Archive the traffic of observed accounts

.gitignore

@@ -325,3 +325,6 @@ src/AdminPanel/wwwroot/content/js/app.js.map
 .opencode/
 # Keys which are generated when the server runs locally.
 data-protection-keys/
+
+# The archive of the network observation, when the server is started from the repository.
+captures/

src/Dapr/GameServer.Host/Program.cs

@@ -7,6 +7,7 @@
 using MUnique.OpenMU.Dapr.Common;
 using MUnique.OpenMU.DataModel.Configuration;
 using MUnique.OpenMU.GameLogic;
+using MUnique.OpenMU.GameServer;
 using MUnique.OpenMU.GameServer.Host;
 using MUnique.OpenMU.Interfaces;
 using MUnique.OpenMU.PlugIns;
@@ -43,6 +44,7 @@
     .AddPeristenceProvider()
     .AddPlugInManager(plugInConfigurations)
     .AddIpResolver(args)
+    .AddNetworkObservation()
     .AddHostedService<GameServerHostedServiceWrapper>()
     .PublishManageableServer<IGameServer>();
 

src/DataModel/Configuration/SystemConfiguration.cs

@@ -88,6 +88,62 @@ public partial class SystemConfiguration
         ResourceType = typeof(Resources))]
     public string? TimeZoneId { get; set; }
 
+    /// <summary>
+    /// Gets or sets the number of data packets which are kept in memory per connection which
+    /// is watched in the network analyzer page of the admin panel.
+    /// </summary>
+    [Display(
+        Order = 7,
+        Name = nameof(Resources.SystemConfiguration_NetworkAnalyzerLiveBufferSize_Name),
+        Description = nameof(Resources.SystemConfiguration_NetworkAnalyzerLiveBufferSize_Description),
+        GroupName = nameof(Resources.SystemConfiguration_NetworkAnalyzer_Name),
+        ResourceType = typeof(Resources))]
+    public int NetworkAnalyzerLiveBufferSize { get; set; } = 5000;
+
+    /// <summary>
+    /// Gets or sets the path in which the traffic of the observed accounts is archived.
+    /// </summary>
+    [Display(
+        Order = 8,
+        Name = nameof(Resources.SystemConfiguration_NetworkObservationArchivePath_Name),
+        Description = nameof(Resources.SystemConfiguration_NetworkObservationArchivePath_Description),
+        GroupName = nameof(Resources.SystemConfiguration_NetworkAnalyzer_Name),
+        ResourceType = typeof(Resources))]
+    public string? NetworkObservationArchivePath { get; set; } = "captures";
+
+    /// <summary>
+    /// Gets or sets the maximum size of one file of an archived session, in megabytes.
+    /// </summary>
+    [Display(
+        Order = 9,
+        Name = nameof(Resources.SystemConfiguration_NetworkObservationMaxSessionSizeMb_Name),
+        Description = nameof(Resources.SystemConfiguration_NetworkObservationMaxSessionSizeMb_Description),
+        GroupName = nameof(Resources.SystemConfiguration_NetworkAnalyzer_Name),
+        ResourceType = typeof(Resources))]
+    public int NetworkObservationMaxSessionSizeMb { get; set; } = 50;
+
+    /// <summary>
+    /// Gets or sets the maximum size of the whole observation archive, in megabytes.
+    /// </summary>
+    [Display(
+        Order = 10,
+        Name = nameof(Resources.SystemConfiguration_NetworkObservationMaxTotalSizeMb_Name),
+        Description = nameof(Resources.SystemConfiguration_NetworkObservationMaxTotalSizeMb_Description),
+        GroupName = nameof(Resources.SystemConfiguration_NetworkAnalyzer_Name),
+        ResourceType = typeof(Resources))]
+    public int NetworkObservationMaxTotalSizeMb { get; set; } = 1000;
+
+    /// <summary>
+    /// Gets or sets the number of days after which an archived session is removed.
+    /// </summary>
+    [Display(
+        Order = 11,
+        Name = nameof(Resources.SystemConfiguration_NetworkObservationRetentionDays_Name),
+        Description = nameof(Resources.SystemConfiguration_NetworkObservationRetentionDays_Description),
+        GroupName = nameof(Resources.SystemConfiguration_NetworkAnalyzer_Name),
+        ResourceType = typeof(Resources))]
+    public int NetworkObservationRetentionDays { get; set; } = 30;
+
     /// <inheritdoc />
     public override string ToString()
     {

src/DataModel/Entities/Account.cs

@@ -137,6 +137,13 @@ public class Account
     /// </summary>
     public bool IsBot { get; set; }
 
