Monday, February 23, 2009

WebServer investigated

I recently spend some time playing around with creating a bunch of scripts to monitor changes in a web page. While doing this I needed to determine what kind of webserver a given site was hosted on. This is a somewhat simplified version of my solution:

function Get-WebServer {
    param ($target)
    if (-not ($target -like "http://*")) {
        $target = "http://" + $target
    }
    $wr = [System.Net.WebRequest]::Create($target)
    $wr.UserAgent = "InterwebExploder 10.0 RC1 - 'Titanic'"
    $header = $wr.GetResponse()
    Write-host "$target"
    $header | select Server, LastModified, ProtocolVersion, ResponseUri | Format-List
}

Please note that proxies and various other issues can ruin the function.
To use the function, simply call it with the name of the target url:

Get-WebServer "www.blogspot.com"

Monday, February 09, 2009

CLI Menu in PowerShell


There are a lot of WPF-based PowerShell menu functions and demos available in various places, but for some reason I feel that PowerShell really needs a good, ol' fashion CLI menu.

So, here is a quick, sort of hack'ish CLI menu for PowerShell (dont worry, I just made up the individual menu options - can you tell I just reread BOFH recently?).

Use the up and down arrows to navigate the menu, and press ENTER to select.

function DrawMenu {
    ## supportfunction to the Menu function below
    param ($menuItems, $menuPosition, $menuTitel)
    $fcolor = $host.UI.RawUI.ForegroundColor
    $bcolor = $host.UI.RawUI.BackgroundColor
    $l = $menuItems.length + 1
    cls
    $menuwidth = $menuTitel.length + 4
    Write-Host "`t" -NoNewLine
    Write-Host ("*" * $menuwidth) -fore $fcolor -back $bcolor
    Write-Host "`t" -NoNewLine
    Write-Host "* $menuTitel *" -fore $fcolor -back $bcolor
    Write-Host "`t" -NoNewLine
    Write-Host ("*" * $menuwidth) -fore $fcolor -back $bcolor
    Write-Host ""
    Write-debug "L: $l MenuItems: $menuItems MenuPosition: $menuposition"
    for ($i = 0; $i -le $l;$i++) {
        Write-Host "`t" -NoNewLine
        if ($i -eq $menuPosition) {
            Write-Host "$($menuItems[$i])" -fore $bcolor -back $fcolor
        } else {
            Write-Host "$($menuItems[$i])" -fore $fcolor -back $bcolor
        }
    }
}

function Menu {
    ## Generate a small "DOS-like" menu.
    ## Choose a menuitem using up and down arrows, select by pressing ENTER
    param ([array]$menuItems, $menuTitel = "MENU")
    $vkeycode = 0
    $pos = 0
    DrawMenu $menuItems $pos $menuTitel
    While ($vkeycode -ne 13) {
        $press = $host.ui.rawui.readkey("NoEcho,IncludeKeyDown")
        $vkeycode = $press.virtualkeycode
        Write-host "$($press.character)" -NoNewLine
        If ($vkeycode -eq 38) {$pos--}
        If ($vkeycode -eq 40) {$pos++}
        if ($pos -lt 0) {$pos = 0}
        if ($pos -ge $menuItems.length) {$pos = $menuItems.length -1}
        DrawMenu $menuItems $pos $menuTitel
    }
    Write-Output $($menuItems[$pos])
}

Example:

$bad = "Format c:","Send spam to boss","Truncate database *","Randomize user password","Download dilbert","Hack local AD"
$selection = Menu $bad "WHAT DO YOU WANNA DO?"
Write-Host "YOU SELECTED : $selection ... DONE!`n"

Another Example:


$options = "Dir","Ping", "Ipconfig"
$selection = Menu $options "CHOOSE YOUR COMMAND:"
Switch ($selection) {
    "Dir" {Invoke-Expression "Dir C:\";break}
    "Ping" {Invoke-Expression "Ping 127.0.0.1";break}
    "Ipconfig" {Invoke-Expression "Ipconfig";break}
}

Trapping errors in Powershell

I just stumbled across this sweet little introduction to trapping errors in PowerShell:
http://powershell.com/cs/blogs/tobias/archive/2008/09/29/trapping-errors.aspx

Saturday, February 07, 2009

Retrieveing the Windows Product Key

I was recently asked if I knew of a tool capable of retrieving the Product Key from an installed instance of Windows Vista. While there are several such tools available (use google), my solution - naturally - was to write a PowerShell script that can do just that.

