MdePkg/MdeModulePkg/SecurityPkg Variable: Forbid creation of non-spec variables in EFI_GLOBAL_VARIABLE namespace.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@14560 6f19259b-4bc3-4df7-8a09-765794883524

2 files changed, 128 insertions, 13 deletions

diff --git a/SecurityPkg/VariableAuthenticated/RuntimeDxe/Variable.c b/SecurityPkg/VariableAuthenticated/RuntimeDxe/Variable.c
index 53ef092af..5261157ff 100644
--- a/SecurityPkg/VariableAuthenticated/RuntimeDxe/Variable.c
+++ b/SecurityPkg/VariableAuthenticated/RuntimeDxe/Variable.c
@@ -58,6 +58,51 @@ BOOLEAN                mEndOfDxe              = FALSE;
 ///

 BOOLEAN                mEnableLocking         = TRUE;

 

+//

+// To prevent name collisions with possible future globally defined variables,

+// other internal firmware data variables that are not defined here must be

+// saved with a unique VendorGuid other than EFI_GLOBAL_VARIABLE or

+// any other GUID defined by the UEFI Specification. Implementations must

+// only permit the creation of variables with a UEFI Specification-defined

+// VendorGuid when these variables are documented in the UEFI Specification.

+//

+GLOBAL_VARIABLE_ENTRY mGlobalVariableList[] = {

+  {EFI_LANG_CODES_VARIABLE_NAME,             VARIABLE_ATTRIBUTE_BS_RT},

+  {EFI_LANG_VARIABLE_NAME,                   VARIABLE_ATTRIBUTE_NV_BS_RT},

+  {EFI_TIME_OUT_VARIABLE_NAME,               VARIABLE_ATTRIBUTE_NV_BS_RT},

+  {EFI_PLATFORM_LANG_CODES_VARIABLE_NAME,    VARIABLE_ATTRIBUTE_BS_RT},

+  {EFI_PLATFORM_LANG_VARIABLE_NAME,          VARIABLE_ATTRIBUTE_NV_BS_RT},

+  {EFI_CON_IN_VARIABLE_NAME,                 VARIABLE_ATTRIBUTE_NV_BS_RT},

+  {EFI_CON_OUT_VARIABLE_NAME,                VARIABLE_ATTRIBUTE_NV_BS_RT},

+  {EFI_ERR_OUT_VARIABLE_NAME,                VARIABLE_ATTRIBUTE_NV_BS_RT},

+  {EFI_CON_IN_DEV_VARIABLE_NAME,             VARIABLE_ATTRIBUTE_BS_RT},

+  {EFI_CON_OUT_DEV_VARIABLE_NAME,            VARIABLE_ATTRIBUTE_BS_RT},

+  {EFI_ERR_OUT_DEV_VARIABLE_NAME,            VARIABLE_ATTRIBUTE_BS_RT},

+  {EFI_BOOT_ORDER_VARIABLE_NAME,             VARIABLE_ATTRIBUTE_NV_BS_RT},

+  {EFI_BOOT_NEXT_VARIABLE_NAME,              VARIABLE_ATTRIBUTE_NV_BS_RT},

+  {EFI_BOOT_CURRENT_VARIABLE_NAME,           VARIABLE_ATTRIBUTE_BS_RT},

+  {EFI_BOOT_OPTION_SUPPORT_VARIABLE_NAME,    VARIABLE_ATTRIBUTE_BS_RT},

+  {EFI_DRIVER_ORDER_VARIABLE_NAME,           VARIABLE_ATTRIBUTE_NV_BS_RT},

+  {EFI_HW_ERR_REC_SUPPORT_VARIABLE_NAME,     VARIABLE_ATTRIBUTE_NV_BS_RT},

+  {EFI_SETUP_MODE_NAME,                      VARIABLE_ATTRIBUTE_BS_RT},

+  {EFI_KEY_EXCHANGE_KEY_NAME,                VARIABLE_ATTRIBUTE_NV_BS_RT_AT},

+  {EFI_PLATFORM_KEY_NAME,                    VARIABLE_ATTRIBUTE_NV_BS_RT_AT},

+  {EFI_SIGNATURE_SUPPORT_NAME,               VARIABLE_ATTRIBUTE_BS_RT},

+  {EFI_SECURE_BOOT_MODE_NAME,                VARIABLE_ATTRIBUTE_BS_RT},

+  {EFI_KEK_DEFAULT_VARIABLE_NAME,            VARIABLE_ATTRIBUTE_BS_RT},

+  {EFI_PK_DEFAULT_VARIABLE_NAME,             VARIABLE_ATTRIBUTE_BS_RT},

+  {EFI_DB_DEFAULT_VARIABLE_NAME,             VARIABLE_ATTRIBUTE_BS_RT},

