Merge branch 'main' into jmccannon/ac/pm-15420-managed-to-claimed

bitwarden-server.sln

@@ -127,6 +127,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Infrastructure.Dapper.Test"
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Events.IntegrationTest", "test\Events.IntegrationTest\Events.IntegrationTest.csproj", "{4F4C63A9-AEE2-48C4-AB86-A5BCD665E401}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Core.IntegrationTest", "test\Core.IntegrationTest\Core.IntegrationTest.csproj", "{3631BA42-6731-4118-A917-DAA43C5032B9}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -319,6 +321,10 @@ Global
 		{4F4C63A9-AEE2-48C4-AB86-A5BCD665E401}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{4F4C63A9-AEE2-48C4-AB86-A5BCD665E401}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{4F4C63A9-AEE2-48C4-AB86-A5BCD665E401}.Release|Any CPU.Build.0 = Release|Any CPU
+		{3631BA42-6731-4118-A917-DAA43C5032B9}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{3631BA42-6731-4118-A917-DAA43C5032B9}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{3631BA42-6731-4118-A917-DAA43C5032B9}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{3631BA42-6731-4118-A917-DAA43C5032B9}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -370,6 +376,7 @@ Global
 		{90D85D8F-5577-4570-A96E-5A2E185F0F6F} = {DD5BD056-4AAE-43EF-BBD2-0B569B8DA84F}
 		{4A725DB3-BE4F-4C23-9087-82D0610D67AF} = {DD5BD056-4AAE-43EF-BBD2-0B569B8DA84F}
 		{4F4C63A9-AEE2-48C4-AB86-A5BCD665E401} = {DD5BD056-4AAE-43EF-BBD2-0B569B8DA84F}
+		{3631BA42-6731-4118-A917-DAA43C5032B9} = {DD5BD056-4AAE-43EF-BBD2-0B569B8DA84F}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {E01CBF68-2E20-425F-9EDB-E0A6510CA92F}

src/Billing/Billing.csproj

@@ -2,7 +2,6 @@
 
   <PropertyGroup>
     <UserSecretsId>bitwarden-Billing</UserSecretsId>
-    <MvcRazorCompileOnPublish>false</MvcRazorCompileOnPublish>
   </PropertyGroup>
 
   <PropertyGroup Condition=" '$(RunConfiguration)' == 'Billing' " />

src/Billing/Startup.cs

@@ -87,8 +87,7 @@ public class Startup
         // TODO: no longer be required - see PM-1880
         services.AddScoped<IServiceAccountRepository, NoopServiceAccountRepository>();
 
-        // Mvc
+        services.AddControllers(config =>
-        services.AddMvc(config =>
         {
             config.Filters.Add(new LoggingExceptionHandlerFilterAttribute());
         });

src/Billing/Views/Home/Index.cshtml

@@ -1,6 +0,0 @@
-@{
-    ViewData["Title"] = "Index";
-}
-
-<h2>Index</h2>
-

src/Billing/Views/Login/Index.cshtml

@@ -1,21 +0,0 @@
-@model LoginModel
-@{
-    ViewData["Title"] = "Login";
-}
-
-<div class="row justify-content-md-center">
-    <div class="col-4">
-        <p>Please enter your email address below to log in.</p>
-        <form asp-action="" method="post">
-            <div asp-validation-summary="ModelOnly" class="text-danger"></div>
-            <div class="form-group">
-                <label asp-for="Email" class="sr-only">Email Address</label>
-                <input asp-for="Email" type="email" class="form-control" placeholder="ex. john@example.com"
-                       required autofocus>
-                <span asp-validation-for="Email" class="invalid-feedback"></span>
-                <small class="form-text text-body-secondary">We'll email you a secure login link.</small>
-            </div>
-            <button class="btn btn-primary btn-block" type="submit">Continue</button>
-        </form>
-    </div>
-</div>

src/Billing/Views/Shared/Error.cshtml

@@ -1,14 +0,0 @@
-@{
-    ViewData["Title"] = "Error";
-}
-
-<h1 class="text-danger">Error.</h1>
-<h2 class="text-danger">An error occurred while processing your request.</h2>
-
-<h3>Development Mode</h3>
-<p>
-    Swapping to <strong>Development</strong> environment will display more detailed information about the error that occurred.
-</p>
-<p>
-    <strong>Development environment should not be enabled in deployed applications</strong>, as it can result in sensitive information from exceptions being displayed to end users. For local debugging, development environment can be enabled by setting the <strong>ASPNETCORE_ENVIRONMENT</strong> environment variable to <strong>Development</strong>, and restarting the application.
-</p>

