SEBWIN-314: Started with network filter implementation.

SafeExamBrowser.Configuration/ConfigurationData/DataMapper.Network.cs

@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) 2019 ETH Zürich, Educational Development and Technology (LET)
+ * 
+ * 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.Collections.Generic;
+using SafeExamBrowser.Contracts.Configuration.Settings;
+using SafeExamBrowser.Contracts.Network.Filter;
+
+namespace SafeExamBrowser.Configuration.ConfigurationData
+{
+	internal partial class DataMapper
+	{
+		private void MapEnableContentRequestFilter(Settings settings, object value)
+		{
+			if (value is bool enable)
+			{
+				settings.Network.EnableContentRequestFilter = enable;
+			}
+		}
+
+		private void MapEnableMainRequestFilter(Settings settings, object value)
+		{
+			if (value is bool enable)
+			{
+				settings.Network.EnableMainRequestFilter = enable;
+			}
+		}
+
+		private void MapUrlFilterRules(Settings settings, object value)
+		{
+			const int ALLOW = 1;
+
+			if (value is IEnumerable<IDictionary<string, object>> ruleDataList)
+			{
+				foreach (var ruleData in ruleDataList)
+				{
+					if (ruleData.TryGetValue(Keys.Network.Filter.RuleIsActive, out var v) && v is bool active && active)
+					{
+						var rule = new FilterRule();
+
+						if (ruleData.TryGetValue(Keys.Network.Filter.RuleExpression, out v) && v is string expression)
+						{
+							rule.Expression = expression;
+						}
+
+						if (ruleData.TryGetValue(Keys.Network.Filter.RuleAction, out v) && v is int action)
+						{
+							rule.Result = action == ALLOW ? FilterResult.Allow : FilterResult.Block ;
+						}
+
+						if (ruleData.TryGetValue(Keys.Network.Filter.RuleExpressionIsRegex, out v) && v is bool regex)
+						{
+							rule.Type = regex ? FilterType.Regex : FilterType.Simplified;
+						}
+
+						settings.Network.FilterRules.Add(rule);
+					}
+				}
+			}
+		}
+	}
+}

SafeExamBrowser.Configuration/ConfigurationData/DataMapper.cs

@@ -22,6 +22,7 @@ namespace SafeExamBrowser.Configuration.ConfigurationData
 				MapConfigurationFileSettings(item.Key, item.Value, settings);
 				MapGeneralSettings(item.Key, item.Value, settings);
 				MapInputSettings(item.Key, item.Value, settings);
+				MapNetworkSettings(item.Key, item.Value, settings);
 				MapSecuritySettings(item.Key, item.Value, settings);
 				MapUserInterfaceSettings(item.Key, item.Value, settings);
 			}
@@ -192,6 +193,22 @@ namespace SafeExamBrowser.Configuration.ConfigurationData
 			}
 		}
 
+		private void MapNetworkSettings(string key, object value, Settings settings)
+		{
+			switch (key)
+			{
+				case Keys.Network.Filter.EnableContentRequestFilter:
+					MapEnableContentRequestFilter(settings, value);
+					break;
+				case Keys.Network.Filter.EnableMainRequestFilter:
+					MapEnableMainRequestFilter(settings, value);
+					break;
+				case Keys.Network.Filter.UrlFilterRules:
+					MapUrlFilterRules(settings, value);
+					break;
+			}
+		}
+
 		private void MapSecuritySettings(string key, object value, Settings settings)
 		{
 			switch (key)

