mirror of
https://github.com/fergalmoran/DnsServer.git
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1071 lines
40 KiB
C#
1071 lines
40 KiB
C#
/*
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Technitium DNS Server
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Copyright (C) 2019 Shreyas Zare (shreyas@technitium.com)
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This program is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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using DnsServerCore.Dhcp.Options;
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using DnsServerCore.Dns;
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using System;
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using System.Collections.Concurrent;
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using System.Collections.Generic;
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using System.IO;
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using System.Net;
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using System.Net.Sockets;
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using System.Threading;
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using TechnitiumLibrary.Net.Dns;
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using TechnitiumLibrary.Net.Dns.ResourceRecords;
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namespace DnsServerCore.Dhcp
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{
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//Dynamic Host Configuration Protocol
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//https://tools.ietf.org/html/rfc2131
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//DHCP Options and BOOTP Vendor Extensions
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//https://tools.ietf.org/html/rfc2132
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//Encoding Long Options in the Dynamic Host Configuration Protocol (DHCPv4)
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//https://tools.ietf.org/html/rfc3396
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//Client Fully Qualified Domain Name(FQDN) Option
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//https://tools.ietf.org/html/rfc4702
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public class DhcpServer : IDisposable
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{
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#region enum
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enum ServiceState
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{
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Stopped = 0,
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Starting = 1,
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Running = 2,
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Stopping = 3
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}
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#endregion
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#region variables
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readonly string _configFolder;
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readonly ConcurrentDictionary<IPAddress, Socket> _udpListeners = new ConcurrentDictionary<IPAddress, Socket>();
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readonly List<Thread> _listenerThreads = new List<Thread>();
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readonly ConcurrentDictionary<string, Scope> _scopes = new ConcurrentDictionary<string, Scope>();
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Zone _authoritativeZoneRoot;
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LogManager _log;
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volatile ServiceState _state = ServiceState.Stopped;
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readonly IPEndPoint _dhcpDefaultEP = new IPEndPoint(IPAddress.Any, 67);
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Timer _maintenanceTimer;
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const int MAINTENANCE_TIMER_INTERVAL = 10000;
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DateTime _lastModifiedScopesSavedOn;
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#endregion
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#region constructor
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public DhcpServer(string configFolder)
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{
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_configFolder = configFolder;
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if (!Directory.Exists(_configFolder))
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Directory.CreateDirectory(_configFolder);
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}
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#endregion
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#region IDisposable
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private bool _disposed = false;
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protected virtual void Dispose(bool disposing)
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{
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if (_disposed)
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return;
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if (disposing)
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{
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Stop();
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if (_maintenanceTimer != null)
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_maintenanceTimer.Dispose();
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SaveModifiedScopes();
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}
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_disposed = true;
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}
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public void Dispose()
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{
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Dispose(true);
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}
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#endregion
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#region private
