Develop Reference

Multi hop SSH through SSH.NET in C#

I am doing SSH to a Linux machine and again from there want to SSH to another Linux machine to carry out few Perforce tasks.
using (SshClient ssh = new SshClient("ip address","username", "pwd"))
{
ssh.Connect();
command = ssh.CreateCommand("ssh hostname");
result = command.Execute();
Console.WriteLine(result);
}
Where the ssh hostname is a password less ssh. How can I control the second SSH session and pass commands to it?
Even explored the CreateShell function, but seems like it is not suggested for automation.

In general, trying to automate ssh command is a bad design.
You better use a port forwarding (aka SSH tunnel) to implement the "hop".
var firstClient =
new SshClient(firstHostName, firstUserName, firstPassword);
firstClient.Connect();
var port = new ForwardedPortLocal("127.0.0.1", secondHostName, 22);
firstClient.AddForwardedPort(port);
port.Start();
var secondClient =
new SshClient(port.BoundHost, (int)port.BoundPort, secondUserName, secondPassword);
secondClient.Connect();
var command = secondClient.CreateCommand("ls");
var result = command.Execute();
Console.WriteLine(result);
There are some cases, when automating the ssh is acceptable (while still not ideal). E.g. because there's an authentication to the second host set up on the first one. I.e. there might be private key in the .ssh folder and you are not allowed to transfer that key to your client machine.
Even then, try talking to the system Administrator to find a better solution. The private key is still accessible using the credentials contained in your application, so it's not protected any better, had the private key itself been contained directly in the application.
Anyway, ssh can accept a command on its command line, like:
command = ssh.CreateCommand("ssh hostname command");
result = command.Execute();
Console.WriteLine(result);

Getting al ip's

So, i'm new to C# and visual studio and stuff. But i searched arround for how to get all ip's, Like you see in the Windows Firewall app. But I can't find any thing to get started with. I saw alot of posts about Dns, And stuff So i got this:
private void ip()
{
StringBuilder sb = new StringBuilder();
// Get host name
String strHostName = Dns.GetHostName();
// Find host by name
IPHostEntry iphostentry = Dns.GetHostByName(strHostName);
// Enumerate IP addresses
foreach (IPAddress ipaddress in iphostentry.AddressList)
{
sb.AppendLine(strHostName + " - " + ipaddress);
label1.Text = sb.ToString().Replace(Environment.NewLine, "\n");
}
}
But I only get 4 ip's but i want all ip's currently connecting to my pc.
(And an i know there are alot of posts about this, but i'm searching for an answer for an beginning programmer to understand)
Could anybody help me?
Thanks!

That code you show gets the IPs assigned to the current machine.
What it sounds like you want is the equivalent of running netstat on the command line (get all active connections). This question should get you started: How to determine tcp port used by Windows process in C#
Basically you use GetActiveTcpConnections.

RDP to ip address from onclick menuItem #c VS

I'm trying to launch a remote desktop session to a specified IP on an onClick function on a menuItem in VS.
private void NAMEHEREToolStripMenuItem_Click(object sender, EventArgs e)
{
// launch remote desktop to 192.168.0.1
}
So I click NAMEHERE and it should open remote desktop and automatically connect to the IP I've given it. How can I do this? I've googled different things but cant quite find what I want.
Thanks!

On Windows you can launch the remote desktop program with the /v argument, like this:
mstsc.exe /v 192.168.0.1
you can also define a port after the IP if needed: 192.168.0.1:1234 for example.
For all arguments, launch it in command propmt:
mstsc.exe -?

and to start the process:
// launch remote desktop to 192.168.0.1
var ipAddress = "192.168.0.1";
var pinfo = new System.Diagnostics.ProcessStartInfo("mstsc.exe");
pinfo.Arguments = "/v " + ipAddress;
Process.Start(pinfo);

failing to get IPv6 remotely

I am trying to fetch IPs of remote machine. But my code fails to collect IPv6 remotely. The code runs fine when run locally. Following is my sample code
System.Net.IPHostEntry hostEntryComputer;
try
{
hostEntryComputer = System.Net.Dns.GetHostEntry(computerName);
foreach (System.Net.IPAddress addr in hostEntryComputer.AddressList)
{
string temp = addr.ToString();
Console.WriteLine("IP: " + temp);
}
}
catch(Exception ex)
{
Console.WriteLine(ex.Message);
}
any help would be appreciated.

