DNS_RECORDW structure (windns.h)

Article
07/27/2022

The DNS_RECORD structure stores a DNS resource record (RR).

Syntax

typedef struct _DnsRecordW {
  struct _DnsRecordW *pNext;
  PWSTR              pName;
  WORD               wType;
  WORD               wDataLength;
  union {
    DWORD            DW;
    DNS_RECORD_FLAGS S;
  } Flags;
  DWORD              dwTtl;
  DWORD              dwReserved;
  union {
    DNS_A_DATA          A;
    DNS_SOA_DATAW       SOA;
    DNS_SOA_DATAW       Soa;
    DNS_PTR_DATAW       PTR;
    DNS_PTR_DATAW       Ptr;
    DNS_PTR_DATAW       NS;
    DNS_PTR_DATAW       Ns;
    DNS_PTR_DATAW       CNAME;
    DNS_PTR_DATAW       Cname;
    DNS_PTR_DATAW       DNAME;
    DNS_PTR_DATAW       Dname;
    DNS_PTR_DATAW       MB;
    DNS_PTR_DATAW       Mb;
    DNS_PTR_DATAW       MD;
    DNS_PTR_DATAW       Md;
    DNS_PTR_DATAW       MF;
    DNS_PTR_DATAW       Mf;
    DNS_PTR_DATAW       MG;
    DNS_PTR_DATAW       Mg;
    DNS_PTR_DATAW       MR;
    DNS_PTR_DATAW       Mr;
    DNS_MINFO_DATAW     MINFO;
    DNS_MINFO_DATAW     Minfo;
    DNS_MINFO_DATAW     RP;
    DNS_MINFO_DATAW     Rp;
    DNS_MX_DATAW        MX;
    DNS_MX_DATAW        Mx;
    DNS_MX_DATAW        AFSDB;
    DNS_MX_DATAW        Afsdb;
    DNS_MX_DATAW        RT;
    DNS_MX_DATAW        Rt;
    DNS_TXT_DATAW       HINFO;
    DNS_TXT_DATAW       Hinfo;
    DNS_TXT_DATAW       ISDN;
    DNS_TXT_DATAW       Isdn;
    DNS_TXT_DATAW       TXT;
    DNS_TXT_DATAW       Txt;
    DNS_TXT_DATAW       X25;
    DNS_NULL_DATA       Null;
    DNS_WKS_DATA        WKS;
    DNS_WKS_DATA        Wks;
    DNS_AAAA_DATA       AAAA;
    DNS_KEY_DATA        KEY;
    DNS_KEY_DATA        Key;
    DNS_SIG_DATAW       SIG;
    DNS_SIG_DATAW       Sig;
    DNS_ATMA_DATA       ATMA;
    DNS_ATMA_DATA       Atma;
    DNS_NXT_DATAW       NXT;
    DNS_NXT_DATAW       Nxt;
    DNS_SRV_DATAW       SRV;
    DNS_SRV_DATAW       Srv;
    DNS_NAPTR_DATAW     NAPTR;
    DNS_NAPTR_DATAW     Naptr;
    DNS_OPT_DATA        OPT;
    DNS_OPT_DATA        Opt;
    DNS_DS_DATA         DS;
    DNS_DS_DATA         Ds;
    DNS_RRSIG_DATAW     RRSIG;
    DNS_RRSIG_DATAW     Rrsig;
    DNS_NSEC_DATAW      NSEC;
    DNS_NSEC_DATAW      Nsec;
    DNS_DNSKEY_DATA     DNSKEY;
    DNS_DNSKEY_DATA     Dnskey;
    DNS_TKEY_DATAW      TKEY;
    DNS_TKEY_DATAW      Tkey;
    DNS_TSIG_DATAW      TSIG;
    DNS_TSIG_DATAW      Tsig;
    DNS_WINS_DATA       WINS;
    DNS_WINS_DATA       Wins;
    DNS_WINSR_DATAW     WINSR;
    DNS_WINSR_DATAW     WinsR;
    DNS_WINSR_DATAW     NBSTAT;
    DNS_WINSR_DATAW     Nbstat;
    DNS_DHCID_DATA      DHCID;
    DNS_NSEC3_DATA      NSEC3;
    DNS_NSEC3_DATA      Nsec3;
    DNS_NSEC3PARAM_DATA NSEC3PARAM;
    DNS_NSEC3PARAM_DATA Nsec3Param;
    DNS_TLSA_DATA       TLSA;
    DNS_TLSA_DATA       Tlsa;
    DNS_SVCB_DATA       SVCB;
    DNS_SVCB_DATA       Svcb;
    DNS_UNKNOWN_DATA    UNKNOWN;
    DNS_UNKNOWN_DATA    Unknown;
    PBYTE               pDataPtr;
  } Data;
} DNS_RECORDW, *PDNS_RECORDW;

