[mirror_edk2.git] / IntelFrameworkPkg / Library / FrameworkIfrSupportLib / IfrCommon.c

/** @file
  Common Library Routines to assist in IFR creation on-the-fly
  
Copyright (c) 2006, Intel Corporation
All rights reserved. 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 "IfrSupportLibInternal.h"

/**
  Determine what is the current language setting
  The setting is stored in language variable in flash. This routine
  will get setting by accesssing that variable. If failed to access
  language variable, then use default setting that 'eng' as current
  language setting.
  
  @param Lang Pointer of system language
  
  @return whether sucess to get setting from variable
**/
EFI_STATUS
GetCurrentLanguage (
  OUT     CHAR16              *Lang
  )
{
  EFI_STATUS  Status;
  UINTN       Size;
  UINTN       Index;
  CHAR8       Language[4];

  //
  // Getting the system language and placing it into our Global Data
  //
  Size = sizeof (Language);

  Status = gRT->GetVariable (
                  (CHAR16 *) L"Lang",
                  &gEfiGlobalVariableGuid,
                  NULL,
                  &Size,
                  Language
                  );

  if (EFI_ERROR (Status)) {
    AsciiStrCpy (Language, "eng");
  }

  for (Index = 0; Index < 3; Index++) {
    //
    // Bitwise AND ascii value with 0xDF yields an uppercase value.
    // Sign extend into a unicode value
    //
    Lang[Index] = (CHAR16) (Language[Index] & 0xDF);
  }

  //
  // Null-terminate the value
  //
  Lang[3] = (CHAR16) 0;

  return Status;
}

/**
  Add a string to the incoming buffer and return the token and offset data
  
  @param StringBuffer      The incoming buffer
  @param Language          Currrent language
  @param String            The string to be added
  @param StringToken       The index where the string placed  
  
  @retval EFI_OUT_OF_RESOURCES No enough buffer to allocate
  @retval EFI_SUCCESS          String successfully added to the incoming buffer
**/
EFI_STATUS
AddString (
  IN      VOID                *StringBuffer,
  IN      CHAR16              *Language,
  IN      CHAR16              *String,
  IN OUT  STRING_REF          *StringToken
  )
{
  EFI_HII_STRING_PACK *StringPack;
  EFI_HII_STRING_PACK *StringPackBuffer;
  VOID                *NewBuffer;
  RELOFST             *PackSource;
  RELOFST             *PackDestination;
  UINT8               *Source;
  UINT8               *Destination;
  UINTN               Index;
  BOOLEAN             Finished;
  UINTN               SizeofLanguage;
  UINTN               SizeofString;

  StringPack  = (EFI_HII_STRING_PACK *) StringBuffer;
  Finished    = FALSE;

  //
  // Pre-allocate a buffer sufficient for us to work on.
  // We will use it as a destination scratch pad to build data on
  // and when complete shift the data back to the original buffer
  //
  NewBuffer = AllocateZeroPool (DEFAULT_STRING_BUFFER_SIZE);
  if (NewBuffer == NULL) {
    return EFI_OUT_OF_RESOURCES;
  }

  StringPackBuffer = (EFI_HII_STRING_PACK *) NewBuffer;

  //
  // StringPack is terminated with a length 0 entry
  //
  for (; StringPack->Header.Length != 0;) {
    //
    // If this stringpack's language is same as CurrentLanguage, use it
    //
    if (CompareMem ((VOID *) ((CHAR8 *) (StringPack) + StringPack->LanguageNameString), Language, 3) == 0) {
      //
      // We have some data in this string pack, copy the string package up to the string data
      //
      CopyMem (&StringPackBuffer->Header, &StringPack->Header, sizeof (StringPack));

      //
      // These are references in the structure to tokens, need to increase them by the space occupied by an additional StringPointer
      //
      StringPackBuffer->LanguageNameString = (UINT16) (StringPackBuffer->LanguageNameString + (UINT16) sizeof (RELOFST));
      StringPackBuffer->PrintableLanguageName = (UINT16) (StringPackBuffer->PrintableLanguageName + (UINT16) sizeof (RELOFST));

