Re: randomdev entropy gathering is really weak

[Poul-Henning Kamp]

In message <[EMAIL PROTECTED]>, Mark Murray writes:
>> Actually, you could really use this in ntpd(8), rather than just ntpdate.
>> You could crank in the offset and delay samples for each packet
>> received from an NTP peer; this will have the effect of adding into
>> the entropy pool the "noise" in the latency of the path between you
>> and each of your NTP peers.  This varies over time with each sample,
>> and in fact, NTP goes to considerable effort in it's sample filtering
>> to exclude the noisy samples.  We need to get that date before it's
>> discarded and contribute it to the entropy cause.
>
>You forget; a snooper watching your (ether)net has access to nearly
>all of this information.

No, he doesn't have access to the offset from the machines local clock.

I ran a quick & dirty test here on some logfiles: that offset is
very close to white noise.

--
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
[EMAIL PROTECTED]         | TCP/IP since RFC 956
FreeBSD coreteam member | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.


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