SafeExamBrowser.Configuration/ConfigurationData/Keys.cs

@@ -113,6 +113,17 @@ namespace SafeExamBrowser.Configuration.ConfigurationData
 				internal const string CertificateType = "type";
 				internal const string EmbeddedCertificates = "embeddedCertificates";
 			}
+
+			internal static class Filter
+			{
+				internal const string EnableContentRequestFilter = "URLFilterEnableContentFilter";
+				internal const string EnableMainRequestFilter = "URLFilterEnable";
+				internal const string RuleAction = "action";
+				internal const string RuleIsActive = "active";
+				internal const string RuleExpression = "expression";
+				internal const string RuleExpressionIsRegex = "regex";
+				internal const string UrlFilterRules = "URLFilterRules";
+			}
 		}
 
 		internal static class Registry

SafeExamBrowser.Configuration/SafeExamBrowser.Configuration.csproj

@@ -81,6 +81,9 @@
     <Compile Include="ConfigurationData\DataMapper.Input.cs">
       <DependentUpon>DataMapper.cs</DependentUpon>
     </Compile>
+    <Compile Include="ConfigurationData\DataMapper.Network.cs">
+      <DependentUpon>DataMapper.cs</DependentUpon>
+    </Compile>
     <Compile Include="ConfigurationData\DataMapper.UserInterface.cs">
       <DependentUpon>DataMapper.cs</DependentUpon>
     </Compile>

SafeExamBrowser.Contracts/Configuration/Settings/NetworkSettings.cs

@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2019 ETH Zürich, Educational Development and Technology (LET)
+ * 
+ * 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 System.Collections.Generic;
+using SafeExamBrowser.Contracts.Network.Filter;
+
+namespace SafeExamBrowser.Contracts.Configuration.Settings
+{
+	/// <summary>
+	/// Defines all configuration options for network functionality.
+	/// </summary>
+	[Serializable]
+	public class NetworkSettings
+	{
+		/// <summary>
+		/// Defines whether all content requests for a web page should be filtered according to the defined <see cref="FilterRules"/>.
+		/// </summary>
+		public bool EnableContentRequestFilter { get; set; }
+
+		/// <summary>
+		/// Defines whether the main request for a web page should be filtered according to the defined <see cref="FilterRules"/>.
+		/// </summary>
+		public bool EnableMainRequestFilter { get; set; }
+
+		/// <summary>
+		/// Defines all rules to be used to filter network requests.
+		/// </summary>
+		public IList<FilterRule> FilterRules { get; set; }
+
+		public NetworkSettings()
+		{
+			FilterRules = new List<FilterRule>();
+		}
+	}
+}

SafeExamBrowser.Contracts/Configuration/Settings/Settings.cs

@@ -67,6 +67,11 @@ namespace SafeExamBrowser.Contracts.Configuration.Settings
 		/// </summary>
 		public MouseSettings Mouse { get; set; }
 
+		/// <summary>
+		/// All network-related settings.
+		/// </summary>
+		public NetworkSettings Network { get; set; }
+
 		/// <summary>
 		/// The hash code of the quit password.
 		/// </summary>
@@ -94,6 +99,7 @@ namespace SafeExamBrowser.Contracts.Configuration.Settings
 			Browser = new BrowserSettings();
 			Keyboard = new KeyboardSettings();
 			Mouse = new MouseSettings();
+			Network = new NetworkSettings();
 			Service = new ServiceSettings();
 			Taskbar = new TaskbarSettings();
 		}

SafeExamBrowser.Contracts/Network/Filter/FilterResult.cs

@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2019 ETH Zürich, Educational Development and Technology (LET)
+ * 
+ * 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/.
+ */
+
+namespace SafeExamBrowser.Contracts.Network.Filter
+{
+	/// <summary>
+	/// Defines all possible results of a request filter operation.
+	/// </summary>
+	public enum FilterResult
+	{
+		/// <summary>
+		/// Indicates that a request should be allowed.
+		/// </summary>
+		Allow,
+
+		/// <summary>
+		/// Indicates that a request should be blocked.
+		/// </summary>
+		Block
+	}
+}

SafeExamBrowser.Contracts/Network/Filter/FilterRule.cs

@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2019 ETH Zürich, Educational Development and Technology (LET)
+ * 
+ * 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;
+
+namespace SafeExamBrowser.Contracts.Network.Filter
+{
+	/// <summary>
+	/// Defines a network filter rule.
+	/// </summary>
+	[Serializable]
+	public class FilterRule
+	{
+		/// <summary>
+		/// The expression according to which requests should be filtered.
+		/// </summary>
+		public string Expression { get; set; }
+
+		/// <summary>
+		/// The filter result to be used when the <see cref="Expression"/> matches.
+		/// </summary>
+		public FilterResult Result { get; set; }
+
+		/// <summary>
+		/// The filter type which defines how the <see cref="Expression"/> is processed.
+		/// </summary>
+		public FilterType Type { get; set; }
+	}
+}