Members

pNext

A pointer to the next DNS_RECORD structure.

pName

A pointer to a string that represents the domain name of the record set. This must be in the string format that corresponds to the function called, such as ANSI, Unicode, or UTF8.

wType

A value that represents the RR DNS Record Type. wType determines the format of Data. For example, if the value of wType is DNS_TYPE_A, the data type of Data is DNS_A_DATA.

wDataLength

The length, in bytes, of Data. For fixed-length data types, this value is the size of the corresponding data type, such as sizeof(DNS_A_DATA). For the non-fixed data types, use one of the following macros to determine the length of the data:

C++
#include <windows.h> #define DNS_NULL_RECORD_LENGTH(ByteCount) (sizeof(DWORD) + (ByteCount)) #define DNS_WKS_RECORD_LENGTH(ByteCount) (sizeof(DNS_WKS_DATA) + (ByteCount-1)) #define DNS_WINS_RECORD_LENGTH(IpCount) (sizeof(DNS_WINS_DATA) + ((IpCount-1) * sizeof(IP_ADDRESS))) #define DNS_TEXT_RECORD_LENGTH(StringCount) (sizeof(DWORD) + ((StringCount) * sizeof(PCHAR)))

C++

#include <windows.h>
#define DNS_NULL_RECORD_LENGTH(ByteCount) (sizeof(DWORD) + (ByteCount))
#define DNS_WKS_RECORD_LENGTH(ByteCount) (sizeof(DNS_WKS_DATA) + (ByteCount-1))
#define DNS_WINS_RECORD_LENGTH(IpCount) (sizeof(DNS_WINS_DATA) + ((IpCount-1) * sizeof(IP_ADDRESS)))
#define DNS_TEXT_RECORD_LENGTH(StringCount) (sizeof(DWORD) + ((StringCount) * sizeof(PCHAR)))

Flags

Flags.DW

A value that contains a bitmap of DNS Record Flags.

Flags.S

A set of flags in the form of a DNS_RECORD_FLAGS structure.

dwTtl

The DNS RR's Time To Live value (TTL), in seconds.

dwReserved

Reserved. Do not use.

Data

The DNS RR data type is determined by wType and is one of the following members:

SOA, Soa

The RR data type is DNS_SOA_DATA. The value of wType is DNS_TYPE_SOA.

PTR, Ptr, NS, Ns, CNAME, Cname, DNAME, Dname, MB, Mb, MD, Md, MF, Mf, MG, Mg, MR, Mr

The RR data type is DNS_PTR_DATA. The value of wType is DNS_TYPE_PTR.

MINFO, Minfo, RP, Rp

The RR data type is DNS_MINFO_DATA. The value of wType is DNS_TYPE_MINFO.

MX, Mx, AFSDB, Afsdb, RT, Rt

The RR data type is DNS_MX_DATA. The value of wType is DNS_TYPE_MX.

HINFO, Hinfo, ISDN, Isdn, TXT, Txt, X25

The RR data type is DNS_TXT_DATA. The value of wType is DNS_TYPE_TEXT.

WKS, Wks

The RR data type is DNS_WKS_DATA. The value of wType is DNS_TYPE_WKS.

KEY, Key

The RR data type is DNS_KEY_DATA. The value of wType is DNS_TYPE_KEY.

SIG, Sig

The RR data type is DNS_SIG_DATA. The value of wType is DNS_TYPE_SIG.

ATMA, Atma

The RR data type is DNS_ATMA_DATA. The value of wType is DNS_TYPE_ATMA.

NXT, Nxt

The RR data type is DNS_NXT_DATA. The value of wType is DNS_TYPE_NXT.