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private void ReadUdpRequestAsync(object parameter)
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{
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Socket udpListener = parameter as Socket;
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EndPoint remoteEP = new IPEndPoint(IPAddress.Any, 0);
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byte[] recvBuffer = new byte[576];
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int bytesRecv;
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bool processOnlyUnicastMessages = !(udpListener.LocalEndPoint as IPEndPoint).Address.Equals(IPAddress.Any); //only 0.0.0.0 ip should process broadcast to avoid duplicate offers on Windows
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try
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{
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while (true)
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{
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SocketFlags flags = SocketFlags.None;
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IPPacketInformation ipPacketInformation;
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try
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{
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bytesRecv = udpListener.ReceiveMessageFrom(recvBuffer, 0, recvBuffer.Length, ref flags, ref remoteEP, out ipPacketInformation);
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}
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catch (SocketException ex)
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{
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switch (ex.SocketErrorCode)
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{
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case SocketError.ConnectionReset:
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case SocketError.HostUnreachable:
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case SocketError.MessageSize:
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case SocketError.NetworkReset:
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bytesRecv = 0;
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break;
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default:
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throw;
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}
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}
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if (bytesRecv > 0)
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{
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if (processOnlyUnicastMessages && ipPacketInformation.Address.Equals(IPAddress.Broadcast))
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continue;
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switch ((remoteEP as IPEndPoint).Port)
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{
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case 67:
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case 68:
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try
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{
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ThreadPool.QueueUserWorkItem(ProcessUdpRequestAsync, new object[] { udpListener, remoteEP, ipPacketInformation, new DhcpMessage(new MemoryStream(recvBuffer, 0, bytesRecv, false)) });
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}
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catch (Exception ex)
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{
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LogManager log = _log;
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if (log != null)
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log.Write(remoteEP as IPEndPoint, ex);
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}
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break;
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}
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}
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}
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}
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catch (SocketException ex)
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{
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switch (ex.SocketErrorCode)
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{
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case SocketError.Interrupted:
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break; //server stopping
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default:
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LogManager log = _log;
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if (log != null)
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log.Write(remoteEP as IPEndPoint, ex);
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throw;
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}
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}
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catch (Exception ex)
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{
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if ((_state == ServiceState.Stopping) || (_state == ServiceState.Stopped))
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return; //server stopping
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LogManager log = _log;
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if (log != null)
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log.Write(remoteEP as IPEndPoint, ex);
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throw;
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}
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}
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private void ProcessUdpRequestAsync(object parameter)
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{
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object[] parameters = parameter as object[];
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Socket udpListener = parameters[0] as Socket;
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EndPoint remoteEP = parameters[1] as EndPoint;
