我扫描我的进程的打开句柄并在控制台中打印它们。
此时的奇怪问题如下，检查代码：
array<Accessor^>^ AntiCheat::ScanHandles()
{
List<Accessor^>^ accessorList = gcnew List<Accessor^>();
if (!EnableDebugPrivilege(true))
printf("EnableDebugPrivilege failed: %d\n", GetLastError());
tNtQuerySystemInformation oNtQuerySystemInformation = (tNtQuerySystemInformation)GetProcAddress(GetModuleHandle("ntdll.dll"), "NtQuerySystemInformation");
PSYSTEM_HANDLE_INFORMATION handleInfo = new SYSTEM_HANDLE_INFORMATION;
SYSTEM_INFORMATION_CLASS infoClass = (SYSTEM_INFORMATION_CLASS)16; // SystemHandleInformation
DWORD size = sizeof(SYSTEM_HANDLE_INFORMATION);
DWORD needed = 0;
NTSTATUS status = oNtQuerySystemInformation(infoClass, handleInfo, size, &needed);
while (!NT_SUCCESS(status))
{
if (needed == 0)
return nullptr;
// The previously supplied buffer wasn't enough.
delete handleInfo;
size = needed + 1024;
handleInfo = (PSYSTEM_HANDLE_INFORMATION)new BYTE[size];
status = oNtQuerySystemInformation(infoClass, handleInfo, size, &needed);
}
HANDLE currentProcess = GetCurrentProcess();
DWORD currentProcessId = GetProcessId(currentProcess);
for (DWORD i = 0; i < handleInfo->dwCount; i++)
{
//printf(".");
SYSTEM_HANDLE handle = handleInfo->Handles[i];
HANDLE procHandle = OpenProcess(PROCESS_DUP_HANDLE | PROCESS_QUERY_INFORMATION | PROCESS_VM_READ, false, handle.dwProcessId);
if (GetLastError() == ERROR_ACCESS_DENIED)
continue;
HANDLE dupl = 0;
if (!DuplicateHandle(procHandle, (HANDLE)handle.wValue, currentProcess, &dupl, 0, false, DUPLICATE_SAME_ACCESS))
continue;
DWORD procId = GetProcessId(dupl);
if (procId == currentProcessId)
{
printf("accessing us\n");
char processName[MAX_PATH];
GetModuleFileNameEx((HMODULE)procHandle, NULL, processName, MAX_PATH);
accessorList->Add(gcnew Accessor(gcnew String(processName), handle.GrantedAccess));
}
CloseHandle(dupl);
}
return accessorList->ToArray();
}
如果我用printf（＆＃34;。＆＃34;）;取消注释该行，我会看到3个打开的句柄（cheatengine）。如果它被评论（运行方式更快），则没有打开的句柄。但是，我不知道为什么这会影响我的代码。我很惊讶，有谁知道为什么会这样？或者如何在没有我的printf的情况下找到如何找到句柄（＆＃34;。＆＃34;）;线？
另一个问题是：每次调用该函数时，分配的字节数都会重复。而且我不知道为什么。
答案 0 :(得分：1)
我发现您的代码存在逻辑问题。
您不会忽略handle.dwProcessId等于currentProcessId的数组项，因此您最终会打开自己进程的句柄。由于您只想查找其他流程，因此应忽略handle.dwProcessId等于currentProcessId的项目。
您不会因OpenProcess()以外的任何原因检查ERROR_ACCESS_DENIED是否失败。除非GetLastError()实际上首先返回NULL，否则不要调用OpenProcess()。
如果DuplicateHandle()失败，您没有关闭已打开的句柄。为什么要复制每个源句柄只是为了调用它上面的GetProcessId()？您已经拥有了数组中的进程ID，因此整个DuplicateHandle() + GetProcessId()完全没必要。
无论如何，你采取的是错误的做法。看看这个讨论：
Enumerating the processes referencing an object
使用NtQuerySystemInformation并将SystemInformationClass设置为SystemHandleInformation。这将填充一系列SYSTEM_HANDLE_INFORMATION结构，这些结构定义为：
typedef struct _SYSTEM_HANDLE_INFORMATION { ULONG ProcessId; UCHAR ObjectTypeNumber; UCHAR Flags; USHORT Handle; PVOID Object; ACCESS_MASK GrantedAccess; } SYSTEM_HANDLE_INFORMATION;搜索与您使用ProcessID等于GetCurrentProcessId（）打开的句柄对应的条目，然后查找具有相同Object指针的所有条目。
