diff --git a/DnsServerCore/Dns/DnsServer.cs b/DnsServerCore/Dns/DnsServer.cs
index 534a74bf..67c977e1 100644
--- a/DnsServerCore/Dns/DnsServer.cs
+++ b/DnsServerCore/Dns/DnsServer.cs
@@ -82,6 +82,8 @@ namespace DnsServerCore.Dns
readonly BlockListZoneManager _blockListZoneManager;
readonly CacheZoneManager _cacheZoneManager = new CacheZoneManager();
+ readonly ResolverDnsCache _dnsCache;
+
readonly DnsARecord _aRecord = new DnsARecord(IPAddress.Any);
readonly DnsAAAARecord _aaaaRecord = new DnsAAAARecord(IPAddress.IPv6Any);
readonly DnsTXTRecord _txtRecord = new DnsTXTRecord("blockList=custom");
@@ -163,6 +165,8 @@ namespace DnsServerCore.Dns
_blockedZoneManager = new BlockedZoneManager(this);
_blockListZoneManager = new BlockListZoneManager(this);
+ _dnsCache = new ResolverDnsCache(_authZoneManager, _cacheZoneManager);
+
//init stats
string statsFolder = Path.Combine(_configFolder, "stats");
@@ -847,7 +851,7 @@ namespace DnsServerCore.Dns
{
try
{
- string statusString = statusCode + " " + GetStatusString((HttpStatusCode)statusCode);
+ string statusString = statusCode + " " + GetHttpStatusString((HttpStatusCode)statusCode);
byte[] bufferContent = Encoding.UTF8.GetBytes("" + statusString + "" + statusString + "
" + (message == null ? "" : "" + message + "
") + "");
byte[] bufferHeader = Encoding.UTF8.GetBytes("HTTP/1.1 " + statusString + "\r\nDate: " + DateTime.UtcNow.ToString("r") + "\r\nContent-Type: text/html; charset=utf-8\r\nContent-Length: " + bufferContent.Length + "\r\nX-Robots-Tag: noindex, nofollow\r\n\r\n");
@@ -859,7 +863,7 @@ namespace DnsServerCore.Dns
{ }
}
- internal static string GetStatusString(HttpStatusCode statusCode)
+ internal static string GetHttpStatusString(HttpStatusCode statusCode)
{
StringBuilder sb = new StringBuilder();
@@ -924,15 +928,10 @@ namespace DnsServerCore.Dns
return new DnsDatagram(request.Identifier, true, DnsOpcode.StandardQuery, false, false, request.RecursionDesired, isRecursionAllowed, false, false, DnsResponseCode.NotImplemented, request.Question);
default:
- //query authoritative zone
- DnsDatagram response = ProcessAuthoritativeQuery(request, isRecursionAllowed);
-
- if ((response.RCODE != DnsResponseCode.Refused) || !request.RecursionDesired || !isRecursionAllowed)
- return response;
+ DnsDatagram response;
//check in allowed zone
bool inAllowedZone = _allowedZoneManager.Query(request).RCODE != DnsResponseCode.Refused;
-
if (!inAllowedZone)
{
//check in blocked zone and block list zone
@@ -941,8 +940,14 @@ namespace DnsServerCore.Dns
return response;
}
+ //query authoritative zone
+ response = ProcessAuthoritativeQuery(request, isRecursionAllowed);
+
+ if ((response.RCODE != DnsResponseCode.Refused) || !request.RecursionDesired || !isRecursionAllowed)
+ return response;
+
//do recursive query
- return ProcessRecursiveQuery(request, !inAllowedZone, null, null, false);
+ return ProcessRecursiveQuery(request, null, null, !inAllowedZone, false);
}
}
catch (Exception ex)
@@ -1190,81 +1195,7 @@ namespace DnsServerCore.Dns
switch (lastRR.Type)
{
case DnsResourceRecordType.CNAME:
- List responseAnswer = new List();
- responseAnswer.AddRange(response.Answer);
-
- DnsDatagram lastResponse;
-
- int queryCount = 0;
- do
- {
- DnsDatagram newRequest = new DnsDatagram(0, false, DnsOpcode.StandardQuery, false, false, request.RecursionDesired, false, false, false, DnsResponseCode.NoError, new DnsQuestionRecord[] { new DnsQuestionRecord((lastRR.RDATA as DnsCNAMERecord).Domain, questionType, request.Question[0].Class) });