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IPPacketInformation ipPacketInformation = (IPPacketInformation)parameters[2];
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DhcpMessage request = parameters[3] as DhcpMessage;
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try
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{
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DhcpMessage response = ProcessDhcpMessage(request, remoteEP as IPEndPoint, ipPacketInformation);
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//send response
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if (response != null)
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{
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byte[] sendBuffer = new byte[512];
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MemoryStream sendBufferStream = new MemoryStream(sendBuffer);
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response.WriteTo(sendBufferStream);
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//send dns datagram
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if (!request.RelayAgentIpAddress.Equals(IPAddress.Any))
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{
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//received request via relay agent so send unicast response to relay agent on port 67
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udpListener.SendTo(sendBuffer, 0, (int)sendBufferStream.Position, SocketFlags.None, new IPEndPoint(request.RelayAgentIpAddress, 67));
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}
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else if (!request.ClientIpAddress.Equals(IPAddress.Any))
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{
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//client is already configured and renewing lease so send unicast response on port 68
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udpListener.SendTo(sendBuffer, 0, (int)sendBufferStream.Position, SocketFlags.None, new IPEndPoint(request.ClientIpAddress, 68));
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}
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else
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{
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//send response as broadcast on port 68 on appropriate interface bound socket
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if (!_udpListeners.TryGetValue(response.NextServerIpAddress, out Socket udpSocket))
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udpSocket = udpListener; //no appropriate socket found so use default socket
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udpSocket.SendTo(sendBuffer, 0, (int)sendBufferStream.Position, SocketFlags.None, new IPEndPoint(IPAddress.Broadcast, 68));
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}
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}
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}
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catch (Exception ex)
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{
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if ((_state == ServiceState.Stopping) || (_state == ServiceState.Stopped))
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return; //server stopping
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LogManager log = _log;
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if (log != null)
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log.Write(remoteEP as IPEndPoint, ex);
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}
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}
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private DhcpMessage ProcessDhcpMessage(DhcpMessage request, IPEndPoint remoteEP, IPPacketInformation ipPacketInformation)
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{
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if (request.OpCode != DhcpMessageOpCode.BootRequest)
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return null;
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switch (request.DhcpMessageType?.Type)
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{
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case DhcpMessageType.Discover:
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{
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Scope scope = FindScope(request, remoteEP.Address, ipPacketInformation);
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if (scope == null)
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return null; //no scope available; do nothing
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if (scope.OfferDelayTime > 0)
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Thread.Sleep(scope.OfferDelayTime); //delay sending offer
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Lease offer = scope.GetOffer(request);
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if (offer == null)
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throw new DhcpServerException("DHCP Server failed to offer address: address unavailable due to address pool exhaustion.");
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List<DhcpOption> options = scope.GetOptions(request, scope.InterfaceAddress);
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if (options == null)
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return null;
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//log ip offer
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LogManager log = _log;
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if (log != null)
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log.Write(remoteEP as IPEndPoint, "DHCP Server offered IP address [" + offer.Address.ToString() + "] to " + request.GetClientFullIdentifier() + ".");
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return new DhcpMessage(request, offer.Address, scope.InterfaceAddress, options);
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}
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case DhcpMessageType.Request:
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{
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//request ip address lease or extend existing lease
