From ad24146d9fa26629f7bbffbee0a4ab4aefb9038f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Damian=20B=C3=BCchel?= <damian.buechel@let.ethz.ch>
Date: Mon, 6 Apr 2020 14:13:13 +0200
Subject: [PATCH] SEBWIN-380: Implemented unit tests for browser resource
 handler.

---
 .../Handlers/ResourceHandlerTests.cs          | 179 ++++++++++++++++++
 .../SafeExamBrowser.Browser.UnitTests.csproj  |   1 +
 .../Handlers/ResourceHandler.cs               |  10 +-
 3 files changed, 185 insertions(+), 5 deletions(-)
 create mode 100644 SafeExamBrowser.Browser.UnitTests/Handlers/ResourceHandlerTests.cs

diff --git a/SafeExamBrowser.Browser.UnitTests/Handlers/ResourceHandlerTests.cs b/SafeExamBrowser.Browser.UnitTests/Handlers/ResourceHandlerTests.cs
new file mode 100644
index 00000000..abf1875e
--- /dev/null
+++ b/SafeExamBrowser.Browser.UnitTests/Handlers/ResourceHandlerTests.cs
@@ -0,0 +1,179 @@
+/*
+ * Copyright (c) 2020 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.Specialized;
+using System.Net.Mime;
+using CefSharp;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using Moq;
+using SafeExamBrowser.Browser.Contracts.Filters;
+using SafeExamBrowser.Configuration.Contracts;
+using SafeExamBrowser.I18n.Contracts;
+using SafeExamBrowser.Logging.Contracts;
+using SafeExamBrowser.Settings.Browser.Filter;
+using BrowserSettings = SafeExamBrowser.Settings.Browser.BrowserSettings;
+using Request = SafeExamBrowser.Browser.Contracts.Filters.Request;
+using ResourceHandler = SafeExamBrowser.Browser.Handlers.ResourceHandler;
+
+namespace SafeExamBrowser.Browser.UnitTests.Handlers
+{
+	[TestClass]
+	public class ResourceHandlerTests
+	{
+		private AppConfig appConfig;
+		private BrowserSettings settings;
+		private Mock<IRequestFilter> filter;
+		private Mock<ILogger> logger;
+		private Mock<IText> text;
+		private TestableResourceHandler sut;
+
+		[TestInitialize]
+		public void Initialize()
+		{
+			appConfig = new AppConfig();
+			settings = new BrowserSettings();
+			filter = new Mock<IRequestFilter>();
+			logger = new Mock<ILogger>();
+			text = new Mock<IText>();
+
+			sut = new TestableResourceHandler(appConfig, settings, filter.Object, logger.Object, text.Object);
+		}
+
+		[TestMethod]
+		public void MustAppendCustomHeaders()
+		{
+			var headers = default(NameValueCollection);
+			var request = new Mock<IRequest>();
+
+			request.SetupGet(r => r.Headers).Returns(new NameValueCollection());
+			request.SetupGet(r => r.Url).Returns("http://www.host.org");
+			request.SetupSet(r => r.Headers = It.IsAny<NameValueCollection>()).Callback<NameValueCollection>((h) => headers = h);
+			settings.SendConfigurationKey = true;
+			settings.SendExamKey = true;
+
+			var result = sut.OnBeforeResourceLoad(Mock.Of<IWebBrowser>(), Mock.Of<IBrowser>(), Mock.Of<IFrame>(), request.Object, Mock.Of<IRequestCallback>());
+
+			request.VerifyGet(r => r.Headers, Times.AtLeastOnce);
+			request.VerifySet(r => r.Headers = It.IsAny<NameValueCollection>(), Times.AtLeastOnce);
+
+			Assert.AreEqual(CefReturnValue.Continue, result);
+			Assert.IsNotNull(headers["X-SafeExamBrowser-ConfigKeyHash"]);
+			Assert.IsNotNull(headers["X-SafeExamBrowser-RequestHash"]);
+		}
+
+		[TestMethod]
+		public void MustBlockMailToUrls()
+		{
+			var request = new Mock<IRequest>();
+			var url = $"{Uri.UriSchemeMailto}:someone@somewhere.org";
+
+			request.SetupGet(r => r.Url).Returns(url);
+
+			var result = sut.OnBeforeResourceLoad(Mock.Of<IWebBrowser>(), Mock.Of<IBrowser>(), Mock.Of<IFrame>(), request.Object, Mock.Of<IRequestCallback>());
+
+			Assert.AreEqual(CefReturnValue.Cancel, result);
+		}
+
+		[TestMethod]
+		public void MustFilterContentRequests()
+		{
+			var request = new Mock<IRequest>();
+			var url = "www.test.org";
+
+			filter.Setup(f => f.Process(It.Is<Request>(r => r.Url.Equals(url)))).Returns(FilterResult.Block);
+			request.SetupGet(r => r.ResourceType).Returns(ResourceType.SubFrame);
+			request.SetupGet(r => r.Url).Returns(url);
+			settings.Filter.ProcessContentRequests = true;
+			settings.Filter.ProcessMainRequests = true;
+
+			var resourceHandler = sut.GetResourceHandler(Mock.Of<IWebBrowser>(), Mock.Of<IBrowser>(), Mock.Of<IFrame>(), request.Object);
+
+			filter.Verify(f => f.Process(It.Is<Request>(r => r.Url.Equals(url))), Times.Once);
+
+			Assert.IsNotNull(resourceHandler);
+		}
+
