Win32 API 日本語リファレンス
ホーム › NetworkManagement.Dns › DNS_MESSAGE_BUFFER

DNS_MESSAGE_BUFFER

構造体
📘 Microsoft Learn (日本語) · English
サイズx64: 13 バイト / x86: 13 バイト

サイズ=各フィールドのバイト数(x64/x86 で異なる場合は x64/x86 と併記)。x64/x86 列=フィールドのバイトオフセット(HSPで dupptr / lpoke / wpoke 等に使用)。

フィールド

フィールド型サイズx64x86説明
MessageHeadDNS_HEADER12+0+0DNSメッセージのヘッダ部を保持するDNS_HEADER構造体。
MessageBodyCHAR1+12+12ヘッダに続くメッセージ本体の生バイト列を保持する可変長配列の先頭。

各言語での定義

#include <windows.h>

// DNS_HEADER  (x64 12 / x86 12 バイト)
#pragma pack(push, 1)
typedef struct DNS_HEADER {
    WORD Xid;
    BYTE _bitfield1;
    BYTE _bitfield2;
    WORD QuestionCount;
    WORD AnswerCount;
    WORD NameServerCount;
    WORD AdditionalCount;
} DNS_HEADER;
#pragma pack(pop)

// DNS_MESSAGE_BUFFER  (x64 13 / x86 13 バイト)
typedef struct DNS_MESSAGE_BUFFER {
    DNS_HEADER MessageHead;
    CHAR MessageBody[1];
} DNS_MESSAGE_BUFFER;
using System;
using System.Runtime.InteropServices;

[StructLayout(LayoutKind.Sequential, Pack = 1, CharSet = CharSet.Unicode)]
public struct DNS_HEADER
{
    public ushort Xid;
    public byte _bitfield1;
    public byte _bitfield2;
    public ushort QuestionCount;
    public ushort AnswerCount;
    public ushort NameServerCount;
    public ushort AdditionalCount;
}

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
public struct DNS_MESSAGE_BUFFER
{
    public DNS_HEADER MessageHead;
    [MarshalAs(UnmanagedType.ByValArray, SizeConst = 1)] public sbyte[] MessageBody;
}
Imports System.Runtime.InteropServices

<StructLayout(LayoutKind.Sequential, Pack:=1, CharSet:=CharSet.Unicode)>
Public Structure DNS_HEADER
    Public Xid As UShort
    Public _bitfield1 As Byte
    Public _bitfield2 As Byte
    Public QuestionCount As UShort
    Public AnswerCount As UShort
    Public NameServerCount As UShort
    Public AdditionalCount As UShort
End Structure

<StructLayout(LayoutKind.Sequential, CharSet:=CharSet.Unicode)>
Public Structure DNS_MESSAGE_BUFFER
    Public MessageHead As DNS_HEADER
    <MarshalAs(UnmanagedType.ByValArray, SizeConst:=1)> Public MessageBody() As SByte
End Structure
import ctypes
from ctypes import wintypes

class DNS_HEADER(ctypes.Structure):
    _pack_ = 1
    _fields_ = [
        ("Xid", ctypes.c_ushort),
        ("_bitfield1", ctypes.c_ubyte),
        ("_bitfield2", ctypes.c_ubyte),
        ("QuestionCount", ctypes.c_ushort),
        ("AnswerCount", ctypes.c_ushort),
        ("NameServerCount", ctypes.c_ushort),
        ("AdditionalCount", ctypes.c_ushort),
    ]

class DNS_MESSAGE_BUFFER(ctypes.Structure):
    _fields_ = [
        ("MessageHead", DNS_HEADER),
        ("MessageBody", ctypes.c_byte * 1),
    ]
#[repr(C, packed(1))]
pub struct DNS_HEADER {
    pub Xid: u16,
    pub _bitfield1: u8,
    pub _bitfield2: u8,
    pub QuestionCount: u16,
    pub AnswerCount: u16,
    pub NameServerCount: u16,
    pub AdditionalCount: u16,
}