-
- //query authoritative zone first
- lastResponse = _authZoneManager.Query(newRequest);
-
- if (lastResponse.RCODE == DnsResponseCode.Refused)
- {
- //not found in auth zone
- if (newRequest.RecursionDesired && isRecursionAllowed)
- {
- //do recursion
- lastResponse = ProcessRecursiveQuery(newRequest, false, null, null, false);
- }
- else
- {
- lastResponse = response; //response is logically last valid response
- break; //break since no recursion allowed/desired
- }
- }
- else if ((lastResponse.Answer.Count > 0) && (lastResponse.Answer[0].Type == DnsResourceRecordType.ANAME))
- {
- lastResponse = ProcessANAME(request, lastResponse, isRecursionAllowed);
- }
- else if ((lastResponse.Answer.Count == 0) && (lastResponse.Authority.Count > 0))
- {
- //found delegated/forwarded zone
- lastResponse = ProcessAuthoritySection(newRequest, lastResponse, isRecursionAllowed);
- }
-
- //check last response
- if (lastResponse.Answer.Count == 0)
- break; //cannot proceed to resolve cname further
-
- responseAnswer.AddRange(lastResponse.Answer);
-
- lastRR = lastResponse.Answer[lastResponse.Answer.Count - 1];
-
- if (lastRR.Type != DnsResourceRecordType.CNAME)
- break; //cname was resolved
- }
- while (++queryCount < MAX_CNAME_HOPS);
-
- DnsResponseCode rcode;
- IReadOnlyList authority = null;
- IReadOnlyList additional = null;
-
- if ((lastResponse.RCODE == DnsResponseCode.Refused) && !(request.RecursionDesired && isRecursionAllowed))
- {
- rcode = DnsResponseCode.NoError;
- }
- else
- {
- rcode = lastResponse.RCODE;
-
- if (lastResponse.AuthoritativeAnswer)
- {
- authority = lastResponse.Authority;
- additional = lastResponse.Additional;
- }
- else
- {
- if ((lastResponse.Authority.Count > 0) && (lastResponse.Authority[0].Type == DnsResourceRecordType.SOA))
- authority = lastResponse.Authority;
- }
- }
-
- return new DnsDatagram(request.Identifier, true, DnsOpcode.StandardQuery, lastResponse.AuthoritativeAnswer, false, request.RecursionDesired, isRecursionAllowed, false, false, rcode, request.Question, responseAnswer, authority, additional) { Tag = response.Tag };
+ return ProcessCNAME(request, response, isRecursionAllowed, false);
case DnsResourceRecordType.ANAME:
return ProcessANAME(request, response, isRecursionAllowed);
@@ -1273,13 +1204,166 @@ namespace DnsServerCore.Dns
}
else if (response.Authority.Count > 0)
{
- return ProcessAuthoritySection(request, response, isRecursionAllowed);
+ switch (response.Authority[0].Type)
+ {
+ case DnsResourceRecordType.NS:
+ if (request.RecursionDesired && isRecursionAllowed)
+ {
+ //do recursive resolution using response authority name servers
+ List nameServers = NameServerAddress.GetNameServersFromResponse(response, _preferIPv6, false);
+
+ return ProcessRecursiveQuery(request, nameServers, null, false, false);
+ }
+
+ break;
+
+ case DnsResourceRecordType.FWD:
+ if ((response.Authority.Count == 1) && (response.Authority[0].RDATA as DnsForwarderRecord).Forwarder.Equals("this-server", StringComparison.OrdinalIgnoreCase))
+ {
+ //do conditional forwarding via "this-server"
+ return ProcessRecursiveQuery(request, null, null, false, false);
+ }
+ else
+ {
+ //do conditional forwarding
+ List forwarders = new List(response.Authority.Count);
+
+ foreach (DnsResourceRecord rr in response.Authority)
+ {
+ if (rr.Type == DnsResourceRecordType.FWD)
+ forwarders.Add((rr.RDATA as DnsForwarderRecord).NameServer);
+ }
+
+ return ProcessRecursiveQuery(request, null, forwarders, false, false);
+ }
+ }
}
}
return response;
}
