c++ - OpenProcess() Access_Denied 与 SeDebugPrivilege

Question

此程序枚举所有句柄并获取它们的名称。

对于 pID 4，OpenProcess 使用 SeDebugPrivilege 获得错误 5。

UAC 关闭。从管理员运行。

启用 SeDebugPrivilege

BOOL EnableDebugPrivilege(BOOL bEnable)
{
HANDLE hToken = nullptr;
LUID luid;

if (!OpenProcessToken(GetCurrentProcess(), TOKEN_ADJUST_PRIVILEGES, &hToken)) return FALSE;
if (!LookupPrivilegeValue(NULL, SE_DEBUG_NAME, &luid)) return FALSE;
TOKEN_PRIVILEGES tokenPriv;
tokenPriv.PrivilegeCount = 1;
tokenPriv.Privileges[0].Luid = luid;
tokenPriv.Privileges[0].Attributes = bEnable ? SE_PRIVILEGE_ENABLED : 0;
if (!AdjustTokenPrivileges(hToken, FALSE, &tokenPriv, sizeof(TOKEN_PRIVILEGES), NULL, NULL)) return FALSE;
_tprintf(_T("Privileges error: %d\n", GetLastError()));
return TRUE;
}

枚举句柄

DWORD EnumerateFileHandles(ULONG pid)
{
    HINSTANCE hNtDll = LoadLibrary(_T("ntdll.dll"));
    assert(hNtDll != NULL);
    PFN_NTQUERYSYSTEMINFORMATION NtQuerySystemInformation =
        (PFN_NTQUERYSYSTEMINFORMATION)GetProcAddress(hNtDll,
            "NtQuerySystemInformation");
    assert(NtQuerySystemInformation != NULL);
    PFN_NTQUERYINFORMATIONFILE NtQueryInformationFile =
        (PFN_NTQUERYINFORMATIONFILE)GetProcAddress(hNtDll,
            "NtQueryInformationFile");
    DWORD nSize = 4096, nReturn;
    PSYSTEM_HANDLE_INFORMATION pSysHandleInfo = (PSYSTEM_HANDLE_INFORMATION)
        HeapAlloc(GetProcessHeap(), 0, nSize);
    while (NtQuerySystemInformation(SystemExtendedHandleInformation, pSysHandleInfo,
        nSize, &nReturn) == STATUS_INFO_LENGTH_MISMATCH)
    {
        HeapFree(GetProcessHeap(), 0, pSysHandleInfo);
        nSize += 4096;
        pSysHandleInfo = (SYSTEM_HANDLE_INFORMATION*)HeapAlloc(
            GetProcessHeap(), 0, nSize);
    }
    DWORD dwFiles = 0;
    _tprintf(_T("Handles Number: %d\n"), pSysHandleInfo->NumberOfHandles);
    for (ULONG i = 0; i < pSysHandleInfo->NumberOfHandles; i++)
    {
        PSYSTEM_HANDLE pHandle = &(pSysHandleInfo->Handles[i]);
        if (pHandle->ProcessId == 4)
        {
            HANDLE hProcess = OpenProcess(
                PROCESS_DUP_HANDLE, FALSE, pHandle->ProcessId);
            if (hProcess == NULL)
            {
                _tprintf(_T("OpenProcess failed w/err 0x%08lx\n"), GetLastError());
                continue;
            }
            HANDLE hCopy;
            if (!DuplicateHandle(hProcess, (HANDLE)pHandle->Handle,
                GetCurrentProcess(), &hCopy, MAXIMUM_ALLOWED, FALSE, 0))
                continue;
            TCHAR buf[MAX_PATH];
            if (GetFinalPathNameByHandle(hCopy, buf, sizeof(buf), VOLUME_NAME_DOS))
                wprintf(L"p%d:h%d:t%d:\t%s\n", pHandle->ProcessId, pHandle->Handle, pHandle->ObjectTypeNumber, buf);
            CloseHandle(hProcess);
            CloseHandle(hCopy);
        }
    }
    HeapFree(GetProcessHeap(), 0, pSysHandleInfo);
    return dwFiles;
}

在 Windows 7 x64 上它工作正常。但在 Windows 10 x64 上，OpenProcess 使用 SeDebugPrivilege 返回错误 5。

如何在 Windows 10 上打开系统进程(pID 4)。

Answer 1

您不能将它的句柄打开为 documentation对于 OpenProcess 特别说明它会失败:

If the specified process is the Idle process or one of the CSRSS processes, this function fails and the last error code is ERROR_ACCESS_DENIED because their access restrictions prevent user-level code from opening them.

如果你想获取系统进程名称，你可以尝试使用CreateToolhelp32Snapshot()获取进程的快照，然后使用Process32First()和Process32Next() 枚举所有进程。这是一个例子:

#include <iostream> 
#include <stdio.h>
#include <windows.h>
#include <string> 
#include <TlHelp32.h> 
using namespace std;
int main()
{
    PROCESSENTRY32 pe32;
    pe32.dwSize = sizeof(pe32);
    HANDLE hProcessSnap = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);//get the snapshot 
    if (hProcessSnap == INVALID_HANDLE_VALUE) 
    {
        cout << "CreateToolhelp32Snapshot Error!" << endl;
        return false;
    }
    BOOL bResult = Process32First(hProcessSnap, &pe32);
    int num(0);
    while(bResult)
    {
        cout << "[" << ++num << "] : " << "Process Name:"<< pe32.szExeFile << "  " << "ProcessID:" << pe32.th32ProcessID << endl;
        bResult = Process32Next(hProcessSnap, &pe32);

    }
    CloseHandle(hProcessSnap);
}

希望对您有所帮助!