This article is a continuation of the dig into the key schedule of the Serpent cipher. For clarity, we will omit the routines already given in the previous article. Let’s visualize the Serpent key schedule as a graphic: ;; 256bit(key)+1(const) x 4224(132*32) matrix, last column for constant subterms (defvar *matrix* (make-array ‘(257 4224) :element-type ‘(mod […]

This article is a continuation of the recent mega-puzzler concerning the experiment. This variant will reduce the equations. We will omit printing the input matrix, for brevity. And so: ;; Register bitness. (defconstant +bitness+ 32)   (defun flatten (l) "Flatten a tree." (cond ((null l) nil) ((atom l) (list l)) (t (mapcan #’flatten l))))   […]

This article is a byproduct of the recent mega-puzzler concerning the Serpent cipher’s key expansion procedure. Behold: ;; Register bitness. (defconstant +bitness+ 32)   (defun make-reg (reg-name bitness) "Make algebraic representation of a register (bits in descending majority)" (loop for i from (1- bitness) downto 0 collect (make-symbol (format nil "~A~A" reg-name i))))   (defun […]

This article is a continuation of “Can the Serpent Cipher fit in the ICE40 FPGA?”. Below is a revision of the forward S-box of Serpent from the previous article, with all of the S-Box equations rewritten in the same form, i.e. using strictly AND, OR, and NOT operations, with none having more than six subclauses, […]

Current Table of Contents: The question of whether the Serpent cipher could fit in a ICE40 FPGA was posed recently, and my first thought was: why not bake what appears to be the heaviest moving part, and see how many gates it requires? Then it will be possible to estimate whether the entire thing is […]

Once upon a time (in August of ’15, to be exact) I wrote a very simple versionatron called ‘V’. Edit: See also Ben Vulpes’s excellent introduction to V. V is a carefully-designed poison against the scurrying little vermin who feed on the proverbial ‘fear, uncertainty, and doubt.’ For readers who are not in the little […]

Mircea Popescu writes: ‘Now making an irc channel is quite the pleasant experience : you create something out of nothing, get to name it and are now the boss of it. For a generation devoid of proper “empire building” avenues, this is about as cool as it gets. So you can do anything you wish, […]

But, of course – it won’t. But let’s imagine that it were in someone’s financial – hell, geopolitical! interest – to convince the public that it will. The New York Times editorial might go like this: ‘you may have heard of tungsten, a metal, just like gallium; the latter, a favourite among stage magicians for melting at body temperature…’ […]

If you came here via a search engine, you were probably looking for Pierre Cartier’s wonderful mini-biography of the mathematician Alexander Grothendieck – from which I shamelessly stole the title. Please go straight there. Otherwise… “And so no one, except for two people, enters the top floor of the Aedificium. …” The abbot smiled. “No […]

Your kitchen is alive with vermin! Who is to blame? The cruel forces of nature? Or, might it be you – the fellow who scattered delicious crumbs everywhere; spilled honey a thousand times without picking up a mop once; and kept a mountain of old newspapers around for rodents to chew into nest liner? Your […]