SafeExamBrowser.Contracts/Network/Filter/FilterType.cs

@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2019 ETH Zürich, Educational Development and Technology (LET)
+ * 
+ * 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/.
+ */
+
+namespace SafeExamBrowser.Contracts.Network.Filter
+{
+	/// <summary>
+	/// Defines all possible request filter types.
+	/// </summary>
+	public enum FilterType
+	{
+		/// <summary>
+		/// The filter is based on a regular expression.
+		/// </summary>
+		Regex,
+
+		/// <summary>
+		/// The filter is based on a simplified expression with wildcards.
+		/// </summary>
+		Simplified
+	}
+}

SafeExamBrowser.Contracts/Network/Filter/IRequestFilter.cs

@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2019 ETH Zürich, Educational Development and Technology (LET)
+ * 
+ * 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/.
+ */
+
+namespace SafeExamBrowser.Contracts.Network.Filter
+{
+	/// <summary>
+	/// Defines a filter to process network requests.
+	/// </summary>
+	public interface IRequestFilter
+	{
+		/// <summary>
+		/// Defines the default result to be returned by <see cref="Process(Request)"/> if no filter rule matches.
+		/// </summary>
+		FilterResult Default { set; }
+
+		/// <summary>
+		/// Loads the given <see cref="FilterRule"/> to be used when processing a request.
+		/// </summary>
+		void Load(FilterRule rule);
+
+		/// <summary>
+		/// Filters the given request according to the loaded <see cref="FilterRule"/>.
+		/// </summary>
+		FilterResult Process(Request request);
+	}
+}

SafeExamBrowser.Contracts/Network/Request.cs

@@ -0,0 +1,23 @@
+/*
+ * Copyright (c) 2019 ETH Zürich, Educational Development and Technology (LET)
+ * 
+ * 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;
+
+namespace SafeExamBrowser.Contracts.Network
+{
+	/// <summary>
+	/// Defines a network request.
+	/// </summary>
+	public class Request
+	{
+		/// <summary>
+		/// The uri of the request.
+		/// </summary>
+		public Uri Uri { get; set; }
+	}
+}

SafeExamBrowser.Contracts/SafeExamBrowser.Contracts.csproj

@@ -86,6 +86,8 @@
     <Compile Include="Configuration\Settings\ActionCenterSettings.cs" />
     <Compile Include="Configuration\Settings\AudioSettings.cs" />
     <Compile Include="Configuration\Settings\BrowserWindowSettings.cs" />
+    <Compile Include="Network\Filter\FilterRule.cs" />
+    <Compile Include="Configuration\Settings\NetworkSettings.cs" />
     <Compile Include="Configuration\Settings\ServiceSettings.cs" />
     <Compile Include="Configuration\Settings\UserInterfaceMode.cs" />
     <Compile Include="Applications\Events\IconChangedEventHandler.cs" />
@@ -100,6 +102,10 @@
     <Compile Include="Lockdown\IFeatureConfigurationFactory.cs" />
     <Compile Include="Lockdown\IFeatureConfigurationMonitor.cs" />
     <Compile Include="Lockdown\ISystemConfigurationUpdate.cs" />
+    <Compile Include="Network\Filter\FilterType.cs" />
+    <Compile Include="Network\Filter\IRequestFilter.cs" />
+    <Compile Include="Network\Filter\FilterResult.cs" />
+    <Compile Include="Network\Request.cs" />
     <Compile Include="Runtime\IRuntimeController.cs" />
     <Compile Include="Core\OperationModel\Events\ActionRequiredEventArgs.cs" />
     <Compile Include="Core\OperationModel\Events\ActionRequiredEventHandler.cs" />