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Configure fixed listening port on RDP api

I wrote a windows desktop sharing app using Microsoft RDP COM API.
activeSession = new RDPSession();
/* I can only have 1 attendee per-session */
activeSession.Invitations.CreateInvitation(authstr, groupname, password, 1);
but I need to start an RDP session at a given port (due to firewall policies) every time I generate an invitation to a session, instead of a random one.
Does anyone know a way to do that with that API? Any help is appreciated.

I found a way digging up a little bit MSDN documentation.
activeSession.Properties["PortId"] = listeningPort;
activeSession.Open();

Xamarin Android - VpnService is blocking all apps

An app I'm designing uses the VpnService, along with the VpnService.Builder, classes to generate a VPN in order to block traffic from specific apps. According to the documentation over at developer.android.com, all apps should be allowed through the VPN until Builder.AddAllowedApplication or Builder.AddDisallowedApplication is called.
When my VPN service starts up, for some reason, all apps are being disallowed which is strange. As soon as I disconnect from the VPN, all apps become available again. I need to to allow all, unless otherwise specified (which is what the documentation says should be happening). I start the VPN by calling the following:
private string _sTag = typeof(VpnService).Name;
private VpnServiceBinder _objBinder;
private ParcelFileDescriptor _objVpnInterface = null;
private PendingIntent _objPendingIntent = null;
...
if (_objVpnInterface == null)
{
Builder objVpnBuilder = new Builder(this);
objVpnBuilder.AddAddress("10.0.0.2", 32);
objVpnBuilder.AddRoute("0.0.0.0", 0);
// Form the interface
_objVpnInterface = objVpnBuilder.SetSession("Squelch").SetConfigureIntent(_objPendingIntent).Establish();
// Disallow instagram as a test
objVpnBuilder.AddDisallowedApplication("com.instagram.android");
// Set flag
_bVpnIsRunning = true;
}
So in the above instance, instagram should be the only blocked app, but all traffic appears to be blocked (can't use the chrome app, facebook, etc). Is there something I am missing in regards to this? Should I be specifying something before/after establishing the interface? Any help or direction would be greatly appreciated!
Note: In case it matters, I am targeting android 6.0 and higher. I can provide more source if required.

addDisallowedApplication:
By default, all applications are allowed access, except for those denied through this method. Denied applications will use networking as if the VPN wasn't running.
AddDisallowedApplication excludes the application from your VPNService and allows it to continue to use the "non-VPN" networking stack.
addAllowedApplication:
Adds an application that's allowed to access the VPN connection
Note: You can use an allowed or disallowed list, but not both at the same time.
So lets say we want to "block" any Chrome package from accessing the normal networking stack and redirect any Chrome apps from accessing the network via our "blocking" VPN, we can add all Chrome app package names to our VPNService implementation.
Note: there are 4(?) different Chrome apps, alpha, beta, etc.... so lets just block any package that has the name chrome in it, not really ideal, but for an example it works.
using (var pm = Application.Context.PackageManager)
{
var packageList = pm.GetInstalledPackages(0);
foreach (var package in packageList)
{
if (package.PackageName.Contains("chrome"))
{
Log.Debug(TAG, package.PackageName);
builder.AddAllowedApplication(package.PackageName);
}
}
}
After you .Establish() the VPN connection, all Chrome applications networking will be redirected to your VPNService and thus blocked.

Using a proxy with Selenium

for the past two days I've been trying to use a proxy with Selenium, that's not exactly the issue though. The issue is that the proxy is private meaning it needs authentication to use it (Username and Password) but I can't figure out how to do it.
I'm using a Firefox driver, with a profile like so:
FirefoxProfile firefoxProfile = new FirefoxProfile();
firefoxProfile.SetPreference("network.proxy.type", 1);
firefoxProfile.SetPreference("network.proxy.http", "23.95.115.87");
firefoxProfile.SetPreference("network.proxy.http_port", 80);
var driver = new FirefoxDriver(firefoxProfile);
driver.Navigate().GoToUrl("http://ipchicken.com");
I figured that it would ask me for the username and password (in a dialog box) yet nothing happens, it just navigates to the webpage, and displays my own IP. I can't find anything really on this, any help guys? Thank you so much.

I am not an expert in Selenium but I can help you in making your proxy authentication free.
If you are on Windows, download something like CC-Proxy ( Its free for a single user) and add your proxy as a cascading proxy. This will create a local proxy server on your computer which won't require username/password. Then you can use the local proxy server in selenium.
If you are on Linux, you can use wine to run CC-Proxy or you can use tinyproxy or squid ( it is an overkill).
Comment if you face problem in setting up CC-Proxy or tinyproxy.

