KernelSupport32.c

Go to the documentation of this file.

 
#include "../BootCompatInternal.h"
 
#include <Guid/OcVariable.h>
#include <IndustryStandard/AppleHibernate.h>
 
#include <Library/BaseLib.h>
#include <Library/BaseMemoryLib.h>
#include <Library/DebugLib.h>
#include <Library/OcBootManagementLib.h>
#include <Library/OcDebugLogLib.h>
#include <Library/OcDeviceTreeLib.h>
#include <Library/OcMachoLib.h>
#include <Library/OcMemoryLib.h>
#include <Library/OcMiscLib.h>
#include <Library/OcStringLib.h>
#include <Library/PrintLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/UefiLib.h>
#include <Library/UefiRuntimeServicesTableLib.h>
 
VOID
AppleMapPrepareKernelJump32 (
  IN OUT BOOT_COMPAT_CONTEXT  *BootCompat
  )
{
  UINT8    *KernelEntry;
  UINT32   Offset;
  BOOLEAN  Found;
 
  //
  // There is no reason to patch the kernel when we do not need it.
  //
  if (  !BootCompat->Settings.AvoidRuntimeDefrag
     && !BootCompat->Settings.DiscardHibernateMap
     && !BootCompat->Settings.AllowRelocationBlock
     && !BootCompat->Settings.DisableSingleUser
     && !BootCompat->Settings.ForceBooterSignature)
  {
    return;
  }
 
  //
  // TODO: Add support for 32-bit hibernation some day.
  //
  if (BootCompat->ServiceState.AppleHibernateWake) {
    RUNTIME_DEBUG ((DEBUG_ERROR, "OCABC: Cannot patch 32-bit kernel in hibernate wake!\n"));
    CpuDeadLoop ();
  }
 
  //
  // There are no call gates in 32-bit mode.
  //
  ASSERT (BootCompat->ServiceState.OldKernelCallGate == 0);
 
  //
  // Search for kernel entry point.
  // This sequence seems to be relatively stable for 10.4 ~ 10.6.
  //
  STATIC CONST UINT8  mEntryBytes[] = {
    0x66, 0x8C, 0xDB, 
    0x8E, 0xC3,       
    0x89, 0xC5,       
  };
 
  Offset = 0;
 
  if (BootCompat->KernelState.RelocationBlock != 0) {
    Found = FindPattern (
              mEntryBytes,
              NULL,
              sizeof (mEntryBytes),
              (VOID *)(UINTN)BootCompat->KernelState.RelocationBlock,
              BootCompat->KernelState.RelocationBlockUsed,
              &Offset
              );
  } else {
    Found = FindPattern (
              mEntryBytes,
              NULL,
              sizeof (mEntryBytes),
              (VOID *)(UINTN)KERNEL_BASE_PADDR,
              BASE_2MB,
              &Offset
              );
  }
 
  if (!Found) {
    RUNTIME_DEBUG ((DEBUG_ERROR, "OCABC: No 32-bit kernel entry!\n"));
    CpuDeadLoop ();
  }
 
  KernelEntry    = (VOID *)(UINTN)(KERNEL_BASE_PADDR + Offset);
  KernelEntry[0] = 0xE8; 
  Offset         = (UINTN)((UINTN)AsmAppleMapPrepareKernelState32 - (UINTN)KernelEntry - 5);
  CopyMem (&KernelEntry[1], &Offset, sizeof (UINT32));
}
 
UINTN
EFIAPI
AppleMapPrepareKernelState32 (
  IN UINTN  Args
  )
{
  BOOT_COMPAT_CONTEXT  *BootCompat;
 
  BootCompat = GetBootCompatContext ();
 
  if (BootCompat->ServiceState.AppleHibernateWake) {
    //
    // TODO: This is not really implemented.
    //
    AppleMapPrepareForHibernateWake (
      BootCompat,
      Args
      );
  } else {
    AppleMapPrepareForBooting (
      BootCompat,
      (VOID *)Args
      );
  }
 
  if (BootCompat->KernelState.RelocationBlock != 0) {
    Args -= (UINTN)(BootCompat->KernelState.RelocationBlock - KERNEL_BASE_PADDR);
 
    //
    // FIXME: This should be done via trampoline as we may overwrite ourselves.
    // See RelocationCallGate.nasm for more details.
    //
    CopyMem (
      (VOID *)(UINTN)KERNEL_BASE_PADDR,
      (VOID *)(UINTN)BootCompat->KernelState.RelocationBlock,
      BootCompat->KernelState.RelocationBlockUsed
      );
  }
 
  return Args;
}