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Scope scope = FindScope(request, remoteEP.Address, ipPacketInformation);
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if (scope == null)
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return null; //no scope available; do nothing
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Lease leaseOffer;
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if (request.ServerIdentifier == null)
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{
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if (request.RequestedIpAddress == null)
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{
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//renewing or rebinding
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if (request.ClientIpAddress.Equals(IPAddress.Any))
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return null; //client must set IP address in ciaddr; do nothing
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leaseOffer = scope.GetExistingLeaseOrOffer(request);
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if (leaseOffer == null)
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{
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//no existing lease or offer available for client
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//send nak
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return new DhcpMessage(request, IPAddress.Any, scope.InterfaceAddress, new DhcpOption[] { new DhcpMessageTypeOption(DhcpMessageType.Nak), new ServerIdentifierOption(scope.InterfaceAddress), DhcpOption.CreateEndOption() });
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}
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if (!request.ClientIpAddress.Equals(leaseOffer.Address))
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{
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//client ip is incorrect
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//send nak
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return new DhcpMessage(request, IPAddress.Any, scope.InterfaceAddress, new DhcpOption[] { new DhcpMessageTypeOption(DhcpMessageType.Nak), new ServerIdentifierOption(scope.InterfaceAddress), DhcpOption.CreateEndOption() });
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}
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}
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else
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{
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//init-reboot
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leaseOffer = scope.GetExistingLeaseOrOffer(request);
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if (leaseOffer == null)
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{
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//no existing lease or offer available for client
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//send nak
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return new DhcpMessage(request, IPAddress.Any, scope.InterfaceAddress, new DhcpOption[] { new DhcpMessageTypeOption(DhcpMessageType.Nak), new ServerIdentifierOption(scope.InterfaceAddress), DhcpOption.CreateEndOption() });
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}
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if (!request.RequestedIpAddress.Address.Equals(leaseOffer.Address))
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{
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//the client's notion of its IP address is not correct - RFC 2131
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//send nak
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return new DhcpMessage(request, IPAddress.Any, scope.InterfaceAddress, new DhcpOption[] { new DhcpMessageTypeOption(DhcpMessageType.Nak), new ServerIdentifierOption(scope.InterfaceAddress), DhcpOption.CreateEndOption() });
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}
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}
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}
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else
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{
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//selecting offer
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if (request.RequestedIpAddress == null)
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return null; //client MUST include this option; do nothing
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if (!request.ServerIdentifier.Address.Equals(scope.InterfaceAddress))
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return null; //offer declined by client; do nothing
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leaseOffer = scope.GetExistingLeaseOrOffer(request);
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if (leaseOffer == null)
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{
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//no existing lease or offer available for client
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//send nak
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return new DhcpMessage(request, IPAddress.Any, scope.InterfaceAddress, new DhcpOption[] { new DhcpMessageTypeOption(DhcpMessageType.Nak), new ServerIdentifierOption(scope.InterfaceAddress), DhcpOption.CreateEndOption() });
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}
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if (!request.RequestedIpAddress.Address.Equals(leaseOffer.Address))
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{
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//requested ip is incorrect
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//send nak
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return new DhcpMessage(request, IPAddress.Any, scope.InterfaceAddress, new DhcpOption[] { new DhcpMessageTypeOption(DhcpMessageType.Nak), new ServerIdentifierOption(scope.InterfaceAddress), DhcpOption.CreateEndOption() });
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}
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}
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List<DhcpOption> options = scope.GetOptions(request, scope.InterfaceAddress);
