From 135c22ebe8b545de4209a8ea72a072ed85e0bf1d Mon Sep 17 00:00:00 2001
From: Shreyas Zare <shreyas@technitium.com>
Date: Sat, 14 Nov 2020 16:49:50 +0530
Subject: [PATCH] StubZone: updated stub zone to not allow adding records since
 this will create inconsistency issues when resursive resolvers query the stub
 zone. Removed stub sub domain zone too.

---
 .../Dns/ZoneManagers/AuthZoneManager.cs       |  2 -
 DnsServerCore/Dns/Zones/StubSubDomainZone.cs  | 32 -----------
 DnsServerCore/Dns/Zones/StubZone.cs           | 53 ++-----------------
 3 files changed, 5 insertions(+), 82 deletions(-)
 delete mode 100644 DnsServerCore/Dns/Zones/StubSubDomainZone.cs

diff --git a/DnsServerCore/Dns/ZoneManagers/AuthZoneManager.cs b/DnsServerCore/Dns/ZoneManagers/AuthZoneManager.cs
index e3046631..1fef40bf 100644
--- a/DnsServerCore/Dns/ZoneManagers/AuthZoneManager.cs
+++ b/DnsServerCore/Dns/ZoneManagers/AuthZoneManager.cs
@@ -232,8 +232,6 @@ namespace DnsServerCore.Dns.ZoneManagers
                     return new PrimarySubDomainZone(authZone as PrimaryZone, domain);
                 else if (authZone is SecondaryZone)
                     return new SecondarySubDomainZone(domain);
-                else if (authZone is StubZone)
-                    return new StubSubDomainZone(domain);
                 else if (authZone is ForwarderZone)
                     return new ForwarderSubDomainZone(domain);
 
diff --git a/DnsServerCore/Dns/Zones/StubSubDomainZone.cs b/DnsServerCore/Dns/Zones/StubSubDomainZone.cs
deleted file mode 100644
index 145fdef1..00000000
--- a/DnsServerCore/Dns/Zones/StubSubDomainZone.cs
+++ /dev/null
@@ -1,32 +0,0 @@
-/*
-Technitium DNS Server
-Copyright (C) 2020  Shreyas Zare (shreyas@technitium.com)
-
-This program is free software: you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation, either version 3 of the License, or
-(at your option) any later version.
-
-This program is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-GNU General Public License for more details.
-
-You should have received a copy of the GNU General Public License
-along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
-*/
-
-namespace DnsServerCore.Dns.Zones
-{
-    class StubSubDomainZone : SubDomainZone
-    {
-        #region constructor
-
-        public StubSubDomainZone(string name)
-            : base(name)
-        { }
-
-        #endregion
-    }
-}
diff --git a/DnsServerCore/Dns/Zones/StubZone.cs b/DnsServerCore/Dns/Zones/StubZone.cs
index d0282cbc..27f5e13a 100644
--- a/DnsServerCore/Dns/Zones/StubZone.cs
+++ b/DnsServerCore/Dns/Zones/StubZone.cs
@@ -332,12 +332,6 @@ namespace DnsServerCore.Dns.Zones
         {
             switch (type)
             {
-                case DnsResourceRecordType.CNAME:
-                    throw new InvalidOperationException("Cannot set CNAME record to zone root.");
-
-                case DnsResourceRecordType.NS:
-                    throw new InvalidOperationException("Cannot set NS records at stub zone root.");
-
                 case DnsResourceRecordType.SOA:
                     if ((records.Count != 1) || !records[0].Name.Equals(_name, StringComparison.OrdinalIgnoreCase))
                         throw new InvalidOperationException("Invalid SOA record.");
@@ -346,65 +340,28 @@ namespace DnsServerCore.Dns.Zones
                     break;
 
                 default:
-                    base.SetRecords(type, records);
-                    break;
+                    throw new InvalidOperationException("Cannot set records in stub zone.");
             }
         }
 
         public override void AddRecord(DnsResourceRecord record)
         {
-            switch (record.Type)
-            {
-                case DnsResourceRecordType.NS:
-                    throw new InvalidOperationException("Cannot add NS record at stub zone root.");
-
-                default:
-                    base.AddRecord(record);
-                    break;
-            }
+            throw new InvalidOperationException("Cannot add record in stub zone.");
         }
 
         public override bool DeleteRecords(DnsResourceRecordType type)
         {
-            switch (type)
-            {
-                case DnsResourceRecordType.NS:
-                    throw new InvalidOperationException("Cannot delete NS records in stub zone root.");
-
-                case DnsResourceRecordType.SOA:
-                    throw new InvalidOperationException("Cannot delete SOA record.");
-
-                default:
-                    return base.DeleteRecords(type);
-            }
+            throw new InvalidOperationException("Cannot delete record in stub zone.");
         }
 
         public override bool DeleteRecord(DnsResourceRecordType type, DnsResourceRecordData record)
         {
-            switch (type)
-            {
-                case DnsResourceRecordType.NS:
-                    throw new InvalidOperationException("Cannot delete NS record in stub zone root.");
-
-                case DnsResourceRecordType.SOA:
-                    throw new InvalidOperationException("Cannot delete SOA record.");
-
-                default:
-                    return base.DeleteRecord(type, record);
-            }
+            throw new InvalidOperationException("Cannot delete records in stub zone.");
         }
 
         public override IReadOnlyList<DnsResourceRecord> QueryRecords(DnsResourceRecordType type)
         {
-            switch (type)
-            {
-                case DnsResourceRecordType.SOA:
-                case DnsResourceRecordType.NS:
-                    return Array.Empty<DnsResourceRecord>(); //stub zone has no authority so cant return NS or SOA records as query response
-
-                default:
-                    return base.QueryRecords(type);
-            }
+            return Array.Empty<DnsResourceRecord>(); //stub zone has no authority so cant return any records as query response to allow generating referral response
         }
 
         #endregion