DnsServer/DnsServerWindowsService/DnsServiceWorker.cs

140 lines
4.2 KiB
C#

/*
Technitium DNS Server
Copyright (C) 2024 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;
using Microsoft.Extensions.Hosting;
using Microsoft.Win32;
using System;
using System.Reflection;
using System.Threading;
using System.Threading.Tasks;
using TechnitiumLibrary.Net.Firewall;
namespace DnsServerWindowsService
{
public sealed class DnsServiceWorker : BackgroundService
{
readonly DnsWebService _service;
public DnsServiceWorker()
{
string configFolder = null;
string[] args = Environment.GetCommandLineArgs();
if (args.Length == 2)
configFolder = args[1];
_service = new DnsWebService(configFolder, new Uri("https://go.technitium.com/?id=43"), new Uri("https://go.technitium.com/?id=44"));
}
public override async Task StartAsync(CancellationToken cancellationToken)
{
CheckFirewallEntries();
await _service.StartAsync();
}
public override async Task StopAsync(CancellationToken cancellationToken)
{
await _service.StopAsync();
}
public override void Dispose()
{
if (_service != null)
_service.Dispose();
}
protected override Task ExecuteAsync(CancellationToken stoppingToken)
{
return Task.CompletedTask;
}
private static void CheckFirewallEntries()
{
bool autoFirewallEntry = true;
try
{
#pragma warning disable CA1416 // Validate platform compatibility
using (RegistryKey key = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Technitium\DNS Server", false))
{
if (key is not null)
autoFirewallEntry = Convert.ToInt32(key.GetValue("AutoFirewallEntry", 1)) == 1;
}
#pragma warning restore CA1416 // Validate platform compatibility
}
catch
{ }
if (autoFirewallEntry)
{
string appPath = Assembly.GetEntryAssembly().Location;
if (appPath.EndsWith(".dll", StringComparison.OrdinalIgnoreCase))
appPath = appPath.Substring(0, appPath.Length - 4) + ".exe";
if (!WindowsFirewallEntryExists(appPath))
AddWindowsFirewallEntry(appPath);
}
}
private static bool WindowsFirewallEntryExists(string appPath)
{
try
{
return WindowsFirewall.RuleExistsVista("", appPath) == RuleStatus.Allowed;
}
catch
{
return false;
}
}
private static bool AddWindowsFirewallEntry(string appPath)
{
try
{
RuleStatus status = WindowsFirewall.RuleExistsVista("", appPath);
switch (status)
{
case RuleStatus.Blocked:
case RuleStatus.Disabled:
WindowsFirewall.RemoveRuleVista("", appPath);
break;
case RuleStatus.Allowed:
return true;
}
WindowsFirewall.AddRuleVista("Technitium DNS Server", "Allows incoming connection request to the DNS server.", FirewallAction.Allow, appPath, Protocol.ANY, null, null, null, null, InterfaceTypeFlags.All, true, Direction.Inbound, true);
return true;
}
catch
{
return false;
}
}
}
}