Re: Wiretapping Linux?

From: Joerg Pommnitz
Date: Wed May 17 2006 - 08:04:32 EST

--- "linux-os (Dick Johnson)" wrote:
> CPUs inside network cards (if any) don't run in the same address-space
> as your host CPU, memory, etc. Data is DMAed (set up on the host-CPU
> side) to/from this private bus, using the PCI bus. You would need
> very extensive cooperative code running on the host CPU (in the
> driver) to do anything useful. If you are going to write such
> driver code, you don't need the CPU inside the controller card
> at all because you are already running with high privileges on
> the correct bus.

Wiretapping is about listening in on communication. Network cards are the
means this communication is carried out and see all the traffic somebody
might want to tap into. This clearly makes it at least theoretically
possible to use them as a listening device (and it sees all the other
traffic on its network segment, too).

Additionally its listening on the system bus. Question: Can it tap into
data addressed to another peripheral (say the hd controller)? If so, then
only the system RAM is outside its scope.


Telefonate ohne weitere Kosten vom PC zum PC:
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at