japh's japh II

#!/usr/bin/perl -l

$_ =

q[ for ( @_  ) {  push  @_, sort grep /\w+/, @_ }
 print  unpack  'A*', pack  'B*', join '', reverse map
 {  length ( $_  ) >>  1 }
 split  /\S+/
]

and eval
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This gets goofed when pasting from NS6, so use 'd/l code' link as appropriate.

No modules, semicolons, mirrors or smoke.

(ok, maybe a little smoke)

Spoiler tomorrow. There's a word for the type of encoding used, and I hope someone can remind me what it is :)

Comment on japh's japh II Download Code

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Re: japh's japh II
by japh (Friar) on Jan 22, 2002 at 01:47 UTC

spoiler

code used to generate this japh

$_ is assigned a string value, then eval'd. Inside the eval, $_ still contains all the code being executed, which then becomes the raw data for the code too.

Everything before 'unpack' is filler. @_ is empty so the for loop is never executed.

The print/length/split lines do this: compute how many spaces (including EOL) lie between the words in the string, subtract one (turning 1 1 2 1... into 0 0 1 0...), turn it backwards (the spacing was more aesthetically pleasing that way), pack that binary string then unpack it to ascii ('japh') and print.

The word I was looking for was 'steganography', the science of hiding data within other data. This JAPH, as it turns out, is a watered-down version of the encryption that folks suspected Bin Laden's henchmen used to communicate via pictures on eBay and porn sites. And here I thought I was being original.

There's More Than One Way To Communicate Fiendish Plans Of Destruction To Your Terrorist Operatives, apparently.

Update: cogent coined the term steganobfuscation for exactly this sort of thing :)

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