The script below is based on information from "The Custodian" on Everything2: http://everything2.com/node/1058074

I've tested the function against Windows XP, Vista x64 and Windows 7 x64, as well as Windows Server 2003 and Windows Home Server. As long at the the user executing the script has sufficient privileges, and no firewall is blocking remote access to the registry/WMI the script appears to work fine.

function Get-WindowsKey {
    ## function to retrieve the Windows Product Key from any PC
    ## by Jakob Bindslet (jakob@bindslet.dk)
    param ($targets = ".")
    $hklm = 2147483650
    $regPath = "Software\Microsoft\Windows NT\CurrentVersion"
    $regValue = "DigitalProductId"
    Foreach ($target in $targets) {
        $productKey = $null
        $win32os = $null
        $wmi = [WMIClass]"\\$target\root\default:stdRegProv"
        $data = $wmi.GetBinaryValue($hklm,$regPath,$regValue)
        $binArray = ($data.uValue)[52..66]
        $charsArray = "B","C","D","F","G","H","J","K","M","P","Q","R","T","V","W","X","Y","2","3","4","6","7","8","9"
        ## decrypt base24 encoded binary data
        For ($i = 24; $i -ge 0; $i--) {
            $k = 0
            For ($j = 14; $j -ge 0; $j--) {
                $k = $k * 256 -bxor $binArray[$j]
                $binArray[$j] = [math]::truncate($k / 24)
                $k = $k % 24
            }
            $productKey = $charsArray[$k] + $productKey
            If (($i % 5 -eq 0) -and ($i -ne 0)) {
                $productKey = "-" + $productKey
            }
        }
        $win32os = Get-WmiObject Win32_OperatingSystem -computer $target
        $obj = New-Object Object
        $obj | Add-Member Noteproperty Computer -value $target
        $obj | Add-Member Noteproperty Caption -value $win32os.Caption
        $obj | Add-Member Noteproperty CSDVersion -value $win32os.CSDVersion
        $obj | Add-Member Noteproperty OSArch -value $win32os.OSArchitecture
        $obj | Add-Member Noteproperty BuildNumber -value $win32os.BuildNumber
        $obj | Add-Member Noteproperty RegisteredTo -value $win32os.RegisteredUser
        $obj | Add-Member Noteproperty ProductID -value $win32os.SerialNumber
        $obj | Add-Member Noteproperty ProductKey -value $productkey
        $obj
    }
}

Use the function to retrieve the Product Key from the local PC:

Get-WindowsKey

Or to retrieve the Product Key from one or more PCs (locally or remotely):

Get-WindowsKey "pc1", "pc2", "server999", "server777"

Remeber that the output from the function is a standard PowerShell object, so you can pipe into sort-object, format-table or mayby ConvertTo-HTML ...

Thursday, February 05, 2009

T-SQL query with object-based result

Two small functions that can be used to make an T-SQL query, and have the result returned as a standard PowerShell object. This can be useful if - for some reason - you would like to use Sort-Object or similar on the result afterwards.

function ConnectSQL {
    Param ($server, $query, $database)
    $conn = new-object ('System.Data.SqlClient.SqlConnection')
    $connString = "Server=$server;Integrated Security=SSPI;Database=$database"
    $conn.ConnectionString = $connString
    $conn.Open()
    $sqlCmd = New-Object System.Data.SqlClient.SqlCommand
    $sqlCmd.CommandText = $query
    $sqlCmd.Connection = $conn
    $Rset = $sqlCmd.ExecuteReader()
    ,$Rset ## The comma is used to create an outer array, which PS strips off automatically when returning the $Rset
}

function QuerySQL {
    Param ($server, $query, $database = "master")
    $data = ConnectSQL $server $query $database
    while ($data.read() -eq $true) {
        $max = $data.FieldCount -1
        $obj = New-Object Object
        For ($i = 0; $i -le $max; $i++) {
            $name = $data.GetName($i)
            $obj | Add-Member Noteproperty $name -value $data.GetValue($i)
     }
     $obj
    }
}

The function is used like this:

QuerySQL "MyServer" "SELECT * FROM sysdatabases"

Or maybe more like this:

$data = QuerySQL "MyServer" "SELECT * FROM sysdatabases"
$data | Format-Table -AutoSize