I wrote this basic powershell script. The script tracks your laptop's external IP address, and if it changes it will send you an email with the new external IP and a traceroute. The intended purpose is to help locate your laptop if it is lost or stolen. An ISP would be able to determine who was using the IP.
- To set it up, you first need to enable your execution policy to allow powershell scripts, this can be done from an elevated powershell prompt Set-ExecutionPolicy -Scope LocalMachine
- Run the script once manually this will allow you to configure the email settings. The password is stored as a powershell secure string
- Setup a reoccurring scheduled task as SYSTEM
Code:
$configdir = "$env:ProgramData\Monitor"
$credfile = "$configdir\cred.txt"
$configfile = "$configdir\config.txt"
$ipfile = "$configdir\ip.txt"
Function Get-ExternalIPAddress
{
$data = (Invoke-WebRequest -Uri "whatismyip.org" -UseBasicParsing).Content
ExtractValidIPAddress -String $data
}
Function ExtractValidIPAddress($String)
{
$IPregex=‘(?<Address>((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?))’
If ($String -Match $IPregex) {$Matches.Address}
}
$ip = Get-ExternalIPAddress
#Setup configuration
If (!(Test-Path -Path $configdir))
{
#Prompt for configuration information
New-Item -Path $configdir -ItemType Directory
"Configuration folder missing, please enter setup info..."
$server = Read-Host -Prompt "Enter email server"
$port = Read-Host -Prompt "Enter email port"
$emailto = Read-Host -Prompt "Enter To email address"
$emailfrom = Read-Host -Prompt "Enter From email address"
$user = Read-Host -Prompt "Enter email username"
Write-Host 'Enter your password:' -ForegroundColor Red
$pass = Read-Host -AsSecureString | ConvertFrom-SecureString | Out-File $credfile
$ip = Get-ExternalIPAddress
#Create Configuration File
$monitor_file = New-Item -Path $configfile -ItemType File
Out-File -FilePath $monitor_file.FullName -Append -InputObject ("server:$server")
Out-File -FilePath $monitor_file.FullName -Append -InputObject ("port:$port")
Out-File -FilePath $monitor_file.FullName -Append -InputObject ("username:$user")
Out-File -FilePath $monitor_file.FullName -Append -InputObject ("from:$emailto")
Out-File -FilePath $monitor_file.FullName -Append -InputObject ("from:$emailfrom")
#Create IP File
New-Item -Path $ipfile -ItemType File
Out-File -FilePath $ipfile -InputObject ($ip)
} Else
{
$server =""
$port = ""
$to = ""
$from = ""
$user = ""
#Loop to detect connected network adapters
#Wait for an adapter to be connected
$nic = 0
While( $nic -eq 0 )
{
$obj = GWMI -Class Win32_NetworkAdapter -Filter "netconnectionstatus = 2"
$nic = $obj.Count
}
#Compare recorded IP with curent
#Script will exit if the IP has not changed
$savedip = Get-Content $ipfile
$currentip = Get-ExternalIPAddress
If (($savedip -eq $currentip))
{
"External IP has not changed."
Exit
}
#Read configuration file to configure
#sending email
$config = Get-Content $configfile
Foreach ($c In $config)
{
If($c.Contains("server:"))
{
$split = $c.Split(":")
$server = $split[1]
}
If($c.Contains("port:"))
{
$split = $c.Split(":")
$port = $split[1]
}
If($c.Contains("from:"))
{
$split = $c.Split(":")
$from = $split[1]
}
If($c.Contains("to:"))
{
$split = $c.Split(":")
$to = $split[1]
}
If($c.Contains("username:"))
{
$split = $c.Split(":")
$user = $split[1]
}
}
#Create Credential object for sending email
$secpass = Get-Content C:\ProgramData\Monitor\cred.txt | ConvertTo-SecureString
$PSCred = New-Object -TypeName System.Management.Automation.PSCredential -ArgumentList $user,$secpass
#Form html message body
$header = "<!DOCTYPE html>`r<html>`r<head>`r<meta charset=`"UTF-8`"></head>"
$body += $header
$body = "<body>`r<p>External IP is now: $ip<br>TraceRoute<br>"
$trace = tracert 8.8.8.8
ForEach($t In $trace) { $body += "$t<br>" }
$body += "</p></body></html>"
#send email
Send-MailMessage -SmtpServer $server -Port:$port -From $from -To $to `
-Subject "External IP has changed" -BodyAsHtml $body -Credential $PSCred -UseSsl
} Last edited:
