[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Faster way to deescrow Clipper




"Perry E. Metzger" says:
> 
> Mike Ingle says:
> > The attack posted here uses a brute-force search to find a phony LEAF
> > which has a valid checksum. Instead, why not just initialize the chip
> > with a session key and get the LEAF. Reset the chip and initialize it
> > with a different session key, but send the first LEAF instead of the
> > second one.
> 
> An interesting idea. 

As I've now found out (I forwarded the message to Matt -- his paper
wasn't clear on this point) this won't work. As I've said in other
messages, session keys are an element of the method used to generate
the checksum buried in the LEAF.

Perry