PortScan

function Get-OpenPorts {
    [CmdletBinding()]
    Param(
            [parameter(
                    Mandatory = $true
                ,   HelpMessage = "Insert IP to scan"
                ,   Position = 0)]
            [string]$ip
        ,   [parameter(
                    Mandatory = $true
                ,   HelpMessage = "Insert ports to scan"
                ,   Position = 1)]
            [int[]]$portArray
    )

    begin{
        #Check if IP is valid
        try {
            [System.Net.IPAddress]$iptest = $ip
        }
        catch {
            $target = $ip
            try {
                $dnstest = [System.Net.Dns]::GetHostAddresses($ip).ipaddresstostring
            } catch {
                Write-Host -ForegroundColor Red "Host: '$ip' not found"
                break
            }
            [System.Net.IPAddress]$ip = $dnstest
        }
    }

    process{
        $openPorts = New-Object -TypeName System.Collections.Generic.List[int]

        $runTime = Measure-Command {
            $counter = 0
            foreach ($port in $portArray) {

                    $counter++
                    Write-Progress -Activity "Scanning Port: $port progress: $($counter)/$($portArray.Count)" -Status "Found $($openPorts.Count) open ports" -PercentComplete (($counter / $portArray.Count) * 100)

                    $TCP = New-Object -TypeName System.Net.Sockets.TcpClient

                    $result = $TCP.BeginConnect($ip,$port,$null,$null)
                    $success = $result.AsyncWaitHandle.WaitOne(15)

                    if ($success){
                        $openPorts.Add($port)
                    }

                    $TCP.Dispose()
                }
            }

        $Propertys = [ordered]@{
            'Destination' = $target
            'ScanTime' = $runTime.ToString("hh\:mm\:ss\,ff")
            'OpenPorts' = $openPorts
        }
        $returnObject = New-Object -TypeName PsObject -Property $Propertys
        return $returnObject
    }
}