src/Billing/Views/Shared/_Layout.cshtml

@@ -1,41 +0,0 @@
-<!DOCTYPE html>
-<html>
-<head>
-    <meta charset="utf-8" />
-    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-    <title>@ViewData["Title"] | Bitwarden Billing Portal</title>
-
-    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css"
-          integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">
-    <link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet"
-          integrity="sha384-wvfXpqpZZVQGK6TAh5PVlGOfQNHSoD2xbE+QkPxCAFlNEevoEH3Sl0sibVcOQVnN" crossorigin="anonymous">
-    <link rel="stylesheet" href="~/styles/billing.css">
-</head>
-<body>
-    <nav class="navbar navbar-expand-md navbar-dark bg-dark mb-4">
-        <div class="container">
-            <a class="navbar-brand" href="#"><i class="fa fa-lg fa-fw fa-shield"></i> Billing</a>
-            <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarCollapse"
-                    aria-controls="navbarCollapse" aria-expanded="false" aria-label="Toggle navigation">
-                <span class="navbar-toggler-icon"></span>
-            </button>
-            <div class="collapse navbar-collapse" id="navbarCollapse">
-                <ul class="navbar-nav mr-auto">
-                    <li class="nav-item active">
-                        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
-                    </li>
-                    <li class="nav-item">
-                        <a class="nav-link" href="#">Link</a>
-                    </li>
-                </ul>
-            </div>
-        </div>
-    </nav>
-
-    <main role="main" class="container">
-        @RenderBody()
-    </main>
-
-    @RenderSection("Scripts", required: false)
-</body>
-</html>

src/Billing/Views/_ViewImports.cshtml

@@ -1,3 +0,0 @@
-@using Bit.Billing
-@using Bit.Billing.Models
-@addTagHelper *, Microsoft.AspNetCore.Mvc.TagHelpers

src/Billing/Views/_ViewStart.cshtml

@@ -1,3 +0,0 @@
-@{
-    Layout = "_Layout";
-}

src/Billing/wwwroot/styles/billing.css

@@ -1,6 +0,0 @@
-.custom-select.input-validation-error ~ .invalid-feedback,
-.custom-select.input-validation-error ~ .invalid-tooltip,
-.form-control.input-validation-error ~ .invalid-feedback,
-.form-control.input-validation-error ~ .invalid-tooltip {
-    display: block;
-}

src/Core/Services/Implementations/MailKitSmtpMailDeliveryService.cs

@@ -34,6 +34,9 @@ public class MailKitSmtpMailDeliveryService : IMailDeliveryService
     }
 
     public async Task SendEmailAsync(Models.Mail.MailMessage message)
+        => await SendEmailAsync(message, CancellationToken.None);
+
+    public async Task SendEmailAsync(Models.Mail.MailMessage message, CancellationToken cancellationToken)
     {
         var mimeMessage = new MimeMessage();
         mimeMessage.From.Add(new MailboxAddress(_globalSettings.SiteName, _replyEmail));
@@ -76,25 +79,37 @@ public class MailKitSmtpMailDeliveryService : IMailDeliveryService
             if (!_globalSettings.Mail.Smtp.StartTls && !_globalSettings.Mail.Smtp.Ssl &&
                 _globalSettings.Mail.Smtp.Port == 25)
             {
-                await client.ConnectAsync(_globalSettings.Mail.Smtp.Host, _globalSettings.Mail.Smtp.Port,
+                await client.ConnectAsync(
-                    MailKit.Security.SecureSocketOptions.None);
+                    _globalSettings.Mail.Smtp.Host,
+                    _globalSettings.Mail.Smtp.Port,
+                    MailKit.Security.SecureSocketOptions.None,
+                    cancellationToken
+                );
             }
             else
             {
                 var useSsl = _globalSettings.Mail.Smtp.Port == 587 && !_globalSettings.Mail.Smtp.SslOverride ?
                     false : _globalSettings.Mail.Smtp.Ssl;
-                await client.ConnectAsync(_globalSettings.Mail.Smtp.Host, _globalSettings.Mail.Smtp.Port, useSsl);
+                await client.ConnectAsync(
+                    _globalSettings.Mail.Smtp.Host,
+                    _globalSettings.Mail.Smtp.Port,
+                    useSsl,
+                    cancellationToken
+                );
             }
 