From MSDN: "IPv6 addresses are filtered from the results of the GetHostEntry method if the local computer does not have IPv6 installed. As a result, it is possible to get back an empty IPHostEntry instance if only IPv6 results where available for the hostNameOrAddress.parameter."
Follow those tutorials to enable it on your local machine:
Windows XP
Windows Vista/7

How to execute process on remote machine, in C#

How can I start a process on a remote computer in c#, say computer name = "someComputer", using System.Diagnostics.Process class?
I created a small console app on that remote computer that just writes "Hello world" to a txt file, and I would like to call it remotely.
Console app path: c:\MyAppFolder\MyApp.exe
Currently I have this:
ProcessStartInfo startInfo = new ProcessStartInfo(string.Format(#"\\{0}\{1}", someComputer, somePath);
startInfo.UserName = "MyUserName";
SecureString sec = new SecureString();
string pwd = "MyPassword";
foreach (char item in pwd)
{
sec.AppendChar(item);
}
sec.MakeReadOnly();
startInfo.Password = sec;
startInfo.UseShellExecute = false;
Process.Start(startInfo);
I keep getting "Network path was not found".

Can can use PsExec from http://technet.microsoft.com/en-us/sysinternals/bb897553.aspx
Or WMI:
object theProcessToRun() = { "YourFileHere" };
ManagementClass theClass = new ManagementClass(#"\\server\root\cimv2:Win32_Process");
theClass.InvokeMethod("Create", theProcessToRun);

Use one of the following:
(EDIT) Remote Powershell
WMI (see Ivan G's answer)
Task Scheduler API (http://msdn.microsoft.com/en-us/library/windows/desktop/aa383606%28v=vs.85%29.aspx)
PsExec
WshRemote object with a dummy script. Chances are, it works via DCOM, activating some of scripting objects remotely.
Or if you feel like it, inject your own service or COM component. That would be very close to what PsExec does.
Of all these methods, I prefer task scheduler. The cleanest API of them all, I think. Connect to the remote task scheduler, create a new task for the executable, run it. Note: the executable name should be local to that machine. Not \servername\path\file.exe, but c:\path\file.exe. Delete the task if you feel like it.
All those methods require that you have administrative access to the target machine.
ProcessStartInfo is not capable of launching remote processes.

According to MSDN, a Process object only allows access to remote processes not the ability to start or stop remote processes. So to answer your question with respect to using this class, you can't.

An example with WMI and other credentials as the current process, on default it used the same user as the process runs.
var hostname = "server"; //hostname or a IpAddress
var connection = new ConnectionOptions();
//The '.\' is for a local user on the remote machine
//Or 'mydomain\user' for a domain user
connection.Username = #".\Administrator";
connection.Password = "passwordOfAdministrator";
object[] theProcessToRun = { "YourFileHere" }; //for example notepad.exe
var wmiScope = new ManagementScope($#"\\{hostname}\root\cimv2", connection);
wmiScope.Connect();
using (var managementClass = new ManagementClass(wmiScope, new ManagementPath("Win32_Process"), new ObjectGetOptions()))
{
managementClass.InvokeMethod("Create", theProcessToRun);
}

I don't believe you can start a process through a UNC path directly; that is, if System.Process uses the windows comspec to launch the application... how about you test this theory by mapping a drive to "\someComputer\somePath", then changing your creation of the ProcessStartInfo to that? If it works that way, then you may want to consider temporarily mapping a drive programmatically, launch your app, then remove the mapping (much like pushd/popd works from a command window).