Re: Block cypher mode of operation for MAC

From: David Wagner (daw_at_taverner.cs.berkeley.edu)
Date: 05/20/05 

Date: Fri, 20 May 2005 16:49:25 +0000 (UTC)

giorgio.tani wrote:
>I was trying some block cyphers in CBC and PCBC (Propagating Cipher
>Block Chaining) modes in oredr to take the last block as MAC for a
>message.

My recommendation: Just use OMAC.

This stuff is subtle enough that it's not worth wasting any
brain cells (or taking the risk of making any mistakes) on
self-constructed algorithms; OMAC is safest.

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