             if (CoreHelpers.SettingHasValue(_globalSettings.Mail.Smtp.Username) &&
                 CoreHelpers.SettingHasValue(_globalSettings.Mail.Smtp.Password))
             {
-                await client.AuthenticateAsync(_globalSettings.Mail.Smtp.Username,
+                await client.AuthenticateAsync(
-                    _globalSettings.Mail.Smtp.Password);
+                    _globalSettings.Mail.Smtp.Username,
+                    _globalSettings.Mail.Smtp.Password,
+                    cancellationToken
+                );
             }
 
-            await client.SendAsync(mimeMessage);
+            await client.SendAsync(mimeMessage, cancellationToken);
-            await client.DisconnectAsync(true);
+            await client.DisconnectAsync(true, cancellationToken);
         }
     }
 }

test/Core.IntegrationTest/Core.IntegrationTest.csproj

@@ -0,0 +1,29 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net8.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+
+    <IsPackable>false</IsPackable>
+    <IsTestProject>true</IsTestProject>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="coverlet.collector" Version="6.0.0" />
+    <PackageReference Include="MartinCostello.Logging.XUnit" Version="0.5.1" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.8.0" />
+    <PackageReference Include="Rnwood.SmtpServer" Version="3.1.0-ci0868" />
+    <PackageReference Include="xunit" Version="2.5.3" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="2.5.3" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <Using Include="Xunit" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\..\src\Core\Core.csproj" />
+  </ItemGroup>
+
+</Project>