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if (options == null)
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return null;
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scope.CommitLease(leaseOffer);
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//log ip lease
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LogManager log = _log;
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if (log != null)
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log.Write(remoteEP as IPEndPoint, "DHCP Server leased IP address [" + leaseOffer.Address.ToString() + "] to " + request.GetClientFullIdentifier() + ".");
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if (!string.IsNullOrEmpty(scope.DomainName))
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{
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//update dns
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string clientDomainName = null;
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foreach (DhcpOption option in options)
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{
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if (option.Code == DhcpOptionCode.ClientFullyQualifiedDomainName)
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{
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clientDomainName = (option as ClientFullyQualifiedDomainNameOption).DomainName;
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break;
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}
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}
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if (clientDomainName == null)
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{
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if (request.HostName != null)
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clientDomainName = request.HostName.HostName + "." + scope.DomainName;
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}
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if (clientDomainName != null)
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{
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leaseOffer.SetHostName(clientDomainName.ToLower());
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UpdateDnsAuthZone(true, scope, leaseOffer);
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}
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}
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return new DhcpMessage(request, leaseOffer.Address, scope.InterfaceAddress, options);
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}
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case DhcpMessageType.Decline:
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{
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//ip address is already in use as detected by client via ARP
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if ((request.ServerIdentifier == null) || (request.RequestedIpAddress == null))
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return null; //client MUST include these option; do nothing
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Scope scope = FindScope(request, remoteEP.Address, ipPacketInformation);
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if (scope == null)
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return null; //no scope available; do nothing
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if (!request.ServerIdentifier.Address.Equals(scope.InterfaceAddress))
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return null; //request not for this server; do nothing
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Lease lease = scope.GetExistingLeaseOrOffer(request);
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if (lease == null)
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return null; //no existing lease or offer available for client; do nothing
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if (!lease.Address.Equals(request.RequestedIpAddress.Address))
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return null; //the client's notion of its IP address is not correct; do nothing
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//remove lease since the IP address is used by someone else
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scope.ReleaseLease(lease);
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//log issue
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LogManager log = _log;
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if (log != null)
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log.Write(remoteEP as IPEndPoint, "DHCP Server received DECLINE message: " + lease.GetClientFullIdentifier() + " detected that IP address [" + lease.Address + "] is already in use.");
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//update dns
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UpdateDnsAuthZone(false, scope, lease);
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//do nothing
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return null;
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}
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case DhcpMessageType.Release:
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{
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//cancel ip address lease
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if (request.ServerIdentifier == null)
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return null; //client MUST include this option; do nothing
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Scope scope = FindScope(request, remoteEP.Address, ipPacketInformation);
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if (scope == null)
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return null; //no scope available; do nothing
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if (!request.ServerIdentifier.Address.Equals(scope.InterfaceAddress))
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return null; //request not for this server; do nothing
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Lease lease = scope.GetExistingLeaseOrOffer(request);
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if (lease == null)