      PackSource      = (RELOFST *) (StringPack + 1);
      PackDestination = (RELOFST *) (StringPackBuffer + 1);
      for (Index = 0; PackSource[Index] != 0x0000; Index++) {
        //
        // Copy the stringpointers from old to new buffer
        // remember that we are adding a string, so the string offsets will all go up by sizeof (RELOFST)
        //
        PackDestination[Index] = (UINT16) (PackDestination[Index] + sizeof (RELOFST));
      }

      //
      // Add a new stringpointer in the new buffer since we are adding a string.  Null terminate it
      //
      PackDestination[Index] = (UINT16)(PackDestination[Index-1] +
                                        StrSize((CHAR16 *)((CHAR8 *)(StringPack) + PackSource[Index-1])));
      PackDestination[Index + 1] = (UINT16) 0;

      //
      // Index is the token value for the new string
      //
      *StringToken = (UINT16) Index;

      //
      // Source now points to the beginning of the old buffer strings
      // Destination now points to the beginning of the new buffer strings
      //
      Source      = (UINT8 *) &PackSource[Index + 1];
      Destination = (UINT8 *) &PackDestination[Index + 2];

      //
      // This should copy all the strings from the old buffer to the new buffer
      //
      for (; Index != 0; Index--) {
        //
        // Copy Source string to destination buffer
        //
        StrCpy ((CHAR16 *) Destination, (CHAR16 *) Source);

        //
        // Adjust the source/destination to the next string location
        //
        Destination = Destination + StrSize ((CHAR16 *) Source);
        Source      = Source + StrSize ((CHAR16 *) Source);
      }

      //
      // This copies the new string to the destination buffer
      //
      StrCpy ((CHAR16 *) Destination, (CHAR16 *) String);

      //
      // Adjust the size of the changed string pack by adding the size of the new string
      // along with the size of the additional offset entry for the new string
      //
      StringPackBuffer->Header.Length = (UINT32) ((UINTN) StringPackBuffer->Header.Length + StrSize (String) + sizeof (RELOFST));

      //
      // Advance the buffers to point to the next spots.
      //
      StringPackBuffer  = (EFI_HII_STRING_PACK *) ((CHAR8 *) (StringPackBuffer) + StringPackBuffer->Header.Length);
      StringPack        = (EFI_HII_STRING_PACK *) ((CHAR8 *) (StringPack) + StringPack->Header.Length);
      Finished          = TRUE;
      continue;
    }
    //
    // This isn't the language of the stringpack we were asked to add a string to
    // so we need to copy it to the new buffer.
    //
    CopyMem (&StringPackBuffer->Header, &StringPack->Header, StringPack->Header.Length);

    //
    // Advance the buffers to point to the next spots.
    //
    StringPackBuffer  = (EFI_HII_STRING_PACK *) ((CHAR8 *) (StringPackBuffer) + StringPack->Header.Length);
    StringPack        = (EFI_HII_STRING_PACK *) ((CHAR8 *) (StringPack) + StringPack->Header.Length);
  }

  //
  // If we didn't copy the new data to a stringpack yet
  //
  if (!Finished) {
    PackDestination = (RELOFST *) (StringPackBuffer + 1);
    //
    // Pointing to a new string pack location
    //
    SizeofLanguage = StrSize (Language);
    SizeofString   = StrSize (String);
    StringPackBuffer->Header.Length = (UINT32)
      (
        sizeof (EFI_HII_STRING_PACK) -
        sizeof (EFI_STRING) +
        sizeof (RELOFST) +
        sizeof (RELOFST) +
        SizeofLanguage +
        SizeofString
      );
    StringPackBuffer->Header.Type           = EFI_HII_STRING;
    StringPackBuffer->LanguageNameString    = (UINT16) ((UINTN) &PackDestination[3] - (UINTN) StringPackBuffer);
    StringPackBuffer->PrintableLanguageName = (UINT16) ((UINTN) &PackDestination[3] - (UINTN) StringPackBuffer);
    StringPackBuffer->Attributes            = 0;
    PackDestination[0]                      = (UINT16) ((UINTN) &PackDestination[3] - (UINTN) StringPackBuffer);
    PackDestination[1]                      = (UINT16) (PackDestination[0] + StrSize (Language));
    PackDestination[2]                      = (UINT16) 0;