+ private DnsDatagram ProcessCNAME(DnsDatagram request, DnsDatagram response, bool isRecursionAllowed, bool cacheRefreshOperation)
+ {
+ List responseAnswer = new List();
+ responseAnswer.AddRange(response.Answer);
+
+ DnsDatagram lastResponse;
+ bool isAuthoritativeAnswer = response.AuthoritativeAnswer;
+ string lastDomain = (response.Answer[response.Answer.Count - 1].RDATA as DnsCNAMERecord).Domain;
+
+ int queryCount = 0;
+ do
+ {
+ DnsDatagram newRequest = new DnsDatagram(0, false, DnsOpcode.StandardQuery, false, false, request.RecursionDesired, false, false, false, DnsResponseCode.NoError, new DnsQuestionRecord[] { new DnsQuestionRecord(lastDomain, request.Question[0].Type, request.Question[0].Class) });
+
+ //query authoritative zone first
+ lastResponse = _authZoneManager.Query(newRequest);
+
+ if (lastResponse.RCODE == DnsResponseCode.Refused)
+ {
+ //not found in auth zone
+ if (newRequest.RecursionDesired && isRecursionAllowed)
+ {
+ //do recursion
+ lastResponse = RecursiveResolve(newRequest, null, null, false, cacheRefreshOperation);
+ isAuthoritativeAnswer = false;
+ }
+ else
+ {
+ //break since no recursion allowed/desired
+ break;
+ }
+ }
+ else if ((lastResponse.Answer.Count > 0) && (lastResponse.Answer[0].Type == DnsResourceRecordType.ANAME))
+ {
+ lastResponse = ProcessANAME(request, lastResponse, isRecursionAllowed);
+ }
+ else if ((lastResponse.Answer.Count == 0) && (lastResponse.Authority.Count > 0))
+ {
+ //found delegated/forwarded zone
+ switch (lastResponse.Authority[0].Type)
+ {
+ case DnsResourceRecordType.NS:
+ if (newRequest.RecursionDesired && isRecursionAllowed)
+ {
+ //do recursive resolution using last response authority name servers
+ List nameServers = NameServerAddress.GetNameServersFromResponse(lastResponse, _preferIPv6, false);
+
+ lastResponse = RecursiveResolve(newRequest, nameServers, null, false, false);
+ isAuthoritativeAnswer = false;
+ }
+
+ break;
+
+ case DnsResourceRecordType.FWD:
+ if ((lastResponse.Authority.Count == 1) && (lastResponse.Authority[0].RDATA as DnsForwarderRecord).Forwarder.Equals("this-server", StringComparison.OrdinalIgnoreCase))
+ {
+ //do conditional forwarding via "this-server"
+ lastResponse = RecursiveResolve(newRequest, null, null, false, false);
+ isAuthoritativeAnswer = false;
+ }
+ else
+ {
+ //do conditional forwarding
+ List forwarders = new List(lastResponse.Authority.Count);
+
+ foreach (DnsResourceRecord rr in lastResponse.Authority)
+ {
+ if (rr.Type == DnsResourceRecordType.FWD)
+ forwarders.Add((rr.RDATA as DnsForwarderRecord).NameServer);
+ }
+
+ lastResponse = RecursiveResolve(newRequest, null, forwarders, false, false);
+ isAuthoritativeAnswer = false;
+ }
+
+ break;
+ }
+ }
+
+ //check last response
+ if (lastResponse.Answer.Count == 0)
+ break; //cannot proceed to resolve further
+
+ responseAnswer.AddRange(lastResponse.Answer);
+
+ DnsResourceRecord lastRR = lastResponse.Answer[lastResponse.Answer.Count - 1];
+
+ if (lastRR.Type != DnsResourceRecordType.CNAME)
+ break; //cname was resolved
+
+ lastDomain = (lastRR.RDATA as DnsCNAMERecord).Domain;
+ }
+ while (++queryCount < MAX_CNAME_HOPS);
+
+ DnsResponseCode rcode;
+ IReadOnlyList authority = null;
+ IReadOnlyList additional = null;
+
+ if ((lastResponse.RCODE == DnsResponseCode.Refused) && !(request.RecursionDesired && isRecursionAllowed))
+ {
+ rcode = DnsResponseCode.NoError;
+ }
+ else
+ {
+ rcode = lastResponse.RCODE;
+
+ if (isAuthoritativeAnswer)
+ {
+ authority = response.Authority;
+ additional = response.Additional;
