[ntp:questions] Re: ntpd transmit timestamp precision
Damion de Soto
damion at cyberguard.com.au
Wed Feb 15 04:11:15 UTC 2006
Brian Utterback wrote:
> I think that this is Damion's point. If you look at the code itself,
> the fuzz code is not used if:
> 1. You are using clock_gettime.
> 2. You are using getclock
> 3. You are using the simulator.
> So, the fact that the simulator is doing okay is irrelevant, since it
> does not use the fuzz code. But more to the point, the clock_gettime and
> getclock functions claim to return nanoseconds, so there are only two
> bits available to fuzz, so the code does not bother to fuzz those last
> two bits. Damion's point is that the actual precision of the clock
> on his system is much more coarse, so more bits are really
> non-significant and should be fuzzed, but they are not.
I have just disabled the use of clock_gettime() and am still not seeing
any bit randomization/fuzz. (Athough I'm sure I saw some yesterday....)
Where exactly is the code to fuzz the gettimeofday() value?
I can't find anything obvious.
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