    //
    // The first string location will be set to destination.  The minimum number of strings
    // associated with a stringpack will always be token 0 stored as the languagename (e.g. ENG, SPA, etc)
    // and token 1 as the new string being added and and null entry for the stringpointers
    //
    Destination = (UINT8 *) &PackDestination[3];

    //
    // Copy the language name string to the new buffer
    //
    StrCpy ((CHAR16 *) Destination, Language);

    //
    // Advance the destination to the new empty spot
    //
    Destination = Destination + StrSize (Language);

    //
    // Copy the string to the new buffer
    //
    StrCpy ((CHAR16 *) Destination, String);

    //
    // Since we are starting with a new string pack - we know the new string is token 1
    //
    *StringToken = (UINT16) 1;
  }

  //
  // Zero out the original buffer and copy the updated data in the new buffer to the old buffer
  //
  ZeroMem (StringBuffer, DEFAULT_STRING_BUFFER_SIZE);
  CopyMem (StringBuffer, NewBuffer, DEFAULT_STRING_BUFFER_SIZE);

  //
  // Free the newly created buffer since we don't need it anymore
  //
  gBS->FreePool (NewBuffer);
  return EFI_SUCCESS;
}

/**
  Add op-code data to the FormBuffer
  
  @param FormBuffer      Form buffer to be inserted to
  @param OpCodeData      Op-code data to be inserted  
  
  @retval EFI_OUT_OF_RESOURCES    No enough buffer to allocate
  @retval EFI_SUCCESS             Op-code data successfully inserted  
**/
EFI_STATUS
AddOpCode (
  IN      VOID                *FormBuffer,
  IN OUT  VOID                *OpCodeData
  )
{
  EFI_HII_PACK_HEADER *NewBuffer;
  UINT8               *Source;
  UINT8               *Destination;

  //
  // Pre-allocate a buffer sufficient for us to work on.
  // We will use it as a destination scratch pad to build data on
  // and when complete shift the data back to the original buffer
  //
  NewBuffer = AllocateZeroPool (DEFAULT_FORM_BUFFER_SIZE);
  if (NewBuffer == NULL) {
    return EFI_OUT_OF_RESOURCES;
  }

  Source      = (UINT8 *) FormBuffer;
  Destination = (UINT8 *) NewBuffer;

  //
  // Copy the IFR Package header to the new buffer
  //
  CopyMem (Destination, Source, sizeof (EFI_HII_PACK_HEADER));

  //
  // Advance Source and Destination to next op-code
  //
  Source      = Source + sizeof (EFI_HII_PACK_HEADER);
  Destination = Destination + sizeof (EFI_HII_PACK_HEADER);

  //
  // Copy data to the new buffer until we run into the end_form
  //
  for (; ((FRAMEWORK_EFI_IFR_OP_HEADER *) Source)->OpCode != FRAMEWORK_EFI_IFR_END_FORM_OP;) {
    //
    // If the this opcode is an end_form_set we better be creating and endform
    // Nonetheless, we will add data before the end_form_set.  This also provides
    // for interesting behavior in the code we will run, but has no bad side-effects
    // since we will possibly do a 0 byte copy in this particular end-case.
    //
    if (((FRAMEWORK_EFI_IFR_OP_HEADER *) Source)->OpCode == FRAMEWORK_EFI_IFR_END_FORM_SET_OP) {
      break;
    }

    //
    // Copy data to new buffer
    //
    CopyMem (Destination, Source, ((FRAMEWORK_EFI_IFR_OP_HEADER *) Source)->Length);

    //
    // Adjust Source/Destination to next op-code location
    //
    Destination = Destination + (UINTN) ((FRAMEWORK_EFI_IFR_OP_HEADER *) Source)->Length;
    Source      = Source + (UINTN) ((FRAMEWORK_EFI_IFR_OP_HEADER *) Source)->Length;
  }

