added AllowedZoneManager

DnsServerCore/Dns/ZoneManagers/AllowedZoneManager.cs

@@ -0,0 +1,190 @@
+/*
+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/>.
+
+*/
+
+using DnsServerCore.Dns.Zones;
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Security.Cryptography;
+using System.Text;
+using TechnitiumLibrary.IO;
+using TechnitiumLibrary.Net.Dns;
+using TechnitiumLibrary.Net.Dns.ResourceRecords;
+
+namespace DnsServerCore.Dns.ZoneManagers
+{
+    public class AllowedZoneManager
+    {
+        #region variables
+
+        readonly DnsServer _dnsServer;
+
+        readonly AuthZoneManager _zoneManager = new AuthZoneManager(null);
+
+        DnsSOARecord _soaRecord;
+        DnsNSRecord _nsRecord;
+
+        int _totalZonesAllowed;
+
+        #endregion
+
+        #region constructor
+
+        public AllowedZoneManager(DnsServer dnsServer)
+        {
+            _dnsServer = dnsServer;
+
+            UpdateServerDomain(_dnsServer.ServerDomain);
+            LoadZoneFile();
+        }
+
+        #endregion
+
+        #region private
+
+        private void UpdateServerDomain(string serverDomain)
+        {
+            _soaRecord = new DnsSOARecord(serverDomain, "hostmaster." + serverDomain, 1, 14400, 3600, 604800, 900);
+            _nsRecord = new DnsNSRecord(serverDomain);
+        }
+
+        private void LoadZoneFile()
+        {
+            string allowedZoneFile = Path.Combine(_dnsServer.ConfigFolder, "allowed.config");
+
+            try
+            {
+                LogManager log = _dnsServer.LogManager;
+                if (log != null)
+                    log.Write("DNS Server is loading allowed zone file: " + allowedZoneFile);
+
+                using (FileStream fS = new FileStream(allowedZoneFile, FileMode.Open, FileAccess.Read))
+                {
+                    BinaryReader bR = new BinaryReader(fS);
+
+                    if (Encoding.ASCII.GetString(bR.ReadBytes(2)) != "AZ") //format
+                        throw new InvalidDataException("DnsServer allowed zone file format is invalid.");
+
+                    byte version = bR.ReadByte();
+                    switch (version)
+                    {
+                        case 1:
+                            int length = bR.ReadInt32();
+
+                            for (int i = 0; i < length; i++)
+                                AllowZone(bR.ReadShortString());
+
+                            break;
+
+                        default:
+                            throw new InvalidDataException("DnsServer allowed zone file version not supported.");
+                    }
+                }
+
+                if (log != null)
+                    log.Write("DNS Server allowed zone file was loaded: " + allowedZoneFile);
+            }
+            catch (FileNotFoundException)
+            { }
+            catch (Exception ex)
+            {
+                LogManager log = _dnsServer.LogManager;
+                if (log != null)
+                    log.Write("DNS Server encountered an error while loading allowed zone file: " + allowedZoneFile + "\r\n" + ex.ToString());
+            }
+        }
+
+        #endregion
+
+        #region public
+
+        public void AllowZone(string domain)
+        {
+            if (_zoneManager.CreatePrimaryZone(domain, _soaRecord, _nsRecord, false) != null)
+                _totalZonesAllowed++;
+        }
+
+        public void DeleteZone(string domain)
+        {
+            if (_zoneManager.DeleteZone(domain))
+                _totalZonesAllowed--;
+        }
+
+        public List<AuthZoneInfo> ListZones()
+        {
+            return _zoneManager.ListZones();
+        }
+
+        public List<string> ListSubDomains(string domain)
+        {
+            return _zoneManager.ListSubDomains(domain);
+        }
+
+        public IReadOnlyList<DnsResourceRecord> QueryRecords(string domain, DnsResourceRecordType type)
+        {
+            return _zoneManager.QueryRecords(domain, type);
+        }
+
+        public void SaveZoneFile()
+        {
+            List<AuthZoneInfo> allowedZones = _dnsServer.AllowedZoneManager.ListZones();
+
+            _totalZonesAllowed = allowedZones.Count;
+
+            string allowedZoneFile = Path.Combine(_dnsServer.ConfigFolder, "allowed.config");
+
+            using (FileStream fS = new FileStream(allowedZoneFile, FileMode.Create, FileAccess.Write))
+            {
+                BinaryWriter bW = new BinaryWriter(fS);
+
+                bW.Write(Encoding.ASCII.GetBytes("AZ")); //format
+                bW.Write((byte)1); //version
+
+                bW.Write(allowedZones.Count);
+
+                foreach (AuthZoneInfo zone in allowedZones)
+                    bW.WriteShortString(zone.Name);
+            }
+
+            LogManager log = _dnsServer.LogManager;
+            if (log != null)
+                log.Write("DNS Server allowed zone file was saved: " + allowedZoneFile);
+        }
+
+        public DnsDatagram Query(DnsDatagram request)
+        {
+            return _zoneManager.Query(request);
+        }
+
+        #endregion
+
+        #region properties
+
+        public string ServerDomain
+        {
+            get { return _soaRecord.MasterNameServer; }
+            set { UpdateServerDomain(value); }
+        }
+
+        public int TotalZonesAllowed
+        { get { return _totalZonesAllowed; } }
+
+        #endregion
+    }
+}