对象回调存储在对应对象结构体里,简单来说,就是存储在 ObjectType. CallbackList 这
个双向链表里。但对象结构体在每个系统上都不一定相同。比如 WIN7X64 的结构体如下:
ntdll!_OBJECT_TYPE
+0x000 TypeList : _LIST_ENTRY
+0x010 Name : _UNICODE_STRING
+0x020 DefaultObject : Ptr64 Void
+0x028 Index : UChar
+0x02c TotalNumberOfObjects : Uint4B
+0x030 TotalNumberOfHandles : Uint4B
+0x034 HighWaterNumberOfObjects : Uint4B
+0x038 HighWaterNumberOfHandles : Uint4B
+0x040 TypeInfo : _OBJECT_TYPE_INITIALIZER
+0x0b0 TypeLock : _EX_PUSH_LOCK
+0x0b8 Key : Uint4B
+0x0c0 CallbackList : _LIST_ENTRY
Object.CallbackList->FLink 指向的地址,是一个结构体链表,它的定义如下:
typedef struct _OB_CALLBACK
{
LIST_ENTRY ListEntry;
ULONG64 Unknown;
ULONG64 ObHandle;
ULONG64 ObjTypeAddr;
ULONG64 PreCall;
ULONG64 PostCall;
} OB_CALLBACK, *POB_CALLBACK
微软没有公开这个结构体的定义,这个结构体是资料作者逆向出来的。但是至少在 WIN7、WIN8和 WIN8.1 上通用。知道了结构体的定义,枚举就方便了(WINDOWS 目前仅有进程对象回调和线程对象回调,但就算以后有了其它回调,也是通用的):
ULONG EnumObCallbacks()
{
ULONG c=0;
PLIST_ENTRY CurrEntry=NULL;
POB_CALLBACK pObCallback;
BOOLEAN IsTxCallback;
ULONG64 ObProcessCallbackListHead = *(ULONG64*)PsProcessType + ObjectCallbackListOffset;
ULONG64 ObThreadCallbackListHead = *(ULONG64*)PsThreadType + ObjectCallbackListOffset;
//
dprintf("ObProcessCallbackListHead: %p\n",ObProcessCallbackListHead);
CurrEntry=((PLIST_ENTRY)ObProcessCallbackListHead)->Flink; //list_head的数据是垃圾数据,忽略
do
{
pObCallback=(POB_CALLBACK)CurrEntry;
if(pObCallback->ObHandle!=0)
{
dprintf("ObHandle: %p\n",pObCallback->ObHandle);
dprintf("PreCall: %p\n",pObCallback->PreCall);
dprintf("PostCall: %p\n",pObCallback->PostCall);
c++;
}
CurrEntry = CurrEntry->Flink;
}
while(CurrEntry != (PLIST_ENTRY)ObProcessCallbackListHead);
//
dprintf("ObThreadCallbackListHead: %p\n",ObThreadCallbackListHead);
CurrEntry=((PLIST_ENTRY)ObThreadCallbackListHead)->Flink; //list_head的数据是垃圾数据,忽略
do
{
pObCallback=(POB_CALLBACK)CurrEntry;
if(pObCallback->ObHandle!=0)
{
dprintf("ObHandle: %p\n",pObCallback->ObHandle);
dprintf("PreCall: %p\n",pObCallback->PreCall);
dprintf("PostCall: %p\n",pObCallback->PostCall);
c++;
}
CurrEntry = CurrEntry->Flink;
}
while(CurrEntry != (PLIST_ENTRY)ObThreadCallbackListHead);
dprintf("ObCallback count: %ld\n",c);
return c;
}
执行结果:
对付对象回调,方法还是老三套
1.用 ObUnRegisterCallbacks 传入 ObHandle 注销回调;
2.把记录的回调函数地址改为自己的设置的空回调;
3.给对方设置的回调函数地址写入 RET。
不过这次使用第三种方法要注意,必须先禁掉 PostCall,再禁用 PreCall,否则容易蓝屏。
完整代码:
#define dprintf DbgPrint
#define DEVICE_NAME L"\\Device\\MyDriver"
#define LINK_NAME L"\\DosDevices\\MyDriver"
#define LINK_GLOBAL_NAME L"\\DosDevices\\Global\\MyDriver"
ULONG NtBuildNumber=0;
ULONG ObjectCallbackListOffset=0;
