David's authenticated encryption mode.

Hi every one.
Just for fun I have designed an authenticated encryption mode.

* It encrypts the data.
* It authenticates the data. That is, it creates a Message
Authentication Code (MAC) for the data.
* Parts of the message can be sent in cleartext and those parts can
still be MACed.
* The encrypted message has the same size as the cleartext message. No
padding is needed.
* It only uses one single block encrypt operation per message block to
both encrypt and MAC the block. (It uses 1 additional block encrypt
operation to set-up the stream and 0-1 block operations to finalise the
stream.)
* It only uses the encrypt function of the block crypto. No need to
have the decrypt function implemented. Thus saving code space for
embedded systems.

It has not been checked by professional cryptographers so we do not
know if it is secure.

You can find the full description of the mode including diagrams etc
here:
http://www.pjort.com/daem.html

If you want to discuss with me in real time you can pretty often find
me on the IRC network irc.freenode.net in the channel #crypto with the
nick "Mole2".


Greetings from sunny Gothenburg, Sweden, Northern Europe,

.../David

--------------------------------
David Göthberg
http://www.pjort.com
Email: david(a)pjort.com
--------------------------------

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