  //
  // Prior to the end_form is where we insert the new op-code data
  //
  CopyMem (Destination, OpCodeData, ((FRAMEWORK_EFI_IFR_OP_HEADER *) OpCodeData)->Length);
  Destination       = Destination + (UINTN) ((FRAMEWORK_EFI_IFR_OP_HEADER *) OpCodeData)->Length;

  NewBuffer->Length = (UINT32) (NewBuffer->Length + (UINT32) (((FRAMEWORK_EFI_IFR_OP_HEADER *) OpCodeData)->Length));

  //
  // Copy end-form data to new buffer
  //
  CopyMem (Destination, Source, ((FRAMEWORK_EFI_IFR_OP_HEADER *) Source)->Length);

  //
  // Adjust Source/Destination to next op-code location
  //
  Destination = Destination + (UINTN) ((FRAMEWORK_EFI_IFR_OP_HEADER *) Source)->Length;
  Source      = Source + (UINTN) ((FRAMEWORK_EFI_IFR_OP_HEADER *) Source)->Length;

  //
  // Copy end-formset data to new buffer
  //
  CopyMem (Destination, Source, ((FRAMEWORK_EFI_IFR_OP_HEADER *) Source)->Length);

  //
  // Zero out the original buffer and copy the updated data in the new buffer to the old buffer
  //
  ZeroMem (FormBuffer, DEFAULT_FORM_BUFFER_SIZE);
  CopyMem (FormBuffer, NewBuffer, DEFAULT_FORM_BUFFER_SIZE);

  //
  // Free the newly created buffer since we don't need it anymore
  //
  gBS->FreePool (NewBuffer);
  return EFI_SUCCESS;
}

/**
  Get the HII protocol interface
  
  @param Hii     HII protocol interface
  
  @return the statue of locating HII protocol
**/
EFI_STATUS
GetHiiInterface (
  OUT     EFI_HII_PROTOCOL    **Hii
  )
{
  EFI_STATUS  Status;

  //
  // There should only be one HII protocol
  //
  Status = gBS->LocateProtocol (
                  &gEfiHiiProtocolGuid,
                  NULL,
                  (VOID **) Hii
                  );

  return Status;;
}

/**
  Extract information pertaining to the HiiHandle
  
  @param HiiHandle       Hii handle
  @param ImageLength     For input, length of DefaultImage;
                         For output, length of actually required
  @param DefaultImage    Image buffer prepared by caller
  @param Guid            Guid information about the form 
  
  @retval EFI_OUT_OF_RESOURCES    No enough buffer to allocate
  @retval EFI_BUFFER_TOO_SMALL    DefualtImage has no enough ImageLength
  @retval EFI_SUCCESS             Successfully extract data from Hii database.
**/
EFI_STATUS
ExtractDataFromHiiHandle (
  IN      FRAMEWORK_EFI_HII_HANDLE       HiiHandle,
  IN OUT  UINT16              *ImageLength,
  OUT     UINT8               *DefaultImage,
  OUT     EFI_GUID            *Guid
  )
{
  EFI_STATUS        Status;
  EFI_HII_PROTOCOL  *Hii;
  UINTN             DataLength;
  UINT8             *RawData;
  UINT8             *OldData;
  UINTN             Index;
  UINTN             Temp;
  UINTN             SizeOfNvStore;
  UINTN             CachedStart;

  DataLength    = DEFAULT_FORM_BUFFER_SIZE;
  SizeOfNvStore = 0;
  CachedStart   = 0;

  Status        = GetHiiInterface (&Hii);

  if (EFI_ERROR (Status)) {
    return Status;
  }

  //
  // Allocate space for retrieval of IFR data
  //
  RawData = AllocateZeroPool (DataLength);
  if (RawData == NULL) {
    return EFI_OUT_OF_RESOURCES;
  }

  //
  // Get all the forms associated with this HiiHandle
  //
  Status = Hii->GetForms (Hii, HiiHandle, 0, &DataLength, RawData);

  if (EFI_ERROR (Status)) {
    gBS->FreePool (RawData);

    //
    // Allocate space for retrieval of IFR data
    //
    RawData = AllocateZeroPool (DataLength);
    if (RawData == NULL) {
      return EFI_OUT_OF_RESOURCES;
    }

