SIPHASH (was: Re: [GIT] Networking)

From: Geert Uytterhoeven
Date: Thu Feb 23 2017 - 05:29:38 EST


Hi Jason,

On Wed, Feb 22, 2017 at 5:31 AM, David Miller <davem@xxxxxxxxxxxxx> wrote:
> 3) Introduce SIPHASH and it's usage for secure sequence numbers and
> syncookies. From Jason A. Donenfeld.

> Jason A. Donenfeld (4):
> siphash: add cryptographically secure PRF
> siphash: implement HalfSipHash1-3 for hash tables
> secure_seq: use SipHash in place of MD5
> syncookies: use SipHash in place of SHA1

bloat-o-meter v4.10.. says:

add/remove: 338/127 grow/shrink: 604/310 up/down: 86156/-24117 (62039)
...
siphash_4u64 - 5006 +5006
siphash_3u64 - 4298 +4298
siphash_2u64 - 3582 +3582
__siphash_unaligned - 3052 +3052
__siphash_aligned - 3052 +3052
siphash_3u32 - 2976 +2976
siphash_1u64 - 2870 +2870
siphash_1u32 - 2172 +2172
...

Do we need all of this builtin, unconditionally?

Thanks for your answer!

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds