begin quoting Andrew Lentvorski as of Fri, Aug 29, 2008 at 01:42:45AM -0700: > SJS wrote: > >begin quoting Andrew Lentvorski as of Thu, Aug 28, 2008 at 08:37:43PM > >-0700: > >>An interesting question is: why doesn't the SecurID keyfob do this? It > >>seems like a vastly more secure procedure and you wouldn't have to > >>recall all the keyfobs. You could just generate new public keys. > > > >I think it's because to make it work with a 9-digit (or so) display, > >the key is so short so as to be useless. You want a sequence of > >apparently-random numbers, using a family of prng algorithms. > > Well, I don't mind the fob having a key. I just don't want a server > compromise to compromise my fob. > > I'm thinking about how you reuse the fob. You only want one of these > things on your keychain, after all.
Ah! You're thinking of having one fob and, say, five different server that you might want to log into, but if one of the five gets cracked, you don't have to worry about the other four? Would you be adverse to having an input of some sort? You could treat it like a watch and step through the various servers. Each server would have its own secret, and you (the user) would have to select the correct display. Storing several secrets on the fob shouldn't be a problem. Slightly more difficult to use, perhaps, but you don't need to share secrets across servers. > The 8051 I was looking at (TI CC111x series) actually has an AES engine > in it. But that doesn't help for public key algorithms. Yah. But it ought to help with a hash function. -- Use accelerometers, and smack it good to switch servers. Stewart Stremler -- KPLUG-List@kernel-panic.org http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-list
