/// <summary>
/// Implementation Reference RFC 3658
/// </summary>
/// <param name="buffer"></param>
public DSRecord(DataBuffer buffer, int length)
{
key = buffer.ReadShortInt();
algorithm = buffer.ReadByte();
digestType = buffer.ReadByte();
digest = buffer.ReadBytes(length - 4);
}
public KeyRecord(DataBuffer buffer, int length)
{
flags = buffer.ReadShortInt();
protocol = buffer.ReadByte();
algorithm = buffer.ReadByte();
publicKey = buffer.ReadBytes(length - 4);
}
/// <summary>
/// WKS Record Type Consructor
/// </summary>
/// <param name="buffer"></param>
/// <param name="length"></param>
public WksRecord(DataBuffer buffer, int length)
{
ipAddress = buffer.ReadIPAddress();
protocol = buffer.ReadByte();
services = new Byte[length - 5];
for(int i = 0; i < (length - 5); i++)
services[i] = buffer.ReadByte();
}
/// <summary>
/// Create a DNSEntry record and dispatch to data constructor
/// for thast record type
/// </summary>
/// <param name="buffer"></param>
public DnsEntry(DataBuffer buffer)
{
try
{
domain = buffer.ReadDomainName();
buffer.ReadByte();
recType = (RecordType)buffer.ReadShortInt();
classType = buffer.ReadShortInt();
ttl = buffer.ReadInt();
int length = buffer.ReadByte();
switch (recType)
{
case RecordType.A: data = new ARecord(buffer); break;
case RecordType.NS: data = new NSRecord(buffer); break;
case RecordType.CNAME: data = new CNameRecord(buffer); break;
case RecordType.SOA: data = new SoaRecord(buffer); break;
case RecordType.MB: data = new MBRecord(buffer); break;
case RecordType.MG: data = new MGRecord(buffer); break;
case RecordType.MR: data = new MRRecord(buffer); break;
case RecordType.NULL: data = new NullRecord(buffer, length); break;
case RecordType.WKS: data = new WksRecord(buffer, length); break;
case RecordType.PTR: data = new PtrRecord(buffer); break;
case RecordType.HINFO: data = new HInfoRecord(buffer, length); break;
case RecordType.MINFO: data = new MInfoRecord(buffer); break;
case RecordType.MX: data = new MXRecord(buffer); break;
case RecordType.TXT: data = new TxtRecord(buffer, length); break;
case RecordType.RP: data = new RPRecord(buffer); break;
case RecordType.AFSDB: data = new AfsdbRecord(buffer); break;
case RecordType.X25: data = new X25Record(buffer); break;
case RecordType.ISDN: data = new IsdnRecord(buffer); break;
case RecordType.RT: data = new RTRecord(buffer); break;
case RecordType.NSAP: data = new NsapRecord(buffer, length); break;
case RecordType.SIG: data = new SigRecord(buffer, length); break;
case RecordType.KEY: data = new KeyRecord(buffer, length); break;
case RecordType.PX: data = new PXRecord(buffer); break;
case RecordType.AAAA: data = new AAAARecord(buffer); break;
case RecordType.LOC: data = new LocRecord(buffer); break;
case RecordType.SRV: data = new SrvRecord(buffer); break;
case RecordType.NAPTR: data = new NaptrRecord(buffer); break;
case RecordType.KX: data = new KXRecord(buffer); break;
case RecordType.A6: data = new A6Record(buffer); break;
case RecordType.DNAME: data = new DNameRecord(buffer); break;
case RecordType.DS: data = new DSRecord(buffer, length); break;
case RecordType.TKEY: data = new TKeyRecord(buffer); break;
case RecordType.TSIG: data = new TSigRecord(buffer); break;
default: throw new DnsQueryException("Invalid DNS Record Type in DNS Response", null);
}
}
catch (Exception ex)
{
data = new ExceptionRecord(ex.Message);
throw ex;
}
}
/// <summary>
/// Implementation Reference RFC 2535
/// </summary>
/// <param name="buffer"></param>
/// <param name="length"></param>
public SigRecord(DataBuffer buffer, int length)
{
int pos = buffer.Position;