typedef struct _OB_CALLBACK
{
LIST_ENTRY ListEntry;
ULONG64 Unknown;
ULONG64 ObHandle;
ULONG64 ObjTypeAddr;
ULONG64 PreCall;
ULONG64 PostCall;
} OB_CALLBACK, *POB_CALLBACK;
BOOLEAN GetVersionAndHardCode()
{
BOOLEAN b=FALSE;
RTL_OSVERSIONINFOW osi;
osi.dwOSVersionInfoSize=sizeof(RTL_OSVERSIONINFOW);
RtlFillMemory(&osi,sizeof(RTL_OSVERSIONINFOW),0);
RtlGetVersion(&osi);
NtBuildNumber=osi.dwBuildNumber;
DbgPrint("NtBuildNumber: %ld\n",NtBuildNumber);
switch (NtBuildNumber)
{
case 7600:
case 7601:
{
ObjectCallbackListOffset=0xC0;
b=TRUE;
break;
}
case 9200:
{
ObjectCallbackListOffset=0xC8; //OBJECT_TYPE.CallbackList
b=TRUE;
break;
}
case 9600:
{
ObjectCallbackListOffset=0xC8; //OBJECT_TYPE.CallbackList
b=TRUE;
break;
}
default:
break;
}
return b;
}
KIRQL WPOFFx64()
{
KIRQL irql=KeRaiseIrqlToDpcLevel();
UINT64 cr0=__readcr0();
cr0 &= 0xfffffffffffeffff;
__writecr0(cr0);
_disable();
return irql;
}
void WPONx64(KIRQL irql)
{
UINT64 cr0=__readcr0();
cr0 |= 0x10000;
_enable();
__writecr0(cr0);
KeLowerIrql(irql);
}
VOID DisableObcallbacks(PVOID Address)
{
KIRQL irql;
CHAR patchCode[] = "\x33\xC0\xC3"; //xor eax,eax + ret
if(!Address)
return;
if(MmIsAddressValid(Address))
{
irql=WPOFFx64();
memcpy(Address,patchCode,3);
WPONx64(irql);
}
}
ULONG EnumObCallbacks()
{
ULONG c=0;
PLIST_ENTRY CurrEntry=NULL;
POB_CALLBACK pObCallback;
BOOLEAN IsTxCallback;
ULONG64 ObProcessCallbackListHead = *(ULONG64*)PsProcessType + ObjectCallbackListOffset;
ULONG64 ObThreadCallbackListHead = *(ULONG64*)PsThreadType + ObjectCallbackListOffset;
//
dprintf("ObProcessCallbackListHead: %p\n",ObProcessCallbackListHead);
CurrEntry=((PLIST_ENTRY)ObProcessCallbackListHead)->Flink; //list_head的数据是垃圾数据,忽略
do
{
pObCallback=(POB_CALLBACK)CurrEntry;
if(pObCallback->ObHandle!=0)
{
dprintf("ObHandle: %p\n",pObCallback->ObHandle);
dprintf("PreCall: %p\n",pObCallback->PreCall);
dprintf("PostCall: %p\n",pObCallback->PostCall);
c++;
}
CurrEntry = CurrEntry->Flink;
}
while(CurrEntry != (PLIST_ENTRY)ObProcessCallbackListHead);
//
dprintf("ObThreadCallbackListHead: %p\n",ObThreadCallbackListHead);
CurrEntry=((PLIST_ENTRY)ObThreadCallbackListHead)->Flink; //list_head的数据是垃圾数据,忽略
do
{
pObCallback=(POB_CALLBACK)CurrEntry;
if(pObCallback->ObHandle!=0)
{
dprintf("ObHandle: %p\n",pObCallback->ObHandle);
dprintf("PreCall: %p\n",pObCallback->PreCall);
dprintf("PostCall: %p\n",pObCallback->PostCall);
c++;
}
CurrEntry = CurrEntry->Flink;
}
while(CurrEntry != (PLIST_ENTRY)ObThreadCallbackListHead);
dprintf("ObCallback count: %ld\n",c);
return c;
}
宋孖健,13