+ }
+ else
+ {
+ if ((lastResponse.Authority.Count > 0) && (lastResponse.Authority[0].Type == DnsResourceRecordType.SOA))
+ authority = lastResponse.Authority;
+ }
+ }
+
+ return new DnsDatagram(request.Identifier, true, DnsOpcode.StandardQuery, isAuthoritativeAnswer, false, request.RecursionDesired, isRecursionAllowed, false, false, rcode, request.Question, responseAnswer, authority, additional) { Tag = response.Tag };
+ }
+
private DnsDatagram ProcessANAME(DnsDatagram request, DnsDatagram response, bool isRecursionAllowed)
{
List responseAnswer = new List();
@@ -1302,12 +1386,42 @@ namespace DnsServerCore.Dns
if (lastResponse.RCODE == DnsResponseCode.Refused)
{
//not found in auth zone; do recursion
- lastResponse = ProcessRecursiveQuery(newRequest, false, null, null, false);
+ lastResponse = RecursiveResolve(newRequest, null, null, false, false);
}
else if ((lastResponse.Answer.Count == 0) && (lastResponse.Authority.Count > 0))
{
//found delegated/forwarded zone
- lastResponse = ProcessAuthoritySection(newRequest, lastResponse, true);
+ switch (lastResponse.Authority[0].Type)
+ {
+ case DnsResourceRecordType.NS:
+ //do recursive resolution using last response authority name servers
+ List nameServers = NameServerAddress.GetNameServersFromResponse(lastResponse, _preferIPv6, false);
+
+ lastResponse = RecursiveResolve(newRequest, nameServers, null, false, false);
+ break;
+
+ case DnsResourceRecordType.FWD:
+ if ((lastResponse.Authority.Count == 1) && (lastResponse.Authority[0].RDATA as DnsForwarderRecord).Forwarder.Equals("this-server", StringComparison.OrdinalIgnoreCase))
+ {
+ //do conditional forwarding via "this-server"
+ lastResponse = RecursiveResolve(newRequest, null, null, false, false);
+ }
+ else
+ {
+ //do conditional forwarding
+ List forwarders = new List(lastResponse.Authority.Count);
+
+ foreach (DnsResourceRecord rr in lastResponse.Authority)
+ {
+ if (rr.Type == DnsResourceRecordType.FWD)
+ forwarders.Add((rr.RDATA as DnsForwarderRecord).NameServer);
+ }
+
+ lastResponse = RecursiveResolve(newRequest, null, forwarders, false, false);
+ }
+
+ break;
+ }
}
//check last response
@@ -1346,45 +1460,6 @@ namespace DnsServerCore.Dns
return new DnsDatagram(request.Identifier, true, DnsOpcode.StandardQuery, true, false, request.RecursionDesired, isRecursionAllowed, false, false, rcode, request.Question, responseAnswer, response.Authority, response.Additional) { Tag = response.Tag };
}
- private DnsDatagram ProcessAuthoritySection(DnsDatagram request, DnsDatagram response, bool isRecursionAllowed)
- {
- switch (response.Authority[0].Type)
- {
- case DnsResourceRecordType.NS:
- if (request.RecursionDesired && isRecursionAllowed)
- {
- //do recursive resolution using response authority name servers
- List nameServers = NameServerAddress.GetNameServersFromResponse(response, _preferIPv6, false);
-
- return ProcessRecursiveQuery(request, false, nameServers, null, false);
- }
-
- break;
-
- case DnsResourceRecordType.FWD:
- if ((response.Authority.Count == 1) && (response.Authority[0].RDATA as DnsForwarderRecord).Forwarder.Equals("this-server", StringComparison.OrdinalIgnoreCase))
- {
- //do conditional forwarding via "this-server"
- return ProcessRecursiveQuery(request, false, null, null, false);
- }
- else
- {
- //do conditional forwarding
- List forwarders = new List(response.Authority.Count);
-
- foreach (DnsResourceRecord rr in response.Authority)
- {
- if (rr.Type == DnsResourceRecordType.FWD)
- forwarders.Add((rr.RDATA as DnsForwarderRecord).NameServer);
