C++实现inline hook的原理及应用实例

#include <ntifs.h>
#include <windef.h>
ULONG g_KiInsertQueueApc;
ULONG g_uCr0;
BYTE g_HookCode[5] = { 0xe9, 0, 0, 0, 0 }; //JMP NEAR
BYTE g_OrigCode[5] = { 0 }; // 原函数的前字节内容
BYTE jmp_orig_code[7] = { 0xEA, 0, 0, 0, 0, 0x08, 0x00 }; //JMP FAR
BOOL g_bHooked = FALSE;
VOID
fake_KiInsertQueueApc (
            PKAPC Apc,
            KPRIORITY Increment
            );
VOID
Proxy_KiInsertQueueApc (
            PKAPC Apc,
            KPRIORITY Increment
            );
void WPOFF()
{
  ULONG uAttr;
  _asm
  {
    push eax;
    mov eax, cr0;
    mov uAttr, eax;
    and eax, 0FFFEFFFFh; // CR0 16 BIT = 0
    mov cr0, eax;
    pop eax;
    cli
  };
  g_uCr0 = uAttr; //保存原有的 CRO 屬性
}
VOID WPON()
{
  _asm
  {
    sti
      push eax;
    mov eax, g_uCr0; //恢復原有 CR0 屬性
    mov cr0, eax;
    pop eax;
  };
}
//
// 停止inline hook
//
VOID UnHookKiInsertQueueApc ()
{
  KIRQL oldIrql;
  WPOFF();
  oldIrql = KeRaiseIrqlToDpcLevel();
  RtlCopyMemory ( (BYTE*)g_KiInsertQueueApc, g_OrigCode, 5 );
  KeLowerIrql(oldIrql);
  WPON();
  g_bHooked = FALSE;
}
//
// 开始inline hook -- KiInsertQueueApc
//
VOID HookKiInsertQueueApc ()
{
  KIRQL oldIrql;
  if (g_KiInsertQueueApc == 0) {
    DbgPrint("KiInsertQueueApc == NULL\n");
    return;
  }
  //DbgPrint("开始inline hook -- KiInsertQueueApc\n");
  DbgPrint( "KiInsertQueueApc的地址t0x%08x\n", (ULONG)g_KiInsertQueueApc );
  DbgPrint( "fake_KiInsertQueueApc的地址t0x%08x\n", (ULONG)fake_KiInsertQueueApc );
  
  // 保存原函数的前字节内容
  RtlCopyMemory (g_OrigCode, (BYTE*)g_KiInsertQueueApc, 5);
  //jmp指令，此处为短跳，计算相对偏移，同时，jmp xxxxxx这条指令占了5个字节
  *( (ULONG*)(g_HookCode + 1) ) = (ULONG)fake_KiInsertQueueApc - (ULONG)g_KiInsertQueueApc - 5;
  // 禁止系统写保护，提升IRQL到DPC
  WPOFF();
  oldIrql = KeRaiseIrqlToDpcLevel();
  RtlCopyMemory ( (BYTE*)g_KiInsertQueueApc, g_HookCode, 5 );
  *( (ULONG*)(jmp_orig_code + 1) ) = (ULONG) ( (BYTE*)g_KiInsertQueueApc + 5 );
  RtlCopyMemory ( (BYTE*)Proxy_KiInsertQueueApc, g_OrigCode, 5);
  RtlCopyMemory ( (BYTE*)Proxy_KiInsertQueueApc + 5, jmp_orig_code, 7);
  // 恢复写保护，降低IRQL
  KeLowerIrql(oldIrql);
  WPON();
  g_bHooked = TRUE;
}
//
// 跳转到我们的函数里面进行预处理，裸函数，有调用者进行堆栈的平衡
//
__declspec (naked)
VOID
fake_KiInsertQueueApc (
            PKAPC Apc,
            KPRIORITY Increment
            )
{
  // 去掉DbgPrint,不然这个hook会产生递归
  //DbgPrint("inline hook -- KiInsertQueueApc 成功\n");
  __asm
  {
    jmp Proxy_KiInsertQueueApc
  }
}
//
// 代理函数，负责跳转到原函数中继续执行
//
__declspec (naked)
VOID
Proxy_KiInsertQueueApc (
            PKAPC Apc,
            KPRIORITY Increment
            )
{
  __asm { // 共字节
    _emit 0x90
      _emit 0x90
      _emit 0x90
      _emit 0x90
      _emit 0x90 // 前字节实现原函数的头字节功能
      _emit 0x90 // 这个填充jmp
      _emit 0x90
      _emit 0x90
      _emit 0x90
      _emit 0x90 // 这字节保存原函数+5处的地址
      _emit 0x90 
      _emit 0x90 // 因为是长转移,所以必须是0x0080
  }
}
ULONG GetFunctionAddr( IN PCWSTR FunctionName)
{
  UNICODE_STRING UniCodeFunctionName;
  RtlInitUnicodeString( &UniCodeFunctionName, FunctionName );
  return (ULONG)MmGetSystemRoutineAddress( &UniCodeFunctionName ); 
}
//根据特征值，从KeInsertQueueApc搜索中搜索KiInsertQueueApc
ULONG FindKiInsertQueueApcAddress()
{
  char * Addr_KeInsertQueueApc = 0;
  int i = 0;
  char Findcode[] = { 0xE8, 0xcc, 0x29, 0x00, 0x00 };
  ULONG Addr_KiInsertQueueApc = 0;
  Addr_KeInsertQueueApc = (char *) GetFunctionAddr(L"KeInsertQueueApc");
  for(i = 0; i < 100; i ++)
  {
    if( Addr_KeInsertQueueApc[i] == Findcode[0] &&
      Addr_KeInsertQueueApc[i + 1] == Findcode[1] &&
      Addr_KeInsertQueueApc[i + 2] == Findcode[2] &&
      Addr_KeInsertQueueApc[i + 3] == Findcode[3] &&
      Addr_KeInsertQueueApc[i + 4] == Findcode[4]
    )
    {
      Addr_KiInsertQueueApc = (ULONG)&Addr_KeInsertQueueApc[i] + 0x29cc + 5;
      break;
    }
  }
  return Addr_KiInsertQueueApc;
}
VOID OnUnload( IN PDRIVER_OBJECT DriverObject )
{
  DbgPrint("My Driver Unloaded!");
  UnHookKiInsertQueueApc();
}
NTSTATUS DriverEntry( IN PDRIVER_OBJECT theDriverObject, IN PUNICODE_STRING theRegistryPath )
{
  DbgPrint("My Driver Loaded!");
  theDriverObject->DriverUnload = OnUnload;
  g_KiInsertQueueApc = FindKiInsertQueueApcAddress();
  HookKiInsertQueueApc();
  return STATUS_SUCCESS;
}