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DnsQueryEx (dnsapi)
.
Provides a more customisable query than DNSQuery - uses an Async callback
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
public class DNSQueryer
{
private const int DnsRecordsNoInfo = 9501;
private const int DnsRequestPending = 9506;
private const int DnsAddrMaxSockaddrLength = 32;
private const int DNSQueryCancelSize = 32;
private const short DNSPort = 53;
private const short AFInet = 2;
private const short AFInet16 = 23;
private const int IpAddressV6LengthBytes = 16;
private const int IpAddressV4LengthBytes = 4;
private const uint DnsQueryRequestVersion1 = 1;
public static IDictionary<string, object>[] QueryDNSForRecordTypeSpecificNameServers(string domainName, IPAddress[] dnsServers, DnsRecordTypes recordType)
{
if (dnsServers == null || dnsServers.Length == 0)
{
throw new Exception("At least one DNS Server must be provided to do the query");
}
IntPtr dnsRequest, addrRequestBuffer, contextBuffer;
StringBuilder builder = new StringBuilder();
foreach (IPAddress dnsServer in dnsServers)
{
builder.Append("," + dnsServer.ToString());
}
QueryCompletionContext context = new QueryCompletionContext();
context.eventHandle = new EventWaitHandle(false, EventResetMode.ManualReset);
context.requestType = recordType;
context.resultCode = Marshal.AllocHGlobal(Marshal.SizeOf(typeof(int)));
IntPtr dnsRequest, addrRequestBuffer, contextBuffer;
List<IDictionary<string, object>> dnsRecords = new List<IDictionary<string, object>>();
QueryCompletionContext context = new QueryCompletionContext();
context.eventHandle = new EventWaitHandle(false, EventResetMode.ManualReset);
context.requestType = recordType;
context.resultCode = Marshal.AllocHGlobal(Marshal.SizeOf(typeof(int)));
MakeDnsRequest(domainName, dnsServers, context, out dnsRequest, out addrRequestBuffer, out contextBuffer);
context.dnsRecords = GCHandle.ToIntPtr(handle);
DNSQueryResult queryResult = new DNSQueryResult();
queryResult.Version = DnsQueryRequestVersion1;
MakeDnsRequest(domainName, dnsServers, context, out dnsRequest, out addrRequestBuffer, out contextBuffer);
IntPtr result = Marshal.AllocHGlobal(Marshal.SizeOf(typeof(DNSQueryResult)));
Marshal.StructureToPtr(queryResult, result, false);
DNSQueryResult queryResult = new DNSQueryResult();
queryResult.Version = DnsQueryRequestVersion1;
if (queryResult.QueryStatus != 0)
{
if (queryResult.QueryRecords != IntPtr.Zero)
{
DnsRecordListFree(queryResult.QueryRecords, DNS_FREE_TYPE.DnsFreeRecordList);
Marshal.FreeHGlobal(sockAddrv6InPtr);
}
else
{
throw new Exception(string.Format("Address family {0} not supported", addr.AddressFamily.ToString()));
}
record = Marshal.PtrToStructure(record.Value.Next, typeof(DNS_RECORD)) as DNS_RECORD?;
if (queryResult.QueryRecords != IntPtr.Zero)
{
DnsRecordListFree(queryResult.QueryRecords, DNS_FREE_TYPE.DnsFreeRecordList);
}
[DllImport("dnsapi", SetLastError = true)]
private static extern int DnsCancelQuery(IntPtr cancelHandle);
case (ushort)DnsRecordTypes.DNS_TYPE_TXT:
{
IntPtr stringsCursor = record.Value.Data.TXT.StringArray;
[StructLayout(LayoutKind.Sequential)]
private struct QueryCompletionContext
{
public DnsRecordTypes requestType;
public EventWaitHandle eventHandle;
public IntPtr dnsRecords;
public IntPtr resultCode;