- }
-
- return ProcessRecursiveQuery(request, false, null, forwarders, false);
- }
- }
-
- return response;
- }
-
private DnsDatagram ProcessBlockedQuery(DnsDatagram request)
{
DnsDatagram response = _blockedZoneManager.Query(request);
@@ -1431,113 +1506,61 @@ namespace DnsServerCore.Dns
return response;
}
- private DnsDatagram ProcessRecursiveQuery(DnsDatagram request, bool checkForCnameCloaking, IReadOnlyList viaNameServers, IReadOnlyList viaForwarders, bool cacheRefreshOperation)
+ private DnsDatagram ProcessRecursiveQuery(DnsDatagram request, IReadOnlyList viaNameServers, IReadOnlyList viaForwarders, bool checkForCnameCloaking, bool cacheRefreshOperation)
{
DnsDatagram response = RecursiveResolve(request, viaNameServers, viaForwarders, false, cacheRefreshOperation);
- DnsResponseCode rcode = response.RCODE;
- IReadOnlyList answer = response.Answer;
- IReadOnlyList authority = null;
- IReadOnlyList additional = null;
-
if (response.Answer.Count > 0)
{
- bool cnameCheckPassed = true;
+ DnsResourceRecordType questionType = request.Question[0].Type;
+ DnsResourceRecord lastRR = response.Answer[response.Answer.Count - 1];
+
+ if ((lastRR.Type != questionType) && (lastRR.Type == DnsResourceRecordType.CNAME) && (questionType != DnsResourceRecordType.ANY))
+ response = ProcessCNAME(request, response, true, cacheRefreshOperation);
if (checkForCnameCloaking && (response.Answer.Count > 1))
{
- List responseAnswer = new List();
-
- foreach (DnsResourceRecord record in response.Answer)
+ for (int i = 0; i < response.Answer.Count; i++)
{
- responseAnswer.Add(record);
+ DnsResourceRecord record = response.Answer[i];
- if (record.Type == DnsResourceRecordType.CNAME)
+ if (record.Type != DnsResourceRecordType.CNAME)
+ break; //no further CNAME records exists
+
+ DnsDatagram newRequest = new DnsDatagram(0, false, DnsOpcode.StandardQuery, false, false, true, false, false, false, DnsResponseCode.NoError, new DnsQuestionRecord[] { new DnsQuestionRecord((record.RDATA as DnsCNAMERecord).Domain, request.Question[0].Type, request.Question[0].Class) });
+ DnsDatagram lastResponse = ProcessBlockedQuery(newRequest);
+ if (lastResponse != null)
{
- DnsDatagram newRequest = new DnsDatagram(0, false, DnsOpcode.StandardQuery, false, false, true, false, false, false, DnsResponseCode.NoError, new DnsQuestionRecord[] { new DnsQuestionRecord((record.RDATA as DnsCNAMERecord).Domain, request.Question[0].Type, request.Question[0].Class) });
- DnsDatagram lastResponse = ProcessBlockedQuery(newRequest);
- if (lastResponse != null)
- {
- //found cname cloaking
- cnameCheckPassed = false;
- responseAnswer.AddRange(lastResponse.Answer);
+ //found cname cloaking
+ List answer = new List();
- rcode = lastResponse.RCODE;
- answer = responseAnswer;
+ //copy previous CNAME records
+ for (int j = 0; j < i; j++)
+ answer.Add(record);
- if ((lastResponse.Authority.Count > 0) && (lastResponse.Authority[0].Type == DnsResourceRecordType.SOA))
- authority = lastResponse.Authority;
+ //copy last response answers
+ answer.AddRange(lastResponse.Answer);
- response.Tag = lastResponse.Tag;
- break;
- }
+ IReadOnlyList authority = null;
+
+ if ((lastResponse.Authority.Count > 0) && (lastResponse.Authority[0].Type == DnsResourceRecordType.SOA))
+ authority = lastResponse.Authority;
+
+ return new DnsDatagram(request.Identifier, true, DnsOpcode.StandardQuery, false, false, true, true, false, false, DnsResponseCode.NoError, request.Question, answer, authority) { Tag = lastResponse.Tag };
}
}
}
-
