Dmitry Sharshakov dsseng

Two Fast Methods of Generating True Random Numbers on the Arduino

Arduino true random number generator

B. Peng

December 2017

Abstract

The AVR series microcontrollers are a collection of cheap and versatile chips that are used in many applications ranging from hobbist projects to commercial infrastructure. One major problem for some hobbists is the lack of secure random number generation on the Arduino platform. The included pseudo-random number generator (PRNG) is very easy to defeat and is useless for any crypto-related uses. One recommendation from the Arduino Reference Manual is to use atmospheric noise from the chip's analog sensor pins as seed data^[6].
Unfortunately this method is extremely weak and should not be used to emulate a true random number generator (TRNG). Existing methods such as using the internal timer drift or using a dedicated generator are either too slow, requires extensive external hardware or modifications to the microcontroller's internal mech

AES67 (an open standard for high quality audio over IP) is becoming mainstream in the world of broadcast and professional audio industries, however there is a very limited amount of open source software available to interoperate with it. As a result we are often just replacing XLRs with Ethernet, without taking advantage of the possibilites the software give. While Virtual Soundcards enable some of this, native network implementations would allow greater flexibility.

This is my wishlist of things that would help change that. Hopefully one day it can be turned into a AES67 Awesome List.

As open source has resulted in very rapid evolution of the web, I believe the same is possible for professional/broadcast audio.

It is possible that some of this already exists and I just havn't found it yet. Please add a comment below if you know of something!

Convert sequence of JPEG images to MP4 video

ffmpeg -r 24 -pattern_type glob -i '*.JPG' -i DSC_%04d.JPG -s hd1080 -vcodec libx264 timelapse.mp4

-r 24 - output frame rate
-pattern_type glob -i '*.JPG' - all JPG files in the current directory
-i DSC_%04d.JPG - e.g. DSC_0397.JPG
-s hd1080 - 1920x1080 resolution

Slower, better quality

Nginx Cheat Sheet

(from Understanding Nginx Server and Location Block Selection Algorithms - https://goo.gl/YyzshP)

server {

Keybase proof

I hereby claim:

I am novemberborn on github.
I am novemberborn (https://keybase.io/novemberborn) on keybase.
I have a public key ASBotTxsIgcNBdJ7414oGO7TAGHyYaUtXfNLUrR3N-maaQo

To claim this, I am signing this object:

	# Fork vuetify https://github.com/vuetifyjs/vuetify
	git clone your-fork
	cd vuetify
	git checkout feat/docs-next
	yarn
	yarn build
	lerna run dev --scope vuetifyjs.com --stream

	const jsdom = require("jsdom");
	const { JSDOM } = jsdom;

	const dom = new JSDOM('<!DOCTYPE html><html><head></head><body></body></html>');

	global.window = dom.window;
	global.document = dom.window.document;

	// Simulate window resize event
	const resizeEvent = document.createEvent('Event');

	### 1: Drop invalid packets ###
	/sbin/iptables -t mangle -A PREROUTING -m conntrack --ctstate INVALID -j DROP

	### 2: Drop TCP packets that are new and are not SYN ###
	/sbin/iptables -t mangle -A PREROUTING -p tcp ! --syn -m conntrack --ctstate NEW -j DROP

	### 3: Drop SYN packets with suspicious MSS value ###
	/sbin/iptables -t mangle -A PREROUTING -p tcp -m conntrack --ctstate NEW -m tcpmss ! --mss 536:65535 -j DROP

	### 4: Block packets with bogus TCP flags ###

	We are going to use buildroot to download, configure and compile the kernel.

	First, download and uncompress buildroot: https://buildroot.org/download.html

	Go to the directory and:

	make qemu_x86_defconfig

	make menuconfig

	# <type>: (If applied, this commit will...) <subject> (Max 50 char)
	# \|<---- Using a Maximum Of 50 Characters ---->\|


	# Explain why this change is being made
	# \|<---- Try To Limit Each Line to a Maximum Of 72 Characters ---->\|

	# Provide links or keys to any relevant tickets, articles or other resources
	# Example: Github issue #23