SRV, Srv

The RR data type is DNS_SRV_DATA. The value of wType is DNS_TYPE_SRV.

NAPTR, Naptr

The RR data type is DNS_NAPTR_DATA. The value of wType is DNS_TYPE_NAPTR.

OPT, Opt

Windows 7 or later: The RR data type is DNS_OPT_DATA. The value of wType is DNS_TYPE_OPT.

DS, Ds

Windows 7 or later: The RR data type is DNS_DS_DATA. The value of wType is DNS_TYPE_DS.

RRSIG, Rrsig

Windows 7 or later: The RR data type is DNS_RRSIG_DATA. The value of wType is DNS_TYPE_RRSIG.

NSEC, Nsec

Windows 7 or later: The RR data type is DNS_NSEC_DATA. The value of wType is DNS_TYPE_NSEC.

DNSKEY, Dnskey

Windows 7 or later: The RR data type is DNS_DNSKEY_DATA. The value of wType is DNS_TYPE_DNSKEY.

TKEY, Tkey

The RR data type is DNS_TKEY_DATA. The value of wType is DNS_TYPE_TKEY.

TSIG, Tsig

The RR data type is DNS_TSIG_DATA. The value of wType is DNS_TYPE_TSIG.

WINS, Wins

The RR data type is DNS_WINS_DATA. The value of wType is DNS_TYPE_WINS.

WINSR, WinsR, NBSTAT, Nbstat

The RR data type is DNS_WINSR_DATA. The value of wType is DNS_TYPE_WINSR.

Data.A

The RR data type is DNS_A_DATA. The value of wType is DNS_TYPE_A.

Data.SOA

Data.Soa

Data.PTR

Data.Ptr

Data.NS

Data.Ns

Data.CNAME

Data.Cname

Data.DNAME

Data.Dname

Data.MB

Data.Mb

Data.MD

Data.Md

Data.MF

Data.Mf

Data.MG

Data.Mg

Data.MR

Data.Mr

Data.MINFO

Data.Minfo

Data.RP

Data.Rp

Data.MX

Data.Mx

Data.AFSDB

Data.Afsdb

Data.RT

Data.Rt

Data.HINFO

Data.Hinfo

Data.ISDN

Data.Isdn

Data.TXT

Data.Txt

Data.X25

Data.Null

The RR data type is DNS_NULL_DATA. The value of wType is DNS_TYPE_NULL.

Data.WKS

Data.Wks

Data.AAAA

The RR data type is DNS_AAAA_DATA. The value of wType is DNS_TYPE_AAAA.

Data.KEY

Data.Key

Data.SIG

Data.Sig

Data.ATMA

Data.Atma

Data.NXT

Data.Nxt

Data.SRV

Data.Srv

Data.NAPTR

Data.Naptr

Data.OPT

Data.Opt

Data.DS

Data.Ds

Data.RRSIG

Data.Rrsig

Data.NSEC

Data.Nsec

Data.DNSKEY

Data.Dnskey

Data.TKEY

Data.Tkey

Data.TSIG

Data.Tsig

Data.WINS

Data.Wins

Data.WINSR

Data.WinsR

Data.NBSTAT

Data.Nbstat

Data.DHCID

Windows 7 or later: The RR data type is DNS_DHCID_DATA. The value of wType is DNS_TYPE_DHCID.

Data.NSEC3

Data.Nsec3

Data.NSEC3PARAM

Data.Nsec3Param

Data.TLSA

Data.Tlsa

Data.SVCB

Data.Svcb

Data.UNKNOWN

Data.Unknown

Data.pDataPtr

Remarks

When building a DNS_RECORD list as an input argument for the various DNS update routines found in the DNS API, all flags in the DNS_RECORD structure should be set to zero.

Note

The windns.h header defines DNS_RECORD as an alias which automatically selects the ANSI or Unicode version of this function based on the definition of the UNICODE preprocessor constant. Mixing usage of the encoding-neutral alias with code that not encoding-neutral can lead to mismatches that result in compilation or runtime errors. For more information, see Conventions for Function Prototypes.

Requirements

Requirement	Value
Minimum supported client	Windows 2000 Professional [desktop apps only]
Minimum supported server	Windows 2000 Server [desktop apps only]
Header	windns.h