[SSH] [Bugfix] Fix RDP connection (#22188)

* Move logic to get rdp local port to a property

* Update help file message for -Force parameter

* Add bugfix to changelog

* Update ChangeLog.md

---------

Co-authored-by: Vincent Dai <[email protected]>

Author: vthiebaut10

src/Ssh/Ssh/ChangeLog.md

@@ -19,8 +19,9 @@
 -->
 
 ## Upcoming Release
-* Support updating Service Configuration for Arc resources at runtime.
+* Supported updating Service Configuration for Arc resources at runtime.
     - Owners/Contributors can change what port is allowed for SSH connection at runtime by providing the -Port parameter and confirming the operation when prompted.
+* Fixed bug in the RDP feature in the Enter-AzVM cmdlet.
 
 ## Version 0.1.2
 * The SSH Proxy required for connection to Arc resources must be installed by the user as part of the Az.Ssh.ArcProxy PowerShell module

src/Ssh/Ssh/Common/SshBaseCmdlet.cs

@@ -339,7 +339,7 @@ private ResourceManagementClient ResourceManagementClient
         [Parameter(Mandatory = false)]
         public virtual SwitchParameter PassThru { get; set; }
 
-        [Parameter(Mandatory = false, HelpMessage = "When connecting to Arc resources, do not prompt for confirmation before updating the Service Configuration of the Connection Endpoint to match the target port or to install Az.Ssh.ArcProxy module from Gallery, if needed.")]
+        [Parameter(Mandatory = false, HelpMessage = "When connecting to Arc resources, do not prompt for confirmation before updating the allowed port for SSH connection in the Connection Endpoint to match the target port or to install Az.Ssh.ArcProxy module from the PowerShell Gallery, if needed.")]
         public SwitchParameter Force { get; set; }
 
         #endregion

src/Ssh/Ssh/SshCommands/EnterAzVMCommand.cs

@@ -25,6 +25,7 @@
 using System.Text.RegularExpressions;
 using Microsoft.Azure.Commands.Ssh.Properties;
 using Microsoft.Azure.PowerShell.Ssh.Helpers.HybridConnectivity.Models;
+using Microsoft.Azure.PowerShell.Cmdlets.Ssh.Common;
 
 namespace Microsoft.Azure.Commands.Ssh
 {
@@ -55,7 +56,6 @@ public override string KeysDestinationFolder
         #endregion
 
         #region fields
-        private int rdpLocalPort;
         private EndpointAccessResource relayInfo;
         #endregion
 
@@ -64,6 +64,25 @@ public override string KeysDestinationFolder
         private const int ServiceConfigDelayInSec = 15;
         #endregion
 
+        #region Properties
+        private int RdpLocalPort
+        {
+            get
+            {
+                if (_rdpLocalPort == 0)
+                {
+                    TcpListener listener = new TcpListener(IPAddress.Loopback, 0);
+                    listener.Start();
+                    _rdpLocalPort = ((IPEndPoint)listener.LocalEndpoint).Port;
+                    listener.Stop();
+                }
+
+                return _rdpLocalPort;
+            }
+        }
+        private int _rdpLocalPort = 0;
+        #endregion
+
         public override void ExecuteCmdlet()
         {
             base.ExecuteCmdlet();
@@ -178,12 +197,6 @@ private int StartRDPConnection(Process sshProcess)
 
             try
             {
-                // Get an open local port to act an a listener
-                TcpListener listener = new TcpListener(IPAddress.Loopback, 0);
-                listener.Start();
-                rdpLocalPort = ((IPEndPoint)listener.LocalEndpoint).Port;
-                listener.Stop();
-
                 sshProcess.StartInfo.RedirectStandardError = true;
                 sshProcess.Start();
 
@@ -207,7 +220,7 @@ private int StartRDPConnection(Process sshProcess)
 
                     Process rdpProcess = new Process();
                     rdpProcess.StartInfo.FileName = rdpCommand;
-                    rdpProcess.StartInfo.Arguments = $"/v:localhost:{rdpLocalPort}";
+                    rdpProcess.StartInfo.Arguments = $"/v:localhost:{RdpLocalPort}";
                     rdpProcess.Start();
                     rdpProcess.WaitForExit();
                     success = rdpProcess.ExitCode;
@@ -398,7 +411,7 @@ private string BuildArgs()
             if (Rdp)
             {
                 argList.Add("-L");
-                argList.Add($"{rdpLocalPort}:localhost:3389");
+                argList.Add($"{RdpLocalPort}:localhost:3389");
                 argList.Add("-N");
             }
 

src/Ssh/Ssh/help/Enter-AzVM.md

@@ -125,7 +125,7 @@ Accept wildcard characters: False
 ```
 
 ### -Force
-When connecting to an Arc resource, do not ask for confirmation before updating the Service Configuration of the Connection Endpoint to match the target port.
+When connecting to Arc resources, do not prompt for confirmation before updating the allowed port for SSH connection in the Connection Endpoint to match the target port or to install Az.Ssh.ArcProxy module from the PowerShell Gallery, if needed.
 
 ```yaml
 Type: System.Management.Automation.SwitchParameter

src/Ssh/Ssh/help/Export-AzSshConfig.md

@@ -143,7 +143,7 @@ Accept wildcard characters: False
 ```
 
 ### -Force
-When connecting to an Arc resource, do not ask for confirmation before updating the Service Configuration of the Connection Endpoint to match the target port.
+When connecting to Arc resources, do not prompt for confirmation before updating the allowed port for SSH connection in the Connection Endpoint to match the target port or to install Az.Ssh.ArcProxy module from the PowerShell Gallery, if needed.
 
 ```yaml
 Type: System.Management.Automation.SwitchParameter