fix: Catch Cryptographic Error and throw appropriate error message

Code was throwing an uncaught expection on cert gen when the cert
can't be written to disk, which would bubble beyond exception handlers
and crash the application. Catch the exception and tell the user to
turn off SSL. Also provide forum info on about tab so users can
contact devs for support.

Fixes #372

Author: qdot

Buttplug.Apps.ServerGUI/ServerControl.xaml.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.ObjectModel;
 using System.Net;
 using System.Net.NetworkInformation;
@@ -46,8 +46,8 @@ public ServerControl(IButtplugServerFactory bpFactory)
             _connUrls = new ConnUrlList();
             _port = 12345;
 
-            // Usually, if we throw errors then connect, it's not actually an error.
-            // If we don't connect after a second of throwing an exception, pop the toaster, but not before then.
+            // Usually, if we throw errors then connect, it's not actually an error. If we don't
+            // connect after a second of throwing an exception, pop the toaster, but not before then.
             _toastTimer = new Timer
             {
                 Interval = 1000,
@@ -206,11 +206,14 @@ public void StartServer()
             }
             catch (SocketException e)
             {
-                _log.LogException(e, true, e.Message);
+                _currentExceptionMessage = e.Message;
+                _log.LogException(e, true, _currentExceptionMessage);
             }
             catch (CryptographicException e)
             {
-                _log.LogException(e, true, e.Message);
+                _currentExceptionMessage =
+                    "Cannot start server with SSL. Try turning off SSL. The server can still be used with ScriptPlayer, but not web applications. If you need SSL, contact Buttplug Developers for support (see About Tab).";
+                _log.LogException(e, true, _currentExceptionMessage);
             }
         }
 
@@ -291,8 +294,7 @@ private void ConnItemCopy_Click(object sender, RoutedEventArgs e)
                 }
                 catch (Exception ex)
                 {
-                    // We've seen weird instances of can't open clipboard
-                    // but it's pretty rare. Log it.
+                    // We've seen weird instances of can't open clipboard but it's pretty rare. Log it.
                     _log.LogException(ex);
                 }
             }

Buttplug.Components.Controls/ButtplugAboutControl.xaml

@@ -1,4 +1,4 @@
-<UserControl x:Class="Buttplug.Components.Controls.ButtplugAboutControl"
+<UserControl x:Class="Buttplug.Components.Controls.ButtplugAboutControl"
              xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
              xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
              xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
@@ -18,11 +18,12 @@
 			<TextBlock Grid.Row="0" HorizontalAlignment="Left" Margin="150,0,0,0" VerticalAlignment="Stretch" Height="auto" Width="auto">
                 <Span FontSize="19" FontWeight="Bold">Buttplug <Run Name="AboutVersionNumber">1.0.0.0-branch</Run> (C# Edition)</Span><LineBreak />
                 <Run Name="AboutGitVersion" Cursor="Hand">0123456789abcdef0123456789abcdef01234567</Run><LineBreak />
-                By <Hyperlink NavigateUri="https://metafetish.com" RequestNavigate="Hyperlink_RequestNavigate">Metafetish</Hyperlink><LineBreak />
+                By <Hyperlink NavigateUri="https://metafetish.com" RequestNavigate="Hyperlink_RequestNavigate">Nonpolynomial Labs, LLC</Hyperlink><LineBreak />
                 <LineBreak/>
                 Software updates at <Hyperlink NavigateUri="https://github.com/metafetish" RequestNavigate="Hyperlink_RequestNavigate">https://buttplug.io/</Hyperlink><LineBreak/>
                 Documentation at <Hyperlink NavigateUri="https://buttplug.io/docs" RequestNavigate="Hyperlink_RequestNavigate">https://buttplug.io/docs</Hyperlink><LineBreak/>
                 Source code at <Hyperlink NavigateUri="https://github.com/metafetish" RequestNavigate="Hyperlink_RequestNavigate">https://github.com/metafetish</Hyperlink><LineBreak/>
+                Forums and Support at <Hyperlink NavigateUri="https://metafetish.club" RequestNavigate="Hyperlink_RequestNavigate">https://metafetish.club</Hyperlink><LineBreak/>
                 License information <Hyperlink Click="LicenseHyperlink_Click" >here</Hyperlink><LineBreak/>
 			</TextBlock>
 

Buttplug.Components.WebsocketServer/CertUtils.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Security.Cryptography;
@@ -21,13 +21,14 @@ namespace Buttplug.Components.WebsocketServer
 {
     internal static class CertUtils
     {
+        /// <exception cref="CryptographicException">Sometimes thrown due to issues generating keys.</exception>
         public static X509Certificate2 GetCert(string app, string hostname = "localhost")
         {
             var appPath = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData), app);
             var caPfx = Path.Combine(appPath, "ca.pfx");
             var certPfx = Path.Combine(appPath, "cert.pfx");
 
-            // Patch release rework of cert handling: our websocket server doesn't acept a chain!
+            // Patch release rework of cert handling: our websocket server doesn't accept a chain!
             if (File.Exists(caPfx))
             {
                 File.Delete(caPfx);
@@ -58,7 +59,8 @@ public static X509Certificate2 GetCert(string app, string hostname = "localhost"
                 X509KeyStorageFlags.Exportable | X509KeyStorageFlags.PersistKeySet);
         }
 
-        // Note: Much of this code comes from https://stackoverflow.com/a/22247129
+        /// Note: Much of this code comes from https://stackoverflow.com/a/22247129
+        /// <exception cref="CryptographicException">Sometimes thrown due to issues generating keys.</exception>
         private static X509Certificate2 GenerateSelfSignedCertificate(string subject)
         {
             const int keyStrength = 2048;
@@ -134,14 +136,10 @@ private static X509Certificate2 GenerateSelfSignedCertificate(string subject)
             var rsa = RsaPrivateKeyStructure.GetInstance(seq);
             var rsaparams = new RsaPrivateCrtKeyParameters(
                 rsa.Modulus, rsa.PublicExponent, rsa.PrivateExponent, rsa.Prime1, rsa.Prime2, rsa.Exponent1, rsa.Exponent2, rsa.Coefficient);
-            try
-            {
-                x509.PrivateKey = ToDotNetKey(rsaparams); // x509.PrivateKey = DotNetUtilities.ToRSA(rsaparams);
-            }
-            catch (CryptographicException e)
-            {
-                throw new Exception($"Exception on cert generation!\nSubject {subject}\nHostname {Environment.MachineName}\nSequenceCount {seq.Count} (should be 9?)", e);
-            }
+
+            // This can throw CryptographicException in some cases. Catch above here and deal with it
+            // in the application level.
+            x509.PrivateKey = ToDotNetKey(rsaparams); // x509.PrivateKey = DotNetUtilities.ToRSA(rsaparams);
 
             return x509;
         }