Date: Fri, 18 Aug 2000 00:51:47 -0600 From: Wes Peters <wes@softweyr.com> To: Andrey Lakhno <land@dnepr.net> Cc: sthaug@nethelp.no, security@FreeBSD.ORG Subject: Re: deny incoming icmp Message-ID: <399CDD03.EDB5F11F@softweyr.com> References: <200008171414.HAA02662@pau-amma.whistle.com> <57904.966523813@verdi.nethelp.no> <20000817191957.A5618@daemon.dnepr.net>
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Andrey Lakhno wrote:
>
> Hi sthaug!
>
> On Thu, 17 Aug 2000, sthaug@nethelp.no wrote:
>
> > > >Traceroute uses ICMP types 0 (Echo Reply), 8 (Echo request) and 11 (TTL
> > > >expired) to determine the route to the host.
> > >
> > > That didn't seem quite right to me, so I looked (in
> > > /usr/src/contrib/traceroute/traceroute.c); there is a rather large
> > > comment block near the beginning of the file tagged
> > >
> > > * -- Van Jacobson (van@ee.lbl.gov)
> > > * Tue Dec 20 03:50:13 PST 1988
> > >
> > > that explains how & why the program uses high-numbered UDP datagrams for
> > > the probes. It does rely on ICMP (time exceeded; ICMP type 11) for
> > > receiving notification from a router, though.
> >
> > The Microsoft implementation of traceroute uses ICMP instead of UDP
> > though...
>
> Where can I read about Microsoft implementation of traceroute ?
> Or could you explain in a few words how it works ?
Just grab a packet trace of it running.
--
"Where am I, and what am I doing in this handbasket?"
Wes Peters Softweyr LLC
wes@softweyr.com http://softweyr.com/
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