test/Core.IntegrationTest/MailKitSmtpMailDeliveryServiceTests.cs

@@ -0,0 +1,410 @@
+using System.Security.Cryptography;
+using System.Security.Cryptography.X509Certificates;
+using Bit.Core.Models.Mail;
+using Bit.Core.Services;
+using Bit.Core.Settings;
+using MailKit.Security;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Logging.Abstractions;
+using Rnwood.SmtpServer;
+using Rnwood.SmtpServer.Extensions.Auth;
+using Xunit.Abstractions;
+
+namespace Bit.Core.IntegrationTest;
+
+public class MailKitSmtpMailDeliveryServiceTests
+{
+    private readonly X509Certificate2 _selfSignedCert;
+
+    public MailKitSmtpMailDeliveryServiceTests(ITestOutputHelper testOutputHelper)
+    {
+        ConfigureSmtpServerLogging(testOutputHelper);
+
+        _selfSignedCert = CreateSelfSignedCert("localhost");
+    }
+
+    private static X509Certificate2 CreateSelfSignedCert(string commonName)
+    {
+        using var rsa = RSA.Create(2048);
+        var certRequest = new CertificateRequest($"CN={commonName}", rsa, HashAlgorithmName.SHA256, RSASignaturePadding.Pkcs1);
+        return certRequest.CreateSelfSigned(DateTimeOffset.UtcNow, DateTimeOffset.UtcNow.AddYears(1));
+    }
+
+    private static async Task SaveCertAsync(string filePath, X509Certificate2 certificate)
+    {
+        await File.WriteAllBytesAsync(filePath, certificate.Export(X509ContentType.Cert));
+    }
+
+    private static void ConfigureSmtpServerLogging(ITestOutputHelper testOutputHelper)
+    {
+        // Unfortunately this package doesn't public expose its logging infrastructure
+        // so we use private reflection to try and access it. 
+        try
+        {
+            var loggingType = typeof(DefaultServerBehaviour).Assembly.GetType("Rnwood.SmtpServer.Logging")
+                ?? throw new Exception("No type found in RnWood.SmtpServer named 'Logging'");
+
+            var factoryProperty = loggingType.GetProperty("Factory")
+                ?? throw new Exception($"No property named 'Factory' found on class {loggingType.FullName}");
+
+            var factoryPropertyGet = factoryProperty.GetMethod
+                ?? throw new Exception($"{loggingType.FullName}.{factoryProperty.Name} does not have a get method.");
+
+            if (factoryPropertyGet.Invoke(null, null) is not ILoggerFactory loggerFactory)
+            {
+                throw new Exception($"{loggingType.FullName}.{factoryProperty.Name} is not of type 'ILoggerFactory'" +
+                    $"instead it's type '{factoryProperty.PropertyType.FullName}'");
+            }
+
+            loggerFactory.AddXUnit(testOutputHelper);
+        }
+        catch (Exception ex)
+        {
+            testOutputHelper.WriteLine($"Failed to configure logging for RnWood.SmtpServer (logging will not be configured):\n{ex.Message}");
+        }
+    }
+    private static int RandomPort()
+    {
+        return Random.Shared.Next(50000, 60000);
+    }
+
+    private static GlobalSettings GetSettings(Action<GlobalSettings> configure)
+    {
+        var globalSettings = new GlobalSettings();
+        globalSettings.SiteName = "TestSiteName";
+        globalSettings.Mail.ReplyToEmail = "test@example.com";
+        globalSettings.Mail.Smtp.Host = "localhost";
+        // Set common defaults
+        configure(globalSettings);
+        return globalSettings;
+    }
+
+    [Fact]
+    public async Task SendEmailAsync_SmtpServerUsingSelfSignedCert_CertNotInTrustedRootStore_ThrowsException()
+    {
+        // If an SMTP server is using a self signed cert we currently require
+        // that the certificate for their SMTP server is installed in the root CA
+        // we are building the ability to do so without installing it, when we add that
+        // this test can be copied, and changed to utilize that new feature and instead of
+        // failing it should successfully send the email.
+        var port = RandomPort();
+        var behavior = new DefaultServerBehaviour(false, port, _selfSignedCert);
+        using var smtpServer = new SmtpServer(behavior);
+        smtpServer.Start();
+
+        var globalSettings = GetSettings(gs =>
+        {
+            gs.Mail.Smtp.Port = port;
+            gs.Mail.Smtp.Ssl = true;
+        });
+
+        var mailKitDeliveryService = new MailKitSmtpMailDeliveryService(
+            globalSettings,
+            NullLogger<MailKitSmtpMailDeliveryService>.Instance
+        );
+
+        await Assert.ThrowsAsync<SslHandshakeException>(
+            async () => await mailKitDeliveryService.SendEmailAsync(new MailMessage
+            {
+                Subject = "Test",
+                ToEmails = ["test@example.com"],
+                TextContent = "Hi",
+            }, new CancellationTokenSource(TimeSpan.FromSeconds(5)).Token)
+        );
+    }
+
+    [Fact(Skip = "Upcoming feature")]
+    public async Task SendEmailAsync_SmtpServerUsingSelfSignedCert_CertInCustomLocation_Works()
+    {
+        // If an SMTP server is using a self signed cert we will in the future
+        // allow a custom location for certificates to be stored and the certitifactes 
