RE: [PATCH] get_random_bytes returns the same on every boot

[Balint Marton]

On Mon, 26 Jul 2004, Eble, Dan wrote:
> If many systems are booting at the same time, is seeding with the system
> time really an appropriate solution?  Shouldn't some system-specific
> value also contribute to the randomization?

Yes, i agree, it would be nicer, if we could also use some 
system-specific stuff for the seeding, but i don't know if there is 
such data during the initialization of the random module. For example, 
we may use the MAC address of a network device, but unless i am mistaken 
the initialization of such network devices take place after the random 
dirver init. 

By the way, i made a little test with 40 computers. They were totally 
equvivalent by hardware, and all of them had a synchronized system 
clock. I turned them on by Wake On LAN exactly at the same time. All of 
them used the kernel level ip autoconfig, all of them got their right IP 
address, and i didn't even find a line of DHCPNAK in the dhcpd logfile.

Conclusion: Although using some system-specific data and the clock would 
be nicer, the system time alone also does the right thing dependably.

bye,
Cus
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