From: ph@netcom.com (Peter Hendrickson)
Date: Sat, 9 Nov 1996 09:36:29 -0800 (PST)
To: Adam Back <aba@dcs.ex.ac.uk>
Subject: Re: Why is cryptoanarchy irreversible?
Message-ID: <v02140b02aeaa6d2cfe8f@[192.0.2.1]>
MIME-Version: 1.0
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At 3:30 AM 11/9/1996, Adam Back wrote:
>Peter Hendrickson <ph@netcom.com> writes:
>> Where will you keep your secret key?  Remember, when they go through
>> your house they bring 20 young graduates from MIT who are just dying
>> to show how clever they are and save the world at the same time.

> Keep your secret key in your head.

I think this is hard to do in practice.  I have tried.

>>> This is the essence of steganography and the nature of signal and
>>> noise are fundemental principles of information theory.
>>
>> The concept of noise is not all that well defined, however.  There
>> is no way to look at a signal and say "this is all noise."
>> Sometimes physical theories may lead you to believe that it is all
>> noise.  That is fine for many applications, but when becomes less
>> convinced of things if the consequences are severe.

> Your plausible deniability has to get quite low before it will stand
> up as "proof" in court.

(This goes under 3.1 or 3.2 of my outline, which you may not have received yet.)

My idea is that the lack of noise is used as evidence to get a search
warrant.  The search warrant is used to get the evidence to put you away
forever.

(This goes under 3.3 of the outline.)

The severe penalties and significant chance of capture will keep the number
of cryptoanarchists low.

> Your real challenge is keeping your stego programs safe.  Boot
> strapping a stegoed encrypted file system while leaving no stego code
> lying around isn't that easy.

Excellent point, especially since you don't have an encrypted virtual
disk.  Can anybody resolve this?

>>>> If you are not doing it by hand, you own terrorist software and will pay
>>>> the price.

>>> Ah yes, terrorist programs like cat and perl and operating systems like
>>> Linux which contain a loopback filesystem that I can hook a perl
>>> interpreter into at compile-time (which is enough for me to rewrite the
>>> program from scratch each time if necessary, unless things like math
>>> libraries are also outlawed on computers :)  I think that the crypto
>>> concentration camps are going to be very crowded places.

>> Can you elaborate on this?  I am curious to know exactly what you are going
>> to keep in your head and what goes on the disk.  Please post the Perl
>> code that you would type in from scratch every time.

> My specialty :-)

> rc4 in C:

> #define S,t=s[i],s[i]=s[j],s[j]=t /* rc4 key <file */
> unsigned char s[256],i,j,t;main(c,v)char**v;{++v;while
> (s[++i]=i);while(j+=s[i]+(*v)[i%strlen(*v)]S,++i);for(
> j=0;c=~getchar();putchar(~c^s[t+=s[i]]))j+=s[++i]S;}

> rc4 in perl:

> #!/usr/local/bin/perl -0777-- -export-a-crypto-system-sig -RC4-3-lines-PERL
> @k=unpack('C*',pack('H*',shift));for(@t=@s=0..255){$y=($k[$_%@k]+$s[$x=$_
> ]+$y)%256;&S}$x=$y=0;for(unpack('C*',<>)){$x++;$y=($s[$x%=256]+$y)%256;
> &S;print pack(C,$_^=$s[($s[$x]+$s[$y])%256])}sub S{@s[$x,$y]=@s[$y,$x]}

(Under 3.3)  I would have a hard time memorizing these programs.  This
pretty much guarantees that the number of cryptoanarchists will be small.

(I am deeply envious of your legal right to post this code, however.
Now, why was it that we broke away from the Mother Country?)

I would like to see a longer exposition of your approach.  Given
a hostile environment, how would I operate a small anonymous perl
coding service using your techniques?  Don't forget to tell me how
I get paid and when I get to spend my "ill-gotten" gains and how
nobody will notice that I am doing it.

Peter Hendrickson
ph@netcom.com