Re: [PATCH v2 1/4] siphash: add cryptographically secure hashtable function

[Hannes Frederic Sowa]

On 16.12.2016 00:43, Jason A. Donenfeld wrote:
> Hi Hannes,
> 
> Good news.
> 
> On Thu, Dec 15, 2016 at 10:45 PM, Hannes Frederic Sowa
> <hannes@xxxxxxxxxxxxxxxxxxx> wrote:
>>> How's that sound?
>>
>> I am still very much concerned about the API.
> 
> Thanks for pushing me and putting up with my daftness... the constant
> folding works absolutely perfectly. I've run several tests. When gcc
> knows that a struct is aligned (say, via __aligned(8)), then it erases
> the branch and makes a direct jump to the aligned code. When it's
> uncertain, it evaluates at runtime. So, now there is a single
> siphash() function that chooses the best one automatically. Behind the
> scene there's siphash_aligned and siphash_unaligned, but nobody needs
> to call these directly. (Should I rename these to have a double
> underscore prefix?) On platforms that have
> CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS, of course all of this
> disappears and everything goes directly to the aligned version.
> 
> So, I think this assuages your concerns entirely. A single API entry
> point that does the right thing.
> 
> Whew! Good thinking, and thanks again for the suggestion.

Awesome, thanks for trying this out. This basically resolves my concern
API-wise so far.

Hannes out. ;)