DnsApi simple exploration (2) DNS

As mentioned above, the DnsQueryEx () request requires three parameters. DNS_QUERY_REQUEST is the first parameter used for request information, such as the DNS server to be requested and the domain name to be requested. the DNS_QUERY_REQUESTstructureDNS_QUERY_REQUEST structure contains the parameter language used by DnsQueryEx () for DNS requests.

As mentioned above, the DnsQueryEx () request requires three parameters. DNS_QUERY_REQUEST is the first parameter used for request information, such as the DNS server to be requested and the domain name to be requested. DNS_QUERY_REQUEST structure the DNS_QUERY_REQUEST structure contains the parameter language used by DnsQueryEx () for DNS requests.

As mentioned above, the DnsQueryEx () request requires three parameters. DNS_QUERY_REQUEST is the first parameter used for request information, such as the DNS server to be requested and the domain name to be requested.

DNS_QUERY_REQUEST structure

The DNS_QUERY_REQUEST structure contains the parameters used by DnsQueryEx () for DNS requests.

Syntax

typedef struct _DNS_QUERY_REQUEST {       ULONG                         Version;       PCWSTR                        QueryName;       WORD                          QueryType;       ULONG64                       QueryOptions;       PDNS_ADDR_ARRAY               pDnsServerList;       ULONG                         InterfaceIndex;       PDNS_QUERY_COMPLETION_ROUTINE pQueryCompletionCallback;       PVOID                         pQueryContext;} DNS_QUERY_REQUEST, *PDNS_QUERY_REQUEST;

Member

Version

The structure version number must be one of the following:

DNS_QUERY_REQUEST_VERSION1(1)

QueryName

A pointer to the string of the DNS name to be queried,

Note:IfQueryNameIf it is null, use the local DNS for query.

QueryType

Resource Record (RR)DNS_Record_TypeIndicates whether the request is sent.

QueryTypeDecidedDNS_QUERY_RESULTReturnedPQueryRecordData format.

For example, ifWTypeYesDNS_TYPE_A,PQueryRecordsThe data format isDNS_A_DATA.

QueryOptions

ContainsDNS_Query_OptionsBitmap ).

DNS_Query_OptionsOptions can be combined, and all options OverwriteDNS_QUERY_STANDARD

PDnsServerList

One pointDNS_ADDR_ARRAYContainsDNS_ServersList.

InterfaceIndex

Interface index. If the InterfaceIndex value is 0, all interfaces will be considered.

PQueryCompletionCallback

PointDNS_QUERY_COMPLETION_ROUTINEPointer to the callback function,DNS_QUERY_COMPLETION_ROUTINEReturns the asynchronous query result.

Note:If the value isNULL, DnsQueryEx isSynchronizationMechanism.

PQueryContext

Pointer to user-defined data.

Note:

Some definitions, suchQueryTypeAnd so on,Please refer to the official website of Microsoft.