#Requires -version 2.0


<#
 Script: Test-Port.ps1
 Version: 2.0
 Author: Jeffery Hicks
    http://jdhitsolutions.com/blog
    http://twitter.com/JeffHicks
    http://www.ScriptingGeek.com
 Date: 5/31/2011
 Keywords:
 Comments:
 A port scanning function that can be used in the pipeline. The
 underlying .NET classes have useful information.

 The original version of this script is from
 http://theadminguy.wordpress.com/2009/04/30/portscan-with-powershell/

 "Those who forget to script are doomed to repeat their work."

  ****************************************************************
  * DO NOT USE IN A PRODUCTION ENVIRONMENT UNTIL YOU HAVE TESTED *
  * THOROUGHLY IN A LAB ENVIRONMENT. USE AT YOUR OWN RISK.  IF   *
  * YOU DO NOT UNDERSTAND WHAT THIS SCRIPT DOES OR HOW IT WORKS, *
  * DO NOT USE IT OUTSIDE OF A SECURE, TEST SETTING.             *
  ****************************************************************
#>

Function Test-Port {

<#
.SYNOPSIS
Test for an open port
.DESCRIPTION
This function uses the .NET framework to test if a given port is open on a computer. It will return a custom object to the pipeline.
.PARAMETER Computername
The name of the computer to test. The default is the localhost.
.PARAMETER Ports
An array of ports to test. The default is 21,22,23,80,443 and 3389
.PARAMETER WhatIf
Simulate what would happen if you ran the function
.PARAMETER Confirm
Confirm that you want to test the ports
.EXAMPLE
PS C:\> Test-Port jdhit-dc01 -ports 21,80,389,3389

Port         : 21
Open         : False
TTL          : -1
Computername : JDHIT-DC01
RemoteIP     : 

Port         : 80
Open         : True
TTL          : 128
Computername : JDHIT-DC01
RemoteIP     : 172.16.10.1

Port         : 389
Open         : True
TTL          : 128
Computername : JDHIT-DC01
RemoteIP     : 172.16.10.1

Port         : 3389
Open         : True
TTL          : 128
Computername : JDHIT-DC01
RemoteIP     : 172.16.10.1

Scan the computer for the specified ports.
.EXAMPLE
PS C:\> get-content computers.txt | Test-Port -port 80 | Where {$_.Open} | Out-File Open80.txt

Scan all the computers in computers.txt for port 80 and save the results for computers listening
on port 80 to a text file.
.NOTES
NAME        :  Test-Port
VERSION     :  2.0   
LAST UPDATED:  5/31/2011
AUTHOR      :  SERENITY\Jeff
.LINK
http://jdhitsolutions.com/blog/2011/05/test-port-2-0/
.LINK
Test-Connection 
.INPUTS
Strings
.OUTPUTS
Custom object
#>

[cmdletbinding(SupportsShouldProcess=$True,ConfirmImpact="Low")]

Param(
[Parameter(Position=0,ValueFromPipeline=$True,ValueFromPipelineByPropertyName=$True)]
[ValidateNotNullorEmpty()]
[string[]]$Computername=$env:computername,
[array]$Ports=@("21","22","23","25","80","443","3389")
)

Begin { 
  #set values for Write-Progress
  Write-Verbose "$(Get-Date) Starting $($myinvocation.mycommand)"
  Write-Verbose "$(Get-Date) Scannning for ports $($ports  -as [string])"
  $activity="Port Scan"
}

Process {

 Foreach ($computer in $computername) {
 
 #whatif
 if ($pscmdlet.ShouldProcess($($computer.ToUpper()))) {
  $status="Scanning $computer"
  Write-Verbose "$(Get-Date) $status"
  $i=0
    
       foreach ($port in $ports) { 
       $i++
        Write-Progress -Activity $activity -status $status `
        -currentoperation "port $port" -percentcomplete (($i/$ports.count)*100)
       
        Try {
            #create the TCPClient object      
            $tcp=New-Object System.Net.Sockets.TcpClient($computer, $port) -ErrorAction Stop
        }
        Catch {
            Write-Verbose "$(Get-Date) Connection refused"
        }
        if ($tcp.client.connected) 
        {    
            [string]$rep=$tcp.client.RemoteEndPoint
            [string]$ip=$rep.substring(0,$rep.indexof(":"))
                      
            $PortOpen=$True
            $TTL=$($tcp.client.ttl)
            $RemoteIP=$ip
           
        }
        else 
        {
            Write-Verbose "$(Get-Date) $($computer.ToUpper()) not open on port: $port"
            $PortOpen=$False
            $TTL=-1
            $RemoteIP=$Null
        }  #end Else
         
            #disconnect the socket connection if open
            if ($PortOpen)
            {
                Write-Verbose "$(Get-Date) Disconnecting from $($computer.ToUpper())"
                $tcp.client.disconnect($False)
            }
            
            #write a custom object to the pipeline
            New-Object -TypeName PSObject -Property @{
              Computername=$Computer.ToUpper()
              Port=$Port
              Open=$PortOpen
              TTL=$TTL
              RemoteIP=$RemoteIP
            }
            
        } #end foreach $port
        
        #dispose and disconnect
        if ($tcp)
        {
            $tcp.close()
        }
     } #if shouldprocess   
     } #foreach $computer
} #end process

End { 
    Write-Progress -Activity $activity -status "Complete" -Completed
    Write-Verbose "$(Get-Date) Ending $($myinvocation.mycommand)"
 }#end
         
} #end function

#Set an optional alias
#Set-Alias -Name tp -Value Test-Port