Re: Port Knocking questions

[Ansgar -59cobalt- Wiechers <bugtraq () planetcobalt net>]

On 2004-03-01 H Carvey wrote:
> > Does it require the hacker to be able to ping the device?
>
> Again, it depends on the implementation.  If the author of the
> application using port knocking requires an ICMP packet to be in the
> mix, then the answer would be "yes".

Not necessarily. I suppose we can assume that "being able to ping" means
that the remote host will respond with icmp-echo-replies to icmp-echo-
requests. For ICMP-based port-knocking (does this make sense at all,
since ICMP does not have ports?) the host will only need to log incoming
ICMP packets, but won't have to send echo-replies. Thus the caller won't
be able to ping the device.

Regards
Ansgar Wiechers

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