- if (cnameCheckPassed)
- {
- DnsResourceRecordType questionType = request.Question[0].Type;
- DnsResourceRecord lastRR = response.Answer[response.Answer.Count - 1];
-
- if ((lastRR.Type != questionType) && (lastRR.Type == DnsResourceRecordType.CNAME) && (questionType != DnsResourceRecordType.ANY))
- {
- List responseAnswer = new List();
- responseAnswer.AddRange(response.Answer);
-
- DnsDatagram lastResponse;
- int queryCount = 0;
-
- do
- {
- DnsDatagram newRequest = new DnsDatagram(0, false, DnsOpcode.StandardQuery, false, false, true, false, false, false, DnsResponseCode.NoError, new DnsQuestionRecord[] { new DnsQuestionRecord((lastRR.RDATA as DnsCNAMERecord).Domain, request.Question[0].Type, request.Question[0].Class) });
-
- if (checkForCnameCloaking)
- {
- //check if cname domain is blocked to prevent cname cloaking
- lastResponse = ProcessBlockedQuery(newRequest);
- if (lastResponse == null)
- lastResponse = RecursiveResolve(newRequest, null, null, false, cacheRefreshOperation); //cname is not blocked; so do recursive query
- }
- else
- {
- //do recursive query for cname
- lastResponse = RecursiveResolve(newRequest, null, null, false, cacheRefreshOperation);
- }
-
- if (lastResponse.Answer.Count == 0)
- break;
-
- responseAnswer.AddRange(lastResponse.Answer);
-
- lastRR = lastResponse.Answer[lastResponse.Answer.Count - 1];
-
- if (lastRR.Type == questionType)
- break;
-
- if (lastRR.Type != DnsResourceRecordType.CNAME)
- throw new DnsServerException("Invalid response received from DNS server.");
- }
- while (++queryCount < MAX_CNAME_HOPS);
-
- rcode = lastResponse.RCODE;
- answer = responseAnswer;
-
- if ((lastResponse.Authority.Count > 0) && (lastResponse.Authority[0].Type == DnsResourceRecordType.SOA))
- authority = lastResponse.Authority;
-
- response.Tag = lastResponse.Tag;
- }
- }
}
- if ((authority == null) && (response.Authority.Count > 0) && (response.Authority[0].Type == DnsResourceRecordType.SOA))
- authority = response.Authority;
+ //return response
+ {
+ IReadOnlyList authority = null;
- if ((response.Additional.Count > 0) && (request.Question[0].Type == DnsResourceRecordType.MX))
- additional = response.Additional;
+ if ((authority == null) && (response.Authority.Count > 0) && (response.Authority[0].Type == DnsResourceRecordType.SOA))
+ authority = response.Authority;
- return new DnsDatagram(request.Identifier, true, DnsOpcode.StandardQuery, false, false, true, true, false, false, rcode, request.Question, answer, authority, additional) { Tag = response.Tag };
+ return new DnsDatagram(request.Identifier, true, DnsOpcode.StandardQuery, false, false, true, true, false, false, response.RCODE, request.Question, response.Answer, authority) { Tag = response.Tag };
+ }
}
private DnsDatagram RecursiveResolve(DnsDatagram request, IReadOnlyList viaNameServers, IReadOnlyList viaForwarders, bool cachePrefetchOperation, bool cacheRefreshOperation)
@@ -1595,8 +1618,7 @@ namespace DnsServerCore.Dns
return null; //return null as prefetch worker thread does not need valid response and thus does not need to wait
//wait till short timeout for response
- bool signalled = queryHandle.WaitForResponse(1800, out DnsDatagram response); //1.8 sec wait as per draft-ietf-dnsop-serve-stale-04
- if (signalled)
+ if (queryHandle.WaitForResponse(1800, out DnsDatagram response)) //1.8 sec wait as per draft-ietf-dnsop-serve-stale-04
{
//resolver signaled
if (response != null)
@@ -1620,11 +1642,11 @@ namespace DnsServerCore.Dns
if (response != null)
return response;