Accessing the Ubuntu terminal from Mono

Background
I'm writing an web application so I can control an Ubuntu Server from a web site.
One idea I had was to run the 'screen' application from mono and redirect my input and output from there.
Running 'screen' from mono:
ProcessStartInfo info = new ProcessStartInfo("screen", "-m");
info.UseShellExecute = false;
info.RedirectStandardOutput = true;
info.RedirectStandardInput = true;
var p = new Process();
p.StartInfo = info;
p.Start();
var output = p.StandardOutput;
var input = p.StandardInput;
but running 'screen' with the RedirectStandardInput gives out the error:
Must be connected to a terminal
I've tried many different arguments and none seems to work with 'Redirecting Standard Input'
Other ideas for controlling a server will be greatly appreciated

I think this is the typical question in which you're asking how to implement your solution to a problem, instead of asking how to solve your problem. I don't think you should do hacky things like making a web app that tunnels the user actions to the server via a terminal.
I think you can bypass all that and, without writing a single line of code, take advantage of what the platform (Gtk+ in this case) already provides you:
You could run gnome-terminal in the server with the Broadway GDK backend. This way the gnome-terminal app will not run in the server, but open a web server on the port you specify. Later, you can use any WebSockets-enabled browser to control it.
This is the easiest and less hacky solution compared to the other ones offered so far. If you still are excited about using Mono for web development you still can, and you could embed this access in an iFrame or something.
(PS: If you don't want to depend on GTK being installed in the server; you could just use WebSockets in your client part of the webpage to be able to send events from the server to the client, and the library SSHNET to send the user's input directly through the wire.)

screen will need a terminal of some sort. It's also gigantically overkill.
You may wish to investigate the pty program from the Advanced Programming in the Unix Environment book (pty/ in the sources) to provide a pseudo-terminal that you can drive programmatically. (You'd probably run the pty program as-provided and write your driver in Mono if you're so inclined.) (The pty program will make far more sense if studied in conjunction with the book.)
The benefit to using the pty program, or functionality similar to it, is that you'd properly handle programs such as passwd that open("/dev/tty") to prompt the user for a password. If you simply redirect standard IO streams via pipe() and dup2() system calls, you won't have a controlling terminal for the programs that need one. (This is still a lot of useful programs but not enough to be a remote administration tool.)
There may be a Mono interface to the pty(7) system; if so, it may be more natural to use it than to use the C API, but the C API is what does the actual work, so it may be easier to just write directly in the native language.

A different approach to solve the same problem is shellinabox. Also interesting is this page from the anyterm website that compares different products that implement this kind of functionality.
Using shellinabox is very simple:
# ./shellinaboxd -s /:LOGIN
(this is the example given on their website) will start a webserver (on in your case the Ubuntu server). When you point your browser to http://yourserver:4200 you'll see a login screen, just like you would see when opening a session with ssh/putty/telnet/... but in your browser.
You could provide the required remote access functionality to the server's shell by just including an iframe that points to that service in your application's webpage.

Can a WebServiceHost be changed to avoid the use of HttpListener?

I am looking for a way to use a WCF WebServiceHost without having to rely on the HttpListener class and it's associated permission problems (see this question for details).
I'm working on a application which communicates locally with another (third-party) application via their REST API.
At the moment we are using WCF as an embedded HTTP server. We create a WebServiceHost as follows:
String hostPath = "http://localhost:" + portNo;
WebServiceHost host = new WebServiceHost(typeof(IntegrationService), new Uri(hostPath));
// create a webhttpbinding for rest/pox and enable cookie support for session management
WebHttpBinding webHttpBinding = new WebHttpBinding();
webHttpBinding.AllowCookies = true;
ServiceEndpoint ep = host.AddServiceEndpoint(typeof(IIntegrationService), webHttpBinding, "");
host.Open()
ChannelFactory<IIntegrationService> cf = new ChannelFactory<IIntegrationService>(webHttpBinding, hostPath);
IIntegrationService channel = cf.CreateChannel();
Everything works nicely as long as our application is run as administrator. If we run our application on a machine without administrative privileges the host.Open() will throw an HttpListenerException with ErrorCode == 5 (ERROR_ACCESS_DENIED).
We can get around the problem by running httpcfg.exe from the command line but this is a one-click desktop application and that's not really as long term solution for us.
We could ditch WCF and write our own HTTP server but I'd like to avoid that if possible.
What's the easiest way to replace HttpListener with a standard TCP socket while still using all of the remaining HTTP scaffolding that WCF provides?

Your problem is not related to HttpListener.
Your problem is:
* You have a oneClick application with limited permissions that
* Tries to open a Server port.
This is a contradiction. An untrusted limited permission application should NOT OPEN A SERVER PORT. This is why this is not allowed per definition.
Have you tried opening a normal socket port? It should not work either.
In general, limited trust end user applications should not host a web service ;)
That said, I ahve been in a similar situation trying to use WCF in a driver communication scenario - thank heaven my application runs with full permission.

You can easily compose your own stack via CustomBinding, using the higher level protocol stuff "as is", and rolling your own version of HttpTransport that isn't backed by HttpListener or IIS. Do-able, sure, but it's a lot of work. Take the existing HttpTransport bits apart with Reflector- there are a LOT of moving parts in there. You could probably hack up a simple PoC over Socket in a day or two if you don't need anything fancy like HTTPS or chunking, but making it robust will be tricky. Here's a good wrapup of a bunch of resources (may be a bit dated now).

You could also look at ripping apart enough of Cassini to make it hostable in your app, and loading the WCF pipeline in there (via .svc files and the service activation handler)- it'd require writing very little new code that way, but still give you a fairly robust and tested webserver.