    //
    // Get all the forms associated with this HiiHandle
    //
    Status = Hii->GetForms (Hii, HiiHandle, 0, &DataLength, RawData);
  }

  OldData = RawData;

  //
  // Point RawData to the beginning of the form data
  //
  RawData = (UINT8 *) ((UINTN) RawData + sizeof (EFI_HII_PACK_HEADER));

  for (Index = 0; RawData[Index] != FRAMEWORK_EFI_IFR_END_FORM_SET_OP;) {
    switch (RawData[Index]) {
    case FRAMEWORK_EFI_IFR_FORM_SET_OP:
      //
      // Copy the GUID information from this handle
      //
      CopyMem (Guid, &((FRAMEWORK_EFI_IFR_FORM_SET *) &RawData[Index])->Guid, sizeof (EFI_GUID));
      break;

    case FRAMEWORK_EFI_IFR_ONE_OF_OP:
    case FRAMEWORK_EFI_IFR_CHECKBOX_OP:
    case FRAMEWORK_EFI_IFR_NUMERIC_OP:
    case FRAMEWORK_EFI_IFR_DATE_OP:
    case FRAMEWORK_EFI_IFR_TIME_OP:
    case FRAMEWORK_EFI_IFR_PASSWORD_OP:
    case FRAMEWORK_EFI_IFR_STRING_OP:
      //
      // Remember, multiple op-codes may reference the same item, so let's keep a running
      // marker of what the highest QuestionId that wasn't zero length.  This will accurately
      // maintain the Size of the NvStore
      //
      if (((FRAMEWORK_EFI_IFR_ONE_OF *) &RawData[Index])->Width != 0) {
        Temp = ((FRAMEWORK_EFI_IFR_ONE_OF *) &RawData[Index])->QuestionId + ((FRAMEWORK_EFI_IFR_ONE_OF *) &RawData[Index])->Width;
        if (SizeOfNvStore < Temp) {
          SizeOfNvStore = ((FRAMEWORK_EFI_IFR_ONE_OF *) &RawData[Index])->QuestionId + ((FRAMEWORK_EFI_IFR_ONE_OF *) &RawData[Index])->Width;
        }
      }
    }

    Index = RawData[Index + 1] + Index;
  }

  //
  // Return an error if buffer is too small
  //
  if (SizeOfNvStore > *ImageLength) {
    gBS->FreePool (OldData);
    *ImageLength = (UINT16) SizeOfNvStore;
    return EFI_BUFFER_TOO_SMALL;
  }

  if (DefaultImage != NULL) {
    ZeroMem (DefaultImage, SizeOfNvStore);
  }

  //
  // Copy the default image information to the user's buffer
  //
  for (Index = 0; RawData[Index] != FRAMEWORK_EFI_IFR_END_FORM_SET_OP;) {
    switch (RawData[Index]) {
    case FRAMEWORK_EFI_IFR_ONE_OF_OP:
      CachedStart = ((FRAMEWORK_EFI_IFR_ONE_OF *) &RawData[Index])->QuestionId;
      break;

    case FRAMEWORK_EFI_IFR_ONE_OF_OPTION_OP:
      if (((FRAMEWORK_EFI_IFR_ONE_OF_OPTION *) &RawData[Index])->Flags & FRAMEWORK_EFI_IFR_FLAG_DEFAULT) {
        CopyMem (&DefaultImage[CachedStart], &((FRAMEWORK_EFI_IFR_ONE_OF_OPTION *) &RawData[Index])->Value, 2);
      }
      break;

    case FRAMEWORK_EFI_IFR_CHECKBOX_OP:
      DefaultImage[((FRAMEWORK_EFI_IFR_ONE_OF *) &RawData[Index])->QuestionId] = ((FRAMEWORK_EFI_IFR_CHECKBOX *) &RawData[Index])->Flags;
      break;

    case FRAMEWORK_EFI_IFR_NUMERIC_OP:
      CopyMem (
        &DefaultImage[((FRAMEWORK_EFI_IFR_ONE_OF *) &RawData[Index])->QuestionId],
        &((FRAMEWORK_EFI_IFR_NUMERIC *) &RawData[Index])->Default,
        2
        );
      break;

    }

    Index = RawData[Index + 1] + Index;
  }

  *ImageLength = (UINT16) SizeOfNvStore;

  //
  // Free our temporary repository of form data
  //
  gBS->FreePool (OldData);

  return EFI_SUCCESS;
}

/**
  Finds HII handle for given pack GUID previously registered with the HII.
  