+        // stored there will also be trusted.
+        var port = RandomPort();
+        var behavior = new DefaultServerBehaviour(false, port, _selfSignedCert);
+        using var smtpServer = new SmtpServer(behavior);
+        smtpServer.Start();
+
+        var globalSettings = GetSettings(gs =>
+        {
+            gs.Mail.Smtp.Port = port;
+            gs.Mail.Smtp.Ssl = true;
+        });
+
+        // TODO: Setup custom location and save self signed cert there.
+        // await SaveCertAsync("./my-location", _selfSignedCert);
+
+        var mailKitDeliveryService = new MailKitSmtpMailDeliveryService(
+            globalSettings,
+            NullLogger<MailKitSmtpMailDeliveryService>.Instance
+        );
+
+        var tcs = new TaskCompletionSource();
+        var cts = new CancellationTokenSource(TimeSpan.FromSeconds(5));
+        cts.Token.Register(() => _ = tcs.TrySetCanceled());
+
+        behavior.MessageReceivedEventHandler += (sender, args) =>
+        {
+            if (args.Message.Recipients.Contains("test1@example.com"))
+            {
+                tcs.SetResult();
+            }
+            return Task.CompletedTask;
+        };
+
+        await mailKitDeliveryService.SendEmailAsync(new MailMessage
+        {
+            Subject = "Test",
+            ToEmails = ["test1@example.com"],
+            TextContent = "Hi",
+        }, cts.Token);
+
+        // Wait for email
+        await tcs.Task;
+    }
+
+    [Fact(Skip = "Upcoming feature")]
+    public async Task SendEmailAsync_SmtpServerUsingSelfSignedCert_CertInCustomLocation_WithUnrelatedCerts_Works()
+    {
+        // If an SMTP server is using a self signed cert we will in the future
+        // allow a custom location for certificates to be stored and the certitifactes 
+        // stored there will also be trusted.
+        var port = RandomPort();
+        var behavior = new DefaultServerBehaviour(false, port, _selfSignedCert);
+        using var smtpServer = new SmtpServer(behavior);
+        smtpServer.Start();
+
+        var globalSettings = GetSettings(gs =>
+        {
+            gs.Mail.Smtp.Port = port;
+            gs.Mail.Smtp.Ssl = true;
+        });
+
+        // TODO: Setup custom location and save self signed cert there
+        // along with another self signed cert that is not related to 
+        // the SMTP server.
+        // await SaveCertAsync("./my-location", _selfSignedCert);
+        // await SaveCertAsync("./my-location", CreateSelfSignedCert("example.com"));
+
+        var mailKitDeliveryService = new MailKitSmtpMailDeliveryService(
+            globalSettings,
+            NullLogger<MailKitSmtpMailDeliveryService>.Instance
+        );
+
+        var tcs = new TaskCompletionSource();
+        var cts = new CancellationTokenSource(TimeSpan.FromSeconds(5));
+        cts.Token.Register(() => _ = tcs.TrySetCanceled());
+
+        behavior.MessageReceivedEventHandler += (sender, args) =>
+        {
+            if (args.Message.Recipients.Contains("test1@example.com"))
+            {
+                tcs.SetResult();
+            }
+            return Task.CompletedTask;
+        };
+
+        await mailKitDeliveryService.SendEmailAsync(new MailMessage
+        {
+            Subject = "Test",
+            ToEmails = ["test1@example.com"],
+            TextContent = "Hi",
+        }, cts.Token);
+
+        // Wait for email
+        await tcs.Task;
+    }
+
+    [Fact]
+    public async Task SendEmailAsync_Succeeds_WhenCertIsSelfSigned_ServerIsTrusted()
+    {
+        // When the setting `TrustServer = true` is set even if the cert is 
+        // self signed and the cert is not trusted in anyway the connection should
+        // still go through.
+        var port = RandomPort();
+        var behavior = new DefaultServerBehaviour(false, port, _selfSignedCert);
+        using var smtpServer = new SmtpServer(behavior);
+        smtpServer.Start();
+
+        var globalSettings = GetSettings(gs =>
+        {
+            gs.Mail.Smtp.Port = port;
+            gs.Mail.Smtp.Ssl = true;
+            gs.Mail.Smtp.TrustServer = true;
+        });
+
+        var mailKitDeliveryService = new MailKitSmtpMailDeliveryService(
+            globalSettings,
+            NullLogger<MailKitSmtpMailDeliveryService>.Instance
+        );
+
+        var tcs = new TaskCompletionSource();
+        var cts = new CancellationTokenSource(TimeSpan.FromSeconds(5));
+        cts.Token.Register(() => _ = tcs.TrySetCanceled());
+
+        behavior.MessageReceivedEventHandler += (sender, args) =>
+        {
+            if (args.Message.Recipients.Contains("test1@example.com"))
+            {
+                tcs.SetResult();
+            }
+            return Task.CompletedTask;
+        };
+
+        await mailKitDeliveryService.SendEmailAsync(new MailMessage
+        {
+            Subject = "Test",
+            ToEmails = ["test1@example.com"],
+            TextContent = "Hi",
+        }, cts.Token);
+
+        // Wait for email
+        await tcs.Task;
+    }
+
+    [Fact]
+    public async Task SendEmailAsync_FailsConnectingWithTls_ServerDoesNotSupportTls()
