Disallow address reuse for port bind tests

src/Tgstation.Server.Host/Components/InstanceManager.cs

@@ -5,8 +5,6 @@ using Microsoft.Extensions.Options;
 using System;
 using System.Collections.Generic;
 using System.Linq;
-using System.Net;
-using System.Net.Sockets;
 using System.Threading;
 using System.Threading.Tasks;
 using Tgstation.Server.Api.Models;
@@ -16,6 +14,7 @@ using Tgstation.Server.Host.Configuration;
 using Tgstation.Server.Host.Controllers;
 using Tgstation.Server.Host.Core;
 using Tgstation.Server.Host.Database;
+using Tgstation.Server.Host.Extensions;
 using Tgstation.Server.Host.IO;
 using Tgstation.Server.Host.Jobs;
 using Tgstation.Server.Host.Security;
@@ -482,8 +481,7 @@ namespace Tgstation.Server.Host.Components
 
 			// This runs before the real socket is opened, ensures we don't perform reattaches unless we're fairly certain the bind won't fail
 			// If it does fail, DD will be killed.
-			using var hostingSocket = new Socket(SocketType.Stream, ProtocolType.Tcp);
-			hostingSocket.Bind(new IPEndPoint(IPAddress.Any, serverPortProvider.HttpApiPort));
+			SocketExtensions.BindTest(serverPortProvider.HttpApiPort);
 		}
 
 		/// <inheritdoc />

src/Tgstation.Server.Host/Components/Session/SessionControllerFactory.cs

@@ -2,7 +2,6 @@
 using System;
 using System.Globalization;
 using System.Linq;
-using System.Net;
 using System.Net.Sockets;
 using System.Text;
 using System.Threading;
@@ -16,6 +15,7 @@ using Tgstation.Server.Host.Components.Deployment;
 using Tgstation.Server.Host.Components.Interop;
 using Tgstation.Server.Host.Components.Interop.Bridge;
 using Tgstation.Server.Host.Core;
+using Tgstation.Server.Host.Extensions;
 using Tgstation.Server.Host.IO;
 using Tgstation.Server.Host.Jobs;
 using Tgstation.Server.Host.Security;
@@ -118,11 +118,9 @@ namespace Tgstation.Server.Host.Components.Session
 		/// <param name="port">The port number to test.</param>
 		static void PortBindTest(ushort port)
 		{
-			using var socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
-
 			try
 			{
-				socket.Bind(new IPEndPoint(IPAddress.Any, port));
+				SocketExtensions.BindTest(port);
 			}
 			catch (SocketException ex)
 			{

src/Tgstation.Server.Host/Extensions/SocketExtensions.cs

@@ -0,0 +1,23 @@
+using System.Net;
+using System.Net.Sockets;
+
+namespace Tgstation.Server.Host.Extensions
+{
+	/// <summary>
+	/// Extension methods for the <see cref="Socket"/> <see langword="class"/>.
+	/// </summary>
+	static class SocketExtensions
+	{
+		/// <summary>
+		/// Attempt to exclusively bind to a given <paramref name="port"/>.
+		/// </summary>
+		/// <param name="port">The port number to bind to.</param>
+		public static void BindTest(ushort port)
+		{
+			using var socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
+			socket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ExclusiveAddressUse, true);
+			socket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, false);
+			socket.Bind(new IPEndPoint(IPAddress.Any, port));
+		}
+	}
+}

tests/Tgstation.Server.Tests/Instance/JobsRequiredTest.cs

@@ -36,7 +36,8 @@ namespace Tgstation.Server.Tests.Instance
 			}
 
 			if (expectFailure ^ job.ExceptionDetails != null)
-				Assert.Fail(job.ExceptionDetails ?? $"Expected job \"{job.Id}\" \"{job.Description}\" to fail but it didn't");
+				Assert.Fail(job.ExceptionDetails
+					?? $"Expected job \"{job.Id}\" \"{job.Description}\" to fail {(expectedCode.HasValue ? $"with ErrorCode \"{expectedCode.Value}\" " : String.Empty)}but it didn't");
 
 			if (expectedCode.HasValue)
 				Assert.AreEqual(expectedCode.Value, job.ErrorCode, job.ExceptionDetails);

tests/Tgstation.Server.Tests/Instance/WatchdogTest.cs

@@ -141,6 +141,8 @@ namespace Tgstation.Server.Tests.Instance
 			Job startJob;
 			using (var blockSocket = new Socket(SocketType.Stream, ProtocolType.Tcp))
 			{
+				blockSocket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ExclusiveAddressUse, true);
+				blockSocket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, false);
 				blockSocket.Bind(new IPEndPoint(IPAddress.Any, 1337));
 				startJob = await instanceClient.DreamDaemon.Start(cancellationToken).ConfigureAwait(false);
 

tests/Tgstation.Server.Tests/IntegrationTest.cs

@@ -200,6 +200,8 @@ namespace Tgstation.Server.Tests
 				// http bind test https://github.com/tgstation/tgstation-server/issues/1065
 				using (var blockingSocket = new Socket(SocketType.Stream, ProtocolType.Tcp))
 				{
+					blockingSocket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ExclusiveAddressUse, true);
+					blockingSocket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, false);
 					blockingSocket.Bind(new IPEndPoint(IPAddress.Any, server.Url.Port));
 					try
 					{