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return null; //no existing lease or offer available for client; do nothing
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if (!lease.Address.Equals(request.ClientIpAddress))
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return null; //the client's notion of its IP address is not correct; do nothing
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//release lease
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scope.ReleaseLease(lease);
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//log ip lease release
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LogManager log = _log;
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if (log != null)
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log.Write(remoteEP as IPEndPoint, "DHCP Server released IP address [" + lease.Address.ToString() + "] that was leased to " + lease.GetClientFullIdentifier() + ".");
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//update dns
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UpdateDnsAuthZone(false, scope, lease);
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//do nothing
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return null;
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}
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case DhcpMessageType.Inform:
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{
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//need only local config; already has ip address assigned externally/manually
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Scope scope = FindScope(request, remoteEP.Address, ipPacketInformation);
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if (scope == null)
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return null; //no scope available; do nothing
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List<DhcpOption> options = scope.GetOptions(request, scope.InterfaceAddress);
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if (options == null)
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return null;
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//log inform
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LogManager log = _log;
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if (log != null)
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log.Write(remoteEP as IPEndPoint, "DHCP Server received INFORM message from " + request.GetClientFullIdentifier() + ".");
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return new DhcpMessage(request, IPAddress.Any, scope.InterfaceAddress, options);
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}
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default:
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return null;
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}
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}
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private Scope FindScope(DhcpMessage request, IPAddress remoteAddress, IPPacketInformation ipPacketInformation)
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{
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bool broadcast;
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if (request.RelayAgentIpAddress.Equals(IPAddress.Any))
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{
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//no relay agent
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if (request.ClientIpAddress.Equals(IPAddress.Any))
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{
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if (!ipPacketInformation.Address.Equals(IPAddress.Broadcast))
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return null; //message destination address must be broadcast address
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broadcast = true; //broadcast request
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}
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else
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{
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if (!remoteAddress.Equals(request.ClientIpAddress))
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return null; //client ip must match udp src addr
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broadcast = false; //unicast request
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}
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}
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else
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{
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//relay agent unicast
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if (!remoteAddress.Equals(request.RelayAgentIpAddress))
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return null; //relay ip must match udp src addr
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broadcast = false; //unicast request
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}
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if (broadcast)
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{
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foreach (KeyValuePair<string, Scope> scope in _scopes)
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{
|
|
if (scope.Value.Enabled && (scope.Value.InterfaceIndex == ipPacketInformation.Interface))
|
|
return scope.Value;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
foreach (KeyValuePair<string, Scope> scope in _scopes)
|
|
{
|
|
if (scope.Value.Enabled && (scope.Value.IsAddressInRange(remoteAddress)))
|
|
return scope.Value;
|
|
}
|
|
}
|
|
|
|
return null;
|
|
}
|
|
|
|
private void UpdateDnsAuthZone(bool add, Scope scope, Lease lease)
|
|
{
|
|
if (_authoritativeZoneRoot == null)
|
|
return;
|
|
|
|
if (string.IsNullOrEmpty(scope.DomainName))
|
|
return;
|
|
|
|
if (add)
|
|
{
|
|
//update forward zone
|
|
if (!string.IsNullOrEmpty(scope.DomainName))
|
|
{
|
|
if (!_authoritativeZoneRoot.ZoneExists(scope.DomainName))
|
|
{
|
|
//create forward zone
|
|
_authoritativeZoneRoot.SetRecords(scope.DomainName, DnsResourceRecordType.SOA, 14400, new DnsResourceRecordData[] { new DnsSOARecord(_authoritativeZoneRoot.ServerDomain, "hostmaster." + scope.DomainName, uint.Parse(DateTime.UtcNow.ToString("yyyyMMddHH")), 28800, 7200, 604800, 600) });