+		[TestMethod]
+		public void MustRedirectToDisablePdfToolbar()
+		{
+			var browser = new Mock<IWebBrowser>();
+			var headers = new NameValueCollection { { "Content-Type", MediaTypeNames.Application.Pdf } };
+			var request = new Mock<IRequest>();
+			var response = new Mock<IResponse>();
+			var url = "http://www.host.org/some-document";
+
+			request.SetupGet(r => r.ResourceType).Returns(ResourceType.MainFrame);
+			request.SetupGet(r => r.Url).Returns(url);
+			response.SetupGet(r => r.Headers).Returns(headers);
+			settings.AllowPdfReader = true;
+			settings.AllowPdfReaderToolbar = false;
+
+			var result = sut.OnResourceResponse(browser.Object, Mock.Of<IBrowser>(), Mock.Of<IFrame>(), request.Object, response.Object);
+
+			browser.Verify(b => b.Load(It.Is<string>(s => s.Equals($"{url}#toolbar=0"))), Times.Once);
+			Assert.IsTrue(result);
+
+			browser.Reset();
+			request.SetupGet(r => r.Url).Returns($"{url}#toolbar=0");
+
+			result = sut.OnResourceResponse(browser.Object, Mock.Of<IBrowser>(), Mock.Of<IFrame>(), request.Object, response.Object);
+
+			browser.Verify(b => b.Load(It.IsAny<string>()), Times.Never);
+			Assert.IsFalse(result);
+		}
+
+		[TestMethod]
+		public void MustReplaceSebScheme()
+		{
+			var request = new Mock<IRequest>();
+			var url = default(string);
+
+			appConfig.SebUriScheme = "abc";
+			appConfig.SebUriSchemeSecure = "abcs";
+			request.SetupGet(r => r.Headers).Returns(new NameValueCollection());
+			request.SetupGet(r => r.Url).Returns($"{appConfig.SebUriScheme}://www.host.org");
+			request.SetupSet(r => r.Url = It.IsAny<string>()).Callback<string>(u => url = u);
+
+			var result = sut.OnBeforeResourceLoad(Mock.Of<IWebBrowser>(), Mock.Of<IBrowser>(), Mock.Of<IFrame>(), request.Object, Mock.Of<IRequestCallback>());
+
+			Assert.AreEqual(CefReturnValue.Continue, result);
+			Assert.AreEqual("http://www.host.org/", url);
+
+			request.SetupGet(r => r.Url).Returns($"{appConfig.SebUriSchemeSecure}://www.host.org");
+			request.SetupSet(r => r.Url = It.IsAny<string>()).Callback<string>(u => url = u);
+
+			result = sut.OnBeforeResourceLoad(Mock.Of<IWebBrowser>(), Mock.Of<IBrowser>(), Mock.Of<IFrame>(), request.Object, Mock.Of<IRequestCallback>());
+
+			Assert.AreEqual(CefReturnValue.Continue, result);
+			Assert.AreEqual("https://www.host.org/", url);
+		}
+
+		private class TestableResourceHandler : ResourceHandler
+		{
+			internal TestableResourceHandler(AppConfig appConfig, BrowserSettings settings, IRequestFilter filter, ILogger logger, IText text) : base(appConfig, settings, filter, logger, text)
+			{
+			}
+
+			public new IResourceHandler GetResourceHandler(IWebBrowser webBrowser, IBrowser browser, IFrame frame, IRequest request)
+			{
+				return base.GetResourceHandler(webBrowser, browser, frame, request);
+			}
+
+			public new CefReturnValue OnBeforeResourceLoad(IWebBrowser webBrowser, IBrowser browser, IFrame frame, IRequest request, IRequestCallback callback)
+			{
+				return base.OnBeforeResourceLoad(webBrowser, browser, frame, request, callback);
+			}
+
+			public new bool OnResourceResponse(IWebBrowser webBrowser, IBrowser browser, IFrame frame, IRequest request, IResponse response)
+			{
+				return base.OnResourceResponse(webBrowser, browser, frame, request, response);
+			}
+		}
+	}
+}
diff --git a/SafeExamBrowser.Browser.UnitTests/SafeExamBrowser.Browser.UnitTests.csproj b/SafeExamBrowser.Browser.UnitTests/SafeExamBrowser.Browser.UnitTests.csproj
index 24e4554d..818fa547 100644
--- a/SafeExamBrowser.Browser.UnitTests/SafeExamBrowser.Browser.UnitTests.csproj
+++ b/SafeExamBrowser.Browser.UnitTests/SafeExamBrowser.Browser.UnitTests.csproj
@@ -97,6 +97,7 @@
     <Compile Include="Handlers\KeyboardHandlerTests.cs" />
     <Compile Include="Handlers\LifeSpanHandlerTests.cs" />
     <Compile Include="Handlers\RequestHandlerTests.cs" />
+    <Compile Include="Handlers\ResourceHandlerTests.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
   </ItemGroup>
   <ItemGroup>
diff --git a/SafeExamBrowser.Browser/Handlers/ResourceHandler.cs b/SafeExamBrowser.Browser/Handlers/ResourceHandler.cs
index a9a8bb7e..9019719e 100644
--- a/SafeExamBrowser.Browser/Handlers/ResourceHandler.cs
+++ b/SafeExamBrowser.Browser/Handlers/ResourceHandler.cs
@@ -47,14 +47,14 @@ namespace SafeExamBrowser.Browser.Handlers
 			this.text = text;
 		}
 
