Restore SEBPatch

SafeExamBrowser.Runtime/Communication/RuntimeHost.cs

@@ -0,0 +1,109 @@
+/*
+ * 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.Runtime.Communication
+{
+	internal class RuntimeHost : BaseHost, IRuntimeHost
+	{
+		public bool AllowConnection { get; set; }
+		public Guid? AuthenticationToken { private get; set; }
+
+		public event CommunicationEventHandler ClientDisconnected;
+		public event CommunicationEventHandler ClientReady;
+		public event CommunicationEventHandler<ClientConfigurationEventArgs> ClientConfigurationNeeded;
+		public event CommunicationEventHandler<ExamSelectionReplyEventArgs> ExamSelectionReceived;
+		public event CommunicationEventHandler<MessageBoxReplyEventArgs> MessageBoxReplyReceived;
+		public event CommunicationEventHandler<PasswordReplyEventArgs> PasswordReceived;
+		public event CommunicationEventHandler<ReconfigurationEventArgs> ReconfigurationRequested;
+		public event CommunicationEventHandler<ServerFailureActionReplyEventArgs> ServerFailureActionReceived;
+		public event CommunicationEventHandler ShutdownRequested;
+
+		public RuntimeHost(string address, IHostObjectFactory factory, ILogger logger, int timeout_ms) : base(address, factory, logger, timeout_ms)
+		{
+		}
+
+		protected override bool OnConnect(Guid? token = null)
+		{
+			var authenticated = AuthenticationToken.HasValue && AuthenticationToken == token;
+			var accepted = AllowConnection && authenticated;
+
+			if (accepted)
+			{
+				AllowConnection = false;
+			}
+
+			return accepted;
+		}
+
+		protected override void OnDisconnect(Interlocutor interlocutor)
+		{
+			if (interlocutor == Interlocutor.Client)
+			{
+				ClientDisconnected?.Invoke();
+			}
+		}
+
+		protected override Response OnReceive(Message message)
+		{
+			switch (message)
+			{
+				case ExamSelectionReplyMessage m:
+					ExamSelectionReceived?.InvokeAsync(new ExamSelectionReplyEventArgs { RequestId = m.RequestId, SelectedExamId = m.SelectedExamId, Success = m.Success });
+					return new SimpleResponse(SimpleResponsePurport.Acknowledged);
+				case MessageBoxReplyMessage m:
+					MessageBoxReplyReceived?.InvokeAsync(new MessageBoxReplyEventArgs { RequestId = m.RequestId, Result = m.Result });
+					return new SimpleResponse(SimpleResponsePurport.Acknowledged);
+				case PasswordReplyMessage m:
+					PasswordReceived?.InvokeAsync(new PasswordReplyEventArgs { Password = m.Password, RequestId = m.RequestId, Success = m.Success });
+					return new SimpleResponse(SimpleResponsePurport.Acknowledged);
+				case ReconfigurationMessage m:
+					ReconfigurationRequested?.InvokeAsync(new ReconfigurationEventArgs { ConfigurationPath = m.ConfigurationPath, ResourceUrl = m.ResourceUrl });
+					return new SimpleResponse(SimpleResponsePurport.Acknowledged);
+				case ServerFailureActionReplyMessage m:
+					ServerFailureActionReceived?.InvokeAsync(new ServerFailureActionReplyEventArgs { Abort = m.Abort, Fallback = m.Fallback, RequestId = m.RequestId, Retry = m.Retry });
+					return new SimpleResponse(SimpleResponsePurport.Acknowledged);
+			}
+
+			return new SimpleResponse(SimpleResponsePurport.UnknownMessage);
+		}
+
+		protected override Response OnReceive(SimpleMessagePurport message)
+		{
+			switch (message)
+			{
+				case SimpleMessagePurport.ClientIsReady:
+					ClientReady?.Invoke();
+					return new SimpleResponse(SimpleResponsePurport.Acknowledged);
+				case SimpleMessagePurport.ConfigurationNeeded:
+					return HandleConfigurationRequest();
+				case SimpleMessagePurport.RequestShutdown:
+					ShutdownRequested?.Invoke();
+					return new SimpleResponse(SimpleResponsePurport.Acknowledged);
+			}
+
+			return new SimpleResponse(SimpleResponsePurport.UnknownMessage);
+		}
+
+		private Response HandleConfigurationRequest()
+		{
+			var args = new ClientConfigurationEventArgs();
+
+			ClientConfigurationNeeded?.Invoke(args);
+
+			return new ConfigurationResponse { Configuration = args.ClientConfiguration };
+		}
+	}
+}