|
|
_authoritativeZoneRoot.SetRecords(scope.DomainName, DnsResourceRecordType.NS, 14400, new DnsResourceRecordData[] { new DnsNSRecord(_authoritativeZoneRoot.ServerDomain) });
|
|
|
|
_authoritativeZoneRoot.MakeZoneInternal(scope.DomainName);
|
|
}
|
|
|
|
_authoritativeZoneRoot.SetRecords(lease.HostName, DnsResourceRecordType.A, scope.DnsTtl, new DnsResourceRecordData[] { new DnsARecord(lease.Address) });
|
|
}
|
|
|
|
//update reverse zone
|
|
{
|
|
if (!_authoritativeZoneRoot.ZoneExists(scope.ReverseZone))
|
|
{
|
|
//create reverse zone
|
|
_authoritativeZoneRoot.SetRecords(scope.ReverseZone, DnsResourceRecordType.SOA, 14400, new DnsResourceRecordData[] { new DnsSOARecord(_authoritativeZoneRoot.ServerDomain, "hostmaster." + scope.ReverseZone, uint.Parse(DateTime.UtcNow.ToString("yyyyMMddHH")), 28800, 7200, 604800, 600) });
|
|
_authoritativeZoneRoot.SetRecords(scope.ReverseZone, DnsResourceRecordType.NS, 14400, new DnsResourceRecordData[] { new DnsNSRecord(_authoritativeZoneRoot.ServerDomain) });
|
|
|
|
_authoritativeZoneRoot.MakeZoneInternal(scope.ReverseZone);
|
|
}
|
|
|
|
_authoritativeZoneRoot.SetRecords(Scope.GetReverseZone(lease.Address, 32), DnsResourceRecordType.PTR, scope.DnsTtl, new DnsResourceRecordData[] { new DnsPTRRecord(lease.HostName) });
|
|
}
|
|
}
|
|
else
|
|
{
|
|
//remove from forward zone
|
|
_authoritativeZoneRoot.DeleteRecords(lease.HostName, DnsResourceRecordType.A);
|
|
|
|
//remove from reverse zone
|
|
_authoritativeZoneRoot.DeleteRecords(Scope.GetReverseZone(lease.Address, 32), DnsResourceRecordType.PTR);
|
|
}
|
|
}
|
|
|
|
private void BindUdpListener(IPEndPoint dhcpEP)
|
|
{
|
|
Socket udpListener = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
|
|
|
|
try
|
|
{
|
|
#region this code ignores ICMP port unreachable responses which creates SocketException in ReceiveFrom()
|
|
|
|
if (Environment.OSVersion.Platform == PlatformID.Win32NT)
|
|
{
|
|
const uint IOC_IN = 0x80000000;
|
|
const uint IOC_VENDOR = 0x18000000;
|
|
const uint SIO_UDP_CONNRESET = IOC_IN | IOC_VENDOR | 12;
|
|
|
|
udpListener.IOControl((IOControlCode)SIO_UDP_CONNRESET, new byte[] { Convert.ToByte(false) }, null);
|
|
}
|
|
|
|
#endregion
|
|
|
|
//bind to interface address
|
|
if (Environment.OSVersion.Platform == PlatformID.Unix)
|
|
udpListener.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, 1); //to allow binding to same port with different addresses
|
|
|
|
udpListener.EnableBroadcast = true;
|
|
udpListener.ExclusiveAddressUse = false;
|
|
|
|
udpListener.Bind(dhcpEP);
|
|
|
|
if (!_udpListeners.TryAdd(dhcpEP.Address, udpListener))
|
|
throw new DhcpServerException("Udp listener already exists for IP address: " + dhcpEP.Address);
|
|
|
|
//start reading dhcp packets
|
|
Thread listenerThread = new Thread(ReadUdpRequestAsync);
|
|
listenerThread.IsBackground = true;
|
|
listenerThread.Start(udpListener);
|
|
|
|
lock (_listenerThreads)
|
|
{
|
|
_listenerThreads.Add(listenerThread);
|
|
}
|
|
}
|
|
catch
|
|
{
|
|
udpListener.Dispose();
|
|
throw;
|
|
}
|
|
}
|
|
|
|
private bool UnbindUdpListener(IPEndPoint dhcpEP)
|
|
{
|
|
if (_udpListeners.TryRemove(dhcpEP.Address, out Socket socket))
|
|
{
|
|
socket.Dispose();
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
private bool ActivateScope(Scope scope)
|
|
{
|
|
IPEndPoint dhcpEP = null;
|
|
|
|
try
|
|
{
|
|
//find scope interface for binding socket
|
|
scope.FindInterface();
|
|
|
|
IPAddress interfaceAddress = scope.InterfaceAddress;
|
|
dhcpEP = new IPEndPoint(interfaceAddress, 67);
|
|
|
|
if (!interfaceAddress.Equals(IPAddress.Any))
|
|
BindUdpListener(dhcpEP);
|
|
|
|
if (_authoritativeZoneRoot != null)
|
|
{
|
|
//update valid leases into dns
|
|
DateTime utcNow = DateTime.UtcNow;
|
|
|
|
foreach (Lease lease in scope.Leases)
|
|
{
|
|
if (utcNow < lease.LeaseExpires)
|
|
UpdateDnsAuthZone(true, scope, lease); //lease valid
|
|
}
|
|
}
|
|
|
|
LogManager log = _log;
|
|
if (log != null)
|
|
log.Write(dhcpEP, "DHCP Server successfully activated scope: " + scope.Name);
|
|
|
|
return true;
|
|
}
|
|
catch (Exception ex)
|
|
{
|
|
LogManager log = _log;
|
|
if (log != null)
|
|
log.Write(dhcpEP, "DHCP Server failed to activate scope: " + scope.Name + "\r\n" + ex.ToString());
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
private bool DeactivateScope(Scope scope)
|
|
{
|
|
IPEndPoint dhcpEP = null;
|
|
|
|
try
|
|
{
|
|
IPAddress interfaceAddress = scope.InterfaceAddress;
|
|
dhcpEP = new IPEndPoint(interfaceAddress, 67);
|
|
|
|
if (!interfaceAddress.Equals(IPAddress.Any))
|
|
UnbindUdpListener(dhcpEP);
|
|
|
|
if (_authoritativeZoneRoot != null)
|
|
{
|
|
//remove all leases from dns
|
|
foreach (Lease lease in scope.Leases)
|
|
UpdateDnsAuthZone(false, scope, lease);
|
|
}
|
|
|
|
LogManager log = _log;
|
|
if (log != null)
|
|
log.Write(dhcpEP, "DHCP Server successfully deactivated scope: " + scope.Name);
|
|
|
|
return true;
|
|
}
|
|
catch (Exception ex)
|
|
{
|
|
LogManager log = _log;
|
|
if (log != null)
|
|
log.Write(dhcpEP, "DHCP Server failed to deactivate scope: " + scope.Name + "\r\n" + ex.ToString());
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
private void LoadScope(Scope scope)
|
|
{
|
|
foreach (KeyValuePair<string, Scope> existingScope in _scopes)
|
|
{
|
|
if (existingScope.Value.Equals(scope))
|
|
throw new DhcpServerException("Scope with same range already exists.");
|
|
}
|
|
|
|
if (!_scopes.TryAdd(scope.Name, scope))
|
|
throw new DhcpServerException("Scope with same name already exists.");
|
|
|
|
if (scope.Enabled)
|
|
ActivateScope(scope);
|
|
|
|
LogManager log = _log;
|
|
if (log != null)
|
|
log.Write("DHCP Server successfully loaded scope: " + scope.Name);
|
|
}
|
|
|
|
private void UnloadScope(Scope scope)
|
|
{
|
|
if (scope.Enabled)
|
|
DeactivateScope(scope);
|
|
|
|
if (_scopes.TryRemove(scope.Name, out _))
|
|
{
|
|
LogManager log = _log;
|
|
if (log != null)
|
|
log.Write("DHCP Server successfully unloaded scope: " + scope.Name);
|
|
}
|
|
}
|
|
|
|
private void LoadAllScopeFiles()
|
|
{
|
|
string[] scopeFiles = Directory.GetFiles(_configFolder, "*.scope");
|
|
|
|
foreach (string scopeFile in scopeFiles)
|
|