  @param HiiProtocol pointer to pointer to HII protocol interface.
                     If NULL, the interface will be found but not returned.
                     If it points to NULL, the interface will be found and
                     written back to the pointer that is pointed to.
  @param Guid        The GUID of the pack that registered with the HII.

  @return  Handle to the HII pack previously registered by the memory driver.
**/
FRAMEWORK_EFI_HII_HANDLE 
FindHiiHandle (
  IN OUT EFI_HII_PROTOCOL    **HiiProtocol, OPTIONAL
  IN     EFI_GUID            *Guid
  )
{
  EFI_STATUS        Status;

  FRAMEWORK_EFI_HII_HANDLE     *HiiHandleBuffer;
  FRAMEWORK_EFI_HII_HANDLE     HiiHandle;
  UINT16            HiiHandleBufferLength;
  UINT32            NumberOfHiiHandles;
  EFI_GUID          HiiGuid;
  EFI_HII_PROTOCOL  *HiiProt;
  UINT32            Index;
  UINT16            Length;

  HiiHandle = 0;
  if ((HiiProtocol != NULL) && (*HiiProtocol != NULL)) {
    //
    // The protocol has been passed in
    //
    HiiProt = *HiiProtocol;
  } else {
    gBS->LocateProtocol (
          &gEfiHiiProtocolGuid,
          NULL,
          (VOID **) &HiiProt
          );
    if (HiiProt == NULL) {
      return HiiHandle;
    }

    if (HiiProtocol != NULL) {
      //
      // Return back the HII protocol for the caller as promissed
      //
      *HiiProtocol = HiiProt;
    }
  }
  //
  // Allocate buffer
  //
  HiiHandleBufferLength = 10;
  HiiHandleBuffer       = AllocatePool (HiiHandleBufferLength);
  ASSERT (HiiHandleBuffer != NULL);

  //
  // Get the Handles of the packages that were registered with Hii
  //
  Status = HiiProt->FindHandles (
                      HiiProt,
                      &HiiHandleBufferLength,
                      HiiHandleBuffer
                      );

  //
  // Get a bigger bugffer if this one is to small, and try again
  //
  if (Status == EFI_BUFFER_TOO_SMALL) {

    gBS->FreePool (HiiHandleBuffer);

    HiiHandleBuffer = AllocatePool (HiiHandleBufferLength);
    ASSERT (HiiHandleBuffer != NULL);

    Status = HiiProt->FindHandles (
                        HiiProt,
                        &HiiHandleBufferLength,
                        HiiHandleBuffer
                        );
  }

  if (EFI_ERROR (Status)) {
    goto lbl_exit;
  }

  NumberOfHiiHandles = HiiHandleBufferLength / sizeof (FRAMEWORK_EFI_HII_HANDLE );

  //
  // Iterate Hii handles and look for the one that matches our Guid
  //
  for (Index = 0; Index < NumberOfHiiHandles; Index++) {

    Length = 0;
    ExtractDataFromHiiHandle (HiiHandleBuffer[Index], &Length, NULL, &HiiGuid);

    if (CompareGuid (&HiiGuid, Guid)) {

      HiiHandle = HiiHandleBuffer[Index];
      break;
    }
  }

lbl_exit:
  gBS->FreePool (HiiHandleBuffer);
  return HiiHandle;
}

/**
  Validate that the data associated with the HiiHandle in NVRAM is within
  the reasonable parameters for that FormSet.  Values for strings and passwords
  are not verified due to their not having the equivalent of valid range settings.