-		protected override IResourceHandler GetResourceHandler(IWebBrowser chromiumWebBrowser, IBrowser browser, IFrame frame, IRequest request)
+		protected override IResourceHandler GetResourceHandler(IWebBrowser webBrowser, IBrowser browser, IFrame frame, IRequest request)
 		{
 			if (Block(request))
 			{
 				return ResourceHandlerFor(request.ResourceType);
 			}
 
-			return base.GetResourceHandler(chromiumWebBrowser, browser, frame, request);
+			return base.GetResourceHandler(webBrowser, browser, frame, request);
 		}
 
 		protected override CefReturnValue OnBeforeResourceLoad(IWebBrowser webBrowser, IBrowser browser, IFrame frame, IRequest request, IRequestCallback callback)
@@ -70,16 +70,16 @@ namespace SafeExamBrowser.Browser.Handlers
 			return base.OnBeforeResourceLoad(webBrowser, browser, frame, request, callback);
 		}
 
-		protected override bool OnResourceResponse(IWebBrowser chromiumWebBrowser, IBrowser browser, IFrame frame, IRequest request, IResponse response)
+		protected override bool OnResourceResponse(IWebBrowser webBrowser, IBrowser browser, IFrame frame, IRequest request, IResponse response)
 		{
 			if (RedirectToDisablePdfToolbar(request, response, out var url))
 			{
-				chromiumWebBrowser.Load(url);
+				webBrowser.Load(url);
 
 				return true;
 			}
 
-			return base.OnResourceResponse(chromiumWebBrowser, browser, frame, request, response);
+			return base.OnResourceResponse(webBrowser, browser, frame, request, response);
 		}
 
 		private void AppendCustomHeaders(IRequest request)