AIKTarget.c

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#include "AIKTarget.h"
#include "AIKTranslate.h"
 
#include <Library/BaseMemoryLib.h>
#include <Library/DebugLib.h>
#include <Library/UefiBootServicesTableLib.h>
 
EFI_STATUS
AIKTargetInstall (
  IN OUT AIK_TARGET  *Target,
  IN     UINT8       KeyForgotThreshold
  )
{
  EFI_STATUS  Status;
 
  Status = EFI_SUCCESS;
 
  Target->KeyForgotThreshold = KeyForgotThreshold;
 
  if (Target->KeyMapDb == NULL) {
    Status = gBS->LocateProtocol (&gAppleKeyMapDatabaseProtocolGuid, NULL, (VOID **)&Target->KeyMapDb);
 
    if (EFI_ERROR (Status)) {
      DEBUG ((DEBUG_INFO, "AppleKeyMapDatabaseProtocol is unavailable - %r\n", Status));
      return EFI_NOT_FOUND;
    }
 
    Status = Target->KeyMapDb->CreateKeyStrokesBuffer (
                                 Target->KeyMapDb,
                                 AIK_TARGET_BUFFER_SIZE,
                                 &Target->KeyMapDbIndex
                                 );
 
    if (EFI_ERROR (Status)) {
      DEBUG ((DEBUG_INFO, "CreateKeyStrokesBuffer failed - %r\n", Status));
      Target->KeyMapDb = NULL;
    }
  }
 
  return Status;
}
 
VOID
AIKTargetUninstall (
  IN OUT AIK_TARGET  *Target
  )
{
  if (Target->KeyMapDb != NULL) {
    Target->KeyMapDb->RemoveKeyStrokesBuffer (Target->KeyMapDb, Target->KeyMapDbIndex);
    Target->KeyMapDb = NULL;
  }
 
  Target->NumberOfKeys    = 0;
  Target->Modifiers       = 0;
  Target->ModifierCounter = 0;
  ZeroMem (Target->Keys, sizeof (Target->Keys));
  ZeroMem (Target->KeyCounters, sizeof (Target->KeyCounters));
}
 
UINT64
AIKTargetRefresh (
  IN OUT AIK_TARGET  *Target
  )
{
  UINTN  Index;
  UINTN  Left;
 
  Target->Counter++;
 
  for (Index = 0; Index < Target->NumberOfKeys; Index++) {
    //
    // We reported this key Target->KeyForgetThreshold times, time to say goodbye.
    //
    if (Target->KeyCounters[Index] + Target->KeyForgotThreshold <= Target->Counter) {
      Left = Target->NumberOfKeys - (Index + 1);
      if (Left > 0) {
        CopyMem (
          &Target->KeyCounters[Index],
          &Target->KeyCounters[Index+1],
          sizeof (Target->KeyCounters[0]) * Left
          );
        CopyMem (
          &Target->Keys[Index],
          &Target->Keys[Index+1],
          sizeof (Target->Keys[0]) * Left
          );
      }
 
      Target->NumberOfKeys--;
    }
  }
 
  //
  // No keys were pressed, so we did not enter AIKTargetWriteEntry.
  // However, we still need to reset modifiers after time.
  //
  if (Target->ModifierCounter + Target->KeyForgotThreshold <= Target->Counter) {
    Target->Modifiers = 0;
  }
 
  return Target->Counter;
}
 
VOID
AIKTargetWriteEntry (
  IN OUT AIK_TARGET        *Target,
  IN     AMI_EFI_KEY_DATA  *KeyData
  )
{
  APPLE_MODIFIER_MAP  Modifiers;
  APPLE_KEY_CODE      Key;
  UINTN               Index;
  UINTN               InsertIndex;
  UINT64              OldestCounter;
 
  AIKTranslate (KeyData, &Modifiers, &Key);
 
  Target->Modifiers       = Modifiers;
  Target->ModifierCounter = Target->Counter;
 
  if (Key == UsbHidUndefined) {
    //
    // This is just a modifier or an unsupported key.
    //
    return;
  }
 
  for (Index = 0; Index < Target->NumberOfKeys; Index++) {
    if (Target->Keys[Index] == Key) {
      //
      // This key was added previously, just update its counter.
      //
      Target->KeyCounters[Index] = Target->Counter;
      return;
    }
  }
 
  InsertIndex = Target->NumberOfKeys;
 
  //
  // This should not happen, but we have no room, replace the oldest key.
  //
  if (InsertIndex == AIK_TARGET_BUFFER_SIZE) {
    InsertIndex   = 0;
    OldestCounter = Target->KeyCounters[InsertIndex];
    for (Index = 1; Index < Target->NumberOfKeys; Index++) {
      if (OldestCounter > Target->KeyCounters[Index]) {
        OldestCounter = Target->KeyCounters[Index];
        InsertIndex   = Index;
      }
    }
 
    Target->NumberOfKeys--;
  }
 
  //
  // Insert the new key
  //
  Target->Keys[InsertIndex]        = Key;
  Target->KeyCounters[InsertIndex] = Target->Counter;
  Target->NumberOfKeys++;
}
 
VOID
AIKTargetSubmit (
  IN OUT AIK_TARGET  *Target
  )
{
  EFI_STATUS  Status;
 
  if (Target->KeyMapDb != NULL) {
    Status = Target->KeyMapDb->SetKeyStrokeBufferKeys (
                                 Target->KeyMapDb,
                                 Target->KeyMapDbIndex,
                                 Target->Modifiers,
                                 Target->NumberOfKeys,
                                 Target->Keys
                                 );
  } else {
    Status = EFI_NOT_FOUND;
  }
 
  if (EFI_ERROR (Status)) {
    DEBUG ((DEBUG_INFO, "Failed to submit keys to AppleMapDb - %r\n", Status));
  }
}