Restore SEBPatch

SafeExamBrowser.Client/Communication/ClientHost.cs

@@ -0,0 +1,111 @@
+/*
+ * Copyright (c) 2024 ETH Zürich, IT Services
+ * 
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+using System;
+using SafeExamBrowser.Communication.Contracts;
+using SafeExamBrowser.Communication.Contracts.Data;
+using SafeExamBrowser.Communication.Contracts.Events;
+using SafeExamBrowser.Communication.Contracts.Hosts;
+using SafeExamBrowser.Communication.Hosts;
+using SafeExamBrowser.Logging.Contracts;
+
+namespace SafeExamBrowser.Client.Communication
+{
+	internal class ClientHost : BaseHost, IClientHost
+	{
+		private bool allowConnection;
+		private int processId;
+
+		public Guid AuthenticationToken { private get; set; }
+		public bool IsConnected { get; private set; }
+
+		public event CommunicationEventHandler<ExamSelectionRequestEventArgs> ExamSelectionRequested;
+		public event CommunicationEventHandler<MessageBoxRequestEventArgs> MessageBoxRequested;
+		public event CommunicationEventHandler<PasswordRequestEventArgs> PasswordRequested;
+		public event CommunicationEventHandler ReconfigurationAborted;
+		public event CommunicationEventHandler<ReconfigurationEventArgs> ReconfigurationDenied;
+		public event CommunicationEventHandler RuntimeDisconnected;
+		public event CommunicationEventHandler<ServerFailureActionRequestEventArgs> ServerFailureActionRequested;
+		public event CommunicationEventHandler Shutdown;
+
+		public ClientHost(
+			string address,
+			IHostObjectFactory factory,
+			ILogger logger,
+			int processId,
+			int timeout_ms) : base(address, factory, logger, timeout_ms)
+		{
+			this.allowConnection = true;
+			this.processId = processId;
+		}
+
+		protected override bool OnConnect(Guid? token)
+		{
+			var authenticated = AuthenticationToken == token;
+			var accepted = allowConnection && authenticated;
+
+			if (accepted)
+			{
+				allowConnection = false;
+				IsConnected = true;
+			}
+
+			return accepted;
+		}
+
+		protected override void OnDisconnect(Interlocutor interlocutor)
+		{
+			if (interlocutor == Interlocutor.Runtime)
+			{
+				RuntimeDisconnected?.Invoke();
+				IsConnected = false;
+			}
+		}
+
+		protected override Response OnReceive(Message message)
+		{
+			switch (message)
+			{
+				case ExamSelectionRequestMessage m:
+					ExamSelectionRequested?.InvokeAsync(new ExamSelectionRequestEventArgs { Exams = m.Exams, RequestId = m.RequestId });
+					return new SimpleResponse(SimpleResponsePurport.Acknowledged);
+				case MessageBoxRequestMessage m:
+					MessageBoxRequested?.InvokeAsync(new MessageBoxRequestEventArgs { Action = m.Action, Icon = m.Icon, Message = m.Message, RequestId = m.RequestId, Title = m.Title });
+					return new SimpleResponse(SimpleResponsePurport.Acknowledged);
+				case PasswordRequestMessage m:
+					PasswordRequested?.InvokeAsync(new PasswordRequestEventArgs { Purpose = m.Purpose, RequestId = m.RequestId });
+					return new SimpleResponse(SimpleResponsePurport.Acknowledged);
+				case ReconfigurationDeniedMessage m:
+					ReconfigurationDenied?.InvokeAsync(new ReconfigurationEventArgs { ConfigurationPath = m.FilePath });
+					return new SimpleResponse(SimpleResponsePurport.Acknowledged);
+				case ServerFailureActionRequestMessage m:
+					ServerFailureActionRequested?.InvokeAsync(new ServerFailureActionRequestEventArgs { Message = m.Message, RequestId = m.RequestId, ShowFallback = m.ShowFallback });
+					return new SimpleResponse(SimpleResponsePurport.Acknowledged);
+			}
+
+			return new SimpleResponse(SimpleResponsePurport.UnknownMessage);
+		}
+
+		protected override Response OnReceive(SimpleMessagePurport message)
+		{
+			switch (message)
+			{
+				case SimpleMessagePurport.Authenticate:
+					return new AuthenticationResponse { ProcessId = processId };
+				case SimpleMessagePurport.ReconfigurationAborted:
+					ReconfigurationAborted?.InvokeAsync();
+					return new SimpleResponse(SimpleResponsePurport.Acknowledged);
+				case SimpleMessagePurport.Shutdown:
+					Shutdown?.Invoke();
+					return new SimpleResponse(SimpleResponsePurport.Acknowledged);
+			}
+
+			return new SimpleResponse(SimpleResponsePurport.UnknownMessage);
+		}
+	}
+}