public DNSRecord(Domain name, AddressClass address_class, UInt32 ttl, IDNSResource resource)
{
Name = name;
AddressClass = address_class;
TimeToLive = ttl;
Resource = resource;
}
public bool Equals(IDNSResource other)
{
if (!(other is AAAAResource))
{
return(false);
}
var other_resource = (AAAAResource)other;
return
(this.Address.Equals(other_resource.Address)
);
}
public bool Equals(IDNSResource other)
{
if (!(other is PTRResource))
{
return(false);
}
var other_resource = (PTRResource)other;
return
(this.Pointer == other_resource.Pointer
);
}
public bool Equals(IDNSResource other)
{
if (!(other is CNAMEResource))
{
return(false);
}
var other_resource = (CNAMEResource)other;
return
(this.Alias == other_resource.Alias
);
}
public bool Equals(IDNSResource other)
{
if (!(other is NSResource))
{
return(false);
}
var other_resource = (NSResource)other;
return
(this.Nameserver == other_resource.Nameserver
);
}
public bool Equals(IDNSResource other)
{
if (!(other is MXResource))
{
return(false);
}
var other_resource = (MXResource)other;
return
(this.Preference == other_resource.Preference &&
this.Mailserver == other_resource.Mailserver
);
}
/**
* Decodes the raw bytes of a DNS resource record into an
* object.
*/
public static DNSRecord Unserialize(DNSInputStream stream)
{
var name = stream.ReadDomain();
var record_type = (ResourceRecordType)stream.ReadUInt16();
var class_type = (AddressClass)stream.ReadUInt16();
var ttl = stream.ReadUInt32();
var record_size = stream.ReadUInt16();
IDNSResource resource = null;
switch (record_type.Normalize())
{
case ResourceRecordType.HOST_ADDRESS:
resource = AResource.Unserialize(stream, record_size);
break;
case ResourceRecordType.NAME_SERVER:
resource = NSResource.Unserialize(stream, record_size);
break;
case ResourceRecordType.START_OF_AUTHORITY:
resource = SOAResource.Unserialize(stream, record_size);
break;
case ResourceRecordType.CANONICAL_NAME:
resource = CNAMEResource.Unserialize(stream, record_size);
break;
case ResourceRecordType.MAIL_EXCHANGE:
resource = MXResource.Unserialize(stream, record_size);
break;
case ResourceRecordType.POINTER:
resource = PTRResource.Unserialize(stream, record_size);
break;
case ResourceRecordType.HOST_6ADDRESS:
resource = AAAAResource.Unserialize(stream, record_size);
break;
case ResourceRecordType.UNSUPPORTED:
// Advance the byte counter - even if we can't parse it,
// we have to properly ignore it
stream.ReadBytes(record_size);
resource = null;
break;
}
return(new DNSRecord(name, class_type.Normalize(), ttl, resource));
}
public bool Equals(IDNSResource other)
{
if (!(other is SOAResource))
{
return(false);
}
var other_resource = (SOAResource)other;
return
(this.PrimaryNameServer == other_resource.PrimaryNameServer &&
this.Hostmaster == other_resource.Hostmaster &&
this.Serial == other_resource.Serial &&
this.RefreshSeconds == other_resource.RefreshSeconds &&
this.RetrySeconds == other_resource.RetrySeconds &&
this.ExpireSeconds == other_resource.ExpireSeconds &&
this.MinimumTTL == other_resource.MinimumTTL
);
}
/**
* Produces a new zone from an input XML file.
