Cryptographer's Anthem

Lyrics © 1995 Stephen Savitzky. CC-by-nc-sa\ To the tune of ``To Anacreon in Heaven''

Lyrics [pdf]

	A	A_2	;A	B	E
	Oh, say, PGP, and R	S	A publ	ic k	ey

	A	A_2	A	E	A	B	E
Crypto	syst	ems	are	simple, with	primes $q$	and	$p$;

	A	A_2	A	B	E
Call the	product of one less	than	each of	them	$k$

	A	A_2	A	E	A
I pick	$d$	and	$e$,	whose product	is $1\bmod k$.

A A_4 A A_4 A E A E7

Now I just publ ish $d$, and the prod uct $qp$,

A A_2 A E7 A B E

You raise $d$ to the power of message block $b$;

A E A EA DE A E

Take that modul o $pq$ and send it to me .

A E A D A E A D E7 A

And I'll use it as the exponent of priv ate key $e$.

Now this program can fit into three lines of code,

Using perl and dc, though the logic's distorted.

Cryptographic machines are a weapon of war,

And the government says they must not be exported.

Make a barcoded card, or if you are a bard

run the code through a modem, it's not very hard.

\spoken{\quotation{

Now, if I were being mean I'd stick some modem tones in here}}

Then this song would be a munition, its music you could never take

From the land of the free, and the home of the brave.

The description of the RSA public key crpytography algorithm is mathematically accurate; though it's worth noting that any practical implementation will do the exponentiation and modules in a single operation. Perhaps the only obscure point occurs when specifying that $de \equiv 1 \bmod (p-1)(q-1)$. The twisted phraseology that defines $k$ as $(p-1)(q-1)$ is particularly kludgy, but what the hell, it scans.