[Cryptech Tech] new Novena I2C interface

[Randy Bush]

> I just committed a new version of the Novena I2C interface. I actually
> finished it last week, but have been letting it ripen (not unlike
> surströmming).
> 
> Instead of sending commands to write 4 bytes at a time, you simply
> write() 64 bytes or 128 bytes of block data, and read() the digest. All
> the init/next/ready/valid signalling is handled internally. Each hash
> core is a separate virtual I2C device, including the variations on SHA-512.
> 
> Repeated writes to the same SHA core will be added to the same digest;
> the act of reading the digest resets the internal state, so that the
> next write will start a new digest.
> 
> I also added a generic file-hashing utility to both versions of the
> Novena project, so we can make some speed comparisons. The "simple"
> version is 6.5 times faster than the "classic" version, because it skips
> the overhead of the command/response system, and starts hashing as soon
> as all block data are present. The hash.c app is also about half the
> size in the "simple" version.
> 
> In the long term, we still want to be using EIM (which I've been banging
> my head against), but this gives us another tool in the toolbox.

this is very cool.  so i have to buy a wider usb cable?  :)

randy