虽然讨论显示SYSTEM_HANDLE_INFORMATION的错误声明。以下文章显示了正确的一个：
#define SystemHandleInformation 16 typedef NTSTATUS (NTAPI *_NtQuerySystemInformation)( ULONG SystemInformationClass, PVOID SystemInformation, ULONG SystemInformationLength, PULONG ReturnLength ); /* The following structure is actually called SYSTEM_HANDLE_TABLE_ENTRY_INFO, but SYSTEM_HANDLE is shorter. */ typedef struct _SYSTEM_HANDLE { ULONG ProcessId; BYTE ObjectTypeNumber; BYTE Flags; USHORT Handle; PVOID Object; ACCESS_MASK GrantedAccess; } SYSTEM_HANDLE, *PSYSTEM_HANDLE; typedef struct _SYSTEM_HANDLE_INFORMATION { ULONG HandleCount; /* Or NumberOfHandles if you prefer. */ SYSTEM_HANDLE Handles[1]; } SYSTEM_HANDLE_INFORMATION, *PSYSTEM_HANDLE_INFORMATION;
话虽如此，尝试更像这样的事情：
array<Accessor^>^ AntiCheat::ScanHandles()
{
List<Accessor^>^ accessorList = gcnew List<Accessor^>();
if (!EnableDebugPrivilege(true))
printf("EnableDebugPrivilege failed: %d\n", GetLastError());
tNtQuerySystemInformation oNtQuerySystemInformation = (tNtQuerySystemInformation) GetProcAddress(GetModuleHandle("ntdll.dll"), "NtQuerySystemInformation");
DWORD currentProcessId = GetCurrentProcessId();
HANDLE currentProcess = OpenProcess(PROCESS_ALL_ACCESS, FALSE, currentProcessId);
PVOID currentProcessAddr = nullptr;
DWORD size = sizeof(SYSTEM_HANDLE_INFORMATION);
DWORD needed = 0;
PSYSTEM_HANDLE_INFORMATION handleInfo = (PSYSTEM_HANDLE_INFORMATION) new BYTE[size];
SYSTEM_INFORMATION_CLASS infoClass = (SYSTEM_INFORMATION_CLASS) 16; // SystemHandleInformation
NTSTATUS status = oNtQuerySystemInformation(infoClass, handleInfo, size, &needed);
while (status == STATUS_INFO_LENGTH_MISMATCH)
{
// The previously supplied buffer wasn't enough.
delete[] handleInfo;
size += 1024;
handleInfo = (PSYSTEM_HANDLE_INFORMATION) new BYTE[size];
status = oNtQuerySystemInformation(infoClass, handleInfo, size, &needed);
}
if (status != 0)
{
delete[] handleInfo;
return nullptr;
}
for (DWORD i = 0; i < handleInfo->dwCount; i++)
{
SYSTEM_HANDLE &handle = handleInfo->Handles[i];
if ((handle.dwProcessId == currentProcessId) &&
(currentProcess == (HANDLE)handle.wValue))
{
currentProcessAddr = handle.pAddress;
break;
}
}
for (DWORD i = 0; i < handleInfo->dwCount; i++)
{
SYSTEM_HANDLE &handle = handleInfo->Handles[i];
if ((handle.dwProcessId != currentProcessId) &&
(handle.pAddress == currentProcessAddr))
{
printf("accessing us\n");
HANDLE procHandle = OpenProcess(PROCESS_QUERY_INFORMATION | PROCESS_VM_READ, false, handle.dwProcessId);
if (procHandle != 0)
{
char processName[MAX_PATH+1];
DWORD len = GetModuleFileNameEx((HMODULE)procHandle, NULL, processName, MAX_PATH);
CloseHandle(procHandle);
processName[len] = '\0';
accessorList->Add(gcnew Accessor(gcnew String(processName), handle.GrantedAccess));
}
else
accessorList->Add(gcnew Accessor(gcnew String("unknown"), handle.GrantedAccess));
}
}
CloseHandle(currentProcess);
delete[] handleInfo;
return accessorList->ToArray();
}