Category Archives: cryptography

What is Entropy and How Do I Get More of It?

Let’s start off with one of my favorite quotes from John von Neumann: “Any one who considers arithmetical methods of producing random digits is, of course, in a state of sin. For, as has been pointed out several times, there is no such thing as a random number — there are only methods to produce random numbers, and a strict arithmetic procedure of course is not such a method.”

What von Neumann is getting at is that the “pseudo” in pseudorandom number generator (PRNG) is really a synonym for “not at all”. Granted, if you come in the middle of …read more

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Posted in cryptography, entropy, Hackaday Columns, hardware rng, hwrng, linux, linux hacks, prng, radomness, random, Raspberry Pi, rng, rng-tools, security | Leave a comment

Number Twitters

Grab a shortwave radio, go up on your roof at night, turn on the radio, and if the ionosphere is just right, you’ll be able to tune into some very, very strange radio stations. Some of these stations are just a voice — usually a woman’s voice — simply counting. Some are Morse code. All of them are completely unintelligible unless you have a secret code book. These are number stations, or radio stations nobody knows much about, but everyone agrees they’re used to pass messages from intelligence agencies to spies in the field.

A few years ago, we took …read more

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Posted in cryptography, Featured, Interest, mi6, number stations, spy, The Lincolnshire Poacher, twitter | Leave a comment

33C3: Chris Gerlinsky Cracks Pay TV

People who have incredible competence in a wide range of fields are rare, and it can appear deceptively simple when they present their work. [Chris Gerlinksy]’s talk on breaking the encryption used on satellite and cable pay TV set-top boxes was like that. (Download the slides, as PDF.) The end result of his work is that he gets to watch anything on pay TV, but getting to watch free wrestling matches is hardly the point of an epic hack like this.

The talk spans hardware reverse engineering of the set-top box itself, chip decapping, visual ROM recovery, software reverse analysis, …read more

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Posted in chip decapping, cons, crypto, cryptography, hardware, reverse engineering | Leave a comment