Re: Sources of entropy - /dev/random problem for network servers

[Jeff Garzik <jgarzik@mandrakesoft.com>]

Alex Bligh - linux-kernel wrote:
> The machine in question is locked in a data center (can't be
> the only one) and thus sees none of the former two. IDE Entropy
> comes from executed IDE commands. The disk is physically largely
> inactive due to caching. But there's plenty of network traffic
> which should generate IRQs.

Use a hardware random number generator if you need a lot of entropy. 
The i810 RNG driver and userspace tools at
http://sourceforge.net/project/gkernel/ provide an example for an
implementation, if your hardware is not i8xx.


> However, only 3 drivers in drivers/net actually set
> SA_SAMPLE_RANDOM when calling request_irq(). I believe
> all of them should.

No, because an attacker can potentially control input and make it
non-random.

	Jeff


-- 
Jeff Garzik       | Sam: "Mind if I drive?"
Building 1024     | Max: "Not if you don't mind me clawing at the dash
MandrakeSoft      |       and shrieking like a cheerleader."