coveredType = buffer.ReadShortInt();
algorithm = buffer.ReadByte();
numLabels = buffer.ReadByte();
expiration = buffer.ReadUInt();
inception = buffer.ReadUInt();
keyTag = buffer.ReadShortInt();
signer = buffer.ReadDomainName();
buffer.Position = pos - length;
}
/// <summary>
/// Implementation Reference RFC 3363
/// </summary>
/// <param name="buffer"></param>
public A6Record(DataBuffer buffer)
{
prefixLength = buffer.ReadByte();
if(prefixLength == 0) //Only Address Present
{
ipAddress = buffer.ReadIPv6Address();
}
else if (prefixLength == 128) //Only Domain Name Present
{
domain = buffer.ReadDomainName();
}
else //Address and Domain Name Present
{
ipAddress = buffer.ReadIPv6Address();
domain = buffer.ReadDomainName();
}
}
/// <summary>
/// Given a byte array interpret them as a DnsEntry
/// </summary>
/// <param name="response"></param>
public DnsAnswer(byte[] response)
{
questions = new List<Question>();
answers = new List<Answer>();
servers = new List<Server>();
additional = new List<Record>();
exceptions = new List<Exception>();
DataBuffer buffer = new DataBuffer(response, 2);
byte bits1 = buffer.ReadByte();
byte bits2 = buffer.ReadByte();
//Mask off return code
int returnCode = bits2 & 15;
if (returnCode > 6) returnCode = 6;
this.returnCode = (ReturnCode)returnCode;
//Get Additional Flags
authoritative = TestBit(bits1, 2);
recursive = TestBit(bits2, 8);
truncated = TestBit(bits1, 1);
int nQuestions = buffer.ReadBEShortInt();
int nAnswers = buffer.ReadBEShortInt();
int nServers = buffer.ReadBEShortInt();
int nAdditional = buffer.ReadBEShortInt();
//read in questions
for(int i = 0; i < nQuestions; i++)
{
try
{
questions.Add(new Question(buffer));
}
catch (Exception ex)
{
exceptions.Add(ex);
}
}
//read in answers
for(int i = 0; i < nAnswers; i++)
{
try
{
answers.Add(new Answer(buffer));
}
catch (Exception ex)
{
exceptions.Add(ex);
}
}
//read in servers
for(int i = 0; i < nServers; i++)
{
try
{
servers.Add(new Server(buffer));
}
catch (Exception ex)
{
exceptions.Add(ex);
}
}
//read in additional records
for(int i = 0; i < nAdditional; i++)
{
try
{
additional.Add(new Record(buffer));
}
catch (Exception ex)
{
exceptions.Add(ex);
}
}
}
/// <summary>
/// Given a byte array interpret them as a DnsEntry
/// </summary>
/// <param name="response"></param>
public DnsAnswer(byte[] response)
{
questions = new List <Question>();
answers = new List <Answer>();
servers = new List <Server>();
additional = new List <Record>();
exceptions = new List <Exception>();
DataBuffer buffer = new DataBuffer(response, 2);
byte bits1 = buffer.ReadByte();
byte bits2 = buffer.ReadByte();
//Mask off return code
int returnCode = bits2 & 15;
if (returnCode > 6)
{
returnCode = 6;
}
this.returnCode = (ReturnCode)returnCode;
//Get Additional Flags
authoritative = TestBit(bits1, 2);
recursive = TestBit(bits2, 8);
truncated = TestBit(bits1, 1);
int nQuestions = buffer.ReadBEShortInt();
int nAnswers = buffer.ReadBEShortInt();
int nServers = buffer.ReadBEShortInt();
int nAdditional = buffer.ReadBEShortInt();
//read in questions
for (int i = 0; i < nQuestions; i++)
{
try
{
questions.Add(new Question(buffer));
}
catch (Exception ex)
{
exceptions.Add(ex);
}
}
//read in answers
for (int i = 0; i < nAnswers; i++)
{
try
{
answers.Add(new Answer(buffer));
}
catch (Exception ex)
{
exceptions.Add(ex);
}
}
//read in servers
for (int i = 0; i < nServers; i++)
{
try
{
servers.Add(new Server(buffer));
}
catch (Exception ex)
{
exceptions.Add(ex);
}
}
//read in additional records
for (int i = 0; i < nAdditional; i++)
{
try
{
additional.Add(new Record(buffer));
}
catch (Exception ex)
{
exceptions.Add(ex);
}
}
}