  @param HiiHandle    Handle of the HII database entry to query

  @param Results      If return Status is EFI_SUCCESS, Results provides valid data
                      TRUE  = NVRAM Data is within parameters
                      FALSE = NVRAM Data is NOT within parameters
  @retval EFI_OUT_OF_RESOURCES      No enough buffer to allocate
  @retval EFI_SUCCESS               Data successfully validated
**/
EFI_STATUS
ValidateDataFromHiiHandle (
  IN      FRAMEWORK_EFI_HII_HANDLE       HiiHandle,
  OUT     BOOLEAN             *Results
  )
{
  EFI_STATUS        Status;
  EFI_HII_PROTOCOL  *Hii;
  EFI_GUID          Guid;
  UINT8             *RawData;
  UINT8             *OldData;
  UINTN             RawDataLength;
  UINT8             *VariableData;
  UINTN             Index;
  UINTN             Temp;
  UINTN             SizeOfNvStore;
  UINTN             CachedStart;
  BOOLEAN           GotMatch;

  RawDataLength = DEFAULT_FORM_BUFFER_SIZE;
  SizeOfNvStore = 0;
  CachedStart   = 0;
  GotMatch      = FALSE;
  *Results      = TRUE;

  Status        = GetHiiInterface (&Hii);

  if (EFI_ERROR (Status)) {
    return Status;
  }

  //
  // Allocate space for retrieval of IFR data
  //
  RawData = AllocateZeroPool (RawDataLength);
  if (RawData == NULL) {
    return EFI_OUT_OF_RESOURCES;
  }

  //
  // Get all the forms associated with this HiiHandle
  //
  Status = Hii->GetForms (Hii, HiiHandle, 0, &RawDataLength, RawData);

  if (EFI_ERROR (Status)) {
    gBS->FreePool (RawData);

    //
    // Allocate space for retrieval of IFR data
    //
    RawData = AllocateZeroPool (RawDataLength);
    if (RawData == NULL) {
      return EFI_OUT_OF_RESOURCES;
    }

    //
    // Get all the forms associated with this HiiHandle
    //
    Status = Hii->GetForms (Hii, HiiHandle, 0, &RawDataLength, RawData);
  }

  OldData = RawData;

  //
  // Point RawData to the beginning of the form data
  //
  RawData = (UINT8 *) ((UINTN) RawData + sizeof (EFI_HII_PACK_HEADER));

  for (Index = 0; RawData[Index] != FRAMEWORK_EFI_IFR_END_FORM_SET_OP;) {
    if (RawData[Index] == FRAMEWORK_EFI_IFR_FORM_SET_OP) {
      CopyMem (&Guid, &((FRAMEWORK_EFI_IFR_FORM_SET *) &RawData[Index])->Guid, sizeof (EFI_GUID));
      break;
    }

    Index = RawData[Index + 1] + Index;
  }

  for (Index = 0; RawData[Index] != FRAMEWORK_EFI_IFR_END_FORM_SET_OP;) {
    switch (RawData[Index]) {
    case FRAMEWORK_EFI_IFR_FORM_SET_OP:
      break;

    case FRAMEWORK_EFI_IFR_ONE_OF_OP:
    case FRAMEWORK_EFI_IFR_CHECKBOX_OP:
    case FRAMEWORK_EFI_IFR_NUMERIC_OP:
    case FRAMEWORK_EFI_IFR_DATE_OP:
    case FRAMEWORK_EFI_IFR_TIME_OP:
    case FRAMEWORK_EFI_IFR_PASSWORD_OP:
    case FRAMEWORK_EFI_IFR_STRING_OP:
      //
      // Remember, multiple op-codes may reference the same item, so let's keep a running
      // marker of what the highest QuestionId that wasn't zero length.  This will accurately
      // maintain the Size of the NvStore
      //
      if (((FRAMEWORK_EFI_IFR_ONE_OF *) &RawData[Index])->Width != 0) {
        Temp = ((FRAMEWORK_EFI_IFR_ONE_OF *) &RawData[Index])->QuestionId + ((FRAMEWORK_EFI_IFR_ONE_OF *) &RawData[Index])->Width;
        if (SizeOfNvStore < Temp) {
          SizeOfNvStore = ((FRAMEWORK_EFI_IFR_ONE_OF *) &RawData[Index])->QuestionId + ((FRAMEWORK_EFI_IFR_ONE_OF *) &RawData[Index])->Width;
        }
      }
    }

