[Cryptography] A promising method to thwart global surveillence

[Tom Mitchell]

On Thu, May 26, 2016 at 12:29 PM, Ryan Carboni <ryacko at gmail.com> wrote:

> The Russian Illegals spy ring in New York used steganography.
>
> The Caliphate cell in Brussels used truecrypt files uploaded to
> cyberlockers in Turkey. But the grugq notes that truecrypt files would
> probably have a fixed size (and even with a random length, it would
> still round to kilobyte sizes), so it wouldn't be so simple.
>
....

> in the PDF file. The text and images of the PDF file could be
> procedurally generated.
>

If one was willing to corrupt a truecrypt file algorithmically
and perhaps strip or hack checksum checking multiple
layers of hidden messages could be in the apparently
random bits.  This applies to any encrypted or encoded
message.

PDF files are rich in possible stenography tricks.  PostScript
is even richer because it is a rich programming language as
well.

http://partners.adobe.com/public/developer/en/pdf/PDFReference.pdf

"PDF character set is divided into three classes, called regular,
delimiter, and white-space characters.
This classification determines the grouping of characters into tokens,
except within strings, streams,
and comments; different rules apply in those contexts."
Start with comments...

Font-hackery alone makes some PDF/PostScript messages odd to read and is
perhaps
a handle for steganography too.   i.e ignore all serif and kerning
characters, or key on all
serif characters. The secret key could be hidden thus:
 Yes *Bob* *is* not *your uncle, Fred is*.
Font files can be scrambled Rot13 and beyond.

A Turtle graphics program could draw a message... or a jumble depending on
a simple transformation to the source.










-- 
  T o m    M i t c h e l l
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