+    /// <summary>
+    /// Gets or sets a value indicating whether the network traffic of this account is
+    /// observed. The game server then archives the traffic of each of its sessions, so that
+    /// it can be analyzed later - for example when the account is suspected of cheating.
+    /// </summary>
+    public bool IsNetworkObservationActive { get; set; }
+
     /// <summary>
     /// Gets or sets the characters.
     /// </summary>

src/DataModel/Properties/Resources.resx

@@ -160,4 +160,37 @@ or behind a firewall) and you want to use it within your computer or private net
     <data name="SocketAbbreviation" xml:space="preserve">
       <value>S</value>
     </data>
+	<data name="SystemConfiguration_NetworkAnalyzer_Name" xml:space="preserve">
+		<value>Network Analyzer</value>
+	</data>
+	<data name="SystemConfiguration_NetworkAnalyzerLiveBufferSize_Name" xml:space="preserve">
+		<value>Live buffer size</value>
+	</data>
+	<data name="SystemConfiguration_NetworkAnalyzerLiveBufferSize_Description" xml:space="preserve">
+		<value>The number of data packets which are kept in memory per connection which is watched in the network analyzer page. When more packets arrive, the oldest ones are dropped.</value>
+	</data>
+	<data name="SystemConfiguration_NetworkObservationArchivePath_Name" xml:space="preserve">
+		<value>Observation archive path</value>
+	</data>
+	<data name="SystemConfiguration_NetworkObservationArchivePath_Description" xml:space="preserve">
+		<value>The path in which the traffic of the observed accounts is archived. A relative path is resolved against the directory of the application. It must not point into a folder which is served by the web server - an archived session contains the login packet of the player in plain text.</value>
+	</data>
+	<data name="SystemConfiguration_NetworkObservationMaxSessionSizeMb_Name" xml:space="preserve">
+		<value>Maximum session size (MB)</value>
+	</data>
+	<data name="SystemConfiguration_NetworkObservationMaxSessionSizeMb_Description" xml:space="preserve">
+		<value>The maximum size of one file of an archived session, in megabytes. A session which grows bigger is continued in another file.</value>
+	</data>
+	<data name="SystemConfiguration_NetworkObservationMaxTotalSizeMb_Name" xml:space="preserve">
+		<value>Maximum archive size (MB)</value>
+	</data>
+	<data name="SystemConfiguration_NetworkObservationMaxTotalSizeMb_Description" xml:space="preserve">
+		<value>The maximum size of the whole observation archive, in megabytes. When it's exceeded, the oldest sessions are removed. A value of 0 means that the size is unlimited.</value>
+	</data>
+	<data name="SystemConfiguration_NetworkObservationRetentionDays_Name" xml:space="preserve">
+		<value>Archive retention (days)</value>
+	</data>
+	<data name="SystemConfiguration_NetworkObservationRetentionDays_Description" xml:space="preserve">
+		<value>The number of days after which an archived session is removed. A value of 0 means that the sessions are kept forever.</value>
+	</data>
 </root>

src/GameLogic/Player.cs

@@ -122,6 +122,11 @@ public Player(IGameContext gameContext)
     /// </summary>
     public event AsyncEventHandler<Player>? PlayerEnteredWorld;
 
+    /// <summary>
+    /// Occurs when the player has been logged in, so that its <see cref="Account"/> is known.
+    /// </summary>
+    public event AsyncEventHandler<Player>? PlayerLoggedIn;
+
     /// <summary>
     /// Occurs when the player left the world with his selected character.
     /// </summary>
@@ -581,6 +586,18 @@ public IPetCommandManager? PetCommandManager
     /// </summary>
     protected virtual bool IsPlayerStoreOpeningAfterEnterSupported => true;
 
