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Message-ID: <1481921067.1054.6.camel@gmail.com>
Subject: Re: [kernel-hardening] Re: [PATCH v5 1/4] siphash: add
 cryptographically secure PRF
From: Daniel Micay <danielmicay@gmail.com>
To: kernel-hardening@lists.openwall.com,
        "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: Jean-Philippe Aumasson <jeanphilippe.aumasson@gmail.com>,
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        LKML <linux-kernel@vger.kernel.org>,
        Andy Lutomirski <luto@amacapital.net>, Netdev <netdev@vger.kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        "Theodore Ts'o" <tytso@mit.edu>, vegard.nossum@gmail.com,
        "Daniel J . Bernstein" <djb@cr.yp.to>
Date: Fri, 16 Dec 2016 15:44:27 -0500
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On Fri, 2016-12-16 at 11:47 -0800, Tom Herbert wrote:
>=20
> That's about 3x of jhash speed (7 nsecs). So that might closer
> to a more palatable replacement for jhash. Do we lose any security
> advantages with halfsiphash?

Have you tested a lower round SipHash? Probably best to stick with the
usual construction for non-DoS mitigation, but why not try SipHash 1-3,
1-2, etc. for DoS mitigation?

Rust and Swift both went with SipHash 1-3 for hash tables.
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