*/
public static DNSZone Unserialize(XmlDocument config)
{
DNSRecord start_of_authority = null;
var records = new List <DNSRecord>();
var relays = new List <EndPoint>();
if (config.DocumentElement.Name != "zone")
{
throw new InvalidDataException("Root element must be called zone");
}
foreach (var entry in config.DocumentElement.ChildNodes.OfType <XmlNode>())
{
if (entry.NodeType != XmlNodeType.Element)
{
logger.Trace("Ignoring node of type {0}", entry.NodeType);
continue;
}
bool is_record =
entry.Name == "A" ||
entry.Name == "NS" ||
entry.Name == "CNAME" ||
entry.Name == "MX" ||
entry.Name == "SOA" ||
entry.Name == "PTR" ||
entry.Name == "AAAA";
if (is_record)
{
if (entry.Attributes["name"] == null ||
entry.Attributes["class"] == null ||
entry.Attributes["ttl"] == null)
{
throw new InvalidDataException("Resource records must have 'name', 'class' and 'ttl' attributes");
}
var record_name = new Domain(entry.Attributes["name"].Value);
AddressClass record_class;
switch (entry.Attributes["class"].Value)
{
case "IN":
record_class = AddressClass.INTERNET;
break;
default:
throw new InvalidDataException("Only address class 'IN' is supported");
}
UInt32 record_ttl = 0;
try
{
record_ttl = UInt32.Parse(entry.Attributes["ttl"].Value);
}
catch (Exception err)
{
if (err is OverflowException || err is FormatException)
{
throw new InvalidDataException(entry.Attributes["ttl"].Value + " is not a valid TTL");
}
else
{
throw;
}
}
IDNSResource resource = null;
switch (entry.Name)
{
case "A":
if (entry.Attributes["address"] == null)
{
throw new InvalidDataException("A record must have address");
}
IPv4Address address;
try
{
address = IPv4Address.Parse(entry.Attributes["address"].Value);
}
catch (FormatException)
{
throw new InvalidDataException(entry.Attributes["address"].Value + " is not a valid IPv4 address");
}
resource = new AResource(address);
logger.Trace("A record: address={0}", ((AResource)resource).Address);
break;
case "NS":
if (entry.Attributes["nameserver"] == null)
{
throw new InvalidDataException("NS record must have a nameserver");
}
resource = new NSResource(new Domain(entry.Attributes["nameserver"].Value));
logger.Trace("NS record: nameserver={0}", ((NSResource)resource).Nameserver);
break;
case "CNAME":
if (entry.Attributes["alias"] == null)
{
throw new InvalidDataException("CNAME record must have an alias");
}
resource = new CNAMEResource(new Domain(entry.Attributes["alias"].Value));
logger.Trace("CNAME record: alias={0}", ((CNAMEResource)resource).Alias);
break;
case "MX":
if (entry.Attributes["priority"] == null ||
entry.Attributes["mailserver"] == null)
{
throw new InvalidDataException("MX record must have priority and mailserver");
}
var mailserver = new Domain(entry.Attributes["mailserver"].Value);
UInt16 preference = 0;
try
{
preference = UInt16.Parse(entry.Attributes["priority"].Value);
}
catch (Exception err)
{
if (err is OverflowException || err is FormatException)
{
throw new InvalidDataException(entry.Attributes["priority"].Value + " is not a valid priority value");
}
else
{
throw;
}
}
resource = new MXResource(preference, mailserver);
logger.Trace("MX record: priority={0} mailserver={1}",
((MXResource)resource).Preference,
((MXResource)resource).Mailserver);
break;
case "PTR":
if (entry.Attributes["pointer"] == null)
{
throw new InvalidDataException("PTR record must have pointer");
}
if (!reverse_zone_v4.IsSubdomain(record_name) && !reverse_zone_v6.IsSubdomain(record_name))
{
throw new InvalidDataException("PTR record be in the in-addr.arpa or ip6.arpa zone");
}
resource = new PTRResource(new Domain(entry.Attributes["pointer"].Value));
logger.Trace("PTR record: pointer={0}", ((PTRResource)resource).Pointer);
break;
case "AAAA":
if (entry.Attributes["address"] == null)
{
throw new InvalidDataException("AAAA record must have address");
}
IPv6Address v6address;
try
{
v6address = IPv6Address.Parse(entry.Attributes["address"].Value);
}
catch (FormatException)
{
throw new InvalidDataException(entry.Attributes["address"].Value + " is not a valid IPv4 address");
}
resource = new AAAAResource(v6address);
logger.Trace("AAAA record: address={0}", ((AAAAResource)resource).Address);
break;
case "SOA":
if (entry.Attributes["primary-ns"] == null ||