+  {EFI_DBX_DEFAULT_VARIABLE_NAME,            VARIABLE_ATTRIBUTE_BS_RT},

+  {EFI_DBT_DEFAULT_VARIABLE_NAME,            VARIABLE_ATTRIBUTE_BS_RT},

+  {EFI_OS_INDICATIONS_SUPPORT_VARIABLE_NAME, VARIABLE_ATTRIBUTE_BS_RT},

+  {EFI_OS_INDICATIONS_VARIABLE_NAME,         VARIABLE_ATTRIBUTE_NV_BS_RT},

+  {EFI_VENDOR_KEYS_VARIABLE_NAME,            VARIABLE_ATTRIBUTE_BS_RT},

+};

+GLOBAL_VARIABLE_ENTRY mGlobalVariableList2[] = {

+  {L"Boot####",                              VARIABLE_ATTRIBUTE_NV_BS_RT},

+  {L"Driver####",                            VARIABLE_ATTRIBUTE_NV_BS_RT},

+  {L"Key####",                               VARIABLE_ATTRIBUTE_NV_BS_RT},

+};

 

 /**

   Routine used to track statistical information about variable usage.

@@ -1473,7 +1518,7 @@ AutoUpdateLangVariable (
 

   SetLanguageCodes = FALSE;

 

-  if (StrCmp (VariableName, L"PlatformLangCodes") == 0) {

+  if (StrCmp (VariableName, EFI_PLATFORM_LANG_CODES_VARIABLE_NAME) == 0) {

     //

     // PlatformLangCodes is a volatile variable, so it can not be updated at runtime.

     //

@@ -1503,7 +1548,7 @@ AutoUpdateLangVariable (
     mVariableModuleGlobal->PlatformLang = AllocateRuntimePool (DataSize);

     ASSERT (mVariableModuleGlobal->PlatformLang != NULL);

 

-  } else if (StrCmp (VariableName, L"LangCodes") == 0) {

+  } else if (StrCmp (VariableName, EFI_LANG_CODES_VARIABLE_NAME) == 0) {

     //

     // LangCodes is a volatile variable, so it can not be updated at runtime.

     //

@@ -1531,21 +1576,21 @@ AutoUpdateLangVariable (
     // Update Lang if PlatformLang is already set

     // Update PlatformLang if Lang is already set

     //

-    Status = FindVariable (L"PlatformLang", &gEfiGlobalVariableGuid, &Variable, &mVariableModuleGlobal->VariableGlobal, FALSE);

+    Status = FindVariable (EFI_PLATFORM_LANG_VARIABLE_NAME, &gEfiGlobalVariableGuid, &Variable, &mVariableModuleGlobal->VariableGlobal, FALSE);

     if (!EFI_ERROR (Status)) {

       //

       // Update Lang

       //

-      VariableName = L"PlatformLang";

+      VariableName = EFI_PLATFORM_LANG_VARIABLE_NAME;

       Data         = GetVariableDataPtr (Variable.CurrPtr);

       DataSize     = Variable.CurrPtr->DataSize;

     } else {

-      Status = FindVariable (L"Lang", &gEfiGlobalVariableGuid, &Variable, &mVariableModuleGlobal->VariableGlobal, FALSE);

+      Status = FindVariable (EFI_LANG_VARIABLE_NAME, &gEfiGlobalVariableGuid, &Variable, &mVariableModuleGlobal->VariableGlobal, FALSE);

       if (!EFI_ERROR (Status)) {

         //

         // Update PlatformLang

         //

-        VariableName = L"Lang";

+        VariableName = EFI_LANG_VARIABLE_NAME;

         Data         = GetVariableDataPtr (Variable.CurrPtr);

         DataSize     = Variable.CurrPtr->DataSize;

       } else {

@@ -1562,7 +1607,7 @@ AutoUpdateLangVariable (
   //

   Attributes = EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS;

 

-  if (StrCmp (VariableName, L"PlatformLang") == 0) {

+  if (StrCmp (VariableName, EFI_PLATFORM_LANG_VARIABLE_NAME) == 0) {

     //

     // Update Lang when PlatformLangCodes/LangCodes were set.

