From: Pavel Machek <pavel@ucw.cz>
Subject: Re: [PATCH] random: add random_initialized command line param
Date: Tue, 23 Jun 2015 22:44:11 +0200
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Cc: Ted Tso <tytso@mit.edu>, linux-crypto@vger.kernel.org,
	linux-kernel@vger.kernel.org
To: Stephan Mueller <smueller@chronox.de>
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On Mon 2015-05-18 18:25:25, Stephan Mueller wrote:
> Make the threshold at which the output entropy pools are considered to
> be initialized configurable via a kernel command line option. The
> current integer value of 128 bits is a good default value. However, some
> user groups may want to use different values. For example, the SOGIS
> group now requires 125 bits at least (BSI, the participant at that group
> used to require 100 bits). NIST moved from 80 bits to 112 bits starting
> with 2014.
> 
> It is therefore to be expected that in the future, this threshold may
> increase for different user groups.

Speaking of random and kernel parameters... should we add random=<hex
digits> parameter to pass entropy from bootloader to the kernel?

u-boot-SPL does DRAM calibration, for example, and I guess that may
provide some rather hard to guess values...

[I initialy misread parameter below as "random_initize=" and thought
it does exactly this...]
								Pavel

> +	random_initialized= [KNL] Set the threshold in bits at which the
> +			Linux random number generator considers an output
> +			entropy pool initialized.
> +			Format: <int> (must be >= 112 and <= size of output
> +				       entropy pool in bits)
> +			Default: 128
> +
-- 
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