public DnsQuestion(DnsString query, QueryType questionType, QueryClass questionClass)
{
if (query == null)
{
throw new ArgumentNullException(nameof(query));
}
QueryName = query;
QuestionType = questionType;
QuestionClass = questionClass;
}
// only used by the DnsQuestion as we don't expect any escaped chars in the actual query posted to and send back from the DNS Server (not supported).
public DnsString ReadQuestionQueryString()
{
var result = new StringBuilder();
foreach (var labelArray in ReadLabels())
{
var label = Encoding.UTF8.GetString(labelArray.Array, labelArray.Offset, labelArray.Count);
result.Append(label);
result.Append(".");
}
string value = result.ToString();
return(DnsString.FromResponseQueryString(value));
}
private static IPHostEntry GetHostEntryProcessResult(DnsString hostString, DnsResourceRecord[] allRecords)
{
var addressRecords = allRecords
.OfType <AddressRecord>()
.Select(p => new
{
Address = p.Address,
Alias = DnsString.FromResponseQueryString(p.DomainName)
})
.ToArray();
var hostEntry = new IPHostEntry()
{
Aliases = new string[0],
AddressList = addressRecords
.Select(p => p.Address)
.ToArray()
};
if (addressRecords.Length > 1)
{
if (addressRecords.Any(p => !p.Alias.Equals(hostString)))
{
hostEntry.Aliases = addressRecords
.Select(p => p.Alias.ToString())
.Select(p => p.Substring(0, p.Length - 1))
.Distinct()
.ToArray();
}
}
else if (addressRecords.Length == 1)
{
if (allRecords.Any(p => !DnsString.FromResponseQueryString(p.DomainName).Equals(hostString)))
{
hostEntry.Aliases = allRecords
.Select(p => p.DomainName.ToString())
.Select(p => p.Substring(0, p.Length - 1))
.Distinct()
.ToArray();
}
}
hostEntry.HostName = hostString.Value.Substring(0, hostString.Value.Length - 1);
return(hostEntry);
}
private static IPHostEntry GetHostEntryFromName(IDnsQuery query, string hostName)
{
if (string.IsNullOrWhiteSpace(hostName))
{
throw new ArgumentNullException(nameof(hostName));
}
var hostString = DnsString.FromResponseQueryString(hostName);
var ipv4Result = query.Query(hostString, QueryType.A);
var ipv6Result = query.Query(hostString, QueryType.AAAA);
var allRecords = ipv4Result
.Answers.Concat(ipv6Result.Answers)
.ToArray();
return(GetHostEntryProcessResult(hostString, allRecords));
}
private static async Task <IPHostEntry> GetHostEntryFromNameAsync(IDnsQuery query, string hostName)
{
if (string.IsNullOrWhiteSpace(hostName))
{
throw new ArgumentNullException(nameof(hostName));
}
var hostString = DnsString.FromResponseQueryString(hostName);
var ipv4Result = query.QueryAsync(hostString, QueryType.A);
var ipv6Result = query.QueryAsync(hostString, QueryType.AAAA);
await Task.WhenAll(ipv4Result, ipv6Result).ConfigureAwait(false);
var allRecords = ipv4Result.Result
.Answers.Concat(ipv6Result.Result.Answers)
.ToArray();
return(GetHostEntryProcessResult(hostString, allRecords));
}
/// <summary>
/// Initializes a new instance of the <see cref="DnsQuestion"/> class.
/// </summary>
/// <param name="query">The query.</param>
/// <param name="questionType">Type of the question.</param>
/// <param name="questionClass">The question class.</param>
/// <exception cref="ArgumentNullException">If <paramref name="query"/> is null.</exception>
public DnsQuestion(DnsString query, PseudoResourceRecordType questionType, QueryClass questionClass)
{
QueryName = query ?? throw new ArgumentNullException(nameof(query));
QuestionType = questionType;
QuestionClass = questionClass;
}
/// <summary>
/// Initializes a new instance of the <see cref="DnsQuestion"/> class.
/// </summary>
/// <param name="query">The query.</param>
/// <param name="questionType">Type of the question.</param>
/// <param name="questionClass">The question class.</param>
/// <exception cref="ArgumentNullException">If <paramref name="query"/> is null.</exception>
public DnsQuestion(string query, PseudoResourceRecordType questionType, QueryClass questionClass)
: this(DnsString.Parse(query), questionType, questionClass)
{
}
/// <summary>
/// Initializes a new instance of the <see cref="DnsQuestion"/> class.
/// </summary>
/// <param name="query">The query.</param>
/// <param name="questionType">Type of the question.</param>
/// <param name="questionClass">The question class.</param>
/// <exception cref="ArgumentNullException">If <paramref name="query"/> is null.</exception>
public DnsQuestion(DnsString query, QueryType questionType, QueryClass questionClass = QueryClass.IN)
{
QueryName = query ?? throw new ArgumentNullException(nameof(query));
QuestionType = questionType;
QuestionClass = questionClass;
}
/// <summary>
/// Initializes a new instance of the <see cref="DnsQuestion"/> class.
/// </summary>
/// <param name="query">The query.</param>
/// <param name="questionType">Type of the question.</param>
/// <param name="questionClass">The question class.</param>
/// <exception cref="ArgumentNullException">If <paramref name="query"/> is null.</exception>
public DnsQuestion(string query, QueryType questionType, QueryClass questionClass = QueryClass.IN)
: this(DnsString.Parse(query), questionType, questionClass)
{
}