#[repr(C)]
pub struct DNS_MESSAGE_BUFFER {
    pub MessageHead: DNS_HEADER,
    pub MessageBody: [i8; 1],
}
import "golang.org/x/sys/windows"

type DNS_HEADER struct {
	Xid uint16
	_bitfield1 byte
	_bitfield2 byte
	QuestionCount uint16
	AnswerCount uint16
	NameServerCount uint16
	AdditionalCount uint16
}

type DNS_MESSAGE_BUFFER struct {
	MessageHead DNS_HEADER
	MessageBody [1]int8
}
type
  DNS_HEADER = packed record
    Xid: Word;
    _bitfield1: Byte;
    _bitfield2: Byte;
    QuestionCount: Word;
    AnswerCount: Word;
    NameServerCount: Word;
    AdditionalCount: Word;
  end;

  DNS_MESSAGE_BUFFER = record
    MessageHead: DNS_HEADER;
    MessageBody: array[0..0] of Shortint;
  end;
const DNS_HEADER = extern struct {
    Xid: u16,
    _bitfield1: u8,
    _bitfield2: u8,
    QuestionCount: u16,
    AnswerCount: u16,
    NameServerCount: u16,
    AdditionalCount: u16,
};

const DNS_MESSAGE_BUFFER = extern struct {
    MessageHead: DNS_HEADER,
    MessageBody: [1]i8,
};
type
  DNS_HEADER {.packed.} = object
    Xid: uint16
    _bitfield1: uint8
    _bitfield2: uint8
    QuestionCount: uint16
    AnswerCount: uint16
    NameServerCount: uint16
    AdditionalCount: uint16

  DNS_MESSAGE_BUFFER {.bycopy.} = object
    MessageHead: DNS_HEADER
    MessageBody: array[1, int8]
align(1)
struct DNS_HEADER
{
    ushort Xid;
    ubyte _bitfield1;
    ubyte _bitfield2;
    ushort QuestionCount;
    ushort AnswerCount;
    ushort NameServerCount;
    ushort AdditionalCount;
}

struct DNS_MESSAGE_BUFFER
{
    DNS_HEADER MessageHead;
    byte[1] MessageBody;
}

HSP用 定義

HSP3.7/3.8 は構造体機能が無いため4byte整数配列(dim)+peek/poke で操作(32/64bitでサイズ・位置が異なる場合はタブで分割)。IronHSP は NSTRUCT(#defstruct/stdim/->)で32/64bit共通。

; HSP3.7/3.8 は構造体機能が無いため、4byte整数の配列変数で操作します。(x64 レイアウト)
; DNS_MESSAGE_BUFFER サイズ: 13 バイト(x64)
dim st, 4    ; 4byte整数×4(構造体サイズ 13 / 4 切り上げ)
; MessageHead : DNS_HEADER (+0, 12byte)  varptr(st)+0 を基点に操作(12byte:入れ子/配列)
; MessageBody : CHAR (+12, 1byte)  varptr(st)+12 を基点に操作(1byte:入れ子/配列)
; ※4byte境界の整数は添字 st.N(N=オフセット/4)で読み書き可。それ以外は peek/poke 系を使用。
; IronHSP は NSTRUCT(構造体)をサポート。32bit/64bit どちらでも同じコードで動作します。
; ※GUID・入れ子構造体はデフォルト型でないため、依存する #defstruct を先に定義(下記に同梱)。
#defstruct global DNS_HEADER, pack=1
    #field short Xid
    #field byte _bitfield1
    #field byte _bitfield2
    #field short QuestionCount
    #field short AnswerCount
    #field short NameServerCount
    #field short AdditionalCount
#endstruct

#defstruct global DNS_MESSAGE_BUFFER
    #field DNS_HEADER MessageHead
    #field byte MessageBody 1
#endstruct

stdim st, DNS_MESSAGE_BUFFER        ; NSTRUCT 変数を確保