TEA and XTEA are really, really simple and XTEA is resonably secure.
XXTEA & Block TEA have weaknesses, but XTEA should be simple enough &
fast enough for an embedded system.
Good Luck,
 -- Sztefan

http://en.wikipedia.org/wiki/XTEA
http://en.wikipedia.org/wiki/Tiny_Encryption_Algorithm

On 10/4/06, Steve Simon <steve@quintile.net> wrote:
>
> I ask here as those who read this list have an understanding of the word
> simple.
>
> I am after some very simple public key encryption code which I intend to
> use to
> encrypt the md5 of a license file on an embedded system - so in needs to
> be
> really small and simple.
>
> I am tempeted to use the plan9 RSA code, but is there somthing else even
> simpler
> about? Perhaps less secure than RSA but stronger than a password embedded
> in
> the code, XORed with 0xdeadbeef :-)
>
> Anyone seen anything on the net?
>
> -Steve
>



-- 
If work and leisure are soon to be subordinated to this one utopian
principle -- absolute busyness -- then utopia and melancholy will come to
coincide: an age without conflict will dawn, perpetually busy -- and without
consciousness.

-- Günter Grass