c - NtDeviceIoControlFile-获取缓冲区的大小

我正在使用NtDeviceIoControlFile控制代码调用IOCTL_TCP_QUERY_INFORMATION_EX，但是在执行实际调用之前，我需要获取输出缓冲区的大小，以便可以为其分配适当的大小。

这是我的代码：

    TCP_REQUEST_QUERY_INFORMATION_EX TcpRequestQuery;
    IO_STATUS_BLOCK StatusBlock;
    DWORD BufferSize = sizeof(TDIENTITYID) * 4096;

    memset(&TcpRequestQuery, 0, sizeof(TcpRequestQuery));
    TcpRequestQuery.ID.toi_class = 0x100;
    TcpRequestQuery.ID.toi_type = 0x100;
    TcpRequestQuery.ID.toi_id = 0;
    TcpRequestQuery.ID.toi_entity.tei_entity = 0;
    TcpRequestQuery.ID.toi_entity.tei_instance = 0;

    *EntityList = (TDIENTITYID *) GlobalAlloc (GMEM_ZEROINIT, BufferSize);
    NTSTATUS Status = NtDeviceIoControlFile(
        TcpFile, NULL, NULL, NULL, &IOBlock, IOCTL_TCP_QUERY_INFORMATION_EX,
        &TcpQueryInfo, sizeof(TcpQueryInfo), *EntityList, BufferSize);

    if (!NT_SUCCESS(Status))
        return Status;

    BufferSize = StatusBlock.uInformation;

问题是第一次调用NtDeviceIoControlFile返回ERROR_INVALID_PARAMETER (87)。使用SYNCHRONIZE标志设置打开TCP设备对象的句柄。

问题是为什么，在哪里？

最佳答案

#include <tdiinfo.h>
#include <tcpioctl.h>

NTSTATUS QueryTcp()
{
    NTSTATUS status;
#ifndef _WIN64

    struct TCP_REQUEST_QUERY_INFORMATION_EX_WOW
    {
        TDIObjectID     ID;                     // object ID to query.
        ULONG           pad;                    // ! for wow64 only - Context must be aligned on 8 byte in 64bit windows
        uchar           Context[CONTEXT_SIZE];  // multi-request context. Zeroed
    };

    PVOID Wow;
    status = NtQueryInformationProcess(NtCurrentProcess(), ProcessWow64Information, &Wow, sizeof(Wow), 0);
    if (0 > status)
    {
        return status;
    }
#endif

    static const UNICODE_STRING ObjectName = RTL_CONSTANT_STRING(L"\\device\\tcp");
    static const OBJECT_ATTRIBUTES oa = { sizeof(oa), 0, const_cast<PUNICODE_STRING>(&ObjectName), OBJ_CASE_INSENSITIVE };

    HANDLE hFile;
    IO_STATUS_BLOCK iosb;
    status = NtOpenFile(&hFile, SYNCHRONIZE,
        const_cast<POBJECT_ATTRIBUTES>(&oa), &iosb, FILE_SHARE_VALID_FLAGS, FILE_SYNCHRONOUS_IO_NONALERT);

    if (0 <= status)
    {
        PVOID InputBuffer;
        ULONG InputBufferLength;

#ifndef _WIN64
        if (Wow)
        {
            TCP_REQUEST_QUERY_INFORMATION_EX_WOW req = {
                { { GENERIC_ENTITY }, INFO_CLASS_GENERIC, INFO_TYPE_PROVIDER, ENTITY_LIST_ID }
            };

            InputBuffer = &req, InputBufferLength = sizeof(req);
        }
        else
#endif
        {
            TCP_REQUEST_QUERY_INFORMATION_EX req = {
                { { GENERIC_ENTITY }, INFO_CLASS_GENERIC, INFO_TYPE_PROVIDER, ENTITY_LIST_ID }
            };

            InputBuffer = &req, InputBufferLength = sizeof(req);
        }

        union {
            PVOID buf;
            TDIEntityID* pEntity;
        };

        volatile static UCHAR guz;

        PVOID stack = alloca(guz);

        ULONG cbAllocated = 0, cbNeed = 8 * sizeof(TDIEntityID);

        do
        {
            if (cbAllocated < cbNeed)
            {
                cbAllocated = RtlPointerToOffset(buf = alloca(cbNeed - cbAllocated), stack);
            }

            if (0 <= (status = NtDeviceIoControlFile(hFile, 0, 0, 0, &iosb,
                IOCTL_TCP_QUERY_INFORMATION_EX, InputBuffer, InputBufferLength, buf, cbAllocated)))
            {
                if (ULONG n = (ULONG)iosb.Information / sizeof(TDIEntityID))
                {
                    do
                    {
                        DbgPrint("{ %08x, %08x }\n", pEntity->tei_entity, pEntity->tei_instance);
                    } while (pEntity++, --n);
                }
            }

            cbNeed += 8 * sizeof(TDIEntityID);

        } while (status == STATUS_BUFFER_OVERFLOW || status == STATUS_BUFFER_TOO_SMALL);

        NtClose(hFile);
    }

    return status;
}

和输出

{ 00000400, 00000000 }
{ 00000401, 00000000 }
{ 00000301, 00000000 }
{ 00000301, 00000001 }
{ 00000380, 00000000 }
{ 00000380, 00000001 }
{ 00000200, 00000015 }
{ 00000200, 00000014 }
{ 00000200, 00000013 }
{ 00000200, 00000012 }
{ 00000200, 00000011 }
{ 00000200, 00000010 }
{ 00000200, 0000000f }
{ 00000200, 0000000e }
{ 00000200, 0000000d }

然后我们可以从输出数组中获取具体的TDIEntityID，将其复制到TCP_REQUEST_QUERY_INFORMATION_EX并对此实体进行详细请求，如下所述-https://msdn.microsoft.com/en-us/library/bb432313(v=vs.85).aspx

关于c - NtDeviceIoControlFile-获取缓冲区的大小，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/46531833/