Re: [Bug]? -iR <num_hosts> on windows XP generates duplicate targets

[Brandon Enright <bmenrigh () ucsd edu>]

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On Wed, 30 Apr 2008 18:06:55 -0600
David Fifield <david () bamsoftware com> wrote:

> This seems unstable to me. The IP generator would need its own random
> state to avoid being desynchronized by other things that need random
> numbers, like acknowledgement numbers. Two runs could get out of sync
> after the first scan group, if a different number of retransmits were
> necessary, say.
>
> Even if the IP generator has its own state, you could get different
> results across versions because of different reserved IP ranges.
> That's not so bad, because any IP address that became reserved would
> be omitted in the newer version and replaced by a different IP at the
> end of the list. But it means you couldn't count on the same seed
> giving you the exact same IP addresses.
>
> David Fifield

Excellent points which I overlooked.  These are fixable but mean
that implementing --seed is not simply dropping a new PRNG into nbase;
a minor re-design of how -iR works is needed.

Not all is lost though, you can always get the list of IPs you scanned
via a little awk/grep/sed of your output file and then use them later
with -iL.

I'm glad someone around here thinks these things through :-p

Brandon

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