Cameron Conn camconn

Program Analysis Resources

(draft; work in progress)

Changelog

All notable changes to this project will be documented in this file.

The format is based on Keep a Changelog.

[4.0] - TBD

Added

High-Performance Matrix Multiplication

This is a short post that explains how to write a high-performance matrix multiplication program on modern processors. In this tutorial I will use a single core of the Skylake-client CPU with AVX2, but the principles in this post also apply to other processors with different instruction sets (such as AVX512).

Intro

Matrix multiplication is a mathematical operation that defines the product of

Cryptopals is a set of cryptographic challenges, originally published here: https://cryptopals.com

Set 8 of the challenges was never published publicly, until late March 2018. However the cryptopals website was not updated to include the challenges. This gist compiles the 8th set of the Cryptopals challenges.

title	link
57. Diffie-Hellman Revisited: Small Subgroup Confinement	https://toadstyle.org/cryptopals/513b590b41d19eff3a0aa028023349fd.txt
58. Pollard's Method for Catching Kangaroos	https://toadstyle.org/cryptopals/3e17c7b35fcf491d08c989081ed18c9a.txt
59. Elliptic Curve Diffie-Hellman and Invalid-Curve Attacks	https://toadstyle.org/cryptopals/a0833e607878a80fdc0808f889c721b1.txt

How to use Qt that installed by Vcpkg with Qt Creator

(0) Install Qt using Vcpkg

Vcpkgを使用してQtをインストールする。(e.g. C:\vcpkg)

cd C:\vcpkg
.\vcpkg install qt5:x64-windows

Running Hashcat on Google Cloud's GPU-based VMs

In February 2017, Google announced the availability GPU-based VMs. I spun up a few of these instances, and ran some benchmarks. Along the way, I wrote down the steps taken to provision these VM instances, and install relevant drivers.

Update April 2019: Updated instructions to use instances with the Tesla T4 GPUs.

Cryptographic Best Practices

Putting cryptographic primitives together is a lot like putting a jigsaw puzzle together, where all the pieces are cut exactly the same way, but there is only one correct solution. Thankfully, there are some projects out there that are working hard to make sure developers are getting it right.

The following advice comes from years of research from leading security researchers, developers, and cryptographers. This Gist was [forked from Thomas Ptacek's Gist][1] to be more readable. Additions have been added from

	# source:http://geocities.com/SiliconValley/heights/7052/opcode.txt
	From: [email protected] (Mark Hopkins)
	Newsgroups: alt.lang.asm
	Subject: A Summary of the 80486 Opcodes and Instructions

	(1) The 80x86 is an Octal Machine
	This is a follow-up and revision of an article posted in alt.lang.asm on
	7-5-92 concerning the 80x86 instruction encoding.

	The only proper way to understand 80x86 coding is to realize that ALL 80x86

	#!/usr/bin/env python3

	"""
	Python 3 code that can decompress (to a .gvas file), or recompress (to a .savegame file)
	the UE4 savegame file that Astroneer uses.

	Though I wrote this for tinkering with Astroneer games saves, it's probably
	generic to the Unreal Engine 4 compressed saved game format.

	Examples:

	###
	###
	### UPDATE: For Win 11, I recommend using this tool in place of this script:
	### https://christitus.com/windows-tool/
	### https://github.com/ChrisTitusTech/winutil
	### https://www.youtube.com/watch?v=6UQZ5oQg8XA
	### iwr -useb https://christitus.com/win \| iex
	###
	### OR take a look at
	### https://github.com/HotCakeX/Harden-Windows-Security