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Learning Rust

Getting Started + Installation | Cheat Sheet

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Usage

Use the capacities-sidebars.css as a snippet and paste the markdown into a new note.

MD5 Collision with CRC32 Preimage

Here's the scenario: We want to craft two different messages with the same MD5 hash, and a specific CRC32 checksum, simultaneously.

In other words, we want an MD5 collision attack and a CRC32 preimage attack.

This might seem like a contrived scenario, but it's exactly the one I faced while producing my PNG hashquine (Yes OK maybe that's also a contrived scenario, cut me some slack).

On its own, a CRC32 preimage attack is trivial. You can craft a 4-byte suffix that gives any message a specific checksum, calculated using a closed-form expression (which I am too lazy to derive, not even with assistance from Z3). It's not an attack per-se, since CRC32 was never meant to be cryptograpically secure in the first place.

	#import "@preview/cetz:0.2.0"
	#let d = cetz.draw

	#let offset(anchor, x: 0, y: 0) = {
	(v => cetz.vector.add(v, (x, y)), anchor)
	}
	#let default-colors = (red, orange, yellow, green, blue, purple, fuchsia, gray)
	#let color-boxed(..args) = {
	set text(0.8em)
	box(

	# Depends on FZF

	# Remove the default cd alias
	Remove-Alias cd
	# Create a new cd function
	function MyCD {
	Set-Location @args
	$curtime =$(Get-Date -Format "yyyy-MM-dd HH:mm:ss")
	$dict = @{
	Id = "30"

	# This Action autogenerates PDFs and standalone HTML
	# out of your Overleaf projects (or any LaTeX-live project).
	#
	# PDF generator: pdflatex
	# HTML generator: htlatex
	#
	# Both tools come from LaTeX Live and are executed on
	# the latest version of Ubuntu.
	#
	# Given:

	// insert everything in the browser console and a "file" button will appear in the submenu

	function addfilebutton() {
	if (document.querySelector("#file2xy") \|\| // exists already
	!document.querySelector(".dcg-action-newimage")) // unclick case
	return
	pic = document.querySelector(".dcg-action-newimage").parentNode
	var div = document.createElement('div');
	div.innerHTML = '<style>.dcg-calculator-api-container .dcg-icon-new-file::before { content: "\\e205";}</style><div class="dcg-new-item dcg-action-newfile" onclick="file2tab.click()"><i class="dcg-icon-new-file dcg-expression-icon" aria-hidden="true"></i>Datei2tab</div><input id="file2tab" type="file" style="display: none" onchange="tabFromFile()"></div>'
	pic.after(div)

	%%
	% Copyright (c) 2017 - 2021, Pascal Wagler;
	% Copyright (c) 2014 - 2021, John MacFarlane
	%
	% All rights reserved.
	%
	% Redistribution and use in source and binary forms, with or without
	% modification, are permitted provided that the following conditions
	% are met:
	%