tcp/ip hardware offload

[Richard Masoner <richardm () masoner net>]

I'd like to bring up for discussion a topic I don't think I've seen before 
-- that of possible vulnerabilities in networking code in hardware 
devices.  Specifically, several vendors are developing network adapters 
with full TCP/IP offload in the hardware.  These aren't just cards with a 
network stack in firmware; a lot of these actually have the protocol 
implemented in silicon.

iReady <http://www.iready.com> is selling the "iChip," which is targeted 
for lower-end, embedded applications.  Adaptec and Intel have announced 
gigabit network adapters with full protocol offload.  Driving these 
products is the burgeoning market for network storage (iSCSI in 
particular), and the fact that OS protocol handling can gobble up over half 
of CPU cycles just to process the incoming network packets.  If you offload 
protocol handling, you free the CPU for other tasks.  From a performance 
perspective, it makes perfect sense.

I'll write to these companies for additional details (and hope for a 
response), but my guess is that the protocol is implemented in some sort of 
programmable logic on an ASIC, and that these adapters will not be 
in-circuit upgradeable.

The risk I see is the discovery of a vulnerability in these hard-wired 
"protocol accelerators."  What if a malformed packet could throw these 
adapters into an undefined state?  In a software TCP/IP stack, you just 
patch the operating system and life goes on.   What do you do with hardware 
that's discovered to be vulnerable to DoS attacks?

Is there a history of hardware being vulnerable to online DoS attacks like 
this?  Has anyone discussed this already?

Regards,

Richard Masoner