     //

@@ -1585,9 +1630,9 @@ AutoUpdateLangVariable (
         //

         // Successfully convert PlatformLang to Lang, and set the BestLang value into Lang variable simultaneously.

         //

-        FindVariable (L"Lang", &gEfiGlobalVariableGuid, &Variable, &mVariableModuleGlobal->VariableGlobal, FALSE);

+        FindVariable (EFI_LANG_VARIABLE_NAME, &gEfiGlobalVariableGuid, &Variable, &mVariableModuleGlobal->VariableGlobal, FALSE);

 

-        Status = UpdateVariable (L"Lang", &gEfiGlobalVariableGuid, BestLang,

+        Status = UpdateVariable (EFI_LANG_VARIABLE_NAME, &gEfiGlobalVariableGuid, BestLang,

                                  ISO_639_2_ENTRY_SIZE + 1, Attributes, 0, 0, &Variable, NULL);

 

         DEBUG ((EFI_D_INFO, "Variable Driver Auto Update PlatformLang, PlatformLang:%a, Lang:%a\n", BestPlatformLang, BestLang));

@@ -1596,7 +1641,7 @@ AutoUpdateLangVariable (
       }

     }

 

-  } else if (StrCmp (VariableName, L"Lang") == 0) {

+  } else if (StrCmp (VariableName, EFI_LANG_VARIABLE_NAME) == 0) {

     //

     // Update PlatformLang when PlatformLangCodes/LangCodes were set.

     //

@@ -1619,9 +1664,9 @@ AutoUpdateLangVariable (
         //

         // Successfully convert Lang to PlatformLang, and set the BestPlatformLang value into PlatformLang variable simultaneously.

         //

-        FindVariable (L"PlatformLang", &gEfiGlobalVariableGuid, &Variable, &mVariableModuleGlobal->VariableGlobal, FALSE);

+        FindVariable (EFI_PLATFORM_LANG_VARIABLE_NAME, &gEfiGlobalVariableGuid, &Variable, &mVariableModuleGlobal->VariableGlobal, FALSE);

 

-        Status = UpdateVariable (L"PlatformLang", &gEfiGlobalVariableGuid, BestPlatformLang,

+        Status = UpdateVariable (EFI_PLATFORM_LANG_VARIABLE_NAME, &gEfiGlobalVariableGuid, BestPlatformLang,

                                  AsciiStrSize (BestPlatformLang), Attributes, 0, 0, &Variable, NULL);

 

         DEBUG ((EFI_D_INFO, "Variable Driver Auto Update Lang, Lang:%a, PlatformLang:%a\n", BestLang, BestPlatformLang));

@@ -2328,6 +2373,63 @@ IsHwErrRecVariable (
 }

 

 /**

+  This code checks if variable guid is global variable guid first.

+  If yes, further check if variable name is in mGlobalVariableList or mGlobalVariableList2 and attributes matched.

+

+  @param[in] VariableName       Pointer to variable name.

+  @param[in] VendorGuid         Variable Vendor Guid.

+  @param[in] Attributes         Attributes of the variable.

+

+  @retval EFI_SUCCESS           Variable is not global variable, or Variable is global variable, variable name is in the lists and attributes matched.

+  @retval EFI_INVALID_PARAMETER Variable is global variable, but variable name is not in the lists or attributes unmatched.

+

+**/

+EFI_STATUS

+EFIAPI

+CheckEfiGlobalVariable (

+  IN CHAR16             *VariableName,

+  IN EFI_GUID           *VendorGuid,

+  IN UINT32             Attributes

+  )

+{

+  UINTN     Index;

+  UINTN     NameLength;

+

+  if (CompareGuid (VendorGuid, &gEfiGlobalVariableGuid)){

+    //

+    // Try list 1, exactly match.

