public override void SetRecords(DnsResourceRecordType type, IReadOnlyList <DnsResourceRecord> records)
{
switch (type)
{
case DnsResourceRecordType.SOA:
if ((records.Count != 1) || !records[0].Name.Equals(_name, StringComparison.OrdinalIgnoreCase))
{
throw new InvalidOperationException("Invalid SOA record.");
}
DnsResourceRecord existingSoaRecord = _entries[DnsResourceRecordType.SOA][0];
DnsResourceRecord newSoaRecord = records[0];
existingSoaRecord.CopyRecordInfoFrom(newSoaRecord);
break;
default:
throw new InvalidOperationException("Cannot set records in stub zone.");
}
}
private async Task <bool> RefreshZoneAsync(IReadOnlyList <NameServerAddress> nameServers)
{
try
{
{
LogManager log = _dnsServer.LogManager;
if (log != null)
{
log.Write("DNS Server has started zone refresh for stub zone: " + (_name == "" ? "<root>" : _name));
}
}
DnsClient client = new DnsClient(nameServers);
client.Proxy = _dnsServer.Proxy;
client.PreferIPv6 = _dnsServer.PreferIPv6;
client.Timeout = REFRESH_TIMEOUT;
client.Retries = REFRESH_RETRIES;
client.Concurrency = 1;
DnsDatagram soaRequest = new DnsDatagram(0, false, DnsOpcode.StandardQuery, false, false, false, false, false, false, DnsResponseCode.NoError, new DnsQuestionRecord[] { new DnsQuestionRecord(_name, DnsResourceRecordType.SOA, DnsClass.IN) }, null, null, null, DnsDatagram.EDNS_DEFAULT_UDP_PAYLOAD_SIZE);
DnsDatagram soaResponse = await client.ResolveAsync(soaRequest);
if (soaResponse.RCODE != DnsResponseCode.NoError)
{
LogManager log = _dnsServer.LogManager;
if (log != null)
{
log.Write("DNS Server received RCODE=" + soaResponse.RCODE.ToString() + " for '" + (_name == "" ? "<root>" : _name) + "' stub zone refresh from: " + soaResponse.Metadata.NameServerAddress.ToString());
}
return(false);
}
if ((soaResponse.Answer.Count < 1) || (soaResponse.Answer[0].Type != DnsResourceRecordType.SOA) || !_name.Equals(soaResponse.Answer[0].Name, StringComparison.OrdinalIgnoreCase))
{
LogManager log = _dnsServer.LogManager;
if (log != null)
{
log.Write("DNS Server received an empty response for SOA query for '" + (_name == "" ? "<root>" : _name) + "' stub zone refresh from: " + soaResponse.Metadata.NameServerAddress.ToString());
}
return(false);
}
DnsResourceRecord currentSoaRecord = _entries[DnsResourceRecordType.SOA][0];
DnsResourceRecord receivedSoaRecord = soaResponse.Answer[0];
DnsSOARecordData currentSoa = currentSoaRecord.RDATA as DnsSOARecordData;
DnsSOARecordData receivedSoa = receivedSoaRecord.RDATA as DnsSOARecordData;
//compare using sequence space arithmetic
if (!_resync && !currentSoa.IsZoneUpdateAvailable(receivedSoa))
{
LogManager log = _dnsServer.LogManager;
if (log != null)
{
log.Write("DNS Server successfully checked for '" + (_name == "" ? "<root>" : _name) + "' stub zone update from: " + soaResponse.Metadata.NameServerAddress.ToString());
}
return(true);
}
//update available; do zone sync with TCP transport
List <NameServerAddress> tcpNameServers = new List <NameServerAddress>();
foreach (NameServerAddress nameServer in nameServers)
{
tcpNameServers.Add(nameServer.ChangeProtocol(DnsTransportProtocol.Tcp));
}
nameServers = tcpNameServers;
client = new DnsClient(nameServers);
client.Proxy = _dnsServer.Proxy;
client.PreferIPv6 = _dnsServer.PreferIPv6;
client.Timeout = REFRESH_TIMEOUT;
client.Retries = REFRESH_RETRIES;
client.Concurrency = 1;
DnsDatagram nsRequest = new DnsDatagram(0, false, DnsOpcode.StandardQuery, false, false, false, false, false, false, DnsResponseCode.NoError, new DnsQuestionRecord[] { new DnsQuestionRecord(_name, DnsResourceRecordType.NS, DnsClass.IN) });
DnsDatagram nsResponse = await client.ResolveAsync(nsRequest);
if (nsResponse.RCODE != DnsResponseCode.NoError)
{
LogManager log = _dnsServer.LogManager;
if (log != null)
{
log.Write("DNS Server received RCODE=" + nsResponse.RCODE.ToString() + " for '" + (_name == "" ? "<root>" : _name) + "' stub zone refresh from: " + nsResponse.Metadata.NameServerAddress.ToString());
}
return(false);
}
if (nsResponse.Answer.Count < 1)
{
LogManager log = _dnsServer.LogManager;
if (log != null)
{
log.Write("DNS Server received an empty response for NS query for '" + (_name == "" ? "<root>" : _name) + "' stub zone from: " + nsResponse.Metadata.NameServerAddress.ToString());
}
return(false);
}
//prepare sync records
List <DnsResourceRecord> nsRecords = new List <DnsResourceRecord>(nsResponse.Answer.Count);
foreach (DnsResourceRecord record in nsResponse.Answer)
{
if ((record.Type == DnsResourceRecordType.NS) && record.Name.Equals(_name, StringComparison.OrdinalIgnoreCase))
{
record.SyncGlueRecords(nsResponse.Additional);
nsRecords.Add(record);
}
}
receivedSoaRecord.CopyRecordInfoFrom(currentSoaRecord);
//sync records
_entries[DnsResourceRecordType.NS] = nsRecords;
_entries[DnsResourceRecordType.SOA] = new DnsResourceRecord[] { receivedSoaRecord };
{
LogManager log = _dnsServer.LogManager;
if (log != null)
{
log.Write("DNS Server successfully refreshed '" + (_name == "" ? "<root>" : _name) + "' stub zone from: " + nsResponse.Metadata.NameServerAddress.ToString());
}
}
return(true);
}
catch (Exception ex)
{
LogManager log = _dnsServer.LogManager;
if (log != null)
{
string strNameServers = null;
foreach (NameServerAddress nameServer in nameServers)
{
if (strNameServers == null)
{
strNameServers = nameServer.ToString();
}
else
{
strNameServers += ", " + nameServer.ToString();
}
}
log.Write("DNS Server failed to refresh '" + (_name == "" ? "<root>" : _name) + "' stub zone from: " + strNameServers);
log.Write(ex);
}
return(false);
}
}