- //no response available from resolver
+ //no response available from resolver or resolver had exception and no stale record was found
}
}
- //no response available respond with ServerFailure
+ //no response available; respond with ServerFailure
return new DnsDatagram(request.Identifier, true, DnsOpcode.StandardQuery, false, false, request.RecursionDesired, true, false, false, DnsResponseCode.ServerFailure, request.Question);
}
@@ -1655,7 +1677,7 @@ namespace DnsServerCore.Dns
foreach (NameServerAddress nameServerAddress in forwarders)
{
if (nameServerAddress.IsIPEndPointStale) //refresh forwarder IPEndPoint if stale
- nameServerAddress.RecursiveResolveIPAddress(_cacheZoneManager, null, _preferIPv6, _retries, _timeout);
+ nameServerAddress.RecursiveResolveIPAddress(_dnsCache, null, _preferIPv6, _retries, _timeout);
}
}
@@ -1679,9 +1701,9 @@ namespace DnsServerCore.Dns
IDnsCache dnsCache;
if (cachePrefetchOperation || cacheRefreshOperation)
- dnsCache = new ResolverPrefetchDnsCache(_cacheZoneManager, request.Question[0]);
+ dnsCache = new ResolverPrefetchDnsCache(_authZoneManager, _cacheZoneManager, request.Question[0]);
else
- dnsCache = _cacheZoneManager;
+ dnsCache = _dnsCache;
DnsDatagram response = DnsClient.RecursiveResolve(request.Question[0], viaNameServers, dnsCache, _proxy, _preferIPv6, _retries, _timeout, _maxStackCount);
queryHandle.Set(response);
@@ -1720,21 +1742,10 @@ namespace DnsServerCore.Dns
//fetch stale record
DnsDatagram cacheResponse = QueryCache(request, true);
- if ((cacheResponse == null) || ((cacheResponse.Answer.Count == 0) && (cacheResponse.Authority.Count == 0)))
+ if (cacheResponse == null)
{
- //no stale record or empty record found; cache new empty record to avoid frequent retries by the resolver
- DnsResponseCode rcode;
-
- if (cacheResponse == null)
- rcode = DnsResponseCode.ServerFailure;
- else
- rcode = cacheResponse.RCODE;
-
- DnsDatagram failureResponse = new DnsDatagram(request.Identifier, true, DnsOpcode.StandardQuery, false, false, request.RecursionDesired, true, false, false, rcode, request.Question);
-
- _cacheZoneManager.CacheResponse(failureResponse);
-
- queryHandle.Set(failureResponse);
+ //no stale record was found; signal null response to release waiting threads
+ queryHandle.Set(null);
}
else
{
@@ -1844,9 +1855,16 @@ namespace DnsServerCore.Dns
AuthZoneInfo zoneInfo = _authZoneManager.GetAuthZoneInfo(query.Key.Name);
if (zoneInfo != null)
{
- //zone is hosted
- if (!zoneInfo.Disabled)
- continue; //no cache refresh for zone that is hosted and enabled
+ switch (zoneInfo.Type)
+ {
+ case AuthZoneType.Primary:
+ case AuthZoneType.Secondary:
+ //zone is hosted
+ if (!zoneInfo.Disabled)
+ continue; //no cache refresh for zone that is hosted and enabled
+
+ break;
+ }
}
if (query.Key.Type == DnsResourceRecordType.ANY)
@@ -1903,7 +1921,7 @@ namespace DnsServerCore.Dns
{
//refresh cache
DnsDatagram request = new DnsDatagram(0, false, DnsOpcode.StandardQuery, false, false, true, false, false, false, DnsResponseCode.NoError, new DnsQuestionRecord[] { sampleQuestion });
- DnsDatagram response = ProcessRecursiveQuery(request, false, null, null, true);
+ DnsDatagram response = ProcessRecursiveQuery(request, null, null, false, true);
bool removeFromSampleList = true;
@@ -2449,6 +2467,9 @@ namespace DnsServerCore.Dns
public CacheZoneManager CacheZoneManager
{ get { return _cacheZoneManager; } }
+ public IDnsCache DnsCache
+ { get { return _dnsCache; } }
+
public bool AllowRecursion
{
get { return _allowRecursion; }