LoadScopeFile(scopeFile);
|
|
|
|
_lastModifiedScopesSavedOn = DateTime.UtcNow;
|
|
}
|
|
|
|
private void LoadScopeFile(string scopeFile)
|
|
{
|
|
try
|
|
{
|
|
using (FileStream fS = new FileStream(scopeFile, FileMode.Open, FileAccess.Read))
|
|
{
|
|
LoadScope(new Scope(new BinaryReader(fS)));
|
|
}
|
|
|
|
LogManager log = _log;
|
|
if (log != null)
|
|
log.Write("DHCP Server successfully loaded scope file: " + scopeFile);
|
|
}
|
|
catch (Exception ex)
|
|
{
|
|
LogManager log = _log;
|
|
if (log != null)
|
|
log.Write("DHCP Server failed to load scope file: " + scopeFile + "\r\n" + ex.ToString());
|
|
}
|
|
}
|
|
|
|
private void SaveScopeFile(Scope scope)
|
|
{
|
|
string scopeFile = Path.Combine(_configFolder, scope.Name + ".scope");
|
|
|
|
try
|
|
{
|
|
using (FileStream fS = new FileStream(scopeFile, FileMode.Create, FileAccess.Write))
|
|
{
|
|
scope.WriteTo(new BinaryWriter(fS));
|
|
}
|
|
|
|
LogManager log = _log;
|
|
if (log != null)
|
|
log.Write("DHCP Server successfully saved scope file: " + scopeFile);
|
|
}
|
|
catch (Exception ex)
|
|
{
|
|
LogManager log = _log;
|
|
if (log != null)
|
|
log.Write("DHCP Server failed to save scope file: " + scopeFile + "\r\n" + ex.ToString());
|
|
}
|
|
}
|
|
|
|
private void DeleteScopeFile(string scopeName)
|
|
{
|
|
string scopeFile = Path.Combine(_configFolder, scopeName + ".scope");
|
|
|
|
try
|
|
{
|
|
File.Delete(scopeFile);
|
|
|
|
LogManager log = _log;
|
|
if (log != null)
|
|
log.Write("DHCP Server successfully deleted scope file: " + scopeFile);
|
|
}
|
|
catch (Exception ex)
|
|
{
|
|
LogManager log = _log;
|
|
if (log != null)
|
|
log.Write("DHCP Server failed to delete scope file: " + scopeFile + "\r\n" + ex.ToString());
|
|
}
|
|
}
|
|
|
|
private void SaveModifiedScopes()
|
|
{
|
|
DateTime currentDateTime = DateTime.UtcNow;
|
|
|
|
foreach (KeyValuePair<string, Scope> scope in _scopes)
|
|
{
|
|
if (scope.Value.LastModified > _lastModifiedScopesSavedOn)
|
|
SaveScopeFile(scope.Value);
|
|
}
|
|
|
|
_lastModifiedScopesSavedOn = currentDateTime;
|
|
}
|
|
|
|
private void StartMaintenanceTimer()
|
|
{
|
|
if (_maintenanceTimer == null)
|
|
{
|
|
_maintenanceTimer = new Timer(delegate (object state)
|
|
{
|
|
try
|
|
{
|
|
foreach (KeyValuePair<string, Scope> scope in _scopes)
|
|
{
|
|
scope.Value.RemoveExpiredOffers();
|
|
|
|
List<Lease> expiredLeases = scope.Value.RemoveExpiredLeases();
|
|
|
|
foreach (Lease expiredLease in expiredLeases)
|
|
UpdateDnsAuthZone(false, scope.Value, expiredLease);
|
|
}
|
|
|
|
SaveModifiedScopes();
|
|
}
|
|
catch (Exception ex)
|
|
{
|
|
LogManager log = _log;
|
|
if (log != null)
|
|
log.Write(ex);
|
|
}
|
|
finally
|
|
{
|
|
if (!_disposed)
|
|
_maintenanceTimer.Change(MAINTENANCE_TIMER_INTERVAL, Timeout.Infinite);
|
|
}
|
|
}, null, Timeout.Infinite, Timeout.Infinite);
|
|
}
|
|
|
|
_maintenanceTimer.Change(MAINTENANCE_TIMER_INTERVAL, Timeout.Infinite);
|
|
}
|
|
|
|
private void StopMaintenanceTimer()
|
|
{
|
|
_maintenanceTimer.Change(Timeout.Infinite, Timeout.Infinite);
|
|
}
|
|
|
|
#endregion
|
|
|
|
#region public
|
|
|
|
public void Start()
|
|
{
|
|
if (_disposed)
|
|
throw new ObjectDisposedException("DhcpServer");
|
|
|
|
if (_state != ServiceState.Stopped)
|
|
throw new InvalidOperationException("DHCP Server is already running.");
|
|
|
|
_state = ServiceState.Starting;
|
|
|
|
BindUdpListener(_dhcpDefaultEP);
|
|
|
|
LoadAllScopeFiles();
|
|
StartMaintenanceTimer();
|
|
|
|
_state = ServiceState.Running;
|
|
}
|
|
|
|
public void Stop()
|
|
{
|
|
if (_state != ServiceState.Running)
|
|
return;
|
|
|
|
_state = ServiceState.Stopping;
|
|
|
|
StopMaintenanceTimer();
|
|
|
|
UnbindUdpListener(_dhcpDefaultEP);
|
|
|
|
foreach (KeyValuePair<string, Scope> scope in _scopes)
|
|
UnloadScope(scope.Value);
|
|
|
|
_listenerThreads.Clear();
|
|
_udpListeners.Clear();
|
|
|
|
_state = ServiceState.Stopped;
|
|
}
|
|
|
|
public void AddScope(Scope scope)
|
|
{
|
|
LoadScope(scope);
|
|
SaveScopeFile(scope);
|
|
}
|
|
|
|
public Scope GetScope(string name)
|
|
{
|
|
if (_scopes.TryGetValue(name, out Scope scope))
|
|
return scope;
|
|
|
|
return null;
|
|
}
|
|
|
|
public void RenameScope(string oldName, string newName)
|
|
{
|
|
if (!_scopes.TryGetValue(oldName, out Scope scope))
|
|
throw new DhcpServerException("Scope with name '" + oldName + "' does not exists.");
|
|
|
|
if (!_scopes.TryAdd(newName, scope))
|
|
throw new DhcpServerException("Scope with name '" + newName + "' already exists.");
|
|
|
|
scope.Name = newName;
|
|
_scopes.TryRemove(oldName, out _);
|
|
|
|
SaveScopeFile(scope);
|
|
DeleteScopeFile(oldName);
|
|
}
|
|
|
|
public void DeleteScope(string name)
|
|
{
|
|
if (_scopes.TryGetValue(name, out Scope scope))
|
|
{
|
|
UnloadScope(scope);
|
|
DeleteScopeFile(scope.Name);
|
|
}
|
|
}
|
|
|
|
public bool EnableScope(string name)
|
|
{
|
|
if (_scopes.TryGetValue(name, out Scope scope))
|
|
{
|
|
if (!scope.Enabled && ActivateScope(scope))
|
|
{
|
|
scope.SetEnabled(true);
|
|
SaveScopeFile(scope);
|
|
|
|
return true;
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
public bool DisableScope(string name)
|
|
{
|
|
if (_scopes.TryGetValue(name, out Scope scope))
|
|
{
|
|
if (scope.Enabled && DeactivateScope(scope))
|
|
{
|
|
scope.SetEnabled(false);
|
|
SaveScopeFile(scope);
|
|
|
|
return true;
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
public void SaveScope(string name)
|
|
{
|
|
if (_scopes.TryGetValue(name, out Scope scope))
|
|
SaveScopeFile(scope);
|
|
}
|
|
|
|
public IDictionary<string, string> GetAddressClientMap()
|
|
{
|
|
Dictionary<string, string> map = new Dictionary<string, string>();
|
|
|
|
foreach (KeyValuePair<string, Scope> scope in _scopes)
|
|
{
|
|
foreach (Lease lease in scope.Value.Leases)
|
|
{
|
|
if (!string.IsNullOrEmpty(lease.HostName))
|
|
map.Add(lease.Address.ToString(), lease.HostName);
|
|
}
|
|
}
|
|
|
|
return map;
|
|
}
|
|
|
|
#endregion
|
|
|
|
#region properties
|
|
|
|
public ICollection<Scope> Scopes
|
|
{ get { return _scopes.Values; } }
|
|
|
|
public Zone AuthoritativeZoneRoot
|
|
{
|
|
get { return _authoritativeZoneRoot; }
|
|
set { _authoritativeZoneRoot = value; }
|
|
}
|
|
|
|
public LogManager LogManager
|
|
{
|
|
get { return _log; }
|
|
set { _log = value; }
|
|
}
|
|
|
|
#endregion
|
|
}
|
|
}
|