorGuid == NULL) {\r
+ return EFI_INVALID_PARAMETER;\r
+ }\r
+\r
+ if (mEndOfDxe) {\r
+ return EFI_ACCESS_DENIED;\r
+ }\r
+\r
+ Entry = AllocateRuntimePool (sizeof (*Entry) + StrSize (VariableName));\r
+ if (Entry == NULL) {\r
+ return EFI_OUT_OF_RESOURCES;\r
+ }\r
+\r
+ DEBUG ((EFI_D_INFO, "[Variable] Lock: %g:%s\n", VendorGuid, VariableName));\r
+\r
+ AcquireLockOnlyAtBootTime(&mVariableModuleGlobal->VariableGlobal.VariableServicesLock);\r
+\r
+ Entry->Name = (CHAR16 *) (Entry + 1);\r
+ StrCpy (Entry->Name, VariableName);\r
+ CopyGuid (&Entry->Guid, VendorGuid);\r
+ InsertTailList (&mLockedVariableList, &Entry->Link);\r
+\r
+ ReleaseLockOnlyAtBootTime (&mVariableModuleGlobal->VariableGlobal.VariableServicesLock);\r
+\r
+ return EFI_SUCCESS;\r
+}\r
+\r
/**\r
\r
This code finds variable in storage blocks (Volatile or Non-Volatile).\r
EFI_STATUS Status;\r
VARIABLE_HEADER *NextVariable;\r
EFI_PHYSICAL_ADDRESS Point;\r
+ LIST_ENTRY *Link;\r
+ VARIABLE_ENTRY *Entry;\r
\r
//\r
// Check input parameters.\r
} \r
}\r
\r
- if (AtRuntime ()) {\r
- //\r
- // HwErrRecSupport Global Variable identifies the level of hardware error record persistence\r
- // support implemented by the platform. This variable is only modified by firmware and is read-only to the OS.\r
- //\r
- if (CompareGuid (VendorGuid, &gEfiGlobalVariableGuid) && (StrCmp (VariableName, L"HwErrRecSupport") == 0)) {\r
- return EFI_WRITE_PROTECTED;\r
- }\r
- }\r
-\r
AcquireLockOnlyAtBootTime(&mVariableModuleGlobal->VariableGlobal.VariableServicesLock);\r
\r
//\r
mVariableModuleGlobal->NonVolatileLastVariableOffset = (UINTN) NextVariable - (UINTN) Point;\r
}\r
\r
+ if (mEndOfDxe && mEnableLocking) {\r
+ //\r
+ // Treat the variables listed in the forbidden variable list as read-only after leaving DXE phase.\r
+ //\r
+ for ( Link = GetFirstNode (&mLockedVariableList)\r
+ ; !IsNull (&mLockedVariableList, Link)\r
+ ; Link = GetNextNode (&mLockedVariableList, Link)\r
+ ) {\r
+ Entry = BASE_CR (Link, VARIABLE_ENTRY, Link);\r
+ if (CompareGuid (&Entry->Guid, VendorGuid) && (StrCmp (Entry->Name, VariableName) == 0)) {\r
+ Status = EFI_WRITE_PROTECTED;\r
+ DEBUG ((EFI_D_INFO, "[Variable]: Changing readonly variable after leaving DXE phase - %g:%s\n", VendorGuid, VariableName));\r
+ goto Done;\r
+ }\r
+ }\r
+ }\r
+\r
//\r
// Check whether the input variable is already existed.\r
//\r
Status = FindVariable (VariableName, VendorGuid, &Variable, &mVariableModuleGlobal->VariableGlobal, TRUE);\r
if (!EFI_ERROR (Status)) {\r
if (((Variable.CurrPtr->Attributes & EFI_VARIABLE_RUNTIME_ACCESS) == 0) && AtRuntime ()) {\r
- return EFI_WRITE_PROTECTED;\r
+ Status = EFI_WRITE_PROTECTED;\r
+ goto Done;\r
}\r
}\r
\r
\r
Status = UpdateVariable (VariableName, VendorGuid, Data, DataSize, Attributes, &Variable);\r
\r
+Done:\r
InterlockedDecrement (&mVariableModuleGlobal->VariableGlobal.ReentrantState);\r
ReleaseLockOnlyAtBootTime (&mVariableModuleGlobal->VariableGlobal.VariableServicesLock);\r
\r