    Index = RawData[Index + 1] + Index;
  }

  //
  // Allocate memory for our File Form Tags
  //
  VariableData = AllocateZeroPool (SizeOfNvStore);
  if (VariableData == NULL) {
    return EFI_OUT_OF_RESOURCES;
  }

  Status = gRT->GetVariable (
                  (CHAR16 *) L"Setup",
                  &Guid,
                  NULL,
                  &SizeOfNvStore,
                  (VOID *) VariableData
                  );

  if (EFI_ERROR (Status)) {

    //
    // If there is a variable that exists already and it is larger than what we calculated the
    // storage needs to be, we must assume the variable size from GetVariable is correct and not
    // allow the truncation of the variable.  It is very possible that the user who created the IFR
    // we are cracking is not referring to a variable that was in a previous map, however we cannot
    // allow it's truncation.
    //
    if (Status == EFI_BUFFER_TOO_SMALL) {
      //
      // Free the buffer that was allocated that was too small
      //
      gBS->FreePool (VariableData);

      VariableData = AllocatePool (SizeOfNvStore);
      if (VariableData == NULL) {
        return EFI_OUT_OF_RESOURCES;
      }

      Status = gRT->GetVariable (
                      (CHAR16 *) L"Setup",
                      &Guid,
                      NULL,
                      &SizeOfNvStore,
                      (VOID *) VariableData
                      );
    }
  }

  //
  // Walk through the form and see that the variable data it refers to is ok.
  // This allows for the possibility of stale (obsoleted) data in the variable
  // can be overlooked without causing an error
  //
  for (Index = 0; RawData[Index] != FRAMEWORK_EFI_IFR_END_FORM_SET_OP;) {
    switch (RawData[Index]) {
    case FRAMEWORK_EFI_IFR_ONE_OF_OP:
      //
      // A one_of has no data, its the option that does - cache the storage Id
      //
      CachedStart = ((FRAMEWORK_EFI_IFR_ONE_OF *) &RawData[Index])->QuestionId;
      break;

    case FRAMEWORK_EFI_IFR_ONE_OF_OPTION_OP:
      //
      // A one_of_option can be any value
      //
      if (VariableData[CachedStart] == ((FRAMEWORK_EFI_IFR_ONE_OF_OPTION *) &RawData[Index])->Value) {
        GotMatch = TRUE;
      }
      break;

    case FRAMEWORK_EFI_IFR_END_ONE_OF_OP:
      //
      // At this point lets make sure that the data value in the NVRAM matches one of the options
      //
      if (!GotMatch) {
        *Results = FALSE;
        return EFI_SUCCESS;
      }
      break;

    case FRAMEWORK_EFI_IFR_CHECKBOX_OP:
      //
      // A checkbox is a boolean, so 0 and 1 are valid
      // Remember, QuestionId corresponds to the offset location of the data in the variable
      //
      if (VariableData[((FRAMEWORK_EFI_IFR_CHECKBOX *) &RawData[Index])->QuestionId] > 1) {
        *Results = FALSE;
        return EFI_SUCCESS;
      }
      break;

    case FRAMEWORK_EFI_IFR_NUMERIC_OP:
        if ((VariableData[((FRAMEWORK_EFI_IFR_NUMERIC *)&RawData[Index])->QuestionId] < ((FRAMEWORK_EFI_IFR_NUMERIC *)&RawData[Index])->Minimum) ||
            (VariableData[((FRAMEWORK_EFI_IFR_NUMERIC *)&RawData[Index])->QuestionId] > ((FRAMEWORK_EFI_IFR_NUMERIC *)&RawData[Index])->Maximum)) {
        *Results = FALSE;
        return EFI_SUCCESS;
      }
      break;

    }

    Index = RawData[Index + 1] + Index;
  }

  //
  // Free our temporary repository of form data
  //
  gBS->FreePool (OldData);
  gBS->FreePool (VariableData);

  return EFI_SUCCESS;
}