Directions for crypto make_checksum/verify_checksum

[Greg Hudson]

On Wed, 2009-12-09 at 15:57 -0500, Tom Yu wrote:
> Why not make an enc provider structure member that is a CBC-MAC
> function?  Some back ends have CBC-MAC functions that are likely to
> perform better than iterating over calling the block encryption
> function.

This is the direction I am taking; it works out much more cleanly than
my ECB block encryption function idea.