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Date: Sun, 18 Mar 2012 13:56:33 +0800
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To: Stas Malyshev <smalyshev@sugarcrm.com>
Cc: Sam <sam.e.giles@gmail.com>, 
	"internals@lists.php.net" <internals@lists.php.net>
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Subject: Re: [PHP-DEV] Randomize hash-function in php
From: datibbaw@php.net (Tjerk Anne Meesters)

On Sun, Mar 18, 2012 at 8:12 AM, Stas Malyshev <smalyshev@sugarcrm.com> wrote:
> Obvious solution would be to use a salt for the hash, which prevents blind
> pre-computing of hash collisions. However, due to the fact that PHP hash
> values can be reused in different processes by bytecode caches, implementing
> it properly is not trivial.

What if php uses salts for specific hashes only, such as GPC (or all
hashes whose lifetime is limited to the current reuqest), and use a
zero-value salt for all others?