DHCP!

[Bob Marcan]

Tom Mitchell wrote:
> On Wed, Feb 11, 2004 at 10:06:26AM -0200, Nelson Guedes Paulo Junior wrote:
> 
>>I'm not seeing this as a "problem", it's all working fine, the NIC's are
>>exactly the same model, but have diferent MAC's. My problem is, if a user CAN
>>change his MAC adreess, even if ONLY root can change, it's easy to implement
>>a spoofing right????
>>
>>So, why is permited to change the MAC this way??????
> 
> 
> Why?
> Because the MAC address is loaded by software.
> 
> The hardware is generic and the driver loads a MAC address commonly
> found in a very small chunk of NVRAM on the motherboard or IO card
> into the hardware.  Since the driver source is open it would be
> trivial to hack the driver and do anything.  Thus (To Me) it makes
> sense to expose it as a "feature" and not generate a false sense of
> security.
> 
> The register in most network chips permits a change on the fly.
> 
...
> --  
>   T o m   M i t c h e l l 
>   mitch48-at-sbcglobal-dot-net
> 
> 

Just for info from the legacy guy:
Digital Decnet phase IV packs area.node address into the MAC.
So there is no need for the ARP.

Regards, Bob

-- 
  Bob Marcan                     mailto:bob.marcan at hermes-plus.si
  Aster^H^H...HermesPlus^H^H^H...S&T
  Slandrova ul. 2                       tel:    +386 (1) 5895-200
  1000 Ljubljana, Slovenia              http://www.hermes-plus.si