+    /// <summary>
+    /// Sets the account of the player after a successful login and notifies the subscribers
+    /// of <see cref="PlayerLoggedIn"/>.
+    /// </summary>
+    /// <param name="account">The account of the player.</param>
+    /// <returns>The async task.</returns>
+    public async ValueTask SetAccountAsync(Account account)
+    {
+        this.Account = account;
+        await this.PlayerLoggedIn.SafeInvokeAsync(this).ConfigureAwait(false);
+    }
+
     /// <summary>
     /// Sets the selected character.
     /// </summary>

src/GameLogic/PlayerActions/LoginAction.cs

@@ -200,7 +200,7 @@ private async ValueTask HandleAlreadyConnectedAsync(Player player, string userna
 
     private async ValueTask FinishLoginAsync(Player player, string username, Account account)
     {
-        player.Account = account;
+        await player.SetAccountAsync(account).ConfigureAwait(false);
         player.Logger.LogDebug("Login successful, username: [{Username}].", username);
 
         if (player.IsTemplatePlayer)

src/GameServer/GameServer.cs

@@ -20,6 +20,7 @@ namespace MUnique.OpenMU.GameServer;
 using MUnique.OpenMU.GameServer.RemoteView;
 using MUnique.OpenMU.Interfaces;
 using MUnique.OpenMU.Network.Analyzer;
+using MUnique.OpenMU.Network.Analyzer.Archive;
 using MUnique.OpenMU.Persistence;
 using MUnique.OpenMU.PlugIns;
 using Nito.AsyncEx;
@@ -35,6 +36,8 @@ public sealed class GameServer : IGameServer, IDisposable, IAsyncDisposable, IGa
 
     private readonly ICollection<IGameServerListener> _listeners = new List<IGameServerListener>();
 
+    private readonly NetworkObservationHandler? _observationHandler;
+
     private ServerState _serverState;
 
     /// <summary>
@@ -49,6 +52,8 @@ public sealed class GameServer : IGameServer, IDisposable, IAsyncDisposable, IGa
     /// <param name="loggerFactory">The logger factory.</param>
     /// <param name="plugInManager">The plug in manager.</param>
     /// <param name="changeMediator"> The change mediatior.</param>
+    /// <param name="packetArchive">The archive for the traffic of observed accounts. It's only
+    /// available when the network observation is configured.</param>
     public GameServer(
         GameServerDefinition gameServerDefinition,
         IGuildServer guildServer,
@@ -58,12 +63,16 @@ public GameServer(
         IFriendServer friendServer,
         ILoggerFactory loggerFactory,
         PlugInManager plugInManager,
-        IConfigurationChangeMediator changeMediator)
+        IConfigurationChangeMediator changeMediator,
+        IPacketArchive? packetArchive = null)
     {
         this.Id = gameServerDefinition.ServerID;
         this.Description = gameServerDefinition.Description;
         this.ConfigurationId = gameServerDefinition.GetId();
         this._logger = loggerFactory.CreateLogger<GameServer>();
+        this._observationHandler = packetArchive is null
+            ? null
+            : new NetworkObservationHandler(packetArchive, this.Id, this.Description, loggerFactory.CreateLogger<NetworkObservationHandler>());
         try
         {
             var gameConfiguration = gameServerDefinition.GameConfiguration ?? throw Error.NotInitializedProperty(gameServerDefinition, nameof(gameServerDefinition.GameConfiguration));
@@ -489,6 +498,7 @@ private async ValueTask RemovePlayerFromGuildAsync(Player player, bool unregiste
     private async ValueTask OnPlayerConnectedAsync(PlayerConnectedEventArgs e)
     {
         var player = e.ConntectedPlayer;
+        this._observationHandler?.Watch(player);
         await this._gameContext.AddPlayerAsync(player).ConfigureAwait(false);
         await player.InvokeViewPlugInAsync<IShowLoginWindowPlugIn>(p => p.ShowLoginWindowAsync()).ConfigureAwait(false);
         await player.PlayerState.TryAdvanceToAsync(PlayerState.LoginScreen).ConfigureAwait(false);