+    {
+        // If the SMTP server is not setup to use TLS but our server is expecting it
+        // to, we should fail.
+        var port = RandomPort();
+        var behavior = new DefaultServerBehaviour(false, port);
+        using var smtpServer = new SmtpServer(behavior);
+        smtpServer.Start();
+
+        var globalSettings = GetSettings(gs =>
+        {
+            gs.Mail.Smtp.Port = port;
+            gs.Mail.Smtp.Ssl = true;
+            gs.Mail.Smtp.TrustServer = true;
+        });
+
+        var mailKitDeliveryService = new MailKitSmtpMailDeliveryService(
+            globalSettings,
+            NullLogger<MailKitSmtpMailDeliveryService>.Instance
+        );
+
+        var cts = new CancellationTokenSource(TimeSpan.FromSeconds(5));
+
+        await Assert.ThrowsAsync<SslHandshakeException>(
+            async () => await mailKitDeliveryService.SendEmailAsync(new MailMessage
+            {
+                Subject = "Test",
+                ToEmails = ["test1@example.com"],
+                TextContent = "Hi",
+            }, cts.Token)
+        );
+    }
+
+    [Fact(Skip = "Requires permission to privileged port")]
+    public async Task SendEmailAsync_Works_NoSsl()
+    {
+        // If the SMTP server isn't set up with any SSL/TLS and we dont' expect
+        // any, then the email should go through just fine. Just without encryption.
+        // This test has to use port 25
+        var port = 25;
+        var behavior = new DefaultServerBehaviour(false, port);
+        using var smtpServer = new SmtpServer(behavior);
+        smtpServer.Start();
+
+        var globalSettings = GetSettings(gs =>
+        {
+            gs.Mail.Smtp.Port = port;
+            gs.Mail.Smtp.Ssl = false;
+            gs.Mail.Smtp.StartTls = false;
+        });
+
+        var mailKitDeliveryService = new MailKitSmtpMailDeliveryService(
+            globalSettings,
+            NullLogger<MailKitSmtpMailDeliveryService>.Instance
+        );
+
+        var tcs = new TaskCompletionSource();
+        var cts = new CancellationTokenSource(TimeSpan.FromSeconds(5));
+        cts.Token.Register(() => _ = tcs.TrySetCanceled());
+
+        behavior.MessageReceivedEventHandler += (sender, args) =>
+        {
+            if (args.Message.Recipients.Contains("test1@example.com"))
+            {
+                tcs.SetResult();
+            }
+            return Task.CompletedTask;
+        };
+
+        await mailKitDeliveryService.SendEmailAsync(new MailMessage
+        {
+            Subject = "Test",
+            ToEmails = ["test1@example.com"],
+            TextContent = "Hi",
+        }, cts.Token);
+
+        // Wait for email
+        await tcs.Task;
+    }
+
+    [Fact]
+    public async Task SendEmailAsync_Succeeds_WhenServerNeedsToAuthenticate()
+    {
+        // When the setting `TrustServer = true` is set even if the cert is 
+        // self signed and the cert is not trusted in anyway the connection should
+        // still go through.
+        var port = RandomPort();
+        var behavior = new DefaultServerBehaviour(false, port, _selfSignedCert);
+        behavior.AuthenticationCredentialsValidationRequiredEventHandler += (sender, args) =>
+        {
+            args.AuthenticationResult = AuthenticationResult.Failure;
+            if (args.Credentials is not UsernameAndPasswordAuthenticationCredentials usernameAndPasswordCreds)
+            {
+                return Task.CompletedTask;
+            }
+
+            if (usernameAndPasswordCreds.Username != "test" || usernameAndPasswordCreds.Password != "password")
+            {
+                return Task.CompletedTask;
+            }
+
+            args.AuthenticationResult = AuthenticationResult.Success;
+            return Task.CompletedTask;
+        };
+        using var smtpServer = new SmtpServer(behavior);
+        smtpServer.Start();
+
+        var globalSettings = GetSettings(gs =>
+        {
+            gs.Mail.Smtp.Port = port;
+            gs.Mail.Smtp.Ssl = true;
+            gs.Mail.Smtp.TrustServer = true;
+
+            gs.Mail.Smtp.Username = "test";
+            gs.Mail.Smtp.Password = "password";
+        });
+
+        var mailKitDeliveryService = new MailKitSmtpMailDeliveryService(
+            globalSettings,
+            NullLogger<MailKitSmtpMailDeliveryService>.Instance
+        );
+
+        var tcs = new TaskCompletionSource();
+        var cts = new CancellationTokenSource(TimeSpan.FromSeconds(5));
+        cts.Token.Register(() => _ = tcs.TrySetCanceled());
+
+        behavior.MessageReceivedEventHandler += (sender, args) =>
+        {
+            if (args.Message.Recipients.Contains("test1@example.com"))
+            {
+                tcs.SetResult();
+            }
+            return Task.CompletedTask;
+        };
+
+        await mailKitDeliveryService.SendEmailAsync(new MailMessage
+        {
+            Subject = "Test",
+            ToEmails = ["test1@example.com"],
+            TextContent = "Hi",
+        }, cts.Token);
+
+        // Wait for email
+        await tcs.Task;
+    }
+}