Re: /dev/random in 2.4.6

[Steve Hill]

On Wed, 15 Aug 2001, Alex Bligh - linux-kernel wrote:

> Some network drivers generate entropy on network interrupts, some
> don't. Apparently this inconsistent state is the way people want
> to keep it.

This is very bad I would think - if the main source of entropy data is the
keybaord & mouse, there are a lot of servers out there with no keyboard
and mouse plugged into them that must be really having problems getting
enough data.

I was originally using Cobalt's kernel, so I have my suspicions that they
may have kludged the random number generator into working better with
their hardware.

> If you want to add entropy on network interrupts, look for the line
> in your driver which does a request_irq, and | in SA_SAMPLE_RANDOM
> to the flags value.

I've just added that to the natsemi ethernet driver (used on the Cobalt
Qube 3's) and the eepro100 driver (used on the Cobalt Raq 3/4) and it
seems to have fixed the problem, thanks.  I can only assume that this is
what Cobalt did to their own kernels in the first place...

> I'd prefer a single /proc/ entry to turn entropy on from ALL network
> devices for precisely the reason you state (SCSI means no IDE
> entity either), even if its off by default for ALL network
> devices for paranoia reasons, but there seems to be some religious
> issue at play which means the state currently depends on which
> brand of network card you have.

Yes, this would be a very nice idea.

-- 

- Steve Hill
System Administrator         Email: [e-mail]
Navaho Technologies Ltd.       Tel: [phone]

        ... Alcohol and calculus don't mix - Don't drink and derive! ...