}
StringBuilder valuesBuffer = new StringBuilder();
[StructLayout(LayoutKind.Sequential)]
private struct DNS_QUERY_REQUEST
{
public uint Version;
[MarshalAs(UnmanagedType.LPWStr)]
public string QueryName;
public ushort QueryType;
public ulong QueryOptions;
public IntPtr DnsServerList;
public uint InterfaceIndex;
public IntPtr QueryCompletionCallback;
public IntPtr QueryContext;
}
for (uint i = 0; i < record.Value.Data.TXT.StringCount; i++)
{
IntPtr txtString = Marshal.ReadIntPtr(stringsCursor);
[StructLayout(LayoutKind.Sequential)]
private struct DNS_ADDR_ARRAY
{
public uint MaxCount;
public uint AddrCount;
public uint Tag;
public ushort Family;
public ushort WordReserved;
public uint Flags;
public uint MatchFlag;
public uint Reserved1;
public uint Reserved2;
//// the array of DNS_ADDR follows this
}
string value = Marshal.PtrToStringUni(stringsCursor);
[StructLayout(LayoutKind.Sequential)]
private struct DNSQueryResult
{
public uint Version;
public int QueryStatus;
public ulong QueryOptions;
public IntPtr QueryRecords;
public IntPtr Reserved;
}
IDictionary<string, object> txtRecord = new Dictionary<string, object>();
txtRecord.Add("Type", "TXT");
txtRecord.Add("Name", recordName);
txtRecord.Add("Value", value);
records.Add(txtRecord);
[StructLayout(LayoutKind.Sequential)]
private struct DNS_RECORD
{
public IntPtr Next;
public IntPtr Name;
public ushort Type;
public ushort DataLength;
public FlagsUnion Flags;
public uint TimeToLive;
public uint Reserved;
public DataUnion Data;
}
valuesBuffer.Append(";" + value);
[StructLayout(LayoutKind.Explicit)]
private struct FlagsUnion
{
[FieldOffset(0)]
public uint DW;
[FieldOffset(0)]
public DNS_RECORD_FLAGS S;
}
stringsCursor += Marshal.SizeOf(typeof(IntPtr));
}
[StructLayout(LayoutKind.Sequential)]
private struct DNS_AAAA_DATA
{
public uint Ip6Address0;
public uint Ip6Address1;
public uint Ip6Address2;
public uint Ip6Address3;
}
[DllImport("dnsapi", SetLastError = true)]
private static extern int DnsCancelQuery(IntPtr cancelHandle);
[StructLayout(LayoutKind.Sequential)]
private struct DNS_SRV_DATA
private struct QueryCompletionContext
{
public IntPtr NameTarget;
public ushort Priority;
public ushort Weight;
public ushort Port;
public ushort Pad;
public DnsRecordTypes requestType;
public EventWaitHandle eventHandle;
public IntPtr dnsRecords;
public IntPtr resultCode;
}
public DNS_ADDR()
{
this.maxSa = new byte[DnsAddrMaxSockaddrLength];
this.dnsAddrUserDword = new uint[8];
}
public byte[] MaxSa
{
get
{
return this.maxSa;
}
}
public uint Version;
[MarshalAs(UnmanagedType.LPWStr)]
public string QueryName;
public ushort QueryType;
public ulong QueryOptions;
public IntPtr DnsServerList;
public uint InterfaceIndex;
public IntPtr QueryCompletionCallback;
public IntPtr QueryContext;
}
[StructLayout(LayoutKind.Sequential)]
private class SockAddrIn
private struct DNS_ADDR_ARRAY
{
private short sinFamily;
private ushort sinPort;
[MarshalAs(UnmanagedType.ByValArray, SizeConst = IpAddressV4LengthBytes)]
private byte[] sinAddr;
[MarshalAs(UnmanagedType.ByValArray, SizeConst = 8)]
private byte[] sinZero;
public uint MaxCount;
public uint AddrCount;
public uint Tag;
public ushort Family;
public ushort WordReserved;
public uint Flags;
public uint MatchFlag;
public uint Reserved1;
public uint Reserved2;
