SP3269

SP3269

# Output Linux environment from Terraform

provider "local" {}

data "local_file" "env" {
  filename = "/proc/1/environ"
}

output "env" {
  value = data.local_file.env.content

SP3269

#! /usr/bin/pwsh -nop
$j = Get-Content "./Gsuite.json" | ConvertFrom-JSON
$priv = $j.private_key
$pub = (Invoke-RestMethod $j.client_x509_cert_url).($j.private_key_id)
$rnd = Get-Random 1000001
$priv | Out-File ".\priv$rnd.key"
$pub | Out-File ".\pub$rnd.cer"
openssl pkcs12 -export -in "pub$rnd.cer" -inkey "priv$rnd.key" -out "pfx$rnd.p12" -password pass:notasecret

SP3269

# Using curl to measure TLS negotiation time, as a proxy of PKCS #11 performance
# https://blog.cloudflare.com/a-question-of-timing/

function Get-ConnectionTimes ([string] $Uri) {
    $curl = curl -w "%{time_namelookup},%{time_connect},%{time_appconnect}\n" -s -o /dev/null $Uri
    $namelookup,$connect,$appconnect = $curl -split ","
    $res = [PSCustomObject]@{
        namelookup = [float]$namelookup
        connect = [float]$connect
        appconnect = [float]$appconnect

SP3269

# JWT signature verification
# $jwt should contain the JWT as a string

$parts = $jwt.Split('.')

$SHA256 = New-Object Security.Cryptography.SHA256Managed
$computed = $SHA256.ComputeHash([System.Text.Encoding]::UTF8.GetBytes($parts[0]+"."+$parts[1]))

# Method A - just using X509Certificate2. TODO: initialise from file, no private key
# Reference: https://blogs.msdn.microsoft.com/alejacma/2008/06/25/how-to-sign-and-verify-the-signature-with-net-and-a-certificate-c/

SP3269

Quickly coding a function that allows flattening a structure. The goal is to use in comparing complex structures, such as created by the ConvertFrom-JSON or ConvertFrom-Yaml.

Outputs a hash table.

Example:

$res = Flatten-Object @{SH = @("bin", "bash"); A = 1; B = "ZZ"; C = @{CC = "CC"}; Logic = $true}
$res.Keys | Sort-Object | % { Write-Output "$_ = $($res[$_])"}

SP3269

# Runs in PowerShell 5.1, PowerShell Core 6 on Windows and Linux, and PowerShell 7 preview

# Calculating SHA1 hash and returning it as a hexadecimal string

function Compute-SHA1Hash ([string] $string) {
    $sha1 = New-Object System.Security.Cryptography.SHA1CryptoServiceProvider
    $encoder = New-Object System.Text.UTF8Encoding
    $bytes = $encoder.GetBytes($string)
    $hash = ($sha1.ComputeHash($bytes) | % { $_.ToString("X2") }) -join ''
    return $hash

SP3269

function quicksort($in) {
    $n = $in.count
    switch ($n) {
        0 {}
        1 { $in[0] }
        2 { if ($in[0] -lt $in[1]) {$in[0], $in[1]} else {$in[1], $in[0]} }
        default {
            $anchor = $in | get-random
            $lt = $in | ? {$_ -lt $anchor}
            $eq = $in | ? {$_ -eq $anchor}

SP3269

#! /usr/bin/pwsh -nop

# This is PowerShell implementation of 2LO per https://developers.google.com/identity/protocols/OAuth2ServiceAccount
# Inputs: GCP service account with credentials, user to impersonate, and permissions to request
# Output: the access token for subsequent requests

# Using New-JWT function from the JWT module - "Install-Module JWT" if you don't have it

Import-Module JWT

SP3269

# This is a simple Powershell script that probes a system for management interface, negotiates protocol and queries management data
# Some of it is pretty standard, such as make/model/RAM/OS
# The interesting bit, quite useful in production, is the top processes by read and write I/O activity
# Run in parallel against multiple systems, and you have dataset describing your environment!

function Get-ComputerData {

    [CmdletBinding()]

    param (