entry.Attributes["hostmaster"] == null ||
entry.Attributes["serial"] == null ||
entry.Attributes["refresh"] == null ||
entry.Attributes["retry"] == null ||
entry.Attributes["expire"] == null ||
entry.Attributes["min-ttl"] == null)
{
throw new InvalidDataException("SOA record missing one of: primary-ns, hostmaster, serial, refresh, retry, expire and min-ttl");
}
var primary_ns = new Domain(entry.Attributes["primary-ns"].Value);
var hostmaster = new Domain(entry.Attributes["hostmaster"].Value);
UInt32 serial = 0;
try
{
serial = UInt32.Parse(entry.Attributes["serial"].Value);
}
catch (Exception err)
{
if (err is OverflowException || err is FormatException)
{
throw new InvalidDataException(entry.Attributes["serial"].Value + " is not a valid serial number");
}
else
{
throw;
}
}
UInt32 refresh = 0;
try
{
refresh = UInt32.Parse(entry.Attributes["refresh"].Value);
}
catch (Exception err)
{
if (err is OverflowException || err is FormatException)
{
throw new InvalidDataException(entry.Attributes["refresh"].Value + " is not a valid refresh value");
}
else
{
throw;
}
}
UInt32 retry = 0;
try
{
retry = UInt32.Parse(entry.Attributes["retry"].Value);
}
catch (Exception err)
{
if (err is OverflowException || err is FormatException)
{
throw new InvalidDataException(entry.Attributes["retry"].Value + " is not a valid retry value");
}
else
{
throw;
}
}
UInt32 expire = 0;
try
{
expire = UInt32.Parse(entry.Attributes["expire"].Value);
}
catch (Exception err)
{
if (err is OverflowException || err is FormatException)
{
throw new InvalidDataException(entry.Attributes["expire"].Value + " is not a valid expire value");
}
else
{
throw;
}
}
UInt32 minttl = 0;
try
{
minttl = UInt32.Parse(entry.Attributes["min-ttl"].Value);
}
catch (Exception err)
{
if (err is OverflowException || err is FormatException)
{
throw new InvalidDataException(entry.Attributes["min-ttl"].Value + " is not a valid expire value");
}
else
{
throw;
}
}
resource = new SOAResource(primary_ns, hostmaster, serial, refresh, retry, expire, minttl);
logger.Trace("SOA record: primary-ns={0} hostmaster={1} serial={2} refresh={3} retry={4} expire={5} min-ttl={6}",
((SOAResource)resource).PrimaryNameServer,
((SOAResource)resource).Hostmaster,
((SOAResource)resource).Serial,
((SOAResource)resource).RefreshSeconds,
((SOAResource)resource).RetrySeconds,
((SOAResource)resource).ExpireSeconds,
((SOAResource)resource).MinimumTTL);
break;
}
var record = new DNSRecord(record_name, record_class, record_ttl, resource);
if (record.Resource.Type == ResourceRecordType.START_OF_AUTHORITY)
{
if (start_of_authority == null)
{
logger.Trace("Found SOA: {0}", record);
start_of_authority = record;
}
else
{
throw new InvalidDataException("Cannot have more than one SOA record in zone");
}
}
else
{
logger.Trace("Found other record: {0}", record);
records.Add(record);
}
}
else if (entry.Name == "relay")
{
if (entry.Attributes["address"] == null ||
entry.Attributes["port"] == null)
{
throw new InvalidDataException("relay record must have address and port");
}
IPAddress address;
int port;
try
{
address = IPAddress.Parse(entry.Attributes["address"].Value);
}
catch (FormatException)
{
throw new InvalidDataException(entry.Attributes["address"].Value + " is not a valid IPv4 address");
}
try
{
port = int.Parse(entry.Attributes["port"].Value);
}
catch (FormatException)
{
throw new InvalidDataException(entry.Attributes["port"].Value + " is not a valid port");
}
try
{
relays.Add(new IPEndPoint(address, port));
}
catch (ArgumentOutOfRangeException)
{
throw new InvalidDataException(entry.Attributes["port"].Value + " is not a valid port");
}
logger.Trace("Found relay: {0}:{1}", address, port);
}
else
{
throw new InvalidDataException(entry.Name + " is not a valid zone entry");
}
}
if (start_of_authority == null)
{
throw new InvalidDataException("Zone does not have SOA record");
}
var zone = new DNSZone(start_of_authority, relays.ToArray());
foreach (var record in records)
{
if (record.TimeToLive < ((SOAResource)start_of_authority.Resource).MinimumTTL)
{
logger.Trace("Correcting TTL: Record {0} has smaller TTL than SOA MinTTL {1}",
record, start_of_authority);
record.TimeToLive = ((SOAResource)start_of_authority.Resource).MinimumTTL;
}
zone.Add(record);
}
return(zone);
}