+    //

+    for (Index = 0; Index < sizeof (mGlobalVariableList)/sizeof (mGlobalVariableList[0]); Index++) {

+      if ((StrCmp (mGlobalVariableList[Index].Name, VariableName) == 0) &&

+          (Attributes == 0 || (Attributes & (~EFI_VARIABLE_APPEND_WRITE)) == mGlobalVariableList[Index].Attributes)) {

+        return EFI_SUCCESS;

+      }

+    }

+

+    //

+    // Try list 2.

+    //

+    NameLength = StrLen (VariableName) - 4;

+    for (Index = 0; Index < sizeof (mGlobalVariableList2)/sizeof (mGlobalVariableList2[0]); Index++) {

+      if ((StrLen (VariableName) == StrLen (mGlobalVariableList2[Index].Name)) &&

+          (StrnCmp (mGlobalVariableList2[Index].Name, VariableName, NameLength) == 0) &&

+          IsHexaDecimalDigitCharacter (VariableName[NameLength]) &&

+          IsHexaDecimalDigitCharacter (VariableName[NameLength + 1]) &&

+          IsHexaDecimalDigitCharacter (VariableName[NameLength + 2]) &&

+          IsHexaDecimalDigitCharacter (VariableName[NameLength + 3]) &&

+          (Attributes == 0 || (Attributes & (~EFI_VARIABLE_APPEND_WRITE)) == mGlobalVariableList2[Index].Attributes)) {

+        return EFI_SUCCESS;

+      }

+    }

+

+    DEBUG ((EFI_D_INFO, "[Variable]: set global variable with invalid variable name or attributes - %g:%s:%x\n", VendorGuid, VariableName, Attributes));

+    return EFI_INVALID_PARAMETER;

+  }

+

+  return EFI_SUCCESS;

+}

+

+/**

   Mark a variable that will become read-only after leaving the DXE phase of execution.

 

   @param[in] This          The VARIABLE_LOCK_PROTOCOL instance.

@@ -2787,6 +2889,11 @@ VariableServiceSetVariable (
     }

   }

 

+  Status = CheckEfiGlobalVariable (VariableName, VendorGuid, Attributes);

+  if (EFI_ERROR (Status)) {

+    return Status;

+  }

+

   AcquireLockOnlyAtBootTime(&mVariableModuleGlobal->VariableGlobal.VariableServicesLock);

 

   //

diff --git a/SecurityPkg/VariableAuthenticated/RuntimeDxe/Variable.h b/SecurityPkg/VariableAuthenticated/RuntimeDxe/Variable.h
index ebd0b50b1..9991dfe32 100644
--- a/SecurityPkg/VariableAuthenticated/RuntimeDxe/Variable.h
+++ b/SecurityPkg/VariableAuthenticated/RuntimeDxe/Variable.h
@@ -44,7 +44,6 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
 #include <Guid/FaultTolerantWrite.h>

 #include <Guid/HardwareErrorVariable.h>

 

-#define VARIABLE_RECLAIM_THRESHOLD (1024)

 #define EFI_VARIABLE_ATTRIBUTES_MASK (EFI_VARIABLE_NON_VOLATILE | \

                                       EFI_VARIABLE_BOOTSERVICE_ACCESS | \

                                       EFI_VARIABLE_RUNTIME_ACCESS | \

@@ -53,6 +52,15 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
                                       EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS | \

                                       EFI_VARIABLE_APPEND_WRITE)

 

+#define VARIABLE_ATTRIBUTE_BS_RT        (EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS)

+#define VARIABLE_ATTRIBUTE_NV_BS_RT     (VARIABLE_ATTRIBUTE_BS_RT | EFI_VARIABLE_NON_VOLATILE)

+#define VARIABLE_ATTRIBUTE_NV_BS_RT_AT  (VARIABLE_ATTRIBUTE_NV_BS_RT | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS)

+

+typedef struct {

+  CHAR16      *Name;

+  UINT32      Attributes;

+} GLOBAL_VARIABLE_ENTRY;

+

 ///

 /// The size of a 3 character ISO639 language code.

 ///