Re: Interesting paper by Steve Bellovin - Worm propagation in a v6 internet

[Mark Andrews <Mark_Andrews () isc org>]

> On Wed, 15 Feb 2006, Mark Andrews wrote:
>
> >     One of method missing is doing top down random walks of ip6.arpa.
>
> That's only easy if delegation were on a per-nybble basis, which is commonly
> not the case.  Because there are not typically NS's at every nybble level,
> you have to do more than one hex digit's worth of randomness in the scan in
> order to find a next-level delegation, increasing the cost of scanning that
> namespace quite a bit.
>
> (Having delegations at every nybble level would be ... alarming at best,
> given the amount of PTR redirection that implies.  :)
>
> -- 
> -- Todd Vierling <tv () duh org> <tv () pobox com> <todd () vierling name>

        A simple demonstation program.   Don't run it for too long
        as we don't really want to beat on WIDE's servers.

        Mark

#!/bin/sh
qname=1.0.0.2.ip6.arpa
depth=4
try() {
        local newqname
        local oldqname
        local l
        oldqname=$qname
        for l in 0 1 2 3 4 5 6 7 8 9 a b c d e f
        do
                newqname=$l.$oldqname
                echo trying $newqname
                dig +noques ptr $newqname > /tmp/$$xxx
                grep PTR /tmp/$$xxx
                if grep NOERROR /tmp/$$xxx > /dev/null
                then
                        qname=$newqname
                        if test $depth -lt 31
                        then
                                depth=`expr $depth + 1`
                                try
                                depth=`expr $depth - 1`
                        fi
                fi
        done
        qname=$oldqname
}

try
--
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: Mark_Andrews () isc org