Re: [PATCH v2 3/4] secure_seq: use siphash24 instead of md5_transform

Jason A. Donenfeld
2016-12-14T21:01:36Z

On Wed, Dec 14, 2016 at 9:12 PM, Tom Herbert <tom@herbertland.com> wrote:
> If you pad the data structure to 64 bits then we can call the version
> of siphash that only deals in 64 bit words. Writing a zero in the
> padding will be cheaper than dealing with odd lengths in siphash24.
On Wed, Dec 14, 2016 at 9:27 PM, Hannes Frederic Sowa
<hannes@stressinduktion.org> wrote:
> What I don't really understand is that the addition of this complexity
> actually reduces the performance, as you have to take the "if (left)"
> branch during hashing and causes you to make a load_unaligned_zeropad.

Oh, duh, you guys are right. Fixed in my repo [1]. I'll submit the
next version in a day or so to let some other comments come in.

Thanks again for your reviews.

Jason

[1] https://git.zx2c4.com/linux-dev/log/?h=siphash