[PYTHON-CRYPTO] Doing modes in Python

[Bram Cohen]

On Sat, 28 Apr 2001, Andrew Archibald wrote:

> You don't pad.  Users can add padding in python --- in fact, a good
> policy is leave in python anything that's O(1) in the length of the
> message.  This includes ciphertext stealing, padding, arrangement of
> MAC/IV.

That's a good idea, it simplifies things a lot.

> But yes, a preliminary python implementation is worth doing and may
> well be fast enough for most people most of the time.  Get one at
> http://www.math.mcgill.ca/archibal/crypto/modes.py

I took a stab at a streaming counter mode implementation, it's at -

http://gawth.com/bram/countermode.py

I'm not done testing it yet, but I've gotta catch a plane, I'll be back
with more in a week.

-Bram Cohen

"Markets can remain irrational longer than you can remain solvent"
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