From: hughes@ah.com (Eric Hughes)
Date: Mon, 30 Aug 93 14:38:50 PDT
To: cypherpunks@toad.com
Subject: The need for FREE cryptography ...
In-Reply-To: <m0oXDF6-0000nqC@vanbc.wimsey.com>
Message-ID: <9308302129.AA16834@ah.com>
MIME-Version: 1.0
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>> It would be wonderful if somebody would put a
>> reasonably secure package (much like PGP) and copyleft the source.

>Well the GNU MP library would be a good place to start [...]
>It wouldn't be much work
>to package it up with free code for Triple DES, IDEA, MD5, SHS and
>some good "random" number generation algorithms.

My own thoughts on packaging this kind of thing for general use is to
make a cryptographically enchanced PERL.

In particular, I'd add the following data types:

    - arbitrary precision integers
    - arbitrary precision modular integers (i.e. a value, modulus pair)
    - bit/byte/word vectors of specifiable lengths

I'd add the following operators

    - '*%' (ternary) modular multiplication
    - '**%' (ternary) modular exponentiation
    - '~' (binary) bit permutation
    - '~~' (binary) byte permutation

I'd add some functions

    - des()
    - armor(), disarmor()
    - gcd()
    - xgcd() which also returns the coefficients s.t. x*a + y*b = gcd(x,y)

I'd add some miscellaneous stuff like being able to read in a PGP
keyring as an associative array.  Some strong pseudorandom number
generators might be useful.  It might also be convenient to have a
fast parser for RFC822 email.

(Does everybody see where this is leading??)

And just because you _can_ easily write, say,

    $plaintext = &idea( decrypt, $ciphertext, 
	$cipherkey ** $public_exponent{ $user} % $public_modulus{ $user } )

or maybe something else, say,

    $p = & first_prime( & long_random( 510, 514 ) ) ;
    $q = & first_prime( & long_random( 510, 514 ) ) ;
    $N = $p * $q ;
    [...]

doesn't mean that the cryptographic PERL violates anybody's patent
rights in any way.

These are just my thoughts.  I'm not going to work on this, but I do
hope to inspire someone who might.

Eric