//// the array of DNS_ADDR follows this
}
public SockAddrIn()
{
this.sinFamily = 0;
this.sinPort = 0;
this.sinAddr = new byte[IpAddressV4LengthBytes];
this.sinZero = new byte[8];
}
[StructLayout(LayoutKind.Sequential)]
private struct DNSQueryResult
{
public uint Version;
public int QueryStatus;
public ulong QueryOptions;
public IntPtr QueryRecords;
public IntPtr Reserved;
}
public short SinFamily
{
get
{
return this.sinFamily;
}
[StructLayout(LayoutKind.Sequential)]
private struct DNS_RECORD
{
public IntPtr Next;
public IntPtr Name;
public ushort Type;
public ushort DataLength;
public FlagsUnion Flags;
public uint TimeToLive;
public uint Reserved;
public DataUnion Data;
}
set
{
this.sinFamily = value;
}
}
[StructLayout(LayoutKind.Explicit)]
private struct FlagsUnion
{
[FieldOffset(0)]
public uint DW;
[FieldOffset(0)]
public DNS_RECORD_FLAGS S;
}
public ushort SinPort
{
get
{
return this.sinPort;
}
set
{
this.sinPort = value;
}
}
public byte[] SinAddr
{
get
{
return this.sinAddr;
}
}
}
public byte[] Sin6Addr
public uint Reserved
{
get
{
return this.sin6Addr;
}
get { return (this.Data >> 8) & 0xFFFFFFu; }
set { this.Data = (this.Data & ~(0xFFFFFFu << 8)) | (value & 0xFFFFFFu) << 8; }
}
public ulong Sin6ScopeId
{
get
{
return this.sin6ScopeId;
}
set
{
this.sin6ScopeId = value;
}
}
}
}
[StructLayout(LayoutKind.Explicit)]
private struct DataUnion
{
[FieldOffset(0)]
public DNS_A_DATA A;
[FieldOffset(0)]
public DNS_PTR_DATA PTR, NS, CNAME;
[FieldOffset(0)]
public DNS_MX_DATA MX;
[FieldOffset(0)]
public DNS_TXT_DATA TXT;
[FieldOffset(0)]
public DNS_AAAA_DATA AAAA;
[FieldOffset(0)]
public DNS_SRV_DATA SRV;
}
[StructLayout(LayoutKind.Sequential)]
private struct DNS_A_DATA
{
public uint IpAddress;
}
[StructLayout(LayoutKind.Sequential)]
private struct DNS_PTR_DATA
{
public IntPtr NameHost;
}
[StructLayout(LayoutKind.Sequential)]
private struct DNS_MX_DATA
{
public IntPtr NameExchange;
public ushort Preference;
public ushort Pad;
}
[StructLayout(LayoutKind.Sequential)]
private struct DNS_TXT_DATA
{
public uint StringCount;
public IntPtr StringArray;
}
[StructLayout(LayoutKind.Sequential)]
private struct DNS_AAAA_DATA
{
public uint Ip6Address0;
public uint Ip6Address1;
public uint Ip6Address2;
public uint Ip6Address3;
}
[StructLayout(LayoutKind.Sequential)]
private struct DNS_SRV_DATA
{
public IntPtr NameTarget;
public ushort Priority;
public ushort Weight;
public ushort Port;
public ushort Pad;
}
public SockAddrIn6()
{
this.sin6Family = AFInet;
this.sin6Port = 0;
this.sin6Addr = new byte[IpAddressV6LengthBytes];
this.sin6ScopeId = 0;
}
public short Sin6Family
{
get
{
return this.sin6Family;
}
set
{
this.sin6Family = value;
}
}
public ushort Sin6Port
{
get
{
return this.sin6Port;
}
set
{
this.sin6Port = value;
}
}
public ulong Sin6FlowInfo
{
get
{
return this.sin6FlowInfo;
}
set
{
this.sin6FlowInfo = value;
}
}
public byte[] Sin6Addr
{
get
{
return this.sin6Addr;
}
}
public ulong Sin6ScopeId
{
get
{
return this.sin6ScopeId;
}
set
{
this.sin6ScopeId = value;
}
}
}
}
DNSQueryEx (built off DNSQuery page)
7/5/2016 12:30:57 AM - -213.171.217.185
DNSQueryEx (built off DNSQuery page)
7/18/2016 3:46:41 PM - -95.93.140.43
DNSQueryEx (built off DNSQuery page)
7/18/2016 3:46:41 PM - -95.93.140.43
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